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1.
Nat Commun ; 15(1): 3245, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622148

RESUMO

Information security and computing, two critical technological challenges for post-digital computation, pose opposing requirements - security (encryption) requires a source of unpredictability, while computing generally requires predictability. Each of these contrasting requirements presently necessitates distinct conventional Si-based hardware units with power-hungry overheads. This work demonstrates Cu0.3Te0.7/HfO2 ('CuTeHO') ion-migration-driven memristors that satisfy the contrasting requirements. Under specific operating biases, CuTeHO memristors generate truly random and physically unclonable functions, while under other biases, they perform universal Boolean logic. Using these computing primitives, this work experimentally demonstrates a single system that performs cryptographic key generation, universal Boolean logic operations, and encryption/decryption. Circuit-based calculations reveal the energy and latency advantages of the CuTeHO memristors in these operations. This work illustrates the functional flexibility of memristors in implementing operations with varying component-level requirements.

2.
World Neurosurg X ; 23: 100338, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38497061

RESUMO

Objective: Osteoporosis is a common skeletal disease that greatly increases the risk of pathologic fractures and accounts for approximately 700,000 vertebral compression fractures (VCFs) annually in the United States. Cement augmentation procedures such as balloon kyphoplasty (KP) and percutaneous vertebroplasty (VP) have demonstrated efficacy in the treatment of VCFs, however, some studies report rates of readmission as high as 10.8% following such procedures. The purpose of this study was to employ Machine Learning (ML) algorithms to predict 30-day hospital readmission following cement augmentation procedures for the treatment of VCFs using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Methods: ACS-NSQIP was queried to identify patients undergoing either KP or VP from 2011 to 2014. Three ML algorithms were constructed and tasked with predicting post-operative readmissions within this cohort of patients. Results: Postoperative pneumonia, ASA Class 2 designation, age, partially-dependent functional status, and a history of smoking were independently identified as highly predictive of readmission by all ML algorithms. Among these variables postoperative pneumonia (p < 0.01), ASA Class 2 designation (p < 0.01), age (p = 0.002), and partially-dependent functional status (p < 0.01) were found to be statistically significant. Predictions were generated with an average AUC value of 0.757 and an average accuracy of 80.5%. Conclusions: Postoperative pneumonia, ASA Class 2 designation, partially-dependent functional status, and age are perioperative variables associated with 30-day readmission following cement augmentation procedures. The use of ML allows for quantification of the relative contributions of these variables toward producing readmission.

3.
Environ Pollut ; 336: 122480, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37657722

RESUMO

Electronic cigarette (ECIG) use continues to be highly prevalent, especially among youth and young adults. Potential exposure from secondhand ECIG particulate matter (PM) places bystanders in danger of inhaling harmful substances, especially in confined spaces. This study was conducted to measure the potential exposure from secondhand ECIG PM exposure in vehicles, with participants completing a 30-min ECIG use session in their own vehicle with their preferred ECIG device. Sessions included a 5-min, 10-puff directed bout (30-s interpuff interval), followed by a 25-min ad libitum bout in which participants could take as many puffs as desired. Real-time PM1, PM2.5, and PM10 (the 50% efficiency mass cut-off of that passes through a size-selective inlet at 1 µm, 2.5 µm, and 10 µm aerodynamic diameters, respectively) measurements were captured during the sessions using portable PM monitors (MiniWRAS, pDR, SidePak, and GeoAir2 low-cost monitors). A total of 56 participants with valid measurements were included in the study, with a total of 13 unique ECIG device brands, including Vuse Alto, Box Air Bar, ElfBar, Esco Bar, Aegis Legend, Hyde Edge, JUUL, Kang Onee Stick, Kang Onee Stick Plus, Nord X, Nord 2, Nord 3, and Vaporesso. During the 5-min directed bout, the highest real-time PM2.5 mean concentrations were 175 µg/m3 for the MiniWRAS, 1050 µg/m3 for pDR and 3314 µg/m3 for SidePak. The filter measurements were not detectable in most experiments, except for two participants, with one taking 205 puffs and the other taking 285 puffs, approximately 10 times the mean (30) puffs of all participants. The evaluation of GeoAir2 with the MiniWRAS showed a wide range of Pearson correlation coefficient (r) values, ranging from -0.03 to 1.00, for the 13 ECIG brands. The mass median diameter (0.31 µm-3.42 µm) and geometric standard deviation (2.47-8.21) were different based on the participants for the same ECIG brand.


