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Cultural and environmental factors interact in determining the genetic structure of human populations. Bio-demographic investigations of ethnic minorities are able to disentangle the influences that these two components have on the evolution of the genetic structure of a population. The ethnic minority of the Arb?reshe of the province of Cosenza (Calabria, southern Italy) is analyzed in this paper and its bio-demographic structure in the early 1800s is compared with that of neighboring Italian populations. The data derive from surnames recorded in the birth registers of the 19 Arbdreshe municipalities of the province of Cosenza and in 5 non-Arb?reshe municipalities of the same province. Isonymy and repeated pairs of surnames are used to analyze the bio-demographic structure of these populations, while analysis of isonymic relationships is used to investigate the variability between populations. Higher values of marital isonymy and subdivision into subpopulations characterize the Arb?reshe populations with respect to their non-Arb?reshe neighbors. However, the high range of variability of these parameters suggests a strong influence of geographic location on the marriage pattern of each community. At the same time, cultural differences linked to group identity had a strong impact in limiting marriage exchanges between the different ethnic groups living in the province of Cosenza in the early 1800s. In fact, the analysis of isonymic relationships demonstrates that geographic location shaped kinship patterns among the Arbereshe communities, but it also shows that the non-Arb?reshe neighbors formed a clearly separate reproductive cluster.  相似文献   

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Cathepsins D, K, and L were immunolocalized in tissue undergoing endochondral ossification in the human. Cathepsins D, K, and L were localized in osteoclasts and chondroclasts attached to bone matrix and cartilage matrix, respectively. Cathepsins D and L were immunostained in chondrocytes. Immunolocalization of cathepsin D was limited to hypertrophic chondrocytes adjacent to the osteochondral junction. In contrast, cathepsin L was immunolocalized in both proliferating and hypertrophic chondrocytes. In the bone marrow space, cathepsins D, K, and L were localized in multinucleated cells. Cathepsin D was diffusely detected in mononuclear bone marrow cells which were negative for cathepsins K and L. The present findings indicated that cathepsins K, D, and L were associated with the process of endochondral ossification in the human, and suggested that these cathepsins share roles in bone and cartilage turnover in the human.  相似文献   

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The data on the composition and abundance of nekton species and their interannual variations within the upper epipelagic layer (0–50 m) in the Aleutian and Commander basins in the western Bering Sea that are considered in the article were collected during complex surveys that were conducted by the Pacific Research Fisheries Center in September and October of 2002–2013. The core species structures of the nekton communities in these two areas were similar: the chum salmon Oncorhynchus keta and the boreopacific gonate squid Boreoteuthis borealis were the most abundant species. Simpson’s dominance index varied synchronously in both areas, with higher values in the Aleutian Basin, until 2009. In the subsequent years, the values of the index for the studied areas became equal and varied asynchronously. An analysis of abundance showed that two types of species structure most often prevailed (with the dominance of either chum salmon or squid); in some years the species structure differed from that in other years. Species of the low-boreal and low-boreal-subtropical complexes were more abundant in the Commander Basin, reaching particularly high proportions in 2006, 2008, and 2012. Certain species showed similarity in the year-to-year dynamics of their abundance; however, these coincidences were frequently accidental. After the climate regime shift in 2006–2007, the total biomass of nekton in the Aleutian Basin decreased from 3241 to 1736 kg/km2 (46%); in the Komandorskiye Basin it decreased from 2459 to 1976 kg/km2 (20%).  相似文献   

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Fennoscandia is characterized by a large degree of climatic diversity. Vegetation phenology may respond differently to climate change according to the climatic gradients within the region. To map the annual and spatial variability of the start of the growing season (SOS) in Fennoscandia, the twice-monthly GIMMS-NDVI satellite dataset was used. The data set has an 8 × 8 km2 spatial resolution and covers the period from 1982 to 2002. The mapping was done by applying pixel-specific threshold values to the NDVI data. These threshold values were determined form surface phenology data on birch (Betula sp.). Then, we produced NDVI based maps of SOS for each of the 21 years. Finally, the time differences between the SOS and the last day of snow cover, as well as dates of passing different temperatures, were analyzed for 21 meteorological stations. The analyses showed that 1985 was the most extreme year in terms of late SOS. In terms of early SOS, the year 1990 was by far the most extreme. Locally, the SOS has an average range of 1 month between the earliest and latest recorded SOS, with a trend towards a bigger range in the oceanic parts. The results indicate that a 1°C increase in spring temperatures in general corresponds to an advancement of 5–6 days in SOS. However, there is a clear trend according to the degree of oceanity, with a 1°C increase in the most oceanic parts corresponding roughly to 7–9 days earlier SOS, compared to less than 5 days earlier in the continental parts.  相似文献   

