482 research outputs found
Can Ultrasound Be Used to Improve the Palpation Skills of Physicians in Training? A Prospective Study
BackgroundAccurate diagnosis of musculoskeletal disorders relies heavily on the physical examination, including accurate palpation of musculoskeletal structures. The literature suggests that there has been a deterioration of physical examination skills among medical students and residents, in part due to increased reliance on advanced imaging. It has been shown that knowledge of musculoskeletal anatomy and physical examination skills improve with the use of ultrasound; however, the literature is limited.ObjectiveTo determine whether ultrasound can improve the ability of physicians in training (residents) to palpate the long head of the biceps tendon (LHBT) in the bicipital groove.DesignProspective study design.SettingTertiary care center.ParticipantsTen physical medicine and rehabilitation residents served as subjects. Exclusion criteria included the presence of any condition that precluded their ability to palpate. Three volunteers were used as models. Model exclusion criteria included anything that distorted normal shoulder anatomy or inhibited examiner palpation. Three investigators with experience performing diagnostic musculoskeletal ultrasound were used to confirm palpation attempts.MethodsSubjects attempted to palpate the LHBT bilaterally in the bicipital groove of each model. Investigators assessed the accuracy of the palpation attempt using real‐time ultrasonography. Subjects participated in a 30‐minute ultrasound‐assisted training session learning how to palpate the LHBT in the bicipital groove with ultrasound confirmation. After the ultrasound training session, subjects again attempted to palpate the LHBT in the bicipital groove of each model with investigator confirmation.Main Outcome MeasurementsLHBT palpation accuracy rates preintervention versus postintervention.ResultsPretraining LHBT palpation accuracy was 20% (12/60 attempts). Post‐ultrasound training session accuracy was 51.7% (31/60 attempts; P ≤ .001).ConclusionsOur findings demonstrate that palpation accuracy improves after ultrasound assisted LHBT palpation training. These data suggest that the use of ultrasound may be beneficial when teaching musculoskeletal palpation skills to health care professionals.Level of EvidenceIIPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146948/1/pmr2730.pd
Use of gonadotropin releasing hormone (GnRH) vaccines for behavioural and reproductive control in managed Asian elephant Elephas maximus and African elephant Loxodonta africana populations
Because of their size and reproductive anatomy, surgical castration is not a practical option in adult elephants. However, similar to other species in human care, the effects of gonadectomy are desired in specific situations. This may be for contraceptive purposes, or for behavioural or veterinary management of elephants in human care or wild elephants managed in small reserves. Research into non‐surgical contraceptive measures for wild and domestic animals has resulted in an array of hormonal and immunological options to downregulate gonadal function. Driven by the production‐animal industry, commercial gonadotrophin releasing hormone (GnRH) vaccines are readily and cheaply available. This immunocontraceptive is effective in both males and females as it inhibits gonadotrophic hormone release and, thus, downstream stimulation of testicles and ovaries. Here, available studies from the past 10 years on the GnRH vaccine application in male and female elephants are reviewed. Furthermore, we add our own experience gathered from the treatment of male African elephants Loxodonta africana and female Asian elephants Elephas maximus in human care. The GnRH vaccine offers a viable approach for various management purposes. It should be noted that the GnRH vaccine was not primarily designed as a reversible contraceptive. Therefore, its use must be well justified on an individual basis and the effects closely monitored.https://zslpublications.onlinelibrary.wiley.com/journal/174810902020-07-01hj2020Anatomy and PhysiologyProduction Animal Studie
Genome analysis provides insights into microaerobic toluene-degradation pathway of Zoogloea oleivorans BucT
