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1.
The identification of the presence of genotype by environment interaction effects on important traits in Holstein cattle allows for the use of international genetic evaluations and a more efficient design of regional genetic evaluation programmes. The aim of this study was to determine the genotype × environment interaction effects in Chilean Holstein dairy cattle through the analysis of records corresponding to calvings between 1998 and 2015. Herds were classified in the central and southern regions of Chile based on herd location as well as by high and low levels of production environments based on the fat plus protein yield averages per herd within each region. The central region has a Mediterranean climate and a confined production system while the southern region has a humid temperate climate and a production system based on grazing with supplementation. Traits studied were milk yield (MY), fat yield (FY), protein yield (PY), fat content (FC) and protein content (PC) by lactation, age at first calving (AFC) and calving interval (CI). Several four-trait mixed animal models were applied to environmental category data as different traits, which included herd-year-calving season (herd-year-birth season for AFC) and lactation number as fixed effects, and animal additive genetic, sire-herd, permanent environment and residual effects as random effects. Genetic correlations (rg) for MY, FY, FC, PC and CI were found to decrease as differences between environmental categories increased. The rg between the most extreme environmental categories considered in this study for AFC (0.26) was the only one found statistically lower than 0.60. Genetic correlation values statistically lower than 0.80 (P < 0.05) were observed for AFC, CI, MY, FY and PY between some environmental categories. If separate genetic evaluations are adopted as practical criteria when the value of rg is lower than 0.60, the consequence of improving a multi-trait economic breeding objective in this population is likely to be small unless extreme environmental categories are considered. However, a moderate decrease in selection response and re-ranking of selection candidates is expected for AFC, CI and yield traits when selection is performed in different environmental conditions. Genotype × environment interaction effects involving production systems in a Mediterranean climate and confinement vs. Temperate Oceanic climate and grazing with supplementation, and between two fat plus protein yield level categories within each environment, were at most moderate for the studied traits.  相似文献   

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The aim of this study is to evaluate microMOSFET as in-vivo dosimeter in 6 MV shaped-beam radiosurgery for field sizes down to 6 × 6 mm2. A homemade build-up cap was developed and its use with microMOSFET was evaluated down to 6 × 6 mm2. The study with the homemade build-up cap was performed considering its influence on field size over-cover occurring at surface, achievement of the overall process of electronic equilibrium, dose deposition along beam axis and dose attenuation. An optimized calibration method has been validated using MOSFET in shaped-beam radiosurgery for field sizes from 98 × 98 down to 18 × 18 mm2. The method was detailed in a previous study and validated in irregular field shapes series measurements performed on a head phantom. The optimized calibration method was applied to microMOSFET equipped with homemade build-up cap down to 6 × 6 mm2. Using the same irregular field shapes, dose measurements were performed on head phantom. MicroMOSFET results were compared to previous MOSFET ones. Additional irregular field shapes down to 8.8 × 8.8 mm2 were studied with microMOSFET. Isocenter dose attenuation due to the homemade build-up cap over the microMOSFET was near 2% irrespective of field size. Our results suggested that microMOSFET equipped with homemade build-up cap is suitable for in-vivo dosimetry in shaped-beam radiosurgery for field sizes down to 6 × 6 mm2 and therefore that the required build-up cap dimensions to perform entrance in-vivo dosimetry in small-fields have to ensure only partial charge particle equilibrium.  相似文献   

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The extracellular domain of the HER-2 (ERBB2) oncoprotein (p105HER-2, ECD HER-2) is shed in the serum and can be detected by immunoassay. The currently approved cutoff for an elevated HER-2 ECD is greater than 15 ng/mL. HER-2 ECD is attractive as a potentially useful serum biomarker. In metastatic breast cancer, serum assay of HER-2 ECD is recommended to assess HER-2 status when unknown in primary tumor or metastatic biopsy is not feasible. In that case, it has been recommended to consider a 50 ng/mL serum HER-2 ECD cutoff as criteria to select patients for HER-2 targeted therapy. It might offer additional prognostic or predictive value compared with HER-2 tumor tissue testing. In addition, it can be measured serially and might be able to monitor treatment response, predict relapse or provide a real-time assessment of HER-2 status at metastatic disease.  相似文献   

