398 results on '"M. Mercado"'
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2. Escritura creativa en ambientes socioculturales para el fortalecimiento de la producción textual, en los estudiantes de grado cuarto
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Jheymi C. Heredia Vergara and Deiris M. Mercado Ramos
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General Medicine - Abstract
El siguiente trabajo se deriva de la investigación que establece como objetivo, analizar las trasformaciones generadas en la producción textual en los estudiantes de grado cuarto de la institución educativa el Chiquí y la enseñanza de la escritura docente, luego de la implementación de una estrategia pedagógica de escritura creativa con enfoque sociocultural. Los objetivos específicos fueron: Identificar las características de la producción textual en los estudiantes; caracterizar las prácticas de enseñanza de la escritura de la docente; determinar los rasgos de diseño de una estrategia pedagógica ( secuencia didáctica) y evaluar los resultados de la implementación de dicha estrategia, esto a través de diferentes técnicas de recolección de información como: observaciones, entrevistas y talleres diagnósticos; por lo tanto, el proyecto se enmarca en el paradigma sociocritico, con un enfoque de tipo cualitativo, bajo los preceptos del método de investigación acción; lo cual permitió analizar la realidad del ámbito académico, identificando los procesos de enseñanza aprendizaje desde la competencia escritural; concluyendo a su vez, que la producción textual transmitida a través de la escritura creativa dentro del contexto escolar, es necesaria, puesto que permite abrir espacios de imaginación e inventiva que conlleven al estudiante a romper paradigmas de enseñanzas tradicionales, ya que el acto de escribir es una habilidad que no mide límites y que actúa como parte esencial del engranaje sociocultural que necesita el ser humano para poder comunicarse.
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- 2023
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3. Prospective Evaluation of a Standardized Approach to Improve Procedure Speed in Esophageal Endoscopic Submucosal Dissection
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Firas Bahdi, Michael M. Mercado, Xiaofan Huang, Kristen A. Staggers, Noor Zabad, and Mohamed O. Othman
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Gastroenterology ,Radiology, Nuclear Medicine and imaging - Published
- 2023
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4. The ozone–climate penalty over South America and Africa by 2100
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Flossie Brown, Gerd A. Folberth, Stephen Sitch, Susanne Bauer, Marijin Bauters, Pascal Boeckx, Alexander W. Cheesman, Makoto Deushi, Inês Dos Santos, Corinne Galy-Lacaux, James Haywood, James Keeble, Lina M. Mercado, Fiona M. O'Connor, Naga Oshima, Kostas Tsigaridis, Hans Verbeeck, Laboratoire d'aérologie (LAERO), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)
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Atmospheric Science ,TROPOSPHERIC OZONE ,AIR-QUALITY ,MODEL ,SULFUR-DIOXIDE ,DRY DEPOSITION ,Meteorology and Climatology ,CHEMISTRY ,[SDU]Sciences of the Universe [physics] ,Earth and Environmental Sciences ,cavelab ,SURFACE OZONE ,ISOPRENE EMISSIONS ,VEGETATION ,FUTURE CLIMATE - Abstract
Climate change has the potential to increase surface ozone (O3) concentrations, known as the “ozone–climate penalty”, through changes to atmospheric chemistry, transport and dry deposition. In the tropics, the response of surface O3 to changing climate is relatively understudied but has important consequences for air pollution and human and ecosystem health. In this study, we evaluate the change in surface O3 due to climate change over South America and Africa using three state-of-the-art Earth system models that follow the Shared Socioeconomic Pathway 3-7.0 emission scenario from CMIP6. In order to quantify changes due to climate change alone, we evaluate the difference between simulations including climate change and simulations with a fixed present-day climate. We find that by 2100, models predict an ozone–climate penalty in areas where O3 is already predicted to be high due to the impacts of precursor emissions, namely urban and biomass burning areas, although on average, models predict a decrease in surface O3 due to climate change. We identify a small but robust positive trend in annual mean surface O3 over polluted areas. Additionally, during biomass burning seasons, seasonal mean O3 concentrations increase by 15 ppb (model range 12 to 18 ppb) in areas with substantial biomass burning such as the arc of deforestation in the Amazon. The ozone–climate penalty in polluted areas is shown to be driven by an increased rate of O3 chemical production, which is strongly influenced by NOx concentrations and is therefore specific to the emission pathway chosen. Multiple linear regression finds the change in NOx concentration to be a strong predictor of the change in O3 production, whereas increased isoprene emission rate is positively correlated with increased O3 destruction, suggesting NOx-limited conditions over the majority of tropical Africa and South America. However, models disagree on the role of climate change in remote, low-NOx regions, partly because of significant differences in NOx concentrations produced by each model. We also find that the magnitude and location of the ozone–climate penalty in the Congo Basin has greater inter-model variation than that in the Amazon, so further model development and validation are needed to constrain the response in central Africa. We conclude that if the climate were to change according to the emission scenario used here, models predict that forested areas in biomass burning locations and urban populations will be at increasing risk of high O3 exposure, irrespective of any direct impacts on O3 via the prescribed emission scenario.
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- 2022
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5. Improved representation of plant physiology in the JULES-vn5.6 land surface model: photosynthesis, stomatal conductance and thermal acclimation
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Rebecca J. Oliver, Lina M. Mercado, Doug B. Clark, Chris Huntingford, Christopher M. Taylor, Pier Luigi Vidale, Patrick C. McGuire, Markus Todt, Sonja Folwell, Valiyaveetil Shamsudheen Semeena, and Belinda E. Medlyn
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General Medicine ,JULES ,Atmospheric Sciences - Abstract
Carbon and water cycle dynamics of vegetation are controlled primarily by photosynthesis and stomatal conductance (gs). Our goal is to improve the representation of these key physiological processes within the JULES land surface model, with a particular focus on refining the temperature sensitivity of photosynthesis, impacting modelled carbon, energy and water fluxes. We test (1) an implementation of the Farquhar et al. (1980) photosynthesis scheme and associated plant functional type-dependent photosynthetic temperature response functions, (2) the optimality-based gs scheme from Medlyn et al. (2011) and (3) the Kattge and Knorr (2007) photosynthetic capacity thermal acclimation scheme. New parameters for each model configuration are adopted from recent large observational datasets that synthesise global experimental data. These developments to JULES incorporate current physiological understanding of vegetation behaviour into the model and enable users to derive direct links between model parameters and ongoing measurement campaigns that refine such parameter values. Replacement of the original Collatz et al. (1991) C3 photosynthesis model with the Farquhar scheme results in large changes in GPP for the current day, with ∼ 10 % reduction in seasonal (June–August, JJA, and December–February, DJF) mean GPP in tropical forests and ∼ 20 % increase in the northern high-latitude forests in JJA. The optimality-based gs model decreases the latent heat flux for the present day (∼ 10 %, with an associated increase in sensible heat flux) across regions dominated by needleleaf evergreen forest in the Northern Hemisphere summer. Thermal acclimation of photosynthesis coupled with the Medlyn gs scheme reduced tropical forest GPP by up to 5 % and increased GPP in the high-northern-latitude forests by between 2 % and 5 %. Evaluation of simulated carbon and water fluxes by each model configuration against global data products shows this latter configuration generates improvements in these key areas. Thermal acclimation of photosynthesis coupled with the Medlyn gs scheme improved modelled carbon fluxes in tropical and high-northern-latitude forests in JJA and improved the simulation of evapotranspiration across much of the Northern Hemisphere in JJA. Having established good model performance for the contemporary period, we force this new version of JULES offline with a future climate scenario corresponding to rising atmospheric greenhouse gases (Shared Socioeconomic Pathway (SSP5), Representative Concentration Pathway 8.5 (RCP8.5)). In particular, these calculations allow for understanding of the effects of long-term warming. We find that the impact of thermal acclimation coupled with the optimality-based gs model on simulated fluxes increases latent heat flux (+50 %) by the year 2050 compared to the JULES model configuration without acclimation. This new JULES configuration also projects increased GPP across tropical (+10 %) and northern-latitude regions (+30 %) by 2050. We conclude that thermal acclimation of photosynthesis with the Farquhar photosynthesis scheme and the new optimality-based gs scheme together improve the simulation of carbon and water fluxes for the current day and have a large impact on modelled future carbon cycle dynamics in a warming world.
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- 2022
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6. Use of buccal fat pad-derived stem cells cultured on bioceramics for repair of critical-sized mandibular defects in healthy and osteoporotic rats
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Fabio Camacho-Alonso, M. R. Tudela-Mulero, J. A. Navarro, A. J. Buendía, and A. M. Mercado-Díaz
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General Dentistry - Abstract
Objective To compare new bone formation in mandibular symphysis critical-sized bone defects (CSBDs) in healthy and osteoporotic rats filled with bioceramics (BCs) with or without buccal fat pad mesenchymal stem cells (BFPSCs). Materials and methods Thirty-two adult female Sprague–Dawley rats were randomized to two groups (n = 16 per group): group 1 healthy and group 2 osteoporotic (with bilateral ovariectomy). The central portion of the rat mandibular symphysis was used as a physiological CSBD. In each group, eight defects were filled with BC (hydroxyapatite 60% and β-tricalcium phosphate 40%) alone and eight with BFPSCs cultured on BC. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). Results In both groups, CSBDs filled with BC + BFPSCs showed greater radiological bone union, BMD and histological bone union, and more VEGF and BMP-2 positivity, compared with CSBDs treated with BC alone at 4 and 8 weeks. Conclusions The application of BFPSCs cultured on BCs improves bone regeneration in CSBDs compared with BCs alone in healthy and osteoporotic rats. Clinical relevance Our results may aid bone regeneration of maxillofacial CSBDs of both healthy and osteoporotic patients, but further studies are necessary.
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- 2022
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7. Acclimation of photosynthetic capacity and foliar respiration in Andean tree species to temperature change
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Andrew J. F. Cox, Iain P. Hartley, Patrick Meir, Stephen Sitch, Mirindi Eric Dusenge, Zorayda Restrepo, Sebastian González‐Caro, Juan Camilo Villegas, Johan Uddling, and Lina M. Mercado
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Meteorology and Climatology ,photosynthesis ,tropical montane forests ,Physiology ,Botany ,elevation gradient ,Plant Science ,acclimation ,Ecology and Environment ,respiration - Abstract
Climate warming is causing compositional changes in Andean tropical montane forests (TMFs). These shifts are hypothesised to result from differential responses to warming of cold- and warm-affiliated species, with the former experiencing mortality and the latter migrating upslope. The thermal acclimation potential of Andean TMFs remains unknown.Along a 2000 m Andean altitudinal gradient, we planted individuals of cold- and warm-affiliated species (under common soil and irrigation), exposing them to the hot and cold extremes of their thermal niches, respectively. We measured the response of net photosynthesis (Anet), photosynthetic capacity and leaf dark respiration (Rdark) to warming/cooling, 5 months after planting.In all species, Anet and photosynthetic capacity at 25°C were highest when growing at growth temperatures (Tg) closest to their thermal means, declining with warming and cooling in cold-affiliated and warm-affiliated species, respectively. When expressed at Tg, photosynthetic capacity and Rdark remained unchanged in cold-affiliated species, but the latter decreased in warm-affiliated counterparts. Rdark at 25°C increased with temperature in all species, but remained unchanged when expressed at Tg.Both species groups acclimated to temperature, but only warm-affiliated species decreased Rdark to photosynthetic capacity ratio at Tg as temperature increased. This could confer them a competitive advantage under future warming.
