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1.
Mil Med ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877896

RESUMO

INTRODUCTION: The U.S. Army Aeromedical Research Laboratory (USAARL), a partner in the Joint Trauma Analysis for the Prevention of Injury in Combat (JTAPIC) partnership, conducted a series of retrospective reviews to investigate injuries sustained by occupants of U.S. Army rotary-wing aircraft involved in combat damage incidents. The reviews were conducted to provide occupant survivability information to the Aviation Survivability Development and Tactics team, an agency within the U.S. Army Aviation Center of Excellence. For these reviews, combat damage incidents that produced casualties were separated into direct events (i.e., events in which an enemy weapon system directly injured occupants) and indirect events (i.e., incidents in which occupants were injured as a result of a crash caused by the enemy weapon system). The previous USAARL reviews provided an overview of injuries sustained during direct and indirect events. The objective of this review was to conduct a detailed analysis of injuries occurring during direct events. MATERIALS AND METHODS: A descriptive retrospective review was conducted on injuries sustained by occupants of U.S. Army rotary-wing aircraft involved in combat damage incidents between 2003 and 2014. All Black Hawk, Apache, and Chinook combat aviation damage incidents for the study period were reviewed. Personnel casualty information from the Defense Casualty Information Processing System (DCIPS) was linked to combat damage incident information by matching the aircraft platform, incident date, and circumstantial information found in incident narratives. Injury information for personnel identified in DCIPS as being wounded in action was obtained from the JTAPIC partnership; injury data for personnel killed in action were retrieved from the Armed Forces Medical Examiner System. All injuries were coded using the Abbreviated Injury Scale (AIS). Descriptive statistics were used to describe the frequency and distribution of injuries to personnel involved in direct events. RESULTS: Overall, the extremities were the most commonly injured body regions, with lower extremities suffering more injuries than upper extremities. Penetrating injuries were identified as the primary injury mechanism for all body regions. Injuries to each AIS body region were predominantly of minor (AIS 1) and moderate (AIS 2) severity. CONCLUSIONS: Although injury severities were generally low (AIS 1 or AIS 2), the results of this effort indicate which body regions may benefit from additional protection during rotary-wing operations in hostile environments. The influence of occupant position within the aircraft and the use and effectiveness of personal protective equipment could not be effectively analyzed due to a lack of information.

2.
Vet Parasitol ; 328: 110168, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38547830

RESUMO

Cyathostomins are globally important equine parasites, responsible for both chronic and acute pathogenic effects. The occurrence of mixed infections with numerous cyathostomin species hinders our understanding of parasite epidemiology, host-parasite dynamics, and species pathogenicity. There have been few studies of cyathostomin species occurring in horses in Ireland, where temperate climatic conditions with year-round rainfall provide suitable conditions for infection of grazing animals with bursate nematodes. Here, we amplified and sequenced the ITS-2 region of adult worms harvested at post-mortem from eleven adult horses between August 2018 and June 2020, and recorded species prevalence and abundance of worms recovered from the caecum, right ventral colon and left dorsal colon, using both BLAST and IDTAXA for taxonomic attribution. Phylogenetic relationships and community composition were also recorded and compared with other relevant studies, including a global meta-analysis. Overall, our results agree with previous studies that there does not seem to be a major difference in cyathostomin species occurrence in equids in different geographical regions. We confirmed the results of other workers in relation to the difficulties in discriminating between Cylicostephanus calicatus and Coronocyclus coronatus on the basis of ITS-2 sequences.


Assuntos
Doenças dos Cavalos , Filogenia , Animais , Cavalos , Irlanda/epidemiologia , Doenças dos Cavalos/parasitologia , Doenças dos Cavalos/epidemiologia , Strongyloidea/classificação , Strongyloidea/isolamento & purificação , Strongyloidea/genética
3.
Phys Chem Chem Phys ; 26(8): 6646-6654, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38329232

