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1.
Clin Chem ; 70(5): 759-767, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38484302

RESUMO

BACKGROUND: Identification of tumor-derived variants in circulating tumor DNA (ctDNA) has potential as a sensitive and reliable surrogate for tumor tissue-based routine diagnostic testing. However, variations in pre(analytical) procedures affect the efficiency of ctDNA recovery. Here, an external quality assessment (EQA) was performed to determine the performance of ctDNA mutation detection work flows that are used in current diagnostic settings across laboratories within the Dutch COIN consortium (ctDNA on the road to implementation in The Netherlands). METHODS: Aliquots of 3 high-volume diagnostic leukapheresis (DLA) plasma samples and 3 artificial reference plasma samples with predetermined mutations were distributed among 16 Dutch laboratories. Participating laboratories were requested to perform ctDNA analysis for BRAF exon 15, EGFR exon 18-21, and KRAS exon 2-3 using their regular circulating cell-free DNA (ccfDNA) analysis work flow. Laboratories were assessed based on adherence to the study protocol, overall detection rate, and overall genotyping performance. RESULTS: A broad range of preanalytical conditions (e.g., plasma volume, elution volume, and extraction methods) and analytical methodologies (e.g., droplet digital PCR [ddPCR], small-panel PCR assays, and next-generation sequencing [NGS]) were used. Six laboratories (38%) had a performance score of >0.90; all other laboratories scored between 0.26 and 0.80. Although 13 laboratories (81%) reached a 100% overall detection rate, the therapeutically relevant EGFR p.(S752_I759del) (69%), EGFR p.(N771_H773dup) (50%), and KRAS p.(G12C) (48%) mutations were frequently not genotyped accurately. CONCLUSIONS: Divergent (pre)analytical protocols could lead to discrepant clinical outcomes when using the same plasma samples. Standardization of (pre)analytical work flows can facilitate the implementation of reproducible liquid biopsy testing in the clinical routine.


Assuntos
DNA Tumoral Circulante , Humanos , DNA Tumoral Circulante/sangue , DNA Tumoral Circulante/genética , Mutação , Neoplasias/genética , Neoplasias/sangue , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptores ErbB/genética , Receptores ErbB/sangue , Proteínas Proto-Oncogênicas B-raf/genética , Países Baixos
2.
J Magn Reson Imaging ; 59(1): 223-230, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37144669

RESUMO

BACKGROUND: Different Circle of Willis (CoW) variants have variable prevalences of aneurysm development, but the hemodynamic variation along the CoW and its relation to presence and size of unruptured intracranial aneurysms (UIAs) are not well known. PURPOSE: Gain insight into hemodynamic imaging markers of the CoW for UIA development by comparing these outcomes to the corresponding contralateral artery without an UIA using 4D flow magnetic resonance imaging (MRI). STUDY TYPE: Retrospective, cross-sectional study. SUBJECTS: Thirty-eight patients with an UIA, whereby 27 were women and a mean age of 62 years old. FIELD STRENGTH/SEQUENCE: Four-dimensional phase-contrast (PC) MRI with a 3D time-resolved velocity encoded gradient echo sequence at 7 T. ASSESSMENT: Hemodynamic parameters (blood flow, velocity pulsatility index [vPI], mean velocity, distensibility, and wall shear stress [peak systolic (WSSMAX ), and time-averaged (WSSMEAN )]) in the parent artery of the UIA were compared to the corresponding contralateral artery without an UIA and were related to UIA size. STATISTICAL TESTS: Paired t-tests and Pearson Correlation tests. The threshold for statistical significance was P < 0.05 (two-tailed). RESULTS: Blood flow, mean velocity, WSSMAX , and WSSMEAN were significantly higher, while vPI was lower, in the parent artery relative to contralateral artery. The WSSMAX of the parent artery significantly increased linearly while the WSSMEAN decreased linearly with increasing UIA size. CONCLUSIONS: Hemodynamic parameters and WSS differ between parent vessels of UIAs and corresponding contralateral vessels. WSS correlates with UIA size, supporting a potential hemodynamic role in aneurysm pathology. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Aneurisma Intracraniano , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Aneurisma Intracraniano/diagnóstico por imagem , Estudos Retrospectivos , Estudos Transversais , Imageamento por Ressonância Magnética , Hemodinâmica/fisiologia , Artérias
3.
Conserv Biol ; : e14375, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225272

