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1.
Aging Ment Health ; 28(3): 551-556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37545400

RESUMO

OBJECTIVES: Suicide in late life is a public health concern. Determining profiles of psychiatric/medical comorbidity in those who attempt while engaged in mental health services may assist with prevention. We identified comorbidity profiles and their association with utilization, means, and fatality in a national sample who attempted suicide. METHODS: Using latent class analysis, all patients aged ≥ 65 from the Department of Veterans Affairs (VA) healthcare services (2012-2018) last seen in mental health prior to suicide attempt were included. Diagnoses and attempt data were obtained from VA and Center for Medicare & Medicaid Services, VA Suicide Prevention Applications Network, and VA National Mortality Data Repository. RESULTS: 2,269 patients were clustered into three profiles, all with high probability of depression. Profiles included minimal comorbidity (50.4%), high medical comorbidity (28.6%), and high (psychiatric/medical) comorbidity (21.0%). Over half (61.7%) attempted suicide within one week of their visit. The class with highest comorbidity had lowest proportion of fatal attempts, while minimal comorbidity class had highest proportion. CONCLUSIONS: Older patients last seen in mental health prior to suicide attempt were characterized by depression and varying additional comorbidity and attempt-related factors. Findings have implications for risk assessment and intervention in mental health settings, beyond depression.


Assuntos
Tentativa de Suicídio , Veteranos , Humanos , Idoso , Estados Unidos/epidemiologia , Tentativa de Suicídio/psicologia , Saúde Mental , Medicare , Comorbidade , Prevenção do Suicídio , Veteranos/psicologia
2.
J Appl Clin Med Phys ; 25(5): e14295, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38335253

RESUMO

PURPOSE/OBJECTIVE: Field size limitations on Halcyon and Ethos treatment machines largely preclude use of the conventional monoisocentric three-field technique for breast/chest wall and regional lymph nodes. We present an alternative, IMRT-based planning approach that facilitates treatment on Halcyon and Ethos while preserving plan quality. MATERIALS/METHODS: Eight breast and regional node cases (four left-sided, four right-sided) were planned for an Ethos machine using a 15-17 field IMRT technique. Institutional plan quality metrics for CTV and PTV coverage and OAR sparing were assessed. Five plans (four right-sided, one left-sided) were also planned using a hybrid 3D multisocenter technique. CTV coverage and OAR sparing were compared to the IMRT plans. Eclipse scripting tools were developed to aid in beam placement and plan evaluation through a set of dosimetric scorecards, and both are shared publicly. RESULTS: On average, the IMRT plans achieved breast CTV and PTV coverage at 50 Gy of 97.9% and 95.7%, respectively. Supraclavicular CTV and PTV coverages at 45 Gy were 100% and 95.5%. Axillary lymph node CTV and PTV coverages at 45 Gy were 100% and 97.1%, and IMN CTV coverage at 45 Gy was 99.2%. Mean ipsilateral lung V20 Gy was 19.3%, and average mean heart dose was 1.6 Gy for right-sided cases and 3.0 Gy for left-sided. In comparison to the hybrid 3D plans, IMRT plans achieved higher breast and supraclavicular CTV coverage (99.9% vs. 98.6% and 99.9% vs. 93.4%), higher IMN coverage (99.6% vs. 78.2%), and lower ipsilateral lung V20 Gy (19.6% vs. 28.2%). CONCLUSION: Institutional plan quality benchmarks were achieved for all eight cases using the IMRT-based planning approach. The IMRT-based planning approach offered superior conformity and OAR sparing than a competing hybrid 3D approach.


Assuntos
Neoplasias da Mama , Linfonodos , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Parede Torácica , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Feminino , Parede Torácica/efeitos da radiação , Órgãos em Risco/efeitos da radiação , Neoplasias da Mama/radioterapia , Linfonodos/efeitos da radiação
3.
J Therm Biol ; 120: 103814, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38402729

RESUMO

Urbanization alters natural landscapes and creates unique challenges for urban wildlife. Similarly, the Urban Heat Island (UHI) effect can produce significantly elevated temperatures in urban areas, and we have a relatively poor understanding of how this will impact urban biodiversity. In particular, most studies quantify the UHI using broad-scale climate data rather than assessing microclimate temperatures actually experienced by organisms. In addition, studies often fail to address spatial and temporal complexities of the UHI. Here we examine the thermal microclimate and UHI experienced in the web of Western black widow spiders (Latrodectus hesperus), a medically-important, superabundant urban pest species found in cities across the Western region of North America. We do this using replicate urban and desert populations across an entire year to account for seasonal variation in the UHI, both within and between habitats. Our findings reveal a strong nighttime, but no daytime, UHI effect, with urban spider webs being 2-5 °C warmer than desert webs at night. This UHI effect is most prominent during the spring and least prominent in winter, suggesting that the UHI need not be most pronounced when temperatures are most elevated. Urban web temperatures varied among urban sites in the daytime, whereas desert web temperatures varied among desert sites in the nighttime. Finally, web temperature was significantly positively correlated with a spider's boldness, but showed no relationship with voracity towards prey, web size, or body condition. Understanding the complexities of each organism's thermal challenges, the "functional microclimate", is crucial for predicting the impacts of urbanization and climate change on urban biodiversity and ecosystem functioning.


