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ABSTRACTCandidaspecies are the most commonly isolated opportunistic fungal pathogens in humans. Candida albicanscauses most of the diagnosed infections, closely followed by Candida glabrata. C. albicansis well studied, and many genes have been shown to be important for infection and colonization of the host. It is however less clear how C. glabratainfects the host. With the help of fungal RNA enrichment, we here investigated for the first time the transcriptomic profile of C. glabrataduring urinary tract infection (UTI) in mice. In the UTI model, bladders and kidneys are major target organs and therefore fungal transcriptomes were addressed in these organs. Our results showed that, next to adhesins and proteases, nitrogen metabolism and regulation play a vital role during C. glabrataUTI. Genes involved in nitrogen metabolism were upregulated and among them we show that DUR1,2(urea amidolyase) and GAP1(amino acid permease) were important for virulence. Furthermore, we confirmed the importance of the glyoxylate cycle in the host and identified MLS1(malate synthase) as an important gene necessary for C. glabratavirulence. In conclusion, our study shows with the support of in vivotranscriptomics how C. glabrataadapts to host conditions.

Abstract This paper describes the key geotechnical parameters required for the design of mine shaft linings which are frequently encountered in accessing evaporite deposits and particularly in potash mining. Methods [...]

Numerous field studies have investigated the effects of mulching on soil wind erosion. However, little is known about the changes in soil erodibility after removing the mulch layer. In this paper, we measured the physicochemical properties and aggregate characteristics of soil from an urban park after removing the mulch layer and estimated wind-erodible materials emission by wind tunnel experiments. Wood chips at 4,500 g m−2(mulch thickness of 5 cm, R5), 6,300 g m−2(mulch thickness of 7 cm, R7), and 8,100 g m−2(mulch thickness of 9 cm, R9) were used for mulching an area in Yuanmingyuan Park from October of 2019 to the end of February of 2021. The following four treatments were listed: unmulched soil (CK), R5, R7, and R9. Compared with CK, the soil moisture content (SM), the macroaggregates (>0.25 mm) ratio (M > 0.25), the wind erodible fraction (WEF), and the dry aggregate stability (DAS) of R5, R7, and R9 were significantly increased after mulching (P< 0.05), whereas the soil organic matter content (SOM) was only slightly increased. The calcium carbonate contents (CaCO3) varied greatly among the different treatments. Based on the wind tunnel experiments, the distribution of wind erosion materials near the soil surface (0 to 30 cm) was fitted to logarithmic, power, and exponential functions (R2ranged between 0.7179 and 0.9859). The particle size distribution of all wind-erodible materials was unimodal, and the proportion of coarse particles (250 to 100 μm) was highest. Compared with the CK, the average wind erosion rate (AWER) of R5, R7, and R9 was decreased by 48.44%, 65.04%, and 70.03%, respectively, after mulching. The AWER was significantly (P< 0.01) negatively correlated with SM, M > 0.25, WEF, and DAS, and negatively correlated with CaCO3and SOM. The CaCO3was significantly (P< 0.05) positively correlated with M > 0.25, WEF, and DAS. Overall, despite the relatively short mulching period (16 months), wood chip mulch improved the physicochemical properties and aggregate characteristics of soil and decreased erodibility.

We have developed a new class of sodium carbonate/silicone composite sorbents that selectively capture carbon dioxide (CO2) and can purify biogas to natural gas pipeline-quality biomethane. These nontoxic composites can be three-dimensionally printed or extruded at low costs, can have high specific CO2sorption rates (in excess of 5 μmol s–1g–1bar–1) and high selectivity due to their chemical mechanism, and can be regenerated with low-energy air stripping. Therefore, these composite sorbents combine the high selectivity of liquid sorbents with the high specific sorption rates and low regeneration energies found in many solid sorbents. We characterized these composite sorbents with X-ray computed tomography, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Furthermore, we measured composite sorption capacities of up to 0.62 mol CO2kg–1and recorded breakthrough curves in a flow-through, fixed-bed reactor using both simulated biogas and locally sourced industrial biogas. Additional tests of the composite sorbent were carried out with pure CO2in a sealed pressure drop apparatus. This experimental data was used to validate a numerical model of the setup and to simulate an industrial-scale biogas upgrading process. Finally, we performed a preliminary technoeconomic analysis for this upgrading process and found that this composite sorbent can upgrade biogas at a lower cost (∼$0.97 per GJ) than other currently implemented techniques.

