Genetic improvement on Chinese shrimp (Fenneropenaeus chinensis): growth and viability performance in F1 hybrids of different populations

Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No.1 (HH1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan's Multiple Range Test. The results show that the survival rate of JK98(a (TM) Euro)xWKN(a (TM),) was the highest, followed by WYP(a (TM) Euro)xWKN(a (TM),), FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xFKN(a (TM),); the body weight of FKN(a (TM) Euro)sxHH1(a (TM),) was the highest, followed by FKN(a (TM) Euro)xWYP(a (TM),), WYP(a (TM) Euro)xWKN(a (TM),), WYP(a (TM) Euro)xFKN(a (TM),) and JK98(a (TM) Euro)xWKN(a (TM),); the total length had the same ranking as the body weight. All growth traits in hybrids JK98(a (TM) Euro)xWKN(a (TM),) were the lowest among all combinations. F1 hybrids had significant difference (P < 0.05) in BL, CL, HST, LL, and BW; and insignificant difference (P > 0.05) in other growth traits and survival rate. The results of Duncan's Multiple Range Test are that BL and CL of JK98(a (TM) Euro)xWKN(a (TM),) were significantly different from the other combinations; HST different from the combination of FKN(a (TM) Euro)xWYP(a (TM),), FKN(a (TM) Euro)xHH1(a (TM),) and WYP(a (TM) Euro)xWKN(a (TM),); and BW different from FKN(a (TM) Euro)xWYP(a (TM),) and FKN(a (TM) Euro)xHH1(a (TM),). As a whole, the results indicate that the FKN(a (TM) Euro)xHH1(a (TM),) was the best combination in all growth traits. Therefore, hybridization can introduce the variation to base populations. The systematic selection program based on additive genetic performance may be more effective than crossbreeding.

Genetic diversity and historical population structure of Schizopygopsis pylzovi (Teleostei : Cyprinidae) in the Qinghai-Tibetan Plateau

1. Complete sequences of 1140 base pair of the cytochrome b gene from 133 specimens were obtained from nine localities including the inflow drainage system, isolated lakes and outflow drainage system in Qinghai-Tibetan Plateau to assess genetic diversity and to infer population histories of the freshwater fish Schizopygopsis pylzovi.2. Nucleotide diversities (pi) were moderate (0.0024-0.0045) in populations from the outflow drainage system and Tuosuo Lake, but low (0.0018-0.0021) in populations from Qiadam Basin. It is probable that the low intra-population variability is related with the paleoenvironmental fluctuation in Qiadam Basin, suggesting that the populations from Qiadam Basin have experienced severe bottleneck events in history.3. Phylogenetic tree topologies indicate that the individuals from different populations did not form reciprocal monophyly, but the populations from the adjacent drainages cluster geographically. Most population pairwise F-ST tests were significant, with non-significant pairwise tests between Tuosu Lake and Tuosuo Lake in the north-west of the Qinghai-Tibetan Plateau. Analysis of molecular variance (AMOVA) indicates that the significant genetic variation was explained at the levels of catchments within and among, not among specific boundaries or inflow and outflow drainage systems.4. The nested clade phylogeographical analysis indicates that historical processes are very important in the observed geographical structuring of S. pylzovi, and the contemporary population structure and differentiation of S. pylzovi may be consistent with the historical tectonic events occurred in the course of uplifts of the Qinghai-Tibetan Plateau. Fluctuations of the ecogeographical environment and major hydrographic formation might have promoted contiguous range expansion of freshwater fish populations, whereas the geological barriers among drainages have resulted in the fragmentation of population and restricted the gene flow among populations.5. The significantly large negative F-s-value (-24.91, P < 0.01) of Fu's F-s-test and the unimodal mismatch distribution indicate that the species S. pylzovi underwent a sudden population expansion after the historical tectonic event of the Gonghe Movement.6. The results of this study indicate that each population from the Qinghai-Tibetan Plateau should be managed and conserved separately and that efforts should be directed towards preserving the genetic integrity of each group.

