42 results on '"Serrano, Oscar"'
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2. Radically different lignin composition in Posidonia species may link to differences in organic carbon sequestration capacity.
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Kaal, Joeri, Serrano, Oscar, del Río, José C., and Rencoret, Jorge
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POSIDONIA australis , *POSIDONIA oceanica , *LIGNINS , *CARBON sequestration , *HYDROXYBENZOATES - Abstract
Highlights • Molecular composition of Posidonia oceanica and P. australis seagrasses compared. • Lignin of P. oceanica has an extraordinary abundance of p -hydroxybenzoic acid. • p -hydroxybenzoates attach to the γ-OH of the lignin side-chains. • Lignin composition may explain higher carbon storage capacity of P. oceanica. Abstract There is considerable variability in the ability of seagrass ecosystems to sequester organic carbon (C org) in their sediments, which act as natural carbon sinks contributing to climate change mitigation. In this work, we studied the chemistry of two Posidonia seagrass species aiming to elucidate whether differences in chemical composition might explain differences in their C org sequestration capacity. Pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) and Thermally assisted Hydrolysis and Methylation (THM) GC-MS data showed a remarkable difference in phenolic compound patterns between P. oceanica and P. australis bulk plants and individual organs (leaves, sheaths, roots and rhizomes). The lignin of P. australis generates a series of p -hydroxyphenyl (H), guaiacyl (G) and syringyl (S) products that are typical of herbaceous plants, whereas P. oceanica is particularly rich in p -hydroxybenzoic acid (p BA) derivatives. The structural characteristics of the lignins were further investigated by two-dimensional Nuclear Magnetic Resonance (2D-NMR) spectroscopy and Derivatization Followed by Reductive Cleavage (DFRC), focusing on sheath tissues. The analyses confirmed important differences in the lignin content (19.8% in P. australis and 29.5% in P. oceanica) and composition between the two species; intriguingly, the cell-walls of P. oceanica sheaths were highly enriched in p BA, a component that was completely absent in P. australis. 2D-NMR and DFRC data further revealed that p BA was esterified to the lignin, acylating the γ-OH of the lignin side-chain. Interestingly, P. oceanica lignin presented an extremely high degree of p -hydroxybenzoylation in both guaiacyl (73%) and syringyl (61%) lignin units; the highest p -hydroxybenzoylation degree reported in plant lignins to date. It is tempting to conclude that the higher C org storage capacity of P. oceanica ecosystems might be related to the higher abundance of p BA-rich lignin and its recalcitrant nature. [ABSTRACT FROM AUTHOR]
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- 2018
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3. Post-Transplant Malignancy after Pediatric Kidney Transplantation: Retrospective Analysis of Incidence and Risk Factors in 884 Patients Receiving Transplants Between 1963 and 2015 at the University of Minnesota.
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Serrano, Oscar K., Chinnakotla, Srinath, Dunn, Ty B., Finger, Erik B., Kandaswamy, Raja, Pruett, Timothy L., Najarian, John S., Matas, Arthur J., Bangdiwala, Ananta S., Vock, David M., and Chavers, Blanche M.
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COMPLICATIONS from organ transplantation , *KIDNEY transplantation , *TRANSPLANTATION of organs, tissues, etc. in children , *AZATHIOPRINE , *CANCER - Abstract
Background: Post-transplant malignancy (PTM) remains a concern among pediatric kidney transplant (PKT) recipients.Study Design: Between 1963 and 2015, 884 pediatric (age 0 to 17 years old) patients received 1,055 PKTs at our institution. Cox proportional hazards models were constructed to identify risk factors for PTM after PKT with time-to-first-PTM as a primary outcome. Secondly, the hazard of death or graft loss was calculated in patients who developed PTM.Results: Median patient survival was 33 years (interquartile range [IQR] 18.7 to 47 years); 260 patients died during the study period and 47 had been diagnosed with PTM. There were 235 PTMs that occurred in 136 (15.4%) recipients at a median age of 29 years (IQR 17.8 to 37 years). The percentages of patients with PTM were 13% at 20 years post-PKT and 26% at 30 years post-PKT. Of PTM patients who died, 63.8% died of PTM. Among those who developed PTM, there was a higher hazard of death or graft loss (hazard ratio [HR] 1.62; 95% CI 1.11 to 2.38). In multivariable proportional hazards models, factors associated with PTM were increasing age at PKT (adjusted HR [AHR] 3.14; 95% CI 1.80 to 5.48 for 14 to 17 year-olds compared with children less than 3 years), having a living unrelated donor (LURD; AHR 3.25; 95% CI 1.27 to 8.35 compared with a living related donor), or implanting an Epstein-Barr virus (EBV)-positive allograft in an EBV-negative recipient (AHR 5.66; 95% CI 1.11 to 29.0). Compared with the general population, the cancer rate for PKT recipients was 6 times higher (126 vs 21 per 100,000 person-years).Conclusions: Pediatric kidney transplant recipients are at increased risk of PTM, which adversely affects survival. Children receiving transplants at an older age, from a LURD, or who receive an EBV-positive organ, should be monitored closely for the development of PTM. [ABSTRACT FROM AUTHOR]- Published
- 2017
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4. Review of the physical and chemical properties of seagrass soils.
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Piñeiro-Juncal, Nerea, Serrano, Oscar, Mateo, Miguel Ángel, Diaz-Almela, Elena, Leiva-Dueñas, Carmen, and Martinez-Cortizas, Antonio
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POSIDONIA , *SEAGRASSES , *CHEMICAL properties , *MARINE sediments , *SOIL science , *SOIL color , *CONTINENTS - Abstract
• Seagrass soils have been neglected in soil science but widely studied as sediments. • Published values for the main seagrass soil characteristics have been gathered. • Soil seagrass data is biased towards temperate species and high-income countries. • Soils under persistent seagrass species showed higher organic carbon and sandier textures. • Seagrass biological traits drive differences in soil physical and chemical properties. Seagrasses are a polyphyletic group of angiosperms that colonized marine environments more than 30 million years ago and currently inhabit coastal soft and rocky substrates in all continents except Antarctica. Due to their evolution from terrestrial plants, seagrasses have belowground organs that interact with the substrate, transforming it through chemo-physical processes analogous to terrestrial soil formation. Although seagrass substrates provide valuable ecosystem services including carbon and coastal stabilization, they have been largely regarded as sediments by marine scientists and neglected in soil science research. However, over the last decades, the increasing interest in carbon accumulation by seagrasses has generated multiple data on seagrass soil physical and chemical characteristics. Here, we review clay and silt content (<0.063 mm particle size), redox potential, pH, carbonate content, organic carbon or organic matter contents, dry bulk density, porosity and color of seagrass soils worldwide, summarizing data typically used for soil description, and looking for generalities in soil characteristics across seagrass habitats. The data gathered was biased towards temperate species and high-income countries, while data about color, porosity, redox potential and pH was scarce. Soil characteristics did not show significant differences among seagrass bioregions. Most seagrass substrates showed sandy textures, whereas one of the most sampled genera, Posidonia , was not present in muddy substrates. The soil C org content was significantly higher in meadows formed by persistent species (mean ± SD; 1.76 ± 2.17 %) than in meadows formed by species with opportunistic and colonizing life-strategies (1.52 ± 2.24 and 0.76 ± 0.95 %, respectively), while mud content was significantly higher in meadows formed by opportunistic and colonizing species (27.87 ± 29.58 and 21.23 ± 21.77 %, respectively) than in those formed by persistent species (11.83 ± 14.45 %). Redox potential was significantly lower in intertidal than in subtidal meadows, although caution is needed when interpreting these differences due to methodological limitations. This review provides an overview of current knowledge on seagrass soil characteristics, while identifying knowledge gaps in seagrass soil science, including geographical, species diversity and soil physico-chemical traits that limit our capacity to characterize and classify seagrass soils worldwide. [ABSTRACT FROM AUTHOR]
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- 2022
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5. Molecular composition of plant parts and sediment organic matter in a Mediterranean seagrass (Posidonia oceanica) mat.