Direct ink writing (DIW) three-dimensional (3D) printing provides a revolutionary approach to fabricating components with gradients in material properties. Herein, we report a method for generating colloidal germania feedstock and germania–silica inks for the production of optical quality germania–silica (GeO2–SiO2) glasses by DIW, making available a new material composition for the development of multimaterial and functionally graded optical quality glasses and ceramics by additive manufacturing. Colloidal germania and silica particles are prepared by a base-catalyzed sol–gel method and converted to printable shear-thinning suspensions with desired viscoelastic properties for DIW. The volatile solvents are then evaporated, and the green bodies are calcined and sintered to produce transparent, crack-free glasses. Chemical and structural evolution of GeO2–SiO2glasses is confirmed by nuclear magnetic resonance, X-ray diffraction, and Raman spectroscopy. UV–vis transmission and optical homogeneity measurements reveal comparable performance of the 3D printed GeO2–SiO2glasses to glasses produced using conventional approaches and improved performance over 3D printed TiO2–SiO2inks. Moreover, because GeO2–SiO2inks are compatible with DIW technology, they offer exciting options for forming new materials with patterned compositions such as gradients in the refractive index that cannot be achieved with conventional manufacturing approaches.

We encapsulated six solvents with novel physical and chemical properties for CO2sorption within gas-permeable polymer shells, creating Micro-Encapsulated CO2Sorbents (MECS), to improve the CO2absorption kinetics and handling of the solvents for postcombustion CO2capture from flue gas. The solvents were sodium carbonate (Na2CO3) solution, uncatalyzed and with two different promoters, two ionic liquid (IL) solvents, and one CO2-binding organic liquid (CO2BOL). We subjected each of the six MECS to multiple CO2absorption and regeneration cycles and measured the working CO2absorption capacity as a function of time to identify promising candidate MECS for large-scale carbon capture. We discovered that the uncatalyzed Na2CO3and Na2CO3-sarcosine MECS had lower CO2absorption rates relative to Na2CO3-cyclen MECS over 30 min of absorption, while the CO2BOL Koechanol appeared to permeate through the capsule shell and is thus unsuitable. We rigorously tested the most promising three MECS (Na2CO3-cyclen, IL NDIL0309, and IL NDIL0230) by subjecting each of them to a series of 10 absorption/stripping cycles. The CO2absorption curves were highly reproducible for these three MECS across 10 cycles, demonstrating successful absorption/regeneration without degradation. As the CO2absorption rate is dynamic in time and the CO2loading per mass varies among the three most promising MECS, the process design parameters will ultimately dictate the selection of MECS solvent.

Cancer stem cells (CSCs), which are a rare population in any type of cancer, including colon cancer, are tumorigenic and responsible for cancer recurrence and metastasis. CSCs have been isolated from a number of different solid tumors recently, although the isolation of CSCs in colon cancer is still challenging. We cultured colon cancer cells in stem cell medium to obtain colonosphere cells. These cells possessed the characteristics of CSCs, with a high capacity of tumorigenicity, migration and invasion in vitroand in vivo. The isolation and identification of CSCs have provided new targets for the therapeutics. Oncolytic herpes simplex viruses (oHSV) are an effective strategy for killing colon cancer cells in preclinical models. Here, we examined the efficacy of an oncolytic herpes simplex virus type 2 (oHSV2) in killing colon cancer cells and colon cancer stem-like cells (CSLCs). oHSV2 was found to be highly cytotoxic to the adherent and sphere cells in vitro, and oHSV2 treatment in vivosignificantly inhibited tumor growth. This study demonstrates that oHSV2 is effective against colon cancer cells and colon CSLCs and could be a promising strategy for treating colon cancer patients.

ABSTRACTRNA-seq data analysis has revealed abundant alternative splicing in eukaryotic mRNAs. However, splicing is only one of many processing events that transcripts may undergo during their lifetime. We present here RNAprof (RNA profile analysis), a program for the detection of differential processing events from the comparison of RNA-seq experiments. RNAprof implements a specific gene-level normalization procedure and compares RNA-seq coverage profiles at nucleotide resolution to detect regions of significant coverage differences, independently of splice sites or other gene features. We used RNAprof to analyze the effect of alternative-splicing regulators NSRa and NSRb on the Arabidopsis thalianatranscriptome. A number of intron retention events and alternative transcript structures were specifically detected by RNAprof and confirmed by qRT-PCR. Further tests using a public Mus musculusRNA-seq dataset and comparisons with other RNA isoform predictors showed that RNAprof uniquely identified sets of highly significant processing events as well as other relevant library-specific differences in RNA-seq profiles. This highlights an important layer of variation that remains undetected by current protocols for RNA-seq analysis.