7.
《L'Anthropologie》2018,122(3):415-436
The fragments of the figurine called “lion-man” were found in 1939 in the cave of Hohlenstein-Stadel, in southwestern Germany. Joachim Hahn was the first to assemble the figure in 1969; the statuette was then restored between 1987 and 1988 in the workshops of the regional museum of Württemberg in Stuttgart. New excavations, conducted by the State Office for Cultural Heritage of Baden-Württemberg (Esslingen, Germany), were held in the same cave between 2009 and 2013. Then, hundreds of small fragments were found; some of them clearly belonged to the lion-man. Following these excavations, a second restoration was undertaken in the workshops of the State office of Cultural Heritage in 2012 and 2013. The Lion-Man, the tallest of the figures from the last Ice Age, got a new appearance. After the refitting of the fragments, a large part of the figurine has been completed.  相似文献   

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Knowledge about vitamin D has greatly improved during the last few years. Vitamin D cannot any more be considered as exclusively necessary to prevent ricket/osteomalacia. Its role in the prevention of some osteoporotic fractures in the elderly (in association with calcium nutrition) is now well-demonstrated and many epidemiologic and laboratory data argue for a role in the prevention of several diseases or anomalies (cancer, auto-immune diseases, cardiovascular events, sarcopenia…). A few intervention studies confirming some of these effects also exist. Vitamin D status can easily be assessed by measuring serum 25-OH vitamin D level. However, many experts have claimed that the population-based reference values for 25OHD are too low and that the cut-off value below which vitamin D insufficiency can be present is somewhere between 20 and 40 ng/mL with a clear tendency to target values above 30 ng/mL (75 nmol/L). The main consequences are that vitamin D insufficiency is highly frequent whereas the currently recommended supplementation doses are not sufficient.  相似文献   

10.
This study aimed to assess the relationship of 3 spectrin repeat containing nuclear envelope protein 1 (SYNE1) and 4 KH domain containing RNA binding (QK1) single nucleotide polymorphisms (SNPs), their haplotypes, gene-gene (G × G), gene-environment (G × E) interactions and hypercholesterolaemia (HCH) and hypertriglyceridaemia (HTG) in the Chinese Maonan minority. The genetic make-up of the SYNE1-QK1 SNPs in 1932 unrelated subjects (normal, 641; HCH, 649; and HTG, 642) was obtained by next-generation sequencing technologies. The genotypic frequencies of following SNPs were suggestively distinctive between the control and HCH groups (rs2623963, rs7745725, rs9459317, rs16897566), or between the control and HTG groups (rs2623963, rs1358317, rs7745725, rs1923608, rs16897566 SNPs; P < .05, respectively). Multiple-locus linkage disequilibrium analysis indicated that the identified SNPs were not inherited independently. Several haplotypes and gene-gene interaction haplotypes among the detected SNPs may be related with an increased morbidity of HCH (C-G-A, C-G-G and C-G-G-T-C-A-T) and HTG (C-G-G, G-T-G-C, C-G-G-G-T-G-C and C-G-G-T-C-A-T), whereas others may be related with an decreased risk of HCH (G-A-A, G-C-A-T, C-A-A-T-C-A-T and G-A-A-G-C-A-T) and HTG (G-A-A, G-C-A-T, C-A-A-T-C-A-T and G-A-A-G-C-A-T). The association evaluation based on haplotypes and gene-gene interactions could improve the power of detecting the risk of dyslipidaemia than anyone of SNP alone. There was significant three-locus model involving SNP-SNP, haplotype-haplotype/environment and G × G interactions (P < .05-0.001) that were detected by GMDR in HCH and HTG groups. Different interactions between genetic and environmental factors would produce different redundancy or synergy effects on the morbidity of HCH and/or HTG.  相似文献   