Assuntos
Poluentes Atmosféricos , Sistemas Eletrônicos de Liberação de Nicotina , Adolescente , Adulto Jovem , Humanos , Material Particulado/análise , Nicotina , Poluentes Atmosféricos/análise
4.
Drug Alcohol Depend ; 250: 110889, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37478503

RESUMO

BACKGROUND: Electronic cigarette (ECIG) use in vehicles represents a public health concern due to the potential for exposure to high concentrations of particulate matter (PM) and other toxicants. This study examined the impact of ECIG use on air quality in vehicles. METHODS: People who reported current ECIG use (n=60; mean age=20.5, SD=2.3) completed a brief survey and a 30-min ECIG use session in their own vehicle. Using a protocol similar to clinical laboratory studies involving tobacco use, participants took 10 directed puffs (i.e., a directed bout with one puff every 30s for 5min) followed by a 25-min ad libitum period in which participants took as many puffs as desired. PM 2.5µm in diameter or smaller (PM2.5) were measured using aerosol monitors set up to sample air from the breathing zone of the passenger seat and total puffs were recorded. The association between peak PM2.5 concentration and puff count was examined. RESULTS: Participants took a median 18 total puffs during the sessions. Median PM2.5 concentrations increased from 4.78µg/m3 at baseline to 107.40µg/m3 after the directed bout. Median peak PM2.5 concentration was 464.48µg/m3 and ranged from 9.56µg/m3 to 143,503.91µg/m3 (IQR=132.72-1604.68). After removing two extreme outliers for puff count and PM2.5 concentrations, puff count was significantly correlated with peak PM2.5 concentration during the ad libitum bout (r=0.32, p=0.015). CONCLUSIONS: ECIG use in vehicles impacts air quality negatively and may pose health risks to those present in vehicles when ECIG use is occurring.


Assuntos
Poluição do Ar em Ambientes Fechados , Sistemas Eletrônicos de Liberação de Nicotina , Humanos , Adulto Jovem , Adulto , Nicotina , Fumar , Poluição do Ar em Ambientes Fechados/análise , Aerossóis , Material Particulado
5.
J Bone Joint Surg Am ; 105(19): 1512-1518, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37471568

RESUMO

BACKGROUND: Although the radiographic parameters for diagnosing central lumbar canal stenosis are well described, parameters for the diagnosis of neuroforaminal stenosis (NFS) are less well defined. Previous studies have used magnetic resonance imaging (MRI) and radiography to describe neuroforaminal dimensions (NFDs). Those methods, however, have limitations that may substantially distort measurements. Existing literature on the use of computed tomography (CT) to investigate normal NFDs is limited. METHODS: This anatomic assessment evaluated CT imaging of 300 female and 300 male subjects between 18 and 35 years of age to determine normal NFDs, specifically the sagittal anteroposterior width, axial anteroposterior width, craniocaudal height, and area. Statistical analyses were performed to assess differences in NFDs according to variables including sex, age, height, weight, body mass index, and ethnicity. RESULTS: Overall, mean NFDs were 9.08 mm for sagittal anteroposterior width, 8.93 mm for axial anteroposterior width, 17.46 mm for craniocaudal height, and 134.78 mm 2 for area (n = 6,000 measurements each). Male subjects had larger NFDs than females at multiple levels. Both Caucasian and Asian subjects had larger NFDs than African-American subjects at multiple levels. There were no associations between foraminal dimensions and anthropometric factors. CONCLUSIONS: This study describes CT-based L1-S1 NFDs in young, healthy patients who presented with reasons other than back pain or pathology affecting the neuroforamen. Dimensions were influenced by sex and ethnicity but were not influenced by anthropometric factors. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

