Applicability of Ammonia Sensors for Controlling Environmental Parameters in Accommodations for Lamb Fattening

Electrochemical ammonia sensors were used to analyse the existing relationship between the ammonia concentration and ambient levels of both temperature and relative humidity in commercial lamb fattening housing equipped with mechanical ventilation and straw-bedded pens. In the first stage of the experiment, sensors were placed over straw beds covered in lamb urine and analysed under laboratory conditions in order to determine ammonia emission evolution over time; three control temperatures (25, 35, and 50 degrees C) were used. A HOBO H8 temperature and relative humidity logger and a Drager NH3LC-6809680 electrochemical ammonia sensor placed in a Drager Polytron 7000 gas detector were utilized as sensors. A positive correlation was established between both ammonia emission time and emitted amount with temperature. Additionally, tests were performed in a commercial lamb housing to determine ammonia concentration variation with respect to height from the ground; three ammonia sensors placed at 50, 90, and 135 cm above the ground were used simultaneously. The ammonia concentration significantly decreased as height increased. A 90 cm height was selected, and three ammonia probes were placed in three different pens inside the livestock housing, along with temperature and relative humidity sensors; four different housing ventilation rates were then tested under real conditions over a time period of 4 months. An adjustment polynomial equation between the housing ambient temperature and the ammonia concentration was obtained with R-2 = 0.632. In conclusion, a relationship can be established between temperature and ammonia concentration in commercial lamb housing under certain handling conditions, which in turn allows for estimating the ammonia concentration adequately based on the ambient internal temperature

Occupational characteristics associated with SARS-CoV-2 infection in the UK Biobank during August-November 2020: A cohort study

BACKGROUND: Occupational exposures may play a key role in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection risk. We used a job-exposure matrix linked to the UK Biobank to measure occupational characteristics and estimate associations with a positive SARS-CoV-2 test. METHODS: People reporting job titles at their baseline interview in England who were \u3c 65 years of age in 2020 were included. Healthcare workers were excluded because of differential access to testing. Jobs were linked to the US Occupational Information Network (O*NET) job exposure matrix. O*NET-based scores were examined for occupational physical proximity, exposure to diseases/infection, working outdoors exposed to weather, and working outdoors under cover (score range = 1-5). Jobs were classified as remote work using two algorithms. SARS-CoV-2 test results were evaluated between August 5th-November 10th, 2020, when the UK was released from lockdown. Cox regression was used to calculate adjusted hazard ratios (aHRs), accounting for age, sex, race, education, neighborhood deprivation, assessment center, household size, and income. RESULTS: We included 115,451 people with job titles, of whom 1746 tested positive for SARS-CoV-2. A one-point increase in physical proximity score was associated with 1.14 times higher risk of SARS-CoV-2 (95%CI = 1.05-1.24). A one-point increase in the exposure to diseases/infections score was associated with 1.09 times higher risk of SARS-CoV-2 (95%CI = 1.02-1.16). People reporting jobs that could not be done remotely had higher risk of SARS-CoV-2 regardless of the classification algorithm used (aHRs = 1.17 and 1.20). Outdoors work showed an association with SARS-CoV-2 (exposed to weather aHR = 1.06, 95%CI = 1.01-1.11; under cover aHR = 1.08, 95%CI = 1.00-1.17), but these associations were not significant after accounting for whether work could be done remotely. CONCLUSION: People in occupations that were not amenable to remote work, required closer physical proximity, and required more general exposure to diseases/infection had higher risk of a positive SARS-CoV-2 test. These findings provide additional evidence that coronavirus disease 2019 (COVID-19) is an occupational disease, even outside of the healthcare setting, and indicate that strategies for mitigating transmission in in-person work settings will remain important

Toxicity of Volatile Methylated Species of Bismuth, Arsenic, Tin, and Mercury in Mammalian Cells In Vitro