Controlled self-renewal and differentiation of hematopoietic stem/progenitor cells (HSPCs) are critical for vertebrate development and survival. These processes are tightly regulated by the transcription factors, signaling molecules and epigenetic factors. Impaired regulations of their function could result in hematological malignancies. Using a large-scale zebrafish N-ethyl-N-nitrosourea mutagenesis screening, we identified a line named LDD731, which presented significantly increased HSPCs in hematopoietic organs. Further analysis revealed that the cells of erythroid/myeloid lineages in definitive hematopoiesis were increased while the primitive hematopoiesis was not affected. The homozygous mutation was lethal with a median survival time around 14–15 days post fertilization. The causal mutation was located by positional cloning in the c-cblgene, the human ortholog of which, c-CBL, is found frequently mutated in myeloproliferative neoplasms (MPN) or acute leukemia. Sequence analysis showed the mutation in LDD731caused a histidine-to-tyrosine substitution of the amino acid codon 382 within the RING finger domain of c-Cbl. Moreover, the myeloproliferative phenotype in zebrafish seemed dependent on the Flt3 (fms-like tyrosine kinase 3) signaling, consistent with that observed in both mice and humans. Our study may shed new light on the pathogenesis of MPN and provide a useful in vivovertebrate model of this syndrome for screening drugs.

Background/Objectives:: Studies suggest that the Mediterranean-style diet (MSD) may improve glucose metabolism in patients with type 2 diabetes (T2D), but the results are inconsistent. We conducted a meta-analysis of randomized controlled trials (RCTs) to explore the effects of MSD on glycemic control, weight loss and cardiovascular risk factors in T2D patients. Subjects/Methods:: We performed searches of EMBASE, Cochrane Library and PubMed databases up to February 2014. We included RCTs that compared the MSD with control diets in patients with T2D. Effect size was estimated as mean difference with 95% confidence interval (CI) by using random effect models. Results:: The meta-analysis included nine studies with 1178 patients. Compared with control diets, MSD led to greater reductions in hemoglobin A1c (mean difference, −0.30; 95% CI, −0.46 to −0.14), fasting plasma glucose (−0.72 mmol/l; CI, −1.24 to −0.21), fasting insulin (−0.55 μU/ml; CI, −0.81 to −0.29), body mass index (−0.29 kg/m2; CI, −0.46 to −0.12) and body weight (−0.29 kg; CI, −0.55 to −0.04). Likewise, concentrations of total cholesterol and triglyceride were decreased (−0.14 mmol/l; CI, −0.19 to −0.09 and −0.29 mmol/l; CI, −0.47 to −0.10, respectively), and high-density lipoprotein was increased (0.06 mmol/l; CI, 0.02 to 0.10). In addition, MSD was associated with a decline of 1.45 mm Hg (CI, −1.97 to −0.94) for systolic blood pressure and 1.41 mm Hg (CI, −1.84 to −0.97) for diastolic blood pressure. Conclusions:: The present meta-analysis provides evidence that MSD improves outcomes of glycemic control, body weight and cardiovascular risk factors in T2D patients.

In this Letter, an advanced multilayer photo-aligned liquid crystal polymer (LCP) thin-film structure with multiple optical functions is introduced. Within each LCP layer, a spatially distribution of local optical axes can be controlled by a patterned photo-alignment layer. As an embodiment of the proposed structure, a two-layer structure with pixelated controlled light-propagation directions and polarizations has been studied, which has shown the potential to be used as a photomask for generating multi-domain photo-alignment structures with a single exposure step. The combination of the multilayer structure with patterned photo-alignment technology provides a new perspective of designing optical structures for polarizing photonics applications.

In this article, we disclose a method to fabricate a liquid crystal (LC) Fresnel zone lens (FZL) with high efficiency. The LCFZL, based on patterned planar-aligned regions, has been prepared by means of a two-step photoalignment technique. The proposed binary-phase LCFZL manifests 39% diffraction efficiency at the focal point, which is close to the theoretical limit, 41%. Moreover, because of a lower driving voltage and faster response time, these elements could find application in many modern devices.

We report a technique to coat polymers onto 3D surfaces distinct from traditional spray, spin, or dip coating. In our technique, the surface of a template structure composed of poly(lactic acid) swells and entraps a soluble polymer precursor. Once entrapped, the precursor is cured, resulting in a thin, conformal membrane. The thickness of each coating depends on the coating solution composition, residence time, and template size. Thicknesses ranged from 400 nm to 4 μm within the experimental conditions we explored. The coating method was compatible with a range of polymers. Complicated 3D structures and microstructures of 10 μm thickness and separation were coated using this technique. The templates can also be selectively removed, leaving behind a hollow membrane structure in the shape of the original printed, extruded, or microporous template structures. This technique may be useful in applications that benefit from three-dimensional membrane topologies, including catalysis, separations, and potentially tissue engineering.

A method is reported to prepare siloxane microballoons that can be loaded into a direct ink write siloxane ink for 3D printing. The resulting structure is subjected to a solvent removal and supercritical drying process to provide a final printed siloxane having both macroscopic and microscopic porosity. Core-shell particles are generated by an emulsion template and phase separation process. Intra-strand closed-cell porosities can be achieved between 10 and 40 vol% thus facilitating additional compressive strain before lockup. Short term compression set testing highlights the excellent shape retention properties of these elastomers, which have less than 8% relative compression set under load.