RESUMO

Rate coefficients (k4) for the reaction of hydroxyl radicals (OH) with methyl nitrate (CH3ONO2) were measured over the temperature range 232-343 K using pulsed laser photolysis to generate OH and pulsed laser-induced fluorescence to detect it in real-time and under pseudo-first-order conditions. In order to optimize the accuracy of the rate coefficients obtained, the concentration of CH3ONO2 (the reactant in excess) was measured on-line by absorption spectroscopy at 213.86 nm for which the absorption cross-section was also measured (σ213.86 = 1.65 ± 0.09 × 10-18 cm2 molecule-1). The temperature-dependent rate coefficient is described by k4(T) = 7.5 × 10-13 exp[(-1034 ± 40)/T] cm3 molecule-1 s-1 with a room temperature rate coefficient of k4(296 ± 2 K) = (2.32 ± 0.12) × 10-14 cm3 molecule-1 s-1 where the uncertainty includes the statistical error of 2σ and an estimation of the potential systematic bias of 5%. This new dataset helps to consolidate the database for this rate coefficient and to reduce uncertainty in the atmospheric lifetime of CH3ONO2. As part of this study, an approximate rate coefficient for the reaction of H-atoms with CH3ONO2 (k9) was also derived at room temperature: k9(298 K) = (1.68 ± 0.45) × 10-13 cm3 molecule-1 s-1.

4.
J Cancer Educ ; 38(5): 1683-1689, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37368119

RESUMO

We designed and tested the feasibility of the Smoking Cessation Training Program for Oncology Practice (STOP), a hybrid (face-to-face plus web-based) educational intervention to enhance Spanish-speaking cancer care professionals' (CCPs') ability to provide brief smoking prevention and cessation counseling to cancer patients and survivors. Changes in the CCPs' competencies (knowledge, attitude, self-efficacy, and practices toward smoking and smoking cessation services) were assessed post-training. Sixty CCPs from one major cancer center in Colombia (n = 30) and Peru (n = 30) were invited to participate in a 4-module hybrid training program on smoking prevention and cessation. Demographic and pre- and post-test evaluation data were collected. The training's acceptability was measured after each module. Bivariate analysis was conducted using Wilcoxon signed-rank test to compare the CCPs' competencies before and after the delivery of the STOP Program. Effect sizes were computed over time to assess the sustainability of the acquired competencies. Twenty-nine CCPs in Colombia and 24 CCPs in Peru completed the STOP Program (96.6% and 80.0% retention rates, respectively). In both countries, 98.2% of the CCPs reported that the overall structure and organization of the program provided an excellent learning experience. The pre-post-test evaluations indicated that the CCPs significantly improved their knowledge, attitude, self-efficacy, and practices toward smoking, smoking prevention, and cessation services. We found that the CCPs' self-efficacy and practices increased over time (1-, 3-, and 6-month assessments after completing the 4 educational modules). The STOP Program was effective and well-received, demonstrating remarkable changes in CCPs' competencies in providing smoking prevention and cessation services to cancer patients.


Assuntos
Neoplasias , Abandono do Hábito de Fumar , Humanos , Prevenção do Hábito de Fumar , Colômbia , Peru , Fumar , Neoplasias/prevenção & controle
5.
Health Commun ; 38(8): 1621-1630, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-35057677

RESUMO

Research indicates that misperceptions that become part of people's initial mental models about an issue tend to persist and influence their attitudes even after the misperception has been corrected. Recent work on evolving mental models suggests that communication efforts about the ongoing COVID-19 pandemic and its aftermath may be improved by crafting messages that acknowledge biases and misunderstandings about the virus and other infectious diseases that may remain among members of the target audience. This study was designed to provide insight into such biases by: (1) establishing salient categories of COVID-related misperceptions in the earliest months of the pandemic in the United States among (a) the general population, and (b) demographic sub-populations at high risk of severe health outcomes; (2) identifying demographic predictors of misperceptions; and (3) examining the relationship between consumption of different television news outlets and agreement with misperceptions about COVID-19. A national sample of 1,000 adults in the United States (48.1% male; M age = 47.32, SD = 18.01; 72.9% White/Caucasian, 14.3% Black/African American, 15.9% Hispanic/Latinx) completed a survey between March 19 and March 25, 2020. Results identify prevalent classes of salient early COVID-19 misperceptions. Adjusting for numerous covariates, data indicated individuals over the age of 60 held the fewest COVID-related misperceptions among various demographic sub-populations, misperceptions were most prevalent among Black respondents, and increased consumption of television network news was associated with lower levels of misperception. Consumption of some 24-hour news networks (FOX and MSNBC) were significant positive correlates of misperceptions.