Assuntos
Artrópodes , Viúva Negra , Animais , Temperatura , Temperatura Alta , Cidades , Microclima , Ecossistema
4.
Am J Geriatr Psychiatry ; 31(7): 525-539, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36494291

RESUMO

Older veterans are vastly underrepresented in studies that shape national suicide prevention strategies. This is of great concern because factors that impact younger veterans may not be as robust in later life. Although younger veterans have higher rate of suicide, the highest counts of death by suicide are in older veterans. However, it remains unclear from the extant literature what factors may influence increased or decreased risk of late-life suicide in veterans. The objective of this systematic review was to identify risk and protective factors related to suicide outcomes (i.e., ideation, attempt, death, or suicide-related behavior [SRB]) among older veterans. Furthermore, it offers data regarding future study directions and hypothesis generation for late-life suicide research and for informing potential intervention and prevention efforts in this area. We searched 4 databases from inception up to May 5, 2022. We screened 2,388 abstracts for inclusion and 508 articles required full text review. The final sample included 19 studies published between 2006 and 2022. We found five domains of factors studied (i.e., neuropsychiatric, social determinants of health, aging stereotypes, residential and supportive housing settings, and multifactorial-neuropsychiatric/mental health and physical health) with more risk factors than protective factors reported. Across the three suicide outcomes only neuropsychiatric factors were consistently identified as risk factors. Neuropsychiatric factors also comprised the largest group of risk factors studied. More innovative targets to consider for intervention and more innovative methods to predict suicide in late-life are needed. There is also continued necessity to design suicide prevention interventions for older veterans given lethality trends.


Assuntos
Suicídio , Veteranos , Humanos , Idoso , Veteranos/psicologia , Ideação Suicida , Prevenção do Suicídio , Fatores de Risco
5.
Med Teach ; 45(1): 58-67, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35981566

RESUMO

BACKGROUND: Doctors are increasingly expected to demonstrate medical leadership and management (MLM) skills. The Faculty of Medical Leadership and Management (FMLM) has published an indicative undergraduate curriculum to guide the development of MLM content at UK medical schools. METHOD: Students from 30 medical schools were surveyed to determine their understanding of MLM teaching at their school. Timetables for 21 schools were searched for MLM-related keywords. Student-reported teaching and timetabled teaching were coded according to predefined themes. Aggregated demographic and postgraduate performance data were obtained through collaboration with the Medical Student Investigators Collaborative (msico.org). RESULTS: Whilst 88% of medical students see MLM teaching as relevant, only 18% believe it is well integrated into their curriculum. MLM content represented ∼2% of timetabled teaching in each 5-year undergraduate medical course. Most of this teaching was dedicated to teamwork, performance/reflection and communication skills. There was minimal association between how much of a topic students believed they were taught, and how much they were actually taught. We found no association between the volume of MLM teaching and performance in postgraduate examinations, trainee career destinations or fitness to practice referrals. CONCLUSION: Our findings demonstrate limited and variable teaching of MLM content. Delivery was independent of broader teaching and assessment factors.


Assuntos
Educação de Graduação em Medicina , Humanos , Liderança , Faculdades de Medicina , Currículo , Reino Unido
6.
Sensors (Basel) ; 23(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37514889

RESUMO

Space situational awareness (SSA) refers to collecting, analyzing, and keeping track of detailed knowledge of resident space objects (RSOs) in the space environment. With the rapidly increasing number of objects in space, the need for SSA grows as well. Traditional methods rely heavily on imaging RSOs from large, narrow field-of-view (FOV), ground-based telescopes. This research outlines the technology demonstration payload, Resident Space Object Near-space Astrometric Research (RSONAR)-a star tracker-like, wide FOV camera combined with commercial off-the-shelf (COTS) hardware to image RSOs from the stratosphere, overcoming the disadvantages of ground-based observations. The hardware components and software algorithm are described and evaluated. The eligibility of the payload for SSA is proven by the image processing algorithms, which detect the RSOs in the images captured during flight and the survival of the COTS components in the near-space environment. The payload features a low-resolution, wide FOV camera coupled with a Field Programmable Gate Array (FPGA)-based platform that houses the altitude and time-based image capture algorithm. The newly developed payload in a 2U-CubeSat form factor was flown as a space-ready payload on the CSA/CNES stratospheric balloon research platform to carry out algorithm and functionality tests in August 2022.