RESUMO

Biodiversity is confronted globally by multiple stressors. Environmental policies must regulate these stressors to achieve targets, but how should that be done when the outcomes of limits on one stressor are contingent on other stressors, about which there is imperfect knowledge? Deriving regulatory frameworks that incorporate these contingencies is an emerging challenge at the science-policy interface. To be fit for implementation, these frameworks need to facilitate the inherently sociopolitical process of policy implementation and account transparently for uncertainty, such that practitioners and other stakeholders can more realistically anticipate the range of potential outcomes to policy. We developed an approach to quantify stressor limits that explicitly accounts for multistressor contingencies. Using an invertebrate data set collected over 30 years throughout New Zealand, we combined ecological and ecotoxicological models to predict biodiversity loss as a function of one stressor, treating multistressor contingencies as a form of uncertainty about the outcomes of limits on that stressor. We transparently accounted for that uncertainty by presenting regulatory limits as bands bounded between optimistic and pessimistic views that practitioners may have about the local context within which limits are applied. In addition to transparently accounting for uncertainties, our framework also leaves room for practitioners to build stakeholder consensus when refining limits to suit different local contexts. A criticism of this open, transparent approach is that it creates too much scope for choosing limits that are lenient on polluters, paralyzing on-the-ground management of multiple stressors, but we demonstrate that this is not necessarily the case.


Cuantificación abierta y transparente de los límites regulatorios para varios estresantes Resumen La biodiversidad enfrenta a múltiples estresantes en todo el mundo. Las políticas ambientales deben regularlos para alcanzar los objetivos fijados, pero ¿cómo hacerlo cuando los resultados de la limitación de un estresante dependen de otros factores, de los que se conoce muy poco? La elaboración de marcos reguladores que incorporen estas contingencias es un reto emergente en la interfaz ciencia­política. Para aplicar estos marcos, se debe facilitar el proceso sociopolítico inherente a la aplicación de políticas y tener en cuenta de forma transparente la incertidumbre, de modo que los profesionales y otras partes interesadas puedan anticipar de forma más realista la variedad de posibles resultados de las políticas. Desarrollamos un método para cuantificar los límites de los estresantes que considera explícitamente las contingencias de múltiples factores. Usamos un conjunto de datos sobre invertebrados recolectados durante 30 años en toda Nueva Zelanda. Después combinamos modelos ecológicos y eco­toxicológicos para predecir la pérdida de biodiversidad en función de un estresante y tratamos las contingencias de múltiples estresantes como una forma de incertidumbre sobre los resultados de los límites de ese mismo estresante. Explicamos esa incertidumbre de forma transparente con los límites normativos como bandas delimitadas entre las opiniones optimistas y pesimistas que los profesionales pueden tener sobre el contexto local en el que se aplican los límites. Además de hacer lo anterior, nuestro marco también deja margen para que los profesionales lleguen a un consenso con las partes interesadas a la hora de perfeccionar los límites para adaptarlos a los distintos contextos locales. Una crítica a este enfoque abierto y transparente crea demasiado margen para elegir límites indulgentes con los contaminadores, paralizando la gestión sobre el terreno de múltiples estresantes, pero demostramos que no es necesariamente así.

4.
J Arthroplasty ; 39(3): 750-753, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37640246

RESUMO

BACKGROUND: Femoral neck retaining prostheses have gained popularity in Europe, but the United States has not seen the same trends occurring. Previous reports demonstrate high survivorship for these implants, but to our knowledge, there are no reports examining US data. METHODS: After institutional review board approval, 824 primary total hip arthroplasties utilizing a femoral neck-retaining prosthesis were examined for femoral component survivorship rates. European studies were systematically reviewed to determine survivorship rates. The data were used to formulate a Kaplan-Meier survivorship curve and compare US data to that of the European studies. RESULTS: European studies demonstrated survivorship rates for all causes of 97.7 and 99.0% for aseptic loosening at an average of 6 years (range, 4.5 to 10). The current study demonstrated an all-cause 94% Kaplan-Meier survivorship estimate at 5 years and when aseptic loosening only was considered, survivorship increased to 99.4% at 5 years and 98.4% at 11 years. CONCLUSION: This femoral neck-retaining prosthesis demonstrated excellent survivorship that is comparable to the rates seen in European studies as well as the rates of standard and mid-stem prostheses in the United States.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Humanos , Estados Unidos , Estudos Retrospectivos , Colo do Fêmur/cirurgia , Resultado do Tratamento , Fêmur/cirurgia , Desenho de Prótese , Falha de Prótese , Reoperação , Seguimentos
5.
J Environ Manage ; 351: 119787, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38081085