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- 2023
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8. Impact of ultra-short pauses between stacked lesions with and without active esophageal cooling
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M Mercado Montoya, T Gomez Bustamante, E Kulstad, E Berjano, S Mickelsen, P Hernandez Arango, A Gonzalez Suarez, J Schieber, and J Daniels
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Abstract
Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Research reported in this abstract was supported by the National Heart, Lung, And Blood Institute of the National Institutes of Health under Award Number R44HL158375 (the content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health). Background Placing lesions at the same point (stacking lesions) in the left atrium during radiofrequency (RF) ablation can increase the risk of collateral injury. The use of active esophageal cooling has been shown to significantly reduce the risk of thermal injury to the esophagus, but stacking of lesions may overcome these protective effects. Longer pauses between lesions may reduce this risk, but the effect of very short pauses has not been previously quantified. Purpose To examine the impact of ultra-short pauses between stacked lesions with and without active esophageal cooling. Methods Using a computational model of the left atrium, we measured the effect of RF ablation in the left atrium on injury formation in the esophagus. Models with and without active esophageal cooling, using a dedicated esophageal cooling device, were created. Using a power of 50 W for 10 s, with up to 3 sequential lesions placed in the same location, we used the Arrhenius equation to quantify the fraction of damage (FOD) in the esophageal wall. The time between lesions was set to as short as 1 s, and results were compared to prior studies using longer pauses of up to 20 s. To account for thermal latency, measures of esophageal damage were taken both immediately after RF ablation, and again 90 s afterwards. Results With active cooling in place, esophageal injury was eliminated with active esophageal cooling after the first lesion placement, but reached 21% transmurality without cooling. Lesion transmurality increased after each lesion due to thermal latency, but active esophageal cooling prevented this effect when only one lesion was placed. Subsequent lesions resulted in esophageal injury when placed in the same location. After 3 lesions with 1 s pauses between each, esophageal injury transmurality reached 91% without cooling in place, and 22% with active cooling in place (Figure 1). In contrast, analysis of the intended lesions in the atrial wall demonstrated minimal effects from cooling (Figure 2). Conclusions Active esophageal cooling significantly reduces esophageal injury from RF ablation, but placing additional lesions at the same point can overcome the heat extraction capacity of a dedicated cooling device. Decreased time between lesions exacerbates this risk, with an ultra-short pause of one second posing the greatest risk.
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- 2023
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9. The contemporary Amazon Forest carbon budget
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Lina M Mercado, Celso Von Randow, Thais Michele Rosan, and Luana Basso
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The Amazon is the largest continuous tropical forest in the world and plays a key role in the global carbon cycle. Human-induced disturbances (e.g., deforestation and wildfires) in combination with climate change have impacted its carbon cycling. However, uncertainties remain on the magnitude of carbon fluxes associated with human-induced disturbances and the old-growth forest sink, and thus the net land carbon balance of the Amazon. Here we synthesize state-of-the-art estimates of the land carbon flux components in the Amazon. To quantify the human-disturbance fluxes from deforestation, land use and land cover changes and degradation, we use a set of bookkeeping models. The annual intact sink was quantified using a set of 16 Dynamic Global Vegetation Models (DGVMs). We then combine the carbon flux estimates from disturbances with the intact sink estimates to provide a bottom-up estimate of the net land carbon flux and compare them alongside top-down estimates from atmospheric model inversions. Between 2010 and 2018, the net land carbon flux in the Brazilian Amazon estimated with the bottom-up approach was -59 (±160) Tg C yr-1 and +36 (±125) Tg C yr-1 with the top-down approach. Despite disagreeing on the sign of the flux, this analysis suggests that the Brazilian Amazon was on average near carbon neutral over the 2010-2018 period, given the large uncertainties underlying both methods. The net land carbon fluxes for the years 2019 and 2020 based on the bottom-up approach were larger than for 2010-2018. This is likely primarily due to direct emissions related to an increase in deforestation although it may possibly be partly caused by a weakening of the forest carbon sink, both in response to deforestation and a warming climate. Spatially, both methodologies agree that the south-eastern Amazon was a net carbon source over the whole study period. These results have important implications for the mitigation potential of Brazilian ecosystems within the goals of the Paris Agreement.
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- 2023
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10. Implementation of trait-based ozone plant sensitivity in the Yale Interactive terrestrial Biosphere model v1.0 to assess global vegetation damage
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Yimian Ma, Xu Yue, Stephen Sitch, Nadine Unger, Johan Uddling, Lina M. Mercado, Cheng Gong, Zhaozhong Feng, Huiyi Yang, Hao Zhou, Chenguang Tian, Yang Cao, Yadong Lei, Alexander W. Cheesman, Yansen Xu, and Maria Carolina Duran Rojas
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General Medicine - Abstract
A major limitation in modeling global ozone (O3) vegetation damage has long been the reliance on empirical O3 sensitivity parameters derived from a limited number of species and applied at the level of plant functional types (PFTs), which ignore the large interspecific variations within the same PFT. Here, we present a major advance in large-scale assessments of O3 plant injury by linking the trait leaf mass per area (LMA) and plant O3 sensitivity in a broad and global perspective. Application of the new approach and a global LMA map in a dynamic global vegetation model reasonably represents the observed interspecific responses to O3 with a unified sensitivity parameter for all plant species. Simulations suggest a contemporary global mean reduction of 4.8 % in gross primary productivity by O3, with a range of 1.1 %–12.6 % for varied PFTs. Hotspots with damage >10 % are found in agricultural areas in the eastern US, western Europe, eastern China, and India, accompanied by moderate to high levels of surface O3. Furthermore, we simulate the distribution of plant sensitivity to O3, which is highly linked with the inherent leaf trait trade-off strategies of plants, revealing high risks for fast-growing species with low LMA, such as crops, grasses, and deciduous trees.
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- 2023
11. Early Secondary Alveolar Bone Grafting and Facial Growth of Patients with Complete Unilateral Cleft Lip and Palate
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Jean-Charles Doucet, Kathleen A. Russell, John Daskalogiannakis, Ana M. Mercado, Ronald R. Hathaway, Gunvor Semb, William C. Shaw, and Ross E. Long
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Otorhinolaryngology ,Oral Surgery - Abstract
Objective To investigate the craniofacial growth outcomes of early secondary alveolar bone grafting(ABG) around 6 years of age. Design Retrospective cohort study Setting 1 North-American and 5 Northern-European cleft centers. Subjects 33 subjects with CUCLP consecutively treated with secondary ABG around 6 years of age were compared to 105 subjects from 4 centers treated with late secondary ABG and 19 subjects from 1 center with primary ABG. Methods Preorthodontic standardized lateral cephalometric radiographs taken after 12 years of age were traced and analyzed according to the Eurocleft Study protocol. Fourteen angular and two proportional measurements were performed. Measurement means from the Study Center(SC) were compared to 5 Northern-European centers using analysis of variance and Welch's modified t-tests, and P Results For the SC, the mean age ± SD at the time of bone graft was 5.85 ± 0.71 years and the mean age at the time of the lateral cephalogram was 13.4 ± 1.8 years. The sagittal maxillary prominence of the SC was favorably comparable to the 5 Northern-European centers. The mean SNA (78.1 ± 4.3) for the SC was significantly higher compared to 4 of the 5 Northern-European centers(all P Conclusions Craniofacial growth outcomes of early secondary ABG around 6 years compare favorably to the outcomes of late secondary ABG.
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- 2022
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12. The Growing Field of Nonprofit Accounting Research: 21st Century Data Sources, Topics, and Opportunities
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Julie M Mercado, Linda M. Parsons, and Kyle A. Smith
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We document trends in nonprofit accounting research during the past two decades, specifically identifying data sources used, research topics investigated, and journals that published this work. Accessibility to new data sources has allowed scholars to broaden the overall scope of research questions examined and better understand the ramifications of a wide variety of factors on organizational performance, managers' behavior, and donor decision making. Our findings indicate that accessible and affordable digitized data opened the field to scholars who may have previously perceived data collection as a barrier to entry in the field. Nonprofit accounting research has increased significantly and is now published broadly in a wide array of journals. As the field has developed, those who conduct nonprofit research have diversified the data sources and research methods in their research designs. Overall, the trends in availability and variety of data bode well for the future of nonprofit accounting research.
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- 2022
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13. Hepatopulmonales Syndrom
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M Mercado Rivera, M Malfertheiner, and A Mohr
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- 2023
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14. Nitrogen and Phosphorus co-limitation impact on temperate forests productivity
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Andre (Mahdi) Nakhavali, Lina M. Mercado, Iain P. Hartley, and Stephen Sitch
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Global process-based models with dynamic vegetation and functions show an increasing ongoing land carbon (C) sink, primarily due to CO2 fertilization effects (Sitch et al., 2008; Schimel et al., 2015). However, the phosphorus (P) and Nitrogen (N) related processes may constrain the plant’s photosynthetic and growth capacity and the C sink magnitude in temperate forests consequently (Aerts and Chapin, 1999; Vitousek et al., 1997; Vitousek, 2004). The co-limitation of N and P changes the plant C fixation capacity and the uptake of the atmospheric CO2 consequently. However, modelling studies are incapable of reproducing the productivity decrease due to these limitations (Fleischer et al., 2019). In this study, we introduced the P dynamics, and its interaction with N and C cycles in the Joint UK Land Environment Simulator (JULES-CNP), and parametrized and calibrated it using a well-site Free-Air Carbon Enrichment (FACE) facility in Mill Haft woodland, England. We further investigate the role of N and P availability and limiting impact on C cycles under different CO2 conditions. Furthermore, we modified the SOC representation in JULES (RothC model) to simulate observed Soil C soil stabilization capacity that is mainly related to soil texture. Our study shows an NPP reduction due to N and P limitation under both ambient and elevated CO2 conditions at the study site. Furthermore, using an improved SOC model in JULES, our results show an increase in soil C turnover with rising CO2 which leads to lower equilibrium soil C stocks than expected from the rise in soil C input alone. Reference: Aerts, R. and Chapin, F. S.: The Mineral Nutrition of Wild Plants Revisited: A Re-evaluation of Processes and Patterns, Adv. Ecol. Res., 30, 1–67, https://doi.org/10.1016/S0065-2504(08)60016-1, 1999. Fleischer, K., Rammig, A., De Kauwe, M. G., Walker, A. P., Domingues, T. F., Fuchslueger, L., Garcia, S., Goll, D. S., Grandis, A., Jiang, M., Haverd, V., Hofhansl, F., Holm, J. A., Kruijt, B., Leung, F., Medlyn, B. E., Mercado, L. M., Norby, R. J., Pak, B., von Randow, C., Quesada, C. A., Schaap, K. J., Valverde-Barrantes, O. J., Wang, Y.-P., Yang, X., Zaehle, S., Zhu, Q., and Lapola, D. M.: Amazon forest response to CO2 fertilization dependent on plant phosphorus acquisition, Nat. Geosci., 12, 736–741, https://doi.org/10.1038/s41561-019-0404-9, 2019. Vitousek, P. M.: Nutrient Cycling and Limitation: Hawai’i as a Model System, Princeton University Press, 2004. Vitousek, P. M., Mooney, H. A., Lubchenco, J. M., and Melillo, J. M.: Human Domination of Earth Ecosystems, Science (80-. )., 278, 21, 1997.
