Polymer–polymer interaction,in the presence of a solvent as measured by viscometry

Dilute solution viscometry experiments have been carried out in five ternary polymer systems solvent(1)/polymer(2)/polymer(3). Values of the specific viscosity of polymer (3) in a ‘binary solvent’ formed by polymer(2) + solvent(1) have been used to determine the compatibility of the polymer blends. Krigbaum and Wall formalism has been used to predict compatibility which relies on an interaction parameter that depends on the concentration, weight fraction and molar mass of each polymer. To reduce the dependences and to clarify the criterion of compatibility, a parameter independent of polymer (3) composition and molar mass has been deduced. This parameter shows the same behaviour with polymer(2) concentration as the Stockmayer–Fixman parameter B. © 2001 Society of Chemical Industry     

Liquid sourdough fermentation: industrial application perspectives

Sourdough fermentation is considered to play a key role to get improved flavour, texture, nutritional and shelf-life properties of bakery products. Since few years Barilla R&D has been focusing on liquid sourdough fermentation which may deserve several advantages with respect to traditional processes. The results showed that the micro-biota of sourdough markedly influences flavour and texture of bakery products. Particular attention has been paid to lactic acid bacteria and yeasts. Selected lactic acid bacteria and yeasts were tested in sourdough liquid fermentation as single strain or in association. The parameters of fermentations were optimized and standardized to set up a laboratory plant liquid fermentation. Only a few strains of lactic acid bacteria were found to be suitable for liquid fermentation alone or in association with yeasts. Fermentations were carried out at pilot plant and an industrial technology was developed. This work describes the results found for the organoleptic profile of an industrial bread started with liquid sourdough with respect to bakers' yeast bread without sourdough addition.     

Probiotics Enhance Bone Growth and Rescue BMP Inhibition: New Transgenic Zebrafish Lines to Study Bone Health

Zebrafish larvae, especially gene-specific mutants and transgenic lines, are increasingly used to study vertebrate skeletal development and human pathologies such as osteoporosis, osteopetrosis and osteoarthritis. Probiotics have been recognized in recent years as a prophylactic treatment for various bone health issues in humans. Here, we present two new zebrafish transgenic lines containing the coding sequences for fluorescent proteins inserted into the endogenous genes for sp7 and col10a1a with larvae displaying fluorescence in developing osteoblasts and the bone extracellular matrix (mineralized or non-mineralized), respectively. Furthermore, we use these transgenic lines to show that exposure to two different probiotics, Bacillus subtilis and Lactococcus lactis, leads to an increase in osteoblast formation and bone matrix growth and mineralization. Gene expression analysis revealed the effect of the probiotics, particularly Bacillus subtilis, in modulating several skeletal development genes, such as runx2, sp7, spp1 and col10a1a, further supporting their ability to improve bone health. Bacillus subtilis was the more potent probiotic able to significantly reverse the inhibition of bone matrix formation when larvae were exposed to a BMP inhibitor (LDN212854).     

Technological process for a new silicon solar cell structure with honeycomb textured front surface

This paper presents a new silicon solar-cell structure improved by texturisation of the front surface using silicon micromachining technologies. A ‘honeycomb’-textured front surface has been obtained through a photolithographical process to generate patterns (disc holes) on the front surface followed by isotropic etching (in HNO₃: HF: CH₃COOH) until the wells joined together.For front-surface loss characterisation, the spectral dependence of the front-surface reflectivity has been investigated by spectrophotometrical measurements. The surface reflectivity was lowered under 10% and this value was a good one compared to the reflectivity of silicon monocrystalline wafer untextured surface. The p–n junction made by phosphorous diffusion at 0.8 μm follows the honeycomb profile. In order to obtain low series resistance, a p+ boron diffusion on the back of the structure was made. The fabrication process was completed with an ohmic contact (Al on top and on the back surface).     

Intraspecific variations of Dekkera/Brettanomyces bruxellensis genome studied by capillary electrophoresis separation of the intron splice site profiles

In enology, "Brett" character refers to the wine spoilage caused by the yeast Dekkera/Brettanomyces bruxellensis and its production of volatile phenolic off-flavours. However, the spoilage potential of this yeast is strain-dependent. Therefore, a rapid and reliable recognition at the strain level is a key point to avoid serious economic losses. The present work provides an operative tool to assess the genetic intraspecific variation in this species through the use of introns as molecular targets. Firstly, the available partial D./B. bruxellensis genome sequence was investigated in order to build primers annealing to introns 5' splice site sequence (ISS). This analysis allowed the detection of a non-random vocabulary flanking the site and, exploiting this feature, the creation of specific probes for strain discrimination. Secondly, the separation of the intron splice site PCR fragments was obtained throughout the set up of a capillary electrophoresis protocol, giving a 94% repeatability threshold in our experimental conditions. The comparison of results obtained with ISS-PCR/CE versus the ones performed by mtDNA RFLP revealed that the former protocol is more discriminating and allowed a reliable identification at strain level. Actually sixty D./B. bruxellensis isolates were recognised as unique strains, showing a level of similarity below 79% and confirming the high genetic polymorphism existing within the species. Two main clusters were grouped at similarity levels of about 46% and 47%, respectively, showing a poor correlation with the geographic area of isolation. Moreover, from the evolutionary point of view, the proposed technique could determine the frequency of the genome rearrangements that can occur in D./B. bruxellesis populations.     