Zoogloea oleivorans, capable of using toluene as a sole source of carbon and energy, was earlier found to be an active degrader under microaerobic conditions in aquifer samples. To uncover the genetic background of the ability of microaerobic toluene degradation in Z. oleivorans, the whole-genome sequence of the type strain Buc(T) was revealed. Metatranscriptomic sequence reads, originated from a previous SIP study on microaerobic toluene degradation, were mapped on the genome. The genome (5.68 Mb) had a mean G + C content of 62.5%, 5005 protein coding gene sequences and 80 RNA genes. Annotation predicted that 66 genes were involved in the metabolism of aromatic compounds. Genome analysis revealed the presence of a cluster with genes coding for a multicomponent phenol-hydroxylase system and a complete catechol meta-cleavage pathway. Another cluster flanked by mobile-element protein coding genes coded a partial catechol meta-cleavage pathway including a subfamily I.2.C-type extradiol dioxygenase. Analysis of metatranscriptomic data of a microaerobic toluene-degrading enrichment, containing Z . oleivorans as an active-toluene degrader revealed that a toluene dioxygenase-like enzyme was responsible for the ring-hydroxylation, while enzymes of the partial catechol meta-cleavage pathway coding cluster were responsible for further degradation of the aromatic ring under microaerobic conditions. This further advances our understanding of aromatic hydrocarbon degradation between fully oxic and strictly anoxic conditions
Nitrogen isotopic analysis of carbonate-bound organic matter in modern and fossil fish otoliths
The nitrogen isotopic composition (δ^(15)N) of otolith-bound organic matter (OM) is a potential source of information on dietary history of bony fishes. In contrast to the δ^(15)N of white muscle tissue, the most commonly used tissue for ecological studies, the δ^(15)N of otolith-bound OM (δ^(15)N_(oto)) provides a record of whole life history. More importantly, δ^(15)N_(oto) can be measured in contexts where tissue is not available, for example, in otolith archives and sedimentary deposits. The utility and robustness of otolith δ^(15)N analysis was heretofore limited by the low N content of otoliths, which precluded the routine measurement of individual otoliths as well as the thorough cleaning of otolith material prior to analysis. Here, we introduce a new method based on oxidation to nitrate followed by bacterial conversion to N_2O. The method requires 200-fold less N compared to traditional combustion approaches, allowing for thorough pre-cleaning and replicated analysis of individual otoliths of nearly any size. Long term precision of δ^(15)N_(oto) is 0.3‰. Using an internal standard of Atlantic cod (Gadus morhua) otoliths, we examine the parameters of the oxidative cleaning step with regard to oxidant (potassium persulfate and sodium hypochlorite), temperature, and time. We also report initial results that verify the usefulness of δ^(15)N_(oto) for ecological studies. For three salmonid species, left and right otoliths from the same fish are indistinguishable. We find that the δ^(15)N_(oto) of pink salmon (Oncorhynchus gorbuscha) is related to the size of the fish for this species. We find that intra-cohort δ^(15)N_(oto) standard deviation for wild pink salmon, farmed brown trout (Salmo trutta), and farmed rainbow trout (Oncorhynchus mykiss) are all 0.4‰ or less, suggesting that δ^(15)N_(oto) will be valuable for population-level studies. Lastly, our protocol yields reproducible data for both δ^(15)N_(oto) and otolith N content in 17th century Atlantic cod otoliths. We find that 17th century cod are approximately 2 ‰ higher than modern cod, arguably consistent with either the larger size of the otoliths (and thus inferred for the fish) or with changes in baseline (primary producer) δ^(15)N in the modern coastal ocean compared to the past. All told, the results of this study bode well for the utility of otolith-bound δ15N for investigating the environment and ecology of modern and past fish
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Nitrogen isotopic analysis of carbonate-bound organic matter in modern and fossil fish otoliths
The nitrogen isotopic composition (δ^(15)N) of otolith-bound organic matter (OM) is a potential source of information on dietary history of bony fishes. In contrast to the δ^(15)N of white muscle tissue, the most commonly used tissue for ecological studies, the δ^(15)N of otolith-bound OM (δ^(15)N_(oto)) provides a record of whole life history. More importantly, δ^(15)N_(oto) can be measured in contexts where tissue is not available, for example, in otolith archives and sedimentary deposits. The utility and robustness of otolith δ^(15)N analysis was heretofore limited by the low N content of otoliths, which precluded the routine measurement of individual otoliths as well as the thorough cleaning of otolith material prior to analysis. Here, we introduce a new method based on oxidation to nitrate followed by bacterial conversion to N_2O. The method requires 200-fold less N compared to traditional combustion approaches, allowing for thorough pre-cleaning and replicated analysis of individual otoliths of nearly any size. Long term precision of δ^(15)N_(oto) is 0.3‰. Using an internal standard of Atlantic cod (Gadus morhua) otoliths, we examine the parameters of the oxidative cleaning step with regard to oxidant (potassium persulfate and sodium