303 results on '"ARORA, A. K."'
Search Results
2. Adherence of SARS‐CoV‐2 Seroepidemiologic Studies to the ROSES‐S Reporting Guideline During the COVID‐19 Pandemic.
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Cheng, Brianna, Loeschnik, Emma, Selemon, Anabel, Hosseini, Reza, Yuan, Jane, Ware, Harriet, Ma, Xiaomeng, Cao, Christian, Bergeri, Isabel, Subissi, Lorenzo, Lewis, Hannah C., Williamson, Tyler, Ronksley, Paul, Arora, Rahul K., Whelan, Mairead, and Bobrovitz, Niklas
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COVID-19 pandemic ,SARS-CoV-2 ,DATABASES ,REGRESSION analysis ,DECISION making - Abstract
Background: Complete reporting of seroepidemiologic studies is critical to their utility in evidence synthesis and public health decision making. The Reporting of Seroepidemiologic studies—SARS‐CoV‐2 (ROSES‐S) guideline is a checklist that aims to improve reporting in SARS‐CoV‐2 seroepidemiologic studies. Adherence to the ROSES‐S guideline has not yet been evaluated. Objectives: This study aims to evaluate the completeness of SARS‐CoV‐2 seroepidemiologic study reporting by the ROSES‐S guideline during the COVID‐19 pandemic, determine whether guideline publication was associated with reporting completeness, and identify study characteristics associated with reporting completeness. Methods: A random sample from the SeroTracker living systematic review database was evaluated. For each reporting item in the guideline, the percentage of studies that were adherent was calculated, as well as median and interquartile range (IQR) adherence across all items and by item domain. Beta regression analyses were used to evaluate predictors of adherence to ROSES‐S. Results: One hundred and ninety‐nine studies were analyzed. Median adherence was 48.1% (IQR 40.0%–55.2%) per study, with overall adherence ranging from 8.8% to 72.7%. The laboratory methods domain had the lowest median adherence (33.3% [IQR 25.0%–41.7%]). The discussion domain had the highest median adherence (75.0% [IQR 50.0%–100.0%]). Reporting adherence to ROSES‐S before and after guideline publication did not significantly change. Publication source (p < 0.001), study risk of bias (p = 0.001), and sampling method (p = 0.004) were significantly associated with adherence. Conclusions: Completeness of reporting in SARS‐CoV‐2 seroepidemiologic studies was suboptimal. Publication of the ROSES‐S guideline was not associated with changes in reporting practices. Authors should improve adherence to the ROSES‐S guideline with support from stakeholders. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Trends and Drivers of Terrestrial Sources and Sinks of Carbon Dioxide: An Overview of the TRENDY Project.
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Sitch, Stephen, O'Sullivan, Michael, Robertson, Eddy, Friedlingstein, Pierre, Albergel, Clément, Anthoni, Peter, Arneth, Almut, Arora, Vivek K., Bastos, Ana, Bastrikov, Vladislav, Bellouin, Nicolas, Canadell, Josep G., Chini, Louise, Ciais, Philippe, Falk, Stefanie, Harris, Ian, Hurtt, George, Ito, Akihiko, Jain, Atul K., and Jones, Matthew W.
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CARBON dioxide sinks ,ATMOSPHERIC carbon dioxide ,CARBON cycle ,CLIMATE extremes ,CLIMATE change ,PARIS Agreement (2016) ,CARBON emissions - Abstract
The terrestrial biosphere plays a major role in the global carbon cycle, and there is a recognized need for regularly updated estimates of land‐atmosphere exchange at regional and global scales. An international ensemble of Dynamic Global Vegetation Models (DGVMs), known as the "Trends and drivers of the regional scale terrestrial sources and sinks of carbon dioxide" (TRENDY) project, quantifies land biophysical exchange processes and biogeochemistry cycles in support of the annual Global Carbon Budget assessments and the REgional Carbon Cycle Assessment and Processes, phase 2 project. DGVMs use a common protocol and set of driving data sets. A set of factorial simulations allows attribution of spatio‐temporal changes in land surface processes to three primary global change drivers: changes in atmospheric CO2, climate change and variability, and Land Use and Land Cover Changes (LULCC). Here, we describe the TRENDY project, benchmark DGVM performance using remote‐sensing and other observational data, and present results for the contemporary period. Simulation results show a large global carbon sink in natural vegetation over 2012–2021, attributed to the CO2 fertilization effect (3.8 ± 0.8 PgC/yr) and climate (−0.58 ± 0.54 PgC/yr). Forests and semi‐arid ecosystems contribute approximately equally to the mean and trend in the natural land sink, and semi‐arid ecosystems continue to dominate interannual variability. The natural sink is offset by net emissions from LULCC (−1.6 ± 0.5 PgC/yr), with a net land sink of 1.7 ± 0.6 PgC/yr. Despite the largest gross fluxes being in the tropics, the largest net land‐atmosphere exchange is simulated in the extratropical regions. Plain Language Summary: Around one third of human‐induced CO2 emissions are absorbed by land ecosystems and thus act to mitigate climate change. It is essential to understand the processes, ecosystems and regions responsible for this natural carbon sink, to inform on the efficiency of the sinks into the future. These sinks are susceptible to year‐to‐year variation in response to climate variations and extremes. At the same time deforestation and other forms of land management are changing the land surface, which overall adds significantly to the human‐induced CO2 emissions. There is a need to regularly update our estimate of land carbon dynamics to aid global stock takes for the Paris agreement to avoid dangerous climate change. Here we present an international initiative that on an annual basis assesses "Trends and drivers of the regional scale terrestrial sources and sinks of carbon dioxide" (TRENDY) using computer models of the land carbon cycle. We quantify the land sink during the contemporary period (2012–2021), and attribute to processes, mainly the large opposing effects of CO2 fertilization enhancing plant productivity and land‐use change. Forests and semi‐arid ecosystems are largely responsible for the mean and trend in the land sink, with the latter most important for its year‐to‐year variation. Key Points: We quantify and attribute land carbon dynamics to underlying processes at regional scales, contributing bottom‐up estimates to RECCAP‐2Models simulate a contemporary net land sink of 1.7 ± 0.6 PgC/yr, with large opposing effects of CO2 fertilization and land‐use changeDespite the largest gross fluxes being in the tropics, the largest net land‐atmosphere exchange is simulated in the extratropical regions [ABSTRACT FROM AUTHOR]
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- 2024
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4. Salt‐tolerant plant growth‐promoting Pseudomonas atacamensis KSS‐6 in combination with organic manure enhances rice yield, improves nutrient content and soil properties under salinity stress.
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Arora, Naveen K., Mishra, Jitendra, Singh, Pradyumna, and Fatima, Tahmish
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HALOPHYTES ,MANURES ,SALINITY ,SOIL salinity ,RICE - Abstract
In the current study salt tolerant‐plant growth‐promoting rhizobacteria (ST‐PGPR) Pseudomonas atacamensis KSS‐6, selected on the basis of prominent plant growth‐promoting (PGP) and stress tolerance properties was tested as bioinoculant to improve yield of rice grown in saline soil. The ST‐PGPR KSS‐6 was capable of maintaining the PGP traits up to 200 mM NaCl, however, higher salt stress conditions affected these activities. The study was designed to determine the effect of developed talc‐based bioformulation using KSS‐6 along with organic manure (OM) on growth and yield of paddy under saline conditions. Bioformulation broadcasting was also done to examine the effect on soil properties. It was found that the combinatorial treatment showed positive impact on growth and yield of rice under saline conditions. Co‐application of KSS‐6 with OM showed maximum increment in growth, chlorophyll content, plant fresh weight, and dry weight as compared to untreated control plants. Furthermore, the combinatorial treatment improved the nutrient content (P, K, Zn, Fe, Mg, and Mn) by more than 35% and enhanced the biochemical parameters such as proline, flavonoids, carbohydrates, protein, dietary fiber, and antioxidant content of rice grains by more than 32%. Soil parameters including pH and electrical conductivity (EC), moisture content, total organic carbon, OM, sodium, and chloride ions were also improved upon treatment. There was significant lowering of EC from 7.43 to 4.3 dS/m when combination of OM and bacteria were applied. These findings suggest that the application of KSS‐6 in the form of bioinoculant could be a promising strategy to mitigate negative impacts of salt stress and enhance the yield and nutritional properties of rice grown in degraded and saline soil. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Impact of social determinants of health on time to antiretroviral therapy initiation and HIV viral undetectability for migrants enrolled in a multidisciplinary HIV clinic with rapid, free, and onsite B/F/TAF: 'The ASAP study'.
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Arora, Anish K., Vicente, Serge, Engler, Kim, Lessard, David, Huerta, Edmundo, Ishak, Joel, Routy, Jean‐Pierre, Klein, Marina, Kronfli, Nadine, Cox, Joseph, Lemire, Benoit, de Pokomandy, Alexandra, Del Balso, Lina, Sebastiani, Giada, Vedel, Isabelle, Quesnel‐Vallée, Amélie, and Lebouché, Bertrand
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COMBINATION drug therapy , *ALANINE , *HETEROCYCLIC compounds , *SOCIAL determinants of health , *VIRAL load , *BLOOD testing , *RESEARCH funding , *NOMADS , *TENOFOVIR , *PILOT projects , *HIV infections , *AMIDES , *DESCRIPTIVE statistics , *ANTIVIRAL agents , *EMTRICITABINE , *PSYCHOLOGY of HIV-positive persons , *LONGITUDINAL method , *ANTI-HIV agents , *HEALTH facilities - Abstract
Objective: Multidisciplinary care with free, rapid, and on‐site bictegravir/emtricitabine/tenofovir alafenamide (B/F/TAF) dispensation may improve health outcomes among migrants living with HIV. However, models for rapid B/F/TAF initiation are not well studied among migrants living with HIV, and an understanding of how social determinants of health (SDH) may affect HIV‐related health outcomes for migrants enrolled in such care models is limited. Methods: Within a 96‐week pilot feasibility prospective cohort study at a multidisciplinary HIV clinic, participants received free B/F/TAF rapidly after care linkage. The effects of SDH (i.e., birth region, sexual orientation, living status, education, employment, French proficiency, health coverage, use of a public health facility outside our clinic for free blood tests, and time in Canada) and other covariates (i.e., age, sex) on median time to antiretroviral therapy (ART) initiation and HIV viral undetectability from care linkage were calculated via survival analyses. Results: Thirty‐five migrants were enrolled in this study. Median time to ART initiation and HIV undetectability was 5 days (range 0–50) and 57 days (range 5–365), respectively. Those who took significantly longer to initiate ART were aged <35 years, identified as heterosexual, had less than university‐level education, or were unemployed. No factor was found to significantly affect time to undetectability. Conclusion: Despite the provision of free B/F/TAF, several SDH were linked to delays in ART initiation. However, once initiated and engaged, migrants living with HIV reached HIV undetectability efficiently. Findings provide preliminary support for adopting this care model with migrants living with HIV and suggest that SDH should be considered when designing clinical interventions for more equitable outcomes. [ABSTRACT FROM AUTHOR]
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- 2024
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6. The Impact of Climate Forcing Biases and the Nitrogen Cycle on Land Carbon Balance Projections.