Assuntos
COVID-19 , Desinformação , Meios de Comunicação de Massa , Televisão , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , COVID-19/epidemiologia , COVID-19/psicologia , Pandemias , SARS-CoV-2 , Estados Unidos/epidemiologia , Idoso
6.
Front Med (Lausanne) ; 9: 964448, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36250086

RESUMO

Acute hepatic failure is associated with high morbidity and mortality for which the only definitive therapy is liver transplantation. Some fraction of those who undergo emergency transplantation have been shown to recover native liver function when transplanted with an auxiliary hepatic graft that leaves part of the native liver intact. Thus, transplantation could have been averted with the development and use of some form of hepatic support. The costs of developing and testing liver support systems could be dramatically reduced by the availability of a reliable large animal model of hepatic failure with a large therapeutic window that allows the assessment of efficacy and timing of intervention. Non-lethal forms of hepatic injury were examined in combination with liver-directed radiation in non-human primates (NHPs) to develop a model of acute hepatic failure that mimics the human condition. Porcine hepatocyte transplantation was then tested as a potential therapy for acute hepatic failure. After liver-directed radiation therapy, delivery of a non-lethal hepatic ischemia-reperfusion injury reliably and rapidly generated liver failure providing conditions that can enable pre-clinical testing of liver support or replacement therapies. Unfortunately, in preliminary studies, low hepatocyte engraftment and over-immune suppression interfered with the ability to assess the efficacy of transplanted porcine hepatocytes in the model. A model of acute liver failure in NHPs was created that recapitulates the pathophysiology and pathology of the clinical condition, does so with reasonably predictable kinetics, and results in 100% mortality. The model allowed preliminary testing of xenogeneic hepatocyte transplantation as a potential therapy.

7.
J Anim Sci ; 100(12)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36268991

RESUMO

Rumen methanogenesis results in the loss of 6% to 10% of gross energy intake in cattle and globally is the single most significant source of anthropogenic methane (CH4) emissions. The purpose of this study was to analyze greenhouse gas traits recorded in a commercial feedlot unit to gain an understanding into the relationships between greenhouse gas traits and production traits. Methane and carbon dioxide (CO2) data recorded via multiple GreenFeed Emission Monitoring (GEM), systems as well as feed intake, live weight, ultrasound scanning data, and slaughter data were available on 1,099 animals destined for beef production, of which 648 were steers, 361 were heifers, and 90 were bulls. Phenotypic relationships between GEM emission measurements with feed intake, weight traits, muscle ultrasound data, and carcass traits were estimated. Utilization of GEM systems, daily patterns of methane output, and repeatability of GEM system measurements across averaging periods were also assessed. Methane concentrations varied with visit number, duration, and time of day of visit to the GEM system. Mean CH4 and CO2 varied between sex, with mean CH4 of 256.1 g/day ± 64.23 for steers, 234.7 g/day ± 59.46 for heifers, and 156.9 g/day ± 55.98 for young bulls. A 10-d average period of GEM system measurements were required for steers and heifers to achieve a minimum repeatability of 0.60; however, higher levels of repeatability were observed in animals that attended the GEM system more frequently. In contrast, CO2 emissions reached repeatability estimates >0.6 for steers and heifers in all averaging periods greater than 2-d, suggesting that cattle have a moderately consistent CO2 emission pattern across time periods. Animals with heavier bodyweights were observed to have higher levels of CH4 (correlation = 0.30) and CO2 production (correlation = 0.61), and when assessing direct methane, higher levels of dry matter intake were associated with higher methane output (correlation = 0.31). Results suggest that reducing CH4 can have a negative impact on growth and body composition of cattle. Methane ratio traits, such as methane yield and intensity were also evaluated, and while easy to understand and compare across populations, ratio traits are undesirable in animal breeding, due to the unpredictable level of response. Methane adjusted for dry matter intake and liveweight (Residual CH4) should be considered as an alternative emission trait when selecting for reduced emissions within breeding goals.


