Effects of Brain Size on Adult Neurogenesis in Shrews

Shrews are small animals found in many different habitats. Like other mammals, adult neurogenesis occurs in the subventricular zone of the lateral ventricle (SVZ) and the dentate gyrus (DG) of the hippocampal formation. We asked whether the number of new generated cells in shrews depends on their brain size. We examined Crocidura russula and Neomys fodiens, weighing 10–22 g, and Crocidura olivieri and Suncus murinus that weigh three times more. We found that the density of proliferated cells in the SVZ was approximately at the same level in all species. These cells migrated from the SVZ through the rostral migratory stream to the olfactory bulb (OB). In this pathway, a low level of neurogenesis occurred in C. olivieri compared to three other species of shrews. In the DG, the rate of adult neurogenesis was regulated differently. Specifically, the lowest density of newly generated neurons was observed in C. russula, which had a substantial number of new neurons in the OB compared with C. olivieri. We suggest that the number of newly generated neurons in an adult shrew’s brain is independent of the brain size, and molecular mechanisms of neurogenesis appeared to be different in two neurogenic structures.     

Effect of the degree of fusariosis on the physical characteristics of individual wheat kernels

This work aims to determine dependencies of single‐kernel (SK) physical traits on the kernel degree of fusariosis. The measurements were taken on samples of grain of six wheat varieties cultivated during 1–3 years. For SK mass, volume and width this dependence resulted in lowered (by at least ten to more than 25% for mass and volume, and ca. 5 to more than 15% for width) values in Fusarium culmorum infested grain as compared with the non‐inoculated control. In addition, moderately infested kernels tended to be of higher mass and size than kernels with no symptoms of infestation. An unexpected effect was a lack of dependence of SK density on the degree of infestation. Moisture content was lower for infested kernels by 6–8%, hardness tended to increase a little for moderate infestation, while it noticeable decreased for the heaviest infestation.     

Mechanical and Infrared Thermography Analysis of Shape Memory Polyurethane

Multifunctional new material—polyurethane shape memory polymer (PU-SMP)—was subjected to tension carried out at room temperature at various strain rates. The influence of effects of thermomechanical couplings on the SMP mechanical properties was studied, based on the sample temperature changes, measured by a fast and sensitive infrared camera. It was found that the polymer deformation process strongly depends on the strain rate applied. The initial reversible strain is accompanied by a small drop in temperature, called thermoelastic effect. Its maximal value is related to the SMP yield point and increases upon increase of the strain rate. At higher strains, the stress and temperature significantly increase, caused by reorientation of the polymer molecular chains, followed by the stress drop and its subsequent increase accompanying the sample rupture. The higher strain rate, the higher stress, and temperature changes were obtained, since the deformation process was more dynamic and has occurred in almost adiabatic conditions. The constitutive model of SMP valid in finite strain regime was developed. In the proposed approach, SMP is described as a two-phase material composed of hyperelastic rubbery phase and elastic-viscoplastic glassy phase, while the volume content of phases is specified by the current temperature.     

Peptides inhibitory to endopeptidase and aminopeptidase fromLactococcus lactis ssp.lactis MG1363, released from bovineβ-casein by chymosin,trypsin or chymotrypsin

Peptides inhibitory to the 70-kDa endopeptidase (PepO) from the cytoplasm ofLactococcus lactis ssp.lactis MG1363 were isolated from the supernatant (pH 4.6) of chymosin, tryptic and α-chymotryptic hydrolysates ofβ-casein (β-CN) by reversed-phase HPLC and identified by sequencing and mass spectrometry. Chymosin releasedβ-CN f193–209, kinetic constant (K _i) of which for inhibition of PepO was 60 μM. This peptide also inhibited (K _i=1700 μM) the 95-kDa aminopeptidase (PepN) fromL. lactis ssp.lactis MG 1363. Trypsin released two PepO-inhibitory peptides: one,β-CN f69–97, was not degradable by PepO (K _i=4.7 μM), while the other,β-CN f141–163, was degradable by PepO but competitively inhibited hydrolysis of methionine enkephalin by PepO. A peptide,β-CN f69–84, which inhibited PepO with aK _i of 8.1 μM, was isolated from the α-chymotryptic hydrolysate. Peptides released fromβ-CN by trypsin or chymotrypsin had very little inhibitory activity against PepN. PepO degradedβ-CN f193–209 very slowly compared with the hydrolysis of methionine enkephalin. All four inhibitory peptides (β-CN f193–209, f69–97, f69–84, f141–163) were readily degraded by thermolysin.     

Mechanised welding of tubes to tubeplates

Abstract

With the introduction of the Ministerial Decree of 24 November 1984, which allows the use of polyethylene in the construction of underground pipelines for gas transportation, the said material and the relevant tvelding techniques have undergone considerable development in Italy.

This paper describes the main characteristics of this unusual plastic and indicates the welding processes normally used for joining P E pipes and fittings.

The accent is placed on the present possibilities of destructive and non-destructive testing of the welded joints, and an outline is given of the new Italian plan for the qualification of welders of polyethylene, prepared by UNIPLAST in conjunction with the Italian Welding Institute.     

LTCC Microfluidic System

A simple and inexpensive low-temperature cofired ceramic (LTCC) microfluidic device with integrated optical fibers is designed, manufactured, and tested with positive results. Fluidic channels, mixer, detector, optical fiber, light source, light detector, heater, and temperature sensor are integrated in one LTCC module. The optical system in the LTCC microsystem permits measurements of light transmittance and fluorescence. The design, technology, and results of the module's evaluation are presented.     

大坝失稳的风险

假定保持大坝稳定和使用大坝失稳的力确定在15％精度范围内，并使用误差附加原则和高斯分布，求出水工建筑物失事概率为0．006，该值远远超过了由于洪水而引起失事的概率，提出了失事概率评价方法使用大坝设计可以使用比假定的a值低的总体失事概率。     

Adsorption of H2 on Alkali Metal Substrates

Adsorption of H₂ on Li and Cs substrates at low temperature is investigated theoretically by means of Density Functional and Path Integral Monte Carlo calculations. Qualitative and semi-quantitative agreement is observed between the two methods. Adsorption on Li is observed to occur through completion of successive solid layers, whereas resugts for a Cs substrate are consistent with absence of wetting at low temperature.     

Investigation of flow boiling in horizontal tubes: Part I—A new diabatic two-phase flow pattern map

Several important modifications to the flow pattern map of Kattan-Thome-Favrat [J. Heat Transfer 120(1) (1998) 140-147] made, resulting in a significantly new version of the map. Based on the dynamic void fraction measurements described in [Int. J. Multiphase Flow 30 (2004) 125-137], the stratified-wavy region has been subdivided into three subzones: slug, slug/stratified-wavy and stratified-wavy. Furthermore, annular-to-dryout and dryout-to-mist flow transition curves have been added and integrated into the new flow pattern map, identified by distinct trends of the heat transfer coefficient as a function of vapor quality and by flow pattern observations to determine (and then predict) the inception and completion of dryout in horizontal tubes.     

Microchannel fabrication process in LTCC ceramics

This paper describes a simple method of fluidic microchannel fabrication in low temperature co-fired ceramic (LTCC) substrates. This method is based on a new two-step lamination process with using sacrificial volume material (SVM) materials. The research is carried out for five different microchannel widths (100 μm, 200 μm, 500 μm, 1 mm and 5 mm). The test structures are manufactured using three different lamination pressures (50, 100 and 200 atmospheres) and two different SVM materials – carbon-black paste and cetyl alcohol. The resulting structures’ mechanical properties are analyzed using a scanning electron microscope (SEM).