4,560 research outputs found
Frustrations of fur-farmed mink
Captive animals may suffer if strongly motivated to perform activities that their housing does not allow. We investigated this experimentally for caged mink, and found that they would pay high costs to perform a range of natural behaviours, and release cortisol if their most preferred activity, swimming, was prevented.
Investigates the effect of limitations on caged mink. Popularity of fur farming; Research into the possible deprivation of mink, which result in their frustration; Details of the experiment; Impact of an access to water; Results which indicate that fur-farmed mink are still motivated to perform the same activities as their wild counterpart
Development and validation of a clinical prediction model for patient-reported pain and function after primary total knee replacement surgery
To develop and validate a clinical prediction model of patient-reported pain and function after undergoing total knee replacement (TKR). We used data of 1,649 patients from the Knee Arthroplasty Trial who received primary TKR across 34 centres in the UK. The external validation included 595 patients from Southampton University Hospital, and Nuffield Orthopaedic Centre (Oxford). The outcome was the Oxford Knee Score (OKS) 12-month after TKR. Pre-operative predictors including patient characteristics and clinical factors were considered. Bootstrap backward linear regression analysis was used. Low pre-operative OKS, living in poor areas, high body mass index, and patient-reported anxiety or depression were associated with worse outcome. The clinical factors associated with worse outcome were worse pre-operative physical status, presence of other conditions affecting mobility and previous knee arthroscopy. Presence of fixed flexion deformity and an absent or damaged pre-operative anterior cruciate ligament (compared with intact) were associated with better outcome. Discrimination and calibration statistics were satisfactory. External validation predicted 21.1% of the variance of outcome. This is the first clinical prediction model for predicting self-reported pain and function 12 months after TKR to be externally validated. It will help to inform to patients regarding expectations of the outcome after knee replacement surgery
Isolation and purification of Cu-free methanobactin from Methylosinus trichosporium OB3b
<p>Abstract</p> <p>Background</p> <p>The isolation of highly pure copper-free methanobactin is a prerequisite for the investigation of the biogeochemical functions of this chalkophore molecule produced by methane oxidizing bacteria. Here, we report a purification method for methanobactin from <it>Methylosinus trichosporium </it>OB3b cultures based on reversed-phase HPLC fractionation used in combination with a previously reported resin extraction. HPLC eluent fractions of the resin extracted product were collected and characterized with UV-vis, FT-IR, and C-1s NEXAFS spectroscopy, as well as with elemental analysis and ESI-MS.</p> <p>Results</p> <p>The results showed that numerous compounds other than methanobactin were present in the isolate obtained with resin extraction. Molar C/N ratios, mass spectrometry measurements, and UV-vis spectra indicated that methanobactin was only present in one of the HPLC fractions. On a mass basis, methanobactin carbon contributed only 32% to the total organic carbon isolated with resin extraction. Our spectroscopic results implied that besides methanobactin, the organic compounds in the resin extract comprised breakdown products of methanobactin as well as polysaccharide-like substances.</p> <p>Conclusion</p> <p>Our results demonstrate that a purification step is indispensable in addition to resin extraction in order to obtain pure methanobactin. The proposed HPLC purification procedure is suitable for semi-preparative work and provides copper-free methanobactin.</p
Safety of anti-immunoglobulin E therapy with omalizumab in allergic patients at risk of geohelminth infection
BACKGROUND: Although the role of immunoglobulin E (IgE) in immunity against helminth parasites is unclear, there is concern that therapeutic antibodies that neutralize IgE (anti-IgE) may be unsafe in subjects at risk of helminth infection. OBJECTIVE: We conducted an exploratory study to investigate the safety of omalizumab (anti-IgE) in subjects with allergic asthma and/or perennial allergic rhinitis at high risk of intestinal helminth infection. The primary safety outcome was risk of infections with intestinal helminths during anti-IgE therapy. METHODS: A randomized, double-blind, placebo-controlled trial was conducted in 137 subjects (12–30 years) at high risk of geohelminth infection. All subjects received pre-study anthelmintic treatment, followed by 52 weeks' treatment with omalizumab or placebo. RESULTS: Of the omalizumab subjects 50% (34/68) experienced at least one intestinal geohelminth infection compared with 41% (28/69) of placebo subjects [odds ratio (OR) 1.47, 95% confidence interval (CI) 0.74–2.95, one-sided P = 0.14; OR (adjusted for study visit, baseline infection status, gender and age) 2.2 (0.94–5.15); one-sided P = 0.035], providing some evidence for a potential increased incidence of geohelminth infection in subjects receiving omalizumab. Omalizumab therapy was well tolerated, and did not appear to be associated with increased morbidity attributable to intestinal helminths as assessed by clinical and laboratory adverse events, maximal helminth infection intensities and additional anthelmintic requirements. Time to first infection (OR 1.30, 95% CI 0.79–2.15, one-sided P = 0.15) was similar between treatment groups. Infection severity and response to anthelmintics appeared to be unaffected by omalizumab therapy. CONCLUSIONS: In this exploratory study of allergic subjects at high risk of helminth infections, omalizumab therapy appeared to be safe and well tolerated, but may be associated with a modest increase in the incidence of geohelminth infection
Dipolar collisions of polar molecules in the quantum regime
Ultracold polar molecules offer the possibility of exploring quantum gases
with interparticle interactions that are strong, long-range, and spatially
anisotropic. This is in stark contrast to the dilute gases of ultracold atoms,
which have isotropic and extremely short-range, or "contact", interactions. The
large electric dipole moment of polar molecules can be tuned with an external
electric field; this provides unique opportunities such as control of ultracold
chemical reactions, quantum information processing, and the realization of
novel quantum many-body systems. In spite of intense experimental efforts aimed
at observing the influence of dipoles on ultracold molecules, only recently
have sufficiently high densities been achieved. Here, we report the observation
of dipolar collisions in an ultracold molecular gas prepared close to quantum
degeneracy. For modest values of an applied electric field, we observe a
dramatic increase in the loss rate of fermionic KRb molecules due to ultrcold
chemical reactions. We find that the loss rate has a steep power-law dependence
on the induced electric dipole moment, and we show that this dependence can be
understood with a relatively simple model based on quantum threshold laws for
scattering of fermionic polar molecules. We directly observe the spatial
anisotropy of the dipolar interaction as manifested in measurements of the
thermodynamics of the dipolar gas. These results demonstrate how the long-range
dipolar interaction can be used for electric-field control of chemical reaction
rates in an ultracold polar molecule gas. The large loss rates in an applied
electric field suggest that creating a long-lived ensemble of ultracold polar
molecules may require confinement in a two-dimensional trap geometry to
suppress the influence of the attractive dipolar interactions
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