667 research outputs found
Implications for room lighting and the duration of acclimation protocols on the dosimetry of inhaled drugs in rats
Inhaled administration of test materials to animals has technical challenges for quantitative
dosimetry. Inhaled “doses” reported in non-clinical studies are often calculated using an equation
such as that of Alexander et al. [1] to estimate the respired minute volume (eRMV) from body
weight data. This approach may overlook physiological effects on lung function associated with a
formulation’s properties or habituation of animals to the “dosing” technique. Rats are insensitive
to red light [2] and anecdotal data (unpublished) suggested red lighting may induce a calmer state
in restrained rats. We hypothesized that the lighting color (red or white) and duration of restraint
tube acclimation protocols may influence the breath frequency and minute volume of rats during
inhalation exposure, representing a potential source of variability in achieved doses. Head-out
plethysmography [3] was used to investigate this hypothesis concurrent with inhaled administration
of an anti-inflammatory drug
Implications for room lighting and the duration of acclimation protocols on the dosimetry of inhaled drugs in rats
Inhaled administration of test materials to animals has technical challenges for quantitative
dosimetry. Inhaled “doses” reported in non-clinical studies are often calculated using an equation
such as that of Alexander et al. [1] to estimate the respired minute volume (eRMV) from body
weight data. This approach may overlook physiological effects on lung function associated with a
formulation’s properties or habituation of animals to the “dosing” technique. Rats are insensitive
to red light [2] and anecdotal data (unpublished) suggested red lighting may induce a calmer state
in restrained rats. We hypothesized that the lighting color (red or white) and duration of restraint
tube acclimation protocols may influence the breath frequency and minute volume of rats during
inhalation exposure, representing a potential source of variability in achieved doses. Head-out
plethysmography [3] was used to investigate this hypothesis concurrent with inhaled administration
of an anti-inflammatory drug
Are we sinking African cheetahs in India?
SIGNIFICANCE :
The current initiative to export African cheetahs to India has a limited scientific basis, placing the Asian
subspecies and the translocated animals at risk. There is no evidence that this will benefit African cheetah
conservation. We call for a globally coordinated approach to cheetah conservation, based on sound science.http://www.sajs.co.zahj2023Mammal Research InstituteZoology and Entomolog
Why humans kill animals and why we cannot avoid it
Killing animals has been a ubiquitous human behaviour throughout history, yet it is becoming increasingly controversial and criticised in some parts of contemporary human society. Here we review 10 primary reasons why humans kill animals, discuss the necessity (or not) of these forms of killing, and describe the global ecological context for human killing of animals. Humans historically and currently kill animals either directly or indirectly for the following reasons: (1) wild harvest or food acquisition, (2) human health and safety, (3) agriculture and aquaculture, (4) urbanisation and industrialisation, (5) invasive, overabundant or nuisance wildlife control, (6) threatened species conservation, (7) recreation, sport or entertainment, (8) mercy or compassion, (9) cultural and religious practice, and (10) research,education and testing. While the necessity of some forms of animal killing is debatable and further depends on individual values, we emphasise that several of these forms of animal killing are a necessary component of our inescapable involvement in a single, functioning, finite, global food web. We conclude that humans (and all other animals) cannot live in a way that does not require animal killing either directly or indirectly, but humans can modify some of these killing behaviours in ways that improve the welfare of animals while they are alive, or to reduce animal suffering whenever they must be killed. We encourage a constructive dialogue that (1) accepts and permits human participation in one enormous global food web dependent on animal killing and (2) focuses on animal welfare and environmental sustainability. Doing so will improve the lives of both wild and domestic animals to a greater extent than efforts to avoid, prohibit or vilify human animal-killing behaviour. Animal ethics Conservation biology Culling Factory farmingpublishedVersio
Why humans kill animals and why we cannot avoid it
Killing animals has been a ubiquitous human behaviour throughout history, yet it is becoming increasingly controversial and criticised in some parts of contemporary human society. Here we review 10 primary reasons why humans kill animals, discuss the necessity (or not) of these forms of killing, and describe the global ecological context for human killing of animals. Humans historically and currently kill animals either directly or indirectly for the following reasons: (1) wild harvest or food acquisition, (2) human health and safety, (3) agriculture and aquaculture, (4) urbanisation and industrialisation, (5) invasive, overabundant or nuisance wildlife control, (6) threatened species conservation, (7) recreation, sport or entertainment, (8) mercy or compassion, (9) cultural and religious practice, and (10) research,education and testing. While the necessity of some forms of animal killing is debatable and further depends on individual values, we emphasise that several of these forms of animal killing are a necessary component of our inescapable involvement in a single, functioning, finite, global food web. We conclude that humans (and all other animals) cannot live in a way that does not require animal killing either directly or indirectly, but humans can modify some of these killing behaviours in ways that improve the welfare of animals while they are alive, or to reduce animal suffering whenever they must be killed. We encourage a constructive dialogue that (1) accepts and permits human participation in one enormous global food web dependent on animal killing and (2) focuses on animal welfare and environmental sustainability. Doing so will improve the lives of both wild and domestic animals to a greater extent than efforts to avoid, prohibit or vilify human animal-killing behaviour. Animal ethics Conservation biology Culling Factory farmingpublishedVersio
The incidence and prevalence of systemic lupus erythematosus in the UK, 1999–2012
Objectives: To estimate the incidence and prevalence of systemic lupus erythematosus (SLE) in the UK over the period 1999–2012.
