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Abstract: Convergent lady beetles, Hippodamia convergens Guérin-Méneville are host to the braconid endoparasitoid, Dinocampus coccinellae (Schrank) and the microsporidian pathogen, Tubulinosema hippodamiae. The interrelationship between the endoparasitoid and the pathogen in H. convergens adults under laboratory conditions was examined by quantifying the effect of microsporidiosis on D. coccinellae development and host preference. Uninfected wasps were provided either uninfected or T. hippodamiae-infected beetles as hosts and the development of their progeny was observed over 30days. The duration of endoparasitoid development from egg deposition in the host until adult eclosion for D. coccinellae did not differ significantly, regardless of the infection status of the host beetle. All wasp progeny that developed within, and emerged from, T. hippodamiae-infected beetles were infected with the microsporidian pathogen (n= 48; 100% transmission). Infected D. coccinellae adults were also provided either uninfected or T. hippodamiae infected host beetles so that the development of their progeny could be assessed over 30days. Endoparasitoid development did not differ significantly; however, a significantly greater proportion of beetles stung by microsporidia-infected wasps did not contain an endoparasitoid larva when dissected at the end of the 30-day trial when compared to those stung by uninfected wasps. This suggests that the pathogen may reduce wasp fecundity or egg viability. Examination of paraffin-embedded D. coccinellae adult tissues revealed an extensive microsporidian infection throughout all major organs and tissues with exception of the ovary. During host choice trials, uninfected and microsporidia-infected D. coccinellae adults pursued, took an ovipositional stance, and attacked uninfected beetles more often than microsporidia-infected hosts but these observations did not differ significantly (P >0.05). [Copyright &y& Elsevier]

Abstract: The NF-κB signaling pathways have a critical role in the development and progression of various cancers. In this study, we demonstrated that the small cell lung cancer cell line (SCLC) H69 expressed a unique NF-κB profile as compared to other cancer cell lines. The p105/p50, p100/p52, c-Rel, and RelB protein and mRNA transcripts were absent in H69 cells but these cells expressed RelA/p65. The activation of H69 cells by lipopolysaccharide (LPS) resulted in the induction of RelB and p100 expression. The treatment also induced the nuclear translocation of RelB without the processing of p100 to p52. Furthermore, LPS-induced β1 integrin expression and cellular attachment through an NF-κB-dependent mechanism. Blocking RelB expression prevented the increase in the expression of β1 integrin and the attachment of H69. Taken together, the results suggest that RelB was responsible for the LPS-mediated attachment and may play an important role in the progression of some cancers. [Copyright &y& Elsevier]

Abstract: A microsporidium from Hippodamia convergens was transmitted horizontally to three non-target coccinellid hosts (Adalia bipunctata L., Coccinella septempunctata L. and Harmonia axyridis Pallas) under laboratory conditions. For all species examined, microsporidia-infected larvae took significantly longer to develop than did uninfected larvae but the microsporidium had no effect on larval mortality. Adult sex ratios of uninfected and microsporidia-infected adults were about 1:1 (♀:♂) and did not differ significantly. At the end of a 90-day trial, microsporidia-infected H. convergens produced significantly fewer eggs and did not live as long as uninfected individuals. Differences in fecundity and longevity were not observed for the three non-target coccinellids that were examined. Mean spore counts from smear preparations of microsporidia-infected A. bipunctata did not differ significantly from H. convergens, suggesting that A. bipunctata (a native coccinellid) is a suitable host for the microsporidium but infection was lighter in C. septempunctata and H. axyridis (introduced species). Vertical transmission of the pathogen was observed during the 90-day trial by examining eggs and larvae that were produced by microsporidia-infected adults. For all species examined, 100% vertical transmission of the pathogen was eventually observed. Three eugregarines were found in two adult A. bipunctata: Gregarine A trophozoites are similar in size to those of Gregarina katherina Watson (described earlier from Coccinella spp.), Gregarine B trophozoites are similar in size to those of Gregarine A but are morphology distinct, and Gregarine C trophozoites are similar in size to G. barbarara Watson (described earlier from A. bipunctata). [Copyright &y& Elsevier]