RESUMO

Monitoring for adaptive management (AM) involves collection of data with the aim of reducing uncertainty about links between human pressures (e.g. water abstraction from rivers), consequent stressors (e.g. low river flows) and environmental state (e.g. biodiversity). 'Surveillance monitoring' involves documenting trends in state, without the aim of understanding relationships between state, stressors, and pressures. Critics have highlighted that surveillance monitoring dominates monitoring investments but is not supporting AM. Decision-makers continue to be disappointed by monitoring data that are unsuitable for AM, yet designers of monitoring programs tend to make decisions that reinforce rather than reimagine the status quo. We argue that a structured, collaborative approach to objective-setting is required to break the status quo. We collaborated with regional management authorities to develop monitoring objectives and implementation strategies to support AM of New Zealand's rivers. Our collaborative approach discouraged 'failure fearing' and encouraged reimagining 'what could be' as opposed to 'what is.' Seventeen monitoring objectives were identified based on the AM requirements of national policy and regional authorities. Several objectives-particularly those arising from national policy-stretch the limits of what environmental science can currently provide. There were also strong trade-offs among objectives. We offer practical implementation strategies for overcoming the technical challenges of, and reducing trade-offs among, monitoring objectives. These strategies point to a monitoring program that contrasts strongly with one aimed at surveillance. Monitoring for AM is more complex than monitoring for surveillance, so strong leadership is required for successful implementation.


Assuntos
Ecossistema , Rios , Humanos , Monitoramento Ambiental , Biodiversidade , Incerteza
6.
J Hand Ther ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38490877

RESUMO

BACKGROUND: Spontaneous rupture of the extensor pollicis longus (EPL) tendon following both nonoperative and operative treatment of distal radius fractures has been well described. PURPOSE: The purpose of this study was to assess long-term outcomes of extensor indicis proprius to EPL tendon transfers for patients following distal radius fracture and EPL tendon repair. STUDY DESIGN: Retrospective case series focusing on long-term clinical outcomes. METHODS: A retrospective review was conducted for patients who sustained a distal radius fracture and subsequently underwent extensor tendon transfer from 2005-2015 at a private practice center. Outcome measures including index finger (IF) metacarpophalangeal (MCP) and thumb interphalangeal (IP) active range of motion (ROM), digital extension against resistance, subjective complaints, and QuickDASH scores were recorded at final follow-up. RESULTS: Seven patients were included in the study. There were six females and one male subject, mean age of 54 ± 13 years at injury of EPL, and 5/7 involved the left upper extremity. For isolated function, 7/7 (100%) patients had isolated, active IF MCP extension, 6/7 (86%) could extend IF MCP and thumb IP against resistance. Mean IF MCP extension was 1° ± 2°, mean IF MCP flexion was 89° ± 2°, mean thumb IP extension was -5° ± 4°, and mean thumb IP flexion was 67° ± 15°. Mean QuickDASH score was 16 ± 14. CONCLUSIONS: This series shows good long-term functional and patient reported outcomes in patients following extensor indicis proprius to EPL tendon transfers at a single center.

7.
J Am Chem Soc ; 145(12): 6741-6752, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36926879

RESUMO

Molecules that stabilize protein-protein interactions (PPIs) are invaluable as tool compounds for biophysics and (structural) biology, and as starting points for molecular glue drug discovery. However, identifying initial starting points for PPI stabilizing matter is highly challenging, and chemical optimization is labor-intensive. Inspired by chemical crosslinking and reversible covalent fragment-based drug discovery, we developed an approach that we term "molecular locks" to rapidly access molecular glue-like tool compounds. These dual-covalent small molecules reversibly react with a nucleophilic amino acid on each of the partner proteins to dynamically crosslink the protein complex. The PPI between the hub protein 14-3-3 and estrogen-related receptor γ (ERRγ) was used as a pharmacologically relevant case study. Based on a focused library of dual-reactive small molecules, a molecular glue tool compound was rapidly developed. Biochemical assays and X-ray crystallographic studies validated the ternary covalent complex formation and overall PPI stabilization via dynamic covalent crosslinking. The molecular lock approach is highly selective for the specific 14-3-3/ERRγ complex, over other 14-3-3 complexes. This selectivity is driven by the interplay of molecular reactivity and molecular recognition of the composite PPI binding interface. The long lifetime of the dual-covalent locks enabled the selective stabilization of the 14-3-3/ERRγ complex even in the presence of several other competing 14-3-3 clients with higher intrinsic binding affinities. The molecular lock approach enables systematic, selective, and potent stabilization of protein complexes to support molecular glue drug discovery.