hypochlorite), temperature, and time. We also report initial results that verify the usefulness of δ^(15)N_(oto) for ecological studies. For three salmonid species, left and right otoliths from the same fish are indistinguishable. We find that the δ^(15)N_(oto) of pink salmon (Oncorhynchus gorbuscha) is related to the size of the fish for this species. We find that intra-cohort δ^(15)N_(oto) standard deviation for wild pink salmon, farmed brown trout (Salmo trutta), and farmed rainbow trout (Oncorhynchus mykiss) are all 0.4‰ or less, suggesting that δ^(15)N_(oto) will be valuable for population-level studies. Lastly, our protocol yields reproducible data for both δ^(15)N_(oto) and otolith N content in 17th century Atlantic cod otoliths. We find that 17th century cod are approximately 2 ‰ higher than modern cod, arguably consistent with either the larger size of the otoliths (and thus inferred for the fish) or with changes in baseline (primary producer) δ^(15)N in the modern coastal ocean compared to the past. All told, the results of this study bode well for the utility of otolith-bound δ15N for investigating the environment and ecology of modern and past fish
Quantum control of hybrid nuclear-electronic qubits
Pulsed magnetic resonance is a wide-reaching technology allowing the quantum
state of electronic and nuclear spins to be controlled on the timescale of
nanoseconds and microseconds respectively. The time required to flip either
dilute electronic or nuclear spins is orders of magnitude shorter than their
decoherence times, leading to several schemes for quantum information
processing with spin qubits. We investigate instead the novel regime where the
eigenstates approximate 50:50 superpositions of the electronic and nuclear spin
states forming "hybrid nuclear-electronic" qubits. Here we demonstrate quantum
control of these states for the first time, using bismuth-doped silicon, in
just 32 ns: this is orders of magnitude faster than previous experiments where
pure nuclear states were used. The coherence times of our states are five
orders of magnitude longer, reaching 4 ms, and are limited by the
naturally-occurring 29Si nuclear spin impurities. There is quantitative
agreement between our experiments and no-free-parameter analytical theory for
the resonance positions, as well as their relative intensities and relative
Rabi oscillation frequencies. In experiments where the slow manipulation of
some of the qubits is the rate limiting step, quantum computations would
benefit from faster operation in the hybrid regime.Comment: 20 pages, 8 figures, new data and simulation
Effects of GnRH vaccination in wild and captive African Elephant bulls (Loxodonta africana) on reproductive organs and semen quality
OBJECTIVES:
Although the African elephant (Loxodonta africana) is classified as endangered by the International
Union for Conservation of Nature (IUCN), in some isolated habitats in southern Africa,
contraception is of major interest due to local overpopulation. GnRH vaccination has been
promoted as a non-invasive contraceptive measure for population management of overabundant
wildlife. We tested the efficacy of this treatment for fertility control in elephant bulls.
METHODS:
In total, 17 male African elephants that were treated with a GnRH vaccine were examined in
two groups. In the prospective study group 1 (n = 11 bulls, ages: 8±36 years), semen quality,
the testes, seminal vesicles, ampullae and prostate, which were all measured by means of
transrectal ultrasound, and faecal androgen metabolite concentrations were monitored over
a three-year period. Each bull in the prospective study received 5 ml of Improvac® (1000 μg
GnRH conjugate) intramuscularly after the first examination, followed by a booster six
weeks later and thereafter every 5±7 months. In a retrospective study group (group 2, n = 6,
ages: 19±33 years), one examination was performed on bulls which had been treated with
GnRH vaccine for 5±11 years.
RESULTS:
In all bulls of group 1, testicular and accessory sex gland sizes decreased significantly after
the third vaccination. In six males examined prior to vaccination and again after more than
five vaccinations, the testis size was reduced by 57.5%. Mean testicular height and length
decreased from 13.3 ± 2.6 cm x 15.2 ± 2.8 cm at the beginning to 7.6 ± 2.1 cm x 10.2 ± 1.8
cm at the end of the study. Post pubertal bulls (>9 years, n = 6) examined prior to vaccination
produced ejaculates with viable spermatozoa (volume: 8±175 ml, sperm concentration:
410-4000x106/ml, total motility: 0±90%), while after 5±8 injections, only 50% of these bulls
produced ejaculates with a small number of immotile spermatozoa. The ejaculates of group
2 bulls (vaccinated >8 times) were devoid of spermatozoa. Faecal androgen metabolite concentrations
measured in captive males decreased significantly after the fourth vaccination.