Natural systems employ microvascular exchangers with circular packing for both heat and mass transfer that closely conform to the compact, packing of circles of two diameter. Mathematical descriptions of these systems exist, but have rarely been studied in three dimensions for their exchange properties. We focus on four close packed patterns: “Hexagonal” “Dodecagonal”, “Squarer”, and “Double Squarer”. While two of these patterns have natural analogs, the others are abiological. We compare computationally and experimentally the mass and heat transfer characteristics of these various patterns. Intriguingly the “Double Squarer” pattern, had the highest transfer rates within our fabrication constraints.

Purpose – The flying capacitor converter (FFC) balances the clamping capacitor voltages naturally when phase shifted carrier modulation is used. Several models that describe this mechanism, and to estimate the time constants following a perturbation, are discussed in the literature. However, due to the model complexity, numerical methods must be used to evaluate these models. This paper aims to present a closed form expression, using a reference table, that describes a maximum bound for the voltage balancing time constant. Design/methodology/approach – The FCC is analysed in the frequency domain. A decomposition of the characteristic matrix that describes the voltage balancing mechanism is used. The resulting real symmetric matrix is factorised by using approximations of the load characteristics at the frequencies of interest. Findings – The minimum eigenvalue of the factorised matrix is used to determine a maximum bound for the time constant of the voltage balancing. Since the factorised matrix is independent of variations in switching frequency and load, the eigenvalue of interest can be calculated once and tabulated. Originality/value – The closed form expression can be used for quick calculations of the maximum time constant under different operating conditions. Furthermore, the expression provides considerable insight into the influences circuit design choices have on the balancing mechanism. [ABSTRACT FROM AUTHOR]

Purpose – The flying capacitor converter (FFC) balances the clamping capacitor voltages naturally when phase shifted carrier modulation is used. Several models that describe this mechanism are discussed in the literature. However, due to the model complexity, the stability of the mechanism is inferred from the circuit operation. This paper aims to show that the expressions describing the balancing mechanism can be simplified and used to prove Lyapunov stability. Design/methodology/approach – The FCC is analysed in the frequency domain. An equivalent circuit that describes the converter operation in terms of total and difference parameters is used. A concerted effort is made to simplify the resulting convolution expressions to their most basic forms by using the characteristics of the phase shifted switching functions' Fourier series coefficients. Findings – It is shown that the system matrix decomposes naturally into the sum of a symmetric and a skew-symmetric matrix. Through use of Lyapunov's theorem it is shown that the system is stable if the symmetric part of the decomposition is positive definite. A proof is provided that this matrix is positive semidefinite and the system is therefore Lyapunov stable. Research limitations/implications – The simplified expressions describing the convolution and the decomposition of the system matrix can be used in future studies to provide maximum bounds on the rebalancing time constant. Originality/value – This study provides a proof that the natural voltage balancing mechanism is stable. This stability had to be inferred from circuit operation in previous studies. Secondly, the decomposition of the system matrix provides an avenue for future research. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria (LAB) are extensively used in the food industry for fermentation processes. However, it is possible that these bacteria may serve as a reservoir for antibiotic resistance genes that can be transferred to pathogens, giving rise to public health concerns. Animal operations that use antimicrobials as growth promotants have been linked to the origin of resistance due to the selective effect of low levels of antimicrobial used in this management strategy. The objective of this study was to determine the antimicrobial susceptibilities and mechanisms of resistance for 30 isolates of meat starter cultures commonly used in dry sausage fermentations to 20 antimicrobial agents. Susceptibility tests were performed by broth microdilution using Iso-Sensitest broth (90%, vol/vol) and de Man Rogosa Sharpe (MRS) broth (10%, vol/vol). The results showed that all 30 isolates exhibited resistance to at least three antimicrobials regardless of antimicrobial class while 17 or 30% of strains were resistant to antibiotics in three or six different classes, respectively. The incidence of antimicrobial resistance was higher among Pediococcus pentosaceusand lower for Staphylococcus carnosusstrains. Genetic determinants for the lincosamide, macrolide, and tetracycline antimicrobials were not found using PCR. Phenotypic resistance in the absence of known resistance genes found here suggests that other mechanisms or genes might have contributed to the negative results. Further studies are needed to explore the genetic mechanisms underlying the prevalence of antibiotic resistance in Pediococcusspecies.

