615 research outputs found
Potential hydrologic changes in the Amazon by the end of the 21st century and the groundwater buffer
This study contributes to the discussions on the future of the Amazon rainforest under a
projected warmer-drier climate from the perspectives of land hydrology. Using IPCC
HadGEM2-ES simulations of the present and future Amazon climate to drive a land hydrology
model that accounts for groundwater constraint on land drainage, we assess potential hydrologic
changes in soil water, evapotranspiration (ET), water table depth, and river discharge, assuming
unchanged vegetation. We ask: how will ET regimes shift at the end of the 21st century, and will
the groundwater help buffer the anticipated water stress in some places-times? We conducted
four 10 yr model simulations, at the end of 20th and 21st century, with and without the
groundwater. Our model results suggest that, first, over the western and central Amazon, ET will
increase due to increased potential evapotranspiration (PET) with warmer temperatures, despite a
decrease in soil water; that is, ET will remain PET or atmospheric demand-limited. Second, in
the eastern Amazon dry season, ET will decrease in response to decreasing soil water, despite
increasing PET demand; that is, ET in these regions-seasons will remain or become more soil
water or supply-limited. Third, the area of water-limited regions will likely expand in the eastern
Amazonia, with the dry season, as indicated by soil water store, even drier and longer. Fourth,
river discharge will be significantly reduced over the entire Amazon but particularly so in the
southeastern Amazon. By contrasting model results with and without the groundwater, we found
that the slow soil drainage constrained by shallow groundwater can buffer soil water stress,
particularly in southeastern Amazon dry season. Our model suggests that, if groundwater
buffering effect is accounted for, the future Amazon water stress may be less than that projected
by most climate modelsFunding comes from NSF (NSF-AGS-1045110), US EPA (EPA-STAR-RD834190) and the European Commission FP7 (EartH2Observe). Computation used the NCAR's Computational and Information Systems Laboratory, sponsored by NSF and other agenciesS
PCR Based Genotyping of Lulu Cattle of Nepal for A1, A2 Type Beta-caseins
Lulu is an indigenous breed of cattle (Bos taurus) found in high altitude regions of western Nepal. Population of Lulu cattle has been declining due to introgression with other exotic breeds to increase milk productivity. Here we aimed at finding potential approach for conserving Lulu cattle and its assets by studying the milk contents and investigating which variant of beta-casein protein is present in this breed. Beta caseins are an abundant protein in cow milk with A1 and A2 being the most common genetic variants of this protein. Consumption of A1 type of milk has numerous health-related complications whereas A2 type of milk has numerous human health promoting factors. We used restriction fragment length polymorphism (RFLP) for determining the A1 and A2 variant of beta casein in Lulu cattle. For performing DNA extraction, we collected (n = 18) blood samples of Lulu from Mustang and (n=17) Nepal Agriculture research council farm. The amplified fragments in 3% agarose at 251bp and 213bp respectively confirmed the presence of both A1 and A2 gene in Lulu; however, A2 was of greater abundance. Our study indicated that Lulu has A2 variant of beta-casein predominantly. The gene frequency of A1A1 is 0, A1A2 is 0.06 and A2A2 is 0.94. We further found that the allele frequency of A1 and A2 is 0.03 and 0.97 respectively. We designed special primer for sequencing CSN2 genes since A2 type beta casein gene was predominantly seen on Lulu. The sequencing result further supports our RFLP result as most of our samples have “C” nucleotide SNP in amplified CSN2 gene sequence. The Chi-square value of the current study is 0.04 which supports Hardy-Weinberg equilibrium inferring that Lulu cattle are still in the pure state, where there is no genetic introgression with the exotic breed for the sake of improvement of productivity
Comparative studies of the spectroscopic properties of nd3+: YAG nanocrystals transparent ceramic and single crystal