None of the males entered musth during the treatment period.
CONCLUSIONS:
Our results showed a marked decrease in semen quality, testicle and secondary sex gland
sizes following repeated GnRH vaccinations. After 2±4 years of continuous treatment every
5±7 months, the effects were similar to surgical castration.ISIScopu
Anaerobic Microbial Degradation of Hydrocarbons: From Enzymatic Reactions to the Environment
Hydrocarbons are abundant in anoxic environments and pose biochemical challenges to their anaerobic degradation by microorganisms. Within the framework of the Priority Program 1319, investigations funded by the Deutsche Forschungsgemeinschaft on the anaerobic microbial degradation of hydrocarbons ranged from isolation and enrichment of hitherto unknown hydrocarbon-degrading anaerobic microorganisms, discovery of novel reactions, detailed studies of enzyme mechanisms and structures to process-oriented in situ studies. Selected highlights from this program are collected in this synopsis, with more detailed information provided by theme-focused reviews of the special topic issue on 'Anaerobic biodegradation of hydrocarbons' [this issue, pp. 1-244]. The interdisciplinary character of the program, involving microbiologists, biochemists, organic chemists and environmental scientists, is best exemplified by the studies on alkyl-/arylalkylsuccinate synthases. Here, research topics ranged from in-depth mechanistic studies of archetypical toluene-activating benzylsuccinate synthase, substrate-specific phylogenetic clustering of alkyl-/arylalkylsuccinate synthases (toluene plus xylenes, p-cymene, p-cresol, 2-methylnaphthalene, n-alkanes), stereochemical and co-metabolic insights into n-alkane-activating (methylalkyl) succinate synthases to the discovery of bacterial groups previously unknown to possess alkyl-/arylalkylsuccinate synthases by means of functional gene markers and in situ field studies enabled by state-of-the-art stable isotope probing and fractionation approaches. Other topics are Mo-cofactor-dependent dehydrogenases performing O-2-independent hydroxylation of hydrocarbons and alkyl side chains (ethylbenzene, p-cymene, cholesterol, n-hexadecane), degradation of p-alkylated benzoates and toluenes, glycyl radical-bearing 4-hydroxyphenylacetate decarboxylase, novel types of carboxylation reactions (for acetophenone, acetone, and potentially also benzene and naphthalene), W-cofactor-containing enzymes for reductive dearomatization of benzoyl-CoA (class II benzoyl-CoA reductase) in obligate anaerobes and addition of water to acetylene, fermentative formation of cyclohexanecarboxylate from benzoate, and methanogenic degradation of hydrocarbons
Search for Doubly-Charged Higgs Boson Production at HERA
A search for the single production of doubly-charged Higgs bosons H^{\pm \pm}
in ep collisions is presented. The signal is searched for via the Higgs decays
into a high mass pair of same charge leptons, one of them being an electron.
The analysis uses up to 118 pb^{-1} of ep data collected by the H1 experiment
at HERA. No evidence for doubly-charged Higgs production is observed and mass
dependent upper limits are derived on the Yukawa couplings h_{el} of the Higgs
boson to an electron-lepton pair. Assuming that the doubly-charged Higgs only
decays into an electron and a muon via a coupling of electromagnetic strength
h_{e \mu} = \sqrt{4 \pi \alpha_{em}} = 0.3, a lower limit of 141 GeV on the
H^{\pm\pm} mass is obtained at the 95% confidence level. For a doubly-charged
Higgs decaying only into an electron and a tau and a coupling h_{e\tau} = 0.3,
masses below 112 GeV are ruled out.Comment: 15 pages, 3 figures, 1 tabl
Forward pi^0 Production and Associated Transverse Energy Flow in Deep-Inelastic Scattering at HERA
Deep-inelastic positron-proton interactions at low values of Bjorken-x down
to x \approx 4.10^-5 which give rise to high transverse momentum pi^0 mesons
are studied with the H1 experiment at HERA. The inclusive cross section for
pi^0 mesons produced at small angles with respect to the proton remnant (the
forward region) is presented as a function of the transverse momentum and
energy of the pi^0 and of the four-momentum transfer Q^2 and Bjorken-x.
Measurements are also presented of the transverse energy flow in events
containing a forward pi^0 meson. Hadronic final state calculations based on QCD
models implementing different parton evolution schemes are confronted with the
data.Comment: 27 pages, 8 figures and 3 table
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