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Seiler, Christian, Kou‐Giesbrecht, Sian, Arora, Vivek K., and Melton, Joe R.
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CARBON cycle ,NUTRIENT cycles ,CLIMATE change mitigation ,ATMOSPHERIC carbon dioxide ,CLIMATE change ,NITROGEN cycle ,ATMOSPHERIC nitrogen - Abstract
Earth System Models (ESMs) project that the terrestrial carbon sink will continue to grow as atmospheric CO2 increases, but this projection is uncertain due to biases in the simulated climate and how ESMs represent ecosystem processes. In particular, the strength of the CO2‐fertilization effect, which is modulated by nutrient cycles, varies substantially across models. This study evaluates land carbon balance uncertainties for the Canadian Earth System Model (CanESM) by conducting simulations where the latest version of CanESM's land surface component is driven offline with raw and bias‐adjusted CanESM5 climate forcing data. To quantify the impact of nutrient limitation, we complete simulations where the nitrogen cycle is enabled or disabled. Results show that bias adjustment improves model performance across most ecosystem variables, primarily due to reduced biases in precipitation. Turning the nitrogen cycle on increases the global land carbon sink during the historical period (1995–2014) due to enhanced nitrogen deposition, placing it within the Global Carbon Budget uncertainty range. During the future period (2080–2099), the simulated land carbon sink increases in response to bias adjustment and decreases in response to the dynamic carbon‐nitrogen interaction, leading to a net decrease when both factors are acting together. The dominating impact of the nitrogen cycle demonstrates the importance of representing nutrient limitation in ESMs. Such efforts may produce more robust carbon balance projections in support of global climate change mitigation policies such as the 2015 Paris Agreement. Plain Language Summary: The implementation of global climate change policies relies on our ability to predict how the global carbon cycle will evolve in the future. Climate models project that the biosphere will continue to absorb more CO2 than it emits, keeping atmospheric CO2 levels lower than they would be otherwise. However, the strength of this net CO2 uptake varies considerably among models. This is because of differences in the simulated climate as well as the use of different methods for simulating plant growth. This study evaluates the importance of both factors by running one model with different climate data sets and model configurations. Our results show that the future net CO2 uptake by plants increases when removing biases in climatic conditions and decreases when accounting for the impact of soil nutrients on plant growth, leading to a net decrease when both factors are acting together. The dominating impact of the nutrients demonstrates the importance of representing nutrient limitation in climate models. Such efforts may produce more robust carbon balance projections in support of global climate change mitigation policies such as the 2015 Paris Agreement. Key Points: Bias adjustment of climate forcing improves model performance across most variables, primarily due to reduced biases in precipitationThe inclusion of the N cycle increases the simulated C sink during the historical period, placing it within the observed uncertainty rangeThe future C sink increases with bias adjustment and decreases with the N cycle, resulting in a net decrease when both factors are at play [ABSTRACT FROM AUTHOR]
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- 2024
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7. Limited Mitigation Potential of Forestation Under a High Emissions Scenario: Results From Multi‐Model and Single Model Ensembles.
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Loughran, Tammas F., Ziehn, Tilo, Law, Rachel, Canadell, Josep G., Pongratz, Julia, Liddicoat, Spencer, Hajima, Tomohiro, Ito, Akihiko, Lawrence, David M., and Arora, Vivek K.
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FORESTS & forestry ,GLOBAL warming ,ATMOSPHERIC carbon dioxide ,CARBON cycle ,CARBON emissions ,FOSSIL fuels - Abstract
Forestation is a major component of future long‐term emissions reduction and CO2 removal strategies, but the viability of carbon stored in vegetation under future climates is highly uncertain. We analyze the results from seven CMIP6 models for a combined scenario with high fossil fuel emissions (from SSP5‐8.5) and forest expansion (from SSP1‐2.6) which has ∼4.8% increase in global total forest cover relative to 2015. This scenario aims to demonstrate the ability of forestation strategies to mitigate climate change under continued increasing CO2 emissions and includes the potential impacts of increased CO2 concentration and a warming climate on vegetation growth. The model intercomparison shows that forestation as a CO2 removal strategy has limited impact on global climate under a high global warming scenario, despite generating a substantial cumulative carbon sink of 10–60 Pg C over the period 2015–2100. Using a single model ensemble, we show that there are local increases in warm extremes in response to forestation associated with decreases in the number of cool days. Furthermore, we find evidence of a shift in the global carbon balance, whereby increased carbon storage on land of ∼25 Pg C by 2100 associated with forestation has a concomitant decrease in the carbon uptake by the ocean due to reduced atmospheric CO2 concentrations. Plain Language Summary: We use seven model projections to estimate future climates in which forestation occurs under a high fossil fuel emission scenario. While the forestation in this scenario is not enough to substantially mitigate global warming, the new forest cover makes up a stable carbon sink over the next century. Key Points: Forestation under a high emissions scenario is projected to generate a limited but stable carbon sinkThis sink on its own is not enough to significantly mitigate global warmingForestation has substantial impacts on the global carbon balance and regional impacts on temperature extremes [ABSTRACT FROM AUTHOR]
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- 2023
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8. A real‐world evaluation of the implementation of NLP technology in abstract screening of a systematic review.
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Perlman‐Arrow, Sara, Loo, Noel, Bobrovitz, Niklas, Yan, Tingting, and Arora, Rahul K.
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NATURAL language processing ,SCREEN time ,SATISFACTION - Abstract
The laborious and time‐consuming nature of systematic review production hinders the dissemination of up‐to‐date evidence synthesis. Well‐performing natural language processing (NLP) tools for systematic reviews have been developed, showing promise to improve efficiency. However, the feasibility and value of these technologies have not been comprehensively demonstrated in a real‐world review. We developed an NLP‐assisted abstract screening tool that provides text inclusion recommendations, keyword highlights, and visual context cues. We evaluated this tool in a living systematic review on SARS‐CoV‐2 seroprevalence, conducting a quality improvement assessment of screening with and without the tool. We evaluated changes to abstract screening speed, screening accuracy, characteristics of included texts, and user satisfaction. The tool improved efficiency, reducing screening time per abstract by 45.9% and decreasing inter‐reviewer conflict rates. The tool conserved precision of article inclusion (positive predictive value; 0.92 with tool vs. 0.88 without) and recall (sensitivity; 0.90 vs. 0.81). The summary statistics of included studies were similar with and without the tool. Users were satisfied with the tool (mean satisfaction score of 4.2/5). We evaluated an abstract screening process where one human reviewer was replaced with the tool's votes, finding that this maintained recall (0.92 one‐person, one‐tool vs. 0.90 two tool‐assisted humans) and precision (0.91 vs. 0.92) while reducing screening time by 70%. Implementing an NLP tool in this living systematic review improved efficiency, maintained accuracy, and was well‐received by researchers, demonstrating the real‐world effectiveness of NLP in expediting evidence synthesis. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Tau as a diagnostic instrument in clinical trials to predict amyloid in Alzheimer's disease.
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Shcherbinin, Sergey, Morris, Amanda, Higgins, Ixavier A., Tunali, Ilke, Lu, Ming, Deveau, Carmen, Southekal, Sudeepti, Kotari, Vikas, Evans, Cynthia D., Arora, Anupa K., Collins, Emily C., Pontecorvo, Michael, Mintun, Mark A., and Sims, John R.
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ALZHEIMER'S disease ,CEREBRAL amyloid angiopathy ,CHRONIC traumatic encephalopathy ,TAU proteins ,AMYLOID ,POSITRON emission tomography ,CLINICAL trials - Abstract
INTRODUCTION: Alzheimer's disease (AD) is characterized by the presence of both amyloid and tau pathology. In vivo diagnosis can be made with amyloid and tau positron emission tomography (PET) imaging. Emergent evidence supports that amyloid and tau accumulation are associated and that amyloid accumulation may precede that of tau. This report further investigates the relationship between amyloid and tau to assess whether elevated cortical tau can predict elevated amyloid in participants with early symptomatic AD. METHODS: Florbetapir F18 and flortaucipir F18 uptake were evaluated from baseline PET scans collected in three multi‐center studies with cognitively impaired participants, including A05 (N = 306; NCT02016560), TB (N = 310; TRAILBLAZER‐ALZ; NCT03367403), and TB2 (N = 1165; TRAILBLAZER‐ALZ 2; NCT04437511). Images were assessed using visual and quantitative approaches to establish amyloid (A+) and tau (T+) positivity, as well as a combination method (tauVQ) to establish T+. Associations between global amyloid and tau were evaluated with positive and negative predictive values (PPV, NPV) and likelihood ratios (LR+, LR–). Predictive values within subgroups according to ethnicity, race, cognitive score, age, and sex were also evaluated. The relationship between regional tau (four target and two reference regions were tested) and global amyloid was investigated in A05 participant scans using receiver‐operating characteristic (ROC) curves. RESULTS: PPV for amyloid positivity was ≥93% for all three trials using various A+ and T+ definitions, including visual, quantitative, and combination methods. Population characteristics did not have an impact on A+ predictability. Regional analyses (early tau (Eτ) volume of interest (VOI), temporal, parietal, frontal) revealed significant area under the ROC curve in Eτ VOI compared to frontal region, regardless of reference region and consistent among visual and quantitative A+ definitions (p < 0.001). DISCUSSION: These findings suggest that a positive tau PET scan is associated (≥93%) with amyloid positivity in individuals with early symptomatic AD, with the potential benefits of reducing clinical trial and health care expenses, radiation exposure, and participant time. Highlights: Positron emission tomography (PET) evaluates candidates for Alzheimer's disease (AD) research. A positive tau PET scan is associated (≥93%) with amyloid positivity.A positive amyloid PET is not necessarily associated with tau positivity.Tau PET could be the sole diagnostic tool to confirm candidates for AD trials. [ABSTRACT FROM AUTHOR]
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- 2023
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10. SeroTracker‐RoB: A decision rule‐based algorithm for reproducible risk of bias assessment of seroprevalence studies.
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Bobrovitz, Niklas, Noël, Kim, Li, Zihan, Cao, Christian, Deveaux, Gabriel, Selemon, Anabel, Clifton, David A., Yanes‐Lane, Mercedes, Yan, Tingting, and Arora, Rahul K.