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Kaal, Joeri, Serrano, Oscar, Nierop, Klaas G.J., Schellekens, Judith, Martínez Cortizas, Antonio, and Mateo, Miguel-Ángel
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POSIDONIA oceanica , *SEAGRASSES , *CHEMICAL composition of plants , *DETRITUS , *MICROBIAL mats , *PYROLYSIS , *GLOBAL environmental change - Abstract
Posidonia oceanica forms extensive peat-like deposits (mats) in Mediterranean coastal waters, which have a potential as carbon sinks and archives of environmental change. Nonetheless, the organic chemistry of both P. oceanica plant materials, as well as the environmental and diagenetic effects on the composition of its detritus, is poorly understood. We analyzed plant organs of P. oceanica and the coarse organic matter from a mat core spanning 750 yrs using pyrolysis techniques (PY-GC–MS and THM-GC–MS) to improve our understanding of their molecular properties and their preservation upon mat development. It appeared that leaf sheaths, roots and the outer parts of rhizomes were composed predominantly of phenolic constituents based on p -hydroxybenzoic acid ( p -HBA), which is atypical for vascular plants, in addition to carbohydrates and lignin. The inner rhizome and leaf blades had a different composition, with predominance of carbohydrates. The seagrass detritus in the mat was composed mainly of p -HBA phenolic material and carbohydrates, confirming earlier studies showing that the coarse detritus in the mat originates largely from Posidonia sheath, root and rhizome debris. The intermolecular arrangement of the p -HBA remains unclear, as they seem to correspond to ester-bound phenols yet their persistence in the mat attributes them a refractory nature. Variations in molecular composition within the mat are probably associated with diagenetic alteration of P. oceanica detritus, such as the decomposition of minor amounts of fatty acids, chlorophyll and syringyl lignin, and selective preservation of p -HBA relative to carbohydrates. This work lays the foundations for a molecular understanding of carbon storage within the mats and the environmental changes recorded therein. [ABSTRACT FROM AUTHOR]
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- 2016
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6. Excess Weight Loss and Cardiometabolic Parameter Reduction Diminished among Hispanics Undergoing Bariatric Surgery: Outcomes in More than 2,000 Consecutive Hispanic Patients at a Single Institution.
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Serrano, Oscar K., Zhang, Yang, Cumella, Lindsay, Kintzer, Emily, Ng, Nicole, Sandoval, Eduardo, Choi, Jenny, Melvin, W. Scott, and Camacho, Diego R.
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WEIGHT loss , *BARIATRIC surgery , *OBESITY treatment , *HEALTH outcome assessment , *GASTRIC bypass , *LAPAROSCOPY , *GASTRECTOMY , *HISPANIC Americans , *RESEARCH funding , *STOMACH surgery , *MORBID obesity , *BODY mass index , *TREATMENT effectiveness , *RETROSPECTIVE studies - Abstract
Background: Bariatric surgery has been established as the most effective long-term treatment for morbid obesity and obesity-related comorbidities. Despite its success, there is a paucity of data on the outcomes of bariatric surgery on Hispanic patients.Study Design: We performed a retrospective review of obese patients treated at our institute between 2008 and 2014. We identified self-reported Hispanic patients who underwent a laparoscopic gastric bypass (LGBP), sleeve gastrectomy (LSG), or gastric band (LGB) procedure. The primary end point was excess weight loss (EWL) at 6, 12, 24, and 36 months. Secondary end points included improvement of obesity-related metabolic parameters at 1 year. We performed a repeated measures analysis of variance to calculate statistical significance throughout our study time period.Results: We identified 2002 Hispanic patients who underwent bariatric surgery (1,235 LGBP, 600 LSG, 167 LGB) at our institute from 2008 to 2014. Follow-ups at 6, 12, 24, and 36 months were 62.2%, 54.5%, 36.2%, and 19.8%, respectively. Mean preoperative BMIs were 47.0 ± 7.2 kg/m2, 46.1 ± 7.8 kg/m2, and 44.9 ± 6.0 kg/m2 for the LGBP, LSG, and LGB cohorts, respectively. Excess weight loss was significantly more pronounced in the LGBP and the LSG groups than in the LGB group; this difference was accentuated over time (p < 0.0001). Obesity-related metabolic parameters and the need for comorbidity medical therapy decreased in all 3 surgical groups.Conclusions: Bariatric surgery is highly successful in Hispanic obese patients. In the largest series to date, LGBP and LSG seem to yield more effective EWL and reduction of cardiometabolic parameters than LGB among Hispanics; however, outcomes are still markedly reduced when compared with those in non-Hispanic populations. [ABSTRACT FROM AUTHOR]- Published
- 2016
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7. Reconstruction of centennial-scale fluxes of chemical elements in the Australian coastal environment using seagrass archives.
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Serrano, Oscar, Davis, Grace, Lavery, Paul S., Duarte, Carlos M., Martinez-Cortizas, Antonio, Mateo, Miguel Angel, Masqué, Pere, Arias-Ortiz, Ariane, Rozaimi, Mohammad, and Kendrick, Gary A.
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POSIDONIA australis , *SEAGRASSES , *CHEMICAL elements , *COASTS , *MARINE ecology , *BIOGEOCHEMICAL cycles , *HOLOCENE Epoch - Abstract
The study of a Posidonia australis sedimentary archive has provided a record of changes in element concentrations (Al, Fe, Mn, Pb, Zn, Cr, Cd, Co, As, Cu, Ni and S) over the last 3000 years in the Australian marine environment. Human-derived contamination in Oyster Harbor (SW Australia) started ~ 100 years ago (AD ~ 1900) and exponentially increased until present. This appears to be related to European colonization of Australia and the subsequent impact of human activities, namely mining, coal and metal production, and extensive agriculture. Two contamination periods of different magnitude have been identified: Expansion period (EXP, AD ~ 1900–1970) and Establishment period (EST, AD ~ 1970 to present). Enrichments of chemical elements with respect to baseline concentrations (in samples older than ~ 115 cal years BP) were found for all elements studied in both periods, except for Ni, As and S. The highest enrichment factors were obtained for the EST period (ranging from 1.3-fold increase in Cu to 7.2-fold in Zn concentrations) compared to the EXP period (1.1-fold increase for Cu and Cr to 2.4-fold increase for Pb). Zinc, Pb, Mn and Co concentrations during both periods were 2- to 7-fold higher than baseline levels. This study demonstrates the value of Posidonia mats as long-term archives of element concentrations and trends in coastal ecosystems. We also provide preliminary evidence on the potential for Posidonia meadows to act as significant long-term biogeochemical sinks of chemical elements. [ABSTRACT FROM AUTHOR]
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- 2016
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8. Antitumor effect of pharmacologic ascorbate in the B16 murine melanoma model.
