1,444 research outputs found
Evidence for engraftment of human bone marrow cells in non-lethally irradiated baboons
Background. Prior to organ harvesting, an attempt was made to modulate the donor's immune responses against prospective xenogeneic recipients by infusion of 'recipient-type' bone marrow. Methods. For this purpose, baboons conditioned with total lymphoid irradiation were given 6x108 unmodified human bone marrow cells/kg body weight with no subsequent treatment. Results. Animals survived until they were euthanized at 18 months. Using primers specific for human chorionic gonadotrophin gene, the presence of human DNA was confirmed by polymerase chain reaction in the blood of one animal for up to 18 months after cell transplantation; in the other animal, xenogeneic chimerism became undetectable in the blood at 6 months after bone marrow infusion. However, tissue samples obtained from both animals at the time they were euthanized bad evidence of donor (human) DNA. Additionally, the presence of donor DNA in individually harvested colonies of erythroid and myeloid lineages suggested that infused human bone marrow cells had engrafted across the xenogeneic barrier in both baboons. Conclusions. Bone marrow transplantation from human to baboon leads to establishment of chimerism and modulation of donor-specific immune reactivity, which suggests that this strategy could be reproducibly employed to crease 'surrogate' tolerogenesis in prospective donors for subsequent organ transplantation across xenogeneic barriers
Bifurcation analysis of the behavior of partially wetting liquids on a rotating cylinder
We discuss the behavior of partially wetting liquids on a rotating cylinder
using a model that takes into account the effects of gravity, viscosity,
rotation, surface tension and wettability. Such a system can be considered as a
prototype for many other systems where the interplay of spatial heterogeneity
and a lateral driving force in the proximity of a first- or second-order phase
transition results in intricate behavior. So does a partially wetting drop on a
rotating cylinder undergo a depinning transition as the rotation speed is
increased, whereas for ideally wetting liquids the behavior \bfuwe{only changes
quantitatively. We analyze the bifurcations that occur when the rotation speed
is increased for several values of the equilibrium contact angle of the
partially wetting liquids. This allows us to discuss how the entire bifurcation
structure and the flow behavior it encodes changes with changing wettability.
We employ various numerical continuation techniques that allow us to track
stable/unstable steady and time-periodic film and drop thickness profiles. We
support our findings by time-dependent numerical simulations and asymptotic
analyses of steady and time-periodic profiles for large rotation numbers
Bifurcation analysis of the behavior of partially wetting liquids on a rotating cylinder
We discuss the behavior of partially wetting liquids on a rotating cylinder using a model
that takes into account the effects of gravity, viscosity, rotation, surface tension and wettability. Such a system can be considered as a prototype for many other systems where the interplay of spatial heterogeneity and a lateral driving force in the proximity of a first- or second-order phase transition results in intricate behavior. So does a partially wetting drop
on a rotating cylinder undergo a depinning transition as the rotation speed is increased, whereas for ideally wetting liquids the behavior only changes quantitatively. We analyze the bifurcations that occur when the rotation speed is increased for several values of the
equilibrium contact angle of the partially wetting liquids. This allows us to discuss how the entire bifurcation structure and the flow behavior it encodes changes with changing wettability. We employ various numerical continuation techniques that allow us to track stable/unstable steady and time-periodic film and drop thickness profiles. We support our findings by time-dependent numerical simulations and asymptotic analyses of steady and time-periodic profiles for large rotation numbers
Sr-Nd isotope geochemistry of the early Precambrian sub-alkaline mafic igneous rocks from the southern Bastar craton, Central India
Sr–Nd isotope data are reported for the early Precambrian sub-alkaline mafic igneous rocks of the southern Bastar craton, central India. These mafic rocks are mostly dykes but there are a few volcanic exposures. Field relationships together with the petrological and geochemical characteristics of these mafic dykes divide them into two groups; Meso-Neoarchaean sub-alkaline mafic dykes (BD1) and Paleoproterozoic (1.88 Ga) sub-alkaline mafic dykes (BD2). The mafic volcanics are Neoarchaean in age and have very close geochemical relationships with the BD1 type. The two groups have distinctly different concentrations of high-field strength (HFSE) and rare earth elements (REE). The BD2 dykes have higher concentrations of HFSE and REE than the BD1 dykes and associated volcanics and both groups have very distinctive petrogenetic histories. These rocks display a limited range of initial 143Nd/144Nd but a wide range of apparent initial 87Sr/86Sr. Initial 