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SEROPREVALENCE ,RISK assessment ,ALGORITHMS ,INTRACLASS correlation ,DISEASE outbreaks - Abstract
Risk of bias (RoB) assessments are a core element of evidence synthesis but can be time consuming and subjective. We aimed to develop a decision rule‐based algorithm for RoB assessment of seroprevalence studies. We developed the SeroTracker‐RoB algorithm. The algorithm derives seven objective and two subjective critical appraisal items from the Joanna Briggs Institute Critical Appraisal Checklist for Prevalence studies and implements decision rules that determine study risk of bias based on the items. Decision rules were validated using the SeroTracker seroprevalence study database, which included non‐algorithmic RoB judgments from two reviewers. We quantified efficiency as the mean difference in time for the algorithmic and non‐algorithmic assessments of 80 randomly selected articles, coverage as the proportion of studies where the decision rules yielded an assessment, and reliability using intraclass correlations comparing algorithmic and non‐algorithmic assessments for 2070 articles. A set of decision rules with 61 branches was developed using responses to the nine critical appraisal items. The algorithmic approach was faster than non‐algorithmic assessment (mean reduction 2.32 min [SD 1.09] per article), classified 100% (n = 2070) of studies, and had good reliability compared to non‐algorithmic assessment (ICC 0.77, 95% CI 0.74–0.80). We built the SeroTracker‐RoB Excel Tool, which embeds this algorithm for use by other researchers. The SeroTracker‐RoB decision‐rule based algorithm was faster than non‐algorithmic assessment with complete coverage and good reliability. This algorithm enabled rapid, transparent, and reproducible RoB evaluations of seroprevalence studies and may support evidence synthesis efforts during future disease outbreaks. This decision rule‐based approach could be applied to other types of prevalence studies. [ABSTRACT FROM AUTHOR]
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- 2023
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11. High frequency of memory stem cells with a distinct gene signature in HIV patients with treatment interruption.
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Sachdeva, Meenakshi, Sharma, Aman, and Arora, Sunil K.
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STEM cells ,HIV-positive persons ,ANTIRETROVIRAL agents ,GENE expression ,RNA sequencing ,PATIENT compliance - Abstract
Reservoirs of HIV remain a major obstacle to the complete eradication of virus despite regular anti‐retroviral therapy (ART). Memory stem cells (Tscm), one of the major reservoirs, are relatively less studied owing to their presence in lower numbers and inaccessible anatomical locations. We have evaluated the molecular characteristics of Tscms in patients with ART interruption (n = 15) versus patients on uninterrupted ART (n = 12) using flow cytometry. RNA sequencing was done in the sorted Tscms to study the differential gene expression. Patients with ART interruption had significantly lower baseline CD4+T‐cell counts and high viral loads as compared to patients on ART. The former group had significantly higher frequency of CD4+ and CD8+Tscms with a higher expression of PD‐1 on CD8+Tscms. The transcriptome profile of Tscm was significantly different among the patient groups. The main pathways were cellular and metabolic pathways, cellular development pathways, cell differentiation and negative regulation of cellular migratory pathways. An increased yet dysfunctional CD8+ memory stem cells describe HIV‐1‐infected patients with break‐in ART and a distinct transcriptional signature of CD4+ Tscm as compared to those of patients on ART. A more detailed understanding of the biology and dynamics of Tscm in future studies is warranted. Strategies to improve the functionality of the CD8+ Tscm will help these patients to tackle the outburst of viral replication that occurs after the cessation of therapy. [ABSTRACT FROM AUTHOR]
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- 2023
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12. Compensatory Effects Between CO2, Nitrogen Deposition, and Nitrogen Fertilization in Terrestrial Biosphere Models Without Nitrogen Compromise Projections of the Future Terrestrial Carbon Sink.
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Kou‐Giesbrecht, S. and Arora, V. K.
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CARBON cycle , *BIOSPHERE , *ATMOSPHERIC nitrogen , *NITROGEN cycle , *GOVERNMENT policy on climate change , *NITROGEN , *AGRICULTURAL intensification , *CARBON sequestration - Abstract
Although terrestrial biosphere models (TBMs) with and without nitrogen cycling successfully reproduce the historical terrestrial carbon sink, the influence of nitrogen cycling under interacting and intensifying global change drivers in the future is unclear. Here, we compare TBM projections with and without nitrogen cycling over alternative future scenarios (the Shared Socioeconomic Pathways) to examine how representing nitrogen cycling influences CO2 fertilization as well as the effects of a comprehensive group of physical and socioeconomic global change drivers. Because elevated nitrogen deposition and nitrogen fertilization have stimulated terrestrial carbon sequestration over the historical period, a model without nitrogen cycling must exaggerate the strength of CO2 fertilization to compensate for these unrepresented nitrogen processes and to reproduce the historical terrestrial carbon sink. As a result, it cannot realistically project the future terrestrial carbon sink, overestimating CO2 fertilization as the trajectories of CO2, nitrogen deposition and nitrogen fertilization diverge in future scenarios. Plain Language Summary: Terrestrial biosphere models simulate the terrestrial carbon sink (in plant and soil biomass), which takes up a third of anthropogenic CO2 emissions. However, the influence of nitrogen cycling and nitrogen limitation of plant growth in the Shared Socioeconomic Pathways (SSPs) (recently adopted alternative scenarios for the 21st century) is unclear. Here, we compare a model with and without nitrogen cycling in comprehensive simulations of the SSPs. We find that a model without nitrogen must exaggerate the influence of elevated CO2 on plant growth to compensate for unrepresented nitrogen cycling processes in order to correctly simulate the historical terrestrial carbon sink. Specifically, it does not represent how elevated atmospheric nitrogen input (due to intensive agriculture and fossil fuel burning) and elevated nitrogen fertilization have increased plant growth over the historical period. As a result, models without nitrogen cannot realistically project the future terrestrial carbon sink because they are calibrated to reproduce the historical terrestrial carbon sink but the trajectories of CO2, atmospheric nitrogen input, and nitrogen fertilization diverge from their historical trajectories in future scenarios. This leads to an overestimation of the future terrestrial carbon sink by models without nitrogen with implications for climate change projections and policy. Key Points: Terrestrial biosphere models without N do not represent N deposition or N fertilization, which have stimulated terrestrial C sequestrationExaggerated CO2 fertilization compensates for N deposition and N fertilization in order to reproduce the historical terrestrial C sinkModels without N cannot project the future terrestrial C sink as trajectories of CO2, N deposition, and N fertilization diverge [ABSTRACT FROM AUTHOR]
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- 2023
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13. Lessons from the pandemic: Responding to emerging zoonotic viral diseases—a Keystone Symposia report.
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Cable, Jennifer, Fauci, Anthony, Dowling, William E., Günther, Stephan, Bente, Dennis A., Yadav, Pragya Dhruv, Madoff, Lawrence C., Wang, Lin‐Fa, Arora, Rahul K., Van Kerkhove, Maria, Chu, May C., Jaenisch, Thomas, Epstein, Jonathan H., Frost, Simon David William, Bausch, Daniel G., Hensley, Lisa E., Bergeron, Éric, Sitaras, Ioannis, Gunn, Michael D., and Geisbert, Thomas W.
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VIRUS diseases ,ZOONOSES ,PANDEMICS ,COVID-19 pandemic ,NIPAH virus ,PLANT viruses - Abstract
The COVID‐19 pandemic caught the world largely unprepared, including scientific and policy communities. On April 10–13, 2022, researchers across academia, industry, government, and nonprofit organizations met at the Keystone symposium "Lessons from the Pandemic: Responding to Emerging Zoonotic Viral Diseases" to discuss the successes and challenges of the COVID‐19 pandemic and what lessons can be applied moving forward. Speakers focused on experiences not only from the COVID‐19 pandemic but also from outbreaks of other pathogens, including the Ebola virus, Lassa virus, and Nipah virus. A general consensus was that investments made during the COVID‐19 pandemic in infrastructure, collaborations, laboratory and manufacturing capacity, diagnostics, clinical trial networks, and regulatory enhancements—notably, in low‐to‐middle income countries—must be maintained and strengthened to enable quick, concerted responses to future threats, especially to zoonotic pathogens. [ABSTRACT FROM AUTHOR]
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- 2022
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14. Enhanced India‐Africa Carbon Uptake and Asia‐Pacific Carbon Release Associated With the 2019 Extreme Positive Indian Ocean Dipole.
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Wang, Jun, Jiang, Fei, Ju, Weimin, Wang, Meirong, Sitch, Stephen, Arora, Vivek K., Chen, Jing M., Goll, Daniel S., He, Wei, Jain, Atul K., Li, Xing, Joiner, Joanna, Poulter, Benjamin, Séférian, Roland, Wang, Hengmao, Wu, Mousong, Xiao, Jingfeng, Yuan, Wenping, Yue, Xu, and Zaehle, Sönke
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CARBON cycle ,CLIMATE extremes ,OCEAN ,DROUGHT management ,SOIL moisture ,CARBON ,HEAT waves (Meteorology) - Abstract
The 2019 extreme positive Indian Ocean dipole drove climate extremes over Indian Ocean rim countries with unclear carbon‐cycle responses. We investigated its impact on net biome productivity (NBP) and its constituent fluxes, using the Global Carbon Assimilation System (GCASv2) product, process‐based model simulations from TRENDYv9, and satellite‐based gross primary productivity (GPP). By distinguishing two separate regions, the India‐Africa and Asia‐Pacific, GCASv2 indicated enhanced terrestrial carbon uptake of 0.23 ± 0.20 PgC and release of 0.38 ± 0.15 PgC, respectively, during September–December (SOND) 2019. These NBP anomalies had comparable magnitudes to those following the 2015 extreme El Niño which, however, caused the consistent carbon release in both regions. The TRENDYv9 model ensemble confirmed these NBP responses, albeit with smaller magnitudes. These regional NBP anomalies were related to soil moisture variations with a dominant role of GPP. Understanding the impact of IOD provides new insights into mechanisms driving interannual variations in regional carbon cycling. Plain Language Summary: The extreme Indian Ocean Dipole (IOD) can drive climate extremes, such as floods, heatwaves, droughts, and wildfires, over the Indian Ocean rim countries. However, responses of regional terrestrial carbon cycling to IOD remained unclear. We used the net biome productivity (NBP) from an atmospheric inversion and multiple terrestrial biosphere models to demonstrate an enhanced terrestrial carbon uptake and release over the India‐Africa and Asia‐Pacific regions, respectively, during the extreme positive IOD (September–December) in 2019. These IOD‐induced regional NBP anomalies showed comparable magnitudes but different patterns to those following the 2015 extreme El Niño. Along with the more frequent extreme IOD under future greenhouse warming, IOD will be an important mechanism driving interannual variations in regional carbon cycling. Key Points: The 2019 extreme positive Indian Ocean Dipole caused the enhanced land carbon uptake over India‐Africa and release over Asia‐Pacific during September–DecemberThese regional net biome productivity (NBP) anomalies were closely related to soil moisture variations with a dominant role of gross primary productivityThese Indian Ocean Dipole‐induced regional NBP anomalies showed comparable magnitudes but different patterns to those following the 2015 extreme El Niño [ABSTRACT FROM AUTHOR]
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- 2022
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15. Representing the Dynamic Response of Vegetation to Nitrogen Limitation via Biological Nitrogen Fixation in the CLASSIC Land Model.