6.
Phys Ther Sport ; 62: 32-38, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37300971

RESUMO

OBJECTIVES: Lateral ankle sprains involving the ATFL and CFL are common injuries in football with a high recurrence rate. There is a lack of research to guide post-operative rehabilitation of football players following lateral ligament ankle reconstructive surgery. This narrative case report discusses the management of a lateral ligament reconstruction in a male professional football player. METHODS: A 25-year-old professional footballer underwent a lateral ankle reconstruction following recurrent lateral ankle sprains leading to an unstable ankle. RESULTS: Following 11-weeks of rehabilitation the player was cleared to return to full-contact training. The player competed in his first competitive match 13-weeks post-injury and completed a 6-month full-training block, without episodes of pain or instability. CONCLUSION: This case report illustrates the rehabilitation process of a football player following a lateral ankle ligament reconstruction within a timeframe expected in elite sport.


Assuntos
Traumatismos do Tornozelo , Futebol Americano , Humanos , Masculino , Adulto , Futebol Americano/lesões , Tornozelo , Articulação do Tornozelo/cirurgia , Traumatismos do Tornozelo/cirurgia
7.
bioRxiv ; 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37205496

RESUMO

Ischemic stroke results in a loss of tissue homeostasis and integrity, the underlying pathobiology of which stems primarily from the depletion of cellular energy stores and perturbation of available metabolites 1 . Hibernation in thirteen-lined ground squirrels (TLGS), Ictidomys tridecemlineatus , provides a natural model of ischemic tolerance as these mammals undergo prolonged periods of critically low cerebral blood flow without evidence of central nervous system (CNS) damage 2 . Studying the complex interplay of genes and metabolites that unfolds during hibernation may provide novel insights into key regulators of cellular homeostasis during brain ischemia. Herein, we interrogated the molecular profiles of TLGS brains at different time points within the hibernation cycle via RNA sequencing coupled with untargeted metabolomics. We demonstrate that hibernation in TLGS leads to major changes in the expression of genes involved in oxidative phosphorylation and this is correlated with an accumulation of the tricarboxylic acid (TCA) cycle intermediates citrate, cis-aconitate, and α-ketoglutarate-αKG. Integration of the gene expression and metabolomics datasets led to the identification of succinate dehydrogenase (SDH) as the critical enzyme during hibernation, uncovering a break in the TCA cycle at that level. Accordingly, the SDH inhibitor dimethyl malonate (DMM) was able to rescue the effects of hypoxia on human neuronal cells in vitro and in mice subjected to permanent ischemic stroke in vivo . Our findings indicate that studying the regulation of the controlled metabolic depression that occurs in hibernating mammals may lead to novel therapeutic approaches capable of increasing ischemic tolerance in the CNS.

