The susceptibility of the kidneys to fluoride toxicity can largely be attributed to its anatomy and function. As the filtrate moves along the complex tubular structure of each nephron, it is ...concentrated in the proximal and distal tubules and collecting duct. It has been frequently observed that the children suffering from renal impairments also have some symptoms of dental and skeletal fluorosis. The findings suggest that fluoride somehow interferes with renal anatomy and physiology, which may lead to renal pathogenesis. The aim of this study was to evaluate the fluoride-associated nephrotoxicity. A total of 156 patients with childhood nephrotic syndrome were screened and it was observed that 32 of them had significantly high levels (p ≤ 0.05) of fluoride in urine (4.01 ± 1.83 ppm) and serum (0.1 ± 0.013 ppm). On the basis of urinary fluoride concentration, patients were divided into two groups, namely group 1 (G-1) (n = 32) containing normal urine fluoride (0.61 ± 0.17 ppm) and group 2 (G-2) (n = 32) having high urine fluoride concentration (4.01 ± 1.83 ppm). Age-matched healthy subjects (n = 33) having normal levels of urinary fluoride (0.56 ± 0.15 ppm) were included in the study as control (group 0 (G-0)). Kidney biopsies were taken from G-1 and G-2 only, who were subjected to ultrastructural (transmission electron microscopy) and apoptotic (terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling) analysis. Various subcellular ultrastructural changes including nuclear disintegration, chromosome condensation, cytoplasmic ground substance lysis, and endoplasmic reticulum blebbing were observed. Increased levels of apoptosis were observed in high fluoride group (G-2) compared to normal fluoride group (G-1). Various degrees of fluoride-associated damages to the architecture of tubular epithelia, such as cell swelling and lysis, cytoplasmic vacuolation, nuclear condensation, apoptosis, and necrosis, were observed.
Trust and control are inextricably interlinked with risk in strategic alliances. Hence, to understand how partner firms can effectively reduce and manage this risk, we need to examine the ...inter-relationships between trust, control, and risk. In this article, we propose a comprehensive and integrated framework of the three constructs in the context of strategic alliances, contending that trust and control are the two principal antecedents of risk. First, we suggest that the three constructs are each comprised of certain key dimensions. Risk can be considered separately as relational risk and performance risk. The two dimensions of trust are identified as goodwill trust and competence trust, and control is differentiated in terms of the three modes of behaviour control, output control, and social control. Second, we discuss systematically the various linkages between the different types of trust, control, and risk in alliances. Third, we suggest several risk reduction approaches — minimizing relational risk through goodwill trust, behaviour control, and social control, while minimizing performance risk through competence trust, output control, and social control. Fourth, we discuss a number of trust-building techniques and control mechanisms to reduce risk in different types of strategic alliances. Finally, we develop propositions for empirical testing of the integrated framework and offer brief comments on future research directions and managerial implications
The investigation addresses the impact of stress on soft magnetic and giant magneto-impedance (GMI) of rapidly quenched Fe77.5Si7.5B15, (Co94Fe6)72.5Si12.5B15 and (Co94Fe6)72.5Si12.5B12.5Nb0.5Cr2 ...microwires. Differential scanning calorimetry revealed interesting phase stability in the later alloys. The vitrified microwires contained dominant Co and a lean Fe content showed much superior soft magnetic properties and high magnetoimpedance. The alloy microwires incorporated with Nb and Cr manifested lowest coercivity value of 0.034 Oe with a high GMImax value of 425% in the as-quenched state. The uniaxial stress applied on the microwires modified the shape of the hysteresis loops and GMI plots. The hysteresis loops showed stress dependence of coercivity based on alloy chemistry, phase stability and consequent magnetostriction. The GMImax revealed sensitive change with respect to the applied stress in all the alloy microwires. In addition to GMImax interesting features were observed in the GMI profile pertaining influence of stress on the anisotropy field. The anisotropy field shifted systematically in one of the alloy microwires which displayed symmetric dual GMI peaks. The stress was also found to modify the asymmetric characteristics in a microwire.
•The magnetic hysteresis properties are affected by uniaxial tensile stress.•The shape of the GMI plot is modified by applied stress.•Anisotropy field in specific microwires modified with stress intensity.•Stress phenomena discussed on basis of magnetostriction and as-quenched state.
Trust and risk have often been linked in the literature, but their relationship is far from clear. Trust has been used in three different ways - namely, as a perception ("subjective trust"), as ...various personal and situational factors that lead to subjective trust ("trust antecedents"), and as the actions resulting from subjective trust ("behavioral trust"). We explain how risk is related to these three conceptions of trust. First, we argue that subjective trust and perceived risk are in fact mirror images of each other. Second, we show how behavioral trust can be viewed as risk taking, so that the causal relationship between subjective trust and behavioral trust is similar to that of perceived risk and risk taking. And third, we discuss the role of personal characteristics (such as risk propensity and trust propensity) in the risk-trust relationship. We also develop a number of propositions based on our risk-based view of trust.
One of the key issues in understanding the developmental processes of strategic alliances is how the alliance conditions change over the different stages of alliance development. A related question ...concerns the nature of the co‐evolutionary dynamics of alliances in terms of their constituent partner firms. In this article we propose an integrated process model of alliances that is based on alliance conditions, allianc developmental stages, and an alliance system comprising co‐evolutionary elements. We suggest that alliance conditions, or the key characteristics of an alliance at any given moment, link the alliance environment (firm characteristics) and the alliance development process. We also explore how specific patterns of alliance conditions have differential impacts on the interactive elements of the alliance co‐evolutionary system.