The biochemical transformation of mercury, tin, arsenic and bismuth through formation of volatile alkylated species performs a fundamental role in determining the environmental processing of these elements. While the toxicity of inorganic forms of most of these compounds are well documented (e.g., arsenic, mercury) and some of them are of relatively low toxicity (e.g., tin, bismuth), the more lipid-soluble organometals can be highly toxic. In the present study we investigated the cyto- and genotoxicity of five volatile metal(loid) compounds: trimethylbismuth, dimethylarsenic iodide, trimethylarsine, tetramethyltin, and dimethylmercury. As far as we know, this is the first study investigating the toxicity of volatile metal(loid) compounds in vitro. Our results showed that dimethylmercury was most toxic to all three used cell lines (CHO-9 cells, CaCo, Hep-G2) followed by dimethylarsenic iodide. Tetramethyltin was the least toxic compound; however, the toxicity was also dependend upon the cell type. Human colon cells (CaCo) were most susceptible to the toxicity of the volatile compounds compared to the other cell lines. We conclude from our study that volatile metal(loid) compounds can be toxic to mammalian cells already at very low concentrations but the toxicity depends upon the metal(loid) species and the exposed cell type

Determination of the Acceleration Region Size in a Loop-structured Solar Flare

In order to study the acceleration and propagation of bremsstrahlung-producing electrons in solar flares, we analyze the evolution of the flare loop size with respect to energy at a variety of times. A GOES M3.7 loop-structured flare starting around 23:55 on 2002 April 14 is studied in detail using \textit{Ramaty High Energy Solar Spectroscopic Imager} (\textit{RHESSI}) observations. We construct photon and mean-electron-flux maps in 2-keV energy bins by processing observationally-deduced photon and electron visibilities, respectively, through several image-processing methods: a visibility-based forward-fit (FWD) algorithm, a maximum entropy (MEM) procedure and the uv-smooth (UVS) approach. We estimate the sizes of elongated flares (i.e., the length and width of flaring loops) by calculating the second normalized moments of the intensity in any given map. Employing a collisional model with an extended acceleration region, we fit the loop lengths as a function of energy in both the photon and electron domains. The resulting fitting parameters allow us to estimate the extent of the acceleration region which is between $\sim 13 \rm{arcsec}$ and $\sim 19 \rm{arcsec}$. Both forward-fit and uv-smooth algorithms provide substantially similar results with a systematically better fit in the electron domain.The consistency of the estimates from these methods provides strong support that the model can reliably determine geometric parameters of the acceleration region. The acceleration region is estimated to be a substantial fraction ($\sim 1/2$) of the loop extent, indicating that this dense flaring loop incorporates both acceleration and transport of electrons, with concurrent thick-target bremsstrahlung emission.Comment: 8 pages, 5 figures, accepted to Astronomy and Astrophysics journa

Influences on Care Preferences of Older People with Advanced Illness: A Systematic Review and Thematic Synthesis.

OBJECTIVES: To determine and explore the influences on care preferences of older people with advanced illness and integrate our results into a model to guide practice and research. DESIGN: Systematic review using Medline, Embase, PsychINFO, Web of Science, and OpenGrey databases from inception to February 2017 and reference and citation list searching. Included articles investigated influences on care preference using qualitative or quantitative methodology. Thematic synthesis of qualitative articles and narrative synthesis of quantitative articles were undertaken. SETTING: Hospital and community care settings. PARTICIPANTS: Older adults with advanced illness, including people with specific illnesses and markers of advanced disease, populations identified as in the last year of life, or individuals receiving palliative care (N = 15,164). MEASUREMENTS: The QualSys criteria were used to assess study quality. RESULTS: Of 12,142 search results, 57 articles were included. Family and care context, illness, and individual factors interact to influence care preferences. Support from and burden on family and loved ones were prominent influences on care preferences. Mechanisms by which preferences are influenced include the process of trading-off between competing priorities, making choices based on expected outcome, level of engagement, and individual ability to form and express preferences. CONCLUSION: Family is particularly important as an influence on care preferences, which are influenced by complex interaction of family, individual, and illness factors. To support preferences, clinicians should consider older people with illnesses and their families together as a unit of care.Cicely Saunders International Atlantic Philanthropies. Grant Number: 24610 Collaboration for Leadership in Applied Health Research and Care, South London National Institute for Health Research (NIHR) King's Health Partners St. George's University London St George's Healthcare National Health Service (NHS) Trus

Interval Management: Development and Implementation of an Airborne Spacing Concept