Population dynamics and responses to management of plateau pikas Ochotona curzoniae

1. Plateau pikas Ochotona curzoniae are considered a pest species on the Tibetan Plateau because they compete with livestock for forage and their burrowing could contribute to soil erosion. The effectiveness of pest control programmes in Tibet has not been measured, and it is not known whether changes in livestock management have exacerbated problems with plateau pikas or compromised their control. This study measured the impact of control programmes and livestock management for forage conservation on populations of plateau pikas in alpine meadow in Naqu District, central Tibet, during 2004 and 2005.2. Current techniques for controlling plateau pikas in spring cause large reductions in abundance, but high density-dependent rates of increase result in no differences between treated and untreated populations by the following autumn. Rates of increase from spring to autumn are not influenced by standing plant biomass or concurrent grazing by yaks Bos grunniens and Tibetan sheep Ovis aries.3. In autumn there was significantly lower biomass outside fenced areas with year-round livestock grazing compared with inside fenced areas with equivalent or higher numbers of plateau pikas but predominantly winter grazing by livestock. Inside fenced areas, control of plateau pikas in spring produced no detectable effect on standing plant biomass at the end of the following summer compared with uncontrolled populations of plateau pikas.4. Regardless of their initial density, populations of plateau pikas declined rapidly over winter outside fenced areas where there was very low standing plant biomass in autumn. However, inside fenced areas with higher plant biomass in autumn, low-density populations of plateau pikas declined more slowly than high-density populations.5. Synthesis and applications. Current control programmes have limited effect because populations of plateau pikas can recover in one breeding season. There was no apparent increase in forage production in areas where plateau pikas were controlled. However, plateau pikas appear to benefit from changes in grazing management, with low-density populations declining less over winter inside fenced areas than elsewhere. It was not evident that control programmes are warranted or that they will improve the livelihoods of Tibetan herders.

Local warming about 1.3 degrees C in alpine meadow has no effect on root vole (Microtus oeconomus L.) population during winter

The influence of air and soil warming on root vole (Microtus oeconomus L.) population was studied in winter period in top open chambers (OTC) (0.8-1.8 m(2) warmed by conical fiberglass material and situated in alpine meadow (3250 m) at Qinghai-Tibet Plateau, China. The OTCs were distributed on an area of 30 x 30 m of experimental warming site; another site of the same area was a control one. The root vole population was investigated on two pairs of sites in "low-grazing" and "high-grazing" (by sheep) parts of the meadow; mark-recapture method was used. The winter-season averaged air and soil temperature inside of the chambers were 1.3 degrees C higher than the temperature outside the chambers. The warming in the chambers had no statistically significant effect on root vole numbers, on average body mass of individual, and on average body mass of males and females. In conclusion, as small as 1.3 degrees C warming of soil and air introduced locally and on small (several m(2)) scale, in the alpine meadow habitat in winter period, has possibly no effect on root vole numbers and biomass.

Tensor density matrix theory for determining population and alignment of symmetric top molecule using rotationally unresolved fluorescence

General expressions used for transforming raw laser-induced fluorescence (LIF) intensity into the population and alignment parameters of a symmetric top molecule are derived by employing the density matrix approach. The molecular population and alignment are described by molecular state multipoles. The results are presented for a general excitation-detection geometry and then applied to some special geometries. In general cases, the LIF intensity is a complex function of the initial molecular state multipoles, the dynamic factors and the excitation-detection geometrical factors. It contains a population and 14 alignment multipoles. How to extract all initial state multipoles from the rotationally unresolved emission LIF intensity is discussed in detail.

Time-dependent wavepacket approach to the influence of intense fields on the population of molecular excited states

The influence of laser-field parameters, such as intensity and pulse width, on the population of molecular excited state is investigated by using the time-dependent wavepacket method. For a two-state system in intense laser fields, the populations in the upper and lower states are given by the wavefunctions obtained by solving the Schrodinger equation through split-operator scheme. The calculation shows that both the laser intensity and the pulse width have a strong effect on the population in molecular excited state, and that as the common feature of light-matter interaction (LMI), the periodic changing of the population with the evolution time in each state can be interpreted by Rabi oscillation and area-theorem. The results illustrate that by controlling these two parameters, the needed population in excited state of interest can be obtained, which provides the foundation of light manipulation of molecular processes. (C) 2005 Elsevier B.V. All rights reserved.