Possible bioaccumulation of pesticides in crop produce may cause ill effects on animals and humans. Tribenuron-methyl is a new post-emergence herbicide and is highly efficient to control the ...broad-leaf weeds in cereals, pasture, and plantation crops. There are scarce studies on its bioefficacy, sensitivity to weeds, tolerance to wheat, and persistence in crop produce, which are important information required before recommending an herbicide for use by the farmers. Weed control efficiency of an herbicide is dose-sensitive and site/soil-specific. Tribenuron-methyl (75 % DF) was applied at 22.5 and 45.0 g a.i./ha along with the surfactant 300.12 mL/ha as a tank mixes after 30 days of sowing in wheat as post-emergence herbicide. The samples of wheat foliage, soil, and grains at harvest were processed and analyzed for residues by high-performance liquid chromatography using a UV detector at 240 nm. The study revealed that there was a significant reduction in weed population and dry matter accumulation due to tribenuron-methyl application at a higher dose (45.0 g/ha) compared to a lower dose (of 22.5 g/ha). The weed density was found to be from 16.1 to 44.3 no/m
2
for application rate of 22.5 g/ha while at the 45.0 g/ha application, the weed density was 5.3–5.9 as compared to untreated control, where 184.3–120.5 no/m
2
was observed. The yield varied from 4.30 to 4.80 t/ha as compared to 2.25–3.55 t/ha in unweeded control with the LSD value being 21.5–16.3 to 0.27–0.19. Residues were below detectable level (BDL, <0.005 mg/kg) of tribenuron-methyl since they were detected in wheat grains at 22.5 g a.i./ha rates. However, 0.012 μg/g residues were detected in wheat foliage at an application rate of 45.0 g a.i./ha. It can be concluded that it is safe to use tribenuron-methyl at 22.5 g a.i./ha on wheat crop as post-emergence herbicide.
The unpromoted and promoted Fischer–Tropsch synthesis (FTS) catalysts were characterized using techniques such as X-ray diffraction (XRD), temperature programmed reduction (TPR), X-ray absorption ...spectroscopy (XAS), Brunauer–Emmett–Teller surface area (BET SA), hydrogen chemisorption and catalytic activity using a continuously stirred tank reactor (CSTR). The addition of small amounts of rhenium to a 15% Co/Al
2O
3 catalyst decreased the reduction temperature of cobalt oxide but the percent dispersion and cluster size, based on the amount of reduced cobalt, did not change significantly. Samples of the catalyst were withdrawn at increasing time-on-stream from the reactor along with the wax and cooled to become embedded in the solid wax for XAS investigation. Extended X-ray absorption fine structure (EXAFS) data indicate significant cluster growth with time-on-stream suggesting a sintering process as a major source of the deactivation. Addition of rhenium increased the synthesis gas conversion, based on catalyst weight, but turnover frequencies calculated using sites from hydrogen adsorption and initial activity were similar. A wide range of synthesis gas conversion has been obtained by varying the space velocities over the catalysts.
Background: Fallopian tubes are common surgical specimen in the pathology laboratory; still there is a lack of data to describe the frequency of various histological fi ndings. The aim and objectives ...of this study was to describe the various histopathological fi ndings of fallopian tubes. Materials and Methods: Two thousand fi ve hundred and seventy fi ve cases where fallopian tubes were removed either separately or along with other female genital tract organs were studied retrospectively and their histopathological fi ndings documented. Results: Ectopic pregnancy comprised maximum number of cases closely followed by salpingitis. Primary neoplastic lesions were rare as compared to secondary malignancies. Serial sections of fallopian tube and sections from representative areas are essential for a pathologist so that the diagnosis of these pathological entities is not missed. Conclusion: Though the fallopian tubes remain unremarkable in majority of the surgical pathological specimens, it must be subjected for histopathological examination to demonstrate the pathological lesions. Journal of Pathology of Nepal (2013) Vol. 3, No.1, Issue 5, 356-360 DOI: http://dx.doi.org/10.3126/jpn.v3i5.7858
Two-component systems play a central role in the adaptation of pathogenic bacteria to the environment prevailing within host tissues. The genes encoding the response regulator DevR (Rv3133c/DosR) and ...the cytoplasmic portion (DevS(201)) of the histidine kinase DevS (Rv3132c/DosS), a putative two-component system of Mycobacterium tuberculosis, were cloned and the protein products were overexpressed, purified and refolded as N-terminally His(6)-tagged proteins from Escherichia coli. DevS(201) underwent autophosphorylation and participated in rapid phosphotransfer to DevR in a Mg(2+)-dependent manner. Chemical stability analysis and site-directed mutagenesis implicated the highly conserved residues His(395) and Asp(54) as the sites of phosphorylation in DevS and DevR, respectively. Mutations in Asp(8) and Asp(9) residues, postulated to form the acidic Mg(2+)-binding pocket, and the invariant Lys(104) of DevR, abrogated phosphoryl transfer from DevS(201) to DevR. DevR-DevS was thus established as a typical two-component regulatory system based on His-to-Asp phosphoryl transfer. Expression of the Rv3134c-devR-devS operon was induced at the RNA level in hypoxic cultures of M. tuberculosis H37Rv and was associated with an increase in the level of DevR protein. However, in a devR mutant strain expressing the N-terminal domain of DevR, induction was observed at the level of RNA expression but not at that of protein. DevS was translated independently of DevR and induction of devS transcripts was not associated with an increase in protein level in either wild-type or mutant strains, reflecting differential regulation of this locus during hypoxia.
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