2,429 research outputs found
ELISA detection of phenazepam, etizolam, pyrazolam, flubromazepam, diclazepam and delorazepam in blood using Immunalysis® benzodiazepine kit
Phenazepam and etizolam were the first uncontrolled benzodiazepines available for sale in the UK. Pyrazolam, flubromazepam and diclazepam are not used medicinally anywhere in the world; they are produced exclusively for the uncontrolled, recreational market. It is important to know whether potentially abused drugs like these can be detected in routine toxicological screening tests. The purpose of this study was to evaluate whether the Immunalysis® Benzodiazepines ELISA kit could detect phenazepam, etizolam, pyrazolam, flubromazepam, diclazepam and its metabolite delorazepam. Their cross-reactivity was assessed by comparing the absorbance of the drug with that of oxazepam, the reference standard. This study found that these uncontrolled benzodiazepines cross-react sufficiently to produce a positive result with the Immunalysis® Benzodiazepine ELISA kit. Cross-reactivity ranged from 79 to 107% for phenazepam, etizolam, pyrazolam, flubromazepam, diclazepam and delorazepam fortified into blood. The results show that it is possible to detect these newer benzodiazepines with traditional forensic toxicology laboratory tools and it is important to include these benzodiazepines in the confirmation tests
Peeling fingers in an elastic Hele-Shaw channel
Using experiments and a depth-averaged numerical model, we study
instabilities of two-phase flows in a Hele-Shaw channel with an elastic upper
boundary and a non-uniform cross-section prescribed by initial collapse.
Experimentally, we find increasingly complex and unsteady modes of air-finger
propagation as the dimensionless bubble speed, Ca, and level of collapse are
increased, including pointed fingers, indented fingers and the feathered modes
first identified by Cuttle et al.(J. Fluid Mech., vol. 886, 2020, A20).
By introducing a measure of the viscous contribution to finger propagation,
we identify a Ca threshold beyond which viscous forces are superseded by
elastic effects. Quantitative prediction of this transition between 'viscous'
and 'elastic' reopening regimes across levels of collapse establishes the
fidelity of the numerical model. In the viscous regime, we recover the
non-monotonic dependence on Ca of the finger pressure, which is characteristic
of benchtop models of airway reopening. To explore the elastic regime
numerically, we extend the depth-averaged model introduced by Fontana et al.
(J. Fluid Mech., vol. 916, 2021, A27) to include an artificial disjoining
pressure which prevents the unphysical self-intersection of the interface.
Using time simulations, we capture for the first time the majority of
experimental finger dynamics, including feathered modes. We show that these
disordered states continually evolve, with no evidence of convergence to steady
or periodic states. We find that the steady bifurcation structure
satisfactorily predicts the bubble pressure as a function of Ca, but that it
does not provide sufficient information to predict the transition to unsteady
dynamics which appears strongly nonlinear.Comment: 28 pages, 15 figure
Early childhood adversity and adolescent depression: the mediating role of continued stress
Background. While various conceptualizations of the link between childhood adversity and later depression have been offered, most have not accounted for the possibility that early adversity predicts continuing stress proximal to depression onset. Thus, the present study tested the possible mediating role of recent stress in the association between early adversity and depression in late adolescence
Baby Pigs Have a Sweet Tooth!
Early gains are the cheapest. And you can get faster early gains by feeding a good pig starter. In this article, the others tell how pig starters can be made more palatable and also what should go into a good pig starter
Genetic loci for ventricular dilatation in the LEW/Jms rat with fetal-onset hydrocephalus are influenced by gender and genetic background
BACKGROUND: The LEW/Jms rat strain has inherited hydrocephalus, with more males affected than females and an overall expression rate of 28%. This study aimed to determine chromosomal positions for genetic loci causing the hydrocephalus. METHODS: An F(1 )backcross was made to the parental LEW/Jms strain from a cross with non-hydrocephalic Fischer 344 rats. BC(1) rats were generated for two specific crosses: the first with a male LEW/Jms rat as parent and grandparent, [(F × L) × L], designated B group, and the second with a female LEW/Jms rat as the parent and grandparent [L × (L × F)], designated C group. All hydrocephalic and a similar number of non-hydrocephalic rats from these two groups were genotyped with microsatellite markers and the data was analyzed separately for each sex by MAPMAKER. RESULTS: The frequency of hydrocephalus was not significantly different between the two groups (18.2 and 19.9 %), but there was a significant excess of males in the B group. The mean severity of hydrocephalus, measured as the ventricle-to-brain width ratio, was ranked as B group < C group < LEW/Jms. For the both rat groups, there were several chromosomes that showed possible regions with association between phenotype and genotype significant at the 5% or 1.0% level, but none of these had significant LOD scores. For the C group with a female LEW/Jms parent, there was a fully significant locus on Chr2 with a LOD score of 3.81 that was associated almost exclusively with male rats. Both groups showed possible linkage on Chr17 and the data combined produced a LOD score of 2.71, between suggestive and full significance. This locus was largely associated with male rats with a LEW/Jms male parent. CONCLUSION: Phenotypic expression of hydrocephalus in Lew/Jms, although not X-linked, has a strong male bias. One, and possibly two chromosomal regions are associated with the hydrocephalus
Fetal liver blood flow distribution: role in human developmental strategy to prioritize fat deposition versus brain development
