Spatial dynamics and expanded vertical niche of blue sharks in oceanographic fronts reveal habitat targets for conservation

Dramatic population declines among species of pelagic shark as a result of overfishing have been reported, with some species now at a fraction of their historical biomass. Advanced telemetry techniques enable tracking of spatial dynamics and behaviour, providing fundamental information on habitat preferences of threatened species to aid conservation. We tracked movements of the highest pelagic fisheries by-catch species, the blue shark Prionace glauca, in the North-east Atlantic using pop-off satellite-linked archival tags to determine the degree of space use linked to habitat and to examine vertical niche. Overall, blue sharks moved south-west of tagging sites (English Channel; southern Portugal), exhibiting pronounced site fidelity correlated with localized productive frontal areas, with estimated space-use patterns being significantly different from that of random walks. Tracked female sharks displayed behavioural variability in diel depth preferences, both within and between individuals. Diel depth use ranged from normal DVM (nDVM; dawn descent, dusk ascent), to reverse DVM (rDVM; dawn ascent, dusk descent), to behavioural patterns where no diel differences were apparent. Results showed that blue sharks occupy some of the most productive marine zones for extended periods and structure diel activity patterns across multiple spatio-temporal scales in response to particular habitat types. In so doing, sharks occupied an extraordinarily broad vertical depth range for their size (1.0-2.0 m fork length), from the surface into the bathypelagic realm (max. dive depth, 1160 m). The space-use patterns of blue sharks indicated they spend much of the time in areas where pelagic longlining activities are often highest, and in depth zones where these fisheries particularly target other species, which could account for the rapid declines recently reported for blue sharks in many parts of the world's oceans. Our results provide habitat targets for blue shark conservation that may also be relevant to other pelagic species.     

Spatial distribution and features of biology of Pacific sleeper shark Somniosus pacificus in the North Pacific

The results of the investigations of spatial and vertical distribution of Pacific sleeper shark Somniosus pacificus in the North Pacific Ocean conducted for many years are presented. In addition, the size distribution and features of biology of the species are studied. The largest abundance of the species is registered in the Bering Sea, western Gulf of Alaska, eastern Aleutian Islands, and Pacific waters of northern Kuril Islands and southeastern Kamchatka. The species is the most abundant near the bottom at the depth from 200 to 700 m and in the pelagic waters at a depth of 100–200 m. The average depths of the catches of Pacific sleeper shark substantially change over the year reaching minimum values in June and maximum values in December. Vertical daily migrations (to the water column at night and to the bottom during the day) are registered. The catches are represented by fish 26–352 cm in length, and sharks 100–200 cm in length prevail. The males are noticeably smaller than the females. In general, condition of the fishes decreases and feeding intensity increases with growth. Food composition substantially changes with the increase of body length: consumption of squids decreases and consumption of crustaceans, fishes, and fishery wastes increases. The food composition is slightly different in the females and males.     

Spatial distribution of chlorophyll a and its relationship with the environment during summer in Lake Poyang: a Yangtze-connected lake

Lake Poyang, a Yangtze-connected lake that is the largest freshwater lake in China, was studied in summer from 2009 to 2012. The primary objective was to investigate the spatial variability of chlorophyll a (chl a) on a whole-lake scale and to identify the key factors affecting phytoplankton growth. Stepwise multiple linear regression and Spearman’s rank correlation analyses showed that the shade index is the major factor determining the spatial distribution of chl a; nutrients don’t explain much variation in chl a, except in the east. The relationships between shade index and chl a varied regionally. Chl a varied inversely with the variation of the shade index, especially in the north and south, reflecting light limitation. However, the correlation was positive in the east due to high chl a concentration negatively affecting light availability, which was promoted by sufficient nutrients. In the center, no factor was found to have an obvious effect on phytoplankton growth, most likely because of human activities and high heterogeneity. These new data on the spatial variability of chl a and its relationship with light availability in Lake Poyang will be crucial to understand chl a regulation and contribute to the knowledge regarding phytoplankton in the Yangtze Basin.     

