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Background Renal replacement therapy (RRT) places a burden on patients, and geographical relocation for easier access to healthcare facilities is a necessity for some. Incidence and factors associated with relocation has not been comprehensively examined at a national level. We aimed to determine proportion, incidence, characteristics of RRT patients who relocate and relocation rate by remoteness of residence and dialysis modality. Methods Retrospective cohort analysis using Australian and New Zealand Dialysis and Transplant Registry to examine RRT patients in Australia from January 2005 to December 2015. Relocation incidence was calculated for remoteness of residence and RRT modality as rate per 100 patient years. Factors associated with relocation were examined using competing risk regression models with death as a competing event. Results Of 24,676 incident patients on RRT, 5888 (23.9%) relocated with a median time of 1.6 years [IQR 0.7–3.4] years. Relocation incidence was 7.9 per 100 patient years and increased from major cities to very remote regions (7.2 to 48.8 per 100 patient years respectively, p p = 0.034) and very remote regions (SHR 3.51 95% 3.05, 4.04 p p = 0.002) while transplant patients were less likely to relocate compared to haemodialysis patients (HR 0.37, 95%CI 0.34, 0.39, p Conclusions Relocation in patients receiving RRT is associated with remoteness of residence, RRT modality and ethnicity. Reasons for relocation and its impact on patient wellbeing and outcome should be further explored.

Usher syndrome type III (USH3), characterized by progressive deafness, variable balance disorder and blindness, is caused by destabilizing mutations in the gene encoding the clarin-1 (CLRN1) protein. Here we report a new strategy to mitigate hearing loss associated with a common USH3 mutation CLRN1(N48K) that involves cell-based high-throughput screening of small molecules capable of stabilizing CLRN1(N48K), followed by a secondary screening to eliminate general proteasome inhibitors, and finally an iterative process to optimize structure-activity relationships. This resulted in the identification of BioFocus 844 (BF844). To test the efficacy of BF844, we developed a mouse model that mimicked the progressive hearing loss associated with USH3. BF844 effectively attenuated progressive hearing loss and prevented deafness in this model. Because the CLRN1(N48K) mutation causes both hearing and vision loss, BF844 could in principle prevent both sensory deficiencies in patients with USH3. Moreover, the strategy described here could help identify drugs for other protein-destabilizing monogenic disorders.

Experimental, controlled, animal study. To assess the effects of vitamins C and E (VCE) treatment on oxidative stress and programmed cell deaths after rat spinal cord injury (SCI), as well as functional recovery. Taiwan. Fifty-four Sprague–Dawley rats were used for the experimental procedure. In the sham group, laminectomy at T10 was performed, followed by impactor contusion of the spinal cord. In the control group, only a laminectomy was performed without contusion. Oxidative stress status was assessed by measuring the spinal cord tissue content of superoxide dismutase (SOD) and gluthatione peroxidase (GSH-Px) activities. We also evaluated the effects of combined VCE treatment using western blot to analyze expression of cleaved caspase-3 and microtubule-associated protein light chain 3 (LC3), and the Basso, Beattie and Bresnahan (BBB) scale to evaluate functional outcomes. Combined treatment of VCE significantly counteracted the effects of spinal cord contusion on oxidative stress represented by activities of SOD and GSH-Px (P

Background Medication non-adherence is common among renal dialysis patients. High degrees of non-adherence in randomized controlled trials (RCTs) can lead to failure to detect a true treatment effect. Cardio-protective pharmacological interventions have shown no consistent benefit in RCTs involving dialysis patients. Whether non-adherence contributes to this lack of efficacy is unknown. We aimed to investigate how medication adherence and drug discontinuation were assessed, reported and addressed in RCTs, evaluating cardiovascular or mortality outcomes in dialysis patients. Methods Electronic database searches were performed in MEDLINE, EMBASE & Cochrane CENTRAL for RCTs published between 2005–2015, evaluating self-administered medications, in adult dialysis patients, which reported clinical cardiovascular or mortality endpoints, as primary or secondary outcomes. Study characteristics, outcomes, methods of measuring and reporting adherence, and data on study drug discontinuation were analyzed. Results Of the 642 RCTs in dialysis patients, 22 trials (12 placebo controlled), which included 19,322 patients, were eligible. The trialed pharmacological interventions included anti-hypertensives, phosphate binders, lipid-lowering therapy, cardio-vascular medications, homocysteine lowering therapy, fish oil and calcimimetics. Medication adherence was reported in five trials with a mean of 81% (range: 65–92%) in the intervention arm and 84.5% (range: 82–87%) in the control arm. All the trials that reported adherence yielded negative study outcomes for the intervention. Study-drug discontinuation was reported in 21 trials (mean 33.2%; 95% CI, 22.0 to 44.5, in intervention and 28.8%; 95% CI, 16.8 to 40.8, in control). Trials with more than 20% study drug discontinuation, more often yielded negative study outcomes (p = 0.018). Non-adherence was included as a contributor to drug discontinuation in some studies, but the causes of discontinuation were not reported consistently between studies, and non-adherence was listed under different categories, thereby potentiating the misclassification of adherence. Conclusions Reporting of medication adherence and study-drug discontinuation in RCTs investigating cardiovascular or mortality endpoints in dialysis patients are inconsistent, making it difficult to compare studies and evaluate their impact on outcomes. Recommendations for consistent reporting of non-adherence and causes of drug discontinuation in RCTs will therefore help to assess their impact on clinical outcomes. Electronic supplementary material The online version of this article (doi:10.1186/s12882-017-0449-1) contains supplementary material, which is available to authorized users.