Assuntos
Descoberta de Drogas , Receptores de Estrogênio , Humanos , Ligação Proteica , Proteínas 14-3-3/química , Aminoácidos/metabolismo
8.
Br J Haematol ; 200(6): 792-801, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36444397

RESUMO

The diagnostic work-up of patients referred to the haematologist for bleeding evaluation is performed in a stepwise way: bleeding history and results of screening laboratory tests guide further diagnostic evaluation. This can be ineffective, time-consuming and burdensome for patients. To improve this strategy, the initial laboratory investigation can be extended. In a model-based approach, effectiveness and costs of a conventional stepwise versus a newly proposed all-in-one diagnostic approach for bleeding evaluation were evaluated and compared, using data from an observational patient cohort study, including adult patients referred for bleeding evaluation. In the all-in-one approach, specialized platelet function tests, coagulation factors, and fibrinolysis tests were included in the initial investigation. Final diagnosis, hospital resource use and costs and patient burden were compared. A total of 150 patients were included. Compared to the stepwise approach, in the all-in-one approach, 19 additional patients reached a diagnosis and patient burden was lower, but total costs per patient were higher [€359, 95% bootstrapped confidence interval (BCI) 283-518, p = 0.001]. For bleeding evaluation of patients referred to the haematologist, an all-in-one diagnostic approach has a higher diagnostic yield and reduces patient burden, at a higher cost. This raises the question what costs justify the diagnosis of a bleeding disorder and a less burdensome diagnostic strategy.


Assuntos
Transtornos da Coagulação Sanguínea , Transtornos Hemorrágicos , Adulto , Humanos , Transtornos da Coagulação Sanguínea/diagnóstico , Transtornos Hemorrágicos/diagnóstico , Hemorragia , Fibrinólise , Análise Custo-Benefício
9.
Conserv Biol ; 37(4): e14084, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36919474

RESUMO

Estimates of temporal trends in species' occupancy are essential for conservation policy and planning, but limitations to the data and models often result in very high trend uncertainty. A critical source of uncertainty that degrades scientific credibility is that caused by disagreement among studies or models. Modelers are aware of this uncertainty but usually only partially estimate it and communicate it to decision makers. At the same time, there is growing awareness that full disclosure of uncertainty is critical for effective translation of science into policies and plans. But what are the most effective approaches to estimating uncertainty and communicating uncertainty to decision makers? We explored how alternative approaches to estimating and communicating uncertainty of species trends could affect decisions concerning conservation status of freshwater fishes. We used ensemble models to propagate trend uncertainty within and among models and communicated this uncertainty with categorical distributions of trend direction and magnitude. All approaches were designed to fit an established decision-making system used to assign species conservation status by the New Zealand government. Our results showed how approaches that failed to fully disclose uncertainty, while simplifying the information presented, could hamper species conservation or lead to ineffective decisions. We recommend an approach that was recently used effectively to communicate trend uncertainty to a panel responsible for setting the conservation status of New Zealand's freshwater fishes.


Designación del estado de conservación basada en tendencias a pesar de gran incertidumbre Resumen Las estimaciones de las tendencias temporales de la presencia de especies son esenciales para la planeación de la conservación y sus políticas, pero las limitaciones de los datos y los modelos suelen derivar en una incertidumbre muy elevada en cuanto a las tendencias. Los desacuerdos entre los estudios y los modelos son una fuente importante de incertidumbre que contribuye a la degradación de la credibilidad científica. Los modeladores están conscientes de esta incertidumbre, pero casi nunca la estiman o comunican por completo a los responsables de las decisiones. Al mismo tiempo, cada vez hay mayor conciencia de que divulgar esta incertidumbre es importante para que la ciencia se traduzca efectivamente en políticas y planes. ¿Pero cuáles son las estrategias más efectivas para estimar la incertidumbre y comunicarla a los responsables de las decisiones? Exploramos cómo las estrategias alternativas para estimar y comunicar la incertidumbre que rodea a las tendencias de las especies podría afectar las decisiones con respecto al estado de conservación de los peces de agua dulce. Usamos modelos de conjuntos para propagar la incertidumbre dentro y entre modelos y comunicamos esta incertidumbre con distribuciones categóricas de la dirección y magnitud de la tendencia. Diseñamos todas las estrategias para que se ajustaran a un sistema establecido de toma de decisiones que usa el gobierno de Nueva Zelanda para designar el estado de conservación de las especies. Nuestros resultados mostraron cómo las estrategias que no divulgaron por completo la incertidumbre, mientras simplificaban la información presentada, podrían dificultar la conservación de las especies o llevar a decisiones poco efectivas. Recomendamos una estrategia que se usó recientemente para comunicar eficientemente la incertidumbre de las tendencias a un panel responsable de establecer el estado de conservación de los peces de agua dulce de Nueva Zelanda.