Using the sol‐gel method a series of nonstoichiometric nanosilica doped with the rare earth element Ce (CexSi1–xO2–δ, x= 0.0–0.14) were prepared in order to modify the physicochemical properties of the nanosilica surface and to enhance the strength of the Ce‐nanosilica/polysulfone composite membranes. The CexSi1–xO2–δsamples were characterized by Fourier transform infrared spectra, X‐ray diffraction and X‐ray photoelectron spectra. The observations from these characterizations suggest that most Ce atoms enter the silica framework to form a Ce‐O‐Si solid solution while the cubic CeO2phase is segregated when x>0.08. Transmission electron microscopy images show that CexSi1–xO2–δparticles are spherical with a uniform size distribution in the range of 30–50 nm and contain some inner pores with sizes up to a few nanometers. Specifically, Ce0.08Si0.92O2–δ‐700 calcined at 700 °C shows the biggest surface area, the smallest pore size and the highest hydrophilicity, which makes the Ce0.08Si0.92O2–δ/polysulfone composite membranes (8.0 wt %) exhibit the strongest mechanical strength (3.223 MPa), which is enhanced by more than 100% in comparison with the pure polymer membrane.

AbstractUse of alcohol in Africa, particularly in South Africa, has a long history and is a way of life for many people, regardless of their socio-economic background. Alcohol abuse has many negative economic, social and health consequences. The objective of this review is to present in brief the history of alcohol use and the social and economic causes and consequences of alcohol abuse in South Africa. Research has shown that the socio-economic effects associated with alcohol abuse include unemployment, violence, crime, sexual risk behaviour and disruptions to family life and work performance. These effects are discussed by emphasising that social and economic changes stemming from urbanisation account for new patterns of drinking among most Africans. South African legislation pertaining to alcohol is also discussed in order to highlight the need for changing or amending certain acts if alcohol abuse is to be reduced.

AbstractObjective:There is evidence showing a cardioprotective effect of light to moderate alcohol consumption in many populations. Whether alcohol consumption reduces cardiovascular disease (CVD) risk in an African population remains unclear. This study therefore assessed the associations between alcohol consumption (using reported alcohol intake and biological alcohol consumption markers) and CVD risk factors in an African population in transition.Design:This cross-sectional epidemiological survey is part of the South African segment of the international 12-year Prospective Urban and Rural Epidemiology (PURE) study in which the health transition in urban and rural subjects is investigated.Setting:A rural and urban site in the North West Province of South Africa.Subjects:A total of 2010 apparently healthy African volunteers (35 years and older) were recruited from a sample of 6000 randomly selected households.Methods:Alcohol consumption was assessed by a validated quantitative food frequency questionnaire (QFFQ) and two biological markers, percentage serum carbohydrate-deficient transferrin (%CDT) and gamma-glutamyl transferase (GGT). The cardiovascular risk factors included in this analysis were serum lipids and blood pressure. Complete data of 1763 and 1878 participants were available for %CDT and GGT respectively. The subjects were divided into quartiles on the basis of their reported alcohol consumption (QFFQ), %CDT and GGT values. Additionally, subjects were divided into self-reported drinkers and non-drinkers. Men and women were analysed separately.Results:The two alcohol biomarkers %CDT and GGT had different associations with CVD risk factors in this population. The risk of CVD decreased with increasing %CDT level, in that high-density lipoprotein cholesterol (HDL-C) increased significantly with increasing %CDT concentrations for both men and women. There was no significant increase in blood pressure, triglycerides and total cholesterol with increasing %CDT concentrations, except for women, where blood pressure increased significantly with %CDT. Blood pressure, triglycerides and total cholesterol increased significantly with increasing GGT concentrations for both men and women. GGT was also positively associated with HDL-C for both men and women. Self-reported drinkers had a significantly higher HDL-C, blood pressure, %CDT, GGT and lower body mass index (BMI) values than self-reported non-drinkers for both men and women. No significant differences between self-reported drinkers and non-drinkers were seen for triglycerides and total serum cholesterol (even after adjusting for BMI and smoking) for both men and women.Conclusions:In this population-based study, increased alcohol consumption was associated with higher HDL-C levels but also with increased blood pressure values, indicating that the cardioprotective effect of alcohol possibly may disappear because the increase in blood pressure offsets the benefits of the increase in HDL-C.

AbstractThe World Health Organization recently stated that alcohol consumption is the fifth leading cause of death worldwide and that intakes are increasing, especially in developing countries. Alcohol-related effects are major threats to global public health. There is growing recognition of an association between alcohol abuse and a host of health and social problems in many parts of the world. In South Africa, a developing country with a rapidly growing economy, available evidence shows that alcohol is a leading risk factor for mortality and morbidity, and hence a significant contributor to the burden of disease. The observed pattern of binge drinking of about a third of South African drinkers is of concern. In addition to physical dependence on alcohol, other psychological, genetic and social factors may contribute to the development of alcohol-related diseases. To develop a relevant, integrated and coherent strategy to address alcohol use, misuse and abuse in South Africa, we need a much better understanding of the metabolism of alcohol, and how the metabolic products and changes associated with alcohol abuse ultimately lead to biological health hazards. This review offers a broad understanding of the metabolism of alcohol and the biological health hazards associated with its abuse. Levels of foetal alcohol syndrome in South Africa are the highest ever recorded, and hence this review will separately address teratogenic effects associated with abuse.