《应用绿化外墙控制建筑墙面温度》

在新建建筑和既有建筑改造工程中,绿化外墙技术是一种可持续性解决方案,可降低制冷系统的能源需求,缓解城市热岛效应,改善建筑热能效率。绿化墙面可保证建筑物的物理遮阳,促进建筑物夏季蒸汽消散,提升建筑物冬季热保温性能。在意大利的巴里大学进行了为期两年的实验,由多孔砖砌筑的三面垂直墙体得到了测试。其中两面墙体覆盖了常青植物(Pandorea jasminoides variegated and Rhyncospermum jasminoides),另一墙体为光秃秃的墙并用于参照。在实验测试期间收集了关于墙壁和环境条件的几个气候参数。在温暖的日子里,有绿植遮蔽的墙面观察到的日光温度低于未覆盖墙面温度,最高可达9.0℃。在寒冷的日子里,有绿植遮蔽的墙面夜间温度高于参照墙的温度,高达3.5℃。白天外墙的热性能是由太阳辐射、风速和空气相对湿度形成的。在风速为3~4 m/s,空气相对湿度为30%~60%,太阳辐射值高于800 W/m~2时,降温效果最好。     

Biochemical indicators of nutritional status and dietary intake in Costa Rican Cabécar Indian adolescents

The purpose of this study was to determine the blood levels of selected nutritional status indicators and the dietary intake of Costa Rican Cabécar Indians aged 10 to 16 years. The results showed that 65% of the adolescents had an adequate body mass index (BMI) for their age, and 32% had a BMI < 5th percentile. Likewise, the study revealed a high prevalence of anemia (57%), deficient serum folate levels (54%), deficient vitamin B12 levels (31%), and subclinical vitamin A deficiency (10%). Additionally, the youngsters had elevated prevalences of high triglyceride levels (77%), borderline high-density lipoprotein (HDL) cholesterol levels (46%), homocysteine levels > 10 micromol/L (29%), and homozygous mutation of methylenetetrahydrofolate reductase (MTHFR) (49%). The diet was poor, being high in saturated fat and low in polyunsaturated fat, fiber, and several micronutrients. The dietary intakes of more than 55% of the adolescents did not meet 50% of the estimated average requirements (EAR) for zinc, vitamin A, vitamin C, vitamin B12, vitamin B2, and folate. Furthermore, a high prevalence of parasitosis was found (68%). Our results show an adolescent Cabécar population with a mosaic of nutritional deficiencies and cardiovascular risk factors.     

Timing analysis and validation with UML: the case of the embedded MARS bus manager

This paper presents a case study in UML-based modeling and validation of the intricate timing aspects arising in a small but complex component of the airborne Medium-Altitude Reconnaissance System produced by the Netherlands National Aerospace Laboratory. The purpose is to show how automata-based timing analysis and verification tools can be used by field engineers for solving isolated hard points in a complex real-time design, even if the press-button verification of entire systems remains a remote goal. We claim that the accessibility of such tools is largely improved by the use of an UML profile with intuitive features for modeling timing and related properties. This work has been partially funded by the European OMEGA project (IST-2001-33522). Iulian Ober and Ileana Ober: performed work while at VERIMAG, Grenoble, France. Y. Yushtein: at the moment of writing in National Aerospace Laboratory NLR.     

Gelatin-Hyaluronan Click-Crosslinked Cryogels Elucidate Human Macrophage Invasion Behavior

Hydrogel models of metastasis traditionally focus on the invasion of cancer cells; however, other cells in the tumor microenvironment that are associated with metastasis also have the ability to migrate. Macrophage phenotype plays a key role in the tumor microenvironment, yet understanding their migration within tunable 3D in vitro models has been limited. To gain a greater understanding of macrophage invasive behavior, stable and transparent oxime-crosslinked cryogels comprised of click-crosslinked gelatin-oxyamine and hyaluronan-aldehyde (GELox-HAa) are synthesized. Fibronectin-derived, oxyamine-modified PHSRN-RGDSP peptides are incorporated to further mimic the tumor extracellular matrix without impacting cryogel mechanics. It is found that primary human macrophages migrate to a greater depth in cryogels with greater porosity and pore size. To better understand the mechanism of migration, cells are treated with either inhibitors of matrix metalloproteinases (MMPs) or rho-associated protein kinase (ROCK) and a predominantly MMP-mediated mechanism of invasion is found. Macrophage polarization studies reveal that anti-inflammatory, interleukin-4/13 (IL4/IL13)-treated macrophages migrate through cryogels to a greater extent than pro-inflammatory, interferon-gamma/lipopolysaccharide (IFNγ/LPS)-treated cells. Interestingly, polarized macrophages move through cryogels using a combination of amoeboid and mesenchymal migration. These findings of macrophage invasion in this cryogel platform set the stage for their further study in a biomimetic tumor microenvironment.