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Serrano, Oscar K., Parrow, Nermi L., Violet, Pierre-Christian, Yang, Jacqueline, Zornjak, Jennifer, Basseville, Agnes, and Levine, Mark
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ANTINEOPLASTIC agents , *THERAPEUTIC use of vitamin C , *MELANOMA treatment , *SURVIVAL analysis (Biometry) , *CANCER chemotherapy , *PHARMACODYNAMICS , *ANIMAL models in research - Abstract
Because 5-year survival rates for patients with metastatic melanoma remain below 25%, there is continued need for new therapeutic approaches. For some tumors, pharmacologic ascorbate treatment may have a beneficial antitumor effect and may work synergistically with standard chemotherapeutics. To investigate this possibility in melanoma, we examined the effect of pharmacologic ascorbate on B16-F10 cells. Murine models were employed to compare tumor size following treatment with ascorbate, and the chemotherapeutic agents dacarbazine or valproic acid, alone or in combination with ascorbate. Results indicated that nearly all melanoma cell lines were susceptible to ascorbate-mediated cytotoxicity. Compared to saline controls, pharmacologic ascorbate decreased tumor size in both C57BL/6 ( P <0.0001) and NOD- scid tumor bearing mice ( P <0.0001). Pharmacologic ascorbate was superior or equivalent to dacarbazine as an antitumor agent. Synergy was not apparent when ascorbate was combined with either dacarbazine or valproic acid; the latter combination may have additional toxicities. Pharmacologic ascorbate induced DNA damage in melanoma cells, as evidenced by increased phosphorylation of the histone variant, H2A.X. Differences were not evident in tumor samples from C57BL/6 mice treated with pharmacologic ascorbate compared to tumors from saline-treated controls. Together, these results suggest that pharmacologic ascorbate has a cytotoxic effect against melanoma that is largely independent of lymphocytic immune functions and that continued investigation of pharmacologic ascorbate in cancer treatment is warranted. [ABSTRACT FROM AUTHOR]
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- 2015
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9. Glomalin accumulated in seagrass sediments reveals past alterations in soil quality due to land-use change.
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López-Merino, Lourdes, Serrano, Oscar, Adame, María Fernanda, Mateo, Miguel Ángel, and Martínez Cortizas, Antonio
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SOIL quality , *TOTAL suspended solids , *ENVIRONMENTAL protection , *AGRICULTURE , *SILVOPASTORAL systems - Abstract
Arbuscular mycorrhizal fungi (AMF), symbionts with most terrestrial plants, produce glomalin-related soil protein (GRSP), which plays a major role in soil structure and quality. Both fungi hyphae and protein production in soils are affected by perturbations related to land-use changes, implying that GRSP is a sensitive indicator of soil quality. Unfortunately, GRSP degrades within years to decades in oxic environments, preventing its use as palaeoecological proxy. However, GRSP is transported to marine, near-shore anoxic sediments, where it accumulates and remains non-degraded, enabling the assessment of its potential as a palaeoecological proxy for soil ecosystem's health. Exploiting this fact, we have obtained for the first time a long-term record (c. 1250 years) of GRSP content using a Posidonia oceanica seagrass mat sediment core from the Western Mediterranean (Portlligat Bay, Spain). The trends in GRSP content matched well with land-use changes related to agrarian activities reconstructed by pollen analysis. In periods of cultivation, GRSP accumulation in the mat decreased. Given the role played by GRSP, the results suggest that agrarian intensification may have resulted in perturbations to soil quality. Thus, GRSP in seagrass mat sediments can be used to assess long-term trends in continental soil quality induced by human activities. These findings open new possibilities in long-term ecology research, as other anoxic environments could be potentially valid too. Testing them would open the possibility to identify long-term patterns in soil quality and other environmental stressors that could also affect AMF and GRSP production in soils. [ABSTRACT FROM AUTHOR]
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- 2015
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10. National scale predictions of contemporary and future blue carbon storage.
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Young, Mary A., Serrano, Oscar, Macreadie, Peter I., Lovelock, Catherine E., Carnell, Paul, and Ierodiaconou, Daniel
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- 2021
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11. Acid washing effect on elemental and isotopic composition of whole beach arthropods: Implications for food web studies using stable isotopes
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Serrano, Oscar, Serrano, Laura, Mateo, Miguel Angel, Colombini, Isabella, Chelazzi, Lorenzo, Gagnarli, Elena, and Fallaci, Mario
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ARTHROPODA , *FOOD chains , *ISOTOPES , *ACIDIFICATION - Abstract
Abstract: Inorganic carbon removal through acidification is a common practice prior to isotopic analysis of macroinvertebrate samples. We have experimentally tested the effect of acidification on the elemental and isotopic composition of a range of beach arthropod species. Acidification resulted in a significant depletion of 7.7% and 1.2% on average for carbon and nitrogen, respectively, suggesting that acid washing affects body carbon compounds other than carbonates. With a few exceptions, δ13C and δ15N showed no changes following 1N HCl attack. Based on those exceptions, our results show that only those samples with a high CaCO3 content result in impoverished 13C as a consequence of acidification. Those suspected to be carbonate-free are not significantly affected. Concerning δ15N values, only high carbonate species were affected when treated with HCl. As a standard protocol, it is recommended to acidify only carbonate-rich samples prior to δ13C analyses. When possible, muscle tissue samples should be used instead of the entire organism. [Copyright &y& Elsevier]
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- 2008
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12. A semi-supervised autoencoder framework for joint generation and classification of breathing.
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Pastor-Serrano, Oscar, Lathouwers, Danny, and Perkó, Zoltán
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COMPUTER-aided diagnosis , *CONVOLUTIONAL neural networks , *RESPIRATION , *ALGORITHMS , *TIME series analysis - Abstract
• Models of breathing motion using 1D convolutional neural networks and probabilistic autoencoders. • A novel semi-supervised algorithm based on Adversarial Autoencoders that allows joint classification and generation of breathing. • The models are trained with 4% and 12% of the labeled data and achieve a macro F1-score of 94.91% and 96.54% in a different test set. • A pre-processing step compresses 3-dimensional breathing time series into vectors. One of the main problems with biomedical signals is the limited amount of patient-specific data and the significant amount of time needed to record the sufficient number of samples needed for diagnostic and treatment purposes. In this study, we present a framework to simultaneously generate and classify biomedical time series based on a modified Adversarial Autoencoder (AAE) algorithm and one-dimensional convolutions. Our work is based on breathing time series, with specific motivation to capture breathing motion during radiotherapy lung cancer treatments. First, we explore the potential in using the Variational Autoencoder (VAE) and AAE algorithms to model breathing signals from individual patients. We then extend the AAE algorithm to allow joint semi-supervised classification and generation of different types of signals within a single framework. To simplify the modeling task, we introduce a pre-processing and post-processing compressing algorithm that transforms the multi-dimensional time series into vectors containing time and position values, which are transformed back into time series through an additional neural network. The resulting models are able to generate realistic and varied samples of breathing. By incorporating 4% and 12% of the labeled samples during training, our model outperforms other purely discriminative networks in classifying breathing baseline shift irregularities from a dataset completely different from the training set, achieving an average macro F1-score of 94.91 % and 96.54 % , respectively. To our knowledge, the presented framework is the first approach that unifies generation and classification within a single model for this type of biomedical data, enabling both computer aided diagnosis and augmentation of labeled samples within a single framework. [ABSTRACT FROM AUTHOR]
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- 2021
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13. Effects of sample pre-treatment on the δ 13C and δ 18O values of living benthic foraminifera
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Serrano, Oscar, Serrano, Laura, and Mateo, Miguel Angel
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FORAMINIFERA , *CARBON isotopes , *OXYGEN isotopes , *HYDROGEN peroxide , *OXIDATION - Abstract
Abstract: Stable carbon and oxygen isotope ratios (δ 13C and δ 18O) of the epibenthic foraminiferan Elphidium macellum var. aculeatum were measured and compared both in raw aliquots and after various pre-analytical treatments. We tested the effects of chemical cleaning procedures (oxygen plasma ashing, NaClO and H2O2) and physical (ultrasounds) aimed at removing allochthonous particles. We also assessed the effects of using preservatives (formaldehyde and ethanol) and stains (Bengal Rose and Sudan Black B) prior to δ 13C and δ 18O analyses. Although the effects were generally small, three of the pre-treatments had a significant effect on δ 13C or δ 18O values. The use of Sudan Black B for vital identification caused a significant enrichment in the 13C of the samples (0.24‰). In addition, sample oxidation with hydrogen peroxide and ultrasonic cleaning each led to a slight decrease in δ 18O values (–0.18‰, in both cases). Our results demonstrate that Sudan Black B should be avoided prior to isotopic analysis. Bengal Rose showed no significant effect and should be used instead for staining. Because palaeoclimatic studies are based in small isotopic shifts, we discourage the pre-analysis use of unnecessary harsh cleaning treatments of foraminifera shell samples that may lead to isotopic fractionation and hence confound ecological interpretation. [Copyright &y& Elsevier]
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- 2008
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14. Impact of seagrass establishment, industrialization and coastal infrastructure on seagrass biogeochemical sinks.