Methods: A retrospective cohort study using the Clinical Practice Research Datalink (CPRD). The incidence was calculated per 100 000 person-years and the prevalence was calculated per 100 000 people for the period 1999–2012 and stratified by year, age group, gender, region and ethnicity. Three definitions of SLE were explored: (1) systemic lupus, (2) a fully comprehensive definition of lupus including cutaneous only lupus and (3) requiring supporting evidence of SLE in the medical record.
Results: Using our primary definition of SLE, the incidence during the study period was 4.91/100 000 person-years (95% CI 4.73 to 5.09), with an annual 1.8% decline (p<0.001). In contrast, the prevalence increased from 64.99/100 000 in 1999 (95% CI 62.04 to 67.93) (0.065%) to 97.04/100 000 in 2012 (95% CI 94.18 to 99.90) (0.097%). SLE was six times more common in women. The peak age of incidence was 50–59 years. There was regional variation in both incidence and prevalence. People of Black Caribbean ethnicity had the highest incidence and prevalence. Alternative definitions of SLE increased (definition 2) or decreased (definition 3) estimates of incidence and prevalence, but similar trends were found.
Conclusions: The incidence of SLE has been declining but the prevalence has been increasing in the UK in recent years. Age, gender, region and ethnicity are risk factors for SLE. This is the first study to report ethnic differences on the incidence and prevalence of SLE using the CPRD
‘Living a life less ordinary’: exploring the experiences of Australian men who have acquired HIV overseas
Background: Increasing international mobility has led to a growth of cross-border HIV transmission around the world. In Australia, increasing rates of HIV infections acquired overseas have been reported, particularly among men. This qualitative study explored experiences and risk perceptions of 14 Australian men who acquired HIV while living or travelling overseas from the year 2000. Methods: Symbolic interaction provided the study’s theoretical perspective and analytical framework. Australian men living with HIV who were aged 18 years and older, believed they had acquired their infection while working or travelling overseas during or after the year 2000, and were diagnosed from 2003 onwards were eligible to participate. A semistructured interview schedule was developed and tested for content validity with the study reference group. Analysis was conducted using an adapted form of grounded theory to form the basis for the development of the experiences domains. Results: Analysis produced four domains of experience: (1) a fantasy realised, (2) escaping and finding a new self or life, (3) living a life less ordinary and (4) living local but still an outsider. The description of the four experience domains highlights how risk generally, particularly sexual risk, did or did not feature in these men’s understanding of their experiences. Conclusion: Perceptions and experiences of long-term travel played a decisive role for men who acquired HIV when travelling overseas. Appealing to desired experiences such as connection to local culture or sustaining a new or adventurous life may provide important implications for guiding health promotion programs and policy
Burden of comorbidity in systemic lupus erythematosus in the UK, 1999–2012
Objective: To estimate the comorbidity associated with systemic lupus erythematosus (SLE) in the UK during 1999–2012.
