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AbstractDengue hemorrhagic fever (DHF) is severe dengue with a hallmark of vascular leakage. β-tryptase has been found to promote vascular leakage in DHF patients, which could be a potential target for DHF treatment. This study aims to develop a theoretical background for designing and selecting human β-tryptase inhibitors through computational studies. Thirty-four α-keto-[1,2,3]-oxadiazoles scaffold-based compounds were used to generate 2D-QSAR models and for molecular docking studies with β-tryptase (PDB Code 4A6L). In addition, molecular dynamics (MD) simulation and molecular mechanics generalised born surface area (MM-GBSA) analysis on the binding of the reported most active compound, compound 11e, towards β-tryptase were performed. Finally, a structure-based pharmacophore model was generated. The selected 2D-QSAR models have statistically proven good models by internal and external validation as well as the y-randomization test. The docking results of compound 11e showed lower CDOCKER energy than the 4A6L co-crystallised ligand and a similar binding pattern as the 4A6L co-crystallised ligand. From molecular dynamics simulation, 4A6L in compound 11e bound state has RMSD below 2 Å throughout the 500 ns simulation, indicating the docked complex is stable. Besides, MM-GBSA analysis suggested the 4A6L-compound 11e docked complex (−66.04 Kcal/mol) is structurally as stable as the 4A6L-native ligand co-crystallized structure (−66.84 Kcal/mol). The best pharmacophore model identified features included hydrogen bond acceptor, ionic interaction, hydrophobic interaction, and aromatic ring, which contribute to the inhibitory potency of a compound. This study supplied insight and knowledge for developing novel chemical compounds with improved inhibition of β-tryptase.Communicated by Ramaswamy H. Sarma

The deep high-temperature, high-pressure Lower Cretaceous Bashijiqike sandstone (buried to depths as great as 6.5-7.1 km [21,325-23,293 ft]) is an important natural gas reservoir in Keshen gas field, Kuqa depression of the Tarim basin. Reservoir quality is a critical risk factor in the development of these ultradeep reservoirs. Integrated approaches incorporating routine core analyses and mineralogical, petrographic, and geochemical analyses have been used to investigate the diagenetic history of these rocks and their effect on reservoir quality with the aim to unravel the mechanisms for maintaining anomalously high porosities in sandstones that are buried to such a great depth. These sandstones are dominantly fine- to medium-grained, moderately to well-sorted lithic arkoses and feldspathic litharenite. Most primary pores have been lost by mechanical compaction or carbonate cementation, and the reduction of porosity by mechanical compaction was more significant than that by cementation. Dissolution of framework grains contributed to the enhancement of reservoir quality. Eogenetic diagenetic alterations mainly include mechanical compaction, precipitation of calcite cements, and grain-coating clays, and mesogenetic diagenesis is characterized by dissolution of framework grain by organic acids and subsequent precipitation of clay minerals and quartz. Infiltration of meteoric water related to teleodiagenesis would result in dissolution of the framework grains. The meteoric leaching events during teleodiagenesis are of great importance for the Bashijiqike sandstones. Grain-coating clay minerals (mixed-layer illite/smectite clays) help to preserve porosity at depth by retarding quartz cementation and pressure solution. The unique burial regime as early-stage shallow burial with late-stage rapid deep burial contributes to porosity preservation in eodiagenesis. Fluid overpressure caused by intense structural compression in the middle Himalayan movement retarded compaction and helped preserve porosity in the late rapid deep burial stage. Anomalously high porosities are mainly found in mediumgrained, well-sorted sandstones with grain-coating clays but with low clay and carbonate cement content, of which the porosity is preserved primarily and enhanced secondarily. The lowest porosities are associated with sandstones that are tightly compacted or cemented with carbonates or rich in detrital matrix. Porosity-depth trends may vary significantly with lithofacies because of their differences in textural and compositional attributes. Five lithofacies are defined in terms of detrital composition and texture and type and degree of diagenesis. The reservoir quality prediction models of various lithofacies are constructed, and the results of this study provide insights into mechanisms for maintaining anomalously high porosity and permeability in high-temperature, high-pressure sandstone reservoirs and may help explain hydrocarbon distribution. [ABSTRACT FROM AUTHOR]