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Kou‐Giesbrecht, Sian and Arora, Vivek K.
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NITROGEN cycle ,NITROGEN fixation ,CARBON cycle ,BIOGEOCHEMICAL cycles ,NITROGEN ,CARBON sequestration - Abstract
Despite its pivotal feedback to carbon cycling, representing the dynamic response of vegetation to nitrogen limitation is a key challenge for simulating the terrestrial carbon sink with land models. Here, we explore a representation of this dynamic response of vegetation to nitrogen limitation with a novel representation of biological nitrogen fixation and nitrogen cycling in the Canadian Land Surface Scheme Including Biogeochemical Cycles. First, we assess how incorporating the dynamic response of vegetation to nitrogen limitation via biological nitrogen fixation influences the response to CO2 and nitrogen fertilization experiments, comparing simulations against observation‐based estimates from meta‐analyses. This evaluates whether the underlying mechanisms are realistically represented. Second, we assess how incorporating the dynamic response of vegetation to nitrogen limitation via biological nitrogen fixation affects simulated terrestrial carbon sequestration over the 20th and early 21st century, examining the effects of global change drivers (CO2, nitrogen deposition, climate, and land‐use change) acting both individually and concurrently. Including nitrogen cycling reduces the terrestrial carbon sink driven by elevated CO2 over the historical period. Representing the dynamic response of vegetation to nitrogen limitation via biological nitrogen fixation increases the estimate of the present‐day terrestrial carbon sink by 0.2 Pg C yr−1 (because elevated CO2 intensifies nitrogen limitation, which drives the upregulation of biological nitrogen fixation, alleviating nitrogen limitation). Our results highlight the importance of the dynamic response of vegetation to nitrogen limitation for realistically projecting the future terrestrial carbon sink under global change with land models. Key Points: The dynamic response of vegetation to nitrogen limitation is critical for simulating the terrestrial carbon sink with land modelsIt determines the response of terrestrial carbon and nitrogen cycling to CO2, nitrogen deposition, and other global change driversElevated CO2 intensifies nitrogen limitation, which drives the upregulation of biological nitrogen fixation, alleviating nitrogen limitation [ABSTRACT FROM AUTHOR]
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- 2022
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16. Are Terrestrial Biosphere Models Fit for Simulating the Global Land Carbon Sink?
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Seiler, Christian, Melton, Joe R., Arora, Vivek K., Sitch, Stephen, Friedlingstein, Pierre, Anthoni, Peter, Goll, Daniel, Jain, Atul K., Joetzjer, Emilie, Lienert, Sebastian, Lombardozzi, Danica, Luyssaert, Sebastiaan, Nabel, Julia E. M. S., Tian, Hanqin, Vuichard, Nicolas, Walker, Anthony P., Yuan, Wenping, and Zaehle, Sönke
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BIOSPHERE ,CARBON cycle ,LEAF area index ,CARBON emissions ,REMOTE-sensing images - Abstract
The Global Carbon Project estimates that the terrestrial biosphere has absorbed about one‐third of anthropogenic CO2 emissions during the 1959–2019 period. This sink‐estimate is produced by an ensemble of terrestrial biosphere models and is consistent with the land uptake inferred from the residual of emissions and ocean uptake. The purpose of our study is to understand how well terrestrial biosphere models reproduce the processes that drive the terrestrial carbon sink. One challenge is to decide what level of agreement between model output and observation‐based reference data is adequate considering that reference data are prone to uncertainties. To define such a level of agreement, we compute benchmark scores that quantify the similarity between independently derived reference data sets using multiple statistical metrics. Models are considered to perform well if their model scores reach benchmark scores. Our results show that reference data can differ considerably, causing benchmark scores to be low. Model scores are often of similar magnitude as benchmark scores, implying that model performance is reasonable given how different reference data are. While model performance is encouraging, ample potential for improvements remains, including a reduction in a positive leaf area index bias, improved representations of processes that govern soil organic carbon in high latitudes, and an assessment of causes that drive the inter‐model spread of gross primary productivity in boreal regions and humid tropics. The success of future model development will increasingly depend on our capacity to reduce and account for observational uncertainties. Plain Language Summary: Earth's natural vegetation absorbs about one‐third of CO2 emissions caused by human activities. This value is produced by a group of models rather than through direct observations. Our study assesses how well models reproduce the processes that drive the CO2 exchange between land and atmosphere using a wide range of data sets that are mainly derived from field measurements and satellite images. These reference data sets are prone to errors that are not quantified in a consistent manner. To account for such errors, we first compare different reference data sets against each other. We then compare model output against reference data and assess whether the differences are comparable to the differences among the reference data sets. We conclude that the performance of models is encouraging given how uncertain reference data are, but that ample potential for improvements remains. Key Points: Differences between model and observations are often similar compared to differences between independently derived observation‐based dataWe quantify differences between independently derived observations to disentangle model deficiencies from observational uncertaintiesFuture work should address biases in soil organic carbon, leaf area index, and the large spread of gross primary productivity among models [ABSTRACT FROM AUTHOR]
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- 2022
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17. Expanding role of PI5P4Ks in cancer: A promising druggable target.
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Arora, Gurpreet K., Palamiuc, Lavinia, and Emerling, Brooke M.
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DRUG target , *KINASES - Abstract
Cancer cells are challenged by a myriad of microenvironmental stresses, and it is their ability to efficiently adapt to the constantly changing nutrient, energy, oxidative, and/or immune landscape that allows them to survive and proliferate. Such adaptations, however, result in distinct vulnerabilities that are attractive therapeutic targets. Phosphatidylinositol 5‐phosphate 4‐kinases (PI5P4Ks) are a family of druggable stress‐regulated phosphoinositide kinases that become conditionally essential as a metabolic adaptation, paving the way to targeting cancer cell dependencies. Further, PI5P4Ks have a synthetic lethal interaction with the tumor suppressor p53, the loss of which is one of the most prevalent genetic drivers of malignant transformation. PI5P4K's emergence as a crucial axis in the expanding landscape of phosphoinositide signaling in cancer has already stimulated the development of specific inhibitors. Thus, a better understanding of the biology of the PI5P4Ks will allow for targeted and effective therapeutic interventions. Here, we attempt to summarize the mounting roles of the PI5P4Ks in cancer, including evidence that targeting them is a therapeutic vulnerability and promising next‐in‐line treatment for multiple cancer subtypes. [ABSTRACT FROM AUTHOR]
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- 2022
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18. Measurement invariance of the Childhood Autism Rating Scale (CARS) across six countries.
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Stevanovic, Dejan, Costanzo, Floriana, Fucà, Elisa, Valeri, Giovanni, Vicari, Stefano, Robins, Diana L., Samms‐Vaughan, Maureen, Ozek Erkuran, Handan, Yaylaci, Ferhat, Deshpande, Smita N., Deshmukh, Vaishali, Arora, Narendra K., Albores‐Gallo, Lilia, García‐López, Cristina, Gatica‐Bahamonde, Gabriel, Gabunia, Maia, Zirakashvili, Medea, Machado, Fernanda Prada, Radan, Miruna, and Samadi, Sayyed Ali
- Abstract
The Childhood Autism Rating Scale (CARS) is a simple and inexpensive tool for Autism spectrum disorder (ASD) assessments, with evidenced psychometric data from different countries. However, it is still unclear whether ASD symptoms are measured the same way across different societies and world regions with this tool, since data on its cross‐cultural validity are lacking. This study evaluated the cross‐cultural measurement invariance of the CARS among children with ASD from six countries, for whom data were aggregated from previous studies in India (n = 101), Jamaica (n = 139), Mexico (n = 72), Spain (n = 99), Turkey (n = 150), and the United States of America (n = 186). We analyzed the approximate measurement invariance based on Bayesian structural equation modeling. The model did not fit the data and its measurement invariance did not hold, with all items found non‐invariant across the countries. Items related to social communication and interaction (i.e., relating to people, imitation, emotional response, and verbal and nonverbal communication) displayed lower levels of cross‐country non‐invariance compared to items about stereotyped behaviors/sensory sensitivity (i.e., body and object use, adaptation to change, or taste, smell, and touch response). This study found that the CARS may not provide cross‐culturally valid ASD assessments. Thus, cross‐cultural comparisons with the CARS should consider first which items operate differently across samples of interest, since its cross‐cultural measurement non‐invariance could be a source of cross‐cultural variability in ASD presentations. Additional studies are needed before drawing valid recommendations in relation to the cultural sensitivity of particular items. Lay Summary: The Childhood Autism Rating Scale (CARS) is a widely used and inexpensive tool for autism assessments across the globe. We tested its cross‐cultural validity among children with autism from India, Jamaica, Mexico, Spain, Turkey, and the United States of America. All CARS items operated differently across these countries, which indicates that they may not provide cross‐culturally valid assessments. Comparing CARS data across regional and linguistically diverse samples requires first determining which items operate differently across the samples. [ABSTRACT FROM AUTHOR]
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- 2021
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19. Pattern and burden of opioid‐related hospitalizations in the USA from 2016 to 2018.
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Bedi, Prabhjot, Rai, Manoj P., Bumrah, Karandeep, Singh, Vikas K., Arora, Tanureet K., and Singh, Tanveer
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OPIOID epidemic ,REGRESSION analysis ,HOSPITAL care ,ZIP codes ,DIAGNOSIS ,OPIOID analgesics - Abstract
Aims: The current opioid crisis in the USA is a formidable challenge for the healthcare system, and the general population. Our objective is to characterize the burden of opioid‐related disorders in an inpatient setting in the USA for the years 2016, 2017 and 2018 using the National Inpatient Sample (NIS). Methods: A cross‐sectional analysis of the NIS was performed to identify and analyse hospitalizations with an opioid‐related diagnosis in 2016, 2017 and 2018. Descriptive statistics and regression models were utilized to define the demographics of the population of interest and measure the outcomes. Results: We identified 962 900 discharges with opioid‐related diagnosis in 2016, 982 710 in 2017 and 942 110 in 2018. The majority were age <60 years, were found in residents of low‐income zip codes and covered by Medicaid. The adjusted mean total hospitalization cost trended up from $12 828 (95% confidence interval [CI] 12 547–13 108) in 2016, to $13164.9 (95% CI 12 872.47–13 457.34) in 2017 and then to $13 626.65 (95% CI 13 325.95–13 927.34) in 2018. The adjusted mortality was highest in 2016; 2.26% (95% CI 2.16–2.35) and it trended down to 1.97% (95% CI 1.88–2.05) in 2017, and to 1.89% (95% CI 1.81–1.98) in 2018. Conclusions: Opioid‐related disorders cause a significant number of hospitalizations in the USA. A large proportion of these patients are age <60 years, have lower household income, and are covered by Medicaid. Programmes directed towards this specific group can help reduce the overall burden of hospitalizations. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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20. Galectin‐3 and CD117 immunocytochemistry in the diagnosis of indeterminate thyroid lesions: A pilot study.
