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The main purpose is to study analytically about the Diffusion-thermo impact on mixed convective flow of Casson fluid in a vertical channel in occurrence of porous media, uniform magnetic field and amplification. Similarity transformation is implemented to transform nonlinear coupled PDEs into ODEs. Further, obtained equations were solved using perturbation technique and studied the characters of heat, velocity and concentration of the corporeal system. The influence of nondimensional factors such as Darcy number Da, buoyancy parameter of concentration N, M2 Hartmann number, dufour number df, rate of chemical reaction γ, Schmidt number Sc, thermal buoyancy parameter λ, Prandtl number Pr, Casson parameter β, and Reynolds number R on concentration, temperature and velocity deliberated explicitly. Few important computational work reveals that the Dufour effect Df enhances the concentration, temperature and fluid flow whereas Casson fluid parameter β diminishes the profiles. The earlier work and present work have been compared for a particular case in the nonexistence of Dufour effect and porous media and were found to be coinciding. [ABSTRACT FROM AUTHOR]

The hot and semi-arid region is prone to meteorological droughts; the lack of rain is frequently accompanied by hot temperatures, strong winds, and low humidity, which has the impact of limiting nutrient uptake and agricultural yields. To overcome this problem a field study conducted during June, 2020 kharif season at farmers field, Chinna Dudyala village, Muddanur, Kadapa district, Andhra Pradesh aimed to determine the effect of organic mulches and foliar spray of kaolin on NPK uptake in enhancing yield and economics of dry land maize (Zea mays). One of the most important techniques for preserving soil moisture was mulching, which also reduces evapotranspiration when anti-transpirants are used. The experiment comprised nine treatments (T1 to T9) with four types of organic mulches viz., Paddy straw, Ground-nut haulm, Coir-pith, and Sugarcane trash, with foliar spray of kaolin intervals on 40 DAS, 20 & 40 DAS and farmers practice to minimize water stress and improve the nutrient uptake by plant. Among the application of the treatments, coir-pith mulch + foliar spray of kaolin @ 3.0% (T6) on 20 DAS & 40 DAS had significant effect on NPK uptake with N (187.15 kg ha-1), P (69.60 kg ha-1) and K (156.22 kg ha-1) and enhanced grain yield (6976 kg ha-1) and stover yield (10980 kg ha-1), highest gross returns (138034 ₹. ha-1) and BCR (2.63) and was superior to all the other treatments. The present study would help to effectively utilise the available resources, enhance growth and productivity in maize crop and to make economically viable to the farmers of semi-arid regions. [ABSTRACT FROM AUTHOR]

Background:A surgically created or unintentionally formed opening of the intestinal or urinary system onto the abdominal wall is known as intestinal stoma. The connection between the colon and the skin of the abdominal wall is known as a colostomy and when ileum is externalized on the abdomen skin is known as ileostomy. OBJECTIVES: 1) To study different types of intestinal stomas, their indications. 2) To study various complications that occurred after the construction of intestinal stomas. 3) To study the ways how these complications can be minimized and managed in a better way Material & Methods: Study Design: A prospective observational study. Study area: The study was done at surgery department, Subbaiah Institute of Medical Sciences, Shimoga. Study Period: Sep. 2021 - March 2022. Study population: Patients who underwent intestinal stomas either ileostomy or colostomy either in elective or emergency setting with postoperative complications of intestinal stomas. Sample size: 30 cases were included in our study. Sampling method: Simple Random sampling method. Study tools and Data collection procedure: Patients who underwent intestinal stomas either ileostomy or colostomy either in elective or emergency setting with postoperative complications of intestinal stomas were included in the study. The indications for the stoma, temporary, permanent, end or loop or double barrel, ileostomy or colostomy and their complications were recorded. Patients were followed up in the postoperative period for about 6 months or till the revision of stoma for early and late postoperative complications and their complications were recorded and analyzed. Results: Ileostomy was the most common type of stoma (23 out of 30) 76.66% and then colostomy (7 out of 30) 23.33%. Among ileostomy, loop ileostomy was done 10 patients followed by end ileostomy done in 7 patients then double barrel was done in 6 patients. Among colostomy, end colostomy was most commonly done in 6 patients followed by descending loop colostomy done in 1 patient. CONCLUSION: Preoperative stoma site marking for optimal stoma location and proper preoperative education by WOC nurses will increase the patient's independence in stoma care and resumption of normal activities, estimate pouching system wear times, and prevent postoperative complications. [ABSTRACT FROM AUTHOR]