Abstract: Convergent lady beetles, Hippodamia convergens Guérin-Méneville, are a popular choice for aphid control in North America. An unidentified microsporidium was found in H. convergens adults that were purchased from a commercial insectary in 2004. This study examined egg cannibalism and egg predation as a means of horizontal transmission of the unidentified microsporidium among H. convergens larvae and three coccinellid species found in Nova Scotia: Coccinella septempunctata (seven-spotted lady beetle), C. trifasciata perplexa (three-banded lady beetle), and Harmonia axyridis (multicolored Asian lady beetle). The microsporidium was transmitted with 100% efficiency when first instars fed on microsporidia-infected eggs. Mean spore count data from smear preparations of infected beetles suggest that the infection was as heavy in C. trifasciata perplexa (a native coccinellid) (11.2±0.96 spores/100μm2) as it was in H. convergens (the natural host) (12.8±1.16) but lighter in the introduced species C. septempunctata (7.5±0.65) and H. axyridis (0.8±0.11). For all of the beetle species examined, larval development was significantly longer for microsporidia-infected individuals than for their uninfected cohorts. The microsporidium had no effect on larval mortality. Based on the results of this study, field-collected H. convergens should be examined for microsporidia and uninfected individuals should be used to rear individuals for release in biological control programs. However, this is unlikely to happen because H. convergens are relatively easy and inexpensive to collect from their overwintering sites for redistribution. [Copyright &y& Elsevier]

Abstract: The purpose of this study is to reveal the mechanism of unstable vibration occurring in the grinding operation of roller mills and to show the design guidelines for reducing the vibration. To study the basic cause of the unstable vibration, we first investigated the dynamic characteristics of the mill vibration in its stable state and its unstable state, using a small laboratory roller mill. This showed that the unstable vibration was due to the stick–slip motion of the rollers. Further, the modal analysis showed that the natural frequency of the torsional driving system of the mill corresponded with the unstable vibration frequency. Next, we researched the frictional and compressive characteristics of the ground materials using a simplified test apparatus. This showed that the ground material has a negative-damping property known to be the cause of the self-excited vibration. Furthermore, we proposed the analytical vibration model for the simplified test apparatus considering the negative-damping property, as well as the corresponding equations of motion. By integrating them numerically, fluctuating phenomena similar to the experimental results were obtained. [Copyright &y& Elsevier]

This paper presents the development of a numerical code for simulating unsteady dusty-gas flows including shock and rarefaction waves. The numerical results obtained for a shock tube problem are used for validating the accuracy and performance of the code. The code is then extended for simulating two-dimensional problems. Since the interactions between the gas and particle phases are calculated with the operator splitting technique, we can choose numerical schemes independently for the different phases. A semi-analytical method is developed for the dust phase, while the TVD scheme of Harten and Yee is chosen for the gas phase. Throughout this study, computations are carried out on SGI Origin2000, a parallel computer with multiple of RISC based processors. The efficient use of the parallel computer system is an important issue and the code implementation on Origin2000 is also described. Flow profiles of both the gas and solid particles behind the steady shock wave are calculated by integrating the steady conservation equations. The good agreement between the pseudo-stationary solutions and those from the current numerical code validates the numerical approach and the actual coding. The pseudo-stationary shock profiles can also be used as initial conditions of unsteady multidimensional simulations. [Copyright &y& Elsevier]

Abstract: Hippodamia convergens, the convergent lady beetle, is available for aphid control in home gardens and in commercial food production systems throughout the United States and Canada. Beetles received from commercial insectaries for biological control are occasionally infected with a microsporidium. The objective of this study was to describe the pathogen by means of ultrastructure, molecular characterization and tissue pathology. All stages of the microsporidium were in direct contact with the host cell cytoplasm. Early developmental stages were proximal to mature spores and both were observed throughout the tissue sections that were examined. Merogony resulted from binary fission. Early-stage sporoblasts were surrounded by a highly convoluted plasma membrane and contained an electron-dense cytoplasm and diplokaryon. Ovoid to elongated late-stage sporoblasts were surrounded by a relatively complete spore wall. The polar filament, polaroplast, and anchoring disk were readily observed within the cell cytoplasm. Mature spores were typical of terrestrial microsporidia, with a thickened endospore surrounded by a thin exospore. Spores contained well-defined internal structures, including a diplokaryon, lamellar polaroplast and a slightly anisofilar polar filament with 10–14 coils arranged in a single or double row. A prominent indentation was evident at the apical end of the spore wall proximal to the anchoring disk. Aberrant spores were also observed. These had a fully developed endospore and exospore but lacked any discernable internal spore structures, and were, instead, filled with lamellar or vesicular structures. Typical and aberrant spores measured 3.58±0.2×2.06±0.2μm (n =10) and 3.38±0.8×2.13±0.2μm (n =10), respectively. Spores were observed in longitudinal muscle surrounding the midgut and within the fat body, Malpighian tubules, pyloric valve epithelium, ventral nerve cord ganglia, muscles and ovaries. The hindgut epithelium was often infected but the connective tissues were rarely invaded. The life cycle and pathology of the microsporidium bears some resemblance to Nosema hippodamiae, the only microsporidium reported from H. convergens by Lipa and Steinhaus in 1959. Molecular characterization of the pathogen genomic DNA revealed that it is 99% similar to Tubulinosema acridophagus and T. ratisbonensis, two pathogens that infect Drosophila melanogaster and 98% similar to T. kingi from D. willistoni. Based on similarities in pathogen ultrastructure and the molecular information gained during this study, we propose that the microsporidium in H. convergens be given the name Tubulinosema hippodamiae. [Copyright &y& Elsevier]