Assuntos
Conservação dos Recursos Naturais , Peixes , Animais , Incerteza , Conservação dos Recursos Naturais/métodos , Políticas , Nova Zelândia
10.
MAGMA ; 36(1): 15-23, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36166103

RESUMO

OBJECTIVE: Recent work showed the feasibility of measuring velocity pulsatility in the perforating arteries at the level of the BG using 3T MRI. However, test-retest measurements have not been performed, yet. This study assessed the test-retest reliability of 3T MRI blood flow velocity measurements in perforating arteries in the BG. MATERIALS AND METHODS: Two-dimensional phase-contrast cardiac gated (2D-PC) images were acquired for 35 healthy controls and repeated with and without repositioning. 2D-PC images were processed and analyzed, to assess the number of detected perforating arteries (Ndetected), mean blood flow velocity (Vmean), and velocity pulsatility index (vPI). Paired t-tests and Bland-Altman plots were used to compare variance in outcome parameters with and without repositioning, and limits of agreement (LoA) were calculated. RESULTS: The LoA was smallest for Vmean (35%) and highest for vPI (79%). Test-retest reliability was similar with and without repositioning of the subject. DISCUSSION: We found similar LoA with and without repositioning indicating that the measurement uncertainty is dominated by scanner and physiological noise, rather than by planning. This enables to study hemodynamic parameters in perforating arteries at clinically available scanners, provided sufficiently large sample sizes are used to mitigate the contribution of scanner- and physiological noise.


Assuntos
Hemodinâmica , Imageamento por Ressonância Magnética , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Velocidade do Fluxo Sanguíneo/fisiologia , Gânglios da Base
11.
Br J Haematol ; 196(6): 1388-1400, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35001370

RESUMO

Patients referred for evaluation of bleeding symptoms occasionally have a prolonged platelet function analyser (PFA) closure time, without evidence for von Willebrand disease or impaired platelet aggregation. The aim of this study was to establish a shear-dependent platelet function defect in these patients. Patients were included based on high bleeding score and prior PFA prolongation. Common tests of von Willebrand factor (VWF) and platelet function and exome sequencing were performed. Microfluidic analysis of shear-dependent collagen-induced whole-blood thrombus formation was performed. In 14 PFA-only patients, compared to healthy volunteers, microfluidic tests showed significantly lower platelet adhesion and thrombus formation parameters. This was accompanied by lower integrin activation, phosphatidylserine exposure and P-selectin expression. Principal components analysis indicated VWF as primary explaining variable of PFA prolongation, whereas conventional platelet aggregation primarily explained the reduced thrombus parameters under shear. In five patients with severe microfluidic abnormalities, conventional platelet aggregation was in the lowest range of normal. No causal variants in Mendelian genes known to cause bleeding or platelet disorders were identified. Multiparameter assessment of whole-blood thrombus formation under shear indicates single or combined effects of low-normal VWF and low-normal platelet aggregation in these patients, suggesting a shear-dependent platelet function defect, not detected by static conventional haemostatic tests.