C-Kit(+) Cells Isolated from Developing Kidneys Are a Novel Population of Stem Cells with Regenerative Potential

The presence of tissue specific precursor cells is an emerging concept in organ formation and tissue homeostasis. Several progenitors are described in the kidneys. However, their identity as a true stem cell remains elusive. Here, we identify a neonatal kidney-derived c-kit(+) cell population that fulfills all of the criteria as a stem cell. These cells were found in the thick ascending limb of Henle's loop and exhibited clonogenicity, self-renewal, and multipotentiality with differentiation capacity into mesoderm and ectoderm progeny. Additionally, c-kit(+) cells formed spheres in nonadherent conditions when plated at clonal density and expressed markers of stem cells, progenitors, and differentiated cells. Ex vivo expanded c-kit(+) cells integrated into several compartments of the kidney, including tubules, vessels, and glomeruli, and contributed to functional and morphological improvement of the kidney following acute ischemia-reperfusion injury in rats. Together, these findings document a novel neonatal rat kidney c-kit(+) stem cell population that can be isolated, expanded, cloned, differentiated, and used for kidney repair following acute kidney injury. These cells have important biological and therapeutic implications. STEM Cells 2013;31:1644-1656

Approximation-based feature selection and application for algae population estimation

Q. Shen and R. Jensen, 'Approximation-based feature selection and application for algae population estimation,' Applied Intelligence, vol. 28, no. 2, pp. 167-181, 2008. Sponsorship: EPSRC RONO: EP/E058388/1

Euro-Commentary : Scenario Analysis and Regional Economic Development: The Case of Mid Wales

Fuller-Love, Nerys, et al., 'Euro-Commentary : Scenario Analysis and Regional Economic Development: The Case of Mid Wales', European Urban and Regional Studies (2006) 13(2) pp.143-149 RAE2008

Problemy strefy Euro

Oficjalne kredyty ratunkowe dla niektórych krajów w strefie euro nie mogą zastąpić tam reform, które – poprawiając sytuację gospodarczą – pozwolą odzyskać owym krajom zaufanie rynków finansowych. W literaturze wymienia się dwie główne strukturalne słabości wspólnej waluty (euro): 1. Jednolita polityka pieniądza nie jest w stanie uwzględnić odmienności sytuacji poszczególnych krajów, a wspólny pieniądz nie pozwala na dewaluację w obrębie strefy euro; 2. Strefa euro istnieje bez „unii politycznej”. Artykuł analizuje zasadność tych tez.

A model for the simulation of macroalgal population dynamics and productivity

A mathematical model to simulate the population dynamics and productivity of macroalgae is described. The model calculates the biomass variation of a population divided into size-classes. Biomass variation in each class is estimated from the mass balance of carbon fixation, carbon release and demographic processes such as mortality and frond breakage. The transitions between the different classes are calculated in biomass and density units as a function of algal growth. Growth is computed from biomass variations using an allometric relationship between weight and length. Gross and net primary productivity is calculated from biomass production and losses over the period of simulation. The model allows the simulation of different harvesting strategies of commercially important species. The cutting size and harvesting period may be changed in order to optimise the calculated yields. The model was used with the agarophyte Gelidium sesquipedale (Clem.) Born. et Thur. This species was chosen because of its economic importance as a the main raw material for the agar industry. Net primary productivity calculated with it and from biomass variations over a yearly period, gave similar results. The results obtained suggest that biomass dynamics and productivity are more sensitive to the light extinction coefficient than to the initial biomass conditions for the model. Model results also suggest that biomass losses due to respiration and exudation are comparable to those resulting from mortality and frond breakage. During winter, a significant part of the simulated population has a negative net productivity. The importance of considering different parameters in the productivity light relationships in order to account for their seasonal variability is demonstrated with the model results. The model was implemented following an object oriented programming approach. The programming methodology allows a fast adaptation of the model to other species without major software development.

Retrieval by Shape Population: An Index Tree Approach

Based on our previous work in deformable shape model-based object detection, a new method is proposed that uses index trees for organizing shape features to support content-based retrieval applications. In the proposed strategy, different shape feature sets can be used in index trees constructed for object detection and shape similarity comparison respectively. There is a direct correspondence between the two shape feature sets. As a result, application-specific features can be obtained efficiently for shape-based retrieval after object detection. A novel approach is proposed that allows retrieval of images based on the population distribution of deformed shapes in each image. Experiments testing these new approaches have been conducted using an image database that contains blood cell micrographs. The precision vs. recall performance measure shows that our method is superior to previous methods.