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The aim of this study was to describe spatial patterns of the distribution of leprosy and to investigate spatial clustering of incidence rates in the state of Ceará, Northeast Brazil. The average incidence rate of leprosy for the period of 1991 to 1999 was calculated for each municipality of Ceará. Maps were used to describe the spatial distribution of the disease, and spatial statistics were applied to explore large- and small-scale variations of incidence rates. Three regions were identified in which the incidence of leprosy was particularly high. A spatial gradient in the incidence rates was identified, with a tendency of high rates to be concentrated on the North-South axis in the middle region of the state. Moran's I statistic indicated that a significant spatial autocorrelation also existed. The spatial distribution of leprosy in Ceará is heterogeneous. The reasons for spatial clustering of disease rates are not known, but might be related to an heterogeneous distribution of other factors such as crowding, social inequality, and environmental characteristics which by themselves determine the transmission of Mycobacterium leprae.  相似文献   

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Labelling of Rhodobacter capsulatus cells with (32P)Pi in a phototrophic culture results in phosphorylation of a membrane-bound polypeptide identified as the subunit of the LHI antenna complex of the photosynthetic apparatus. Phosphorylation of the same polypeptide was also observed by incubation of chromatophores with (32P)ATP or under conditions of photophosphorylation with ADP and (32P)Pi. The identity of the phosphorylated LHI- subunit was demonstrated by N-terminal protein sequencing of the phosphorylated polypeptide and by failure of labelling in LHI-defective mutants. Pre-aeration of the samples or addition of the oxidant potassium ferrcyanide stimulated the kinase activity whereas the presence of soluble cytoplasmic proteins impaired phosphorylation in an in vitro assay. No effect resulted from addition of reductants to the assay medium. The results indicate the presence of a membrane-bound protein kinase in R. capsulatus that phosphorylates the subunit of the LHI antenna complex under redox control.Abbreviations Pi inorganic phosphate - SDS-PAGE sodium dodecyl-sulfate polyacrylamide gel electrophoresis  相似文献   

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Archaeobotanical investigations at Qara Qorum (Karakorum), Mongolia, reveal information about diet and land use from the 13th to the 15th century A.D. People grew Panicum miliaceum, Hordeum vulgare, Triticum aestivum and Setaria italica in nearby irrigated fields but additionally imported all other known cereals, including Oryza sativa, in small amounts as well as oil and fibre plants and pulses. The most common oil and fibre plant was Cannabis sativa. At least ten species of vegetables and spices such as Carum carvi, Coriandrum sativum, Apium graveolens, Beta vulgaris, Lycium chinense and Piper nigrum were either gathered from the wild, grown locally or imported. Apart from some wild gathered species like Pinus sibirica and Fragaria vesca, most of the fruits and nuts as for instance Vitis vinifera, Ficus carica, Ziziphus jujuba, Prunus dulcis, P. insititia, P. avium and P. persica, Cucumis melo and Juglans regia must also have been imported from quite long distances. First pollen results from lake Ugii Nuur, 50 km north of Qara Qorum indicate a much earlier beginning of agriculture than in the high and late Medieval.  相似文献   

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Concentration of osmotically active substances in the blood serum of the sturgeon A. guldenstaedti and sevruga A. stellatus from the central part of the Caspian Sea is practically equal to that in the sea water. In the blood serum of the sturgeon and the sevruga, concentration of Na is higher, whereas concentration of K and Mg is lower than in the sea water. Excretion of the urine with relatively low Mg concentration presumably indicated that being isoosmotic to the medium, the fishes studied in the Caspian Sea do not swallow the sea water. Electronmicroscopic studies indicate that with respect to poor development of membranous structures at the base of cells in the proximal tubuli, the kidney of the sturgeon and sevruga stands closer to freshwater than marine teleosts. These data show specific pattern of the osmotic and ionic regulation in the sturgeon, i.e. its isoosmotic type during migration to the Caspian Sea.  相似文献   

