Xylosidases associated with the cell surface of Penicillium herquei IFO 4674

Penicillium herquei IFO 4674 is a filamentous fungus that produces a large amount of hydrolases for fibrous polysaccharides. We purified two beta-xylosidases, S1 and S2. The molecular masses of S1 and S2 determined by MALDI-TOF-MS were 103,700 and 37,460 Da. The optimum pHs of S1 and S2 were 4.0 and 6.5, respectively. By several kinds of alcohols, especially glycerol, S1 was activated while S2 was unaffected or inhibited. S1 had a transxylosylation activity, while S2 did not. The s2 gene encoding xylosidase S2 was cloned by PCR with primers designed on the basis of partial amino acid sequences of S2. The s2 consisted of 1005 by encoding 335 amino acids (37,433 Da) and had no secretion signal sequence. The deduced amino acid sequence shows a high identity to that of Bacteroides ovatus xylosidase/arabinosidase (56%), which is a member of the family 43 glycoside hydrolase.     

Drying of flowing liquid film on rotating disk

Recently,development of high technology has been required for the formation of uniform thin film
in manufacturing processes of semiconductor as the precision instruments become more
sophisticated.A method called spin coating is often used for spreading photoresist on a wafer surface
and drying photoresist film.In spin coating process,photoresist is uniformly spread on the wafer surface
by centrifugal force caused by rotating wafer.However,it is a serious concern that streaky lines,which
are caused by spiral vortices,appear on the wafer surface and prevent the formation of uniform film in
the case of high rotating speed.On the other hand,in the case of low rotating speed,a small hump of
the film is formed near the wafer edge.The main purpose of this study is to make clear the drying
characteristics of the flowing liquid film on the rotating wafer.Temperature distribution of the flowing
liquid film is captured by an infrared thermal video camera and radial gradient of the film temperature is
introduced in order to evaluate the drying characteristic of the flowing film under steady state
condition.Effects of the flow rate of the liquid film on the film temperature are investigated.The film
temperature gradually decreases in the radial direction in all cases.At low rotating speed,the radial
gradient of the film temperature is almost constant widely.On the other hand,at high rotating
speed,the radial gradient of the film temperature takes a certain maximum value.It is found that the
location of the gradient peak corresponds with the transition region of the air boundary layer,in which
spiral vortices swirl,and shifts to the inner side of the disk with an increase of the liquid flow rate.     

Meta-analysis of net energy return for wind power systems

This analysis reviews and synthesizes the literature on the net energy return for electric power generation by wind turbines. Energy return on investment (EROI) is the ratio of energy delivered to energy costs. We examine 119 wind turbines from 50 different analyses, ranging in publication date from 1977 to 2007. We extend on previous work by including additional and more recent analyses, distinguishing between important assumptions about system boundaries and methodological approaches, and viewing the EROI as function of power rating. Our survey shows an average EROI for all studies (operational and conceptual) of 25.2 (n = 114; std. dev = 22.3). The average EROI for just the operational studies is 19.8 (n = 60; std. dev = 13.7). This places wind in a favorable position relative to fossil fuels, nuclear, and solar power generation technologies in terms of EROI.     

Investigation of boiling hydrogen flow characteristics under low-pressure conditions - Flow regime transition characteristics

Understanding the thermal-fluid characteristics of boiling hydrogen is of great significance for applications of liquid hydrogen, such as alternative clean energy and space vehicles. The boiling temperature of liquid hydrogen under atmospheric pressure is 20.3 K; thus, it is easy to boil to form a gas–liquid two-phase flow. Fuel transfer under the boiling state has been avoided in the space industry because of its unstable flow characteristics; precise control of the fuel, including the boiling flow, is necessary to improve the space-vehicle performance. This study aims to understand the flow-regime transition characteristics of boiling hydrogen through experimental investigation. The experimental conditions were as follows: the flow direction was horizontal, the inner diameter of the heating pipe was 15 mm, the mass flux ranged from 50 to 110 kg/m²s, and the pressure ranged from 250 to 300 kPa A. The flow-regime transition characteristics were obtained by a high-speed camera. Fully liquid phase (LP), dispersed bubbly flow (DB), intermittent flow (IN), and annular flow (AN) were observed during the experiment. Each flow-regime boundary model is constructed using two dominant forces from the experimental result based on a Taitel–Dukler model. For the DB/IN boundary, a large-bubble sustainable condition is derived by the balance between the shear and buoyancy forces acting upon the bubble; for the IN/AN boundary, a droplet-sustainable condition is derived in terms of the force balance between the drag and gravity acting on the droplet. The semi-theoretical model predicts the experimental data with 96.7% accuracy.     