Methods: A retrospective cohort study using the UK Clinical Practice Research Datalink was conducted. Prevalent cases of SLE were matched by age, sex, and practice to 4 controls. The incidence of cardiovascular disease (CVD), stroke, end-stage renal failure (ESRF), cancer, osteoporosis, and infection were calculated per 1,000 person-years during the study period and compared to controls using Poisson regression to obtain incidence rate ratios (IRRs). IRRs were adjusted for baseline age, sex, body mass index, smoking status, alcohol intake, hypertension, hyperlipidemia, Charlson Index scores, and prednisolone use. Age- and sex-specific incidence rates were calculated.
Results: When comparing the 7,732 prevalent cases of SLE with 28,079 matched controls, the unadjusted IRR was 1.98 (95% confidence interval [95% CI] 1.69–2.31) for CVD, 1.81 (95% CI 1.49–2.19) for stroke, 7.81 (95% CI 4.68–13.05) for ESRF, 1.28 (95% CI 1.17–1.40) for cancer, 2.53 (95% CI 2.27–2.82) for osteoporosis, and 1.49 (95% CI 1.40–1.58) for infection. After adjustment, the rates remained significantly higher in cases. Men with SLE had higher rates of CVD, stroke, and cancer, whereas women had higher rates of infection and osteoporosis. Those at younger ages were at the greatest relative risk compared with controls. Cases had significantly higher Charlson Index scores at baseline.
Conclusion: People with SLE in the UK have a greater burden of comorbidity and are more likely to develop CVD, stroke, ESRF, cancer, osteoporosis, and infection than people of the same age and sex
The Nova Shell and Evolution of the Recurrent Nova T Pyxidis
T Pyxidis is the prototypical recurrent nova (RN) with a mysterious nova
shell. We report new observations of the shell with HST. The knots in the shell
are expanding with velocities 500-715 km/s, for a distance of 3500 pc. The
fractional expansion of the knots is constant, and this implies no significant
deceleration. Hence, the knots were ejected by an eruption close to the year
1866. Knots have turned on after 1995, and this demonstrates that the knots are
powered by shocks from the collision of the 1866 ejecta with fast ejecta from
later RN eruptions. The 1866 ejecta has a total mass of 10^-4.5 Msun, which
with the low ejection velocity shows that the 1866 event was an ordinary nova
eruption, not a RN eruption. The accretion rate before the ordinary nova event
must have been low (around the 4x10^-11 Msun/yr expected for gravitational
radiation alone) and the matter accumulated on the surface of the white dwarf
for ~750,000 years. The current accretion rate (>10^-8 Msun/yr) is 1000X higher
than expected for a system below the period gap, with the plausible reason
being that the 1866 event started a continuing supersoft source that drives the
accretion. A key fact about T Pyx is that its accretion rate has been secularly
declining since before the 1890 eruption, with the current rate being only 3%
of its earlier rate. The decline in the observed accretion rate shows that the
supersoft source is not self-sustaining, and we calculate that the accretion in
T Pyx will effectively stop in upcoming decades. With this, T Pyx will enter a
state of hibernation, lasting for an estimated 2,600,000 years, before
gravitational radiation brings the system into contact again. Thus, T Pyx has
an evolutionary cycle going from an ordinary CV state, to its current RN state,
to a future hibernation state, and then repeating this cycle.Comment: Astrophysical Journal in press, 62 pages, 11 figures (accepted
version; minor changes and shortening
Translocations as Experiments in the Ecological Resilience of an Asocial Mega-Herbivore
Species translocations are remarkable experiments in evolutionary ecology, and increasingly critical to biodiversity conservation. Elaborate socio-ecological hypotheses for translocation success, based on theoretical fitness relationships, are untested and lead to complex uncertainty rather than parsimonious solutions. We used an extraordinary 89 reintroduction and 102 restocking events releasing 682 black rhinoceros (Diceros bicornis) to 81 reserves in southern Africa (1981–2005) to test the influence of interacting socio-ecological and individual characters on post-release survival. We predicted that the socio-ecological context should feature more prominently after restocking than reintroduction because released rhinoceros interact with resident conspecifics. Instead, an interaction between release cohort size and habitat quality explained reintroduction success but only individuals' ages explained restocking outcomes. Achieving translocation success for many species may not be as complicated as theory suggests. Black rhino, and similarly asocial generalist herbivores without substantial predators, are likely to be resilient to ecological challenges and robust candidates for crisis management in a changing world
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