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It would not surprise that two related termite species are similar in many traits, especially those related to reproduction such as similarity in sexual organs, spermathecae, gametes, glands in genital organs and micropyles of eggs. Because similarities of them are thought to be directly linked to increase their reproductive fitness. Moreover, the key data showing successful hybridization between the two termite species under laboratory conditions and in the field. The present study was conducted on the base of morphometric analyses and histological examinations of the sperm, testes, vas deferens, accessory glands, ejaculatory duct and spermathecae of Reticulitermes flaviceps and R. chinensis. The accessory glands of male alates were found without spermatozoa in both termites. The patterns of spermatogenesis in the alate testes of both species were quite similar and the gametes (spermatogonia, spermatocytes, spermatids, and sperm) produced in a sequence of essential developmental processes. The aflagellated sperm were transferred by male numerous times in a day after few copulations. They were stored alive in spermatheca by female and used for fertilization of oocytes. The nutrition was obtained by the sperm from the secretory cells, for a living and being functional during storage in the spermathecae. The spermathecae have finger shape and their thick walls divided into 4 type cells. Anatomically spermathecae of the two termite species consisted of lumens, ductules, and few glands, in thick wall structures. While the entire examinations revealed no more differences in the sexual organs of the two different species since R. flaviceps and R. chinensis can hybridize under experimental conditions as well as in wild to produce offspring. The similarity in the structure of sexual organs of both heterospecies provides possible evidence for the successful hybridization. [ABSTRACT FROM AUTHOR]

The subterranean termite Reticulitermes aculabialis was firstly described from the soldier caste in 1977 and diagnose from the imago has been difficult due to the lack of description of alate. In this paper, a detailed description of alate for R. aculabialis is presented, including additional data to soldiers. The data are chiefly based on the external morphology of R. aculabialis imago, which has never been described before. All the samples of alates and soldiers were collected in Xi'an, Shaanxi province, China. All of the essential specific characteristics are illustrated for identification purposes. [ABSTRACT FROM AUTHOR]

Insulin is a protein hormone that controls the metabolism of sugar, fat and protein via signal transduction in cells, influencing growth and developmental processes such as reproduction and ageing. From nematodes to fruit flies, rodents and other animals, glucose signalling mechanisms are highly conserved. Reproductive termites (queens and kings) exhibit an extraordinarily long lifespan relative to non-reproductive individuals such as workers, despite being generated from the same genome, thus providing a unique model for the investigation of longevity. The key reason for this molecular mechanism, however, remains unclear. To clarify the molecular mechanism underlying this phenomenon, we sequenced the transcriptomes of the primary kings (PKs), primary queens (PQs), male (WMs) and female (WFs) workers of the lower subterranean termite Reticulitermes chinensis. We performed RNA sequencing and identified 33 insulin signalling pathway-related genes in R. chinensis. RT-qPCR analyses revealed that EIF4E and RPS6 genes were highly expressed in WMs and WFs workers, while mTOR expression was lower in PKs and PQs than in WMs and WFs. PQs and PKs exhibited lower expression of akt2-a than female workers. As the highly conserved insulin signalling pathway can significantly prolong the healthspan and lifespan, so we infer that the insulin signalling pathway regulates ageing in the subterranean termite R. chinensis. Further studies are recommended to reveal the biological function of insulin signalling pathway-related genes in the survival of termites to provide new insights into biomolecular homeostasis maintenance and its relationship to remarkable longevity. [ABSTRACT FROM AUTHOR]