In this paper the frictional and tensile properties of stainless-steel fiber, cotton fiber, polyester fiber and rayon fiber, as well as the tensile and surface hairy properties of stainless-steel yarn, cotton yarn and wool yarn were tested and compared. Experimental results shown that the stainless-steel fiber has greater density, friction coefficient and tensile breakage strength but smaller breaking elongation. On the basis of summarizing the differences between stainless-steel fiber (yarn) and conventional textile fibers (yarns), difficulties occurred during knitting process were analyzed and the corresponding solutions were proposed.

AbstractUsing immunostaining methodology, we traced the axonal projection of FMRFamide (Phe-Met-Arg-Phe-NH2)-like immunoreactive (LI) medial neurosecretory cells (MNCs) and lateral neurosecretory cells (LNCs) from the brain into the ventral nerve cord (VNC) and retrocerebral complex in Bombyx mori(L.) (Lepidoptera: Bombycidae). Of the seven pairs of FMRFamide-LI MNCs, one pair extended its axons from the brain pars intercerebralis into the VNC ipsilateral connective where they appeared to terminate. The axons of the remaining MNCs ran through decussation in the brain median region and contralateral nervi corporis cardiaci (NCC) I out of the brain, and eventually innervated the contralateral corpus cardiacum (CC). Axons from the single pair of FMRFamide-LI LNCs projected into the ipsilateral NCC II fused with NCC I without decussation in the brain, and finally terminated in the CC. These results suggest that transport of the FMRFamide-like neuropeptide from may be related to the modulation of functions such as gut contraction in MNCs terminating in the VNC, and regulation of production and/or secretion of specific hormones such as juvenile hormone in MNCs and LNCs terminating in the CC.

The desired phase-transition temperature and enthalpy of phase change materials are different in different application fields. When the composite way is reasonable, the phase-transition temperature and enthalpy of phase change can satisfy the demand of PCMs using in clothes. Based on The theory of eutectic system and the Schroeder Formula, the lowest eutectic point was computed by using MATLAB software in this paper, and then the enthalpy of phase change was also compared in order to get the best proportion of PCMs.

Stainless steel fiber is a new sort of soft industrial material developed in the past decades. The pure stainless fiber has a number of outstanding properties and is getting wider range of application in textiles which are used as industrial textiles. The tensile properties between stainless steel fiber and traditional textile fibers are quiet different. The property differences between stainless fiber and common textile fiber made the textile processing of stainless fiber difficult. Based on the testing of breaking force, breaking strength and breaking elongation rate, this paper analyzed the tensile characteristic of stainless fiber and discussed its effect on yarn quality.

Stainless fabrics are getting wider range of application because of its excellent properties such as high temperature resistance, resistance to corrosion, high efficient filter etc.. The property differences between stainless yarn and common textile yarn made the knitting processing of stainless yarn difficult. Based on the analyzing of the main mechanical performance characteristic of stainless yarn, this paper analyzes the effective measures should be taken for the smooth going of the knitting process.

Pure stainless fiber products have many excellent properties such as high temperature resistance, resistance to corrosion, high efficient filter etc.. Pure stainless fabrics are getting wider range of application in the field of industrial textiles. The property differences between stainless fiber and common textile fiber made the textile processing of stainless yarn difficult. Based on the testing of dynamic friction coefficient, static friction coefficient, breaking strength and breaking elongation, this paper analyzes the main performance characteristic of stainless fiber and the reasons that makes textile processing difficult. Countermeasures for fabric manufacturing are suggested accordingly.

Based on fundamental principles of Fourier's law of heat conduction, Newton's law of cooling, Stefan-Boltzmann law and the law of conservation of energy, this paper gave out mathematical equations for description of the general heat transfer process through clothing system, and compares the theoretical results with experimental results. The result of the experiment is in accordance with the theoretical prediction.