Detailed comparative spectroscopic studies of Nd3+ doped YAG nanocrystals, transparent ceramic and single crystal have been performed. Although most of the radiative spectral properties of Nd3+ are almost in good agreement between the three hosts, the non-radiative losses are significantly high in nanocrystals, which are attributed due to the presence of large amount of hydroxyl groups on the nanocrystals surface which deteriorates the quality of the material for laser applications. In addition, wavelength dependent scattering loss for the Nd3+ doped YAG nanocrystals is found significantly high compared to those of Nd3+ doped single crystal and ceramic. © 2012 Optical Society of America
Dataset for electronic and optical properties of Y2O2S and Er dopped Y2O2S calculated using density functional theory and simulated x-ray near edge spectra
The computational data presented in this paper refer to the research article “Optical properties and simulated x-ray near edge spectra for Y2O2S and Er doped Y2O2S”. We present the data used to calculate the structural, electronic, and optical properties of the Y2O2S and its Er+3 doped counterparts at various concentrations using density functional theory (DFT) and simulated X-ray near edge (XANES) spectra. We report electronic information from DFT and DFT+U generated from the Vienna Ab initio Simulation Package (VASP) using PAW pseudopotentials. We also report VASP calculated optical properties for the host Y2O2S using the independent particle approximation (IPA), the random phase approximation (RPA), the many-body GW0 approximation, and the Bethe-Salpeter equation (BSE) approximation, under the 10-atom unit cell. The IPA calculations are repeated using the 80-atom unit cell for both the host Y2O2S and the Y2O2S:Er+3 counterparts. The optical properties data include the frequency-dependent real and imaginary parts of the dielectric function, the absorption and extinction coefficients, the refractive index, and the reflectivity. FEFF10 XANES calculations are performed on the Y K-, L1-, L2-, and L3-edges, as well as on the Er M5-edge
Predicting the Effect of Indirect Cell Kill in the Treatment of Multiple Brain Metastases via Single-Isocenter/Multitarget Volumetric Modulated Arc Therapy Stereotactic Radiosurgery
PURPOSE: Due to spatial uncertainty, patient setup errors are of major concern for radiosurgery of multiple brain metastases (m-bm) when using single-isocenter/multitarget (SIMT) volumetric modulated arc therapy (VMAT) techniques. However, recent clinical outcome studies show high rates of tumor local control for SIMT-VMAT. In addition to direct cell kill (DCK), another possible explanation includes the effects of indirect cell kill (ICK) via devascularization for a single dose of 15 Gy or more and by inducing a radiation immune intratumor response. This study quantifies the role of indirect cell death in dosimetric errors as a function of spatial patient setup uncertainty for stereotactic treatments of multiple lesions.
MATERIAL AND METHODS: Nine complex patients with 61 total tumors (2-16 tumors/patient) were planned using SIMT-VMAT with geometry similar to HyperArc with a 10MV-FFF beam (2400 MU/min). Isocenter was placed at the geometric center of all tumors. Average gross tumor volume (GTV) and planning target volume (PTV) were 1.1 cc (0.02–11.5) and 1.9 cc (0.11–18.8) with an average distance to isocenter of 5.4 cm (2.2–8.9). The prescription was 20 Gy to each PTV. Plans were recalculated with induced clinically observable patient setup errors [±2 mm, ±2o] in all six directions. Boolean structures were generated to calculate the effect of DCK via 20 Gy isodose volume (IDV) and ICK via 15 Gy IDV minus the 20 Gy IDV. Contributions of each IDV to the PTV coverage were analyzed along with normal brain toxicity due to the patient setup uncertainty. Induced uncertainty and minimum dose covering the entire PTV were analyzed to determine the maximum tolerable patient setup errors to utilize the ICK effect for radiosurgery of m-bm via SIMT-VMAT.
RESULTS: Patient setup errors of 1.3 mm /1.3° in all six directions must be maintained to achieve PTV coverage of the 15 Gy IDV for ICK. Setup errors of ±2 mm/2° showed clinically unacceptable loss of PTV coverage of 29.4 ± 14.6% even accounting the ICK effect. However, no clinically significant effect on normal brain dosimetry was observed.