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- 2023
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15. Factors influencing the prediction accuracy of model peptides in reversed-phase liquid chromatography
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Othman Al Musaimi, Oscar M. Mercado-Valenzo, and Daryl R. Williams
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Filtration and Separation ,Analytical Chemistry - Abstract
Hydrophobicity is an important physicochemical property of peptides in solution. As well as being strongly associated with peptide stability and aggregation, hydrophobicity governs the solution based chromatographic separation processes, specifically reversed-phase liquid chromatography (RPLC). In addition, hydrophobicity is a major physicochemical property of peptides in comparison to H-bonding, electrostatic, and aromatic properties in intermolecular interactions. However, a wide range of molecular factors can influence peptide hydrophobicity, with accurate predictions depending on specific peptide amino acid compositions, structure, and conformation. It is noticeable that peptide composition, the position of the amino acid, and its neighbouring groups play a crucial role in the elution process. In light of this, the same amino acid behaved differently depending on its position and neighbouring amino acid in the peptide chain. Extra attention should be paid to the denaturation process during the course of elution, as it has been shown to complicate and alter the elution pattern. This paper reports on the key peptide properties that can alter hydrophobicity and, consequently, the RPLC elution behaviour of the peptides, and it will conclude by proposing improved prediction algorithms for peptide elution in RPLC.
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- 2023
16. The ChatGPT Artificial Intelligence Chatbot: How Well Does It Answer Accounting Assessment Questions?
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David A. Wood, Muskan P. Achhpilia, Mollie T. Adams, Sanaz Aghazadeh, Kazeem Akinyele, Mfon Akpan, Kristian D. Allee, Abigail M. Allen, Elizabeth D. Almer, Daniel Ames, Viktor Arity, Dereck Barr-Pulliam, K. Asli Basoglu, Andrew Belnap, Jeremiah W. Bentley, Terje Berg, Nathan R. Berglund, Erica Berry, Avishek Bhandari, Md Nazmul Hasan Bhuyan, Paul W. Black, Eva Blondeel, David Bond, Annika Bonrath, A. Faye Borthick, Erik S. Boyle, Marianne Bradford, Duane M. Brandon, Joseph F. Brazel, Bryan G. Brockbank, Marcus Burger, Dmitri Byzalov, James N. Cannon, Cecil Caro, Abraham H. Carr, Jack Cathey, Ryan Cating, Kimberly Charron, Stacy Chavez, Jason Chen, Jennifer C. Chen, Jennifer W. Chen, Christine Cheng, Xu Cheng, Brant E. Christensen, Kimberly Swanson Church, N. J. Cicone, Patience Constance, Lauren A. Cooper, Candice L. Correia, Joshua Coyne, W. Alec Cram, Asher Curtis, Ronald J. Daigle, Steve Dannemiller, Stephan A. Davenport, Gregory S. Dawson, Karen J. L. De Meyst, Scott Dell, Sebahattin Demirkan, Christine A. Denison, Hrishikesh Desai, Steven DeSimone, Leah M. Diehl, Ruth Dimes, Bei Dong, Amy Donnelly, Adam du Pon, Huijue Kelly Duan, Ada Duffey, Ryan T. Dunn, Mary P. Durkin, Ann C. Dzuranin, Rachel M. Eberle, Matthew S. Ege, Dina El Mahdy, Adam Esplin, Marc Eulerich, Patricia Everaert, Nusrat Farah, Lauren Farish, Michael Favere-Marchesi, Dutch Fayard, Jessica R. Filosa, Melinda Ford, Diana R. Franz, Bachman P. Fulmer, Sarah Fulmer, Zhan Z. Furner, Sonia Gantman, Steve Garner, Jace Garrett, Xin Geng, Joanna Golden, William Goldman, Josue Gomez, Mark Gooley, Shawn P. Granitto, Karen Y. Green, Cindy L. Greenman, Gaurav Gupta, Ronald N. Guymon, Kevin Hale, Christopher J. Harper, S. Allen Hartt, Holly Hawk, Steven R. Hawkins, Erin M. Hawkins, David C. Hay, Rafael Heinzelmann, Cassy D. Henderson, Bradley E. Hendricks, William G. Heninger, Mary S. Hill, Nicole Holden, D. Kip Holderness, Travis P. Holt, Jeffrey L. Hoopes, Sheng-Feng Hsieh, Feiqi Huang, Hua-Wei Huang, Ting-Chiao Huang, Brian W. Huels, Kara Hunter, Patrick J. Hurley, Kerry Inger, Sharif Islam, Isaac Ison, Hussein Issa, Andrew B. Jackson, Scott C. Jackson, Diane J. Janvrin, Peggy D. Jimenez, Daniel Johanson, J. Scott Judd, Brett S. Kawada, Andrea Seaton Kelton, Sara Kern, Jon N. Kerr, Marsha B. Keune, Mindy Kim, Brian D. Knox, Gregory Kogan, Amr Kotb, Ronja Krane, Joleen Kremin, Kimberly S. Krieg, Jonathan Kugel, Ellen M. Kulset, Chamara Kuruppu, Garrison LaDuca, Barbara A. Lamberton, Melvin A. Lamboy-Ruiz, Bradley Lang, Stephannie A. Larocque, Melissa P. Larson, Bradley P. Lawson, James G. Lawson, Lorraine Lee, Margarita M. Lenk, Michelle Li-Kuehne, Jonathan Liljegren, Yi-Hung Lin, Wu-Po Liu, Zishang Liu, Brandon Lock, James H. Long, Tina Loraas, Suzanne Lowensohn, Thomas R. Loy, Hakim Lyngstadaas, Wim Maas, Jason E. MacGregor, Dag Øivind Madsen, Carissa L. Malone, Maximilian Margolin, Mary E. Marshall, Rachel M. Martin, Colleen McClain Mpofu, Chris McCoy, Nicholas C. McGuigan, Dwayne N. McSwain, Michele D. Meckfessel, Mark J. Mellon, Olivia S. Melton, Julie M. Mercado, Steven Mitsuda, Kennedy Modugu, Stephen Moehrle, Amirali Moeini Chaghervand, Kevin Moffitt, Joon Seok Moon, Brigitte Muehlmann, Johnna Murray, Emmanuel S. Mwaungulu, Noah Myers, J. Conrad Naegle, Martin J. Ndicu, Aaron S. Nelson, Anh L. Nguyen, Thomas Niederkofler, Ehsan Nikbakht, Ann D. O'Brien, Kehinde M. Ogunade, Daniel O'Leary, Mitchell J. Oler, Derek K. Oler, Kari Joseph Olsen, John I. Otalor, Kyle W. Outlaw, Michael. E. Ozlanski, Jenny Parlier, Jeffrey S. Paterson, Christopher A. Pearson, Michael J. Petersen, Steven T. Petra, Matthew D. Pickard, Jeffrey Pickerd, Robert Pinsker, Catherine Plante, James M. Plečnik, Richard A. Price, Linda A. Quick, Jana Raedy, Robyn Raschke, Julie Ravenscraft, Vernon Richardson, Brett A. Rixom, John F. Robertson, Iyad Rock, Miles A. Romney, Andrea Rozario, Michael F. Ruff, Kathleen Rupley, Ali Saeedi, Aaron Saiewitz, Leigh W. Salzsieder, Sayan Sarkar, Michael Saulls, Tialei A. Scanlan, Tammie J. Schaefer, Daniel Schaupp, Gary P. Schneider, Andreas Seebeck, R. Drew Sellers, Samantha C. Seto, Romi-Lee Sevel, Yuxin Shan, Matthew G. Sherwood, Maggie Singorahardjo, Hanna Kristin Skaftadottir, Justyna Skomra, Jason L. Smith, Dallin O. Smith, James Smith, Mason C. Snow, Ryan D. Sommerfeldt, Kate B. Sorensen, Trevor L. Sorensen, Andrew C. Spieler, Matthew A. Stallings, Lesya Stallings, Alan Stancill, Jonathan D. Stanley, Chad M. Stefaniak, Nathaniel M. Stephens, Bryan W. Stewart, Theophanis C. Stratopoulos, Daniel A. Street, Meena Subedi, Scott L. Summers, Charlotte H. Sundkvist, Christina Synn, Amanuel Tadesse, Gregory P. Tapis, Kerri Tassin, Samantha Taylor, Mary Teal, Ryan Teeter, Meredith Tharapos, Jochen C. Theis, Jack Thomas, Kristen S. Thompson, Todd A. Thornock, Wendy Tietz, Anthony M. Travalent, Brad S. Trinkle, J. Mike Truelson, Michael C. Turner, Brandon Vagner, Hamid Vakilzadeh, Jesse van der Geest, Victor van Pelt, Scott D. Vandervelde, Jose Vega, Sandra Vera-Muñoz, Brigham Villanueva, Nishani Edirisinghe Vincent, Martin Wagener, Stephanie Walton, Rick C. Warne, Olena V. Watanabe, David Watson, Marcia Weidenmier Watson, Jill Weber, Thomas Weirich, Ashley N. West, Amanda L. Wilford, Aaron B. Wilson, Brian Winrow, Timothy Winrow, Tasia S. Winrow, Denise Wiseman, Annie L. Witte, Bryan D. Wood, Jessica Wood, Darryl Woolley, Nicole S. Wright, Juan Wu, Xiaomei Xiong, Dimitri Yatsenko, Courtney E. Yazzie, Glen M. Young, Chanyuan Zhang, Aleksandra B. Zimmerman, Emily Zoet, Department of Accounting & Control, and Accounting Group
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Accounting ,Education - Abstract
ChatGPT, a language-learning model chatbot, has garnered considerable attention for its ability to respond to users’ questions. Using data from 14 countries and 186 institutions, we compare ChatGPT and student performance for 28,085 questions from accounting assessments and textbook test banks. As of January 2023, ChatGPT provides correct answers for 56.5 percent of questions and partially correct answers for an additional 9.4 percent of questions. When considering point values for questions, students significantly outperform ChatGPT with a 76.7 percent average on assessments compared to 47.5 percent for ChatGPT if no partial credit is awarded and 56.5 percent if partial credit is awarded. Still, ChatGPT performs better than the student average for 15.8 percent of assessments when we include partial credit. We provide evidence of how ChatGPT performs on different question types, accounting topics, class levels, open/closed assessments, and test bank questions. We also discuss implications for accounting education and research.