Methane production from cattle digestion results in the loss of 6% to 10% of gross energy intake in cattle and globally is the single most significant source of anthropogenic methane (CH4) emissions. The purpose of this study was to analyze greenhouse gas traits recorded in a commercial feedlot unit to gain an understanding into the relationships between greenhouse gas traits and production traits of economic importance. Methane and carbon dioxide emissions recorded using Greenfeed systems were available on a total of 1,099 animals. In addition, performance indicators such as feed intake, live weight, ultrasound scanning data, and slaughter data were also available on all animals. Phenotypic repeatability of CH4 ranged from 0.13 to 0.74, with a CH4 repeatability of >0.6 achieved by both heifers and steers in 10-d measuring period. Due to the high repeatability of CH4 measures, an accurate portrayal of CH4 production can be observed from a 10-d measuring period when measures are averaged. Methane emission data were positively correlated with traits of economic importance. Phenotypically, animals with heavier body weights and greater feed intake had higher emissions.


Assuntos
Gases de Efeito Estufa , Metano , Bovinos/genética , Animais , Feminino , Masculino , Dieta/veterinária , Ingestão de Alimentos , Rúmen , Ração Animal/análise
9.
J Phys Chem A ; 126(24): 3863-3872, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35675113

RESUMO

The termolecular, association reaction between OH and NO is a source of nitrous acid (HONO), an important atmospheric trace gas. Rate coefficients for the title reaction as recommended by evaluation panels differ substantially at the temperatures and pressures that prevail in the Earth's boundary layer where the reaction is in the fall-off regime between low- and high-pressure limiting rate coefficients. Using pulsed laser methods for generation and detection of OH, we have reinvestigated the kinetics of the title reaction at pressures of 22-743 Torr (1 Torr = 1.333 hPa) and temperatures (273, 298, and 333 K) in pure N2 and in N2-H2O bath gases. In situ optical absorption measurements were used to rule out any bias due to NO2 or HONO impurities. Our rate coefficients (k1) in N2 bath gas are parametrized in terms of low-pressure (k0) and high-pressure (k∞) rate coefficients and a fall-off parameter (FC) with k1,0N2 = 7.24 × 10-31 (T/300 K)-2.17 cm6 molecule-2 s-1, k1,∞ = 3.3 × 10-12 (T/300 K)-0.3 cm3 molecule-1 s-1, and FC = 0.53. Used with the "Troe" expression for termolecular reactions, these parameters accurately reproduce the current data in the fall-off regime and also capture literature rate coefficients at extrapolated temperatures. The presence of water vapor was found to enhance the rate coefficients of the title reaction significantly. The low-pressure limiting rate coefficient in H2O bath gas is a factor 5-6 larger than in N2, at room temperature (k1,0H2O = 4.55 × 10-30 (T/300 K)-4.85 cm6 molecule-2 s-1) indicating that H2O is much more efficient in quenching the association complex HONO* through collisional energy transfer. Based on measurements in N2-H2O mixtures, a parametrization of k1 including both N2 and H2O as third-body quenchers was derived. Neglecting the effect of H2O results, e.g., in an underestimation of k1 by >10% in the tropical boundary layer.

10.
J Pediatr Surg ; 57(6): 1013-1017, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35307194

RESUMO

BACKGROUND: Pulmonary nodules that are deep within lung parenchyma and/or small in size can be challenging to localize for biopsy. This study describes current trends in performance of image-guided localization techniques for pulmonary nodules in pediatric patients. METHODS: A retrospective review was performed on patients < 21 years of age undergoing localization of pulmonary nodules at 15 institutions. Localization and resection success, time in interventional radiology (IR), operating room (OR) and total anesthesia time, complications, and technical problems were compared between techniques. RESULTS: 225 patients were included with an average of 1.3 lesions (range 1-5). Median nodule size and depth were 4 mm (range 0-30) and 5.4 mm (0-61), respectively. The most common localization techniques were: wire + methylene blue dye (MBD) (28%), MBD only (25%), wire only (14%), technetium-99 only (11%), coil + MBD (7%) and coil only (5%). Localization technique was associated with institution (p < 0.01); technique and institution were significantly associated with mean IR, OR, and anesthesia time (all p < 0.05). Comparing techniques, there was no difference in successful IR localization (range 92-100%, p = 0.75), successful resection (94-100%, p = 0.98), IR technical problems (p = 0.22), or operative complications (p = 0.16). CONCLUSIONS: Many IR localization techniques for small pulmonary nodules in children can be successful, but there is wide variability in application by institution and in procedure time. LEVEL OF EVIDENCE: Retrospective review, Level 3.


