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The neonatal leptin surge is important for hypothalamic development, feed intake regulation, and long-term metabolic control. In sheep, the leptin surge is eliminated with maternal overnutrition and an elevated dam body condition score (BCS), but this has not been assessed in dairy cattle. The aim of this study was to characterize the neonatal profile of leptin, cortisol and other key metabolites in calves born to Holstein cows with a range of BCS. Dam BCS was determined 21 d before expected parturition. Blood was collected from calves within 4 h of birth (d 0), and on days 1, 3, 5, and 7. Serum was analyzed for concentrations of leptin, cortisol, blood urea nitrogen, β-hydroxybutyrate (BHB), free fatty acids (FFA), triglycerides, and total protein (TP). Statistical analysis was performed separately for calves sired by Holstein (HOL) or Angus (HOL-ANG) bulls. Leptin tended to decrease after birth in HOL calves, but there was no evidence of an association between leptin and BCS. For HOL calves, the cortisol level increased with an increasing dam BCS on day 0 only. Dam BCS was variably associated with the calf BHB and TP levels, depending on the sire breed and day of age. Further investigation is required to elucidate the impacts of maternal dietary and energy status during gestation on offspring metabolism and performance, in addition to the potential impact of the absence of a leptin surge on long-term feed intake regulation in dairy cattle. [ABSTRACT FROM AUTHOR]

Feeding rumen-protected choline (RPC) to late gestation dairy cows has potential to affect growth in offspring. The objective of this study was to evaluate the effects of in utero choline exposure on the growth, feed efficiency (FE), metabolism, and carcass quality of Angus × Holstein cattle. Multiparous Holstein cows pregnant with male (N = 17) or female (N = 30) Angus-sired calves were enrolled 21 d prepartum and randomly assigned to one of four dietary treatments varying in quantity and formulation of RPC. The treatments included a control with 0 g/d supplemental RPC (CTL), supplemental RPC fed at the recommended dose (RD) of 15 g/d from either an established RPC product (RPC1RD; ReaShure; Balchem Corp.) or choline ion from a concentrated RPC prototype (RPC2RD; Balchem Corp.), or a high dose (HD) of RPC2 fed at 22 g/d (RPC2HD). From 2 to 6 mo of age, calves were group housed and offered 2.3 kg grain/hd/d (42% CP) with ad libitum grass hay, and stepped up to a complete finishing diet by 7 mo (12.0% CP; 1.34 Mcal/kg NEg). Weight and height were measured monthly. Animal FE was measured in individual pens for 35 d at 8 mo. Feed intake was measured daily, and blood was obtained on day 18 during the FE period. Afterwards, cattle were group housed and offered a free-choice finishing diet until slaughter, where carcass yield and quality characteristics were measured. Mixed models were used in PROC MIXED (SAS, 9.4) with the fixed effects of treatment, sex, time, their interactions, and the random effect of calf. Month was the repeated measure, and preplanned contrasts were used. Blood and FE data were analyzed with the fixed effect of dam choline treatment, calf sex, and the interaction. Increasing dose of RPC tended to increase weight over the entire study period. Feeding any RPC increased hip and wither height compared with CTL, and increasing RPC dose linearly increased hip and wither height. Treatment and sex interacted on DMI whereby increasing RPC intake linearly increased DMI for males but not females. Compared with control, feeding any RPC decreased plasma insulin, glucose, and an insulin sensitivity index (RQUICKI). In utero choline exposure increased kidney–pelvic–heart fat and marbling score. Mechanisms of action for intrauterine choline exposure on offspring growth, metabolism, and carcass characteristics should be explored as they have direct implications for profitability for cattle growers and feeders. [ABSTRACT FROM AUTHOR]

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Lead poisoning, mainly through incidental ingestion of lead ammunition in carcasses, is a threat to scavenging and predatory bird species worldwide. In Australia, shooting for animal control is widespread, and a range of native scavenging species are susceptible to lead exposure. However, the prevalence of lead exposure in Australia's scavenging and predatory birds is largely unknown. We evaluated the degree to which the Tasmanian wedge‐tailed eagle (Aquila audax fleayi), an endangered Australian raptor and facultative scavenger, showed evidence of lead exposure. We detected lead in 100% of femur and liver tissues of 109 eagle carcasses opportunistically collected throughout Tasmania between 1996 and 2018. Concentrations were elevated in 10% of 106 liver (>6 mg/kg dry wt) and 4% of 108 femur (>10 mg/kg dry wt) samples. We also detected lead in 96% of blood samples taken from 24 live nestlings, with 8% at elevated concentrations (>10 μg/dL). Of the liver samples with elevated lead, 73% had lead207/206 isotope ratios within the published range of lead‐based bullets available in Tasmania. These first comprehensive data on lead exposure of an Australian raptor are comparable to those for raptor studies elsewhere that identify lead‐based ammunition exposure as a conservation threat. Our findings highlight the importance of further research and efforts to address lead contamination throughout the Tasmanian ecosystem and in other Australian regions. Environ Toxicol Chem 2021;40:219–230. © 2020 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by US Government employees and their work is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