Gender-specific determinants of blood pressure (BP) values and control have not been the focus of clinical hypertension research. The purpose of this analysis was to identify gender-specific and multi-level (physician and patient) determinants of BP values and predictors of uncontrolled BP. We completed a subgroup analysis comparing men and women who participated in the Belgian PREVIEW study of second-line treatment effectiveness of valsartan, applying two-level hierarchical modelling of 90-day BP values and guideline-defined BP control. In total, 1665 women and 1525 men were treated by 504 general practitioners. Fewer women than men reached systolic BP (SBP) (P=0.015) and combined BP targets at 90 days (P=0.007). More than 26% of the variance in 90-day SBP (intra-class correlation coefficient (ICC)=0.270) and diastolic BP (DBP) (ICC=0.262) was attributable to physician-level factors for men; the physician-level ICCs for SBP and DBP were 0.259 and 0.268, respectively, for women. Determinants of 90-day BP values and predictors of uncontrolled BP varied considerably by gender. Many of the multi-level determinants of BP by gender are amenable to intervention, and the remainder can serve as warning signs to clinicians that patients may remain vulnerable to poor outcomes associated with sub-optimal BP control.

The effects of Sc2O3 on the properties of (Co, Nb)-doped SnO2 varistors were investigated. It was found that by characterizing the samples, sintered at 1300 °C, the nonlinear coefficient presents a peak of α=28.6 for a concentration of 0.05 mol % Sc2O3. The average grain size decreases from 2.9 μm to 1.5 μm, and the breakdown electrical field increases from 655 V/mm to 2197 V/mm. The relative electrical permittivity decreases from 7574 to 792 on increasing Sc2O3 from 0.05 mol % to 0.08 mol %. The increase of the breakdown electrical field with increasing Sc2O3 concentration is mainly attributed to the decrease of the grain size. The reason why the permittivity decreases with increasing Sc2O3 concentration originates from the ratio of the grain size to the barrier width. To illustrate the grain-boundary barrier formation of (Sc, Co, Nb) doped SnO2 varistors, a modified defect barrier model was introduced, in which the negatively charged acceptors substituting for Sn ions should not be located at the grain interfaces, but at SnO2 lattice sites of depletion layers instead.

The relationships between inflammation in organs with Toxocara canis larval migration and matrix metalloproteinase-9 (MMP-9) were investigated following the infection of mice with 1,000 infective eggs. Gelatinase activity was defined by gelatin zymography, optimum pH, inhibitor specificity and Western blot analysis. MMP-9 activity was present in the lungs, liver, muscles, and brain during T. canis larval migration. This enzyme had a molecular weight of about 94 kDa and showed maximum activity in the pH range of 6-8. The increased MMP-9 proteinases coincided with larval recovery and the degree of inflammation among the four organs. These results suggest that MMP-9 may be associated with the inflammatory reaction to larval toxocariasis during early migration, and may therefore be a useful marker during T. canis larvae migration.

The effects of the addition of lead on the morphology, microstructure and capacitance of etched aluminum foils for high voltage electrolytic capacitors are investigated here. The results show that the etched tunnels had square cross sections about 1.3 μm per side. The inner tunnel sidewalls had a rough corrugated texture with regular ripples with a periodic interval of about 0.12 μm. The addition of lead to high purity aluminum foils can effectively increase the number of grains and etched holes, which enhances the etching of the surface. However, the cubic textured fraction will be reduced. The experiments showed that the maximum capacitance was obtained when the incremental addition of lead reached 0.3 ppm.