Assuntos
Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Nódulo Pulmonar Solitário , Oncologia Cirúrgica , Criança , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Azul de Metileno , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/cirurgia , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Torácica Vídeoassistida/métodos , Tomografia Computadorizada por Raios X/métodos
11.
A A Pract ; 16(3): e01576, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35324512

RESUMO

Headache after subarachnoid hemorrhage and corresponding craniotomy with aneurysm clipping can be severe and difficult to treat. Currently accepted analgesic therapies are often ineffective at treating the pain without incurring unacceptable side effects. We present an innovative approach wherein intravenous lidocaine infusions were used to successfully treat 2 patients with hyperalgesia refractory to traditional analgesic therapies. Opioid consumption fell to zero for both patients during lidocaine infusions without lidocaine toxicity. Moreover, after discontinuation of lidocaine infusions, both patients reported good pain control using only standard oral medications.


Assuntos
Lidocaína , Hemorragia Subaracnóidea , Analgésicos Opioides/uso terapêutico , Cefaleia/tratamento farmacológico , Cefaleia/etiologia , Humanos , Dor/tratamento farmacológico , Hemorragia Subaracnóidea/complicações
12.
Health Commun ; 37(8): 1013-1021, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-33563035

RESUMO

The aim of the study was to examine the impact of supportive communication on acute physiological stress responses during weight-related conversations taking place throughout a couples' weight loss program. Participants were 47 married or cohabitating couples where each partner had a BMI of 25-40 kg/m2. Couples were randomized as a dyad into a traditional weight loss program or a program that also included training in providing support to one's partner throughout the weight loss process. Structured conversations between partners about weight management were videotaped at baseline and 6 months. Participants provided saliva samples before and after the conversations, which were assayed for cortisol and salivary alpha-amylase (sAA) to determine physiological stress and anxiety responses to conversations about weight. The results indicated that receiving support from one's partner when discussing weight-related issues was associated with greater physiological stress, as indicated by higher cortisol and sAA levels, whereas providing support to one's partner was associated with lower cortisol levels and higher sAA levels. The findings suggest that receiving support is not a universally positive experience, especially for populations facing health issues. The mixed findings for support provision align with previous studies identifying a negative association between affectionate communication and cortisol levels, as well as a positive association between sAA and anxiety and emotional arousal. The findings and their implications for understanding the physiological correlates of couples' conversations about weight are discussed.


Assuntos
Hidrocortisona , Sobrepeso , Comunicação , Humanos , Obesidade , Saliva , Estresse Fisiológico , Estresse Psicológico/psicologia
13.
Ann Behav Med ; 56(4): 347-356, 2022 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-34596660

RESUMO

BACKGROUND: COVID-19 vaccine uptake is an urgent public health priority. PURPOSE: To identify psychosocial determinants (attitudes, normative pressure, and perceived behavioral control) of COVID-19 vaccination intentions for U.S. White, Black, and Hispanic adults, and how COVID-19 misperceptions, beliefs about the value of science, and perceived media bias relate to these determinants. METHODS: Longitudinal online survey using two national samples (18-49 years old/50 years and older), each stratified by racial/ethnic group (n = 3,190). Data were collected in October/November 2020 and were weighted by race group to be representative. RESULTS: Path analyses showed that more positive attitudes about getting vaccinated predict intention across age and racial/ethnic groups, but normative pressure is relevant among older adults only. Belief in the value of science was positively associated with most determinants across all groups, however the association of COVID-19 misperceptions and perceived media bias with the determinants varied by age group. CONCLUSIONS: Messages that emphasize attitudes toward vaccination can be targeted to all age and racial/ethnic groups, and positive attitudes are universally related to a belief in the value of science. The varying role of normative pressure poses messages design challenges to increase vaccination acceptance.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Adolescente , Adulto , Idoso , COVID-19/prevenção & controle , Hispânico ou Latino , Humanos , Intenção , Pessoa de Meia-Idade , Vacinação/psicologia , Adulto Jovem
14.
Transl Anim Sci ; 5(3): txab126, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34430801