As spectra-based fault localization techniques report suspicious statements by analyzing the coverage of test cases, the effectiveness of the results is highly dependent on the composition of test suites. This paper proposes an approach for selecting a subset of the passed test suite when a failure revealed by a failed test case. The goal is to obtain a more effective fault localization using a minimal number of test cases than using the originally given large number of test cases. A novelty is that a prioritization criterion and a selection criterion are defined. Different from previous studies, the failed trace is fully considered. The prioritization criterion partitions statements in the failed trace into more suspicious and less suspicious, and then ranks passed test cases by their ability in distinguishing the more suspicious statements from the less suspicious ones. The selection criterion selects the minimal passed test suite which can maximize the number of coverage equivalent classes in the failed trace, so as to distinguish the suspicious statements and meanwhile reduce the size of the test suite. Another novelty is that our approach turns the test case selection into a multi-criteria optimization to make the prioritization and the selection criteria complement each other. This approach was evaluated with 5 fault localization techniques, 8 subject programs and 35,392 test cases. The results show that the fault localization effectiveness can be significantly improved with less than 5% passed test cases. Our approach has advantages over the statement- based and vector-based test suite reduction approaches in both fault localization effectiveness and test suite reduction rate. [ABSTRACT FROM AUTHOR]

We report the complete mitochondrial genome (mtDNA) of the subterranean termite Reticulitermes flaviceps. The mtDNA is 16,485 bp long in size. The 13 protein-coding genes have typical ATN initiation codon. But the stop codons were TAA, TAG and an incomplete termination codon (T) abutting an adjacent tRNA gene. Twenty-two tRNA genes, in addition to tRNA (AGN) replaced lacking of the DHU stem with a simple loop, showed the typical clover-leaf secondary structure. The A + T-rich region was 1677 bp in length with 70.3 % A + T content. Addition to the A + T-rich region, non-coding sequences of the mtDNA genome harbored 18 intergenic spacers. There were two complete repeats and one partial repeats of repeat A and repeat B in CR. Phylogenetic tree based on the 12 complete mitochondrial genome sequences of closely related termite species accords well with the morphological phylogenetic analysis. [ABSTRACT FROM AUTHOR]

An unsteady magnetohydrodynamic (MHD) boundary layer flow over a shrinking permeable sheet embedded in a moving viscous electrically conducting fluid is investigated both analytically and numerically. The velocity slip at the solid surface is taken into account in the boundary conditions. A novel analytical method named DTMBF is proposed and used to get the approximate analytical solutions to the nonlinear governing equation along with the boundary conditions at infinity. All analytical results are compared with those obtained by a numerical method. The comparison shows good agreement, which validates the accuracy of the DTM-BF method. Moreover, the existence ranges of the dual solutions and the unique solution for various parameters are obtained. The effects of the velocity slip parameter, the unsteadiness parameter, the magnetic parameter, the suction/injection parameter, and the velocity ratio parameter on the skin friction, the unique velocity, and the dual velocity profiles are explored, respectively. [ABSTRACT FROM AUTHOR]

Furfural from lignocellulosic hydrolysates is the prevalent inhibitor to microorganisms during cellulosic ethanol production, but the molecular mechanisms of tolerance to this inhibitor in Zymomonas mobilis are still unclear. In this study, genome-wide transcriptional responses to furfural were investigated in Z. mobilis using microarray analysis. We found that 433 genes were differentially expressed in response to furfural. Furfural up- or down-regulated genes related to cell wall/membrane biogenesis, metabolism, and transcription. However, furfural has a subtle negative effect on Entner-Doudoroff pathway mRNAs. Our results revealed that furfural had effects on multiple aspects of cellular metabolism at the transcriptional level and that membrane might play important roles in response to furfural. This research has provided insights into the molecular response to furfural in Z. mobilis, and it will be helpful to construct more furfural-resistant strains for cellulosic ethanol production. [ABSTRACT FROM AUTHOR]

The magnetohydrodynamic (MHD) Falkner-Skan boundary layer flow over a permeable wall in the presence of a transverse magnetic field is examined. The approximate solutions and skin friction coefficients of the MHD boundary layer flow are obtained by using a method that couples the differential transform method (DTM) with the Padé approximation called DTM-Padé. The approximate solutions are expressed in the form of a power series that can be easily computed with an iterative procedure. The approximate solutions are tabulated, plotted for the values of different parameters and compared with the numerical ones obtained by employing the shooting technique. It is found that the approximate solution agrees very well with the numerical solution, showing the reliability and validity of the present work. Moreover, the effects of various physical parameters on the boundary layer flow are presented graphically and discussed. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]