A 49-year-old drunken man was involved in a motorbike crash. He presented with cervical spine injury and multiple limbs fracture. Neuro-imaging demonstrated disruption of the C5-6 anterior longitudinal ligament, herniation of C3-4 and C5-6 discs, and Th1 compression fracture. The neurological deficits improved after anterior cervical decompression, fusion and fixation. One week later, he suffered from fever and severe upper back pain, and he developed paraplegia subsequently. The following image study disclosed esophageal perforation at the level of Th1 and epidural abscess spreading from levels Th1 to Th5. After proper management and rehabilitation, he achieved good recovery one year later at follow-up. We report the unique case of Th1 fracture with esophageal perforation complicated with spinal epidural abscess. The possible mechanism and the controversy concerning therapy for esophageal perforation are discussed.

The effects of the addition of silver content and stabilizing treatment on etching morphology, microstructure and static capacity were investigated for aluminum foils of an electrolytic capacitor. It was found that silver content in foils promoted Al–Fe–Mn and Al–Fe–Mn–Si precipitation as well as enhanced surface etching. The static capacity increased with increasing of silver content up to 0.2% and then decreased. Also, the stabilizing treatment enhanced re-crystallization so as to increase the static capacity of the cathode foil.

Various C\D wafers (Control and Dummy wafers) are used in wafer fabrication to enhance product quality and process stability. Most wafer fabs downgrade used C\D wafers into other functional ones and then recycle them to reduce costs. Wafer costs increase with wafer diameter, and thus the downgrading mechanisms and inventory control of C\D wafers have become increasingly important to fab performance. Wafer fabs now are willing to seriously consider C\D wafer management but C\D wafer management remains neglected in the literature. This study presents a novel pull system focusing on inventory and downgrading management of C\D wafers. The proposed system in this study intends to reduce the WIP level of C\D wafers, increase recycled usages (number of times C\D-wafer lots are recycled) before scraping, and reduce machine delay ratio without lowering the product wafer throughput rate.

Microstructures of radio frequency (RF) and direct current (DC) plasma-sprayed Al2O3 coatings deposited onto steel substrates were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), electron microprobe analysis (EMPA), polarizing optical microscopy (OM), and transmission electron microscopy (TEM). Because RF and DC plasmas produce different particle heating and acceleration, the morphology, phase structure, and fracture modes of the coatings vary substantially. In the case of RF coatings, a clear lamellar microstructure with relatively thick lamellae was observed, which is due to the large particles and the low particle velocities, with α-Al2O3 as the predominant phase and with delamination type of fracture detected on the fracture surface. In contrast, the DC coatings consisted of predominantly metastable γ-Al2O3 as well as amorphous phases, with a mixed fracture mode of the coating observed. In spite of limited interfacial interdiffusion detected by EMPA, TEM showed an interfacial layer existing at the interface between the coating and the substrate for both cases. For RF coatings, the interfacial layer on the order of 1 µm was composed of three sublayers, each of which was different in composition and morphology. However, the interfacial layer for the DC coating consisted primarily of an amorphous phase, containing both coating and substrate materials with or without platelike microcrystals; although in some regions a thick amorphous Al2O3 layer was in direct contact with the substrate.

Aims/hypothesis. Several investigations have shown that the renal medulla has a greater capacity to generate nitric oxide than the renal cortex. To further evaluate the changes of nitric oxide synthesis in the kidney, particularly in the outer medulla, in disorders involving fluid and electrolyte imbalances, we sought to determine renal nitric oxide synthase expression in the diabetic rats. Methods. We determined renal nitric oxide synthase mRNA and urinary nitrite/nitrate excretion in 12 normal and 12 streptozotocin-induced diabetic rats by reverse transcription-polymerase chain reaction with Southern blot hybridization and with Griess reaction, respectively. Nitric oxide synthase immunoreactivity was detected by immunohistochemistry in four normal and four diabetic rats. Results. Neuronal and endothelial nitric oxide synthase mRNA were 3.5-fold and 1.8-fold increased in the outer medulla of 12 diabetic rats with no difference found in the cortex and inner medulla when compared with 12 normal rats. Urinary nitrite/nitrate excretion was significantly increased from the first week after diabetic induction. In normal rats, immunohistochemical studies showed positive neuronal and endothelial nitric oxide synthase immunostaining in almost all segments of renal tubules. Diabetic rats had the greatest enhancement of immunostaining for neuronal and endothelial nitric oxide synthase in the proximal straight tubule and medullary thick ascending limb. Conclusion/interpretation. Our results indicate that increases in neuronal and endothelial nitric oxide synthase synthesis in the kidney, particularly in the outer medulla, possibly play an important part in the adaptation of renal function to hyperglycaemia and hyperosmolality in diabetes. [Diabetologia (2000) 43: 649–659]