The research reported here examines heat buffering property changes of phase change materials used in textiles. In the study, six types of fabrics with different warmth retention rate catalogued in two groups were used to determine how warmth retention rate of fabric affect heat buffering time of PCM when fabric was wrapped around PCM pouches. It was found that the greater the warmth retention rate of the wrapped fabric, the longer the heat buffering time of the PCM pouch, we also found that the heat buffering time prolonged in direct proportion to the warmth retention rate in different manners for fabrics weaved by fibers that have different heat conductivity. Greater warmth retention rate and smaller fiber conductivity lead to greater increase of the heat buffering time of PCM pouches. The results in this research suggested a possibility about how to control heat buffering time of PCM-containing textiles.

Three‐dimensional reconstructions of a hematopoietic organ (HPO) from Bombyx mori larva were undertaken using light and electron microscopy. Each compact islet varied in sizes, but in the central area of the HPO their size became smaller. Compact islets and loose islets were made up of prohemocytes, plasmatocytes, and reticular cells, but there were differences in the proportions of these cells. Within the cytoplasm of reticular cells and within their cell projection, vacuoles were observed. Cell proliferation occurs primarily in the compact islets, and differentiation associated with the reticular cells occurs primarily in the loose islets. It can be inferred that reticular cells have a significant influence on proliferation and differentiation associated with hematopoiesis. According to the results of the 3‐D reconstruction, one reticular cell is in contact with eight or nine hemocytes. Each reticular cell is presumably of approximately ten hemocytes. Movies relevant to Figs. 3, 4 and 5 can be found at http://biotech.korea.ac.kr/ cellbio/pages/ 3D‐results.html.

Ultrastructure of epithelial cells constituting the Malpighian tubule of Anopheles sinesislast instar larvae was observed with electron microscope. Malpighian tubule consists of four long and narrow tubule structures with principal cells in typical absorptive cells and regenerative cells forming the simple epithelium. Apical plasma membrane of the principal cell is differentiated into microvilli with one mitochondrion in each microvilli. Basal plasma membrane had extreme infolding to form a canaliculi and a well developed mitochondria was attached in the infoldings. And, rER, ribosomes, and vacuoles were well developed inside the cells. However, there were two main cell types depending on the differentiation of cell organelles. Type 1 cell was cubic, forming the distal portion of Malpighian tubule. The length of microvilli was approximately 4 μm and the basal infoldings were introjected to the depth of 2 μm inside the cell. On the other hand, Type II cell that formed the main proxinal portion was a low squamous type cells with shorter 2 μm of microvilli and the basal infoldings were introjected to the depths of 4 μm inside the cell. As for vacuoles scattered inside the cells, they were regularly observed in both Type I and II and the Type II cells had better developed cellular organelles. Although regenerative cells were extremely small, their cellular organelles were developed and their overall electron density was high that they appeared darker than the principal cells.

ABSTRACT This study has been carried out to investigate localization of allatostatin‐producing cells in the gut of Agrius convolvuliusing an immunocytochemical method. Allatostatin producing cells could not be found in the foregut and hindgut, but they were abundantly distributed only in the posterior part of midgut. These endocrine cells had typically columnar shape, with secretory surface positioned to muscular layer of midgut wall and also showed different intensity of immunoreactivity to AST, mainly with strong or moderate intensity.