8.
Pharmacoecon Open ; 7(3): 417-429, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37041324

RESUMO

INTRODUCTION: Effective preparation of children for hospital procedures, including non-sedated medical imaging, is an important clinical issue. This study aimed to assess the costs and consequences (effects) of preparing pediatric patients using two methods of delivering preparation for a scheduled magnetic resonance image (MRI)-virtual reality (VR-MRI) and a certified Child Life Program (CLP). METHODS: A cost-consequence analysis (CCA) was performed using a societal perspective in Canada. The CCA catalogs a wide range of costs and consequences of VR-MRI compared with a CLP. The evaluation uses data from a prior randomized clinical trial evaluating VR and a CLP in a simulated trial. The economic evaluation encompassed health-related effects, including anxiety, safety and adverse events, and non-health effects, including preparation time, displaced time from usual activities, workload capacity, patient-specific adaptation, administrative burden, and user-experience metrics. The costs have been categorized into hospital operational costs, travel costs, other patient costs, and societal costs. RESULTS: VR-MRI has similar benefits to the CLP in managing anxiety, safety and adverse events, as well as converting patients to non-sedated medical imaging. Preparation time and patient-specific adaptation are in favor of the CLP, while displaced time from usual activities, potential workload capacity, and administrative burden are in favor of VR-MRI. Both programs rank favorably in terms of user experience. The hospital operational costs ranged in Canadian dollars (CAN$) from CAN$32.07 for the CLP to between CAN$107.37 and CAN$129.73 for VR-MRI. Travel costs ranged from CAN$50.58 to CAN$2365.18 depending on travel distance for the CLP, and CAN$0 for VR-MRI. Other patient costs involved caregiver time off, and ranged from CAN$190.69 to CAN$$1144.16 for the CLP and CAN$47.67 for VR-MRI. The total cost for the CLP ranged from CAN$315.16 (CAN$277.91-$426.64) to CAN$3843.41 (CAN$3196.59-$4849.91) per patient depending on travel distance and amount of administrative support required, while VR-MRI preparation ranged from CAN$178.30 (CAN$178.20-$188.76) to CAN$283.85 (CAN$283.71-$298.40) per patient. For every instance where patient travel to visit a Certified Child Life Specialist (CCLS) onsite was replaced with VR-MRI, between CAN$119.01 and CAN$3364.62 total costs could be saved per patient. CONCLUSIONS: While it is neither feasible nor appropriate to replace all preparation with VR, using VR to reach children who cannot otherwise visit the CLP onsite could increase access to quality preparation, and using VR in place of the CLP where clinically indicated could reduce the overall costs for patients, the hospital, and society. Our CCA gives decision makers a cost analysis and the relevant effects of each preparation program so they can value the VR and CLP programs more broadly within the potential health and non-health outcomes of pediatric patients scheduled for MRI at their facilities.

9.
Tob Control ; 31(Suppl 3): s197-s205, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36328459

RESUMO

BackgroundRegulations have been proposed to limit e-cigarette flavours, but limited research has examined potential impacts of such policies. This study examined adult e-cigarette users' reactions to a hypothetical e-cigarette flavour ban. METHODS: In 2019, a convenience sample of current e-cigarette users in the USA (n=81, 53.1% women, mean age=37.6, 59.3% dual users of cigarettes) completed an online concept mapping study. Participants provided statements describing anticipated reactions to a hypothetical policy in which only tobacco, menthol or unflavoured e-cigarettes were available for purchase. Seventy-one unique statements were generated. Participants sorted statements into thematic groups and rated statements on how likely they would be to have each reaction. Multidimensional scaling was used to identify thematic clusters of statements. RESULTS: Twelve clusters were identified: negative reaction, take action against flavour limitation, youth prevention effectiveness perception, tolerance, acceptance, willingness to try new flavours, maintain vaping, reduce vaping, new flavours as vaping cessation transition, alternative sources for banned flavours, do-it-yourself mixing behaviours and alternative tobacco products. The highest rated cluster (negative reaction) described being angry or upset that flavours were banned, while the lowest rated clusters related to quitting/reducing e-cigarette use or switching to other tobacco products. Non-tobacco or non-menthol/mint flavoured e-cigarette users had higher ratings for clusters describing negative sentiment for the hypothetical policy. CONCLUSIONS: Some e-cigarette users may dislike an e-cigarette flavour ban; however, some e-cigarette users would likely be willing to use tobacco, menthol or unflavoured e-cigarette liquids with lower likelihood of quitting vaping or switching to other tobacco products.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Adulto , Adolescente , Feminino , Humanos , Masculino , Aromatizantes , Fumantes , Mentol
10.
Mol Biol Evol ; 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36219871