Most previous studies have shown that the digestive tract of the neonate is rapidly and heavily colonized in the first few days of life, but all the studies so far used either feces or rectal swabs to isolate and identify bacterial colonization. The exact timing of intestinal colonization is not yet certain. From a retrospective analysis of 24 neonates with intestinal perforation and a prospective study of 30 ill neonates aged less than 10 days who recieved intestinal-tract operations, we found that the incidence of bacterial growth from small-and large-bowel specimens was significantly lower within 48 h after birth and the intestinal tract was almost completely sterile within 24 h after delivery. Most of the bacteria were aerobic gram-negative bacilli, and the most common species was Escherichia coli. Although our results may not represent conditions in the normal neonate, knowledge of bowel colonization in such patients will be helpful for further management.

” Springer-Verlag 1998 Summary The aim of the study was to compare the sensitivity of short-wavelength and conventional automated static threshold perimetry for the psychophysical detection of abnormality in patients with clinically significant diabetic macular oedema. The sample comprised 24 patients with clinically significant diabetic macular oedema (mean age 59.75 years, range 45‐75 years). One eye of each patient was selected. Exclusion criteria included the presence of lenticular opacity. The sensitivity of the macular visual field of each patient was determined with programme 10‐2 of the Humphrey Field Analyser on two occasions, using both short-wavelength and conventional stimulus parameters; the results of the second session were analysed to minimise learning effects. A pointwise horizontal hemifield asymmetry analysis was derived for short-wavelength perimetry (thereby negating the influence of pre-receptoral absorption); the pointwise pattern deviation probability plot was analysed for conventional perimetry. Abnormality was defined as 3 or more contiguous stimulus locations with negative asymmetries (short-wavelength) or reduced sensitivity values (conventional) that resulted in a statistical probability level of p less than 0.05. The fields of 8 patients were abnormal as assessed by conventional perimetry while all were classified as abnormal using short-wavelength perimetry. In the 8 patients who exhibited both abnormal conventional and abnormal short-wavelength perimetry results, the extent of field loss was generally greater using short-wavelength perimetry. The position of the localised field loss (i. e. as distinct from field loss that was generalised across the visual field) assessed by short-wavelength perimetry corresponded with the clinical mapping of the area of diabetic macular oedema but the extent of this loss was generally greater than that suggested by clinical assessment. Short-wavelength automated perimetry offers improved sensitivity for the psychophysical detection of clinically significant diabetic macular oedema. [Diabetologia (1998) 41: 918‐928]

The size effects due to changes in gauge length and the influence of the fragmentation phenomenon in fibrous structures are examined. First, a theoretical analysis of the differences of the size effects in single fibre and in a fibrous structure is conducted. Then comprehensive experimental work is presented on single fibres, fibre bundles, and twisted yarns which can be considered as pseudo-composites. Next a comparison is made between the theoretical predictions and the experimental data. Causes for the size effect in a fibrous structure are explored. © 1998 Chapman & Hall

A commercial torch has been modified to introduce an additional anti-vortex and shroud gas flow to counter the detrimental effects brought about by the vortex plasma gas flow which is used to stabilize the cathode arc attachment and to increase the anode life. Deposition efficiency and coating quality are used as criteria to judge the modified versus the nonmodified torch. High-speed videography and computerized image analysis systems are used to determine the particle trajectories, velocities, and the plasma jet geometry. The results show that the additional anti-vortex and shroud gas flow to the torch can keep the particles closer to the torch axis and reduce the amount of entrainment of cold air into the plasma jet. The consequence is that deposition efficiency and coating quality are substantially improved.