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Dixit, Sonali, Diwaker, Preeti, Wadhwa, Neelam, and Arora, Vinod K.
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- 2021
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21. The next three epochs: Health system challenges amidst and beyond the COVID‐19 era.
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Arora, Anish K.
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- 2021
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22. Climate‐Driven Variability and Trends in Plant Productivity Over Recent Decades Based on Three Global Products.
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O'Sullivan, Michael, Smith, William K., Sitch, Stephen, Friedlingstein, Pierre, Arora, Vivek K., Haverd, Vanessa, Jain, Atul K., Kato, Etsushi, Kautz, Markus, Lombardozzi, Danica, Nabel, Julia E. M. S., Tian, Hanqin, Vuichard, Nicolas, Wiltshire, Andy, Zhu, Dan, and Buermann, Wolfgang
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PLANT productivity ,TROPICAL forests ,CARBON cycle ,HOTEL suites ,UNCERTAINTY ,WATER supply - Abstract
Variability in climate exerts a strong influence on vegetation productivity (gross primary productivity; GPP), and therefore has a large impact on the land carbon sink. However, no direct observations of global GPP exist, and estimates rely on models that are constrained by observations at various spatial and temporal scales. Here, we assess the consistency in GPP from global products which extend for more than three decades; two observation‐based approaches, the upscaling of FLUXNET site observations (FLUXCOM) and a remote sensing derived light use efficiency model (RS‐LUE), and from a suite of terrestrial biosphere models (TRENDYv6). At local scales, we find high correlations in annual GPP among the products, with exceptions in tropical and high northern latitudes. On longer time scales, the products agree on the direction of trends over 58% of the land, with large increases across northern latitudes driven by warming trends. Further, tropical regions exhibit the largest interannual variability in GPP, with both rainforests and savannas contributing substantially. Variability in savanna GPP is likely predominantly driven by water availability, although temperature could play a role via soil moisture‐atmosphere feedbacks. There is, however, no consensus on the magnitude and driver of variability of tropical forests, which suggest uncertainties in process representations and underlying observations remain. These results emphasize the need for more direct long‐term observations of GPP along with an extension of in situ networks in underrepresented regions (e.g., tropical forests). Such capabilities would support efforts to better validate relevant processes in models, to more accurately estimate GPP. Key Points: Changes in climate over the period 1982–2016 have increased GPP at a global scale and across northern latitudesSavannas and tropical forests are hotspots for IAV in GPP, although the dominant climate drivers are not consistent among the assessed productsDGVMs systematically underestimate the IAV of GPP in tropical forests, highlighting the need for improved parameterizations/formulations [ABSTRACT FROM AUTHOR]
- Published
- 2020
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23. Neutrophil dysfunction predicts 90‐day survival in patients with acute on chronic liver failure: A longitudinal case–control study.
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Makkar, Kunaal, Tomer, Shallu, Verma, Nipun, Rathi, Sahaj, Arora, Sunil K, Taneja, Sunil, Duseja, Ajay, Chawla, Yogesh K, and Dhiman, Radha K
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LIVER failure ,LIVER diseases ,NEUTROPHILS ,CIRRHOSIS of the liver ,PHENOTYPES - Abstract
Background and Aim: Innate immune disarray is a key component in the development and progression of acute on chronic liver failure (ACLF) and predisposition to infections. We evaluated the neutrophil dysfunction and its impact on outcomes in patients with ACLF. Methods: Forty patients with acute decompensation of cirrhosis (10 each of grades 0, 1, 2, and 3 ACLF) and 10 healthy controls were prospectively evaluated for neutrophil immunophenotype (NP), neutrophil phagocytic capacity (NPC), and oxidative burst (OB) in both resting and stimulated conditions. The patients were followed up for 90 days or until death or transplant, whichever was earlier. Results: NP was normal (in %) and NPC (in mean fluorescence intensity [MFI]) was better in controls compared to patients with ACLF (83.74 ± 12.38 vs 63.84 ± 22.98; P = 0.007 and 98.33 ± 130.60 vs 18.73 ± 17.88, P = 0.001, respectively). Resting OB was higher in patients with ACLF compared to controls (97 ± 4.9% vs 91 ± 9%; P = 0.034), but it failed to increase further after stimulation, suggesting an immune exhaustion. NP was normal (in %) and NPC (in MFI) was better in 90‐day survivors compared to nonsurvivors (78 ± 11.9 vs 62.2 ± 24.11, P = 0.02 and 33.3 ± 22.7 vs 16.36 ± 13.3; P = 0.004, respectively). Phenotypically normal neutrophils >71.7% had 78.6% sensitivity and 65.4% specificity with an area under receiver operating curve (AUROC) of 0.70 (95% confidence interval [CI]: 0.55–0.90); P = 0.017, and NPC >17.32. MFI had 71.4% sensitivity and 69.6% specificity with an AUROC of 0.73 (95% CI: 0.54–0.86), P = 0.035, in predicting 90‐day survival. Conclusion: Neutrophils have impaired bactericidal function in patients with ACLF compared to healthy adults. Neutrophil phenotype and phagocytic capacity may be used to predict 90‐day survival in patients with ACLF. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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24. Causes of slowing‐down seasonal CO2 amplitude at Mauna Loa.
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Wang, Kai, Wang, Yilong, Wang, Xuhui, He, Yue, Li, Xiangyi, Keeling, Ralph F., Ciais, Philippe, Heimann, Martin, Peng, Shushi, Chevallier, Frédéric, Friedlingstein, Pierre, Sitch, Stephen, Buermann, Wolfgang, Arora, Vivek K., Haverd, Vanessa, Jain, Atul K., Kato, Etsushi, Lienert, Sebastian, Lombardozzi, Danica, and Nabel, Julia E. M. S.
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ATMOSPHERIC circulation ,ATMOSPHERIC transport ,CARBON cycle ,CLIMATE change ,AGRICULTURAL intensification ,LAND-atmosphere interactions - Abstract
Changing amplitude of the seasonal cycle of atmospheric CO2 (SCA) in the northern hemisphere is an emerging carbon cycle property. Mauna Loa (MLO) station (20°N, 156°W), which has the longest continuous northern hemisphere CO2 record, shows an increasing SCA before the 1980s (p <.01), followed by no significant change thereafter. We analyzed the potential driving factors of SCA slowing‐down, with an ensemble of dynamic global vegetation models (DGVMs) coupled with an atmospheric transport model. We found that slowing‐down of SCA at MLO is primarily explained by response of net biome productivity (NBP) to climate change, and by changes in atmospheric circulations. Through NBP, climate change increases SCA at MLO before the 1980s and decreases it afterwards. The effect of climate change on the slowing‐down of SCA at MLO is mainly exerted by intensified drought stress acting to offset the acceleration driven by CO2 fertilization. This challenges the view that CO2 fertilization is the dominant cause of emergent SCA trends at northern sites south of 40°N. The contribution of agricultural intensification on the deceleration of SCA at MLO was elusive according to land–atmosphere CO2 flux estimated by DGVMs and atmospheric inversions. Our results also show the necessity to adequately account for changing circulation patterns in understanding carbon cycle dynamics observed from atmospheric observations and in using these observations to benchmark DGVMs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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25. Janus kinase inhibitors suppress cancer cachexia‐associated anorexia and adipose wasting in mice.
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Arora, Gurpreet K., Gupta, Arun, Guo, Tong, Gandhi, Aakash Y., Laine, Aaron, Williams, Dorothy L., Ahn, Chul, Iyengar, Puneeth, and Infante, Rodney E.
- Published
- 2020
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26. Comparison of forest above‐ground biomass from dynamic global vegetation models with spatially explicit remotely sensed observation‐based estimates.
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Yang, Hui, Ciais, Philippe, Santoro, Maurizio, Huang, Yuanyuan, Li, Wei, Wang, Yilong, Bastos, Ana, Goll, Daniel, Arneth, Almut, Anthoni, Peter, Arora, Vivek K., Friedlingstein, Pierre, Harverd, Vanessa, Joetzjer, Emilie, Kautz, Markus, Lienert, Sebastian, Nabel, Julia E. M. S., O'Sullivan, Michael, Sitch, Stephen, and Vuichard, Nicolas
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FOREST biomass ,FOREST density ,REGRESSION analysis ,REMOTE sensing ,PLANT biomass ,POPULATION density - Abstract
Gaps in our current understanding and quantification of biomass carbon stocks, particularly in tropics, lead to large uncertainty in future projections of the terrestrial carbon balance. We use the recently published GlobBiomass data set of forest above‐ground biomass (AGB) density for the year 2010, obtained from multiple remote sensing and in situ observations at 100 m spatial resolution to evaluate AGB estimated by nine dynamic global vegetation models (DGVMs). The global total forest AGB of the nine DGVMs is 365 ± 66 Pg C, the spread corresponding to the standard deviation between models, compared to 275 Pg C with an uncertainty of ~13.5% from GlobBiomass. Model‐data discrepancy in total forest AGB can be attributed to their discrepancies in the AGB density and/or forest area. While DGVMs represent the global spatial gradients of AGB density reasonably well, they only have modest ability to reproduce the regional spatial gradients of AGB density at scales below 1000 km. The 95th percentile of AGB density (AGB95) in tropics can be considered as the potential maximum of AGB density which can be reached for a given annual precipitation. GlobBiomass data show local deficits of AGB density compared to the AGB95, particularly in transitional and/or wet regions in tropics. We hypothesize that local human disturbances cause more AGB density deficits from GlobBiomass than from DGVMs, which rarely represent human disturbances. We then analyse empirical relationships between AGB density deficits and forest cover changes, population density, burned areas and livestock density. Regression analysis indicated that more than 40% of the spatial variance of AGB density deficits in South America and Africa can be explained; in Southeast Asia, these factors explain only ~25%. This result suggests TRENDY v6 DGVMs tend to underestimate biomass loss from diverse and widespread anthropogenic disturbances, and as a result overestimate turnover time in AGB. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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27. Transmission of Pantoea agglomerans—A paratransgenic control agent—Within a Homalodisca vitripennis population.
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Arora, Arinder K., Miller, Thomas A., and Durvasula, Ravi V.