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- 2023
17. South American mountain ecosystems and global change – a case study for integrating theory and field observations for land surface modelling and ecosystem management
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Laszlo Nagy, Cleiton B. Eller, Lina M. Mercado, Francisco X. Cuesta, Luís D. Llambí, Erika Buscardo, Luiz E. O. C. Aragão, Carlos García-Núñez, Rafael S. Oliveira, Milton Barbosa, Sergio J. Ceballos, Marco Calderón-Loor, G. Wilson Fernandes, Ezequiel Aráoz, Ariadna M. Q. Muñoz, Ricardo Rozzi, Francisco Aguirre, Esteban Álvarez-Dávila, Norma Salinas, and Stephen Sitch
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Ecology ,Plant Science ,Ecology, Evolution, Behavior and Systematics - Abstract
Plot-based monitoring has yielded much information on the taxonomic diversity and carbon (C) storage in tropical lowland forests of the Amazon basin. This has resulted in an improved understanding of the relationship between lowland forest biomass dynamics and global change drivers, such as climate change and atmospheric CO2 concentration. Much less attention has been paid to the mountain ecosystems of South America that comprise montane forests and alpine vegetation (páramo, puna, high Andean grasslands, wetlands, and alpine heath). This vegetation complex provides a variety of ecosystem services and forms a natural laboratory along various physiographic, geological and evolutionary history/biogeography, and land use history gradients. Here, we review existing empirical understanding and model-based approaches to quantify the contribution of mountain ecosystems to ecosystem service provision in the rapidly changing socioecological setting of the South American mountains. The objective of this paper is to outline a broad road map for the implementation of mountain vegetation into dynamic global vegetation models (DGVM) for use in Earth System Models (ESM), based on our current understanding of their structure and function and of their responsiveness to global change drivers. We also identify treeline processes, critical in mountain ecosystems, as key missing elements in DGVMs/ESMs, and thus explore in addition a treeline model. Stocktaking of the availability of empirical data was undertaken from eight research sites along the Andes and in south-eastern Brazil. Out of eight sites, two (one each in Venezuela and Brazil) had some climate, ecological and ecophysiological data potentially suitable to parametrise a DGVM. Tree biomass data were available for six sites. A preliminary assessment of the Joint UK Land Environment Simulator (JULES) DGVM was made to identify gaps in available data and their impacts on model parametrisation and calibration. Additionally, the potential climate-determined elevation of the treeline was modelled to check the DGVM for its ability to identify the transition between the montane forest and alpine vegetation. Outcomes of the evaluation of the JULES land surface model identified the following key processes in montane forests: temperature-related decrease in net primary production, respiration, and allocation to above-ground biomass and increase in soil C stocks with elevation. There was a variable agreement between simulated biomass and those derived from field measurements via allometric equations. We identified major gaps between data availability and the needs for process-based modelling of South American mountain vegetation and its dynamics in DGVMs. To bridge this gap, we propose a transdisciplinary network, composed of members of the theoretical/modelling and empirical scientific communities, to study the natural dynamics of mountain ecosystems and their responses to global change drivers locally, regionally and at the continental scale, within a social-ecological system framework. The work presented here forms the basis for the design of data collection from field measurements and instrumental monitoring stations to parametrise and verify DGVMs. The network is designed to collaborate with and complement existing long-term research initiatives in the region and will adopt existing standard field protocols. Complementary protocols will ensure compatibility between field data collection and data needed for process-based and empirical models.
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- 2023
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18. A Comprehensive Evaluation of Enterobacteriaceae Primer Sets for Analysis of Host-Associated Microbiota
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Carolina N. Resendiz-Nava, Hilda V. Silva-Rojas, Angel Rebollar-Alviter, Dulce M. Rivera-Pastrana, Edmundo M. Mercado-Silva, and Gerardo M. Nava
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Microbiology (medical) ,Infectious Diseases ,General Immunology and Microbiology ,Proteobacteria ,primer set ,Immunology and Allergy ,Medicine ,taxonomic update ,Enterobacterales ,Molecular Biology ,Enterobacteriaceae ,16S rRNA - Abstract
Enterobacteriaceae is one of the most important bacterial groups within the Proteobacteria phylum. This bacterial group includes pathogens, commensal and beneficial populations. Numerous 16S rRNA gene PCR-based assays have been designed to analyze Enterobacteriaceae diversity and relative abundance, and, to the best of our knowledge, 16 primer pairs have been validated, published and used since 2003. Nonetheless, a comprehensive performance analysis of these primer sets has not yet been carried out. This information is of particular importance due to the recent taxonomic restructuration of Enterobacteriaceae into seven bacterial families. To overcome this lack of information, the identified collection of primer pairs (n = 16) was subjected to primer performance analysis using multiple bioinformatics tools. Herein it was revealed that, based on specificity and coverage of the 16S rRNA gene, these 16 primer sets could be divided into different categories: Enterobacterales-, multi-family-, multi-genus- and Enterobacteriaceae-specific primers. These results highlight the impact of taxonomy changes on performance of molecular assays and data interpretation. Moreover, they underline the urgent need to revise and update the molecular tools used for molecular microbial analyses.
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- 2022
19. Dança circular e biodança: promoção de saúde e qualidade de vida
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Lucas M. Mercado Lobo, Gabriel Diaz Godinho, Gisele Arent Suzin, Vanessa da Silva Corralo, Débora T. de Resende Silva, and Josiano Guilherme Puhle
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Cada vez mais se buscam alternativas visando à melhora da saúde e da qualidade de vida da população, tendo em vista as diversas transformações e situações onde o mundo atual se encontra. Nesse sentido, a Agenda 2030 para o Desenvolvimento Sustentável, proposta durante a Assembleia Geral das Nações Unidas no ano de 2015, trata a saúde e bem-estar como um dos objetivos a serem desenvolvidos ao nível mundial. No Brasil, através do Sistema Único de Saúde, a promoção de saúde está diretamente ligada ao desenvolvimento de ações pautadas na melhora da qualidade de vida dos indivíduos, das quais se destaca a Política Nacional de Práticas Integrativas e Complementares, instituída no ano de 2006. Dentro dessa política é possível identificar práticas corporais responsáveis por promover e afetar de maneira positiva inúmeros aspectos que compõem a saúde do ser humano, onde se destacam as sessões de Danças Circulares e de Biodança, que buscam por meio do movimento e da dança estabelecer vivências significativas para cada indivíduo.
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- 2022
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20. An analysis of the influence of atrial wall thickness on the protective effects of proactive esophageal cooling during high-power short-duration radiofrequency ablation
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M Mercado Montoya, T Gomez Bustamante, E Berjano, P Hernandez Arango, S Mickelsen, J Schieber, E Kulstad, and J Daniels
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Cardiology and Cardiovascular Medicine - Abstract
Background The use of proactive esophageal cooling using a dedicated cooling device during radiofrequency (RF) left atrial ablation has increased, with endoscopic studies showing reductions in esophageal lesions using medium power ablation settings. With no atrioesophageal fistula yet identified using esophageal cooling, and clinical practice increasingly shifting to high-power short-duration (HPSD) ablation, additional data on the protective potential of this technique in HPSD ablation may help guide RF ablation strategies. In particular, a better understanding of the effects of anatomical variations in myocardial thickness on cooling efficacy is warranted. Purpose We sought to evaluate the influence of atrial wall thickness on the protective effects of proactive esophageal cooling during HPSD ablation. Methods Using a computer model of the left atrium and esophagus, we analyzed the esophageal damage that occurs under two HPSD ablation conditions (50 W for 10 s and 90 W for 4 s) with and without proactive esophageal cooling while varying atrial wall thickness. Injury to the esophagus was quantified using the Arrhenius equation as well as by determining the percentage of tissue reaching a 50°C lethal isotherm. Atrial thickness was varied between 0.6 mm to 2.0 mm. Esophageal cooling was set to the recommended 4°C coolant temperature. Results Using 50 W power settings in control (non-cooled) conditions, esophageal lesion transmurality ranged from 75% to 82% as calculated by the Arrhenius equation, with decreased transmurality seen as atrial wall thickness increased. With the addition of proactive cooling, lesion transmurality decreased to less than 43% in the thinnest atrial wall sections, and to less than 25% in the thickest atrial wall sections. Using 90 W power settings, control conditions showed esophageal lesion transmurality ranging from 52% to 63%, with the greatest damage seen in the middle-range atrial thicknesses (1 and 1.5 mm). Active esophageal cooling reduced this esophageal injury to less than 12% transmurality through the esophagus in all anatomic scenarios. Conclusions Modeling suggests that the use of proactive esophageal cooling significantly reduces esophageal lesion transmurality under HPSD ablation conditions across a range of typical atrial wall thicknesses, including in very thin myocardium, where the risk of esophageal injury is greatest. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Attune
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- 2022
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21. Assessment of short-term spatio-temporal variability in the structure of mesozooplankton communities integrating microscopy and multigene high-throughput sequencing
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Lidia Yebra, Candela García-Gómez, Nerea Valcárcel-Pérez, Alma Hernández de Rojas, Leocadio Blanco-Bercial, M. Carmen Castro, Francisco Gómez-Jakobsen, and Jesús M. Mercado
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COI ,Centro Oceanográfico de Málaga ,Metabarcoding ,trophic relationships ,Aquatic Science ,Medio Marino ,Oceanography ,Zooplankton - Abstract
Variability in composition and structure of the mesozooplankton communities in the Bay of Malaga (SW Mediterranean) were characterized during a 26 h cycle using an integrative taxonomic approach. We combined microscopic identification of organisms, with metabarcoding for the genes of the mitochondrial DNA COI and the V9 hypervariable region of the ribosomal RNA 18S. Richness and diversity obtained by microscopy were higher than those measured with COI, as COI did not detect some phyla. COI however allowed for the identification to species level of several taxa that were left at higher taxonomic rank under the microscope. 18S detected a wider range of taxa than COI and microscopy, although with lower taxonomic resolution. Differences between coastal-night and shelf-day zooplankton communities structure were detected by both microscopy and metabarcoding. The combination of these two approaches increased the known copepod species in the SW Mediterranean Sea by 9%. An integrative approach combining morphology and COI metabarcoding is proposed to further facilitate mesozooplankton biodiversity studies., SI
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- 2022
22. Impact of Polymer Residue Level on the In-Plane Thermal Conductivity of Suspended Large-Area Graphene Sheets
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Julian Anaya, Elisha J M Mercado, and Martin Kuball
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Materials science ,Fabrication ,02 engineering and technology ,Chemical vapor deposition ,010402 general chemistry ,01 natural sciences ,law.invention ,symbols.namesake ,Thermal conductivity ,law ,Thermal ,Thermoelectric effect ,CDTR ,General Materials Science ,Raman ,chemistry.chemical_classification ,Graphene ,Thermoelectric ,Nanopatterning ,Polymer ,021001 nanoscience & nanotechnology ,PMMA ,0104 chemical sciences ,chemistry ,Chemical engineering ,symbols ,Thermal management ,0210 nano-technology ,Raman spectroscopy - Abstract
The presence of polymer transfer residues on graphene surfaces is a major bottleneck to overcome for the commercial and industrial viability of devices incorporating graphene layers. In particular, how clean the surface must be to recover high (>2500 W/mK) thermal conductivity and maximize the heat spreading capability of graphene for thermal management applications remains unclear. Here, we present the first systematic study of the impact of different levels of polymer residues on the in-plane thermal conductivity (κr) of single-layer graphene (SLG) fabricated by chemical vapor deposition (CVD). Control over the quantity of surface residue was achieved by varying the length of time each sample was rinsed in toluene to remove the poly(methyl methacrylate) (PMMA) support layer. The level of residue contamination was assessed using atomic force microscopy (AFM) and optical characterization. The thermal conductivity of the suspended SLG was measured using an optothermal Raman technique. We observed that the presence of polymer surface residue has a significant impact on the thermal properties of SLG, with the most heavily contaminated sample exhibiting a κr as low as (905 +155/–100) W/mK. Even without complete eradication of surface residues, a thermal conductivity as high as (3100 +1400/–900) W/mK was recovered, where the separation between adjacent clusters was sufficiently large (>700 nm). The proportion of the SLG surface covered by residues and the mean separation distance between clusters were found to be key factors in determining the level of κr suppression. This work has important implications for future large-scale graphene fabrication and transfer, particularly where graphene is to be used as a heat spreading layer in devices. The possibility of new opportunities for manipulation of the thermal properties of SLG via PMMA nanopatterning is also raised.