The size of a fibre affects its mechanical properties and thus is of theoretical and practical importance for studies of the rupturing process during loading of a fibrous structure. This paper investigates the overall effects of length on the mechanical behaviour of single fibres. Four types of fibres, ranging from brittle to highly extensible, were tested for their tensile properties at several different gauge lengths. Different from most previous studies where the focus has been on the gauge length effects on a single property such as fibre strength or breaking strain, this paper look comprehensively into the effects of length on all three of the most commonly studied mechanical properties, namely strength, breaking strain and initial modulus. Particular emphasis is placed on initial modulus and on the interactions between all three parameters. Influences of strain rate and fibre type on the size effects are also investigated. The effect of potential fibre slippage on experimental error is examined. An image analysis method is used to measure the real fibre elongation in comparison to the same fibre elongation obtained directly from an Instron tester. Finally, a statistical analysis is carried out using the experimental data to test the fitness of the Weibull theory to polymeric fibres. This was done as the Weibull model has been extensively utilized in examining fibre strength and breaking strain, although it is supposed to be valid only for the so-called classic fibres to which more extensible polymeric fibres do not belong.

The temporal retina is larger than the nasal retina and contains the metabolically active fovea. The variation in the distribution of blood between the temporal and nasal retinal circulations was investigated in 15 healthy volunteers, and the autoregulatory capacity of the temporal and nasal circulations was quantitated using 60% oxygen in the inspired air. Retinal blood flow was determined from red cell velocity using laser Doppler velocimetry and retinal vessel diameter from retinal photographs using a digital image analysis system. Volume flow was lower in the nasal than the temporal circulation by 52.49% (p < 0.001). This is a consequence of both significantly smaller vessels (20.4%, p < 0.001) and slower blood velocity in the nasal circulation (24.64%, p = 0.003) compared with the temporal vessels. After breathing 60% oxygen for 10 minutes, there was significant vasoconstriction (temporal, 10.42 +/- 1.24%, p < 0.001; nasal, 7.66 +/- 1.48%, p < 0.001), slower red cell velocity (temporal, 27.10 +/- 3.92%, p < 0.001; nasal, 27.36 +/- 5.51%, p < 0.001) and a significant reduction in the volumetric flow rate (temporal, 41.16 +/- 3.64%, p < 0.001; nasal, 37.99 +/- 5.07%, p < 0.001). The reduction in the haemodynamic parameters was comparable in the temporal and nasal circulations, indicating similar autoregulatory capacity. Retinal vascular conductance was calculated from volume flow and retinal perfusion pressure. It was 53% larger in the temporal than the nasal circulations. This provides an index of the metabolic needs of the different regions of the retina.

Semiconducting ceramics are widely used in electrical industries involving mobile communications, computers, signal processing, power transport, and control systems, because of their unique and useful electrical characteristics [1]. Varistors which are generally used to protect electronic circuits from voltage shock can sense and limit high transient voltage surges and can repeatedly endure such surges without being destroyed. The most important property of a varistor is its nonlinear voltage–current characteristic. It can be expressed by the equation I = K V α . The α coefficient gives the degree of nonlinearity and the constant K depends on the microstructure and is related to the electrical resistivity of the material. Commercial varistors used in protection systems are based on SiC or on ZnO. Varistors based on SiC have low nonlinearity coefficients [2–4] and ZnO varistors exhibit high nonlinear coefficients, but the degradation problem of ZnO varistors has not been resolved [5–7]. Therefore, the efforts to find new varistor materials have been ongoing. In 1983, N. Yumaka, M. Masuyama found that SrTiO3-based ceramics made by a two-step process had varistor characteristics [8]. In 1995, S. A. Pianaro found a new varistor material [4], (Co,Nb)-doped SnO2, which has only a single phase, rutile structure. In 2000, J. F. Wang found one oxide (Sb2O3)-doped TiO2 ceramic to have varistor behavior [9]. Following Wang, W. B. Su found, in 2002, another TiO2 varistor doped with only one oxide (WO3) [10]. In this work, we found a new varistor material, (Nb,Si)-doped ZnSnO3, and investigated the effects of SiO2 on the properties of the (Nb,Si)-doped ZnSnO3 varistor. The materials used were analytical grades of SnO2 (99.5%), Nb2O5 (99.5%), ZnO (99.5%), and SiO2 (90.0%). The compositions were SnO2 + ZnO + 0.2%Nb2O5 + x%SiO2 in molar terms, where x = 0, 0.25, 0.4, 0.5, 1.0. The varistors were prepared by conventional ceramic processing. The mixed raw chemicals were milled in a nylon kettle with ZrO2 balls and some distilled water, dried, mixed with 0.6% weight of PVA binder and pressed into disks 15 mm in diameter and 1.5 mm in thickness at 160 MPa. The disks were sintered at 1427 ◦C for an hour and cooled to room temperature after burning out the PVA binder at 650 ◦C. To measure the electrical properties, silver electrodes were made on both surfaces of the sintered disks. For microstructure characterization, the surfaces of the samples were observed by scanning electron microscopy (SEM) and the phases were analyzed by X-ray diffraction (XRD). For electrical characterization of current density versus applied electrical field, an I–V grapher (QT2) was used. The complex impedance dependent on frequency is measured using an Agilent 4294A impedance analyzer. According to the XRD analysis (Fig. 1), no apparent second phase was observed and SnO2 and ZnO should be synthesized according to the following reaction [11]