黄海中南部越冬鳀鱼空间分布及其与水温年际变化的关系

利用1986-2010年的底拖网调查数据和遥感海表温度,基于GIS技术,通过空间分析和相关性分析等方法,研究黄海中南部水域越冬鳀鱼空间分布的年际变化,并探讨其与水温变化的关系.结果表明:1986-2010年鳀鱼空间分布的年际变化明显,2004年其资源丰度下降至最低且向岸分布,2010年资源丰度有所回升并在东部水域集中分布,鳀鱼捕获站位、资源密度在经纬度方向上的分布集中区域年际变化明显;鳀鱼资源密度重心纬度与代表性等温线平均纬度的变化趋势相一致,表明水温变化影响越冬鳀鱼纬度方向上的分布,但其向岸分布趋势则由黄海暖流的年际变动决定;在影响鳀鱼分布的众多因子中,资源丰度变化主要受捕捞压力的影响,而空间上的变化主要由海水温度决定.     

Psychometric analysis of behavior pattern A in the Spanish population and its relationship with personality variables

As a first step in the epidemiological study for CHD prevention among the Spanish population, the authors have analyzed two of the instruments for the assessment of the behavior pattern A (JAS and Bortner questionnaires). From a student sample (n = 302), a factor analysis of items and scales was made, relating pattern A scores to Eysenck's personality variables (EPQ). The importance of an accurate psychometric study of pattern A was emphasized, in order to select A subjects as specifically as possible.     

Occurrence and distribution of tomato seed-borne mycoflora in Saudi Arabia and its correlation with the climatic variables

One hundred samples of tomato seeds were collected in 2011 and 2012 from tomato-cultivated fields in Saudi Arabia and screened for their seed-borne mycoflora. A total of 30 genera and 57 species of fungi were recovered from the collected seed samples using agar plate and deep-freezing blotter methods. The two methods differed as regards the frequency of recovered seed-borne fungi. Seven fungi among those recovered from tomato seeds, which are known as plant pathogens, were tested for their pathogenicity and transmission on tomato seedlings. The recovery rate of these pathogens gradually decreased from root up to the upper stem, and did not reach to the stem apex. The distribution of tomato seed-borne fungi was also investigated throughout Saudi Arabia. In this concern, Al-Madena governorate recorded the highest incidence of fungal flora associated with tomato seeds. The impact of meteorological variables on the distribution of tomato seed-borne mycoflora was explored using the ordination technique (canonical correspondence analysis). Among all climatic factors, relative humidity was the most influential variable in this regard. Our findings may provide a valuable contribution to our understanding of future global disease change and may be used also to predict disease occurrence and fungal transfer to new uninfected areas.     

Spatial and temporal distribution of coho salmon carcasses in a stream in the Pacific Northwest,USA

During two consecutive spawning seasons, the movement and distribution of naturally occurring coho salmon (Oncorhynchus kisutch) carcasses were monitored, and the effectiveness of large woody debris (LWD) in retaining carcasses in a stream was evaluated. In both seasons studied, the proportion of carcasses trapped by LWD increased as the season progressed. Densities of salmon carcasses were higher in slow waters such as stream edges and backwaters throughout the study periods. The average distance drifted by carcasses was 19.5m in the first season and 32.1 m in the second season. These results support the notion that LWD contributes to retention of salmon carcasses and enhances availability of salmon-derived nutrients for organisms near salmon spawning grounds.     

Spatial structure in lotic macroinvertebrate communities in England and Wales: relationship with physical, chemical and anthropogenic stress variables