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Serrano, Oscar, Lavery, Paul S., Bongiovanni, James, and Duarte, Carlos M.
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POSIDONIA , *SEAGRASSES , *SEAGRASS restoration , *CLIMATE change mitigation , *ECOSYSTEM dynamics , *COASTAL development , *INDUSTRIALIZATION - Abstract
The study of a Posidonia sinuosa sedimentary archive has delivered a millenary record of environmental change in Cockburn Sound (Western Australia). Ecosystem change is a major environmental problem challenging sustainable coastal development worldwide, and this study shows baseline trends and shifts in ecological processes in coastal ecosystems under environmental stress. The concentrations and fluxes of biogeochemical elements over the last 3,500 years indicate that important changes in ecosystem dynamics occurred over the last 1,000 years, in particular after ~1900's, probably related to establishment of seagrass meadows in the area and to local and regional human activities (industry and coastal development), respectively. The establishment of seagrasses ~1,000 years ago in the area of study is supported by the appearance of Posidonia fibres from ~40 cm soil depth until the core top, higher δ13C values indicating a larger contribution of seagrass-matter to the soil organic carbon pool, and increased concentration of fine sediments driven by the effect of seagrass canopy in enhancing sedimentation. The comparison of organic carbon, nutrients and metal concentrations and fluxes between pre- and post-establishment of seagrasses shows that seagrass establishment resulted in up to 9-fold increase in the soil biogeochemical sink. In ~1900's, shifts in the concentrations of metals, carbonates, organic carbon, sediment grain size, and δ13C and δ15N values of the organic matter were detected, demonstrating an alteration in seagrass ecosystem functioning following the onset of European settlement. Anthropogenic activities, and in particular the construction of a causeway in 1970's, enhanced seagrass soil organic carbon and metal accumulation rates by 36- and 39-fold, respectively, showing that human-made structures can enhance the biogeochemical sink capacity of seagrasses. Here we reconstruct the impact of human activities on seagrass ecosystem dynamics and blue carbon, which can inform local management of Cockburn Sound and seagrass conservation for climate change mitigation and adaptation. • Seagrass archives help to understand and better manage ecological change. • Seagrass establishment ~1,000 years ago increased biogeochemical sink capacity. • Ecosystem shifts followed European settlement in an Australian embayment. • Human-made structures can enhance seagrass carbon and metal sequestration. [ABSTRACT FROM AUTHOR]
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- 2020
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15. Millennial-scale changes in the molecular composition of Posidonia australis seagrass deposits: Implications for Blue Carbon sequestration.
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Kaal, Joeri, Serrano, Oscar, Martínez Cortizas, Antonio, Baldock, Jeffrey A., and Lavery, Paul S.
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SEAGRASSES , *POSIDONIA , *NUCLEAR magnetic resonance spectroscopy , *CLIMATE change mitigation , *PRINCIPAL components analysis , *CARBON cycle - Abstract
• Molecular analysis of 3200 yr Posidonia australis seagrass soil record (Australia). • Tracing diagenetic effects on sheaths and root/rhizome detritus. • Ageing-induced selective degradation of polysaccharides and enrichment of lignin. • Minor constituents cutin, suberin and tannin also preferentially depleted. • Overall C storage capacity associated with lignocellulose chemical recalcitrance. Seagrass ecosystems are recognised for their role in climate change mitigation, due to their capacity to form organic-rich sediments. The chemical recalcitrance of seagrass organs is one characteristic driving carbon storage, but the molecular background of this feature is poorly understood. We assessed molecular composition changes of Posidonia australis sheaths (SH) and roots plus rhizomes (RR) along a sediment core, encompassing 3200 cal. yr BP, by means of nuclear magnetic resonance spectroscopy (13C NMR), conventional analytical pyrolysis (Py-GC–MS) and thermally assisted hydrolysis and methylation (THM-GC–MS). Significant trends with depth (age) in the composition of both SH and RR remains of P. australis were observed from all methods. In general terms, polysaccharides become depleted (degraded) and lignin enriched (selectively preserved) as age increases, and the minor constituents cutin, suberin and condensed tannin are also preferentially depleted during ageing in both fractions. Molecular changes with ageing were smaller in SH, especially regarding polysaccharides, indicative of a superior stability compared to RR. The molecular changes observed are most pronounced within the first 75 cm of the record, which reflects the recalcitrance of P. australis detritus once it is buried below that depth (corresponding to approximately 700 cal. yr BP). The capacity of P. australis to act as a long-term carbon sink seems to be mainly related to the resistance of buried lignocellulose materials to decomposition. The results on diagenetic effects on the molecular fingerprint of seagrass detritus contribute to our understanding of carbon sequestration in Blue Carbon ecosystems. Furthermore, data comparison of the methods applied using principal component analysis (PCA) allowed us to identify consistencies, discrepancies and complementarities. [ABSTRACT FROM AUTHOR]
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- 2019
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16. The Regional Organ Procurement Collaboration Model Revisited: Influence of the Procurement Surgeon on Transplanted Abdominal Organ Outcomes.
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Serrano, Oscar K., Vock, David, Kandaswamy, Raja, Pruett, Timothy L., Matas, Arthur J., and Finger, Erik
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PROCUREMENT of organs, tissues, etc. , *ABDOMINAL abnormalities , *SURGICAL complications , *TISSUE banks , *TRANSPLANTATION of organs, tissues, etc. - Published
- 2017
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17. Clinical Utility of Postoperative Phosphate Recovery Profiles as a Predictor of Liver-Specific Morbidity after Live Donor Hepatectomy.
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Serrano, Oscar K., Mongin, Steven J., Berglund, Danielle, Goduguchinta, Varshita, Reddy, Apoorva C., Vock, David, Kirchner, Varvara A., Kandaswamy, Raja, Pruett, Timothy L., and Chinnakotla, Srinath
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HEPATECTOMY , *ORGAN donors , *HYPOPHOSPHATEMIA , *SURGICAL complications , *PHOSPHATES , *DISEASES - Published
- 2017
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18. Risk Factors for Developing Adult Cardiovascular Disease in Children Who Received a Kidney Transplant: Analysis of 1,055 Kidney Transplants between 1963-2015 at a Single Institution.
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Serrano, Oscar K., Bangdiwala, Ananta, Vock, David, Dunn, Ty B., Chinnakotla, Srinath, Finger, Erik, Kandaswamy, Raja, Pruett, Timothy L., Matas, Arthur J., and Chavers, Blanche
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CARDIOVASCULAR diseases risk factors , *KIDNEY transplantation , *JUVENILE diseases , *IMMUNOSUPPRESSION , *AZATHIOPRINE - Published
- 2016
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19. Delineating Optimal Surgical Performance in Laparoscopic Donor Nephrectomy among Transplant Surgery Fellows: A Learning Curve Analysis.
