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51.
Albart Coster John WM Bastiaansen Mario PL Calus Johan AM van Arendonk Henk Bovenhuis 《遗传、选种与进化》2010,42(1):9
The objective of this simulation study was to compare the effect of the number of QTL and distribution of QTL variance on the accuracy of breeding values estimated with genomewide markers (MEBV). Three distinct methods were used to calculate MEBV: a Bayesian Method (BM), Least Angle Regression (LARS) and Partial Least Square Regression (PLSR). The accuracy of MEBV calculated with BM and LARS decreased when the number of simulated QTL increased. The accuracy decreased more when QTL had different variance values than when all QTL had an equal variance. The accuracy of MEBV calculated with PLSR was affected neither by the number of QTL nor by the distribution of QTL variance. Additional simulations and analyses showed that these conclusions were not affected by the number of individuals in the training population, by the number of markers and by the heritability of the trait. Results of this study show that the effect of the number of QTL and distribution of QTL variance on the accuracy of MEBV depends on the method that is used to calculate MEBV. 相似文献
52.
The foraging activity of Constrictotermes cyphergaster was investigated in the Caatinga of Northeast Brazil. Eight colonies were monitored for seven days, during both dry and wet
seasons. Foraging activity occurred in exposed columns at night, generally between 22:00 and 05:00 h. During the wet season,
foraging activity was significantly higher, with one bout every 1.6 ± 0.2 days, than the dry season, when foraging bouts
were performed every 1.9 ± 0.3 days. Foraging activity throughout the study colonies presented high temporal synchronization.
In both seasons, foraging was negatively correlated with air temperature and positively correlated with humidity. The foraging
trails were often re-utilized and ranged from 1 to 18.5 meters in length. No difference between seasons in the area potentially
utilized by the study colonies was observed. Approximately 51000 individuals participated in the foraging bout during the
dry season, whereas some 87000 individuals participated in the foraging bout during the wet season. This corresponds to 43
and 74% of the estimated total nest population for the dry and wet seasons respectively. The average ratio soldiers:workers
during foraging was 1:1.2 in the dry season and 1:2 in the wet season. The higher frequency and number of individuals foraging
during the wet season in the present study are likely to be a strategy from C. cyphergaster to store energy reserves to be utilized during the dry season.
Received 28 November 2005; revised 29 May 2006 and 16 August 2006; accepted 1 September 2006. 相似文献
53.
Following Fr?hlich we consider a system that models a biological one, for example, a long chain of proteins possessing polar modes of vibration and where energy is pumped through metabolic processes. We consider the effect produced by free electrons that are usually present as hole carriers in proteins with electron-donor molecules. A theory of relaxation based on the non-equilibrium statistical operator method is used in the derivation of the kinetic equations to introduce non-linearities due to interactions of the polar vibrations with the carriers and with a thermal bath. These non-linearities arising from high order relaxation processes lead to the emergence of the Fr?hlich effect in the polar modes, i.e. the occurrence of a (non-equilibrium) Bose-Einstein-like condensation. It points to an instability of the system that seems to be followed by a morphological transformation in the form of a spatially ordered dissipative structure. 相似文献
54.
55.
Emilio Lanna Bruno Cajado Danyele Santos Fabiana Cruz Franciele Oliveira Vivian Vasconcellos 《Invertebrate reproduction & development.》2018,62(3):133-142
To comprehend the state of the art of sponge reproduction science (SRS), we quantified and analyzed the trends in SRS in the last decade, aiming to answer three questions: (i) Were there fewer SRS works presented during the last sponge conference? (ii) Did the number of SRS publications decline in the last decade? (iii) Does the number of abstracts at sponge conferences influence overall SRS publications? In addition, we checked whether the SRS community has answered Ereskovsky’s ‘five important questions’, enabling us to advance SRS enough to be considered as a fourth period of this scientific field. We found that SRS was less represented at the last sponge conference, despite an increase in the number of publications during the last decade. Moreover, the number of abstracts presented at sponge conferences contributed to a small portion (25%) of the published works in this area during the last decade. In addition, we found that two of the five Ereskovsky’s questions are still mostly not answered. Thus, we conclude that SRS is healthy and advancing steadily, especially in some subareas (e.g. developmental biology and life history). There are still much to advance, but this is still a strong field of biological science research. 相似文献
56.