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- 2021
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23. Perceptions of intercultural religious music and intercultural competence in a Southern U.S. public middle school eighth grade women’s choir: A case study
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Emily M. Mercado
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Intercultural competence ,Judaism ,05 social sciences ,050401 social sciences methods ,050301 education ,Sacred music ,Music education ,Focus group ,Education ,0504 sociology ,Cultural diversity ,Pedagogy ,Choir ,Psychology ,0503 education ,Cultural competence ,Music - Abstract
The purpose of this case study was to examine the researcher’s perceptions of student participants’ intercultural competence during rehearsals, focus groups, and interviews and the perceived benefits and challenges when implementing a researcher-designed curricular unit titled Religious Choral Music from the Christian, Jewish, and Muslim Worlds in one eighth grade middle school women’s choir. Using Deardorff’s intercultural competence process framework, which provides a method for exploring and categorizing elements of intercultural competence including attitudes, knowledge/skills, internal outcomes, and external outcomes, the researcher adapted Deardorff’s framework to represent how the student participants demonstrated intercultural competence during the music unit, focus groups, and interviews. The perceived benefits of the music unit included student participants’ emerging intercultural competence — their positive attitudes and knowledge of unfamiliar religions broadened their cultural understanding, and their internal and external behaviors demonstrated respect toward religious and cultural differences. The perceived challenges of the music unit included a lack of resources, assumptions that emerged as a result of teaching about religious music, and intersections that occurred for some between religious music at their school, home, and house of worship. Finally, implications for teaching practice based on these findings are that music teachers should consider engaging students in discussions surrounding the religious and cultural elements of diverse religious music intended to foster intercultural competence.
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- 2021
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24. Synucleinopathy-associated pathogenesis in Parkinson’s disease and the potential for brain-derived neurotrophic factor
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Caryl E. Sortwell, Kathryn M. Miller, and Natosha M. Mercado
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0301 basic medicine ,Cell biology ,Parkinson's disease ,Context (language use) ,Review Article ,Disease ,Neuroprotection ,Pathogenesis ,03 medical and health sciences ,Cellular and Molecular Neuroscience ,0302 clinical medicine ,Neurotrophic factors ,Basal ganglia ,medicine ,RC346-429 ,Brain-derived neurotrophic factor ,business.industry ,medicine.disease ,030104 developmental biology ,Neurology ,nervous system ,Neurology (clinical) ,Neurology. Diseases of the nervous system ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The lack of disease-modifying treatments for Parkinson’s disease (PD) is in part due to an incomplete understanding of the disease’s etiology. Alpha-synuclein (α-syn) has become a point of focus in PD due to its connection to both familial and idiopathic cases—specifically its localization to Lewy bodies (LBs), a pathological hallmark of PD. Within this review, we will present a comprehensive overview of the data linking synuclein-associated Lewy pathology with intracellular dysfunction. We first present the alterations in neuronal proteins and transcriptome associated with LBs in postmortem human PD tissue. We next compare these findings to those associated with LB-like inclusions initiated by in vitro exposure to α-syn preformed fibrils (PFFs) and highlight the profound and relatively unique reduction of brain-derived neurotrophic factor (BDNF) in this model. Finally, we discuss the multitude of ways in which BDNF offers the potential to exert disease-modifying effects on the basal ganglia. What remains unknown is the potential for BDNF to mitigate inclusion-associated dysfunction within the context of synucleinopathy. Collectively, this review reiterates the merit of using the PFF model as a tool to understand the physiological changes associated with LBs, while highlighting the neuroprotective potential of harnessing endogenous BDNF.
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- 2021
25. Historical and future global burned area with changing climate and human demography
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Chao Wu, Sergey Venevsky, Lina M. Mercado, Chris Huntingford, Stephen Sitch, and A. Carla Staver
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Earth system science ,Urbanization ,Fire protection ,Earth and Planetary Sciences (miscellaneous) ,Tropics ,Climate change ,Environmental science ,Physical geography ,Subtropics ,Dynamic global vegetation model ,Ecology and Environment ,General Environmental Science ,Carbon cycle - Abstract
Summary Wildfires influence terrestrial carbon cycling and represent a safety risk, and yet a process-based understanding of their frequency and spatial distributions remains elusive. We combine satellite-based observations with an enhanced dynamic global vegetation model to make regionally resolved global assessments of burned area (BA) responses to changing climate, derived from 34 Earth system models and human demographics for 1860–2100. Limited by climate and socioeconomics, recent BA has decreased, especially in central South America and mesic African savannas. However, future simulations predict increasing BA due to changing climate, rapid population density growth, and urbanization. BA increases are especially notable at high latitudes, due to accelerated warming, and over the tropics and subtropics, due to drying and human ignitions. Conversely, rapid urbanization also limits BA via enhanced fire suppression in the immediate vicinity of settlements, offsetting the potential for dramatic future increases, depending on warming extent. Our analysis provides further insight into regional and global BA trends, highlighting the importance of including human demographic change in models for wildfire under changing climate.
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- 2021
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26. Assessment of oceanographic services for the monitoring of highly anthropised coastal lagoons: The Mar Menor case study
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Alberto Granero, José G. Giménez, Andrés Bueno-Crespo, Javier Senent-Aparicio, Francisco Gómez-Jakobsen, Jesús M. Mercado, Pablo Blanco-Gómez, Constancio Amurrio-García, Juan M. Ruiz, José Cecilia, and Granero, A.
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History ,monitoring ,Polymers and Plastics ,Centro Oceanográfico de Málaga ,Phytoplankton ,lagoons ,coastal lagoons ,Satellite images ,Business and International Management ,Medio Marino ,Eutrophication ,Nutrient pollution ,Industrial and Manufacturing Engineering - Abstract
Ocean monitoring systems are designed for continuous monitoring to track their evolution and anticipate environmental issues. However, they are often based on IoT systems that offer little spatial coverage and are hard to maintain. Satellite remote sensing offers good geographical coverage but they also face several challenges to become a monitoring system. This paper introduces an easy-to-use software tool to crawl water-quality data from up to 6 satellite instruments from the ESA and NASA. Particularly, Chl-a data is deeply analyzed in terms of reliability and data coverage for a highly anthropised coastal lagoon (Mar Menor, Spain), where serious socio-environmental issues are happening. Our results show a good linear correlation between in situ data and SRS data, reaching values close to 0.9, and stating the relevance of organic matter inputs from ephemeral streams in Chl-a concentrations. Moreover, temporal granularity is increased from 5 to 1.5 days by combining SRS sources.