The notable unbiased of this research work was to evaluate the well-being and effectiveness of metaxalone by administering the newly developed test and reference drug. A two-period, two-categorization, crossover bioavailability study in fed conditions. Eleven participants were dosed and completed the trial successfully. The drugs were administered by way of a schedule. Samples collected in both periods for pharmacokinetic evaluation. Plasma samples analyzed using a validated method. Pharmacokinetic parameters for investigational and reference products were calculated using the metaxalone drug concentration and safety of the participants monitored by measurement of vital sign. Relative estimation factors calculated for Cmax, Tmax, area under the curve (AUC) t, AUC inf, K el, half-life, and 90% confidence intervals applied for to check for whether reference and test products are equivalent. The experimental part of the study was completed with no major adversarial event. No losses or stern adverse events transpired throughout the course of the experiment. The assessment product is analogous to reference product in relation to degree and extent of absorption. The outcome of this study indicates the newly developed drug is equivalent to the innovator drug and medication was well tolerated by all participants. [ABSTRACT FROM AUTHOR]

Protective coatings enriched with different types of chemical additives, functional fillers, and nanostructured materials are gaining immense interest to minimize corrosion. The present work demonstrates the synthesis of chemically functionalized reduced graphene oxide (rmGO) and emeraldine salt form of polyaniline (PANI-ES)-based rmGO-PANI-ES nanocomposites as protective functional fillers for epoxy coating to inhibit mild steel corrosion. The oxidative polymerization of aniline into PANI-ES is initiated on nitrogen-rich active sites of rmGO, and it propagates along the basal plane of rmGO, eventually enwrapped the graphene sheets by interfacially grown PANI-ES. The synthesis of rmGO-PANI-ES nanocomposites and their chemical, morphological, crystalline, and structural characteristics are examined by the FTIR, 13C NMR, XPS, XRD, Raman, SEM, and HRTEM analyses. The multiple interactions between the highly polar nitrogen-rich rmGO-PANI-ES nanocomposites and the epoxy matrix strengthened the coating and increased the hardness and elastic modulus. The corrosion inhibition performance of epoxy coating enriched with the rmGO-PANI-ES nanocomposites is probed by electrochemical impedance spectroscopic (EIS) and salt spray tests using an accelerated corrosive environment (3.5 wt% NaCl). The rmGO-PANI-ES-15 nanocomposite having 0.15 wt% rGO in epoxy coating showed superior corrosion inhibition performance. The total electrochemical impedance of epoxy coating (8.7 ×103 Ω.cm2) increased to 4.7 ×1015 Ω.cm2 after incorporating 1 wt% rmGO-PANI-ES-15 nanocomposite. The enhancement of electrochemical impedance by ∼12 orders of magnitude demonstrates the effectiveness of the rmGO-PANI-ES nanocomposites for corrosion mitigation in a harsh corrosive environment. The high surface area and remarkable structural barrier of the 2D chemically functionalized graphene furnished excellent protective coverage. The PANI-ES of rmGO-PANI-ES nanocomposites formed a passive layer of fully reduced leucoemeraldine base of PANI (PANI-LEB) on the coating-mild steel interface by accepting the electrons, generated during the anodic oxidation of iron. These events collectively increase the impedance by multifolds and inhibit steel corrosion. The present findings revealed that graphene-enriched conductive polymeric nanocomposites-based coatings can be promising solution to mitigate corrosion of metal-based installations in a marine environment. [Display omitted] • Graphene-polyaniline (rmGO-PANI-ES) nanocomposites as protective filler to epoxy coating for corrosion inhibition. • Interfacially grown PANI wrapped the chemically-functionalized graphene in these nanocomposites. • rmGO-PANI-ES strengthened the epoxy coating and increased hardness and elastic modulus. • rmGO-PANI-ES in epoxy coating increased the impedance by 12 orders of magnitude under a harsh corrosive environment. [ABSTRACT FROM AUTHOR]