Jifeng Tang Samantha J Baldwin Jeanne ME Jacobs C Gerard van der Linden Roeland E Voorrips Jack AM Leunissen Herman van Eck Ben Vosman 《BMC bioinformatics》2008,9(1):374
Background
Simple Sequence Repeat (SSR) or microsatellite markers are valuable for genetic research. Experimental methods to develop SSR markers are laborious, time consuming and expensive. In silico approaches have become a practicable and relatively inexpensive alternative during the last decade, although testing putative SSR markers still is time consuming and expensive. In many species only a relatively small percentage of SSR markers turn out to be polymorphic. This is particularly true for markers derived from expressed sequence tags (ESTs). In EST databases a large redundancy of sequences is present, which may contain information on length-polymorphisms in the SSR they contain, and whether they have been derived from heterozygotes or from different genotypes. Up to now, although a number of programs have been developed to identify SSRs in EST sequences, no software can detect putatively polymorphic SSRs. 相似文献57.
Eneas Carvalho Angela S. Barbosa Aurora M. Cianciarullo Patrícia A. Abreu Maria L.S. Oliveira Amane P. Gonçales Sílvio A. Vasconcellos 《FEBS letters》2009,583(8):1381-1385
The role of TlyA, TlyB and TlyC proteins in the biology of Leptospira is still uncertain. Although these proteins have been considered as putative hemolysins, we demonstrate that leptospiral recombinant TlyB and TlyC do not possess hemolytic activity. However, further experiments showed that TlyC is a surface-exposed protein that seems to bind to laminin, collagen IV and fibronectin. The expression of both proteins was detected both in vitro and in vivo. Our findings suggest that TlyB and TlyC are not directly involved in hemolysis, and that TlyC may contribute to Leptospira binding to extracellular matrix (ECM) during host infection. 相似文献
58.
59.
Seppo AM Saari Kirsi H Juuti Joanna H Palojärvi Kirsi M Väisänen Riitta-Liisa Rajaniemi Leena E Saijonmaa-Koulumies 《Acta veterinaria Scandinavica》2009,51(1):40
Background
Demodex gatoi is unique among demodectic mites. It possesses a distinct stubby appearance, and, instead of residing in the hair follicles, it dwells in the keratin layer of the epidermis, causing a pruritic and contagious skin disease in cats. Little is known of the occurrence of D. gatoi in Europe or control of D. gatoi infestation. 相似文献60.
Simões PS Perosa SR Arganãraz GA Yacubian EM Carrete H Centeno RS Varella PP Santiago JF Canzian M Silva JA Mortara RA Amado D Cavalheiro EA Mazzacoratti Mda G 《Neurochemistry international》2011,58(4):477-482
Kallikrein 1 (hK1) is a tissue enzyme responsible for kinin release in inflammatory cascade. This study was delineated to study the distribution and the co-localization of hK1 and kinin B1 and B2 receptors with glial and/or neuronal proteins markers, in the hippocampus of patients with refractory temporal lobe epilepsy, associated with hippocampal sclerosis (TLE-HS), comparing with control tissues. Hippocampal levels of KLK1 mRNA were also measured. hK1, kinin B1 and B2 receptors, NeuN and GFAP were analyzed using immunohistochemistry and confocal microscopy and KLK1 mRNA was quantified with real time PCR. Increased expression of hK1 by astrocytes co-localized with GFAP was found, contrasting with kinin B1 and B2 receptors, which were co-localized with NeuN in the sclerotic hippocampus. In addition, KLK1 mRNA was also up-regulated in same tissues. These data suggest an overexpression of kallikrein-kinin system and a neuron-glia interaction in the inflammatory process present in refractory TLE-HS. 相似文献