Abstract: Monitoring the response of wild mammal populations to threatening processes is fundamental to effective conservation management. This is especially true for infectious diseases, which may have dynamic and therefore unpredictable interactions with their host. We investigate the long‐term impact of a transmissible cancer, devil facial tumour disease (DFTD), on the endemic Tasmanian devil. We analyse trends in devil spotlight counts and density across the area impacted by the disease. We investigate the demographic parameters which might be driving these trends, and use spatial capture‐recapture models to examine whether DFTD has affected home range size. We found that devils have declined by an average of 77% in areas affected by DFTD, and that there is a congruent trend of ongoing small decline in spotlight counts and density estimates. Despite this, devils have persisted to date within each of nine monitoring sites. One site is showing as yet unexplained small increases in density 8–10 years after the emergence of DFTD. We also found the prevalence of DFTD has not abated despite large declines in density and that diseased sites continue to be dominated by young devils. The long‐term impact of the disease has been partially offset by increased fecundity in the form of precocial breeding in 1‐year‐old females, and more pouch young per female in diseased sites. The lower densities resulting from DFTD did not affect home range size. Synthesis and applications. Transmission of devil facial tumour disease continues despite large declines in devil density over multiple generations. Plasticity in life history traits has ameliorated the impact of devil facial tumour disease, however broad‐scale trends in density show ongoing decline. In light of this, devil facial tumour disease and the impact of stochastic events on the reduced densities wrought by the disease, continue to threaten devils. In the absence of methods to manage disease in wild populations, we advocate managing the low population densities resulting from disease rather than disease per se. [ABSTRACT FROM AUTHOR]

Introduction. Since the inception of emergency medical services (EMS), individuals have assumed the role of 'training officer' without a clear and concise description of the responsibilities inherent in this position. Furthermore, EMS system leaders rely heavily on these individuals to implement changes within an EMS system and to ensure the competency of practicing out-of-hospital professionals. The limited understanding of and research in training officer roles highlight the need for study in this area. Objectives. Specific objectives of our study were to describe demographic and work-life characteristics of training officers, estimate the number of hours spent on specific training officer tasks in a typical week, and determine methods of training officer appointment and education received after appointment. Methods. This was a questionnaire-based cross-sectional census analysis of all training officers in the National Registry of Emergency Medical Technicians (NREMT) database. This questionnaire contained items related to demographics, work-life characteristics, and specific roles and responsibilities of training officers. Descriptive statistics, chi-square, and Mann-Whitney U tests were utilized to assess specific differences among training officers. Results. Over 2,500 individuals responded to this questionnaire (2,528/4,956). The majority of the respondents were male (79.0%), held a full-time salaried position (64.9%), and were of nonminority status (93.4%). Individuals reported an overall median number of years worked in EMS of 19.0 (standard deviation [SD] = 8.7, range = 0-45) and a median of 4.0 years of serving as a training officer (SD = 5.1, range = 0-33), and planned to serve as a training officer for a median of 10.0 years (SD = 7.6, range = 0-50). The highest median numbers of hours spent on specific training officer tasks in a typical week were for providing patient care (median = 8.0, SD = 18.1); developing, delivering, and accounting for continuing education (median = 5.0, SD = 9.8); department administration (median = 5.0, SD = 12.8); and performing run reviews (median = 3.0, SD = 6.4). Conclusion. The role of the training officer in ensuring the continued competence of the EMS professional has not been delineated in this paper, and future efforts should seek to answer this research question. Key words: emergency medical services; training officers; system administration [ABSTRACT FROM AUTHOR]