In order to selectively separate luteolin from its crude solution, we synthesized imprinted porous materials with high recognition specificity for luteolin, using an imprinting technique. Modified luteolin was used as template, vinyltriethoxysilane as the functional monomer, and tetraethyl orthosilicate (TEOS) as the cross‐linking agent. The results showed the following optimum reaction conditions: The reaction ratio between luteolin and acryloyl chloride was 1 : 2 (0.10 g/0.20 g), adding 1.0 g precursor; the feasible elution time was 12 h; when the molar quantity of modified template molecule was 0.01 mol and ethenyltriethyloxy‐silane (VTEO) was 0.04 mol, the maximum yield reached 91.6 %. All samples were tested by Brunauer‐Emmett‐Teller method, Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy, equilibrium adsorption experiments and selective adsorption experiments. It was found that the imprinted porous materials showed excellent selectivity for luteolin in aqueous solution. Characterization by FTIR suggested that an addition reaction had occurred between the modified template molecule and VTEO while forming ester bonds in the functional precursor. Results from pore structure analysis indicated that the imprinted porous materials had good channels, and the average pore size of the prepared porous materials was between 35.85 and 95.82 Å. Adsorption dynamics analysis suggested that, when the adsorption time reached 3 h, the adsorption process had reached balance and the adsorption capacity was at steady state. These porous materials had highly selective recognition properties and high equilibrium adsorption capacity for the template molecule. The equilibrium adsorption capacity of the imprinted porous materials to the template molecule was 11.4 times that of the blank porous materials.

Chemical mechanical polishing of tantalum was carried out in alumina-dispersed deionized water, 5% H2O2as well as 0.25 M KIO3solution at pH ranging from 1 to 10. High polishing rates were observed in H2O2-containing slurry at low pH values, while KIO3slurry showed no appreciable effect of pH and the polishing rates were low. While tantalum pentoxide readily forms in either slurry, electrochemical observations indicate a higher dissolution rate of the oxide in H2O2slurry, particularly at low pH accounting for the greater polishing rate.

With the trends of e-commerce and globalization occurring in the economy, an effective global supply chain (GSC) management has become a business necessity for a multinational corporation seeking to secure market share. Although there has been much discussion on how a company gains competitive advantages through GSC management, the physical distribution of order fulfilment is less discussed in the literature. Global third-party logistics (3PL) has developed into an alternative for the needs of global distribution. In this paper, the authors present a new application of collaboration in GSC execution, namely collaborative transportation management (CTM), which can be used to reduce delivery time and improve delivery reliability. A case study is illustrated: The application of CTM by a 3PL provider in a notebook computer GSC. The implementation results show that the delivery cycle time and the total cost are simultaneously reduced.

The semiconductor properties, electronic structure and reduction susceptibility of passive films on AISI type 304 stainless steel in dilute sulphuric acid solutions have been studied by electrochemical impedance spectroscopy measurements, Mott-Schottky analysis and the photoelectrochemical technique. The passive film shows features of an amorphous or highly disordered n type semiconductor. The donor level is in the range of 1026-1027m-3and increases with the amplitude of ac potential. The passive film thickness increases linearly with the amplitude of the applied ac potential. The reduction susceptibility of the passive film is also decreased with the amplitude of the applied ac. The photoelectrochemical measurements also indicate that the passive film is n type semiconductor and the photcurrent is decreased after ac modulation. It might be related to the surface chromium accumulation.

An active resonant turn-off snubber suited for high-power IGBT converters is presented. The main feature of the snubber is that the maximum current rating of the auxiliary switching devices is small compared with that of the main switches. The basic operation of the snubber is described. This is followed by a detailed analysis of the losses in the circuit, which gives rise to an optimum snubber design procedure. An experimental version of the snubber is evaluated on an IGBT phase-arm, and detailed measurements of the efficiency of the converter are taken. The experimental results are in close agreement with the theoretical predictions.