Oral administration of multispecies microbial supplements to sows influences the composition of gut microbiota and fecal organic acids in their post-weaned piglets

The timings of the administration of microbial supplements to control the populations of gut microbiota of piglets have been poorly understood. Here the effects of temporal administering multispecies microbial supplements to sows on the composition of gut microbiota and on the bacteria-mediated fecal metabolites in their offsprings were investigated. During gestation and lactation, pregnant sows were fed either a normal diet (group A) or a diet with multispecies supplements comprised of nine microbial species such as Lactobacillus delbrueckii subsp. bulgaricus, Bifidobacterium bifidum, Enterococcus faecium, Candida pintolopesii, and Aspergillus oryzae etc. (group B). All of the sows' piglets were temporarily fed with the same supplements around weaning in accordance with the guideline of the farm. This regimen was followed by a normal diet in both groups over one month thereafter. Under such conditions, the concentration of short-chain fatty acids (SCFAs) in fecal samples remarkably increased in group B compared to group A. When 16S rDNA sequences of the fecal bacteria were analyzed, the microbial structure of bacteria was different between both goups. Especially the Clostridium cluster IV and subcluster XIVa were particularly increased in group B, although the administered microbes were undetectable. Thus, temporal administration of multispecies-microbial supplements to pregnant sows changes the composition of SCFAs and gut microbiota in their offsprings.     

Selenium moderates mercury toxicity in free-ranging freshwater fish

Due to the extremely high affinity of selenium (Se) to mercury (Hg), Se sequesters Hg and reduces its biological availability in organisms. However the converse is also true. Hg sequesters Se, causing Hg to inhibit the formation of Se dependent enzymes while supplemental Se supports their continued synthesis. Hence, whether or not toxic effects accompany exposure to Hg depends upon the tissue Se:Hg molar ratio of the organism. The main objective of the present study was to investigate how levels of Hg and Se affected metallothionein (MT) induction in free-ranging brown trout, Salmo trutta, from Lake Mj?sa, Norway (a Se depauperate lake). MT is proposed as a sensitive biomarker of potential detrimental effects induced by metals such as Hg. Emphasis was addressed to elucidate if increased tissue Se:Hg molar ratios and Se levels affected the demands for MT in the trout. The Se:Hg molar ratio followed by tissue Se levels were most successful for assessing the relationship between metal exposure and MT levels in the trout. Thus, Hg in molar excess over Se was a stronger inducer of MT synthesis than tissue Hg levels in the trout, supporting the assumption that Se has a prominent protective effect against Hg toxicity. Measuring Hg in animals may therefore provide an inadequate reflection of the potential health risks to humans and wildlife if the protective effects of Se are not considered.     

Broad-band extreme ultraviolet lithography with a wet-silylated and dry-developed resist

Broad-band extreme ultraviolet (1340nm) lithography (EUVL) has been examined. Exposure intensity at the broad-band of 1340nm was 20 times larger than at the conventional narrow-band of 13nm. Moreover, broad-band EUVL with a wet-silylated and dry-developed resist process has been investigated in order to obtain a high resolution of 0.1μm with high-aspect-ratio. Imaging experiments were performed using 32:1 reduction Schwarzschild optics illuminated with a synchrotron radiation light source from SORTEC ring. The exposure was done through a 0.1μm-thick SiN vacuum window, Mo/Si multilayer coated optics and without a Be filter. Silylation characterization and determination of optimum composition of the silylation solution have been performed using Fourier transform infrared spectroscopy (FTIR). Using broad band EUVL with the optimal wet-silylated and dry-developed resist, 0.1μm lines and spaces of 0.55μm-thick resist (aspect RATIO = 5.5) can be successfully delineated.     

Thermophysical and mechanical properties of CrB and FeB

ABSTRACT

Fuel debris in the Fukushima Daiichi nuclear power plant is thought to contain borides that are generated from B₄C control material. In order to successfully devise methods to effectively remove the debris material, characterization of the properties of the fuel debris is essential. This paper presents some of the thermophysical and mechanical properties of two types of borides, FeB and CrB, and compares them with those of Fe₂B and ZrB₂. These are the representative borides that might have been generated in the Fukushima Daiichi (1F) nuclear power plant accident. We observed that the thermal conductivity values of both CrB and FeB are much lower than that of ZrB₂, and are similar to that of Fe₂B. Moreover, the Vickers hardness and fracture toughness of FeB and CrB are almost identical to each other, and similar to those of ZrB₂ and Fe₂B.     

Ribosomal Synthesis of Cyclic Peptides with a Fluorogenic Oxidative Coupling Reaction

Ring around the peptides : We demonstrate a new method for the cyclization of peptides that involves the oxidative coupling of 5‐hydroxyindole and benzylamine. After two nonproteinogenic amino acids were incorporated into peptides by reprogramming the genetic code, cyclization took place rapidly upon the addition of K₃Fe(CN)₆ and generated a conjugated, fluorescent, heterocyclic structure.