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Serrano, Oscar K., Bangdiwala, Ananta, Vock, David, Kirchner, Varvara A., Berglund, Danielle, Dunn, Ty B., Finger, Erik, Pruett, Timothy L., Matas, Arthur J., and Kandaswamy, Raja
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KIDNEY transplantation , *NEPHRECTOMY , *LAPAROSCOPIC surgery , *BLOOD loss estimation , *KIDNEY blood-vessels , *LEARNING curve - Published
- 2016
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20. Risk Factors for Developing Post-Transplant Malignancy in Children Who Receive a Kidney Transplant: Analysis of 1,055 Kidney Transplants between 1963 and 2015 at a Single Institution.
- Author
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Serrano, Oscar K., Bangdiwala, Ananta, Vock, David, Dunn, Ty B., Chinnakotla, Srinath, Finger, Erik, Kandaswamy, Raja, Pruett, Timothy L., Matas, Arthur J., and Chavers, Blanche
- Subjects
- *
KIDNEY transplantation , *CANCER risk factors , *PROPORTIONAL hazards models , *LYMPHOPROLIFERATIVE disorders , *ORGAN donors - Published
- 2016
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- View/download PDF
21. Excess weight loss is markedly reduced in Hispanics undergoing bariatric surgery: outcomes in 2,002 consecutive Hispanic patients at a single institution.
- Author
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Serrano, Oscar K., Zhang, Yang, Cumella, Lindsay, Kintzer, Emily, Ng, Nicole, Sandoval, Eduardo, Choi, Jenny J., Vemulapalli, Pratt, Melvin, W. Scott, and Camacho, Diego R.
- Subjects
- *
BARIATRIC surgery , *WEIGHT loss , *HEALTH of Hispanic Americans , *COMORBIDITY , *HEALTH outcome assessment - Published
- 2015
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- View/download PDF
22. Short- and Long-Term Outcomes for Ethnic Minorities in the United States After Liver Transplantation: Parsing the Hispanic Paradox.
- Author
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Althoff, Ashley L., Ali, Mohammad S., O'Sullivan, David M., Dar, Wasim, Emmanuel, Bishoy, Morgan, Glyn, Einstein, Michael, Richardson, Elizabeth, Sotil, Eva, Swales, Colin, Sheiner, Patricia A., and Serrano, Oscar K.
- Subjects
- *
HISPANIC Americans , *MINORITIES , *LIVER transplantation , *RACE , *GRAFT survival , *KIDNEY transplantation - Abstract
• Ethnic minorities are disproportionally affected by liver failure. • Hispanics have improved liver transplant outcomes. • African Americans have poorer survival after liver transplant. Racial and ethnic minorities are disproportionally affected by end-stage liver disease. Unfortunately, disparities in referrals to liver transplantation (LT), organ allocation, and posttransplant outcomes exist in this population. We performed a retrospective analysis of patients over the age of 18 years undergoing LT in the United States using the Scientific Registry of Transplant Recipients from 2002 to 2016. We evaluated factors associated with patient and graft outcomes and explored the effect of race and ethnicity along with social variables. During the study time period, 78,999 patients received LT. Of these, 60,102 were non-Hispanic White (NHW), 7988 were African American (AA), and 10,909 were Hispanic. AA had significantly lower patient survival, graft survival, and death-censored graft survival at both 1 and 5 years when compared to NHW. Conversely, at 1 and 5 years, patient survival and graft survival were significantly higher for Hispanics compared to NWH. In addition, AA had significantly lower survival outcomes compared to Hispanics. On multivariate analysis after controlling for race/ethnicity, age, AA race, diagnosis, and deceased donor were independent risk factors for patient death and graft failure. Despite socioeconomic disadvantages seen among Hispanics, this population appears to have improved short- and long-term survival after LT compared to NHW and AA. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
23. Role of macroalgal forests within Mediterranean shallow bays in blue carbon storage.
- Author
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Moreda, Uxue, Mazarrasa, Inés, Cebrian, Emma, Kaal, Joeri, Ricart, Aurora M., Serrano, Eduard, and Serrano, Oscar
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- 2024
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24. On the role of Posidonia oceanica beach wrack for macroinvertebrates of a Tyrrhenian sandy shore
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Colombini, Isabella, Mateo, Miguel Ángel, Serrano, Oscar, Fallaci, Mario, Gagnarli, Elena, Serrano, Laura, and Chelazzi, Lorenzo
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- *
POSIDONIA oceanica , *COLONIZATION (Ecology) , *SPECIES - Abstract
Abstract: The use of Posidonia oceanica beach wrack by macroinvertebrates of the sandy beach at Burano (Tuscany, Italy) was assessed by following the colonisation dynamics of the wrack and analysing the stable isotopes ‘scenario’ of the main local carbon and nitrogen sources and consumers. One-hundred experimental cylinders, filled with P. oceanica wrack, were placed on the beach and sampled over a 1-month period. Abundance and species richness of macroinvertebrates in wracks varied through time. Wrack was colonised by crustaceans almost immediately after deployment of the experimental cylinders. The amphipod Talitrus saltator largely dominated the faunal assembly and, together with the isopod Tylos europaeus, occupied the wracks closer to the sealine. These were followed by dipterans, staphylinids, pselaphids and tenebrionids that occurred in drier wracks higher up on the eulittoral. Moisture content of the wrack and sand decreased through space and time. This was the primary factor explaining the spatial and temporal changes observed in macroinvertebrate abundance, with species colonising or abandoning wracks according to thresholds of environmental parameters. Isotopic analysis clearly established the absence of any direct dietary link between P. oceanica wrack and macroinvertebrates. Terrestrial food sources were also discarded. Both our experimental data and a literature search showed that the organic matter from seston as filtered by the sand is the most plausible carbon and nitrogen source for beach food webs. Even if P. oceanica wrack is not a trophic source for macroinvertebrates, it is vitally important as a physical structure that provides detritivorous and predatory species with refuge from environmentally stressful conditions. [Copyright &y& Elsevier]
- Published
- 2009
- Full Text
- View/download PDF
25. Acute Myeloid Leukemia Presenting Less Than 3 Weeks After Living Donor Kidney Transplant: A Case Report.
- Author
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Yu, Jielin, Sherburne, Bradford, Chen, Yi-Bin, Kutzler, Heather L., Tremaglio, Joseph, Rochon, Caroline, Sheiner, Patricia, and Serrano, Oscar K.
- Subjects
- *
ACUTE myeloid leukemia , *KIDNEY transplantation , *HEMATOPOIETIC stem cell transplantation , *GRAFT versus host disease , *NUCLEOTIDE sequencing - Abstract
Acute myeloid leukemia (AML) is a rare malignancy with increased incidence in the kidney transplantation (KT) population for which immunosuppression has been implicated as a putative cause. The average time interval from KT to AML development is 5 years. We present the case of a 61-year-old man who was found to have peripheral blood blasts on a postoperative day 20 routine blood draw after an uneventful unrelated living donor kidney transplant. He subsequently had a bone marrow biopsy and next-generation sequencing (NGS)-based molecular testing, which demonstrated AML characterized by SMC1A and TET2 mutations. He received induction chemotherapy followed by hematopoietic cell transplantation (HCT) from the kidney donor, who happened to be matched at one haplotype. At 12 months after his HCT and 15 months after his KT, his AML remained in remission, normal renal function was preserved, no active graft-versus-host disease was present, and immunosuppression was tapering. With full donor-derived hematopoietic chimerism, we expect to be able to discontinue immunosuppression shortly, thereby achieving tolerance. The short time interval between KT and development of AML suggests the malignancy was likely present before KT. Modern NGS-based analysis offers a promising method of identifying transplant candidates with unexplained hematologic abnormalities on pre-KT testing who may benefit from formal hematologic evaluation. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
26. Donor-Recipient Matching to Optimize the Utility of High Kidney Donor Profile Index Kidneys.
- Author
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Blake-Popham, Trisha L., Vakayil, Victor, Kutzler, Heather, Rochon, Caroline L., Sheiner, Patricia A., and Serrano, Oscar K.
