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71.
Kimberly A. Plomp Charlotte A. Roberts Una Strand Viðarsdóttir 《American journal of physical anthropology》2012,149(4):572-582
Schmorl's nodes are the result of herniations of the nucleus pulposus into the adjacent vertebral body and are commonly identified in both clinical and archaeological contexts. The current study aims to identify aspects of vertebral shape that correlate with Schmorl's nodes. Two‐dimensional statistical shape analysis was performed on digital images of the lower thoracic spine (T10–T12) of adult skeletons from the late medieval skeletal assemblages from Fishergate House, York, St. Mary Graces and East Smithfield Black Death cemeteries, London, and postmedieval Chelsea Old Church, London. Schmorl's nodes were scored on the basis of their location, depth, and size. Results indicate that there is a correlation between the shape of the posterior margin of the vertebral body and pedicles and the presence of Schmorl's nodes in the lower thoracic spine. The size of the vertebral body in males was also found to correlate with the lesions. Vertebral shape differences associated with the macroscopic characteristics of Schmorl's nodes, indicating severity of the lesion, were also analyzed. The shape of the pedicles and the posterior margin of the vertebral body, along with a larger vertebral body size in males, have a strong association with both the presence and severity of Schmorl's nodes. This suggests that shape and/or size of these vertebral components are predisposing to, or resulting in, vertically directed disc herniation. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
72.
ABSTRACT: BACKGROUND: The contribution of community medicine distributors (CMD) to prompt health service delivery in areas described as "hard-to-reach" is important but the value of their work time remains unknown and thus makes it difficult to design appropriate regular financial incentives to motivate them. This makes CMDs feel their efforts are not recognized. An attempt to estimate the value of 54 CMDs work time involved in community case management of malaria (CCMm) in a rural district in Ghana is presented. METHODS: Time spent by CMDs on CCMm activities were recorded for a period of 12 months to determine the work-time value. Cost analysis was performed in Microsoft Excel with data from CMD records and at 2007 market price in Ghana. RESULTS: A CMD spent 4.8 hours, [95% CI: 3.9; 5.3] on all CCMm-related activities per day. The time value of CMD work ranged from GHc 2.04 (US$ 2.24) to GHc 4.1 [US$ 4.6] per week and GHc 19.2 - 86.4 (US$ 21.10-94.95) per month. The gross wage outside CCMm as reported by CMD was GHc 58.4 [US$ 64.69] and value of foregone income of GHc 86.40 (US$94.95) per month, about 14-times higher than the monthly incentives of GHc 6.0 given by the CCMm programme. CONCLUSION: The value of work time and the foregone income of CMDs in CCMm are high and yet there are no regular and sustainable incentives provided for them. The results are significant to policy in designing incentives to motivate CMDs in large-scale implementation of CCMm. 相似文献
73.
James Kennedy Anna Heiða Ólafsdóttir Svandís Eva Aradóttir Svanhildur Egilsdóttir Christophe Pampoulie 《Journal of fish biology》2024,104(3):598-610
Black ruff (Centrolophus niger) is a rare and poorly studied species found in both the Atlantic and Pacific Oceans and also in the Mediterranean Sea. It is sporadically caught south of Iceland during the annual International Ecosystem Summer Survey of the Nordic Seas. In total, 43 specimens were caught from 2009 to 2021, of which 41 specimens were caught during 2017–2021. All specimens, except one, were caught using a pelagic trawl (cod-end mesh-size: 50 mm) close to the surface (trawl depth: 0–35 m) with in situ temperature ranging from 9 to 13°C. The area south of Iceland is characterized by having warmer temperatures than other areas around the island, which might be indicative of a northern limit for the distribution of black ruff. The fish were primarily in the range of 29–46 cm with a few larger individuals up to 71 cm. Fourteen fish, caught in 2017 and 2021, were dissected to gather biological information on this species. These fish were all juveniles with no obvious sign of gonad development. Correlations between total length, fork length, and standard length are presented. Otoliths were thin and delicate with a length of ~13–16 mm, and otolith size (length, width, and area) was correlated with fish size. Much of the stomach content was at an advanced stage of digestion, but some contents could be identified and consisted of invertebrates, primarily of the orders Amphipoda and Calanoida with some unidentified fish also present. 相似文献
74.
Guðbjörg Ólafsdóttir Vilhjálmur Svansson Sigurður Ingvarsson Eliane Marti Sigurbjörg Torsteinsdóttir 《Acta veterinaria Scandinavica》2008,50(1):44
One of the prerequisite for developing DNA vaccines for horses are vectors that are efficiently expressed in horse cells. 相似文献
75.