The structure of controlled high-strain-rate shear bands generated in heterogeneous reactive porous materials (Nb + Si, Mo + Si + MoSi2) has been investigated using axially symmetric experimental configurations in which the source of energy is the detonation of low velocity explosives. The deformation was highly localized, with profuse formation of shear bands, which have thicknesses of 5 to 20 μm. The experimental method generated overall strains up to 100 and strain rates\(\dot \gamma \) of approximately 107 s-1. Changes in particle morphology, melting, and regions of partial reaction on three different length scales were observed. The shear band thickness is smaller than the initial characteristic particle size of the porous mixture (≤44 μm), ensuring a cooling time of the deformed material on the same order of magnitude as the deformation time (10-5 s). In the shear localization regions, two characteristic phenomena were observed: (a) a shear fracture subdividing the Nb particles into thin parallel layers and (b) the formation of vortices. A mechanism for the reaction inside the shear bands is proposed, and an expression for the largest size of chemical products as a function of shear deformation is obtained.

This study investigated the effect of betaxolol, a beta 1 selective blocker, on the retinal circulation in 10 patients with ocular hypertension. In a masked randomised fashion, one eye of each subject received betaxolol and the fellow eye received placebo (hypromellose). Retinal blood flow (RBF) was determined in a major temporal vein of each eye just prior to instillation of drops and 2 h later, using laser Doppler velocimetry and monochromatic fundus photography. There was an increase of 15.0% in RBF (p = 0.03) in the betaxolol-treated eyes. No significant change was observed in the placebo-treated eyes. Intraocular pressure was reduced by 27.7% in the treated eyes, resulting in an increase of 16.9% in perfusion pressure (p = 0.02) compared with an 8.4% increase in placebo-treated eyes (p = 0.15). This study demonstrated that betaxolol increases RBF in eyes with ocular hypertension; this increase is probably related to the increase in perfusion pressure.

Non-aseptic fermentation of a 28 brix cane molasses solution was successfully carried out in a pilot-scale 5-stage multi-feeding continuous system for 30 days. The effluent ethanol concentration, overall volumetric productivity and sugar conversion yield averaged 8.54 % (v/v), 5.35 g/L-hr and 92.4 % of theoretical, respectively.

Varistors can limit high transient voltage surges and can repeatedly endure such surges without being destroyed, therefore they are usually used to protect electronic circuits from voltage pulse shocks. The most important property of a varistor is its nonlinear voltage–current characteristic. This can be expressed by the equation I = K V α , where α is the coefficient of non-linearity, the essential parameter to scale the nonlinearity. Commercial varistors used in protection systems are based on SiC or ZnO. Varistors based on SiC have low coefficients (of non-linearity) [1]. ZnO varistors exhibit high coefficients (of nonlinearity), but the degradation problem of ZnO varistors has not been resolved [2, 3]. While efforts to improve the temperature stability of ZnO varistors are being made, the search for new varistor materials is ongoing. In 1995, Pianaro found a new varistor material, (Co, Nb)-doped SnO2, which is single phase with the rutile structure [1]. In 1999, Kim et al. found a one-step-air-fired SrTiO3-based ceramic which had varistor characteristics [4]. In 2000, Wang found that only one oxide (Sb2O3)-doped TiO2 ceramics shows varistor behavior [5]. Following Wang, in 2002, Su found another TiO2 varistor, doped with only one oxide (WO3) [6]. In this letter, the processing of a new WO3-based varistor system, WO3·Na2CO3·CuO/CdO/Bi2O3/ Sb2O3, as well as its nonlinear properties (electrical field as a function of current density) and dielectric properties are described. The raw chemicals used in this study were analytical grades of WO3 (99%), Na2CO3 (99.8%), CuO (98%), CdO (99%), Bi2O3 (99%), Sb2O3 (99.9%) and obtained from Shanghai Chemical Company. The composites investigated in the present work contain a molar ratio of WO3:Na2CO3:X = 96.5:0.5:3, where X = CuO, CdO and WO3:Na2CO3:Y = 98:0.5:1.5, where Y = Bi2O3, Sb2O3. Varistors were obtained by conventional ceramic processing. The mixed raw chemicals were milled in nylon pot for 15 h with ZrO2 balls and some distilled water, dried, mixed with 0.5 wt% PVA binder and pressed into disks 15 mm in diameter and 1.5 mm in thickness at 180 MPa. After burning out the PVA binder at 650 ◦C, the disks were sintered in air at 1000 ◦C for 60 min and then slowly cooled to room temperature. During sintering, compacts were surrounded with powders of matching compositions and covered with crucibles to reduce evaporation. The frequency dependence of the relative dielectric constant and complex impedance spectra were obtained using an impedance analyzer (Agilent 4294A). For electrical characterization of current density as a function of applied electrical field, a semiconductor I–V grapher (QT2) was used. The coefficient of non-linearity α was obtained from