7.
Mol Syst Biol ; 17(10): e10355, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34693621

RESUMO

Understanding the principles of colonization resistance of the gut microbiome to the pathogen Clostridioides difficile will enable the design of defined bacterial therapeutics. We investigate the ecological principles of community resistance to C. difficile using a synthetic human gut microbiome. Using a dynamic computational model, we demonstrate that C. difficile receives the largest number and magnitude of incoming negative interactions. Our results show that C. difficile is in a unique class of species that display a strong negative dependence between growth and species richness. We identify molecular mechanisms of inhibition including acidification of the environment and competition over resources. We demonstrate that Clostridium hiranonis strongly inhibits C. difficile partially via resource competition. Increasing the initial density of C. difficile can increase its abundance in the assembled community, but community context determines the maximum achievable C. difficile abundance. Our work suggests that the C. difficile inhibitory potential of defined bacterial therapeutics can be optimized by designing communities featuring a combination of mechanisms including species richness, environment acidification, and resource competition.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Microbioma Gastrointestinal , Bactérias , Clostridioides , Infecções por Clostridium/tratamento farmacológico , Humanos
8.
J Chem Phys ; 156(20): 204312, 2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35649863

RESUMO

Ionic liquids (ILs) are novel promising materials widely used in various fields. Their structures and properties can be tuned by means of external perturbations, thus further broadening their applications. Herein, forces proportional to atomic mass (mass-related field) and atomic charge (electric field) are applied in molecular dynamics simulations to the IL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide to investigate the origin of the resulting changes in structures and dynamics. The results show that both electric and mass-related fields cause the ion cages to expand and deform, eventually leading to their breakdown to produce a transformation of ILs from the cage structure to a channel-like structure, which results in faster self-diffusion of ions in the directions of the applied force and to a lesser extent other directions. Further comparison of electric and mass-related fields demonstrates that only the electric fields reorientate cations to produce a hydrodynamically favored conformation in the force direction, which shows faster diffusion. The cis isomer of the anion is preferred in the presence of the electric fields, whereas applying the forces proportional to mass does not change the anion conformer equilibrium significantly. The results presented in this work aid in the understanding of how ions adjust their structures to adapt to external perturbations and facilitate the application of ILs as electrolytes.

9.
J Biomech Eng ; 144(7)2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34951462

RESUMO

Most motion capture measurements suffer from soft-tissue artifacts (STA). Especially affected are rotations about the long axis of a limb segment, such as humeral internal-external rotation (HIER) and forearm pronation-supination (FPS). Unfortunately, most existing methods to compensate for STA were designed for optoelectronic motion capture systems. We present and evaluate an STA compensation method that (1) compensates for STA in HIER and/or FPS, (2) is developed specifically for electromagnetic motion capture systems, and (3) does not require additional calibration or data. To compensate for STA, calculation of HIER angles relies on forearm orientation, and calculation of FPS angles rely on hand orientation. To test this approach, we recorded whole-arm movement data from eight subjects and compared their joint angle trajectories calculated according to progressive levels of STA compensation. Compensated HIER and FPS angles were significantly larger than uncompensated angles. Although the effect of STA compensation on other joint angles (besides HIER and FPS) was usually modest, significant effects were seen in certain degrees-of-freedom under some conditions. Overall, the method functioned as intended during most of the range of motion of the upper limb, but it becomes unstable in extreme elbow extension and extreme wrist flexion-extension. Specifically, this method is not recommended for movements within 20 deg of full elbow extension, full wrist flexion, or full wrist extension. Since this method does not require additional calibration of data, it can be applied retroactively to data collected without the intent to compensate for STA.


Assuntos
Artefatos , Extremidade Superior , Fenômenos Biomecânicos , Fenômenos Eletromagnéticos , Humanos , Movimento , Pronação , Amplitude de Movimento Articular , Supinação
10.
Sensors (Basel) ; 22(15)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35957245

RESUMO

A catalogue of over 22,000 objects in Earth's orbit is currently maintained, and that number is expected to double within the next decade. Novel data collection regimes are needed to scale our ability to detect, track, classify and characterize resident space objects in a crowded low Earth orbit. This research presents RSOnet, an image-processing framework for space domain awareness using star trackers. Star trackers are cost-effective, flight proven, and require basic image processing to be used as an attitude-determination sensor. RSOnet is designed to augment the capabilities of a star tracker by becoming an opportunistic space-surveillance sensor. Our research demonstrates that star trackers are a feasible source for RSO detections in LEO by demonstrating the performance of RSOnet on real detections from a star-tracker-like imager in space. RSOnet convolutional-neural-network model architecture, graph-based multi-object classifier and characterization results are described in this paper.

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