Among primates, human neonates have the largest brains but also the highest proportion of body fat. If placental nutrient supply is limited, the fetus faces a dilemma: should resources be allocated to brain growth, or to fat deposition for use as a potential postnatal energy reserve? We hypothesised that resolving this dilemma operates at the level of umbilical blood distribution entering the fetal liver. In 381 uncomplicated pregnancies in third trimester, we measured blood flow perfusing the fetal liver, or bypassing it via the ductus venosus to supply the brain and heart using ultrasound techniques. Across the range of fetal growth and independent of the mother's adiposity and parity, greater liver blood flow was associated with greater offspring fat mass measured by dual-energy X-ray absorptiometry, both in the infant at birth (r = 0.43, P<0.001) and at age 4 years (r = 0.16, P = 0.02). In contrast, smaller placentas less able to meet fetal demand for essential nutrients were associated with a brain-sparing flow pattern (r = 0.17, p = 0.02). This flow pattern was also associated with a higher degree of shunting through ductus venosus (P = 0.04). We propose that humans evolved a developmental strategy to prioritize nutrient allocation for prenatal fat deposition when the supply of conditionally essential nutrients requiring hepatic inter-conversion is limited, switching resource allocation to favour the brain if the supply of essential nutrients is limited. Facilitated placental transfer mechanisms for glucose and other nutrients evolved in environments less affluent than those now prevalent in developed populations, and we propose that in circumstances of maternal adiposity and nutrient excess these mechanisms now also lead to prenatal fat deposition. Prenatal developmental influences play important roles in the human propensity to deposit fa
Prenatal development is linked to bronchial reactivity: epidemiological and animal model evidence
Chronic cardiorespiratory disease is associated with low birthweight suggesting the importance of the developmental environment. Prenatal factors affecting fetal growth are believed important, but the underlying mechanisms are unknown. The influence of developmental programming on bronchial hyperreactivity is investigated in an animal model and evidence for comparable associations is sought in humans. Pregnant Wistar rats were fed either control or protein-restricted diets throughout pregnancy. Bronchoconstrictor responses were recorded from offspring bronchial segments. Morphometric analysis of paraffin-embedded lung sections was conducted. In a human mother-child cohort ultrasound measurements of fetal growth were related to bronchial hyperreactivity, measured at age six years using methacholine. Protein-restricted rats' offspring demonstrated greater bronchoconstriction than controls. Airway structure was not altered. Children with lesser abdominal circumference growth during 11-19 weeks' gestation had greater bronchial hyperreactivity than those with more rapid abdominal growth. Imbalanced maternal nutrition during pregnancy results in offspring bronchial hyperreactivity. Prenatal environmental influences might play a comparable role in humans
Where are the beachmasters? Unexpectedly weak polygyny among southern elephant seals on a South Shetland Island
Intraspecific variation in animal mating systems can have important implications for ecological, evolutionary and demographic processes in wild populations. For example, patterns of mating can impact social structure, dispersal, effective population size and inbreeding. However, few species have been studied in sufficient detail to elucidate mating system plasticity and its dependence on ecological and demographic factors. Southern elephant seals (Mirounga leonina) have long been regarded as a textbook example of a polygynous mating system, with dominant ‘beachmaster’ males controlling harems of up to several hundred females. However, behavioural and genetic studies have uncovered appreciable geographic variation in the strength of polygyny among elephant seal populations. We, therefore, used molecular parentage analysis to investigate patterns of parentage in a small satellite colony of elephant seals at the South Shetland Islands. We hypothesised that dominant males would be able to successfully monopolise the relatively small numbers of females present in the colony, leading to relatively high levels of polygyny. A total of 424 individuals (comprising 33 adult males, 101 adult females and 290 pups) sampled over 8 years were genotyped at 20 microsatellites and reproductive success was analysed by genetically assigning parents. Paternity could only be assigned to 31 pups (10.7%), despite our panel of genetic markers being highly informative and the genotyping error rate being very low. The strength of inferred polygyny was weak in comparison to previous genetic studies of the same species, with the most successful male fathering only seven pups over the entire course of our study. Our results show that, even in a species long regarded as a model for extreme polygyny, male reproductive skew can vary substantially among populations
Effect of nuclear motion on the critical nuclear charge for two-electron atoms
A variational method for calculating the critical nuclear charge, Zc, required for the binding of a nucleus to two electrons is reported. The method is very effective and performs well compared to the traditional variational principle for calculating energy. The critical nuclear charge, which corresponds to the minimum charge required for the atomic system to have at least one bound state, has been calculated for helium-like systems both with infinite and finite nuclear masses. The value of 0.911 028 2(3) is in very good agreement with recent values in the literature for two-electron atoms with an infinite nuclear mass. When nuclear motion is considered, the value for Zc varies from 0.911 030 3(2) for that with a nuclear mass of Ne (the largest heliogenic system considered) to 0.921 802 4(4) for a system with the nuclear mass of a positron. In all cases the energy varies smoothly as . It is found that for the finite nuclear mass case, in agreement with previous work for the fixed nucleus mass system, the outer electron remains localised near the nucleus at Z = Zc. Additionally, the electron probability distribution is calculated to determine the behaviour of the electrons at low Z
Identities at odds: embedded and implicit language policing in the internationalized workplace
This study offers an interaction analytic account of how linguistic identities in internationalized workplaces in Denmark are indexed against members' institutional positions in particular interactional contexts. Where language policy may not be explicitly articulated between members, it is still embedded in how participants micro-manage their interactions and implicit in how members display orientations to deviance, in the case of encountering others in the workplace whose language repertoires or preferences do not meet with expectation pertaining to the institutional position they hold. The study uses recordings of naturally occurring interaction in different international workplace settings and argues for greater attention to be paid to the actual language-policy practices in international workplace settings, as an entry point into developing a more nuanced understanding of the practices through which professional identities are brought about, affirmed or contested, and the linguistic considerations that are implicated in this
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