Effects of Developmental Stage, Embryonic Interferon-τ Secretion and Recipient Synchrony on Pregnancy Rate after Transfer of in vitro Produced Bovine Blastocysts

Three separate trials of bovine embryo transfers were performed consisting of 32, 41 and 33 transfers, respectively, to examine the effects of (a) the developmental stage of in vitro‐derived blastocysts, (b) the amount of interferon‐τ (IFN‐τ) they secreted during culture and (c) the cyclic stage of the recipient at the time of transfer on the probability of establishment of pregnancy. One blastocyst was transferred into the ipsilateral uterine horn to the CL. At the time of transfer, blastocysts were classified into one of three developmental stages (early blastocyst, blastocyst and expanded blastocyst) and the cyclic stage of each cow was assessed (?12 h, on time, +12 h, +24 h, >24 h). Prior to the second and third trials, blastocysts were individually cultured for 24 h in 50 μl medium droplets and the IFN‐τ concentration in the droplet was determined. Logistic regression analyses revealed that expanded blastocysts had a significantly higher likelihood of establishing pregnancy (p = 0.009), and that there was a significant interaction with the cyclic stage of the recipient in this group with lower rates of pregnancy resulting from decreasing synchrony with the recipient (p = 0.033). IFN‐τ secretion during culture was significantly higher in expanded blastocysts than in the other two groups (p < 0.05). A significant effect of the pre‐transfer level of IFN‐τ secretion was found only in the ‘Blastocyst’ group where transfer of embryos with lower IFN‐τ production prior to transfer resulted in higher pregnancy rates (p = 0.047). These results demonstrate that IFN‐τ secretion may be a useful tool to predict pregnancy outcome, but only within certain developmental stages.     

转型中的亚洲林业(续一)

在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。     

Interband electronic excitation-assisted atomic-scale restructuring of metal surfaces by nanosecond pulsed laser light

Interaction of high-power laser light with materials often causes irreversible damage of the near-surface region. It is shown that copper single-crystal surfaces can be patterned by laser light. Irradiation with green light produced adatoms and vacancies, which self-organized into nanoscale pyramids. This restructuring can be removed by annealing. In contrast to green light, infrared laser irradiation at equivalent absorbed energy density did not produce any structural change. This, for metallic systems, unforeseen spectral difference in laser light action points to a concerted process as the source for structural modification, which involves long-lived primary excitation of localized d-electrons through interband transition together with phonon excitation.     

Expression of insulin-like growth factor genes in olive flounder,Paralichthys olivaceus,fed a diet with partial replacement of dietary fish meal

This study analyzed the expression of growth-related genes of olive flounder, Paralichthys olivaceus, fed a low-fish meal (FM) diet to investigate the replacement of the FM diet in the field. The expression of growth hormone (GH)/insulin-like growth factor (IGF) axis genes in the brain/pituitary/liver and plasma hormone concentrations were measured. A basal experimental diet was formulated using 63% FM and 12% soybean meal as the primary protein sources, and then two other diets were made by replacing 20% and 30% of the FM with soy protein concentrate, tankage meal, and poultry by-products meal. Each diet was fed to duplicate groups of juvenile flounder (150 ± 3.0 g) twice a day. After 20 weeks, the plasma growth-related hormone concentrations were similar between the control and FM20 groups. Moreover, GH/IGF axis gene mRNA expression in the brain/pituitary/liver was similar between the control and FM20 groups. Immunoblotting of muscle and liver showed the same pattern. This study showed the utility of replacing 20% of the FM diet and supports the possibility of field application.     

Three dimensional FEM simulation for spinning of non-circular fibers

A finite element method is employed for a flow analysis of the melt spinning process of a non-circular fiber, a PET(polyethylene terephthalate) filament. The flow field is divided into two regions of die channel and spin-line. A two dimensional analysis is used for the flow within the die channel and a three dimensional analysis for the flow along the spin-line. The Newtonian fluid is assumed for the PET melt and material properties are considered to be constant except for the viscosity. Effects of gravitation, air drag force, and surface tension are neglected. Although the spin-line length is 4.5 m, only five millimeters from the spinneret are evaluated as the domain of the analysis. Isothermal and non-isothermal cases are studied for the flow within the die channel. The relationship between the mass flow rate and the pressure gradient is presented for the two cases. Three dimensional flow along the spin-line is obtained by assuming isothermal conditions. It is shown that changes in velocity and cross-sectional shape occur mostly in the region of 1mm from the die exit.     