Assuntos
Trombose , Doenças de von Willebrand , Plaquetas/metabolismo , Hemorragia , Hemostasia , Humanos , Agregação Plaquetária , Testes de Função Plaquetária , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
12.
J Magn Reson Imaging ; 56(2): 527-535, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34997655

RESUMO

BACKGROUND: Increased cerebral blood-flow pulsatility is associated with cerebral small vessel disease (cSVD). Reduced pulsatility attenuation over the internal carotid artery (ICA) could be a contributing factor to the development of cSVD and could be associated with intracranial ICA calcification (iICAC). PURPOSE: To compare pulsatility, pulsatility attenuation, and distensibility along the ICA between patients with cSVD and controls and to assess the association between iICAC and pulsatility and distensibility. STUDY TYPE: Retrospective, explorative cross-sectional study. SUBJECTS: A total of 17 patients with cSVD, manifested as lacunar infarcts or deep intracerebral hemorrhage, and 17 age- and sex-matched controls. FIELD STRENGTH/SEQUENCE: Three-dimensional (3D) T1-weighted gradient echo imaging and 4D phase-contrast (PC) MRI with a 3D time-resolved velocity encoded gradient echo sequence at 7 T. ASSESSMENT: Blood-flow velocity pulsatility index (vPI) and arterial distensibility were calculated for seven ICA segments (C1-C7). iICAC presence and volume were determined from available brain CT scans (acquired as part of standard clinical care) in patients with cSVD. STATISTICAL TESTS: Independent t-tests and linear mixed models. The threshold for statistically significance was P < 0.05 (two tailed). RESULTS: The cSVD group showed significantly higher ICA vPI and significantly lower distensibility compared to controls. Controls showed significant attenuation of vPI over the carotid siphon (-4.9% ± 3.6%). In contrast, patients with cSVD showed no attenuation, but a significant increase of vPI (+6.5% ± 3.1%). iICAC presence and volume correlated positively with vPI (r = 0.578) in patients with cSVD and negatively with distensibility (r = -0.386). CONCLUSION: Decreased distensibility and reduced pulsatility attenuation are associated with increased iICAC and may contribute to cSVD. Confirmation in a larger prospective study is required. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 2.


Assuntos
Artéria Carótida Interna , Imageamento por Ressonância Magnética , Artéria Carótida Interna/diagnóstico por imagem , Hemorragia Cerebral , Estudos Transversais , Humanos , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
13.
Indoor Air ; 32(6): e13066, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35762236

RESUMO

Understanding airborne infectious disease transmission on public transport is essential to reducing the risk of infection of passengers and crew members. We propose a new one-dimensional (1D) model that predicts the longitudinal dispersion of airborne contaminants and the risk of disease transmission inside a railway carriage. We compare the results of this 1D-model to the predictions of a model that assumes the carriage is fully mixed. The 1D-model is validated using measurements of controlled carbon-dioxide experiments conducted in a full-scale railway carriage. We use our results to provide novel insights into the impact of various strategies to reduce the risk of airborne transmission on public transport.


Assuntos
Poluição do Ar em Ambientes Fechados , Poluição do Ar em Ambientes Fechados/análise , Dióxido de Carbono
14.
Indoor Air ; 32(10): e13121, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36305073

RESUMO

Experiments were conducted in an UK inter-city train carriage with the aim of evaluating the risk of infection to the SARS-CoV-2 virus via airborne transmission. The experiments included in-service CO2 measurements and the measurement of salt aerosol concentrations released within the carriage. Computational fluid dynamics simulations of the carriage airflow were also used to visualise the airflow patterns, and the efficacy of the HVAC filter material was tested in a laboratory. Assuming an infectious person is present, the risk of infection for a 1-h train journey was estimated to be 6 times lower than for a full day in a well-ventilated office, or 10-12 times lower than a full day in a poorly ventilated office. While the absolute risk for a typical journey is likely low, in the case where a particularly infectious individual is on-board, there is the potential for a number of secondary infections to occur during a 1-h journey. Every effort should therefore be made to minimize the risk of airborne infection within these carriages. Recommendations are also given for the use of CO2 sensors for the evaluation of the risk of airborne transmission on train carriages.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Humanos , SARS-CoV-2 , Dióxido de Carbono , Aerossóis e Gotículas Respiratórios
15.
Dis Aquat Organ ; 149: 109-120, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35678356