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Summary In light of the possible role peripheral nerves may play in bone metabolism, the morphology of calcitonin gene-related peptide (CGRP)-, vasoactive intestinal peptide (VIP)-, substance P (SP)-, neuropeptide Y (NPY)-, and dopamine--hydroxylase (DH)-immunoreactive nerve fibers was examined in whole-mount preparations of periosteum of membranous bones (calvaria, mandible) and long bones (tibia) from the rat. Periosteum from animals treated to remove selectively either the sympathetic or fine-caliber primary afferent nerves was also examined to determine the origin of the nerve fibers. We found a consistent and often dense innervation of the periosteum. The innervation patterns of the calvaria and mandible were similar, with networks of nerves spread across the surface of the bone. Nerves in the tibial periosteum were oriented in the longitudinal axis and were more numerous at the epiphyses than in the mid-shaft region. CGRP-immunoreactive fibers were widely and densely distributed. The presence of populations of CGRP-immunoreactive fibers of differing calibers and perivascular arrangements suggests that such nerves in bone tissues may serve different functions. SP-immunoreactivity was present in a fine network of varicose fibers in the superficial layers of the periosteum. CGRP- and SP-immunoreactive nerve fibers were dramatically reduced in periosteum of capsaicin-treated animals as compared to controls, indicating the sensory origin of these nerves. VIP-immunoreactive nerve fibers were distributed in the periosteum of mandible and calvaria as small networks and individual fine varicose fibers. In tibial periosteum, larger networks of these fibers were visible. VIP-immunoreactive nerve fibers in the periosteum were associated with both vascular and nonvascular elements within the layers of cells closest to the bone, suggesting that VIP may serve more than one function in periosteal tissues. NPY-immunoreactive fibers were largely confined to vascular elements; occasional fibers were observed among the bone-lining cells. DH-immunoreactivity was associated only with blood vessels. VIP-, NPY-, and DH-immunoreactivities were dramatically reduced in the periosteum of guanethidinetreated animals, indicating the sympathetic origin of these nerves.  相似文献   

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A critical and annotated catalogue of 183 types of Hymenoptera Chrysididae belonging to 124 taxa housed in the Radoszkowski collection is given. Radoszkowski type material from other institutes has also been checked. Six lectotypes are designated in Kraków (ISEA-PAN): Chrysis acceptabilis Radoszkowski, 1891; Chrysis persica Radoczkowsky, 1881; Chrysis daphnis Mocsáry, 1889; Chrysis lagodechii Radoszkowski, 1889; Chrysis remota Mocsáry, 1889 and Chrysis vagans Radoszkowski, 1877. The lectotype of Brugmoia pellucida Radoszkowski, 1877 is designated in Moscow (MMU). Four new combinations are proposed: Philoctetes araraticus (Radoszkowski, 1890), comb. n.; Pseudomalus hypocrita (du Buysson, 1893), comb. n.; Chrysis eldari (Radoszkowski, 1893), comb. n.; and Chrysura mlokosewitzi (Radoszkowski, 1889), comb. n.. Ten new synonyms are given: Chrysis auropunctata Mocsáry, 1889, syn. n. of Chrysis angolensis Radoszkovsky, 1881; Chrysis chrysochlora Mocsáry, 1889, syn. n. and Chrysis viridans Radoszkowski, 1891, syn. n. of Chrysis keriensis Radoszkowski, 1887; Chrysis angustifrons var. ignicollis Trautmann, 1926, syn. n. of Chrysis eldari (Radoszkowski, 1893); Chrysis maracandensis var. simulatrix Radoszkowski, 1891, syn. n. of Chrysis maracandensis Radoszkowski, 1877; Chrysis pulchra Radoszkovsky, 1880, syn. n. of Spinolia dallatorreana (Mocsáry, 1896); Chrysis rubricollis du Buysson, 1900, syn. n. of Chrysis eldari (Radoszkowski, 1893); Chrysis subcoerulea Radoszkowski, 1891, syn. n. of Chrysis chlorochrysa Mocsáry, 1889; Chrysis therates Mocsáry, 1889, syn. n. of Chrysis principalis Smith, 1874; and Notozus komarowi Radoszkowski, 1893, syn. n. of Elampus obesus (Mocsáry, 1890). One species is revaluated: Chrysis chalcochrysa Mocsáry, 1887. Chrysis kizilkumiana Rosa is the new name for Chrysis uljanini Radoszkowski & Mocsáry, 1889 nec Radoszkowski, 1877. Pictures of seventy-seven type specimens are given.  相似文献   