Diisocyanates are used to produce a wide variety of polyurethane products; they are also recognized as an important cause of occupational asthma. Their chemical reactivity presents challenges to toxicologists and clinicians alike seeking to understand the mechanisms underlying diisocyanate asthma. In this article, we review the literature on immunoassay detection of IgE and IgG binding to diisocyanate-protein conjugates and assess the utility of such testing as a diagnostic tool and exposure indicator. Data from 29 studies of occupational exposure to diisocyanates revealed considerable variability in assay methodology and heterogeneity in the prevalence of positive antibody responses across laboratories. In studies that included both confirmed diisocyanate asthma subjects and exposed nonasthmatics, positive IgE responses identified cases with low sensitivity (18-27%), but high specificity (96-98%). Detection of IgG binding to diisocyanate conjugates is an indirect, qualitative indicator of disease status and past diisocyanate exposure. The utility of these assays is limited, however, due to a lack of (1) method standardization, (2) population norms to guide interpretation of results, and (3) demonstration that the assays improve either on disease prediction or on exposure confirmation beyond that of other indicators. Sources of assay heterogeneity are discussed and suggestions are offered for improving test performance and interpretability. [ABSTRACT FROM AUTHOR]

Biomarkers are very useful tools when the metabolic fate of the compound or the etiology of a resultant disease is completely understood. They may contribute to confusion if it is not possible to distinguish between markers of exposure and markers of disease. Such is the case for biomarkers used in the assessment of diisocyanate exposure. Biomarkers for diisocyanate exposure result from both direct and indirect effects. Molecules such as hemoglobin, albumin, tubulin, glutathione, and laminin have been implicated as having been directly modified as a result of exposure to toluene diisocyanate (TDI). In addition, indirect biomarkers have included profiles of molecules such as antibodies, cytokines, cell accumulation or proliferation, and markers of oxidative stress. While a brief presentation of each of these markers is provided here, the focus is primarily on immunological markers as an example of the difficulties with using biomarkers in assessing diisocyanate exposure in general, and TDI specifically. Compiled data will be used to demonstrate where gaps exist in our understanding of how the results of measured biomarkers are used with regard to isocyanate exposure, and whether it may be possible to develop these tools to define thresholds between exposure and disease. Issues addressed include whether the marker represents a measure of exposure or disease, whether the methods are sufficiently uniform between labs to be able to compare between studies, and whether the ambiguities are the result of the complexity of the isocyanate reactivity in the biological system, or our inability to accurately measure the end point of the reactions. [ABSTRACT FROM AUTHOR]

The β-function is calculated for an SU(N) Yang-Mills theory from an ansatz for the vacuum wavefunctional. Direct comparison is made with the results of calculations of the β-function of QCD. In both cases the theories are asymptotically free, the only difference being in the numerical coefficient of the β-function, which is found to be -4 from the ansatz and -4 + ⅓ from other QCD calculations. This is because, due to the constraint of Gauss' law applied to the wavefunctional, some interactions between gluons (which contribute the ⅓) are omitted. The renormalisation procedure is understood in terms of "tadpole" and "horseshoe" Feynman diagrams which must be interpreted with a nonlocal propagator. [ABSTRACT FROM AUTHOR]

Sixty-eight adults and nine children infected with human immunodeficiency virus type 1 (HIV-1) were evaluated consecutively for the presence and amount of cell-free infectious virus in their plasma. Viremia was detected in 18 of 68 adults and in five of nine children; titers ranged from 10 to 100,000,000 TCID/ml plasma. Among the adults, none of 19 asymptomatic patients, 4 of 34 AIDS-related complex patients, and 14 of 15 AIDS patients had cell-free infectious virus in their plasma. None of 35 adult subjects with CD4+ lymphocyte counts >400/mm3 were viremic, whereas 3 of 17 with 200–400 CD4+ lymphocytes/mm3 and 15 of 16 individuals with <200 CD4+ lymphocytes/mm3 were plasma viremic. In contrast to adults, each of five children infected with HIV-1 in utero or during the perinatal period were plasma viremic regardless of their CD4+ lymphocyte counts (range, 42-2227/mm3), duration of infection, or clinical stage; however, children infected by HIV-1 at older ages were less frequently plasma viremic. Therapy with zidovudine led to a 10- to 106-fold decline in plasma HIV-1 TCID in all eight subjects studied before and after treatment. [ABSTRACT FROM PUBLISHER]