RESUMO

Detections of Renibacterium salmoninarum in Colorado USA fish hatcheries have become more frequent in recent years, including one disease outbreak that originated with a wild broodstock. Our objectives were to document the prevalence and distribution of R. salmoninarum in Colorado's wild trout fisheries, investigate variables that influence that distribution, and evaluate the effectiveness of common testing methods on non-anadromous trout. We sampled wild trout across Colorado and tested kidney tissue with enzyme-linked immunosorbent assay (ELISA), quantitative polymerase chain reaction (qPCR), nested polymerase chain reaction (nPCR), and direct fluorescent antibody test (DFAT). Screening with ELISA showed high prevalence of R. salmoninarum among fish populations, but antigen levels were low. No clinical disease was observed in any of the fish sampled despite the antigen of R. salmoninarum being common. Antigen levels measured by ELISA increased in smaller streams with lower historic fish stocking rates. Brook trout Salvelinus fontinalis had the highest prevalence of the bacterium among fish species and highest ELISA antigen levels. The distribution of brook trout in the smallest streams may help explain the patterns of R. salmoninarum across the landscape. The most effective assays for screening wild trout were qPCR and ELISA; DFAT was inconsistent for bacterial levels encountered in wild trout and generally uninformative. Additionally, qPCR and ELISA can provide quantitative information about bacteria levels. The bacterium R. salmoninarum is ubiquitous in Colorado trout fisheries but is generally found at low levels. Active infections are rare and overt bacterial kidney disease appears more common in Colorado hatcheries than in wild fish.


Assuntos
Infecções Bacterianas , Doenças dos Peixes , Nefropatias , Micrococcaceae , Animais , Infecções Bacterianas/veterinária , Colorado/epidemiologia , Doenças dos Peixes/microbiologia , Pesqueiros , Rim , Nefropatias/epidemiologia , Nefropatias/veterinária , Micrococcaceae/genética , Prevalência , Renibacterium , Truta
16.
Proc Natl Acad Sci U S A ; 116(11): 4893-4898, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30804199

RESUMO

Green water--rainfall over land that eventually flows back to the atmosphere as evapotranspiration--is the main source of water to produce food, feed, fiber, timber, and bioenergy. To understand how freshwater scarcity constrains production of these goods, we need to consider limits to the green water footprint (WFg), the green water flow allocated to human society. However, research traditionally focuses on scarcity of blue water--groundwater and surface water. Here we expand the debate on water scarcity by considering green water scarcity (WSg). At 5 × 5 arc-minute spatial resolution, we quantify WFg and the maximum sustainable level to this footprint (WFg,m), while accounting for green water requirements to support biodiversity. We then estimate WSg per country as the ratio of the national aggregate WFg to the national aggregate WFg,m We find that globally WFg amounts to 56% of WFg,m, and overshoots it in several places, for example in countries in Europe, Central America, the Middle East, and South Asia. The sustainably available green water flows in these countries are mostly or fully allocated to human activities (predominately agriculture and forestry), occasionally at the cost of green water flows earmarked for nature. By ignoring limits to the growing human WFg, we risk further loss of ecosystem values that depend on the remaining untouched green water flows. We emphasize that green water is a critical and limited resource that should explicitly be part of any assessment of water scarcity, food security, or bioenergy potential.


Assuntos
Biocombustíveis , Alimentos , Chuva , Recursos Hídricos , Madeira , Geografia , Humanos
17.
Environ Manage ; 69(5): 952-971, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35107602

RESUMO

A key aspect of contemporary fish habitat management is the need to account for losses and gains associated with development and offsetting measures while protecting high quality features. We propose an ecological accounting framework for aquatic ecosystems using habitat equivalents scaled to aquatic productivity, and using fish-to-habitat associations by life stage, based on local fish community needs. The framework uses both landscape-scale and site-level evaluations of pre- and post-project habitat changes to assign and track habitat parcels, using ecological baselines and fish-habitat target setting. Concepts of natural capital reserves and productivity-based ecotypes are used for trading losses and gains between impacts from development projects and offsets, including restoration actions, while maintaining ecologically important areas intact. Traditional accounting terms such as deposits, withdrawals, and transfers are defined using scaled habitat-equivalents as the currency. Other key features of the framework include setting a service area that is ecologically meaningful, and conducting habitat transactions guided by habitat conservation, protection, and restoration (habitat CPR) principles. The nearshore area of the Toronto and Region is used as a case study to illustrate the eco-accounting framework and how habitat banking could be incorporated along with planned restoration to remediate this degraded but continually developed area. The framework represents significant advances in managing cumulative habitat effects in an integrated way, moving away from a focus on only project- or site-level assessments. We feel this approach could be adapted to other ecosystem types in addition to the lake, nearshore area example provided here.