Bone is a porous tissue that is continuously perfused by interstitial fluid. Fluid flow, driven by both vascular pressure and mechanical loading, may generate significant shear stresses through the canaliculi as well as along the bone lining at the endosteal surface. Both osteoblasts and osteocytes produce signaling factors such as prostaglandins and nitric in response to fluid shear stress (FSS); however, these humoral agents appear to have more profound affects on osteoclast activity at the endosteal surface. We hypothesized that osteoclasts and preosteoclasts may also be mechanosensitive and that osteoclast-mediated autocrine signaling may be important in bone remodeling. In this study, we investigated the effect of FSS on nitric oxide (NO), prostaglandin E2 (PGE2), and prostacyclin (PGI2) release by neonatal rat bone marrow-derived preosteoclast-like cells. These cells were tartrate-resistant acid phosphatase (TRAP) positive, weakly nonspecific esterase (NSE) positive, and capable of fusing into calcitonin-responsive, bone-resorbing, multinucleated cells. Bone marrow-derived preosteoclast-like cells exposed for 6 h to a well-defined FSS of 16 dynes/cm2 produced NO at a rate of 7.5 nmol/mg protein/h, which was 10-fold that of static controls. This response was completely abolished by 100 μM NG-amino-l-arginine (L-NAA). Flow also stimulated PGE2 production (3.9 μg/mg protein/h) and PGI2 production (220 pg/mg protein/h). L-NAA attenuated flow-induced PGE2 production by 30%, suggesting that NO may partially modulate PGE2 production. This is the first report demonstrating that marrow derived cells are sensitive to FSS and that autocrine signaling in these cells may play an important role in load-induced remodeling and signal transduction in bone.

Employing a recently derived integro-differential equation which is equivalent to the Faddeev equation, in an adiabatic approximation, we obtain accurate lower bounds to the binding energy of three-quark systems close to the upper bounds provided by the hypercentral approximation to the hyperspherical expansion method. Calculations have been performed for the Martin and the spin-dependent Ono-Schöberl potential.

BACKGROUND: Allergen exposures induce growth of airway smooth muscle in the Brown Norway rat. OBJECTIVE: The purpose of the study was to examine the role of mediators associated with the early and late responses in the induction of airway smooth muscle growth. METHODS: Nedocromil sodium was administered to block early and late responses in ovalbumin-sensitized and ovalbumin-challenged rats undergoing single or multiple challenges (5 times at 5-day intervals) with ovalbumin. Airway smooth muscle was quantitated by morphometry on lungs removed 2 days after the final challenge. RESULTS: Nedocromil sodium administered before ovalbumin challenge blocked both the early and late responses. When administered 2 hours after ovalbumin challenge, it also blocked the late response. Rats undergoing challenge with aerosolized ovalbumin five times at 5-day intervals were also treated with nedocromil before (n = 10) or 2 hours after (n = 10) each ovalbumin inhalation, respectively. The quantity of airway smooth muscle standardized for size was greater after ovalbumin challenge (0.069 +/- 0.005) compared with saline controls (0.033 +/- 0.003, p < 0.005). Nedocromil significantly reduced the airway smooth muscle (0.036 +/- 0.003, p < 0.005) when administered before ovalbumin. However, the airway smooth muscle in rats that received nedocromil 2 hours after ovalbumin challenge (0.046 +/- 0.003), although lower than in ovalbumin-challenged rats (p < 0.01), was still significantly higher than in saline-treated rats (p < 0.05). CONCLUSIONS: Allergen-induced early responses, late responses, and airway inflammation are antagonized by nedocromil. The mediators of both the early and late responses contribute to allergen-induced airway smooth muscle growth, a process that can be prevented by administration of nedocromil. (J ALLERGY CLIN IMMUNOL 1996;98:400-7.)

The potential contribution of microvascular leakage to airway narrowing during the early (ER) and late (LR) responses following allergen challenge was determined in Brown Norway (BN) rats actively sensitized with ovalbumin (OA). To study leak into the airway wall, rats (n=46) were challenged 2 weeks later with aerosolized OA, saline, or serotonin (5-HT) to study either ER (n=25), LR (n=15), or 5-HT (n=6) responses. Pulmonary resistance (RL) was used to measure airway narrowing. Microvascular leak was determined by the Evans blue (EB) technique in the airway tissues, and in another group of BN, by EB in bronchoalveolar lavage (BAL) in the airway lumen (n=43). EB increased in the airways of 5-HT challenged rats (P<0.05), but not during ER or LR. EB in BAL increased significantly during the ER (101±31.35 ng/ml BAL), vs saline challenge (10.82±1.66;P<0.05) and during the LR at 3, 4, 5, and 7 h following OA challenge compared with controls (P<0.05). These results suggest that fluid transits rapidly from the airway microvascular circulation and into the airway lumen following allergen challenge. The measurement of EB in BAL can detect microvascular leak into the airway lumen during the ER and LR. Plasma leak into the airway lumen may contribute to the increase in pulmonary resistance observed during ER and LR in BN rats.