We describe the relationship between macroinvertebrate community composition, the physicochemical environment and anthropogenic impacts, in running water sites across a range of water qualities in England and Wales. We have also investigated the degree of spatial structure present in both the macroinvertebrate community and the measured environment. Selected explanatory variables could account for 26% of the variation in lotic macroinvertebrate assemblage composition across England and Wales. The explanatory power of the CCA model was based predominantly on a combination of local scale variables (substrate, alkalinity, urban run-off) and regional scale variables (discharge category, northing). The physicochemical gradient associated with changes in stream type from headwaters to estuary dominated assemblage composition. The influence of pollution and habitat modification were of secondary importance. There was a substantial level of spatial structure to both the physicochemical (47% of its explanatory power spatially structured) and anthropogenic stress data (63% of its explanatory power spatially structured), which resulted in a high level of predictable spatial structuring in macroinvertebrate assemblages. Almost 40% of the variation in assemblage composition accounted for by the explanatory model exhibited spatial structure. Positive spatial autocorrelation in macroinvertebrate community composition extended to sites up to 150km apart. As a consequence, community composition could be described from northing and easting with 75% of the explanatory power of the eight physicochemical variables. Our study has confirmed the importance of the longitudinal gradient within catchments, as well as the geographical position of the catchment to macroinvertebrate communities. We have also demonstrated how quantifying the spatial structure in the dataset can improve our understanding of the factors influencing macroinvertebrate community structure.     

Diversity of terrestrial gastropod mollusks in the Pacific region of Nicaragua, and their habitat preferences

Diversity of terrestrial gastropod mollusks in the Pacific region of Nicaragua, and their habitat preferences. Landsnail communities of the Nicaraguan Pacific Slope were studied. The study area was subdivided into 21 quadrats (ca. 40 x 40 km). A high taxonomic richness was found: 79 species, 43 genera and 23 families. Species richness (S) per quadrat ranged from 17 through 50. The biogeographic index presented higher values on quadrats 5 (3.04), 6 (3.03), 8 (2.96) and 11(2.96). Quadrat 11 had the highest species richness (S=50), and one of the highest biogeographic index values (IB=2.96). Gastropod mollusk communities are favored by sites with an illumination of filtered sun, associated to riparian forests and with a susbtratum of wet soils and leaf litter.     

The distribution of IGF2 and IMP3 in osteosarcoma and its relationship with angiogenesis

The aim of this study was to investigate the expression patterns of IGF2 and IMP3 in osteosarcoma as well as its relationship with angiogenesis in the tumor. IGF2 and IMP3 expression was detected by immunohistochemical staining in the serial sections of the osteosarcoma. The impacts of IGF2 and IMP3 expression patterns on tumor angiogenesis were evaluated by statistics. The IGF2 and IMP3 staining had different expression patterns in different osteosarcoma. Twelve out of the sixty-four cases of conventional osteosarcoma showed nuclear staining patterns, and twenty-nine showed cytoplasmic staining of IGF2 and IMP3 simultaneously. On the other hand, fourteen cases showed nuclear IGF2 staining but cytoplasmic IMP3 expression, and nine cases showed nuclear IMP3 staining and cytoplasmic IGF2 expression. Twenty-eight out of forty-seven cases of parosteal osteosarcoma showed nuclear IGF2 and IMP3 expression, nine showed cytoplasmic IGF2 and IMP3 expression simultaneously. Seven out of forty-seven cases of parosteal osteosarcoma expressed IGF2 with nuclear staining but expressed IMP3 with cytoplasmic staining. Meanwhile, three cases expressed IGF2 with cytoplasmic staining but expressed IMP3 with nuclear staining. Similar to the parosteal osteosarcoma, the periosteal osteosarcoma expressed IGF2 and IMP3 mainly with nuclear staining simultaneously, forty out of fifty-five cases of periosteal osteosarcoma did that. Five out of fifty-five cases expressed IGF2 and IMP3 with cytoplasmic staining at the same time. Four cases showed nuclear IGF2 staining and cytoplasmic IMP3 staining. In the parosteal and periosteal osteosarcoma, there was no significant difference in IGF and IMP3 expression patterns (P = 0.216). However, compared with conventional osteosarcoma, the parosteal and periosteal osteosarcoma showed significant difference in IMP3 and IGF2 expression (P = 0.016, P = 0.023). IGF2 and IMP3 expression patterns were positive correlation in the different osteosarcoma (r = 0.1021, P = 0.032). The Microvessel density (MVD) in osteosarcoma with IGF2 and IMP3 cytoplasmic staining was more than that with nuclear expression of IGF2 and IMP3, and the difference was significant (P = 0.024). Moreover, the conventional osteosarcoma with cytoplasmic IGF and IMP3 showed more MVD than parosteal and periosteal osteosarcoma with cytoplasmic IGF and IMP3, and the difference was significant (P = 0.035). IGF2 and IMP3 had different expression patterns, which might be associated with angiogenesis. However, cytoplasmic and nuclear expression of IGF2 and IMP3 might play different roles in the angiogenesis of osteosarcoma.     