RESUMO

Climate change threatens the survival of coral reefs on a global scale, primarily through mass bleaching and mortality as a result of marine heatwaves. While these short-term effects are clear, predicting the fate of coral reefs over the coming century is a major challenge. One way to understand the longer-term effects of rapid climate change is to examine the response of coral populations to past climate shifts. Coastal and shallow-water marine ecosystems such as coral reefs have been reshaped many times by sea-level changes during the Pleistocene, yet, few studies have directly linked this with its consequences on population demographics, dispersal, and adaptation. Here we use powerful analytical techniques, afforded by haplotype phased whole-genomes, to establish such links for the reef-building coral, Acropora digitifera. We show that three genetically distinct populations are present in northwestern Australia, and that their rapid divergence since the last glacial maximum (LGM) can be explained by a combination of founder-effects and restricted gene flow. Signatures of selective sweeps, too strong to be explained by demographic history, are present in all three populations and overlap with genes that show different patterns of functional enrichment between inshore and offshore habitats. In contrast to rapid divergence in the host, we find that photosymbiont communities are largely undifferentiated between corals from all three locations, spanning almost 1000 km, indicating that selection on host genes and not acquisition of novel symbionts, has been the primary driver of adaptation for this species in northwestern Australia.

11.
Faraday Discuss ; 239(0): 250-262, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35848780

RESUMO

Germanium selenide (GeSe) bulk crystals, thin films and solar cells are investigated with a focus on acceptor-doping with silver (Ag) and the use of an Sb2Se3 interfacial layer. The Ag-doping of GeSe occurred by a stoichiometric melt growth technique that created Ag-doped GeSe bulk crystals. A combination of capacitance voltage measurements, synchrotron radiation photoemission spectroscopy and surface space-charge calculations indicates that Ag-doping increases the hole density from 5.2 × 1015 cm-3 to 1.9 × 1016 cm-3. The melt-grown material is used as the source for thermally evaporated GeSe films within solar cells. The cell structure with the highest efficiency of 0.260% is FTO/CdS/Sb2Se3/undoped-GeSe/Au, compared with solar cells without the Sb2Se3 interfacial layer or with the Ag-doped GeSe.

12.
PeerJ ; 10: e13323, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669950

RESUMO

An understanding of stock recruitment dynamics in fisheries is fundamental to successful management. Pinctada maxima is a bivalve mollusc widely distributed throughout the Indo-Pacific and is the main species targeted for cultured pearl and pearl shell production in Australia. Pearl production in Australia relies heavily on wild-caught individuals, the majority of which come from the Eighty Mile Beach region near Broome in Western Australia. In this study, we used a genotyping by sequencing approach to explore fine-scale patterns of genetic connectivity among inshore shallow and offshore deep populations of P. maxima near Eighty Mile Beach. Our results revealed high-levels of gene flow among inshore and offshore sites and no differences in genetic diversity between depths. Global estimates of genetic differentiation were low (F ST = 0.006) but significantly different from zero, and pairwise estimates of genetic differentiation among sites were significant in only 3% of comparisons. Moreover, Bayesian clustering detected no separation of inshore and offshore sample sites, and instead showed all samples to be admixed among sites, locations and depths. Despite an absence of any clear spatial clustering among sites, we identified a significant pattern of isolation by distance. In a dynamic environment like Eighty Mile Beach, genetic structure can change from year-to-year and successive dispersal and recruitment events over generations likely act to homogenize the population. Although we cannot rule out the null hypothesis of panmixia, our data indicate high levels of dispersal and connectivity among inshore and offshore fishing grounds.


Assuntos
Pinctada , Humanos , Animais , Pinctada/genética , Fluxo Gênico , Austrália Ocidental , Teorema de Bayes , Pesqueiros
13.
Mol Ecol ; 31(13): 3533-3547, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35567512