- Subjects
- *
KIDNEYS , *DRUG efficacy , *GLOMERULAR filtration rate , *KIDNEY transplantation , *KIDNEY physiology - Abstract
In December 2014, the Kidney Donor Profile Index (KDPI) was developed to give more precise information on donor kidney quality. Kidneys with KDPI scores ≥ 85 (K ≥ 85) have been reported to have inferior outcomes to kidneys with KDPI scores < 85. After the implementation of the new Kidney Allocation System, we developed a protocol to evaluate K ≥ 85 use. We analyzed the safety and efficacy of our institutional criteria and evaluated post-transplant outcomes. K ≥ 85 recipients were stratified based on their 1-year creatinine and estimated glomerular filtration rates to elucidate characteristics associated with serum creatinine < 1.7 mg/dL or estimated glomerular filtration rates ≤ 45 mL/min/1.73 m2. From December 2014 to December 2019, 304 deceased donor kidney transplants were performed at Hartford Hospital; 58 (19%) were K ≥ 85 with an average KDPI of 91%. There were 4 graft losses; 2 were death censored. Prolonged cold ischemia time and black recipient race were associated with inferior recipient graft function at 1 year. High KDPI kidney use requires a multifaceted evaluation that takes into account donor and recipient characteristics for an ideal match. We have identified several characteristics that may predict optimal post-transplant kidney function. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
27. Millennial-scale trends and controls in Posidonia oceanica (L. Delile) ecosystem productivity.
- Author
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Leiva-Dueñas, Carmen, Mateo, Miguel A., Martínez Cortizas, Antonio, López-Merino, Lourdes, and Serrano, Oscar
- Subjects
- *
POSIDONIA oceanica , *ECOSYSTEMS , *HOLOCENE Epoch , *ENVIRONMENTAL management , *SEAGRASSES , *PALEOCLIMATOLOGY , *SEDIMENTOLOGY - Abstract
Posidonia oceanica is a marine phanerogam that buries a significant part of its belowground production forming an organic bioconstruction known as mat. Despite Posidonia seagrass mats have proven to be reliable archives of long-term environmental change, palaeoecological studies using seagrass archives are still scarce. Here we reconstruct four millennia of environmental dynamics in the NE coast of Spain by analysing the carbon and nitrogen stable isotopic composition of P. oceanica sheaths, the proportion of different seagrass organs throughout the seagrass mat and other sedimentological proxies. The palaeoenvironmental reconstruction informs on long-term ecosystem productivity and nutrient loading, which have been linked to global (e.g., solar radiation) and local (e.g., land-use changes) factors. The long-term environmental records obtained are compared with previous palaeoecological records obtained for the area, showing a common environmental history. First, a relative seagrass ecosystem stability at ~4000 and 2000 cal. yr BP. Then, after a productivity peak at ~1400–800 cal. yr BP, productivity shows an abrupt decline to unprecedented low values. The fluctuations in ecosystem productivity are likely explained by increases in nutrient inputs related to human activities – mostly in the bay watershed – concomitantly with changes in total solar radiation. Cumulative anthropogenic stressors after Roman times may have started to affect ecosystem resilience, dynamics and productivity, with more abrupt regime shifts during the last millennium. These results add into recent research showing the potential of seagrass archives in reconstructing environmental change and seagrass post-disturbance dynamics, hence providing unvaluable information for improving the efficiency in managing these key coastal ecosystems. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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28. Potential role of seaweeds in climate change mitigation.
- Author
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Ross, Finnley W.R., Boyd, Philip W., Filbee-Dexter, Karen, Watanabe, Kenta, Ortega, Alejandra, Krause-Jensen, Dorte, Lovelock, Catherine, Sondak, Calvyn F.A., Bach, Lennart T., Duarte, Carlos M., Serrano, Oscar, Beardall, John, Tarbuck, Patrick, and Macreadie, Peter I.
- Published
- 2023
- Full Text
- View/download PDF
29. Complications after Living Donor Hepatectomy: Analysis of 176 Cases at a Single Center.
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Berglund, Danielle, Kirchner, Varvara, Pruett, Timothy, Mangalick, Saumya, Kandaswamy, Raja, Serrano, Oscar K., Benson, Bradley, Mongin, Steven, Lake, John, and Chinnakotla, Srinath
- Subjects
- *
HEPATECTOMY , *SURGICAL complications , *MEDICAL centers , *ASPARTATE aminotransferase , *QUALITY of life - Abstract
Background: Living liver donation is one of the most selfless and humane acts a person can perform. Few single-center reports have been published specifically evaluating complications and quality of life post-donation.Study Design: We conducted a retrospective analysis of outcomes of 176 living liver donors at our center to determine the incidence, type, and Clavien grade of complications, as well as long-term quality of life.Results: Of 176 living donors, 154 underwent right hepatectomy, 4 underwent left hepatectomy lobectomy, and 18 underwent left lateral segmentectomy. Mean follow-up time was 4.8 years. Complications were more frequent among right-lobe donors than left-lateral segmentectomy and left-lobe donors (p = 0.003). Of note, 82% of complications were Clavien grade 1 or 2. Of the 154 right-lobe donors, 3 had Clavien grade 3a complications, 9 had grade 3b complications (4 had bile leaks, 3 had intra-abdominal bleeding, and 2 had pleural effusions). No donor had complications that were Clavien grade 4 or higher. Per multivariate regression, resected graft volume (p = 0.0498) and post-donation international normalized ratio >2 (p = 0.00499) were significantly associated with a higher risk of Clavien grade 3 complications; however, sex, age, previous abdominal operation, post-donation bilirubin >6 mg/dL, and aspartate transaminase >650 IU/L were not. Per our 36-item Short-Form Health Survey results, donors (mean 8.3 years post-donation) reported above-average quality of life compared with standard US population. In a liver donation survey sent between 1 and 15 years post-donation, the most frequently reported problems were incisional discomfort and intolerance to fatty meals.Conclusions: In our single-center study, early complication rates were comparable with those of multicenter reports. Most complications (82%) were Clavien grade 1 or 2. During a long follow-up period, our donors continue to have improved quality of life. [ABSTRACT FROM AUTHOR]- Published
- 2018
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- View/download PDF
30. Quantifying blue carbon stocks and the role of protected areas to conserve coastal wetlands.
- Author
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Duarte de Paula Costa, Micheli, Adame, Maria Fernanda, Bryant, Catherine V., Hill, Jack, Kelleway, Jeffrey J., Lovelock, Catherine E., Ola, Anne, Rasheed, Michael A., Salinas, Cristian, Serrano, Oscar, Waltham, Nathan, York, Paul H., Young, Mary, and Macreadie, Peter