Corrosion, a major concern in many industries, is primarily accountable for high maintenance costs, material degradation, frequent repair/replacement, and poor lifespan of structural installations. Eventually, corrosion can lead to a high risk of catastrophic equipment failures and environmental threats such as leakage from pipelines and chemical containers. Protective coatings enriched with nanostructured fillers that impart enhancement of corrosion inhibition properties are gaining immense interest. In the present work, nanocomposites comprising N-doped graphene (NGr) wrapped by emeraldine salt form of polyaniline (PANI-ES) are developed as highly effective protective functional fillers to epoxy coatings for mild steel corrosion inhibition. The NGr-PANI-ES nanocomposites furnished excellent structural strengthening to epoxy coatings and are able to impede the penetration of corrodents to a significant extent. The corrosion inhibition performance of the NGr-PANI-ES nanocomposites-based epoxy coatings is evaluated by electrochemical impedance spectroscopy and salt spray tests. The nitrogen incorporation into graphene skeleton introduced ample electron-rich nitrogen-based functionalities as revealed by XPS analysis, which synergistically amplified corrosion inhibition performance with PANI-ES. The NGr-PANI-ES nanocomposites in epoxy coatings enhanced the total impedance in a highly aggressive corrosive electrolyte (3.5 % NaCl) by a magnitude of 12 orders, corroborating with excellent corrosion inhibition performance results based on salt spray tests. The improved corrosion inhibition properties are collectively attributed to the structural barrier by 2D N-doped graphene, compatibility of NGr-PANI-ES nanocomposites with epoxy matrix to strengthen the coatings, and the synergistic inhibition of the anodic reactions by PANI-ES and N-doped graphene that underpin the corrosive events. [Display omitted] • Polyaniline-N-doped graphene (NGr-PANI-ES) nanocomposites for steel corrosion inhibition • NGr-PANI-ES furnished excellent strengthening to epoxy coatings to impede corrodent penetration. • NGr-PANI-ES in epoxy coatings increased total impedance by a magnitude of 12 orders. • NGr-PANI-ES-based coatings showed remarkably high corrosion inhibition against salty fog. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy)–molybdenum trioxide (MoO3) is a polymer‐metal oxide composite (99.9% pure) obtained when two are mixed mechanically with different wt% in acetone medium to obtain different PPy–MoO3 composite materials. The thick films of pure PPy and PPy–MoO3 polymer‐metal oxide composite are prepared by screen printing technique. The prepared mixed composite polymer‐metal oxide materials are calcinated at 800°C for 8 h in air. The thick films are investigated for structural, electrical, and morphological properties. The surface morphology of the thick films is studied by scanning electron microscope (SEM) which shows that the films are granular and porous in nature. The gas responses of pure PPy and PPy–MoO3 polymer‐metal oxide composite thick films are studied for different gases such as ammonia gas (NH3) and ethanol gas at room temperature. The pure PPy thick film shows the poor response to ammonia and ethanol gas, while the thick film 40PPy–60MoO3 gave good responses to ethanol gas (50 ppm) at room temperature. The gas selectivity, sensitivity, stability, gas response, and recovery time of the sensor are measured and presented. [ABSTRACT FROM AUTHOR]

Tm3+‐doped La2O3 phosphors with different doping concentration are prepared by co‐precipitation method. The prepared phosphor is characterized by X‐ray powder diffraction (XRD), SEM, Fourier transform infrared (FT‐IR) spectroscopy, and photoluminescence (PL) techniques. The XRD analysis confirms the formation of La2O3. PL measurement shows that the phosphor exhibit characteristic Tm3+ bright blue emission attributed to transition from 1D2 → 3F4 of Tm3+ ions, at 363 nm excitation. The Commission International de I'Eclairage (CIE) chromaticity color coordinates of prepared phosphor is calculated and presented. The excitation peak located at 363 nm matches with the emission wavelength of near UV‐LED chip, this indicates that the prepared phosphor is a promising blue light‐emitting candidate for eco‐friendly solid state lighting (W‐LED) application. [ABSTRACT FROM AUTHOR]