Assuntos
Ecossistema , Peixes , Animais , Lagos , Ontário
18.
Popul Stud (Camb) ; 75(1): 91-110, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32056500

RESUMO

It remains unknown how different types of sources affect the reconstruction of life courses and families in large-scale databases increasingly common in demographic research. Here, we compare family and life-course reconstructions for 495 individuals simultaneously present in two well-known Dutch data sets: LINKS, based on the Zeeland province's full-population vital event registration data (passive registration), and the Historical Sample of the Netherlands (HSN), based on a national sample of birth certificates, with follow-up of individuals in population registers (active registration). We compare indicators of fertility, marriage, mortality, and occupational status, and conclude that reconstructions in the HSN and LINKS reflect each other well: LINKS provides more complete information on siblings and parents, whereas the HSN provides more complete life-course information. We conclude that life-course and family reconstructions based on linked passive registration of individuals constitute a reliable alternative to reconstructions based on active registration, if case selection is carefully considered.


Assuntos
Fertilidade , Casamento , Coeficiente de Natalidade , Humanos , Países Baixos , Dinâmica Populacional , Sistema de Registros
19.
Public Health Nurs ; 38(1): 4-12, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33216399

RESUMO

BACKGROUND: Oil development (OD) has been associated with increased sexually transmitted infection (STI) rates, with limited focus on the North Dakota (ND) oil boom. Public health (PH) nurse experiences can provide context related to health challenges during OD-related population booms. OBJECTIVE: To compare reported STI rates in ND oil-producing (OP) and non-oil-producing (NOP) counties before, during, and after the oil boom and describe PH nurse experiences during this time. DESIGN: We conducted secondary data analysis of oil production data and reported rates for chlamydia and gonorrhea, and conducted interviews with ND PH nurses. SAMPLE: PH nurses within ND counties geographically located in or near OD in the state. MEASUREMENTS: ND county-level OD data trends were compared to similarly timed reported rates of chlamydia and gonorrhea in OP and NOP counties. PH nurse interviews were conducted addressing their STI-related experiences working in PH during the oil boom. RESULTS: Significant findings include a correlation between OD and gonorrhea rates. PH nurses described a limited PH infrastructure to meet the health needs of a transient, increasing population. CONCLUSIONS: Expanding the role of PH nurses in ND to implement STI screening and treatment would improve access to STI testing allowing for comprehensive reporting of STIs.


Assuntos
Enfermeiros de Saúde Pública , Indústria de Petróleo e Gás , Infecções Sexualmente Transmissíveis , Saúde Global/estatística & dados numéricos , Humanos , North Dakota/epidemiologia , Enfermeiros de Saúde Pública/psicologia , Indústria de Petróleo e Gás/estatística & dados numéricos , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/enfermagem
20.
Glob Chang Biol ; 26(12): 6880-6894, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32970901

RESUMO

In the world's rivers, alteration of flow is a major driver of biodiversity decline. Global warming is now affecting the thermal and hydrological regimes of rivers, compounding the threat and complicating conservation planning. To inform management under a non-stationary climate, we must improve our understanding of how flow and thermal regimes interact to affect the population dynamics of riverine biota. We used long-term growth biochronologies, spanning 34 years and 400,000 km2 , to model the growth dynamics of a long-lived, apex predator (Murray cod) as a function of factors extrinsic (river discharge; air temperature; sub-catchment) and intrinsic (age; individual) to the population. Annual growth of Murray cod showed significant, curvilinear, life-stage-specific responses to an interaction between annual discharge and temperature. Growth of early juveniles (age 1+ and 2+ years) exhibited a unimodal relationship with annual discharge, peaking near median annual discharge. Growth of late juveniles (3+ to 5+) and adults (>5+) increased with annual discharge, with the rate of increase being particularly high in adults, whose growth peaked during years with flooding. Years with very low annual discharge, as experienced during drought and under high abstraction, suppress growth rates of all Murray cod life-stages. Unimodal relationships between growth and annual temperature were evident across all life stages. Contrary to expectations of the Temperature Size Rule, the annual air temperature at which maximum growth occurred increased with age. The stage-specific response of Murray cod to annual discharge indicates that no single magnitude of annual discharge is optimal for cod populations, adding further weight to the case for maintaining and/or restoring flow variability in riverine ecosystems. With respect to climate change impacts, on balance our results indicate that the primary mechanism by which climate change threatens Murray cod growth is through alteration of river flows, not through warming annual mean temperatures per se.


Assuntos
Ecossistema , Rios , Mudança Climática , Hidrologia , Temperatura
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