RESUMO

Anthropogenic climate change has caused widespread loss of species biodiversity and ecosystem productivity across the globe, particularly on tropical coral reefs. Predicting the future vulnerability of reef-building corals, the foundation species of coral reef ecosystems, is crucial for cost-effective conservation planning in the Anthropocene. In this study, we combine regional population genetic connectivity and seascape analyses to explore patterns of genetic offset (the mismatch of gene-environmental associations under future climate conditions) in Acropora digitifera across 12 degrees of latitude in Western Australia. Our data revealed a pattern of restricted gene flow and limited genetic connectivity among geographically distant reef systems. Environmental association analyses identified a suite of loci strongly associated with the regional temperature variation. These loci helped forecast future genetic offset in gradient forest and generalized dissimilarity models. These analyses predicted pronounced differences in the response of different reef systems in Western Australia to rising temperatures. Under the most optimistic future warming scenario (RCP 2.6), we predicted a general pattern of increasing genetic offset with latitude. Under the extreme climate scenario (RCP 8.5 in 2090-2100), coral populations at the Ningaloo World Heritage Area were predicted to experience a higher mismatch between current allele frequencies and those required to cope with local environmental change, compared to populations in the inshore Kimberley region. The study suggests complex and spatially heterogeneous patterns of climate-change vulnerability in coral populations across Western Australia, reinforcing the notion that regionally tailored conservation efforts will be most effective at managing coral reef resilience into the future.


Assuntos
Antozoários , Animais , Antozoários/genética , Mudança Climática , Recifes de Corais , Ecossistema , Fluxo Gênico , Austrália Ocidental
14.
Br Dent J ; 232(8): 556-567, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35459832

RESUMO

Introduction 'Preparedness for practice' refers to a multifaceted concept, encompassing not only clinical skills, but also broader, non-clinical skills, such as communication and professionalism. Previous graduates have reported feeling less prepared for complex procedures, such as molar endodontics and surgical extractions. Dental students typically utilise their final year to refine their clinical skills, however, the COVID-19 pandemic has meant that newly qualified dentists will have had around six months where they have not performed clinical dentistry before beginning dental foundation training (DFT).Aims This study aimed to explore final year students' self-reported preparedness for practice, identify areas of relative weakness that may influence future training needs and to highlight any perceived impact of the pandemic on final year experience and potential impact on DFT.Materials and methods The current Graduate Assessment of Preparedness for Practice (GAPP) questionnaire was adapted for our specific research aims and piloted and the PreGAPP questionnaire distributed via the social media channels of dental school student societies. Analysis was carried out using IBM Statistical Package for the Social Sciences software using descriptive statistics and the Mann-Whitney U test for two unrelated variables.Results Responses were received from final year students across all 16 UK dental schools. Students reported increased preparedness across domains in which they had the most experience; for example, providing preventative advice and administering local anaesthesia. Male students reported feeling significantly more prepared than female students, mature students significantly more than younger students, and students on four-year courses significantly more than traditional five-year courses. The COVID-19 pandemic was expected to have a major-to-severe impact on undergraduate experience and future DFT prospects.Conclusion Dental graduates in the COVID-19 era may have significantly different training needs to those before them. Complex clinical procedures remain the areas where students feel they are least prepared for practice. The importance of a clinical passport to highlight current experience level to trainers, alongside the creation of a personal development plan at the beginning of DFT, will ensure that targeted and personalised training can be implemented where required.


Assuntos
COVID-19 , Pandemias , COVID-19/epidemiologia , COVID-19/prevenção & controle , Competência Clínica , Atenção à Saúde , Feminino , Humanos , Masculino , Inquéritos e Questionários
15.
Sci Adv ; 8(17): eabl9185, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35476443

RESUMO

At the Rowley Shoals in Western Australia, the prominent reef flat becomes exposed on low tide and the stagnant water in the shallow atoll lagoons heats up, creating a natural laboratory for characterizing the mechanisms of coral resilience to climate change. To explore these mechanisms in the reef coral Acropora tenuis, we collected samples from lagoon and reef slope habitats and combined whole-genome sequencing, ITS2 metabarcoding, experimental heat stress, and transcriptomics. Despite high gene flow across the atoll, we identified clear shifts in allele frequencies between habitats at relatively small linked genomic islands. Common garden heat stress assays showed corals from the lagoon to be more resistant to bleaching, and RNA sequencing revealed marked differences in baseline levels of gene expression between habitats. Our results provide new insight into the complex mechanisms of coral resilience to climate change and highlight the potential for spatially varying selection across complex coral reef seascapes to drive pronounced ecological divergence in climate-related traits.