Accurate crop disease prediction and continuous monitoring is essential in agriculture to improve the crop yield. Internet of Things(IoT) are being used in developing decision support systems for traditional farming methods to optimize disease estimation and yield estimation. Traditionally, a large numbers of statistical and scientific models have been implemented to monitor and predict the crop yield estimation in the agriculture fields. However, most of these models are limited to small and fixed number of agriculture characteristics. Image processing and machine learning approaches are used to predict the disease on agricultural crops using IoT devices. As the size of the training images and features increases, these approaches are incorporate to find and analyze the crop yield in agriculture field. In this paper, we have studied and analyzed various agricultural crop monitoring approaches using IoT based image and machine learning techniques. IoT based image processing and machine learning approaches are necessary for the process of agricultural crop monitoring. Furthermore, we have also studied the advantages and limitations of these approaches on complex crop data. [ABSTRACT FROM AUTHOR]

In this research work an attempt has been made to reduce the waste materials in the environment and reuse it in our research effectively and efficiently, so we adopted to make a comparative study of bricks made with various waste materials to conventional clay brick. We have done a study on brick made with each and every waste material available in the environment and selected waste materials to be partially replaced to clay brick. From that analysis, we adopted steel slag, saw dust and construction and demolition waste for the partial replacement to clay. Before replacement of waste materials, we analyzed the chemical and physical properties of clay as well as the waste materials. We replaced our waste materials to clay by 10%, 20%, 30%, 40%, 50% of steel slag, construction and demolition waste and saw dust. The bricks have been casted in a chamber with reference to IS 1077:1992. Casted bricks are dried up by using oven and then dispatched for testing. The tests such as compression test, water absorption test and efflorescence test are done with reference to IS 3495:1994 Part I to IV. These test results are compared with conventional clay bricks to find out optimal replacement of particular waste material that produce the maximal strength. [ABSTRACT FROM AUTHOR]

• Bacillus Sphaericus possesses maximum urease activity and therefore, is suitable to be used for bacterial calcite precipitation in concrete. • Cement was replaced with MBS at various percentage levels. The strengths and durability characteristics were evaluated. • An improvement in strength and durability was observed with an optimum level of 8% MBS and 20 ml bacteria. • Through XRD analysis, it was observed that with MBS and bacteria, the intensity of peaks is higher. • The cracks were visualized for 3 days and 7 days which confirmed the healing of cracks due to the formation of calcite precipitate. The main idea of this study is to evaluate the mechanical and durability properties of high strength concrete specimens by incorporating an alternative for cement along with bacteria for healing cracks. The classic methods which are used for healing cracks involve the use of ordinary synthetic polymers which further cause a lot of damage to the environment. Therefore, the use of sustainable strategies like ingesting bacterial culture into the concrete mix along with an alternative replacement for cement can act as an active support for both nature as well as construction industries. In this paper, control concrete, concrete made by replacing cement with Micronized Biomass Silica (MBS) at 4%, 8% and 12% and bacteria induced concrete are compared. The bacteria used is Bacillus Sphaericus with optical density as 1.00 and is mixed in control as well as MBS made concrete specimens at different levels of 10 ml, 20 ml, 30 ml for each. With a total of 16 mix designs of characteristic compressive strength 60 N/mm2 at the age of 28 days curing (M60 grade) high strength concrete cubes, cylinders and beams are compared on grounds of compressive strength, splitting tensile, flexural strengths, water absorption and sorptivity. It was concluded that, specimens with 8% MBS and 20 ml bacteria showed optimum results based on strength and durability characteristics. Further, an artificial crack was induced in the specimen and the bacteria's healing activities along with calcite precipitation were examined through X-Ray diffraction, Scanning Electron Microscope (SEM) and visualization analysis. A high intensity of peaks was observed with MBS and bacteria and the cracks were visualized for 3 days and 7 days which ratified the healing of cracks due to the formation of calcite precipitate which was confirmed through SEM Analysis. [ABSTRACT FROM AUTHOR]