CONCLUSIONS: Radiosurgery of m-bm using SIMT-VMAT treatments have shown positive clinical outcomes even with small residual patient setup errors. These clinical outcomes, while largely due to DCK, may also potentially be due to the ICK. Potential mechanisms, such as devascularization and/or radiation-induced intratumor immune enhancement, should be explored to provide a better understanding of the radiobiological response of stereotactic radiosurgery of m-bm using a SIMT-VMAT plan
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The economic burden of multimorbidity: Protocol for a systematic review
Data Availability: No datasets were generated or analysed during the current study. All relevant data from this study will be made available upon study completion.Supporting information is available online at: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0301485#sec019 .Multimorbidity, also known as multiple long-term conditions, leads to higher healthcare utilisation, including hospitalisation, readmission, and polypharmacy, as well as a financial burden to families, society, and nations. Despite some progress, the economic burden of multimorbidity remains poorly understood. This paper outlines a protocol for a systematic review that aims to identify and synthesise comprehensive evidence on the economic burden of multimorbidity, considering various definitions and measurements of multimorbidity, including their implications for future cost-of-illness analyses. The review will include studies involving people of all ages with multimorbidity without any restriction on location and setting. Cost-of-illness studies or studies that examined economic burden including model-based studies will be included, and economic evaluation studies will be excluded. Databases including Scopus (that includes PubMed/MEDLINE), Web of Science, CINAHL Plus, PsycINFO, NHS EED (including the HTA database), and the Cost-Effectiveness Analysis Registry, will be searched until March 2024. The risk of bias within included studies will be independently assessed by two authors using appropriate checklists. A narrative synthesis of the main characteristics and results, by definitions and measurements of multimorbidity, will be conducted. The total economic burden of multimorbidity will be reported as mean annual costs per patient and disaggregated based on counts of diseases, disease clusters, and weighted indices. The results of this review will provide valuable insights for researchers into the key cost components and areas that require further investigation in order to improve the rigour of future studies on the economic burden of multimorbidity. Additionally, these findings will broaden our understanding of the economic impact of multimorbidity, inform us about the costs of inaction, and guide decision-making regarding resource allocation and cost-effective interventions. The systematic review’s results will be submitted to a peer-reviewed journal, presented at conferences, and shared via an online webinar for discussion.The author(s) received no specific funding for this work. This study is part of the first author's PhD project and that the first author is sponsored by the Department of Health Sciences at Brunel University London
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Effectiveness of integrated care interventions for patients with long-term conditions: a review of systematic reviews
Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer- reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.Correction notice This article has been corrected since it was first published online. The corresponding author has been updated to Nana Anokye and the licence has been updated to CC- BY.Copyright © Author(s) (or their employer(s)) 2022. To examine the effectiveness of integrated care intervention (ICI) models (stand-alone or combination of self-management, discharge management, case management and multidisciplinary teams models) targeting patients with one or more chronic conditions, and to identify outcome measures/indicators of effectiveness, we conducted a systematic review of published systematic reviews and meta-analyses. Included reviews comprise ICIs targeting adult patients with one or more long-term conditions. We searched MEDLINE, CINAHL and the Cochrane Database of Systematic Reviews: 60 reviews were included in the final analysis; 28 reviews evaluated ICIs focused on self-management, 4 on case management, 10 on discharge management and 5 on multidisciplinary teams; 13 reviews assessed multiple interventions that were labelled as complex. Across all reviews, only 19 reviews included intervention with multiple ICIs. Overall, interventions with multiple components, compared with interventions with single components, were more likely to improve hospital use outcomes effectively. Clinical/lifestyle/condition-specific outcomes were more likely to be improved by self-management interventions. Outcome measures identified could be classified into three main categories: organisational, patient-centred and clinical/lifestyle/condition-specific. The findings of this review may provide inputs to future design and evaluation of ICIs.Supplemental material: This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer- reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise
Structural evolution and magnetic properties of Gd2Hf2O7 nanocrystals: Computational and experimental investigations
Structural evolution in functional materials is a physicochemical phenomenon, which is important from a fundamental study point of view and for its applications in magnetism, catalysis, and nuclear waste immobilization. In this study, we used x-ray diffraction and Raman spectroscopy to examine the Gd2Hf2O7 (GHO) pyrochlore, and we showed that it underwent a thermally induced crystalline phase evolution. Superconducting quantum interference device measurements were carried out on both the weakly ordered pyrochlore and the fully ordered phases. These measurements suggest a weak magnetism for both pyrochlore phases. Spin density calculations showed that the Gd3+ ion has a major contribution to the fully ordered pyrochlore magnetic behavior and its cation antisite. The origin of the Gd magnetism is due to the concomitant shift of its spin-up 4f orbital states above the Fermi energy and its spin-down states below the Fermi energy. This picture is in contrast to the familiar Stoner model used in magnetism. The ordered pyrochlore GHO is antiferromagnetic, whereas its antisite is ferromagnetic. The localization of the Gd-4f orbitals is also indicative of weak magnetism. Chemical bonding was analyzed via overlap population calculations: These analyses indicate that Hf-Gd and Gd-O covalent interactions are destabilizing, and thus, the stabilities of these bonds are due to ionic interactions. Our combined experimental and computational analyses on the technologically important pyrochlore materials provide a basic understanding of their structure, bonding properties, and magnetic behaviors
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