Soluble brain extracts containing 0.1 to 16 mg of protein from 3 normal human brain and 11 patients with Alzheimer's disease, Down's syndrome and other neurological disorders were assayed for amyloid enhancing factor (AEF) activity in the mouse bioassay. At the 0.1 mg dosage, five of seven brain extracts from amyloid-positive samples and only one of four amyloid-negative samples demonstrated AEF activity. Marginal AEF activity was detected in the normal brain extracts at 8 or 16 mg protein dosage. Alzheimer-AEF was aggregated by exhaustive dialysis against 0.01 M phosphate buffer, pH 6 or distilled water and the solubilized aggregate was fractionated on a BioGel P-60 column. Of the two protein peaks, AEF activity was present only in the low mol · wt second fraction, which on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining showed two discrete and three minor peptide bands between 60 and 66 kDa and one of these was periodic acid-Schiff positive, and three fuzzy bands near 14 kDa. Pretreatment of the crude and second fraction with 10 mM phenylmethylsulfonyl fluoride (PMSF) nearly completely abolished the in vivo AEF bioactivity. It is suggested that (a) a higher AEF concentration is present in amyloid-positive brain samples than those negative for amyloid or normal brain tissues, (b) AEF-positive fraction contains at least five dominant peptides ranging between 14 to 66 kDa, and (c) abolition of PMSF-treated Alzheimer-AEF activity, similar to that of murine AEF, might be due to its serine/thiol proteinase nature. To our knowledge, this is the first time that AEF activity has been demonstrated in Alzheimer brain samples.

A polymorphic (TGCG)n, tetranucleotide repeat was discovered juxtaposed to the (GT)n dinucleotide repeat that comprises the tumor necrosis factor a microsatellite (TNF) located telomeric to the tumor necrosis factor/lymphotoxin gene cluster. The degree of complexity of this compound tetra-,dinucleotide microsatellite consists of 16 potential alleles of combined length ranging from 24 to 54 bp. The pattern of frequencies of individual alleles belonging to the compound TNFa microsatellite was established from 52 healthy volunteers and was found to be highly heterogeneous. The data diverges significantly from previously published statistics that recognized only a simple variable dinucleotide tandem repeat. The newly recognized compound tetra-, dinucleotide TNFa microsatellite polymorphism establishes a more accurate genetic basis to explore potential linkage with disease susceptibility genes located within this region of the class III major histocompatibility complex. In addition, variable tumor necrosis factor and lymphotoxin production may reflect the more complex polymorphic nature of this microsatellite region. Finally, compound microsatellites probably exist elsewhere, throughout the human genome. Recognition of their presence may have a considerable impact on the validity of past and future microsatellite-based genetic analyses.

The electrochemical impedance spectra (EIS) of iron at its corrosion potential in 0·5M H2SO4solutions, with and without addition of various concentrations of dodecylamine (DDA), were investigated. The features of the solutions with added DDA were similar to those of the blank solution, but with DDA in the presence of a 0·1 mol L−1concentration of chloride ions the EIS degenerated to a single capacitive arc with much larger transfer resistance, which corresponds to a much higher inhibition efficiency. The results of corrosion potential and polarisation measurements show that the inhibition of corrosion of iron in H2SO4solution by DDA is caused by the geometric blocking effect of the adsorbed species, irrespective of the presence of chloride. The measured EIS are consistent with a theory describing faradaic admittance at mixed potential with geometric blocking.

The detailed design procedure for the extended Luenberger observer is presented. The main features are discussed and compared with the characteristics of the extended Kalman filter which is conventionally used for joint state and parameter estimation. The extended Luenberger observer is applied in high-performance induction-motor drives with and without a speed sensor. Results from an extensive series of simulation studies are presented. These show that the extended Luenberger observer provides both rotor-flux and rotor-resistance, or rotor-flux and rotor-speed, estimates with excellent transient and steady-state performance. Experimental results verify the basic extended-Luenberger-observer algorithm.

A simplified model of the radiative decays of pseudoscalar and vector-mesons is investigated in the framework of a three-particle formalism for unstable composite particles in order to illustrate the role that unstable particles may play in providing information on the question of constituents of bosons.

The inhibition mechanism of N, N-dipropynoxymethylamine acetate on pure iron in H2SO4solution and its synergism with chloride was studied by potentiodynamic polarisation and electrochemical impedance techniques. Results showed that the inhibition mechanism was the mixed deactivation mechanism. Molecules of the inhibitor blocked the active sites on the iron surface and had a distinct inhibition synergism with chloride on the surface of the pure iron. Inhibition efficiencies and synergism were related to the concentration and molecular structure of the inhibitor.

A photoelectrochemical investigation has been carried out on an ac modulated passive film on AISI 304 stainless steel in 0·1M Na2B4O7and 0·5M Na2SO4solutions. The results of the photocurrent measurements indicate that the photoresponse is determined by defects in the electronic structure of the films when the defects lead to localised states in the band gap region and that the photoresponse is sensitive to the passive condition and testing solutions. It is concluded that the passive film on 304 stainless steel is in a highly disordered amorphous state.