• The reliable VLE data for R1123/R1234yf binary mixtures were measured. • The recirculation type apparatus was used by two different technicians. • Systematic deviation from the available Helmholtz-type model was observed. • The modified Peng-Robinson equation of state were regressed with the present data. The vapour–liquid equilibrium properties of binary mixtures of R1123 and R1234yf, which are key components of the next generation of refrigerant mixtures, were measured using a recirculation-type vapour–liquid equilibrium property measurement apparatus. Two sets of measurements were conducted by two different technicians (co-authors Nishida and Saito) using the same apparatus and sample. The first set of measurements were conducted at temperatures that were close to the integer values in absolute temperature, whereas the second set of measurements was taken at temperatures that were close to the integer values in terms of degrees Celsius. Both sets of measurements were based on the ITS-90 temperature scale and were found to be in good agreement at the measurement temperatures (300 and 330 K). These data were compared with the predictions of a Helmholtz-type equation of state, and a systematic deviation of approximately 8% was observed at low temperatures. A regression analysis using the binary interaction parameter k ij of the modified Peng–Robinson equation of state more accurately reproduced the experimental measurements. [ABSTRACT FROM AUTHOR]

This study examined isotope fractionation during bronze casting and assessed variation in Sn isotope composition of Chinese bronze products to ascertain whether a Sn isotope tracer is applicable to provenance studies of bronze products or not. A casting experiment revealed that the Sn isotope composition of a bronze block surface becomes slightly heavier, 0.22‰ in δ 124 Sn/ 120 Sn scale, (δ 124 Sn/ 120 Sn = [( 124 Sn/ 120 Sn sample )/( 124 Sn/ 120 Sn standard )−1] × 10 3 ), than original Sn beads because of selective evaporation of light isotopes. The Sn isotope compositions of six bronze product samples excavated in China were analyzed. The variation of δ 124 Sn/ 120 Sn in the six samples was as great as 0.4‰. Six bronze samples showed small but detectable isotope variation that surpassed isotope shift during casting. Results suggested that the application of Sn isotope ratio to provenance studies of bronze products was of limited use because of the small variation. However, it was also shown that the Sn isotope ratio can be applied for provenancing a bronze sample with a distinct isotope composition. [ABSTRACT FROM AUTHOR]

Highlights: [•] A microsporidium was found in Chrysoperla carnea from a commercial insectary. [•] Infection of C. carnea adults was systemic but the hindgut was heavily infected. [•] Microsporidian spores were not observed within developing C. carnea eggs. [•] Diplokaryotic spores (3.49×1.52μm) had isofilar polar filaments with 8–10 coils. [•] The genome sequence of the microsporidium was 99% similar to four Nosema species. [ABSTRACT FROM AUTHOR]

Sturgeon spermatozoa are immotile in the testis and acquire the potential for motility after contact with urine in Wolffian duct. The present study tested if in vitro incubation of testicular sperm in seminal fluid from Wolffian duct sperm leads to the acquisition of sperm fertilization ability. Sterlet sperm was taken from the testes, matured in vitro and cryopreserved. The fertility and motility of cryopreserved semen were tested. Matured testicular sperm showed freeze–thaw survival rates similar to Wolffian duct sperm, which is commonly used in sturgeon artificial propagation. Matured testicular sperm and Wolffian duct sperm post-thaw motility rate and curvilinear velocity were not significantly different, while duration of matured testicular sperm motility was significantly shorter than that of Wolffian duct sperm. Development rates of embryos obtained with post-thaw matured testicular sperm and Wolffian duct sperm were not significantly different. In vitro maturation of sterlet testicular sperm can potentially be useful in sperm cryobanking. [ABSTRACT FROM AUTHOR]