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Capillary supply of the tibialis anterior muscle in young, healthy, and moderately active men and women

Tibialis anterior muscle biopsies from moderately active men and women (21-30 yr; n = 30) were examined to determine potential gender differences in capillarization. The fiber type proportions [type I (T1) similar to73%] were unaffected by gender. The men (M) had significantly (P < 0.001) larger fibers than the women (W), with a greater gender effect for type II (T2) fibers P < 0.001). The M and W

Photoemission spectromicroscopy study of a Bi2Sr2CaCu2O8+delta single crystal

Using photoemission spectromicroscopy at sub-micron lateral resolution we studied two superconductor systems of high fundamental and practical importance, such as Bi2Sr2CaCu2O8+delta and MgB2. Our findings demonstrate the importance of considering, for this class of systems, the possible presence of spatial inhomogeneities in interpreting the results of conventional photoemission experiments, whic

Biodegradation and biocompatability of a calcium sulphate-hydroxyapatite bone substitute.

An injectable material consisting of calcium sulphate mixed with hydroxyapatite was investigated as a possible alternative to autograft in the restoration of bone defects. The material was studied both in vitro in simulated body fluid (SBF) and in vivo when implanted in rat muscles and into the proximal tibiae of rabbits. Variation in the strength and weight of the material during ageing in SBF wa

Effects of tadpole grazing on periphytic algae in ponds

Tadpole impact on periphytic algae was estimated with an exclosure experiment in the field. Algae growth on control (exposed) and experimental (netted-in) perspex plates was measured in 12 ponds in 1991 and 8 in 1993. An index of snail (Lymnea and Planorbis) presence in the ponds was used to correct their effect. Grazing pressure (difference in amount of algae between control and experimental plat

RhoH is important for positive thymocyte selection and T-cell receptor signaling

RhoH is a small GTPase expressed only in the hematopoietic system. With the use of mice with targeted disruption of the RhoH gene, we demonstrated that RhoH is crucial for thymocyte maturation during DN3 to DN4 transition and during positive selection. Furthermore, the differentiation and expansion of DN3 and DN4 thymocytes in vitro were severely impaired. These defects corresponded to defective T

Why are small seeds dispersed through animal guts: large numbers or seed size per se?

Long-distance dispersal of seeds is an important process in metapopulation dynamics and in plant migrations, but at the same time extremely difficult to observe or quantify directly. If seed dispersal ability were related to attributes of seeds or motherplants, long-distance seed dispersal would be predictable by indirect approximation using easy-to-measure traits. Seed size has been suggested to

Subarctic atmospheric aerosol composition: 1. Ambient aerosol characterization

Subarctic aerosol was sampled during July 2007 at the Abisko Research Station Stordalen field site operated by the Royal Swedish Academy of Sciences. Located in northern Sweden at 68 degrees latitude and 385 m above sea level (m asl), this site is classified as a semicontinuous permafrost mire. Number density, size distribution, cloud condensation nucleus properties, and chemical composition of th

Synthesis and biological evaluation of reversible inhibitors of IdeS, a bacterial cysteine protease and virulence determinant

Analogues of the irreversible protease inhibitors TPCK and TLCK have been synthesized and tested as inhibitors of the bacterial cysteine protease IdeS excreted by Streptococcus pyogenes. Eight compounds were identified as inhibitors of IdeS in an in vitro assay. The most potent compounds contained an aldehyde function, thus acting as efficient reversible inhibitors, nitrile and azide derivatives s

Specific conditions for enhancement of lipoprotein lipase activity by platelets

Homogenates of human blood platelets, but not of red blood cells, have been found to stimulate lipoprotein lipase activity only when assayed against an emulsified triglyceride substrate sonicated for a short period of time. The degree of stimulation was inversely related to the time of sonication of the substrate. Using chylomicrons as substrate no stimulation of lipoprotein lipase activity by pla

A new N-acetyl-beta-D-hexosaminidase disease with late onset of progressive neurological symptoms

Clinical data are presented on a 30-year-old male with normal early development (4-5 years) but subsequent progressive impairment of psychomotor functions. He has marked kyphoscoliosis and talipes calcaneo-valgus. The organs appear normal and the patient can walk unaided and feed himself although he does not recognize his parents. He has normal fundi oculi. Biochemical data show an absence of muco

Acute myeloid leukemia with inv(16)(p13q22): Involvement of cervical lymph nodes and tonsils is common and may be a negative prognostic sign.

Acute myeloid leukemia (AML) with inv(16)(p13q22) or the variant t(16;16)(p13;q22), is strongly associated with the FAB subtype M4Eo. A high incidence of CNS involvement was reported in the 1980s, but otherwise little is known about the pattern of extamedullary leukemia (EML) manifestations in this AML type. We have compiled clinical and cytogenetic data on 27 consecutive AML cases with inv(16)/t(

Analysis of wave propagation in stratified structures using circuit analogs, with application to electromagnetic absorbers

This paper presents an overview of how circuit models can be used for analysing wave propagation in stratified structures. Relatively complex structures can be analysed using models which are accessible to undergraduate students. Homogeneous slabs are modelled as transmission lines, and thin sheets between the slabs are modelled as lumped elements. It is seen that electric material properties act

Preferential Interface Nucleation: An Expansion of the VLS Growth Mechanism for Nanowires

A review and expansion of the fundamental processes of the vapor-liquid-solid (VLS) growth mechanism for nanowires is presented. Although the focus is on nanowires, most of the concepts may be applicable to whiskers, nanotubes, and other unidirectional growth. Important concepts in the VLS mechanism such as preferred deposition, supersaturation, and nucleation are examined. Nanowire growth is feas

Finding the right partner: Rural homogamy in nineteenth-century Sweden

In pre-industrial society, choosing a marriage partner was a crucial process, and especially so for landowners. This study focuses on social aspects of mate selection in five rural parishes in southern Sweden between 1829 and 1894, using an individual-level database containing information on a large number of marriages and the social origins of the marrying couple regardless of whether they were b

Refractometry of microscopic objects with digital holography

Digital holography has some desirable properties for refractometry of microscopic objects since it gives phase and amplitude information of an object in all depths of focus from one set of exposures. We show that the amplitude part of the image can be used to observe how the Becke lines move between different depths of focus and hence determine whether an object has a higher or a lower index of re

Multistage growth and reworking of the Palaeoproterozoic crust in the Bergslagen area, southern Sweden: evidence from U-Pb geochronology

The Svecofennian Domain of the Fennoscandian Shield constitutes a considerable volume of Palaeoproterozoic crustal growth, 2.1-1.86 Ga ago, in between the Archaean craton in the NE and the 1.85-1.65 Ga Transscandinavian Igneous Belt (TIB) in the south and west. The Bergslagen area is a classical ore province located in the southwestern part of the Svecofennian Domain of southcentral Sweden. Its no