143Nd/144Nd values in the BD1 dykes and associated volcanics vary between 0.509149 and 0.509466 and in the BD2 dykes the variation is between 0.510303 and 0.510511. All samples have positive εNd values the BD1 dykes and associated volcanics have εNd values between +0.3 and +6.5 and the BD2 dykes between +1.9 to +6.0. Trace element and Nd isotope data do not suggest severe crustal contamination during the emplacement of the studied rocks. The positive εNd values suggest their derivation from a depleted mantle source. Overlapping positive εNd values suggest that a similar mantle source tapped by variable melt fractions at different times was responsible for the genesis of BD1 (and associated volcanics) and BD2 mafic dykes. The Rb–Sr system is susceptible to alteration and resetting during post-magmatic alteration and metamorphism. Many of the samples studied have anomalous apparent initial 87Sr/86Sr suggesting post-magmatic changes of the Rb–Sr system which severely restricts the use of Rb–Sr for petrogenetic interpretation
Estimation of efficiency of the use of financial resources on enterprises
Стаття присвячена дослідженню теоретичних та практичних питань аналітичного забезпечення управління використанням фінансових ресурсів підприємств. Запропоновані комплексні показники оцінки даного процесуThe article is devoted to research of theoretical and practical questions of the analytical providing of management the use of financial resources of enterprises. The complex indexes of estimation of this process are offere
A discrete genetic locus confers xyloglucan metabolism in select human gut Bacteroidetes
A well-balanced human diet includes a significant intake of non-starch polysaccharides, collectively termed 'dietary fibre', from the cell walls of diverse fruits and vegetables. Owing to the paucity of alimentary enzymes encoded by the human genome, our ability to derive energy from dietary fibre depends on the saccharification and fermentation of complex carbohydrates by the massive microbial community residing in our distal gut. The xyloglucans (XyGs) are a ubiquitous family of highly branched plant cell wall polysaccharides whose mechanism(s) of degradation in the human gut and consequent importance in nutrition have been unclear. Here we demonstrate that a single, complex gene locus in Bacteroides ovatus confers XyG catabolism in this common colonic symbiont. Through targeted gene disruption, biochemical analysis of all predicted glycoside hydrolases and carbohydrate-binding proteins, and three-dimensional structural determination of the vanguard endo-xyloglucanase, we reveal the molecular mechanisms through which XyGs are hydrolysed to component monosaccharides for further metabolism. We also observe that orthologous XyG utilization loci (XyGULs) serve as genetic markers of XyG catabolism in Bacteroidetes, that XyGULs are restricted to a limited number of phylogenetically diverse strains, and that XyGULs are ubiquitous in surveyed human metagenomes. Our findings reveal that the metabolism of even highly abundant components of dietary fibre may be mediated by niche species, which has immediate fundamental and practical implications for gut symbiont population ecology in the context of human diet, nutrition and health
Safety of carboxymethylcellulose/polyethylene oxide for the prevention of adhesions in lumbar disc herniation – consecutive case series review
Protocol: Health, social care and technological interventions to improve functional ability of older adults: Evidence and gap map
This is the final version. Available on open access from Wiley via the DOI in this frecordThis is a protocol for a Campbell Evidence and Gap Map. The objectives are to identify and assess the available evidence on health, social care and technological interventions to improve functional ability among older adults
Potential unique causes of burnout for chiropractic professionals
Objective The objective of this narrative review is to discuss the potential for burnout in chiropractic practitioners. This discussion is grounded in the job demands-resource model, the conservation of resources model, the unique profession-specific stressors experienced by chiropractors, and information from similar health care professions. Methods A search using both the indexed (PubMed and PsychLit) and nonindexed psychosocial literature was used. Other resources included the Cochrane Library, articles from governing bodies of the chiropractic profession, trade magazines, and research conferences and symposium proceedings. Articles were analyzed following the grounded theory principles: open coding and memos for conceptual labeling, axial coding and memos for category building, and selective coding for model building. Results Potential stressors unique to doctors of chiropractic include factors associated with physical workload, role stress, and mental and emotional demands. Conclusions There are unique chiropractic-specific occupational characteristics that possibly contribute to burnout in the chiropractic professionals. These findings emphasize the need for assessing and measuring burnout and attrition within the chiropractic profession
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