Meroplankton distribution in the central Barents Sea in relation to local oceanographic patterns

Abundance and spatio-temporal distribution of meroplankton (larvae of invertebrate benthos) in the central Barents Sea and their dependence on abiotic factors were investigated. Samples were taken in different depth intervals on a south-north transect in the marginal ice zone in May 1997. At several locations sampling was repeated in June 1997. In May, total meroplankton abundances varied between 0.1 ind. m^-3 and 32.0 ind. m^-3, but mainly fluctuated around 10-15 ind. m^-3. They were strongly affected by the mass occurrence of single species. At the northern, heavily ice-covered stations numbers decreased significantly. Larvae of 27 types were found. Polychaetes represented the most diverse group (13 species), followed by echinoderms (8 species). Larvae of only one bivalve species were found (Mya truncata), but with very high abundances (86 ind. m^-3). Other taxa were represented only by single specimens. In June, total abundances were similar. The same species were present but the distribution patterns were less distinct, diversity values were higher and most larvae were further developed than in May. Distribution patterns of the larvae were to a large extent determined by physical processes in the area of the Polar Front, which acted as a distinct barrier in surface waters. In May, four meroplankton assemblages were distinguished, each associated with a different water mass. Most of the larvae have also been found in other investigated Arctic areas and belong to species with an Atlantic-Boreal-Arctic or Boreal-Arctic distribution. The relatively high numbers of larval types found in this study indicate that indirect development with pelagic larval stages plays a role in benthic recruitment in this sub-Arctic region. The relevance of these observations for the so-called Thorson rule is discussed.     

Dynamic distribution of Spatial during mouse spermatogenesis and its interaction with the kinesin KIF17b

The Spatial gene is expressed in highly polarized cell types, such as epithelial cells in the thymus, neurons in the brain and germ cells in the testis. In this study, we report the characterization and distribution of Spatial proteins during mouse spermatogenesis. Besides Spatial-epsilon and -delta, we show that the newly described short isoform Spatial-beta is expressed specifically in round spermatids. Using indirect immunofluorescence, we detected Spatial in the cytosol of the early round spermatid. By the end stages of round spermatids, Spatial is concentrated at the opposite face of the acrosome near the nascent flagellum and in the manchette during the elongation process. Finally in mature sperm, Spatial persists in the principal piece of the tail. Moreover, we found that Spatial colocalizes with KIF17b, a testis-specific isoform of the brain kinesin-2 motor KIF17. This colocalization is restricted to the manchette and the principal piece of the sperm tail. Further, coimmunoprecipitation experiments of native proteins from testis lysates confirmed Spatial-KIF17b association through the long Spatial-epsilon isoform. Together, these findings imply a function of Spatial in spermatid differentiation as a new cargo of kinesin KIF17b, in a microtubule-dependent mechanism specific to the manchette and the principal piece of the sperm tail.     

Dynamics of the distribution of variables in morphology

This paper discusses examples of exponentially distributed, Poisson-distributed, and binomially distributed random variables from morphology and describes secular and historical processes as well as phenomena of aging as factors of the dynamics of such distributions, the major focus being on tests of morphometric variables for the existence of normal distributions. In those cases where hypotheses of the existence of particular distributions of random morphometric variables are established it is necessary that consideration be given to metrological and stereological factors pertaining to the process of measuring and the geometry of the structures being measured, respectively. Karyometric results are used to demonstrate the splitting of a single statistical population into several populations as a result of the process of aging of the human organism.