Kevin Ostacolo Adrián López García de Lomana Clémence Larat Valgerdur Hjaltalin Kristrun Yr Holm Sigríður S. Hlynsdóttir Margaret Soucheray Linda Sooman Ottar Rolfsson Nevan J. Krogan Eirikur Steingrimsson Danielle L. Swaney Margret H. Ogmundsdottir 《Traffic (Copenhagen, Denmark)》2024,25(4):e12933
Macroautophagy/autophagy is an essential catabolic process that targets a wide variety of cellular components including proteins, organelles, and pathogens. ATG7, a protein involved in the autophagy process, plays a crucial role in maintaining cellular homeostasis and can contribute to the development of diseases such as cancer. ATG7 initiates autophagy by facilitating the lipidation of the ATG8 proteins in the growing autophagosome membrane. The noncanonical isoform ATG7(2) is unable to perform ATG8 lipidation; however, its cellular regulation and function are unknown. Here, we uncovered a distinct regulation and function of ATG7(2) in contrast with ATG7(1), the canonical isoform. First, affinity-purification mass spectrometry analysis revealed that ATG7(2) establishes direct protein–protein interactions (PPIs) with metabolic proteins, whereas ATG7(1) primarily interacts with autophagy machinery proteins. Furthermore, we identified that ATG7(2) mediates a decrease in metabolic activity, highlighting a novel splice-dependent function of this important autophagy protein. Then, we found a divergent expression pattern of ATG7(1) and ATG7(2) across human tissues. Conclusively, our work uncovers the divergent patterns of expression, protein interactions, and function of ATG7(2) in contrast to ATG7(1). These findings suggest a molecular switch between main catabolic processes through isoform-dependent expression of a key autophagy gene. 相似文献
76.
77.
Kathiravan Meeran Niel Verbrigghe Johannes Ingrisch Lucia Fuchslueger Lena Müller Páll Sigurðsson Bjarni D. Sigurdsson Herbert Wachter Margarete Watzka Jennifer L. Soong Sara Vicca Ivan A. Janssens Michael Bahn 《Global Change Biology》2023,29(18):5276-5291
Climate warming has been suggested to impact high latitude grasslands severely, potentially causing considerable carbon (C) losses from soil. Warming can also stimulate nitrogen (N) turnover, but it is largely unclear whether and how altered N availability impacts belowground C dynamics. Even less is known about the individual and interactive effects of warming and N availability on the fate of recently photosynthesized C in soil. On a 10-year geothermal warming gradient in Iceland, we studied the effects of soil warming and N addition on CO2 fluxes and the fate of recently photosynthesized C through CO2 flux measurements and a 13CO2 pulse-labeling experiment. Under warming, ecosystem respiration exceeded maximum gross primary productivity, causing increased net CO2 emissions. N addition treatments revealed that, surprisingly, the plants in the warmed soil were N limited, which constrained primary productivity and decreased recently assimilated C in shoots and roots. In soil, microbes were increasingly C limited under warming and increased microbial uptake of recent C. Soil respiration was increased by warming and was fueled by increased belowground inputs and turnover of recently photosynthesized C. Our findings suggest that a decade of warming seemed to have induced a N limitation in plants and a C limitation by soil microbes. This caused a decrease in net ecosystem CO2 uptake and accelerated the respiratory release of photosynthesized C, which decreased the C sequestration potential of the grassland. Our study highlights the importance of belowground C allocation and C-N interactions in the C dynamics of subarctic ecosystems in a warmer world. 相似文献
78.
Ragnheiður Fossdal Magnus Böðarsson Páll Ásmundsson Jóhann Ragnarsson Dorien Peters Martijn H. Breuning Ólafur Jensson 《Human genetics》1993,91(6):609-613
We have mainly used 3 highly polymorphic DNA markers, 3HVR (D16S85), 16AC2.5 (D16S291) and SM7 (D16S283), flanking the PKD1 region on chromosome 16p13.3 to establish linkage status in seven Icelandic families with autosomal dominant polycystic kidney disease (ADPKD). In four families, the disease locus is in the PKD1 region, and three families are unlinked to chromosome 16p13.3. In one of the unlinked families, the disease locus is excluded from a part of the long arm of chromosome 2, and we support a theory of more than 2 loci being responsible for ADPKD. Our data confirm the location of the locus YNH24 (D2S44) to chromosome 2q13-q24. 相似文献
79.
S. Magnussen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1993,86(2-3):349-355
Summary A central problem in the analysis of genetic field trials is the dichotomy of genetic and environmental effects because one cannot be defined without the other. Results from 768,000 simulated family trials in complete randomized block designs demonstrated a serious upward bias in estimates of family variance components from multi-unit plot designs when the phenotypic observations were compatible with a first-order autoregressive (AR1) process. The inflation of family variances and, thus, additive genetic variance and narrow sense individual heritabilities progressed exponentially with an increase in the nearest neighbor correlation () in the AR1 process. Significant differences in inflation rates persisted among various plot configurations. At = 0.2 the inflation of family variances reached 48–73%. Inflation rates were independent of the level of heritability. Modified Papadakis nearest neighbor (NN) adjustment procedures were tested for their ability to remove the bias in family variances. A NN-adjustment based on Mead's coefficient of interplant interaction and one derived from Bartlett's simultaneous autoregressive scheme removed up to 97% of the bias introduced by the phenotypic correlations. NN-adjusted estimates had slightly (5–8%) higher relative errors than did unadjusted estimates. 相似文献
80.
S. Magnussen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,82(3):305-312
Summary Simultaneous improvement of several, and often negatively correlated, traits is frequently a desired objective in forest tree breeding. A profit function that includes a combination of both linear weights and weights for the cross-products of trait combinations facilitates the construction of a linear index, with an attractive response in all traits. A detailed algorithm for finding the index coefficients is provided, along with three examples of applications in tree breeding. The index is also a powerful tool in optimizing the selection for a ratio of two traits. It is argued that a more equal progress in several traits provides a safetey net when faced with economic uncertainties. The provided algorithm eliminates the need for direct search techniques. Existence of a dual set of linear weights means that the statistical properties of the index based on nonlinear profit functions are identical to those of the classical Smith-Hazel type of index. 相似文献