RESUMO

Information on body weight and average daily gain (ADG) of growing animals is key not only to monitoring performance, but also for use in genetic evaluations in the pursuit of achieving sustainable genetic gain. Accurate calculation of ADG, however, requires serial measures of body weight over at least 70 days. This can be resource intensive and thus alternative approaches to predicting individual animal ADG warrant investigation. One such approach is the use of continuously collected individual animal partial body weights. The objective of the present study was to determine the utility of partial body weights in predicting both body weight and ADG; a secondary objective was to deduce the appropriate length of test to determine ADG from partial body weight records. The dataset used consisted of partial body weights, predicted body weights and recorded body weights recorded for 8,972 growing cattle from a range of different breed types in 35 contemporary groups. The relationships among partial body weight, predicted body weight and recorded body weight at the beginning and end of the performance test were determined and calculated ADG per animal from each body weight measure were also compared. On average, partial body weight explained 90.7 ± 2.0% of the variation in recorded body weight at the beginning of the postweaning gain test and 87.9 ± 2.9% of the variation in recorded body weight at its end. The GrowSafe proprietary algorithm to predict body weight from the partial body weight strengthened these coefficients of determination to 95.1 ± 0.9% and 94.9 ± 0.8%, respectively. The ADG calculated from the partial body weight or from the predicted body weight were very strongly correlated (r = 0.95); correlations between these ADG values with those calculated from the recorded body weights were weaker at 0.81 and 0.78, respectively. For some applications, ADG may be measured with sufficient accuracy with a test period of 50 days using partial body weights. The intended inference space is to individual trials which have been represented in this study by contemporary groups of growing cattle from different genotypes.

16.
Med J (Ft Sam Houst Tex) ; (PB 8-21-01/02/03): 108-110, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33666921

RESUMO

COVID-19, a highly infectious virus, presents self-evident problems with regards to aeromedical transportation. Droplet size, proximity of caregiver from the patient, severity of upper and lower respiratory symptoms, personal protective equipment (PPE) and turbulence of airflow are factors which may influence the transmission of any biological agent aboard an air transport platform. Given the relatively confined space of rotary-wing MEDEVAC helicopters and the lack of structural barriers between flight crew and passengers, transmission risk is high, particularly when close contact under these conditions last beyond 15 minutes.1 Some authorities strongly recommend against the rotary-wing evacuation of COVID-19 patients when ground or fixed-wing transport is available due to the high risk of transmission.2,3.


Assuntos
Resgate Aéreo/organização & administração , COVID-19/prevenção & controle , COVID-19/transmissão , Controle de Infecções/organização & administração , Humanos , Equipamento de Proteção Individual , Guias de Prática Clínica como Assunto
17.
Phys Chem Chem Phys ; 23(11): 6397-6407, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33704308

RESUMO

We have developed and tested two-photon excited fragment spectroscopy (TPEFS) for detecting HNO3 in pulsed laser photolysis kinetic experiments. Dispersed (220-330 nm) and time-dependent emission at (310 ± 5) nm following the 193 nm excitation of HNO3 in N2, air and He was recorded and analysed to characterise the OH(A2Σ) and NO(A2Σ+) electronic excited states involved. The limit of detection for HNO3 using TPEFS was ∼5 × 109 molecule cm-3 (at 60 torr N2 and 180 µs integration time). Detection of HNO3 using the emission at (310 ± 5 nm) was orders of magnitude more sensitive than detection of NO and NO2, especially in the presence of O2 which quenches NO(A2Σ+) more efficiently than OH(A2Σ). While H2O2 (and possibly HO2) could also be detected by 193 nm TPEFS, the relative sensitivity (compared to HNO3) was very low. The viability of real-time TPEFS detection of HNO3 using emission at (310 ± 5) nm was demonstrated by monitoring HNO3 formation in the reaction of OH + NO2 and deriving the rate coefficient, k2. The value of k2 obtained at 293 K and pressures of 50-200 torr is entirely consistent with that obtained by simultaneously measuring the OH decay and is in very good agreement with the most recent literature values.