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- 2022
27. Differential nutrient limitation and tree height control leaf physiology, supporting niche partitioning in tropical dipterocarp forests
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David C. Bartholomew, Lindsay F. Banin, Paulo R. L. Bittencourt, Mohd Aminur Faiz Suis, Lina M. Mercado, Reuben Nilus, David F. R. P. Burslem, and Lucy Rowland
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leaf traits ,Ekologi ,Ecology ,Botany ,Botanik ,trait plasticity ,Ecology and Environment ,ontogeny ,Borneo ,leaf respiration ,generalist ,rainforest ,Ecology, Evolution, Behavior and Systematics ,photosynthetic capacity - Abstract
1. Revealing the mechanisms of environmental niche partitioning within lowland tropical forests is important for understanding the drivers of current species distributions and potential vulnerability to environmental change. Tropical forest structure and species composition change across edaphic gradients in Borneo over short distances. However, our understanding of how edaphic conditions affect tree physiology and whether these relationships drive niche partitioning within Bornean forests remains incomplete. 2. This study evaluated how leaf physiological function changes with nutrient availability across a fine-scale edaphic gradient and whether these relationships vary according to tree height. Furthermore, we tested whether intraspecific leaf trait variation allows generalist species to populate a wider range of environments. 3. We measured leaf traits of 218 trees ranging in height from 4 to 66 m from 13 dipterocarp species within four tropical forest types (alluvial, mudstone, sandstone and kerangas) occurring along an
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- 2022
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28. Representation of the phosphorus cycle in the Joint UK Land Environment Simulator (vn5.5_JULES-CNP)
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Mahdi André Nakhavali, Lina M. Mercado, Iain P. Hartley, Stephen Sitch, Fernanda V. Cunha, Raffaello di Ponzio, Laynara F. Lugli, Carlos A. Quesada, Kelly M. Andersen, Sarah E. Chadburn, Andy J. Wiltshire, Douglas B. Clark, Gyovanni Ribeiro, Lara Siebert, Anna C. M. Moraes, Jéssica Schmeisk Rosa, Rafael Assis, José L. Camargo, and Asian School of the Environment
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Meteorology and Climatology ,Soil Fertility ,Phosphorus Cycle ,General Medicine ,Environmental engineering [Engineering] - Abstract
Most land surface models (LSMs), i.e. the land components of Earth system models (ESMs), include representation of nitrogen (N) limitation on ecosystem productivity. However, only a few of these models have incorporated phosphorus (P) cycling. In tropical ecosystems, this is likely to be important as N tends to be abundant, whereas the availability of rock-derived elements, such as P, can be very low. Thus, without a representation of P cycling, tropical forest response in areas such as Amazonia to rising atmospheric CO2 conditions remain highly uncertain. In this study, we introduced P dynamics and its interactions with the N and carbon (C) cycles into the Joint UK Land Environment Simulator (JULES). The new model (JULES-CNP) includes the representation of P stocks in vegetation and soil pools, as well as key processes controlling fluxes between these pools. We develop and evaluate JULES-CNP using in situ data collected at a low-fertility site in the central Amazon, with a soil P content representative of 60 % of soils across the Amazon basin, to parameterize, calibrate, and evaluate JULES-CNP. Novel soil and plant P pool observations are used for parameterization and calibration, and the model is evaluated against C fluxes and stocks and those soil P pools not used for parameterization or calibration. We then evaluate the model at additional P-limited test sites across the Amazon and in Panama and Hawaii, showing a significant improvement over the C- and CN-only versions of the model. The model is then applied under elevated CO2 (600 ppm) at our study site in the central Amazon to quantify the impact of P limitation on CO2 fertilization. We compare our results against the current state-of-the-art CNP models using the same methodology that was used in the AmazonFACE model intercomparison study. The model is able to reproduce the observed plant and soil P pools and fluxes used for evaluation under ambient CO2. We estimate P to limit net primary productivity (NPP) by 24 % under current CO2 and by 46 % under elevated CO2. Under elevated CO2, biomass in simulations accounting for CNP increase by 10 % relative to contemporary CO2 conditions, although it is 5 % lower compared to CN- and C-only simulations. Our results highlight the potential for high P limitation and therefore lower CO2 fertilization capacity in the Amazon rainforest with low-fertility soils.
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- 2022
29. Understanding water and energy fluxes in the Amazonia: Lessons from an observation‐model intercomparison
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Paul Moorcroft, Xubin Zeng, A. C. Araujo, Scott R. Saleska, Marcos Longo, Yadvinder Malhi, Marcos Heil Costa, Natalia Restrepo-Coupe, Hewlley Maria Acioli Imbuzeiro, Ian Baker, Loren P. Albert, David R. Fitzjarrald, Naomi M. Levine, Bradley O. Christoffersen, Lina M. Mercado, David W. Galbraith, and Celso von Randow
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0106 biological sciences ,Biogeochemical cycle ,010504 meteorology & atmospheric sciences ,Forests ,Sensible heat ,Atmospheric sciences ,010603 evolutionary biology ,01 natural sciences ,Ecology and Environment ,Evapotranspiration ,Latent heat ,medicine ,Environmental Chemistry ,Ecosystem ,0105 earth and related environmental sciences ,General Environmental Science ,Global and Planetary Change ,Ecology ,Water ,Seasonality ,Albedo ,medicine.disease ,05 Environmental Sciences, 06 Biological Sciences ,Environmental science ,Canopy interception ,Seasons ,Interception ,Brazil - Abstract
Tropical forests are an important part of global water and energy cycles, but the mechanisms that drive seasonality of their land‐atmosphere exchanges have proven challenging to capture in models. Here, we (1) report the seasonality of fluxes of latent heat (LE), sensible heat (H), and outgoing short and longwave radiation at four diverse tropical forest sites across Amazonia ‐‐ along the equator from the Caxiuanã and Tapajós National Forests in the eastern Amazon to a forest near Manaus, and from the equatorial zone to the southern forest in Reserva Jaru; (2) investigate how vegetation and climate influence these fluxes; and (3) evaluate land surface model (LSM) performance by comparing simulations to observations. We found that previously identified failure of models to capture observed dry‐season increases in evapotranspiration was associated with model over‐estimations of (1) magnitude and seasonality of Bowen ratios (relative to aseasonal observations in which sensible was only 20‐30% of the latent heat flux) indicating model exaggerated water limitation, (2) canopy emissivity and reflectance (albedo was only 10 to 15% of incoming solar radiation, compared to 0.15‐0.22% simulated), and (3) vegetation temperatures (due to underestimation of dry‐season evapotranspiration and associated cooling). These partially compensating model‐observation discrepancies (e.g. higher temperatures expected from excess Bowen ratios were partially ameliorated by brighter leaves and more interception/evaporation) significantly biased seasonal model estimates of net radiation (Rn), the key driver of water and energy fluxes (LE ~ 0.6Rn and H ~ 0.15Rn). Though these biases varied among sites and models. A better representation of energy‐related parameters associated with dynamic phenology (e.g. leaf optical properties, canopy interception, and skin temperature) could improve simulations and benchmarking of current vegetation‐atmosphere exchange and reduce uncertainty of regional and global biogeochemical models.
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- 2021
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30. Coping with the new norm: ICT-pedagogy integration awareness and competencies of TEI faculty
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Michael E. Mananghaya, Regidor G. Gaboy, Michael C. Mabalay, Mark Gill M. Mercado, and Belinda M. Romblon
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Coping (psychology) ,Information and Communications Technology ,Norm (group) ,ComputingMilieux_COMPUTERSANDEDUCATION ,Mathematics education ,Theory and practice of education ,Psychology ,LB5-3640 - Abstract
This study examined the Information and Communications Technology (ICT) -pedagogy integration awareness and competencies of faculty membersof a teacher education institution (TEI). Descriptive research methodwas employed through the use of survey questionnaire to collect data.Fifty (50) faculty membersserved as respondentsin this study.Most of the respondents perceived themselves to be extremely aware of utilizing ICT tools/ equipment and moderately aware of using application software despite reporting that they were self-taught in acquiring basic ICT skills. They were also found to be proficient in terms of level of competency in integration. It was also discovered that mostareas of their competency were significantly related to respondents’ awareness in using ICT. This paper suggests that higher education institutions should devise innovative teacher training programs that will increase the ICT pedagogy awareness and integration of teacher education faculty members.
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- 2020
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31. Isotopically Enhanced Thermal Conductivity in Few-Layer Hexagonal Boron Nitride: Implications for Thermal Management
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Martin Kuball, Elisha J M Mercado, Chao Yuan, Yan Zhou, James H. Edgar, and Jiahan Li
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interfacial thermal ,Materials science ,Hexagonal boron nitride ,Thermal management of electronic devices and systems ,isotope engineering ,symbols.namesake ,Thermal conductivity ,symbols ,Interfacial thermal resistance ,CDTR ,thermal conductivity ,General Materials Science ,hexagonal boron nitride ,two-dimensional materials ,Composite material ,Raman spectroscopy ,Raman ,Layer (electronics) - Abstract
Hexagonal boron nitride (h-BN) has been highlighted as a promising low-dimensional material for thermal management of next-generation devices. The theory predicts that the thermal conductivity of h-BN increases above the bulk value as the thickness is reduced, but previous reports on few-layer (5–11 layer) h-BN have shown the opposite trend. We investigated the effect of isotopic engineering on the thermal properties of 11-layer h-BN single-crystal flakes. The thermal conductivities of natural (22% 10B, 78% 11B) and monoisotopic (99% 10B) h-BN were determined by a modified optothermal Raman method in the range 300–400 K. At room temperature, values were as high as (630 + 90/–65) Wm–1K–1 for monoisotopic h-10BN and (405 + 87/–65) Wm–1K–1 for natural h-BN, corresponding to an isotopic enhancement of close to 60%. Both measured thermal conductivities either match or exceed previously reported values for bulk crystals, while the isotopic enhancement factor is approximately 35% higher for the isotopically enriched thin crystal compared to the equivalent bulk materials. The work presented here demonstrates isotopic engineering as a viable route to increased thermal conductivity in atomically thin h-BN, making it an outstanding platform material for thermal management in next-generation device applications.
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- 2020
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32. Direct Endoscopic Necrosectomy With and Without Hydrogen Peroxide for Walled-off Pancreatic Necrosis: A Multicenter Comparative Study
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B. Joseph Elmunzer, Ahmed A. Messallam, Dan Mullady, Thomas Hollander, Qiang Cai, Satish Nagula, Chao Zhang, Nikhil A. Kumta, Linda J. Taylor, Madeleine Birch, Steven Tsistrakis, Steven Keilin, Michael Oliver M. Mercado, Field F. Willingham, Harkirat Singh, Samuel Han, Gregory A. Cote, Christopher J. DiMaio, Natalie Cosgrove, Robert A. Moran, Georgios I. Papachristou, Huma Javaid, Jose Nieto, Mohamed O. Othman, Douglas G. Adler, Raj J. Shah, and Nicolas LaBarre
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Male ,medicine.medical_specialty ,Necrosis ,Clinical success ,Endosonography ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Endoscopy, Digestive System ,Retrospective Studies ,Hepatology ,medicine.diagnostic_test ,Pancreatitis, Acute Necrotizing ,business.industry ,Gastroenterology ,Retrospective cohort study ,Hydrogen Peroxide ,Odds ratio ,Middle Aged ,medicine.disease ,Surgery ,Endoscopy ,Treatment modality ,030220 oncology & carcinogenesis ,Anti-Infective Agents, Local ,Drainage ,Pancreatitis ,Female ,030211 gastroenterology & hepatology ,medicine.symptom ,business ,Complication ,Follow-Up Studies - Abstract
Endoscopic necrosectomy has emerged as the preferred treatment modality for walled-off pancreatic necrosis. This study was designed to evaluate the safety and efficacy of direct endoscopic necrosectomy with and without hydrogen peroxide (H2O2) lavage.Retrospective chart reviews were performed for all patients undergoing endoscopic transmural management of walled-off pancreatic necrosis at 9 major medical centers from November 2011 to August 2018. Clinical success was defined as the resolution of the collection by imaging within 6 months, without requiring non-endoscopic procedures or surgery.Of 293 patients, 204 met the inclusion criteria. Technical and clinical success rates were 100% (204/204) and 81% (166/189), respectively. For patients, 122 (59.8%) patients had at least one H2O2 necrosectomy (H2O2 group) and 82 (40.2%) patients had standard endoscopic necrosectomy. Clinical success was higher in the H2O2 group: 106/113 (93.8%) vs 60/76 (78.9%), P = 0.002. On a multivariate analysis, the use of H2O2 was associated with higher clinical success rate (odds ratio 3.30, P = 0.033) and earlier resolution (odds ratio 2.27, P0.001). During a mean follow-up of 274 days, 27 complications occurred. Comparing procedures performed with and without H2O2 (n = 250 vs 183), there was no difference in post-procedure bleeding (7 vs 9, P = 0.25), perforation (2 vs 3, P = 0.66), infection (1 vs 2, P = 0.58), or overall complication rate (n = 13 [5.2%] vs 14 [7.7%], P = 0.30).H2O2-assisted endoscopic necrosectomy had a higher clinical success rate and a shorter time to resolution with equivalent complication rates relative to standard necrosectomy.See the visual abstract at http://links.lww.com/AJG/B714.(Equation is included in full-text article.).