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XYLELLA fastidiosa , *ARTHROPOD vectors , *PEST control - Abstract
Paratransgenic control of pests can be an alternative to chemical control, which is associated with environmental contamination, and higher input cost. We have recently developed paratransgenic control strategy to block transmission of the Pierce's disease pathogen—Xylella fastidiosa by its arthropod vector—Homalodisca vitripennis (the glassy‐winged sharpshooter) using antimicrobial peptide‐expressing strains of Pantoea agglomerans. In the present study, we report horizontal transmission of one of such P. agglomerans strains from H. vitripennis. This process indicates that P. agglomerans can self‐sustain in a population of H. vitripennis and, thus, can provide paratransgenic control of X. fastidiosa in field. These results also provide basis for future field studies. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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28. Cytological diagnosis of juvenile xanthogranuloma: A rare histiocytic disorder.
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Chauhan, Shivangi, Diwaker, Preeti, Singh, Aakanksha, Gogoi, Priyanka, and Arora, Vinod K.
- Published
- 2020
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29. Pulmonary hypertension: Molecular aspects of current therapeutic intervention and future direction.
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Arora, Taruna K., Arora, Amit K., Sachdeva, Monika K., Rajput, Satyendra K., and Sharma, Arun K.
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PULMONARY hypertension , *MOLECULAR biology , *DISEASE prevalence , *ENDOTHELIN receptors , *PHOSPHODIESTERASE-5 inhibitors , *HYPERTENSION risk factors - Abstract
Pulmonary hypertension (PH) is a life‐threatening lung disorder with towering prevalence and risk for future has been gradually rising worldwide. Even, no specific medications are available for pulmonary hypertension; various classes of treatment based upon the origin and magnitude of hypertension are still used for the treatment of PH. Consideration of molecular or signaling modulation is the imperative approach that can offer a new notion for prevalent pharmacotherapeutic agents. Instead of concurrent targets, including endothelin receptor antagonists (ETA/ETB), phosphodiesterase 5 inhibitor (PDF‐5), calcium channel blockers, anticoagulants, diuretics, and long acting prostacyclin analog, recent scientific reports revealed the numerous potential alternative therapeutic approaches that can significantly target the pathological signaling alteration associated with PH. Understanding precise molecular cascade involved in PH can be useful for designing preclinical animal experiments and human clinical trials to evaluate target specific novel therapeutic interventions for the treatment of PH. In this review, we discussed the possible molecular signaling involved in the pathogenesis of PH and detailed account of the current status of medications employed for the treatment of PH. Moreover, the newly identified potential target sites and alternative approaches for treating the PH have been discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
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30. COVID‐19 infection in a child following liver transplantation.
- Author
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Sindwani, G., Abhinaya, S. V., Arora, M. K., Pamecha, V., and Lal, B. B.
- Abstract
Summary: COVID‐19 infection immediately after liver transplantation presents a unique and challenging situation. In this report, we present the case of an 11‐year‐old girl who underwent emergency living donor liver transplantation for acute liver failure. After an uneventful intra‐operative course, the patient was transferred to the intensive care unit. On the second postoperative day, the patient developed unexplained severe hypoxia. A polymerase chain reaction test was positive for SARS‐CoV‐2 virus and a hypercoagulable state was indicated by laboratory investigations. Despite therapies such as mechanical ventilation and therapeutic anticoagulation, further clinical deterioration occurred. On the seventh postoperative day, the patient’s pupils were fully dilated bilaterally and unreactive to light, and brain death was later confirmed. This report highlights unique challenges pertaining to oxygenation, coagulation and immunosuppression after liver transplantation in a child with COVID‐19. Hypoxia of unknown origin in the postoperative period should prompt consideration of COVID‐19 as a possible cause. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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31. Change in serum levels of inflammatory markers reflects response of percutaneous catheter drainage in symptomatic fluid collections in patients with acute pancreatitis.
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Mallick, Bipadabhanjan, Tomer, Shallu, Arora, Sunil K, Lal, Anupam, Dhaka, Narendra, Samanta, Jayanta, Sinha, Saroj K, Gupta, Vikas, Yadav, Thakur Deen, and Kochhar, Rakesh
- Subjects
PANCREATITIS ,SERUM ,C-reactive protein - Abstract
Background: Percutaneous catheter drainage (PCD) is used as the first step in the management of symptomatic fluid collections in patients with acute pancreatitis (AP). There are limited data on the effect of PCD on inflammatory markers. Aim: To study the effects of PCD on serum levels of C‐reactive protein (CRP), IL‐6, and IL‐10 and its correlation with the outcome. Methods: Consecutive patients of AP with symptomatic fluid collections undergoing PCD were evaluated for serum levels of CRP, IL‐6, and IL‐10 before PCD and at 3 and 7 days after PCD. Resolution of organ failure (OF), sepsis, and pressure symptoms was considered to demonstrate the success of PCD. Changes in levels following PCD were correlated with outcome. Results: Indications of PCD in 59 patients (age 38.9 ± 13.17 years, 49 male) were suspected/documented infected pancreatic necrosis (n = 45), persistent OF (n = 40), and pressure symptoms (n = 7). A total of 49 (83.1%) patients improved with PCD, five patients required surgery, and six died. A significant difference was noted between baseline levels of CRP (P = 0.026) and IL‐6 (P = 0.013) among patients who improved compared to those who worsened following PCD. Significant decrease (P < 0.01) of all three markers on day 3 of PCD insertion, with further decrease (P < 0.01) on day 7, was noted. The percentage of the decrease of IL‐6 levels on day 3 and of CRP on day 7 correlated with the outcome. Conclusion: PCD is associated with a significant decrease in CRP, IL‐6, and IL‐10 levels. Percentage decrease in IL‐6 on day 3 and CRP on day 7 correlated with the outcome of patients managed with PCD. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
32. Implementation of the MILAN system for reporting salivary gland cytopathology: Interobserver concordance and cytohistological correlation of discordant cases.
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Garg, Neha, Diwaker, Preeti, Pathak, Priya, Aggarwal, Divya, and Arora, Vinod K.
- Published
- 2019
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33. Clinical and cortical decline in the aphasic variant of Alzheimer's disease.
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Rogalski, Emily Joy, Sridhar, Jaiashre, Martersteck, Adam, Rader, Benjamin, Cobia, Derin, Arora, Anupa K., Fought, Angela J., Bigio, Eileen H., Weintraub, Sandra, Mesulam, Marek‐Marsel, and Rademaker, Alfred
- Abstract
Introduction: Primary progressive aphasia (PPA) displays variable progression trajectories that require further elucidation. Methods: Longitudinal quantitation of atrophy and language over 12 months was completed for PPA patients with and without positive amyloid PET (PPAAβ+ and PPAAβ−), an imaging biomarker of underlying Alzheimer's disease. Results: Over 12 months, both PPA groups showed significantly greater cortical atrophy rates in the left versus right hemisphere, with a more widespread pattern in PPAAβ+. The PPAAβ+ group also showed greater decline in performance on most language tasks. There was no obligatory relationship between the logopenic PPA variant and amyloid status. Effect sizes from quantitative MRI data were more robust than neuropsychological metrics. Discussion: Preferential language network neurodegeneration is present in PPA irrespective of amyloid status. Clinical and anatomical progression appears to differ for PPA due to Alzheimer's disease versus non–Alzheimer's disease neuropathology, a distinction that may help to inform prognosis and the design of intervention trials. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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34. Oral Infection Involving Nocardia and Actinomyces: A Case Report.
- Author
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Arora, Kirandeep K., Gruwell, Scott F., and Cobb, Charles M.
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NOCARDIA , *ACTINOMYCES , *DENTAL implants , *MOUTH infections , *IMMUNOCOMPROMISED patients - Abstract
Introduction: Both Actinomyces and Nocardia are Gram‐positive microbes characterized by a filamentous morphology. Both can be causative agents in slowly progressive, localized, or disseminated infections that are rare and typically occur in immunocompromised patients. Oral infections involving both microorganisms are very rare. Case Presentation: A black male with a history of Type 2 diabetes was referred with a chief complaint of a persistent 3 mm × 3 mm swelling facial to the mandibular central incisors. The swelling was asymptomatic except for occasional discharge of purulent exudate. Examination revealed 5‐ to 6‐mm mesio‐lingual and mid‐lingual probing depths. Radiographs revealed a well‐defined radiolucency between the roots of teeth #24 and #25. A full‐thickness gingival flap was reflected exposing an oval‐shaped bony defect, which was debrided and the contents submitted for microscopic examination. The resulting defect was filled with demineralized freeze‐dried bone allograft (DFDBA) and capped with calcium sulfate. The patient was prescribed amoxicillin and 0.12% chlorhexidine gluconate mouthrinse. Examination of the biopsied tissue revealed both Actinomyces and Nocardia microorganisms. The patient was followed for 24 months and remains symptom‐free with noted radiographic evidence of bone fill in the lesion area. Conclusions: This may be the first published report of an oral infection featuring both Actinomyces and Nocardia. The case reinforces the importance of microscopic examination of biopsy material removed from unusual and persistent pathologic lesions that are destructive of bone. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
35. Evaluating GPP and Respiration Estimates Over Northern Midlatitude Ecosystems Using Solar‐Induced Fluorescence and Atmospheric CO2 Measurements.
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Byrne, B., Wunch, D., Jones, D. B. A., Strong, K., Deng, F., Baker, I., Köhler, P., Frankenberg, C., Joiner, J., Arora, V. K., Badawy, B., Harper, A. B., Warneke, T., Petri, C., Kivi, R., and Roehl, C. M.
- Subjects
CLIMATE change ,CARBON dioxide ,FOREST management ,BIBLIOMETRICS ,ECOLOGICAL disturbances - Abstract
On regional to global scales, few constraints exist on gross primary productivity (GPP) and ecosystem respiration (Re) fluxes. Yet constraints on these fluxes are critical for evaluating and improving terrestrial biosphere models. In this study, we evaluate the seasonal cycle of GPP, Re, and net ecosystem exchange (NEE) produced by four terrestrial biosphere models and FLUXCOM, a data‐driven model, over northern midlatitude ecosystems. We evaluate the seasonal cycle of GPP and NEE using solar‐induced fluorescence retrieved from the Global Ozone Monitoring Experiment‐2 and column‐averaged dry‐air mole fractions of CO2 (XCO2) from the Total Carbon Column Observing Network, respectively. We then infer Re by combining constraints on GPP with constraints on NEE from two flux inversions. An ensemble of optimized Re seasonal cycles is generated using five GPP estimates and two NEE estimates. The optimized Re curves generally show high consistency with each other, with the largest differences due to the magnitude of GPP. We find optimized Re exhibits a systematically broader summer maximum than modeled Re, with values lower during June–July and higher during the fall than Re. Further analysis suggests that the differences could be due to seasonal variations in the carbon use efficiency (possibly due to an ecosystem‐scale Kok effect) and to seasonal variations in the leaf litter and fine root carbon pool. The results suggest that the inclusion of variable carbon use efficiency for autotrophic respiration and carbon pool dependence for heterotrophic respiration is important for accurately simulating Re. Key Points: Top‐down constraints on ecosystem respiration are obtained by combining atmospheric CO2 and solar‐induced fluorescence observationsInferred ecosystem respiration suggests a systematically broader summer maximum than bottom‐up estimates over the northern midlatitudesInferred ecosystem respiration shows high sensitivity to the magnitude of gross primary productivity [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
36. Brain gene expression analyses in virgin and mated queens of fire ants reveal mating‐independent and socially regulated changes.