16.
J Health Polit Policy Law ; 47(4): 473-496, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35044461

RESUMO

CONTEXT: Previous studies show that nonprofit hospital spending on charity care declined in Medicaid expansion states. We test whether state community benefit regulations mitigated the decline in charity care spending. METHODS: We use a fixed effects model to evaluate the association between state regulations and nonprofit hospital community benefit spending and its subcategories as a share of total expenses in Medicaid expansion states. We obtained community benefit spending data from the Internal Revenue Service Form 990 Schedule H filings of 1,738 hospitals in 44 states and the District of Columbia from 2010 to 2017. We determine the stringency of state regulations by comparing the provisions of state and federal requirements based on regulation information compiled by the Hilltop Institute. FINDINGS: State minimum community benefit requirements are associated with increased community benefit and charity care spending by nonprofit hospitals in Medicaid expansion states. CONCLUSIONS: States that imposed minimum community benefit requirements on nonprofit hospitals did not experience a decline in charity care spending after Medicaid expansion. The results suggest state minimum community benefit rules may expand the provision of community benefit and charitable care spending.


Assuntos
Medicaid , Cuidados de Saúde não Remunerados , Hospitais , Humanos , Organizações sem Fins Lucrativos , Estados Unidos
17.
Ecol Appl ; 32(3): e2548, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35094450

RESUMO

The decline of biodiversity from anthropogenic landscape modification is among the most pressing conservation problems worldwide. In North America, long-term population declines have elevated the recovery of the grassland avifauna to among the highest conservationpriorities. Because the vast majority of grasslands of the Great Plains are privately owned, the recovery of these ecosystems and bird populations within them depend on landscape-scale conservation strategies that integrate social, economic, and biodiversity objectives. The Conservation Reserve Program (CRP) is a voluntary program for private agricultural producers administered by the United States Department of Agriculture that provides financial incentives to take cropland out of production and restore perennial grassland. We investigated spatial patterns of grassland availability and restoration to inform landscape-scale conservation for a comprehensive community of grassland birds in the Great Plains. The research objectives were to (1) determine how apparent habitat loss has affected spatial patterns of grassland bird biodiversity, (2) evaluate the effectiveness of CRP for offsetting the biodiversity declines of grassland birds, and (3) develop spatially explicit predictions to estimate the biodiversity benefit of adding CRP to landscapes impacted by habitat loss. We used the Integrated Monitoring in Bird Conservation Regions program to evaluate hypotheses for the effects of habitat loss and restoration on both the occupancy and species richness of grassland specialists within a continuum-modeling framework. We found the odds of community occupancy declined by 37% for every 1 SD decrease in grassland availability [loge (km2 )] and increased by 20% for every 1 SD increase in CRP land cover [loge (km2 )]. There was 17% turnover in species composition between intact grasslands and CRP landscapes, suggesting that grasslands restored by CRP retained considerable, but incomplete, representation of biodiversity in agricultural landscapes. Spatially explicit predictions indicated that absolute conservation outcomes were greatest at high latitudes in regions with high biodiversity, whereas the relative outcomes were greater at low latitudes in highly modified landscapes. By evaluating community-wide responses to landscape modification and CRP restoration at bioregional scales, our study fills key information gaps for developing collaborative strategies, and for balancing conservation of avian biodiversity and social well-being in the agricultural production landscapes of the Great Plains.


Assuntos
Ecossistema , Pradaria , Animais , Biodiversidade , Aves/fisiologia , Conservação dos Recursos Naturais , Dinâmica Populacional
18.
Mol Ecol Resour ; 22(1): 56-65, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34146448