For light-emitting porous Si there has been a severe problem with instability and degradation of the light emission. We report that a stabilization of the emission intensity and the peak energy can be achieved in air by a proper laser irradiation, In-situ photoluminescence measurements were performed to monitor the degradation and stabilization process under different conditions and parameters, such as laser power, laser wavelength and environment (ambient atmosphere of certain gas or ultra high vacuum). We found oxygen is the major cause for the emission degradation in this laser enhanced adsorption process, and the laser heating effect can be excluded. For a comparison we study the reversible thermal heating and quenching process. We also discuss microwave and ECR plasma passivation results.

The effect of the oxygen supply pattern on the onset and development of the lignolytic enzyme system of Phanerochaete chrysosporium was studied in submerged culture employing the serum bottle approach. Periodic or continuous flushing through the head phase, and continuous bubbling through the liquid phase with either oxygen (O2) or air were applied. The nature of the O2 supply had a crucial regulatory effect not only on the formation of lignin-degrading peroxidases but also on their decay and on the production of extracellular protease activity and polysaccharides. Continuous oxygenation or aeration increased the glucose consumption rate, extracellular protease activity and polysaccharides. Gassing with air, whether continuous or periodic, sustained Mn-peroxidase activity while ligninase was undetectable. Continuous O2 supply speeded up ligninase decay, displaying a sharper maximum, while a broader maximum and slower decay of ligninase activity were observed when supplying periodic O2. Cultures initially grown with free exposure to air displayed a higher but sharper ligninase activity maximum when shifted to continuous rather than periodic O2 supply. In general, the higher levels of either polysaccharides or protease activity corresponded to the lower levels and faster decay of ligninase and Mn-peroxidase activities.

The results of an investigation into the possibility of growing YBa2Cu3O7 (or Y123) single crystals from a NaCl-KCl flux (salt flux) are presented. They are compared with results for Y123 crystals grown from a Ba-Cu-oxide flux system. The chosen salt flux composition was 1:1 (NaCl:KCl). The preparation method of the solutes is presented, with particular attention given to the compounds surrounding the Y123 phase, such as Y2BaCuO6 (Y211). Optical microscopy was introduced to study the morphology of the sample; X-ray diffraction was used for phase identification; and a chemical analysis was effected. The Y123, Y211, and BaCuO2 phases were shown to be dissociated in the NaCl-KCl flux, and could not be recrystallized. A small amount of the flux could be added to create large-grain Y123 crystals, but single-crystal growth was not possible in a top-seeded NaCl-KCl solution. This is attributed to significant differences in solubility of the crystal elements, and phase separation caused by CuO crystal formation.

In 60 patients with cardiac symptoms and anxiety, the anxiolytic effect of the ancient Chinese remedy Suanzaorentang has been studied. It was a promising anxiolytic remedy, without apparent adverse effects on the cardiovascular system, and appearing not to interact with other drugs.