Synthesis of poly(norbornene ester)s by using (<Emphasis Type="Italic">η</Emphasis><Superscript>3</Superscript>-substituted allyl) palladium (NHC) complex as catalyst and investigation of their chemical structure - Glass transition temperature - Refractive index relationships

The synthesis of poly(norbornene ester)s by using a (η ³-substituted allyl) palladium (N-heterocyclic carbene (NHC)) complex as catalyst was performed and the relationship between chemical structure and glass transition temperature or refractive index of poly(norbornene ester)s was investigated. Norbornene ester monomers were synthesized via esterification of 5-norbornene-2-methyl alcohol and aromatic carboxylic acids. The polymerization catalyst, (η ³-substituted allyl) palladium (NHC) complex, was synthesized according to a published procedure. ¹H-NMR spectroscopy was performed to determine chemical structure of monomers and polymers. The molecular weight of the polymers was measured via gel permeation chromatography and the thermal properties were analyzed via thermogravimetric analysis and dynamic mechanical analysis. Refractive indices of polymer films were measured using a prism coupler. Polymers with the highest M _n (between 100 kg/mol and 300 kg/mol) were synthesized when the ratio of monomer to catalyst was 2000:1. The glass transition temperature of synthesized polymers was about 100 °C lower than that of conventional norbornene polymers. Among the six polymers of different chemical structures, four polymers exhibited a refractive index of 1.6 or more at a wavelength in the visible light region.     

Triazole fungicides and the selection of resistance to medical triazoles in the opportunistic mould Aspergillus fumigatus

Azole resistance is an emerging problem in the opportunistic mould Aspergillus fumigatus. The triazoles are the most important agents for the management of Aspergillus diseases in humans. Selection for acquired resistance may occur in the hospital setting through exposure to high doses of azoles during azole therapy, but evidence is accumulating that A. fumigatus may become resistant to medical triazoles through environmental exposure to fungicides. The recovery of A. fumigatus isolates resistant to the medical triazoles from azole‐naive patients as well as from the environment strongly indicates an environmental route of resistance selection. Molecule alignment studies have identified five fungicides that share a very similar molecule structure with the medical triazoles, and thus may have selected for mechanisms that confer resistance to both groups of compounds. It is important to explore further the presumed fungicide‐driven route of resistance selection in order to implement effective preventive measures as the prevalence of azole resistance in A. fumigatus continues to increase and causes major challenges in the management of azole‐resistant Aspergillus diseases. Copyright © 2012 Society of Chemical Industry     

Enhanced mechanical properties of silk fibroin-based composite plates for fractured bone healing

We successfully fabricated bacterial cellulose/silk fibroin (BC/SF) composite plates having similar strength to that of human cortical bone (12.8–17.7 GPa). The mechanical properties of the BC/SF composite plates were investigated at various BC nanofiber contents. The BC nanofibers acted as good reinforcements for the stress transfer produced by the interactions between the BC nanofibers and the SF matrix, as confirmed by the molecular deformation of the BC nanofibers. The BC/SF composite plates have a promising potential as a replacement material for existing metal bone plate.     

Enhanced dielectric properties of electrospun titanium dioxide/polyvinylidene fluoride nanofibrous composites

Titanium dioxide/polyvinylidene fluoride (TiO₂/PVDF) composite was prepared by electrospinning process to enhance the dielectric properties for application as a gate insulator in organic thin-film transistors (OTFTs). Scanning electron microscopy, thermogravimetric analysis, and X-ray diffraction were employed to characterize the as-prepared samples, and then their dielectric constants were investigated by impedance analysis. The impedance results show that the dielectric constant of the electrospun TiO₂/PVDF nanofibers is higher than those of other samples, demonstrating that electrospun TiO₂/PVDF composite can be a proper candidate for gate insulators in OTFTs.