- Published
- 2023
- Full Text
- View/download PDF
31. Remote sensing for cost-effective blue carbon accounting.
- Author
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Malerba, Martino E., Duarte de Paula Costa, Micheli, Friess, Daniel A., Schuster, Lukas, Young, Mary A., Lagomasino, David, Serrano, Oscar, Hickey, Sharyn M., York, Paul H., Rasheed, Michael, Lefcheck, Jonathan S., Radford, Ben, Atwood, Trisha B., Ierodiaconou, Daniel, and Macreadie, Peter
- Subjects
- *
REMOTE sensing , *MANGROVE plants , *CLIMATE change mitigation , *SALT marshes , *MANGROVE forests , *SEAGRASSES , *CLIMATE change , *CARBON cycle - Abstract
Blue carbon ecosystems (BCE) include mangrove forests, tidal marshes, and seagrass meadows, all of which are currently under threat, putting their contribution to mitigating climate change at risk. Although certain challenges and trade-offs exist, remote sensing offers a promising avenue for transparent, replicable, and cost-effective accounting of many BCE at unprecedented temporal and spatial scales. The United Nations Framework Convention on Climate Change (UNFCCC) has issued guidelines for developing blue carbon inventories to incorporate into Nationally Determined Contributions (NDCs). Yet, there is little guidance on remote sensing techniques for monitoring, reporting, and verifying blue carbon assets. This review constructs a unified roadmap for applying remote sensing technologies to develop cost-effective carbon inventories for BCE – from local to global scales. We summarise and discuss (1) current standard guidelines for blue carbon inventories; (2) traditional and cutting-edge remote sensing technologies for mapping blue carbon habitats; (3) methods for translating habitat maps into carbon estimates; and (4) a decision tree to assist users in determining the most suitable approach depending on their areas of interest, budget, and required accuracy of blue carbon assessment. We designed this work to support UNFCCC-approved IPCC guidelines with specific recommendations on remote sensing techniques for GHG inventories. Overall, remote sensing technologies are robust and cost-effective tools for monitoring, reporting, and verifying blue carbon assets and projects. Increased appreciation of these techniques can promote a technological shift towards greater policy and industry uptake, enhancing the scalability of blue carbon as a Natural Climate Solution worldwide. • Blue carbon ecosystems (BCE) play a key role in climate change mitigation. • Remote sensing techniques are cost-effective for monitoring BCE extent and carbon stocks. • A tradeoff exists between spatial resolution and historical coverage of remotely sensed data. • New technologies can facilitate the inclusion of BCE in national inventories and Nationally Determined Contributions (NDCs). • Our decision tree guides the choice of remote sensing methods for monitoring BCE. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. Acute Care Surgery in the Cirrhotic Patient: Analysis of Clinical Outcomes Based on Triage Decisions.
- Author
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Althoff, Ashley, Croteau, Alfred, Ricaurte, Daniel, Keating, Jane, Serrano, Oscar K., PhD, Jyoti Chhabra, stephen Thompson, MSHA, and Swales, Colin
- Subjects
- *
MEDICAL triage , *SURGERY - Published
- 2021
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- View/download PDF
33. Fingerprinting macrophyte Blue Carbon by pyrolysis-GC-compound specific isotope analysis (Py-CSIA).
- Author
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Kaal, Joeri, González-Pérez, José A., Márquez San Emeterio, Layla, and Serrano, Oscar
- Published
- 2022
- Full Text
- View/download PDF
34. Impacts of land-use change and urban development on carbon sequestration in tropical seagrass meadow sediments.
- Author
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Dahl, Martin, Ismail, Rashid, Braun, Sara, Masqué, Pere, Lavery, Paul S., Gullström, Martin, Arias-Ortiz, Ariane, Asplund, Maria E., Garbaras, Andrius, Lyimo, Liberatus D., Mtolera, Matern S.P., Serrano, Oscar, Webster, Chanelle, and Björk, Mats
- Subjects
- *
SEAGRASSES , *SEAGRASS restoration , *POSIDONIA , *CARBON sequestration , *URBAN growth , *CARBON cycle , *ISOTOPIC signatures , *WASTE management - Abstract
Seagrass meadows store significant carbon stocks at a global scale, but land-use change and other anthropogenic activities can alter the natural process of organic carbon (C org) accumulation. Here, we assessed the carbon accumulation history of two seagrass meadows in Zanzibar (Tanzania) that have experienced different degrees of disturbance. The meadow at Stone Town has been highly exposed to urban development during the 20th century, while the Mbweni meadow is located in an area with relatively low impacts but historical clearing of adjacent mangroves. The results showed that the two sites had similar sedimentary C org accumulation rates (22–25 g m−2 yr−1) since the 1940s, while during the last two decades (∼1998 until 2018) they exhibited 24–30% higher accumulation of C org , which was linked to shifts in C org sources. The increase in the δ13C isotopic signature of sedimentary C org (towards a higher seagrass contribution) at the Stone Town site since 1998 points to improved seagrass meadow conditions and C org accumulation capacity of the meadow after the relocation of a major sewage outlet in the mid–1990s. In contrast, the decrease in the δ13C signatures of sedimentary C org in the Mbweni meadow since the early 2010s was likely linked to increased C org run-off of mangrove/terrestrial material following mangrove deforestation. This study exemplifies two different pathways by which land-based human activities can alter the carbon storage capacity of seagrass meadows (i.e. sewage waste management and mangrove deforestation) and showcases opportunities for management of vegetated coastal C org sinks. [Display omitted] • The seagrass carbon accumulation rate was 22–25 g C org m−2 yr−1. • The rate of carbon accumulation had increased by 24–30% during the last ∼20 years. • The increase in carbon storage was likely due to land-use change. • This study highlights the importance of land-sea connectivity for blue carbon sinks. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
35. Superior Outcomes for Hispanics after Kidney Transplantation Overshadow Access Obstacles: Understanding the Hispanic Paradox.
- Author
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Cunningham, Alyson, Ali, Mohammed, O'Sullivan, David, Kutzler, Heather, Rochon, Caroline, Morgan, Glyn, Ann Sheiner, Patricia, and Serrano, Oscar K.
- Subjects
- *
KIDNEY transplantation , *CHRONIC kidney failure , *PARADOX - Published
- 2020
- Full Text
- View/download PDF
36. Considerations in the Assessment of the Solid Organ Transplant Recipient in the COVID-19 Era: The COVID-19 Red Herring Phenomenon.
- Author
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Poulos, Constantine M., Kutzler, Heather J., Cheema, Faiqa, O'Sullivan, David, Morgan, Glyn, Rochon, Caroline, Sheiner, Patricia, and Serrano, Oscar K.
- Subjects
- *
COVID-19 , *TRANSPLANTATION of organs, tissues, etc. - Published
- 2021
- Full Text
- View/download PDF
37. Considerations in the Assessment of the Solid Organ Transplant Recipient in the COVID-19 Era: The COVID-19 Red Herring Phenomenon.
- Author
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Poulos, Constantine M., Kutzler, Heather J., Cheema, Faiqa, O'Sullivan, David, Morgan, Glyn, Rochon, Caroline, Sheiner, Patricia, and Serrano, Oscar K.
- Subjects
- *
COVID-19 , *TRANSPLANTATION of organs, tissues, etc. - Published
- 2021
- Full Text
- View/download PDF
38. Heterogeneous tidal marsh soil organic carbon accumulation among and within temperate estuaries in Australia.
- Author
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Gorham, Connor, Lavery, Paul S., Kelleway, Jeffrey J., Masque, Pere, and Serrano, Oscar
- Published
- 2021
- Full Text
- View/download PDF
39. Reconstruction of 7500 years of coastal environmental change impacting seagrass ecosystem dynamics in Oyster Harbour (SW Australia).