Plasma lysozyme was measured in turkeys with experimental fowl cholera produced by either of two serotypes of Pasteurella multocida. Lysozyme was not detected in preexposure plasma, whereas plasma sampled when turkeys were terminally bacteremic contained 7.0–7.5 μg of lysozyme/ml. Plasma lysozyme was measured in turkeys inoculated intravenously with P. multocida lipopolysaccharide (LPS). Turkeys inoculated with 10 μg of LPS produced plasma lysozyme detectable for 2 hr after inoculation; those inoculated with 500 μg of LPS produced plasma lysozyme detectable for at least 6 hr after inoculation. Egg-white lysozyme, equivalent in concentration to the plasma lysozyme detected in bacteremic turkeys, was active upon young cultures of P. multocida and increased the degree of lysis of P. multocida cells treated with deoxycholate. Lysozyme, ethylenediaminetetraacetate, and deoxycholate in combination produced the highest degree of lysis of P. multocida cells. [ABSTRACT FROM PUBLISHER]

Through the use of radioactively labeled methyl isocyanate (MIC), the deposition, penetration, and clearance of this highly reactive compound in the airway at the tissue and cellular levels have been directly examined. Guinea pigs were exposed to C-MIC vapors at concentrations ranging from 0.38 to 15.2 ppm for periods of 1–6 hr. Solubilization of tissues from these animals showed the airway tissues to have the highest level of radioactivity. In the nasal region, C deposition, as monitored by histoautoradiography, was limited to the epithelial layer, was related to dose, and was dependent on the specific epithelial cell type. The squamous epithelium was minimally labeled on the surface and the label did not penetrate the cell layer. However, radioactivity was detected throughout the entire nasal respiratory epithelial layer. The lack of nasal deposition in tracheotomized animals demonstrated that the C accumulation at this site was due to the scrubbing action of the nasal region with no contribution from blood recirculation. Cellular localization in the tracheobronchial region showed epithelial and subepithelial deposition in a dose-dependent manner with accumulation of the label at the subepithelial region. Radioactivity penetrated to the level of the terminal bronchiole but was not detected in the alveolar region. The persistence of airway radioactivity over the 48-hr postexposure period monitored suggests the covalent modification of airway macromolecules. Despite its broad specificity and high reactivity, MIC undergoes selective reactions in the airways which are dependent on respiratory region and cell type. [ABSTRACT FROM PUBLISHER]

Effects of Inhaled Hexamethylene Diisocyanate (HDI) on Guinea Pig Cholinesterases. KAROL, M. H., HANSEN, G. A., AND BROWN, W. E. (1984). . 4, 284–287. Hexamethylene diisocyanate, HDI, a starting material in the production of many polyurethane products, was found to inhibit stoichiometrically mammalian and electric eel cholinesterases in an system (W. E. Brown, A. H. Green, M. H. Karol, and Y. Alarie, 1982, . 62, 45–52). The current study examined effects on guinea pig cholinesterases resulting from inhalation of HDI. Guinea pigs were exposed to atmospheres of 0.5, 1.8, or 4.0 ppm HDI (ceiling value = 0.02 ppm) for up to 6 hr. Blood samples were drawn prior to exposure and at specified times during exposure. No inhibition of serum cholinesterase was detected following exposure to 0.5 ppm HDI for 6 hr, to 1.8 ppm HDI for 2 hr, or to 4.0 ppm HDI for 3 hr. Similarly, no inhibition was detected when erythrocytes from each blood sample were assayed for acetylcholinesterase activity. Last, animals were sacrificed and cholinesterase activity determined in bronchial lavage fluid. Enzyme levels of HDI-exposed animals were not significantly different (P > 0.05) from those of control animals exposed to water vapor. In conclusion, although experiments had demonstrated potent anticholinesterase activity by HDI, inhalation exposure of guinea pigs to HDI at concentrations 25–200 times above the recommended (ACGIH) ceiling value did not produce measurable inhibition of cholinesterase activity. [ABSTRACT FROM PUBLISHER]

Do discipline issues differ significantly now from ten years ago? Two hundred and nineteen teachers share their views. [ABSTRACT FROM PUBLISHER]

A survey that adds new dimension to understanding current discipline policies/practices in the public schools [ABSTRACT FROM PUBLISHER]

A look at Lee Canter's approach to structuring the classroom for behavioral controls [ABSTRACT FROM PUBLISHER]

Discusses the role of race in the use of praise and criticism by classroom teachers according to a study. Praise-criticism ratio in a class where teachers and students are of different race; Pupil responses in a mixed-race classroom; Categories of praise and criticism used in the study, such as designation of student performance as acceptable or unacceptable and use of sarcasm among others.