RESUMO

Population genetic data can provide valuable information on the demography of a species. For rare and elusive marine megafauna, samples for generating the data are traditionally obtained from tissue biopsies, which can be logistically difficult and expensive to collect and require invasive sampling techniques. Analysis of environmental DNA (eDNA) offers an alternative, minimally invasive approach to provide important genetic information. Although eDNA approaches have been studied extensively for species detection and biodiversity monitoring in metabarcoding studies, the potential for the technique to address population-level questions remains largely unexplored. Here, we applied "eDNA haplotyping" to obtain estimates of the intraspecific genetic diversity of a whale shark (Rhincodon typus) aggregation at Ningaloo reef, Australia. Over 2 weeks, we collected seawater samples directly behind individual sharks prior to taking a tissue biopsy sample from the same animal. Our data showed a 100% match between mtDNA sequences recovered in the eDNA and tissue sample for all 28 individuals sampled. In the seawater samples, >97% of all reads were assigned to six dominant haplotypes, and a clear dominant signal (~99% of sample reads) was recovered in each sample. Our study demonstrates accurate individual-level haplotyping from seawater eDNA. When DNA from one individual clearly dominates each eDNA sample, it provides many of the same opportunities for population genetic analyses as a tissue sample, potentially removing the need for tissue sampling. Our results show that eDNA approaches for population-level analyses have the potential to supply critical demographic data for the conservation and management of marine megafauna.


Assuntos
DNA Ambiental , Tubarões , Animais , Austrália , Haplótipos , Água do Mar , Tubarões/genética
19.
BMC Biol ; 19(1): 265, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911556

RESUMO

BACKGROUND: Tissue hypoxia is a key feature of several endemic hepatic diseases, including alcoholic and non-alcoholic fatty liver disease, and organ failure. Hypoxia imposes a severe metabolic challenge on the liver, potentially disrupting its capacity to carry out essential functions including fuel storage and the integration of lipid metabolism at the whole-body level. Mitochondrial respiratory function is understood to be critical in mediating the hepatic hypoxic response, yet the time-dependent nature of this response and the role of the respiratory chain in this remain unclear. RESULTS: Here, we report that hepatic respiratory capacity is enhanced following short-term exposure to hypoxia (2 days, 10% O2) and is associated with increased abundance of the respiratory chain supercomplex III2+IV and increased cardiolipin levels. Suppression of this enhanced respiratory capacity, achieved via mild inhibition of mitochondrial complex III, disrupted metabolic homeostasis. Hypoxic exposure for 2 days led to accumulation of plasma and hepatic long chain acyl-carnitines. This was observed alongside depletion of hepatic triacylglycerol species with total chain lengths of 39-53 carbons, containing palmitic, palmitoleic, stearic, and oleic acids, which are associated with de novo lipogenesis. The changes to hepatic respiratory capacity and lipid metabolism following 2 days hypoxic exposure were transient, becoming resolved after 14 days in line with systemic acclimation to hypoxia and elevated circulating haemoglobin concentrations. CONCLUSIONS: The liver maintains metabolic homeostasis in response to shorter term hypoxic exposure through transient enhancement of respiratory chain capacity and alterations to lipid metabolism. These findings may have implications in understanding and treating hepatic pathologies associated with hypoxia.


Assuntos
Metabolismo dos Lipídeos , Fígado , Homeostase , Humanos , Hipóxia/metabolismo , Lipogênese , Fígado/metabolismo
20.
Front Cell Dev Biol ; 9: 695351, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746119

RESUMO

Mitochondria are key organelles in eukaryotic evolution that perform crucial roles as metabolic and cellular signaling hubs. Mitochondrial function and dysfunction are associated with a range of diseases, including cancer. Mitochondria support cancer cell proliferation through biosynthetic reactions and their role in signaling, and can also promote tumorigenesis via processes such as the production of reactive oxygen species (ROS). The advent of (nuclear) genome-wide CRISPR-Cas9 deletion screens has provided gene-level resolution of the requirement of nuclear-encoded mitochondrial genes (NEMGs) for cancer cell viability (essentiality). More recently, it has become apparent that the essentiality of NEMGs is highly dependent on the cancer cell context. In particular, key tumor microenvironmental factors such as hypoxia, and changes in nutrient (e.g., glucose) availability, significantly influence the essentiality of NEMGs. In this mini-review we will discuss recent advances in our understanding of the contribution of NEMGs to cancer from CRISPR-Cas9 deletion screens, and discuss emerging concepts surrounding the context-dependent nature of mitochondrial gene essentiality.

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