Convective heat transmission of $Ti{O_2} - EG$TiO2−EG nanoliquid under slip and convective regime in a microchannel is examined using a modified Buongiorno model. The fractal-based approach is employed to describe the aggregation of nanoparticles. The impact of molecular dynamics, particularly on dynamic viscosity and thermal conductivity due to the aggregation of nano-sized particles, is simulated with the help of two significant models: namely, the Krieger-Dougherty model and the Maxwell-Bruggeman model, respectively. The aspect of the interfacial layer enables us to get a realistic nanoliquid model. The solutions for the designed nondimensional mathematical model are obtained numerically. The variation in flow and thermal distribution for pertinent parameters are visualized graphically. The study reveals that the thermophysical characteristics sturdily depend on nanoparticle concentration and cluster formation. It is emphasized that the viscous dissipation and radiative heat transfer contribute towards magnifying the irreversibilities in a microchannel. The findings are useful in bioconvection and various heat transfer applications. [ABSTRACT FROM AUTHOR]

In this study, polypropylene (PP), a versatile commodity thermoplastic, and cyclic olefin copolymer (COC), an amorphous engineering thermoplastic, were blended over full composition range by melt-mixing technique using a co-rotating twin-screw extruder. PP is likely to be compatible with COC due to its olefinic behaviour, and PP/COC blends provide significant promising properties. FTIR spectra, Raman spectra and wide-angle X-ray scattering (WAXS) patterns of polypropylene, cyclic olefin copolymer and its blends were recorded in solid phases and carried out qualitative and quantitative analysis in detail. The characteristic absorption peaks of PP, COC and PP/COC blends were determined and compared. PP/COC blends did not generate new chemical reactions, while the intensity of fundamental vibration peaks in the spectra tends to vary with respect to the component contents in the blends. The ratio of the integral intensities of polypropylene and cyclic olefin copolymer fundamental vibrations in the Raman spectra were used for the quantitative analysis of PP/COC blends, and the obtained results showed very good agreement with the experimental values. IR spectra, Raman spectra and WAXS patterns of PP/COC blends are useful to track the uniformity of blending and determine the blend composition. [ABSTRACT FROM AUTHOR]

Background: Coronary artery disease (CAD) has become the most common cause of mortality in the entire world. Homocysteine is implicated as an early atherosclerotic promoter. Homocysteine (Hcy) is an essential amino acid in humans. It has been known as a novel and independent risk factor for coronary heart disease (CHD). The prevalence of hyperhomocysteinemia varies between 5% and 30% in the general population. Aim of the study: To assess whether hyperhomocysteinemia is one of the independent risk factors for coronary artery disease. Materials and methods: The study was conducted in the Department of General Medicine, Government K.A.P. Viswanatham Medical College, Trichy from 2017-2018. Totally 100 Patients who were presented to our hospital with coronary artery disease of age group 30 to 70 years were included in the study. Diagnosis of coronary artery disease was made based on a history of angina pain, electrocardiography (ECG) changes and cardiac enzyme levels. Diagnosis of acute MI was made according to WHO criteria. Results: Among the 100 patients, 66 had acute Myocardial Infarction and 34 had angina. Among the 52 patients who had hyperhomocysteinemia, 34 patients (65%) were young with age = 45 years and 18 patients (35%) were with age> 45 years. In our study, 66 patients with MI were included. Among the 28 patients (42.4%) were young with age <45 years. In this group of young patients with MI, 21 patients (65.4%) had hyperhomocysteinemia and 7 patients (34.6%) had normal homocysteine level. Conclusion: Finally, during the last decade, the utility of homocysteine in predicting risk for atherothrombotic vascular disease has been evaluated in several observational studies in a large number of patients. These studies show that the overall risk for vascular disease is small, with prospective, longitudinal studies reporting a weaker association between homocysteine and atherothrombotic vascular disease compared to retrospective case-control and cross-sectional studies. Furthermore, randomized controlled trials of homocysteine-lowering therapy have failed to prove a causal relationship. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the Zn doped haematite nanoparticles (NPs) which were synthesized through co-precipitation route and annealed in air at different temperatures: 600 and 800°C. The single phase nature has been confirmed via X-ray diffraction (XRD). The average of crystallite sizes increased progressively ranging between 33 nm and 49.7 nm as the thermal annealing increased . The obtained results confirmed the single-phase Zn doped alpha-Fe2O3 nanoparticles. The results of magnetic measurements made at room temperature indicate a significant improvement in the ferromagnetic order which could be understood as due to the creation of oxygen vacancies and magneto crystalline anisotropic effects due to doping. The present study indicates that doping ions may be considered as a general approach to stimulate or tune the optical and magnetic properties of nanomaterials. [ABSTRACT FROM AUTHOR]