11.
The presence of the genus Cuon during the Pleistocene of Java is attested by the endemic species C. sangiranensis and C. crassidens, sometimes classified as C. alpinus, a species that is also part of the Holocene fauna and has persisted until today. The current study revises the fossil canid material from the Sangiran Dome, previously assigned variously to C. sangiranensis, C. crassidens, C. alpinus, C. javanicus, and C. trinilensis. It aims to reinvestigate the arrival of Cuon in Java, in particular in relation to the late early Pleistocene endemic canid of Java: the Cuon-sized Xenocyon trinilensis, which had evolved in situ on Java from the large X. merriami, and which could be a potential competitor to early Cuon in case of contemporaneity. We found that a mandible fragment from Pandejan (holotype of C. crassidens) shows a morphology typical for C. alpinus. However, a maxilla and a mandible from the Bapang Formation at Sangiran, including the holotype of C. sangiranensis, is here assigned to the early dhole species C. priscus. Our results indicate that Cuon was already present in Java during the early middle Pleistocene and probably arrived as part of the immigration events during the Kedung Brubus faunal stage. Since X. trinilensis and Cuon are both hypercarnivorous medium-sized dogs, similar ecological niches are expected for both species. Thus, X. trinilensis probably was outcompeted and replaced by C. priscus. In turn, the latter species was replaced by the extant species, C. alpinus, during the Nangdong faunal stage, likely as part of the next immigration phase, which then disappeared during the tropical rainforest fauna of the Punung faunal stage and re-entered at the onset of the Holocene.  相似文献   

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During the last years, an international debate about the concept of “Palaeolithic art” has taken place. On one hand, several specialists have critiqued the use of the concept of “art” in naming the images created by Homo sapiens during the Palaeolithic era. They claim that the use of this term implies the projection of a modern category to a world - that of prehistoric humans - which is completely different from our own. On the other hand, some archaeologists consider that the term “Palaeolithic art” does not imply an anachronistic interpretation of prehistoric representations. In presenting the historical context, which has made such a discussion possible, we consider the causes and effects of this controversy. Firstly, we analyze the traditional interpretation, which considered Palaeolithic images as “works of art”. Secondly, we examine the connections, which can be found between the debate about “Palaeolithic art” and certain polemics, which have arisen from the history of art and anthropological frameworks. Thirdly, we consider the arguments utilized by those who are for and those who are against the term “Palaeolithic art”. Finally, we emphasize the importance of this debate to better understand the categories and the concepts, which determine the scientific practice.  相似文献   

20.
The c-Jun N-terminal kinase (JNK) pathway forms part of the mitogen-activated protein kinase (MAPK) signaling pathways comprising a sequential three-tiered kinase cascade. Here, an upstream MAP3K (MEKK1) phosphorylates and activates a MAP2K (MKK4 and MKK7), which in turn phosphorylates and activates the MAPK, JNK. The C-terminal kinase domain of MEKK1 (MEKK-C) is constitutively active, while MKK4/7 and JNK are both activated by dual phosphorylation of S/Y, and T/Y residues within their activation loops, respectively. While improvements in the purification of large quantities of active JNKs have recently been made, inadequacies in their yield, purity, and the efficiency of their phosphorylation still exist. We describe a novel and robust method that further improves upon the purification of large yields of highly pure, phosphorylated JNK1β1, which is most suitable for biochemical and biophysical characterization. Codon harmonization of the JNK1β1 gene was used as a precautionary measure toward increasing the soluble overexpression of the kinase. While JNK1β1 and its substrate ATF2 were both purified to >99% purity as GST fusion proteins using GSH-agarose affinity chromatography and each cleaved from GST using thrombin, constitutively-active MEKK-C and inactive MKK4 were separately expressed in E. coli as thioredoxin-His6-tagged proteins and purified using urea refolding and Ni2+-IMAC, respectively. Activation of JNK1β1 was then achieved by successfully reconstituting the JNK MAPK activation cascade in vitro; MEKK-C was used to activate MKK4, which in turn was used to efficiently phosphorylate and activate large quantities of JNK1β1. Activated JNK1β1 was thereafter able to phosphorylate ATF2 with high catalytic efficiency.  相似文献   

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