The effect of phosphorus and silicon on the formation of retained austenite has been investigated in a low-carbon steel cold rolled, intercritically annealed, and isothermally held in a temperature range of bainitic transformation followed by air cooling. The steel sheet containing phosphorus after final heat-treatment consisted of ferrite, retained austenite, and bainite or martensite. Phosphorus, especially in the presence of silicon, in steel was useful to assist the formation of retained austenite. Mechanical properties, such as tensile strength, uniform elongation, and the combination of tensile strength/ductility, were improved when phosphorus was increased up to 0.07 pct in 0.5 pct Si steel. This could be attributed to the strain-induced transformation of retained austenite during tensile deformation. Furthermore, two types of retained austenite were observed in P-containing steel. One is larger than about 1 μm in size and usually exists adjacent to bainite; the other one is of submicron size and usually exists in a ferrite matrix. High phosphorus content promotes the formation of stable (small size) austenites which are considered to be stabilized mainly by their small size effect and have a different formation mechanism from the coarser retained austenite in the lower P steels. The retained austenites of submicron size showed mechanical stability even after 10 pct deformation, suggesting that these small austenites have little effect on ductility. The 0.07 pct P-0.5 pct Si-1.5 pct Mn-0.12 pct C steel showed a high strength of 730 MPa and a total elongation of 36 pct.

Aberrant differentiation is a frequent hallmark of tumors, suggesting that modulators for differentiation and proliferation play a role in multistage carcinogenesis and that their use can also be exploited in cancer chemoprevention and therapy. We have demonstrated that selenium (Se) may be a modulator for the differentiation and proliferation of tumor cells. Evidence has been obtained that Se exerts the following effects: reversing changes of biochemical phenotypes toward normal levels, including reduction of cGMP level and cAMP-dependent protein kinase isozyme type I; increase in cAMP level and cAMP-dependent protein kinase isozyme type II, and altering membrane properties. Furthermore, we have obtained support for this hypothesis utilizing experiments on cultured human liver cell lines. It is demonstrated that Se can lead to the following changes: a. reduction of mitotic index; b. increase in the adhesiveness of cells; c. decrease in confluent saturation density and induction of an early contact inhibition; and d. decrease in tumorigenicity. For the purpose of comparison, the effects of Se on the normal counterparts was also studied. Contrary to what was observed above, there was no significant change in both biochemical and cellular aspects of normal cells treated analogously.

Experiments were conducted with Zymomonas mobilis in an attached film expanded bed (AFEB) fermentor at different dilution rates, using a feed glucose concentration of 100 gm/l. Vermiculite was used as the bed material for attachment of the bacterial film. Ethanol volumetric productivities were maximum at a dilution rate of 3.6hr-1. The productivities were 105 gm/l-hr and 210 gm/l-hr based on total fermentor volume and bed volume, respectively.

Variations with regard to heat tolerance, in terms of heading ability, and water consumption under high temperatures were studied in various Chinese cabbage (Brassica campestris spp. pekinensis Rupr.) varieties. Total water consumption did not differ among entries; however, heat tolerant varieties had greater water uptake than heat sensitive ones at the onset of head formation. Heat tolerant varieties also possessed thicker leaves, higher leaf sap electrical conductivity and chlorophyll content, and lower stomatal number. These characteristics appeared to facilitate water transport to the leaves and reduce transpiration, thus enabling the heat tolerant plants to maintain leaf turgidity during the heading stage at high temperature. Vigorous root growth also seems essential to supply adequate water to the leaves so that they can maintain good turgor at high temperature. Breeding for heat tolerance in Chinese cabbage may be accomplished indirectly by selecting for plants which possess relative thick leaves, high levels of electrolytes, high chlorophyll content, few stomata, and vigorous root growth.

The electromagnetic waves and plasma oscillations excited by a magnetic current ring source around an infinitely long compressible plasma column are studied. The governing partial differential equations for the electromagnetic and plasma modes are first formulated. They are then converted to ordinary differential equations by means of the Fourier transformation. The fields outside the plasma column are composed of a surface wave part contributed by the poles on the path of integration and a radiated part arising from branch points. The far zone radiation field is evaluated by the method of steepest descent through a saddle point. The presence of the plasma column modifies the radiated electromagnetic field of the ring source, and the radiation pattern depends on the plasma parameters in a complicated way.

The effect of the group V isoelectronic dopant antimony (Sb) on the optimum growth temperature for GaAs and AIGaAs MBE grown films is examined with the aim of producing heterostructures at the lowest possible temperatures. RHEED intensity oscillations have been used to quantify the incorporation rate of Ga, Al, and As for different growth temperatures. The electrical properties of the layers are characterized using photoluminescence spectroscopy (PL), Hall mobility measurements, and deep level transient spectroscopy (DLTS). Results show that isoelectronic Sb doping of GaAs and AIGaAs permits the growth of these materials at temperatures up to 800C lower than optimum, with deep level trap densities, photoluminescence quality, and Hall mobilities at least comparable or better than those films grown at optimal temperatures.