- Author
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Calkins, Travis L., Chen, Mei‐Er, Arora, Arinder K., Hawkings, Chloe, Tamborindeguy, Cecilia, and Pietrantonio, Patricia V.
- Subjects
FIRE ants ,JUVENILE hormones ,ANIMAL sexual behavior ,NUCLEIC acid isolation methods ,POLYMERASE chain reaction - Abstract
Abstract: Transcriptomes of dissected brains from virgin alate and dealate mated queens from polygyne fire ants (
Solenopsis invicta ) were analyzed and compared. Thirteen genes were upregulated in mated queen brain, and nine were downregulated. While many of the regulated genes were either uncharacterized or noncoding RNAs, those annotated genes included two hexamerin proteins, astakine neuropeptide, serine proteases, and serine protease inhibitors. We found that for select differentially expressed genes in the brain, changes in gene expression were most likely driven by the changes in physiological state (i.e., age, nutritional status, or dominance rank) or in social environment (released from influence of primer pheromone). This was concluded because virgins that dealated after being separated from mated queens showed similar patterns of gene expression in the brain as those of mated queens forhexamerin 1 ,astakine , andXR_850909 .Abaecin (XR_850725 ), however, appears upregulated only after mating. Therefore, our findings contribute to distinguish how specific gene networks, especially those influenced by queen primer pheromone, are regulated in queen ants. Additionally, to identify brain signaling pathways, we mined the fire ant genome and compiled a list of G‐protein‐coupled receptors (GPCRs). The expression level of GPCRs and other genes in the “genetic toolkit” in the brains of virgin alates and mated dealate queens is reported. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
37. Cytokeratin 20 immunocytochemistry on urine sediments: A potential low-cost adjunct to cytology in the diagnosis of low-grade urothelial carcinoma.
- Author
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Wadhwa, N., Diwaker, P., Lotha, N., Arora, V. K., and Singh, N.
- Subjects
TRANSITIONAL cell carcinoma ,URINALYSIS ,CYTOLOGY methodology ,BIOMARKERS ,IMMUNOCYTOCHEMISTRY ,BLADDER cancer ,BLADDER cancer diagnosis - Abstract
Background Urine cytology is the corner-stone for the diagnosis of urothelial neoplasia; however, a substantial proportion of low-grade carcinomas are reported as inconclusive owing to scant cellularity and subtle cytological features. Biomarkers applied on urine sediment smears of such patients are likely to be clinically relevant. Access to Food and Drug Administration approved urinary biomarkers in resource limited setting is poor. Detection of cytokeratin 20 ( CK20) in urine sediments, although still a research tool, is a promising marker as immunocytochemistry is performed regularly in several Indian laboratories. Objective We tested the clinical utility of CK20 immunocytochemistry as a potential low-cost adjunct to urine cytology in diagnosis of low-grade urothelial carcinoma. One hundred and fifty fresh, voided urine specimens from 42 cases of biopsy proven urothelial neoplasia (14 high grade, 28 combined low-grade [n=26]) and low malignant potential [n=2]), and 20 non-neoplastic lesions were included in the study sample. Results Confident diagnosis of malignancy was possible in five (17.8%) low-grade malignancies. Thirteen of 16 (81.3%) low-grade malignancies with inconclusive cytology showed positive CK20 expression. This reduced the proportion of low-grade cases with inconclusive cytology from 57.1% to 10.7% ( P=.021). In addition, we could correctly classify one case of bladder lithiasis with false positive urine cytology. Discrepant CK20 staining (positive) was seen in one patient with acute cystitis. Conclusions CK20 expression in non-umbrella cells is a robust marker of urinary bladder carcinoma. It has potential clinical utility for identification of low-grade urothelial malignancy with inconclusive cytological diagnosis. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
38. Lymphoepithelioma-like carcinoma of cervix.
- Author
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Rathore, Ruchi, Arora, Vinod K., and Singh, Bharat
- Published
- 2017
- Full Text
- View/download PDF
39. Improving the quality of survivorship for older adults with cancer.
- Author
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Mohile, Supriya G., Hurria, Arti, Cohen, Harvey J., Rowland, Julia H., Leach, Corinne R., Arora, Neeraj K., Canin, Beverly, Muss, Hyman B., Magnuson, Allison, Flannery, Marie, Lowenstein, Lisa, Allore, Heather G., Mustian, Karen M., Demark‐Wahnefried, Wendy, Extermann, Martine, Ferrell, Betty, Inouye, Sharon K., Studenski, Stephanie A., and Dale, William
- Subjects
CANCER prognosis ,DISEASES in older people ,QUALITY of life ,GERIATRICS ,MEDICAL care - Abstract
In May 2015, the Cancer and Aging Research Group, in collaboration with the National Cancer Institute and the National Institute on Aging through a U13 grant, convened a conference to identify research priorities to help design and implement intervention studies to improve the quality of life and survivorship of older, frailer adults with cancer. Conference attendees included researchers with multidisciplinary expertise and advocates. It was concluded that future intervention trials for older adults with cancer should: 1) rigorously test interventions to prevent the decline of or improve health status, especially interventions focused on optimizing physical performance, nutritional status, and cognition while undergoing cancer treatment; 2) use standardized care plans based on geriatric assessment findings to guide targeted interventions; and 3) incorporate the principles of geriatrics into survivorship care plans. Also highlighted was the need to integrate the expertise of interdisciplinary team members into geriatric oncology research, improve funding mechanisms to support geriatric oncology research, and disseminate high-impact results to the research and clinical community. In conjunction with the 2 prior U13 meetings, this conference provided the framework for future research to improve the evidence base for the clinical care of older adults with cancer. Cancer 2016;122:2459-68. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
40. Using the wayback machine to mine websites in the social sciences: A methodological resource.
- Author
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Arora, Sanjay K., Li, Yin, Youtie, Jan, and Shapira, Philip
- Subjects
- *
RESEARCH funding , *SOCIAL sciences , *WORLD Wide Web , *DATA mining , *DATA analysis - Abstract
Websites offer an unobtrusive data source for developing and analyzing information about various types of social science phenomena. In this paper, we provide a methodological resource for social scientists looking to expand their toolkit using unstructured web-based text, and in particular, with the Wayback Machine, to access historical website data. After providing a literature review of existing research that uses the Wayback Machine, we put forward a step-by-step description of how the analyst can design a research project using archived websites. We draw on the example of a project that analyzes indicators of innovation activities and strategies in 300 U.S. small- and medium-sized enterprises in green goods industries. We present six steps to access historical Wayback website data: (a) sampling, (b) organizing and defining the boundaries of the web crawl, (c) crawling, (d) website variable operationalization, (e) integration with other data sources, and (f) analysis. Although our examples draw on specific types of firms in green goods industries, the method can be generalized to other areas of research. In discussing the limitations and benefits of using the Wayback Machine, we note that both machine and human effort are essential to developing a high-quality data set from archived web information. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
41. Modeling the diurnal variability of respiratory fluxes in the Canadian Terrestrial Ecosystem Model (CTEM).
- Author
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Badawy, Bakr, Arora, Vivek K., Melton, Joe R., and Nassar, Ray
- Subjects
- *
ECOSYSTEM dynamics , *PHOTOSYNTHESIS , *CARBON dioxide , *BIOSPHERE , *PLANTS - Abstract
The Canadian Terrestrial Ecosystem Model (CTEM) coupled to the Canadian Land Surface Scheme (CLASS) is a dynamic vegetation model that incorporates photosynthesis and respiration submodules among many other physiological processes of the terrestrial biosphere. While the photosynthesis and leaf respiration submodules of CTEM operate at a time step of 30 min, other respiratory fluxes are estimated at a daily time step using the daily-averaged values of canopy and soil temperature, and soil moisture content. Here we modify CTEM to be able to simulate the diurnal variation of ecosystem respiratory fluxes caused by the diurnal variation in the driving climate data. Simulating respiration at a 30 min time step changed the equilibrium states of primary carbon pools and fluxes. This required changes to some of the model's parameters in order to realistically simulate the equilibrium values of carbon pools and fluxes. The resulting estimated daily and annual carbon fluxes from the modified and original CTEM are similar with small relative differences. The similar annual cycles of daily values of primary CO2 fluxes confirm that modeling the respiratory fluxes at a subdaily time step does not affect the annual cycles of these fluxes. We also demonstrate that the modified version of the model is able to simulate the diurnal cycle of net ecosystem exchange of CO2 fluxes that are broadly comparable to observation-based estimates at two flux tower sites and exhibit realistic seasonal patterns. Limitations remain in the modeled diurnal patterns of primary land-atmosphere CO2 fluxes which will form the basis of further model improvements. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
42. Potential near-future carbon uptake overcomes losses from a large insect outbreak in British Columbia, Canada.
- Author
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Arora, Vivek K., Peng, Yiran, Kurz, Werner A., Fyfe, John C., Hawkins, Barbara, and Werner, Arelia T.
- Published
- 2016
- Full Text
- View/download PDF
43. The sensitivity of simulated competition between different plant functional types to subgrid-scale representation of vegetation in a land surface model.
- Author
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Shrestha, R. K., Arora, V. K., and Melton, J. R.
- Published
- 2016
- Full Text
- View/download PDF
44. The rationale for patient-reported outcomes surveillance in cancer and a reproducible method for achieving it.
- Author
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Smith, Tenbroeck G., Castro, Kathleen M., Troeschel, Alyssa N., Arora, Neeraj K., Lipscomb, Joseph, Jones, Shelton M., Treiman, Katherine A., Hobbs, Connie, McCabe, Ryan M., and Clauser, Steven B.