18.
Aerosp Med Hum Perform ; 92(4): 274-280, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33752791

RESUMO

INTRODUCTION: In response to the urgent need for safe aircrew respiratory protection due to the COVID-19 pandemic, three small descriptive evaluations were conducted with aircrew and air traffic controllers (ATC) that assessed the impact of mask use on safety and performance onboard rotary wing aircraft.METHODS: A series of evaluations assessed aircrew performance using the 3MTM Model 1860 N95 respiratory protection mask, two aviation-specific cloth mask prototypes, and a commercial off-the-shelf aviation-specific cloth mask. The series of evaluations included different sets of subjects consisting of up to five Black Hawk helicopter aircrew members, air traffic control (ATC), and 12 CH-47 aircrew members. The Modified Rhyme Test was used to measure speech intelligibility and was administered in the UH-60 among crewmembers of the same aircraft, between pilots of different aircraft, and between the pilots and ATC. Measures of workload, usability, comfort, and pulse oximetry were also administered.RESULTS: Results from the Modified Rhyme Test indicated that all subjects scored greater than 80% accuracy given the proper microphone positioning relative to the mask. With respect to workload, NASA-TLX total scores for the perform radio communications task was 50.83.DISCUSSION: Despite an elevated perceived degree of workload on the communications flight task, results from the speech intelligibility test indicated that performance was maintained within the acceptable range as defined by MIL-STD-1474E, Design Criteria Standard Noise Limit. This abbreviated evaluation suggests that the face masks tested are safe for use by helicopter aircrew under the conditions tested.Cave KM, Kelley AM, Feltman KA, Gerstner JA, Stewart JL, Crowley JS. Aircrew performance and safety while using protective masks in response to coronavirus disease. Aerosp Med Hum Perform. 2021; 92(4):274280.


Assuntos
Aeronaves , Máscaras , Testes de Discriminação da Fala , Inteligibilidade da Fala , Humanos , Rádio , Segurança , Carga de Trabalho
19.
J Anim Sci ; 99(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33738468

RESUMO

Poor teat and udder structure, frequently associated with older cows, impact cow production and health as well as calf morbidity and mortality. However, producer culling, for reasons including age, production, feed availability, and beef markets, creates a bias in teat (TS) and udder scores (US) assessed and submitted to the Canadian Angus Association for genetic evaluations toward improved mammary structure. In addition, due to the infancy of the reporting program, repeated scores are rare. Prior to the adoption of genetic evaluations for TS and US in Canadian Angus cattle, it is imperative to verify that TS and US from young cows are the same traits as TS and US estimated on mature cows. Genetic parameters for TS and US from all cows (n = 4,192) and then from young cows (parities 1 and 2) and from mature cows (parity ≥ 4) were estimated using a single-trait animal model. Genetic correlations for the traits between the two cow age groups were estimated using a two-trait animal model. Estimates of heritability (posterior SD [PSD]) were 0.32 (0.07) and 0.45 (0.07) for young TS and US and 0.27 (0.07) and 0.31 (0.07) for mature TS and US, respectively. Genetic correlation (PSD) between the young and mature traits was 0.87 (0.13) for TS and 0.40 (0.17) for US. Genome-wide association studies were used to further explore the genetic and biological commonalities and differences between the two groups. Although there were no genes in common for the two USs, 12 genes overlapped for TS in the two cow age groups. Interestingly, there were also 23 genes in common between TS and US in mature cows. Based on these findings, it is recommended that producers collect TS and US on their cow herd annually.


Assuntos
Estudo de Associação Genômica Ampla , Glândulas Mamárias Animais , Animais , Canadá , Bovinos/genética , Feminino , Genoma , Estudo de Associação Genômica Ampla/veterinária , Genômica , Lactação , Gravidez
20.
J Anim Breed Genet ; 138(3): 314-325, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33599015

RESUMO

The Canadian Angus Association recently developed genetic evaluations for teat and udder structure, which impact efficiencies, and animal health and welfare. Genetic selection tools are most effective incorporated into economic selection indexes. An important factor in the development of economic indexes is the estimation of the economic value and discounted gene expression coefficients, and thereby the economic weight, of each trait. Traditional estimation methods, interrogation of previous studies quantifying the impact of the traits and bioeconomic modelling, were reinforced using producer surveys that employed pairwise ranking methods. Estimates of discounted genetic expression coefficients, economic value and economic weight for teat and udder score in Canadian Angus cattle were 0.31 per sire, $52.47, and $16.91 per score change on a per calf born basis, respectively, indicating that functional traits such as teat and udder structure have a significant impact on profitability and should be included in genetic selection programmes. Limitations in previous studies illustrate the need for longitudinal studies on traits that impact efficiencies and animal health and welfare.


Assuntos
Bovinos/genética , Animais , Peso Corporal , Canadá , Feminino , Lactação , Glândulas Mamárias Animais , Fenótipo
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