ABSTRACT The Ultrastructure of rectum epithelial cells in the mosquito larvae, Anopheles sinensisWiedemann, was studied using electron microscope. The rectal epithelium forms rectal papillae composed of the absorptive cells and the surrounding basal cells. Moreover, rectal epithelium was covered with thin cuticular intima. Apical plasma membrane of the epithelial cells had infoldings and in between them, mitochondria developed into elongated shape were attached. In addition, the membrane infoldings reach down into the cell cytoplasm to form several layers of leaflet‐like prolongations. On both sides of these prolongations were also large, well‐developed mitochondria. Their formation was that mitochondria were attached to 3 μm length and 4–13 layers of membrane wrinkle lump. Many spherites, which are lamelated crystals that form an illusory structure in concentric circles inside of the cytoplasm of epithelial cell were observed. Basal plasma membrane in the epithelial cells was also wrinkled to promulgate into the cytoplasm to become basal infoldings producing canaliculi in basal labyrinth formation. There were many mitochondria scattered in these formations as well. On the bottom of the epithelial cell, basal lamina was attached and between basal lamina and muscle bundle was subepithelial space, which is connective tissue. Inside the space, tracheal and nerve cells were observed.

Recessive congenital methemoglobinemia due to nicotinamide adenine dinucleotide (NADH)-cytochrome b5 reductase (b5R) deficiency is classified into 2 clinical types: type 1 (erythrocyte type) and type 2 (generalized type). We found a Chinese family with type 1 recessive congenital methemoglobinemia, the patients from which were diagnosed according to clinical symptoms and b5R enzyme activity in the blood cells. To learn the molecular basis of type 1 recessive congenital methemoglobinemia in this Chinese family, we isolated total RNA from the peripheral leukocytes of the propositus and b5R complementary DNA (cDNA) by reverse transcription– polymerase chain reaction (RT-PCR). The coding region of the b5R cDNA was analyzed by sequencing the cloned PCR products. The results showed that the propositus was homozygous for a G?A transition at codon 203 in exon 7, changing a cysteine to a tyrosine (Cys203Tyr). To characterize the mutant enzyme, both glutathione S-transferase (GST)-fused wild-type b5R and GST-fused mutant Cys203Tyr b5R were expressed in Escherichia coli and affinity purified. The results showed that the catalytic activity of the enzyme was not much affected by this amino acid substitution, but the mutant enzyme exhibited decreased heat stability and increased susceptibility to trypsin. These properties of the mutant enzyme would account for the restricted b5R deficiency and mild clinical manifestations of these type 1 patients. The finding of this novel mutation makes codon 203 the only position within the b5R gene at which more than 1 mutation has been found.

Spherical particles of polyacrylamide-zirconium phosphate (PZP) ion-exchanger have been prepared by the conversion of hydrous zirconia with the sol-gel technique using acrylamide and N,N'-methylenebisacrylamide copolymer as binders. Some chemical properties, stabilities, and sorptions of 1-2 valent cations have been studied. An elution curve of 137Cs is reported, and the effective separation of Cs+, Co2+, and Ce3+ has been achieved with a small column of PZP.

Abstract: Ammonium uranates (AU) obtained by the addition of aqueous NH4 OH to a solution of UO2 (NO3)2 or the equilibrium reaction of UO3 · 2H2 O with the vapour over concentrated NH4 OH have been studied by X-ray diffraction (XRD) analysis, diffuse reflectance Fourier transform infrared spectrometry (DR-FTIR) and chemical analysis. Ammonia can be present as either NH3 or NH 4+ . For precipitates obtained at a pH of 3.7, ammonia in the form of NH3 is predominant. For ammonium uranate obtained by reaction over concentrated NH4OH, most of the ammonia is bonded as NH 4+ . The reaction mechanism and structures of the products are also discussed.

Trace beryllium (Be) in uranium oxide and tap water was determined by electron capture detection. After dissolving, samples were mixed with an ethanol solution of 0.08 N trifluoroacetylacetone (HTFA) to form a single-phase system. The Be(TFA)2 complex that formed was extracted to cydohexane. The excess of free HTFA in cyclohexane was washed with 0.1 M NaHCO3 solution; the effects of organic extractants (solvents), pH value, and shaking time on recovery are also discussed. The detection limit with this method was 2 × 10−11 g of Be. The content of Be in tap water could be determined as low as the sub-ppb order. It was also demonstrated that the fluoride ion interfered with the determination of Be.