- Subjects
CANCER treatment ,QUALITY of life ,SYMPTOMS ,PUBLIC health surveillance ,PATIENTS' attitudes ,BREAST tumor treatment ,BREAST tumors ,FATIGUE (Physiology) ,COLON tumors ,INTERNATIONAL relations ,MEDICAL quality control ,HEALTH outcome assessment ,PAIN ,PATIENT satisfaction ,RESEARCH evaluation ,STATISTICAL sampling ,SELF-evaluation ,PSYCHOLOGICAL stress ,TREATMENT effectiveness ,PATIENT selection ,DISEASE complications ,PSYCHOLOGY ,TUMOR treatment ,CANCER & psychology - Abstract
Patient-reported outcomes (PROs) measure quality of life, symptoms, patient functioning, and patient perceptions of care; they are essential for gaining a full understanding of cancer care and the impact of cancer on people's lives. Repeatedly captured facility-level and/or population-level PROs (PRO surveillance) could play an important role in quality monitoring and improvement, benchmarking, advocacy, policy making, and research. This article describes the rationale for PRO surveillance and the methods of the Patient Reported Outcomes Symptoms and Side Effects Study (PROSSES), which is the first PRO study to use the American College of Surgeons Commission on Cancer's Rapid Quality Reporting System to identify patients and manage study data flow. The American Cancer Society, the National Cancer Institute, the Commission on Cancer, and RTI International collaborated on PROSSES. PROSSES was conducted at 17 cancer programs that participated in the National Cancer Institute Community Cancer Centers Program among patients diagnosed with locoregional breast or colon cancer. The methods piloted in PROSSES were successful as demonstrated by high eligibility (93%) and response (61%) rates. Differences in clinical and demographic characteristics between respondents and nonrespondents were mostly negligible, with the exception that non-white individuals were somewhat less likely to respond. These methods were consistent across cancer centers and reproducible over time. If repeated and expanded, they could provide PRO surveillance data from patients with cancer on a national scale. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
45. Impact of surgery and chemotherapy on the quality of life of younger women with breast carcinoma: a prospective study.
- Author
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Arora, Neeraj K., Gustafson, David H., Hawkins, Robert P., McTavish, Fiona, Cella, David F., Pingree, Suzanne, Mendenhall, John H., Mahvi, David M., Arora, N K, Gustafson, D H, Hawkins, R P, McTavish, F, Cella, D F, Pingree, S, Mendenhall, J H, and Mahvi, D M
- Published
- 2001
- Full Text
- View/download PDF
46. Study of water cloud model vegetation descriptors in estimating soil moisture in Solani catchment.
- Author
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Kumar, Kamal, Suryanarayana Rao, Hari Prasad, and Arora, M. K.
- Subjects
SOIL moisture measurement ,VEGETATION classification ,SYNTHETIC apertures ,BACKSCATTERING ,GENETIC algorithms ,LEAF area index - Abstract
Water cloud model (WCM) relates the backscatter coefficient ( σ
o ) with soil moisture. The backscatter coefficient includes the backscatter coefficient due to vegetation ( σo veg ), and the backscatter coefficient due to soil ( σo soil ). The σo veg of WCM depends upon vegetation characteristics. The present study is aimed to investigate the effect of different vegetation descriptors in estimating soil moisture from WCM. The study is carried out in Solani River catchment of India. Envisat Advanced Synthetic Aperture Radar (ASAR) images of three dates were acquired for the study. The field data, volumetric soil moisture from the upper 0-10 cm soil layer, soil texture, soil surface roughness, leaf area index (LAI), leaf water area index, normalized plant water content and average plant height corresponding to satellite pass dates were collected. Genetic algorithm optimization technique is used to estimate the WCM vegetation parameters. The use of LAI as vegetation descriptor results in minimum root mean square error (RMSE) of 1.77 dB between WCM computed backscatter and Envisat ASAR observed backscatter. Also, use of LAI in WCM as vegetation descriptor results in the least RMSE of 4.19%, between estimated and observed soil moisture for the first field campaign, whereas it was 5.64% for the last field campaign which was undertaken after 35 days of first campaign. It is concluded that LAI can be treated as the best vegetation descriptor in studies retrieving soil moisture and backscatter from microwave remote sensing data. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]- Published
- 2015
- Full Text
- View/download PDF
47. The role of families in decisions regarding cancer treatments.
- Author
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Hobbs, Gabriela S., Landrum, Mary Beth, Arora, Neeraj K., Ganz, Patricia A., van Ryn, Michelle, Weeks, Jane C., Mack, Jennifer W., and Keating, Nancy L.
- Subjects
CANCER treatment ,DECISION making ,FAMILIES ,SOCIODEMOGRAPHIC factors ,RACIAL differences - Abstract
BACKGROUND Shared decision-making is an important component of patient-centered care and is associated with improved outcomes. To the authors' knowledge, little is known concerning the extent and predictors of the involvement of a patient's family in decisions regarding cancer treatments. METHODS The Cancer Care Outcomes Research and Surveillance (CanCORS) Consortium is a large, multiregional, prospective cohort study of the cancer care and outcomes of patients with lung and colorectal cancer. Participants reported the roles of their families in decision-making regarding treatment. Multinomial logistic regression was used to assess patient factors associated with family roles in decisions. RESULTS Among 5284 patients, 80 (1.5%) reported family-controlled decisions, with the highest adjusted rates (12.8%) noted among non-English-speaking Asians. Among the 5204 remaining patients, 49.4% reported equally sharing decisions with family, 22.1% reported some family input, and 28.5% reported little family input. In adjusted analyses, patients who were married, female, older, and insured more often reported equally shared decisions with family (all P <.001). Adjusted family involvement varied by race/ethnicity and language, with Chinese-speaking Asian (59.8%) and Spanish-speaking Hispanic (54.8%) patients equally sharing decisions with family more often than white individuals (47.6%). Veterans Affairs patients were least likely to report sharing decisions with family, even after adjustment for marital status and social support ( P <.001). CONCLUSIONS The majority of patients with newly diagnosed lung or colorectal cancer involve family members in treatment decisions. Non-English-speaking Asians and Hispanics rely significantly on family. Further studies are needed to determine the impact of family involvement in treatment decisions on outcomes; until then, physicians should consider eliciting patients' preferences for family involvement. Cancer 2015;121:1079-1087. © 2015 American Cancer Society. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
48. Cancer survivors' disclosure of complementary health approaches to physicians: The role of patient-centered communication.
- Author
-
Sohl, Stephanie J., Borowski, Laurel A., Kent, Erin E., Smith, Ashley Wilder, Oakley‐Girvan, Ingrid, Rothman, Russell L., and Arora, Neeraj K.
- Subjects
MEDICAL communication ,PATIENT-centered care ,CANCER research ,DISCLOSURE ,PHYSICIAN-patient relations - Abstract
BACKGROUND Cancer survivors' disclosure of complementary health approaches (CHAs) to their follow-up care physicians is necessary to ensure the safe and optimal use of such approaches. Rates of disclosure of CHAs are variable and may be facilitated by patient-centered communication. METHODS This cross-sectional study conducted in 2003-2004 examined a population-based sample of leukemia, colorectal, and bladder cancer survivors (n=623) who were 2 to 5 years after their diagnosis. A subset of participants who reported using CHAs (n=196) was analyzed with multivariate logistic regression to examine the association between patients' perceptions of their physician's patient-centered communication (ie, information exchange, affective behavior, knowledge of patients as persons) and patients' disclosure of CHA use to their physician with adjustments for physician, patient, and patient-physician relationship factors. RESULTS Thirty-one percent of the full sample used CHAs, and 47.6% of CHA users disclosed their use to their physicians. Disclosure was significantly associated with patient-centered communication even with adjustments for hypothesized covariates (odds ratio [OR], 1.37; 95% confidence interval [CI], 1.09-1.71). Perceived physician knowledge of the patient as a person (OR, 1.28; 95% CI, 1.10-1.48) and information exchange (OR, 1.27; 95% CI, 1.02-1.60) were the aspects of patient-centered communication that contributed to this association. The main reason for nondisclosure assessed in the survey was that survivors did not think that it was important to discuss CHAs (67.0%). A majority of physicians encouraged continued use of CHAs when they were disclosed (64.8%). CONCLUSIONS Results support the idea that improving the overall patient centeredness of cancer follow-up care and improving the disclosure of CHA use are potentially synergistic clinical goals. Cancer 2015;121:900-907. © 2014 American Cancer Society. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
49. Whole-of-society monitoring framework for sugar, salt, and fat consumption and noncommunicable diseases in India.
- Author
-
Arora, Narendra K., Pillai, Rakesh, Dasgupta, Rajib, and Garg, Priyanka Rani
- Subjects
- *
FOOD consumption , *SUGAR content of food , *SALT content of food , *FAT content of food , *NON-communicable diseases , *DISEASE prevalence - Abstract
India has experienced a rising prevalence of cardiometabolic risk factors in the past 15 years: the prevalence of diabetes has increased from 5.9% to 9.1%, hypertension from 17.2% to 29.2%, and obesity from 4% to 15%. The increase is among all socioeconomic groups and in urban and rural populations, though the quantum of change varies. A concomitant increase in per capita consumption of sugar from 22 to 55.3 g/day and total fat from 21.2 to 54 g/day was observed, with significant differences between states of high and low human development index (HDI). Per capita consumption of sugar, salt, and fat is consistently and significantly associated with overweight and obesity but variably associated with the occurrence of hypertension and diabetes. Market research shows that approximately 50-60% of total salt, sugar, and fat in Indian markets is procured by bulk purchasers, generally for manufacturing processed food items. This sector of the Indian economy is among the fastest growing, with several policy incentives. It is not clear from most of the data sets whether available information on per capita sugar, salt, and fat consumption has considered the contribution of processed and ready-to-eat food items. The unprecedented changes of rapid urbanization, mechanization, and globalization demand close monitoring of social, developmental, and economic determinants. This paper provides pieces of evidence to justify a whole-of-society (WoS) framework for monitoring the inputs, processes, and behavioral components of the National Programme for Prevention and Control of Cancer, Diabetes, Cardiovascular Disease and Stroke (NPCDCS) in India. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
50. Agriculture, health, and wealth convergence: bridging traditional food systems and modern agribusiness solutions.
- Author
-
Dubé, Laurette, Webb, Patrick, Arora, Narendra K., and Pingali, Prabhu
- Subjects
AGRICULTURAL economics ,TRADITIONAL farming ,CONSUMPTION (Economics) ,DISTRIBUTION (Economic theory) ,INNOVATIONS in business ,TWENTY-first century - Abstract
The causes of many vexing challenges facing 21st-century society are at the nexus of systems involved in agriculture, health and wealth production, consumption, and distribution. Using food as a test bed, and on the basis of emerging roadmaps that set achievable objectives over a 1- to 3-year horizon, we introduce this special feature with convergence thinking and practice at its core. Specifically, we discuss academic papers structured around four themes: (1) evidence for a need for convergence and underlying mechanisms at the individual and societal levels; (2) strategy for mainstreaming convergence as a driver of business engagement and innovation; (3) convergence in policy and governance; (4) convergence in metrics and methods. Academic papers under each theme are accompanied by a roadmap paper reporting on the current status of concrete transformative convergence-building projects associated with that theme. We believe that the insights provided by these papers have the potential to enable all actors throughout society to singly and collectively work to build supply and demand for nutritious food, in both traditional and modern food systems, while placing the burdens of malnutrition and ill health on their core strategic agendas. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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