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Lieber MR  Lu H  Gu J  Schwarz K 《Cell research》2008,18(1):125-133
Nonhomologous DNA end joining (NHEJ) is the primary pathway for repair of double-strand DNA breaks in human cells and in multicellular eukaryotes. The causes of double-strand breaks often fragment the DNA at the site of damage, resulting in the loss of information there. NHEJ does not restore the lost information and may resect additional nucleotides during the repair process. The ability to repair a wide range of overhang and damage configurations reflects the flexibility of the nuclease, polymerases, and ligase of NHEJ. The flexibility of the individual components also explains the large number of ways in which NHEJ can repair any given pair of DNA ends. The loss of information locally at sites of NHEJ repair may contribute to cancer and aging, but the action by NHEJ ensures that entire segments of chromosomes are not lost.  相似文献   

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Summary The distribution of -melanocyte-stimulating hormone (-MSH) was studied in the brain of the lizard Lacerta muralis by means of immunocytochemical staining methods. -MSH-like containing cells were found in the ventro-lateral preoptic area and the paraventricular and supraoptic nuclei. Some scattered cells staining for -MSH were also detected in the mesencephalo-diencephalic boundary region, while numerous -MSH-like nerve fibres were localized in the medial eminence. No reaction was observed after the use of antiserum preabsorbed with synthetic antigen.These findings suggest that an -MSH-like peptidergic system could possibly be involved in the hypothalamo-hypophysial regulation and/or play a role as neurotransmitter in this animal.  相似文献   

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The Greater White-toothed shrew Crocidura russula is short-lived species and the phase of senescence is greatly elongated in captivity. The loss of rhythmicity of biological functions that accompanies its aging is also well documented. C. russula is thus an excellent model to test the effects of aging on biological clocks. Melatonin is a key hormone in the synchronization of behaviors, metabolisms and physiological regulations with environmental factors. In the present work we want to know if the loss of rhythmicity and the reduced melatonin levels registered by the second year of life in this species could be associated to modified ultrastructural features of the pineal parenchyma, site of melatonin synthesis. Transmission electron microscopy (TEM) analysis of young (1-4 months) and old (25-28 months) shrew's pineals show that in older individuals, the parenchyma undergoes alterations affecting mainly nucleus, mitochondria and endoplasmic reticulum cisternae, with increased numbers of dense bodies and the formation of many concretions as well as a depletion of secretory products. These changes suggest a process of slowing pinealocytes metabolism which could explain the gradual reduction of melatonin levels registered during aging in C. russula.  相似文献   

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Historical collections held in ancient archives and libraries constitute a cultural and artistic heritage of inestimable value. These collections contain a series of organic materials which may alter and perish in time, especially if they are conserved in inadequate environmental conditions and without any specific precautionary devices to protect them from damage caused by chemical, biological and physical factors. It is essential to prevent ‘at risk’ situations to conserve library and archive heritage. Early detection of fungal spores and moulds in conservation environments will permit us to intervene at the infection site at the right moment and also to detect the micro‐environments where climatic parameters are not suitable for conservation purposes.

The aim of this study is to examine potentially biodeteriogen fungal micro‐flora in the environment of the “Doctorate Library”, one of the most important buildings of the University of Perugia, which contains frescos and library collection of great value. The study was carried out through quantitative and qualitative analysis of airborne fungal species and through the evaluation of viable aerobiological particles as potential agents of biodeterioration. The airspore monitoring was made using the active method (by Personal Volumetric Air Sampler Spore Trap, Burkard Company Ltd.) and the passive one (by sedimentation technique on Petri dishes). The results obtained by both methods allowed us to detect numerous potentially biodeteriogen species, to determine their quantity and influence and to evaluate the levels of their variability in time.  相似文献   

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