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- 2020
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33. Design and Development of Electronic Sensor and Monitoring System of Smart Low-cost Phototherapy Light System for Non-Invasive Monitoring and Treatment of Neonatal Jaundice
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Neil Angelo M. Mercado, Paul M. Cabacungan, Gregory L. Tangonan, Carlos Oppus, Nerissa G. Cabacungan, and John Paul A. Mamaradlo
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medicine.medical_specialty ,Physics and Astronomy (miscellaneous) ,Computer science ,Management of Technology and Innovation ,Non invasive ,medicine ,Monitoring system ,Light system ,Jaundice ,medicine.symptom ,Intensive care medicine ,Engineering (miscellaneous) - Published
- 2020
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34. ESD with double-balloon endoluminal intervention platform versus standard ESD for management of colon polyps
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Mohamed O. Othman, Randa Habazi, Sahana Prabhu, Sharon John, Mohamed Saleh Ismail, Chandra Kovvali, Firas Bahdi, Michael Oliver M. Mercado, and Angel Alexander
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medicine.medical_specialty ,Original article ,business.industry ,Patient demographics ,Significant difference ,Polyp size ,Retrospective cohort study ,Balloon ,medicine.disease ,Surgery ,Colon polyps ,Resection ,medicine ,Referral center ,lcsh:Diseases of the digestive system. Gastroenterology ,Pharmacology (medical) ,lcsh:RC799-869 ,business - Abstract
Background and study aims Endoscopic submucosal dissection (ESD) with the double-balloon endoluminal intervention platform (DEIP) is a novel technique for removal of complex colon polyps (> 2 cm) or those located in anatomically difficult positions. DEIP helps create a therapeutic zone with improved visualization and stability, facilitating polyp removal. We aimed to compare the outcomes of DEIP with the conventional cap-assisted ESD (standard ESD) technique for colon polyp resection, in particular, the ability to complete the ESD procedure without resorting to hybrid ESD or piecemeal resection. Patients and methods This was a retrospective cohort of all patients who underwent colon ESD in a single large tertiary referral center between September 2016 and October 2019. Information was collected on patient demographics and study outcomes including procedure time, rates of en bloc and curative resection, operative and postoperative complications. All patients were followed up for 1 month after the procedure. Results 111 patients were included in the study (DEIP 60, standard ESD 51). There was no statistically significant difference between mean procedures time (± SD) in the two groups, mean (81.9 ± 35.4 min standard vs. 96.4 ± 42.2 min in DEIP). Mean polyp size (± SD) was similar between the two groups (7.6 ± 6.0 cm2 vs. 6.2 ± 5.5 cm2, P = .2). There were no significant differences in en bloc and curative resection rates or operative and postoperative complications between the two techniques. Conclusion Procedure time was similar using both techniques. However, DEIP enabled the entire procedure to be performed using the ESD technique without resorting to snare resection, which may affect the en bloc and curative resection rate. There were no significant differences in en bloc and curative resection rates between the two groups, probably due to the small sample size.
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- 2020
35. Biodiversity Distribution Patterns of Marine Phytoplankton and their Main Threats (Climate Change, Eutrophication and Acidification)
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Jesús M. Mercado and Soluna Salles
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business.industry ,Ecology ,Phytoplankton ,Biodiversity ,Distribution (economics) ,Climate change ,Environmental science ,Spatial variability ,business ,Eutrophication ,Cell mass - Published
- 2020
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36. Ecophysiology of Marine Algae
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Dolores Cortés, Jesús M. Mercado, and Soluna Salles
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Ecophysiology ,Algae ,biology ,Botany ,Environmental science ,Photosynthesis ,biology.organism_classification - Published
- 2020
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37. Influence of tissue thickness on thermal latency during high-power short-duration radiofrequency ablation with proactive esophageal cooling
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E Kulstad, M Mercado-Montoya, T Gomez-Bustamante, E Berjano, S Mickelsen, J Daniels, P Hernandez-Arango, and J Schieber
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Abstract
Funding Acknowledgements Type of funding sources: None. Background Thermal latency, or delayed heating, is increasingly recognized as an important factor in the formation of both intentional and unintentional lesions during radiofrequency (RF) ablation for the treatment of atrial fibrillation (AF). High-power short-duration (HPSD) ablation appears to have greater thermal latency than low or medium power ablation. Proactive esophageal cooling (PEC) has been shown to reduce esophageal lesion formation under a variety of conditions by directly reducing the effects of thermal latency, but the influence of anatomic dimensions on the protective efficacy of cooling during HPSD ablation has not been investigated. Purpose Determine the impact of changes in pericardial tissue thickness on thermal latency in order to quantify the protective efficacy of PEC across a range of anatomic dimensions. Methods We created a mathematical model of the left atrium undergoing HPSD ablation, both with and without a PEC device in place, using a range of pericardial tissue thicknesses (0.5, 0.75, and 1 mm). HPSD ablation was set at 50 W for 10 s, or 90 W for 4 s. We then examined the temperature dynamics at a range of thickness, focusing on the layer of mostly fatty tissue between the atrial and esophageal walls by varying the thickness of this layer while quantifying the degree of esophageal damage using the Arrhenius equation to determine the fraction of damage after peak heating has occurred. Results Under control conditions, the growth of lesions from RF ablation at both 50 W and 90 W was found to continue for greater than 10 seconds beyond the cessation of RF energy application. Esophageal lesion formation ranged from 71% to 96% transmurality after 50 W ablation for 10 s, and from 50% to 72% transmurality after 90 W ablation for 4 s. With PEC in place, esophageal lesion transmurality was markedly reduced, with a maximum transmurality ranging from 12% to 32% with 50 W ablation, and from 2% to 20% with 90 W ablation (Figure). Increasing thickness of pericardial tissue (with simulations of 0.5, 0.75, and 1 mm) resulted in decreasing esophageal lesion transmurality (67%, 74%, and 83% at 50 W power, and 72%, 82%, and 96% at 90 W power, respectively, with the 0.5, 0.75, and 1 mm simulations). Conclusions Thermal latency with HPSD ablation contributes to lesion growth and can cause esophageal injury. Proactive esophageal cooling counteracts this effect across a range of pericardial tissue thicknesses, and reduces esophageal lesion transmurality by an average of 79%.
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- 2022
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38. Supplementary material to 'The ozone–climate penalty over South America and Africa by 2100'
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Flossie Brown, Gerd A. Folberth, Stephen Sitch, Susanne Bauer, Marijin Bauters, Pascal Boeckx, Alexander W. Cheesman, Makoto Deushi, Inês Dos Santos, Corinne Galy-Lacaux, James Haywood, James Keeble, Lina M. Mercado, Fiona M. O'Connor, Naga Oshima, Kostas Tsigaridis, and Hans Verbeeck
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- 2022
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39. Reduced global fire activity due to human demography slows global warming by enhanced land carbon uptake
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Chao Wu, Stephen Sitch, Chris Huntingford, Lina M. Mercado, Sergey Venevsky, Gitta Lasslop, Sally Archibald, and A. Carla Staver
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Multidisciplinary ,Meteorology and Climatology ,Climate Change ,Humans ,Carbon Dioxide ,Global Warming ,Carbon ,Ecosystem ,Fires ,Demography - Abstract
Fire is an important climate-driven disturbance in terrestrial ecosystems, also modulated by human ignitions or fire suppression. Changes in fire emissions can feed back on the global carbon cycle, but whether the trajectories of changing fire activity will exacerbate or attenuate climate change is poorly understood. Here, we quantify fire dynamics under historical and future climate and human demography using a coupled global climate–fire–carbon cycle model that emulates 34 individual Earth system models (ESMs). Results are compared with counterfactual worlds, one with a constant preindustrial fire regime and another without fire. Although uncertainty in projected fire effects is large and depends on ESM, socioeconomic trajectory, and emissions scenario, we find that changes in human demography tend to suppress global fire activity, keeping more carbon within terrestrial ecosystems and attenuating warming. Globally, changes in fire have acted to warm climate throughout most of the 20th century. However, recent and predicted future reductions in fire activity may reverse this, enhancing land carbon uptake and corresponding to offsetting ∼5 to 10 y of global CO2 emissions at today’s levels. This potentially reduces warming by up to 0.11 °C by 2100. We show that climate–carbon cycle feedbacks, as caused by changing fire regimes, are most effective at slowing global warming under lower emission scenarios. Our study highlights that ignitions and active and passive fire suppression can be as important in driving future fire regimes as changes in climate, although with some risk of more extreme fires regionally and with implications for other ecosystem functions in fire-dependent ecosystems.
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- 2022
40. Nocturnal plant respiration is under strong non-temperature control
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Dan Bruhn, Freya Newman, Mathilda Hancock, Peter Povlsen, Martijn Slot, Stephen Sitch, John Drake, Graham P. Weedon, Douglas B. Clark, Majken Pagter, Richard J. Ellis, Mark G. Tjoelker, Kelly M. Andersen, Zorayda Restrepo Correa, Patrick C. McGuire, and Lina M. Mercado
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Plant Leaves ,Multidisciplinary ,Respiration ,Temperature ,General Physics and Astronomy ,General Chemistry ,Carbon Dioxide ,Plants ,Ecology and Environment ,General Biochemistry, Genetics and Molecular Biology ,Ecosystem ,Trees - Abstract
Most biological rates depend on the rate of respiration. Temperature variation is typically considered the main driver of daily plant respiration rates, assuming a constant daily respiration rate at a set temperature. Here, we show empirical data from 31 species from temperate and tropical biomes to demonstrate that the rate of plant respiration at a constant temperature decreases monotonically with time through the night, on average by 25% after 8 h of darkness. Temperature controls less than half of the total nocturnal variation in respiration. A new universal formulation is developed to model and understand nocturnal plant respiration, combining the nocturnal decrease in the rate of plant respiration at constant temperature with the decrease in plant respiration according to the temperature sensitivity. Application of the new formulation shows a global reduction of 4.5 −6 % in plant respiration and an increase of 7-10% in net primary production for the present-day.