- Author
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Kaal, Joeri, Lavery, Paul S., Martínez Cortizas, Antonio, López-Costas, Olalla, Buchaca, Teresa, Salinas, Cristian, and Serrano, Oscar
- Subjects
- *
SEAGRASSES , *COASTAL ecosystem health , *ECOSYSTEM dynamics , *ECOLOGICAL disturbances , *COASTAL zone management , *EFFECT of human beings on climate change , *LAND clearing - Abstract
Seagrass ecosystems, which have important functions such as coastal protection and blue carbon sequestration, are threatened by anthropogenic pressure including climate change. Long-term data series from seagrass sedimentary archives (mats) can be used to understand natural cycles of environmental change and answer key questions related to contemporary management. A 7500 yr sediment record from Posidonia australis meadows in Oyster Harbour (Albany, SW Australia) was subjected to multiproxy reconstruction by means of pigment analysis (UHPLC), analytical pyrolysis (Py-GC–MS), carbonate content, δ13C and δ15N stable isotope ratios, organic C (C org) content, C org /N ratio and glomalin-related soil proteins (GRSP). The study revealed a brackish lagoon (7500–7000 cal yr BP) that was transformed in an open marine environment (7000–4100 cal yr BP) due to Holocene transgression. Earliest evidence of seagrass establishment was detected around 4500 cal yr BP, and meadow extension accelerated between 4100 and 3700 cal yr BP. The meadow environment was surprisingly resistant against environmental perturbations, as the mat, composed of P. australis seagrass fibres embedded within a siliciclastic mineral matrix containing biogenic carbonates, continued to develop steadily until 190 cal yr BP (1830 CE). Then, shifts in several proxies (pigments, GRSP) showed evidence of terrestrial runoff-triggered eutrophication/turbidity (likely driven by forest clearance and agricultural activities after European settlement), but the seagrass showed resilience (no decline of the proportion of seagrass-derived C org). By contrast, since ~1930 CE seagrass retreat is evident in the biogeochemical record: lighter δ13C values, lower lignin abundance and shifts in pigment abundance and types, affecting the balance between seagrass inputs and alternative sources, as was observed in previous studies of the area. The findings show that pigment proxies are useful early indicators of shifts in seagrass ecosystem condition, while lignocellulose and other pyrolysis products are useful proxies of more profound ecosystem alterations that influence seagrass abundance. The record indicates that the climax seagrass ecosystem condition, which prevailed for several millennia, had been impacted over the last century. Management of seagrass and coastal ecosystems should aim to avoid crossing ecological thresholds and diminish local impacts aggravating those of global change. Unlabelled Image • Seagrass ecosystems are threatened by anthropogenic pressure and climate change. • A multi-proxy record revealed long-term coastal environmental change in SW Australia. • Posidonia meadows buffered perturbations from establishment (4 ka BP) until recently. • Proxy-dependent evidence of stepwise seagrass deterioration after European colonization. • Slow building of resilience urges for prolonged protection, even after restoration. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
40. Deciphering organic matter sources and ecological shifts in blue carbon ecosystems based on molecular fingerprinting.
- Author
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Kaal, Joeri, Martínez Cortizas, Antonio, Mateo, Miguel-Ángel, and Serrano, Oscar
- Abstract
Blue carbon ecosystems (BCE) play an essential role in the global carbon cycle by removing atmospheric carbon dioxide and storing it as organic carbon (OC) in biomass and sediments. However, organic matter (OM) deposition and degradation/preservation processes are poorly understood, especially on the long-term and at molecular scales. We analysed sediment samples from six cores collected in tidal marshes, mangroves and seagrasses (up to 150 cm long cores spanning up to 10,000 yrs of OC accumulation) from Spencer Gulf (South Australia), by pyrolysis (Py-GC–MS and THM-GC–MS), and we compared the results with elemental and stable isotope data, to decipher OM provenance and to assess degradation/preservation dynamics. The results showed that: (1) the major biopolymers preserved were polysaccharides, polyphenolic moieties (lignin and tannin) and polymethylenic moieties (e.g. cutin, suberin, chlorophyll) with smaller apportions of proteins and resins; (2) the OM originates predominantly from vascular plant materials (in particular lignocellulose) that have been well-preserved, even in some of the oldest sediments; (3) mangroves were found to be the most efficient OC sinks, partially explained by syringyl lignin preservation; (4) seagrasses were shown to store polysaccharide-enriched OM; (5) large proportions of polycyclic aromatic hydrocarbons (PAHs) in surficial tidal marsh and mangrove sediments probably reflect pyrogenic OM from industrial combustion, and; (6) "ecosystem shifts", i.e. mangrove encroachment in tidal marsh and transition from seagrass to mangrove, were detected. Deposition environment and source vegetation control OC sequestration and there is no specific recalcitrant form of OM that is selectively preserved. For the first time, we demonstrate how analytical pyrolysis in combination with stable isotope analysis can be used to reconstruct (palaeo-)ecological shifts between different BCE. This study improves our knowledge on OC accumulation dynamics and the response of BCE to environmental change, which can inform the implementation of strategies for climate change mitigation. Unlabelled Image • Organic matter (OM) sources in blue carbon ecosystems studied by molecular analysis • Preservation of OM allows deciphering ecosystem shifts on a millennial timescale. • Polysaccharides, lignin and suberin moieties are major OM constituents. • Mangrove encroachment in marsh and seagrass-mangrove transition enhanced C storage. • Industrial activities and possibly palaeofires were revealed by molecular analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
41. Outcomes for Hispanics after Liver Transplantation are Comparable to Non-Hispanic Whites, Despite a Greater Burden of Disease: Parsing the Hispanic Paradox.
- Author
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Ali, Mohammed I., Cunningham, Alyson, O'Sullivan, David M., Kutzler, Heather L., Rochon, Caroline, Reginald Morgan, Glyn, Ann Sheiner, Patricia, and Serrano, Oscar K.
- Subjects
- *
LIVER transplantation , *FATTY liver - Published
- 2020
- Full Text
- View/download PDF
42. Factors regulating primary producers' assemblages in Posidonia oceanica (L.) Delile ecosystems over the past 1800 years.
- Author
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Leiva-Dueñas, Carmen, Leavitt, Peter R., Buchaca, Teresa, Cortizas, Antonio Martínez, López-Merino, Lourdes, Serrano, Oscar, Lavery, Paul S., Schouten, Stefan, and Mateo, Miguel A.
- Abstract
Posidonia oceanica (L.) Delile meadows are highly productive coastal marine ecosystems that provide multiple ecosystem services. The seagrass is not always the major contributor to total primary production, however, little is known about long-term changes in the composition of primary producers within seagrass meadows. Understanding compositional shifts within the community of primary producers is crucial to evaluate how climate and anthropogenic change affect the functioning of seagrass ecosystems. Here we analysed marker pigment composition in seagrass cores from two bays of the Cabrera Island (Balearic Islands, Spain) to asses long-term changes in phototrophic community composition and production in seagrass meadows, and identify the environmental factors triggering those changes. The proxy dataset was explored using principal component analyses (PCA): one including the pigment dataset to look for associations between producers' groups, and another one combining the pigment dataset with plausible local and global regulatory factors to assess the environmental drivers of change. Analyses of characteristic pigments and morphological fossils (cysts) showed that the abundance of dinoflagellates increased over the last 150–300 years, coeval with a rise in solar irradiance and air temperature. When compared among embayments, pigments from cyanobacteria predominated in seagrass meadows located at Es Port, a sheltered bay receiving higher terrestrial runoff; whereas pigments from diatoms, seagrasses and rodophytes were more common at Santa Maria, an exposed bay with clearer waters. Water depth also played a role in controlling the phototrophic community composition, with greater abundance of diatoms in the shallowest waters (<5 m). Overall, our results suggested that historical and spatial variation in seagrass meadows' phototrophic community composition was influenced by the interaction between local factors (catchment-bay characteristics) and global climate processes (energy influx). Together these patterns forecast how marine primary producers and seagrass ecosystem structure may respond to future global warming. Unlabelled Image • Fossil pigments can be used to reconstruct seagrass phototrophic community. • Phototrophic community composition was affected by local and global factors. • Global climate factors explained long-term changes in the dinoflagellates abundance. • Global warming may favour the development of dinoflagellates in seagrass meadows. • Phototrophic community changes might impact the seagrass ecosystem functioning. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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