Interval Management is a suite of ADS-B-enabled applications that allows the air traffic controller to instruct a flight crew to achieve and maintain a desired spacing relative to another aircraft. The flight crew, assisted by automation, manages the speed of their aircraft to deliver more precise inter-aircraft spacing than is otherwise possible, which increases traffic throughput at the same or higher levels of safety. Interval Management has evolved from a long history of research and is now seen as a core NextGen capability. With avionics standards recently published, completion of an Investment Analysis Readiness Decision by the FAA, and multiple flight tests planned, Interval Management will soon be part of everyday use in the National Airspace System. Second generation, Advanced Interval Management capabilities are being planned to provide a wider range of operations and improved performance and benefits. This paper briefly reviews the evolution of Interval Management and describes current development and deployment plans. It also reviews concepts under development as the next generation of applications

A reconnaissance survey of farmers’ awareness of hypomagnesaemic tetany in UK cattle and sheep farms

Hypomagnesaemic tetany (HypoMgT) in ruminants is a physiological disorder caused by inadequate intake or impaired absorption of magnesium (Mg) in the gut. If it is not detected and treated in time, HypoMgT can cause the death of the affected animal. A semi-structured questionnaire survey was conducted from July 2016–2017 to assess farmers’ awareness of HypoMgT in cattle and sheep in the UK. The questionnaire was distributed to farmers at farm business events and agricultural shows, and through a collaborative group of independent veterinary practices to their clients. Farmers were asked about (i) the incidence of presumed HypoMgT (PHT); (ii) their strategies to treat or prevent HypoMgT; (iii) mineral tests on animals, forage and soil, and (iv) farm enterprise type. A total of 285 responses were received from 82 cattle, 157 mixed cattle and sheep, and 46 sheep farmers, of whom 39% reported HypoMgT in their livestock, affecting 1–30 animals. Treatment and/or prevention against HypoMgT was reported by 96% respondents with PHT and 79% of those without. Mineral tests on animal, forage, and soil was conducted by 24%, 53%, and 66% of the respondents, respectively, regardless of PHT. There was a highly significant association between the use of interventions to tackle HypoMgT and the incidence of PHT (p < 0.01). The top three treatment/prevention strategies used were reported as being free access supplementation (149), in feed supplementation (59) and direct to animal treatments (drenches, boluses and injections) (45) although these did vary by farm type. Although some (9) reported using Mg-lime, no other pasture management interventions were reported (e.g., Mg-fertilisation or sward composition). Generally, the results indicate that UK farmers are aware of the risks of HypoMgT. A more integrated soil-forage-animal assessment may improve the effectiveness of tackling HypoMgT and help highlight the root causes of the problem

Relationship between clinical signs and postmortem test status in cattle experimentally infected with the bovine spongiform encephalopathy agent

<p>Abstract</p> <p>Background</p> <p>Various clinical protocols have been developed to aid in the clinical diagnosis of classical bovine spongiform encephalopathy (BSE), which is confirmed by postmortem examinations based on vacuolation and accumulation of disease-associated prion protein (PrP^d) in the brain. The present study investigated the occurrence and progression of sixty selected clinical signs and behaviour combinations in 513 experimentally exposed cattle subsequently categorised postmortem as confirmed or unconfirmed BSE cases. Appropriate undosed or saline inoculated controls were examined similarly and the data analysed to explore the possible occurrence of BSE-specific clinical expression in animals unconfirmed by postmortem examinations.</p> <p>Results</p> <p>Based on the display of selected behavioural, sensory and locomotor changes, 20 (67%) orally dosed and 17 (77%) intracerebrally inoculated pathologically confirmed BSE cases and 21 (13%) orally dosed and 18 (6%) intracerebrally inoculated but unconfirmed cases were considered clinical BSE suspects. None of 103 controls showed significant signs and were all negative on diagnostic postmortem examinations. Signs indicative of BSE suspects, particularly over-reactivity and ataxia, were more frequently displayed in confirmed cases with vacuolar changes in the brain. The display of several BSE-associated signs over time, including repeated startle responses and nervousness, was significantly more frequent in confirmed BSE cases compared to controls, but these two signs were also significantly more frequent in orally dosed cattle unconfirmed by postmortem examinations.</p> <p>Conclusions</p> <p>The findings confirm that in experimentally infected cattle clinical abnormalities indicative of BSE are accompanied by vacuolar changes and PrP^daccumulation in the brainstem. The presence of more frequently expressed signs in cases with vacuolar changes is consistent with this pathology representing a more advanced stage of disease. That BSE-like signs or sign combinations occur in inoculated animals that were not confirmed as BSE cases by postmortem examinations requires further study to investigate the potential causal relationship with prion disease.</p