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- 2022
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41. How to boost the effects of exercise to favor traumatic brain injury outcome
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Fernando Gomez-Pinilla and Natosha M. Mercado
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Physical Therapy, Sports Therapy and Rehabilitation ,Orthopedics and Sports Medicine - Abstract
Physical rehabilitation is an effective therapy to normalize weaknesses encountered with neurological disorders such as traumatic brain injury (TBI). However, the efficacy of exercise is limited during the acute period of TBI because of metabolic dysfunction, and this may further compromise neuronal function. Here we discuss the possibility to normalize brain metabolism during the early post-injury convalescence period to support functional plasticity and prevent long-term functional deficits. Although BDNF possesses the unique ability to support molecular events involved with the transmission of information across nerve cells through activation of its TrkB receptor, the poor pharmacokinetic profile of BDNF has limited its therapeutic applicability. The flavonoid derivative, 7,8-dihydroxyflavone (7,8-DHF), signals through the same TrkB receptors and results in the activation of BDNF signaling pathways. We discuss how the pharmacokinetic limitations of BDNF may be avoided by the use of 7,8-DHF, which makes it a promising pharmacological agent for supporting activity-based rehabilitation during the acute post-injury period after TBI. In turn, docosahexaenoic acid (C22:6n-3; DHA) is abundant in the phospholipid composition of plasma membranes in the brain and its action is important for brain development and plasticity. DHA is a major modulator of synaptic membrane fluidity and function, which is fundamental for supporting cell signaling and synaptic plasticity. Exercise influences DHA function by normalizing DHA content in the brain, such that the collaborative action of exercise and DHA can be instrumental to boost BDNF function with strong therapeutic potential for reducing the deleterious effects of TBI on synaptic plasticity and cognition.
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- 2022
42. NEXT-GENERATION SEQUENCING MUTATIONAL ANALYSIS OF CELL-FREE DNA IN ERCP-OBTAINED BILE. A STEP FORWARD IN THE DIAGNOSIS OF MALIGNANT BILIARY STENOSIS
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M. Rullan, D. Oyon, L. Zabalza, P. Salmón, V. Jusué, M. Mercado, B. González de la Higuera, I. Amat, J. Carrascosa, I. Fernández-Urien, D. Ruiz-Clavijo, M. Casi, E. Borobio, C. Saldaña, F. Bolado, M. Arechederra, C. Berasain, M.A Avila, J.M Urman, and J.J. Vila
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- 2022
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43. A short-term method to evaluate anti-leishmania drugs by inhibition of stage differentiation in Leishmania mexicana using flow cytometry
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Christian Florian Teh-Poot, Victor Manuel Dzul-Huchim, Jonathan M. Mercado, Liliana Estefanía Villanueva-Lizama, Maria Elena Bottazzi, Kathryn M. Jones, Francis T.F. Tsai, and Julio Vladimir Cruz-Chan
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Infectious Diseases ,Immunology ,Parasitology ,General Medicine - Published
- 2023
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44. Data for: Modelling the impact of wood density dependent tree mortality on the spatial distribution of Amazonian vegetation carbon
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Mathilda Hancock, Stephen Sitch, Fabian J. Fischer, Jérôme Chave, Michael O'Sullivan, Dominic Fawcett, and Lina M. Mercado
- Abstract
Description of the supplementary data used by "Modelling the impact of wood density dependent tree mortality on the spatial distribution of Amazonian vegetation carbon" by Hancock et al. submitted March 2022. Included in this repository are: 1. The kriged map of wood density. The source data for the kriging was from 414 intact RAINFOR and ATDN plots, from Mitchard et al. (2014) 2. The 12 mortality gridded fields, input to JULES as ancillary data and derived from wood density. 3. Present day JULES model outputs for each mortality configuration., {"references":["Mitchard, E. T., Feldpausch, T. R., Brienen, R. J., Lopez-Gonzalez, G., Monteagudo, A., Baker, T. R., Lewis, S. L., Lloyd, J., Quesada, C. A., Gloor, M., et al.: Markedly divergent estimates of Amazon forest carbon density from ground plots and satellites, Global Ecol. Biogeogr., 23, 935–946, https://doi.org/10.1111/geb.12168, 2014"]}
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- 2022
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45. Spatio-temporal variability of the zooplankton community in the SW Mediterranean 1992–2020: Linkages with environmental drivers
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Lidia Yebra, Marta Puerto, Nerea Valcárcel-Pérez, Sébastien Putzeys, Francisco Gómez-Jakobsen, Candela García-Gómez, and Jesús M. Mercado
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zooplankton ,predators ,Taxonomic composition ,variability ,Zooplankton time series ,Mesozooplankton abundance ,Geology ,Aquatic Science ,Alboran Sea ,zooplankton abundance ,Centro Oceanográfico de Málaga ,SW Mediterranean ,taxa ,environmental drivers ,time series ,Medio Marino ,oceanography ,surface circulation ,nauplii - Abstract
Variability in the spatial and temporal distribution of the mesozooplankton abundance in the N Alboran Sea (SW Mediterranean) was assessed intermittently from 2010 to 2020, and compared with 1992-2000 historical time series data. Total abundance of mesozooplankton was significantly higher in the coast than in the shelf and slope waters. There were significant differences in mesozooplankton abundance between 1992-2000 and 2010-2020 at the three zones. Copepods dominated the mesozooplankton during winter and spring, but cladocerans and doliolids also became important components of the community in summer and autumn. We found significant increases between the first and the second decadal periods in the abundance of copepods, appendicularians, holoplanktonic gastropods and siphonophores in the shelf. However, in the coast, copepod nauplii, doliolids, gastropods and siphonophores increased, while euphausiids abundance decreased significantly. These trends contrast with the ongoing decline of the sardine stocks in European waters. Increasing temperature and decreasing predation pressure are suggested to be the main drivers of mesozooplankton variability., 3 ESMAREU, 2-3 ESMAREU, 10-ESMARESC4A2, MICROZOO-ID, Spanish Ministry of Agriculture, Food and Environment; Spanish Institute of Oceanography (IEO, CSIC); Andalusian Government (Consejería de Economía, Innovación y Ciencia de la Junta de Andalucía) and EU (Fondo Europeo de Desarrollo Regional)
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- 2022
46. Supplementary material to 'Improved representation of plant physiology in the JULES-vn5.6 land surface model: Photosynthesis, stomatal conductance and thermal acclimation'
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Rebecca J. Oliver, Lina M. Mercado, Doug B. Clark, Chris Huntingford, Christopher M. Taylor, Pier Luigi Vidale, Patrick C. McGuire, Markus Todt, Sonja Folwell, Valiyaveetil Shamsudheen Semeena, and Belinda E. Medlyn
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- 2022
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47. Atomic Structure of the Leishmania spp. Hsp100 N-Domain
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Jonathan M. Mercado, Sukyeong Lee, Changsoo Chang, Nuri Sung, Lynn Soong, Andre Catic, and Francis T. F. Tsai
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Leishmania ,Binding Sites ,Structural Biology ,Humans ,Peptides ,Molecular Biology ,Biochemistry ,Article ,Heat-Shock Proteins ,Molecular Chaperones - Abstract
Hsp100 is an ATP-dependent unfoldase that promotes protein disaggregation or facilitates the unfolding of aggregation-prone polypeptides marked for degradation. Recently, new Hsp100 functions are emerging. In Plasmodium, an Hsp100 drives malaria protein export, presenting a novel drug target. Whether Hsp100 has a similar function in other protists is unknown. We present the 1.06 Å resolution crystal structure of the Hsp100 N-domain from Leishmania spp., the causative agent of leishmaniasis in humans. Our structure reveals a network of methionines and aromatic amino acids that define the putative substrate-binding site and likely evolved to protect Hsp100 from oxidative damage in host immune cells.
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- 2022
48. Examining Ozone Sensitivity in the Genus Musa (Bananas)
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Mst Nahid Farha, Jeff Daniells, Lucas A. Cernusak, Edita Ritmejerytė, Phurpa Wangchuk, Stephen Sitch, Lina M. Mercado, Felicity Hayes, Flossie Brown, and Alexander W. Cheesman
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
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49. Seasonal variability in phytoplankton light absorption properties: Implications for the regional parameterization of the chlorophyll a specific absorption coefficients
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Jesús M. Mercado and Francisco Gómez-Jakobsen
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Chlorophyll ,Chlorophyll a ,Absorption spectroscopy ,absorption spectra ,spectra ,Temperature salinity diagrams ,Aquatic Science ,Oceanography ,Atmospheric sciences ,diatoms ,chemistry.chemical_compound ,Mediterranean sea ,Water column ,Phytoplankton ,Photic zone ,Medio Marino ,Absorption (electromagnetic radiation) ,Primary production ,Geology ,parameterization ,chemistry ,Centro Oceanográfico de Málaga ,light absorption ,Environmental science ,Bio-optical properties - Abstract
Data of in vivo absorption of particulate material in water column obtained from multiple research cruises performed in the Alboran Sea (Western Mediterranean Sea) were used to investigate seasonal variability of the phytoplankton light absorption properties Specific absorption coefficients of phytoplankton, a_ph^*() were calculated and used to determine the performance of a_ph^*() parameterizations based on chlorophyll a concentration for each season. a_ph^*() in the blue spectral bands for the euphotic layer decreased by 20% in spring and summer compared with autumn and winter. These changes might reflect stronger dominance of diatoms during these periods, since these cells are characterized by a high degree of pigment packaging that leads to flattening of the absorption spectrum. Surface temperature and salinity, which are proxies for modifications of the surface layer by vertical mixing, explained more than 50% of the variability in the absorption properties, suggesting that the communities also presented high photo-acclimation capacity in response to short-term hydrological variability. The biases between measured and parameterized a_ph^*() decreased when the seasonal relationships between chlorophyll a concentration and a_ph^*() were used for estimating the parameterization coefficients instead of using the whole dataset. The regional parameterization using seasonal data performed better that parameterizations using global data. These seasonal and regional parameterizations can be useful for developing more refined bio-optical models of primary production for the study area, although it has to be taken into account that a significant percentage of variability in a_ph^*() related to short-term hydrological changes remained still unexplained by the seasonal parameterization., SI
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- 2022
50. Phytoplankton Dynamics in the Mar Menor, a Mediterranean Coastal Lagoon Strongly Impacted by Eutrophication
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Sophia Ouaissa, Francisco Gómez-Jakobsen, Lidia Yebra, Isabel Ferrera, Enrique Moreno-Ostos, María Dolores Belando, Juan M. Ruiz, and Jesús M. Mercado
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Aquatic Science ,Oceanography ,Pollution - Published
- 2022
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