Introduction: Hyperlipidemia, one of the important risk factor of atherosclerosis, is an abnormality commonly encountered in patients with chronic kidney disease. There are several other important risk factors, such as smoking, proteinuria, oxidative stress, inflammation and dyslipidemia that independently or in combination with elevated blood pressure, can cause deterioration in renal function. Aim of the study: To analyze lipid alterations that can occur in chronic kidney disease patients. Materials and methods: This study was conducted among 50 patients with chronic kidney disease. All the patients with established chronic kidney disease ensured with radiological evidence and on conservative treatment were included in the study. Lipid profile parameters are estimated under standard techniques. Results: Total cholesterol (TC), Triglycerides (TGL), High-Density Lipoprotein (HDL), and Low- Density Lipoprotein (LDL) of all the patients were investigated for the lipid profile study. It was found that the majority (80%) of the study participants were found to have low HDL, 62% of the participants were found to have a high triglyceride level. Overall, seven patients (14%) showed abnormal lipid profile with respect to all the four parameters. Conclusion: HDL-C levels were lower and triglycerides, total cholesterol, and TGL levels were higher in the study group. There is a statistically significant increase in serum triglycerides level in patients with CKD stage 3, 4 and 5. Predominant lipid abnormalities were reduced HDL-C levels and elevated TGL. [ABSTRACT FROM AUTHOR]

Several Markov modulated Poisson process (MMPP) models are developed to describe winter season rainfall with parsimonious parameter use. We propose a methodology for determining the best form of seasonal model for fine-scale rainfall within a MMPP framework. Of those proposed here, a model with a fixed transition rate is shown to be superior over the other MMPP models considered. The model is expanded to include covariate data for sea-level air pressure, relative humidity, and temperature using reanalysis data over 14 years from the coordinates covering the Bracknell rainfall collection site in England. Results are compared using the likelihood ratio test and the second-order properties of aggregated rainfall. [ABSTRACT FROM AUTHOR]

We develop a doubly stochastic point process model with exponentially decaying pulses to describe the statistical properties of the rainfall intensity process. Mathematical formulation of the point process model is described along with second-order moment characteristics of the rainfall depth and aggregated processes. The derived second-order properties of the accumulated rainfall at different aggregation levels are used in model assessment. A data analysis using 15 years of sub-hourly rainfall data from England is presented. Models with fixed and variable pulse lifetime are explored. The performance of the model is compared with that of a doubly stochastic rectangular pulse model. The proposed model fits most of the empirical rainfall properties well at sub-hourly, hourly and daily aggregation levels. [ABSTRACT FROM AUTHOR]

Cyanobacteria are among the most abundant organisms present on earth and are considered to be one of the oldest known clades. Cyanobacteria are oxygenic photosynthetic bacteria and are well known as promising renewable sources of energy; therefore, it is important to understand aspects of their genomes in detail across species. Advances in sequencing technology and the availability of several cyanobacterial genomes have provided an excellent opportunity to understand the diversity and evolution of the cyanobacterial genome. Here, we compared the genomes of 62 different phototrophic cyanobacteria. Evaluation of genetic diversity of all the cyanobacteria species studied revealed that evolution from their common ancestors was polyphyletic. In addition, the genomes were very diverse and varied among species, and significant genomic diversity was observed at the species and strain level. Overall, we identified 56 different protein families of cyanobacteria species/strains and found that they varied significantly among strains of a species. The circadian clock proteins KaiA, KaiB and KaiC (KaiABC complex proteins) of cyanobacteria were found to be present and consistent in the majority of cyanobacterial species while absent in a few others. Evolutionary analysis of the KaiABC protein complex showed that the KaiA protein has a high frequency of polymorphism, and multiple alleles were found to be present at high frequency. These results demonstrated that evolution of phosphorylation events occurred via KaiA in the KaiABC complex. Furthermore, multiple sequence alignment showed that KaiA, KaiB and KaiC proteins are highly conserved in nature. Our results provide direct information regarding the presence of different protein or protein families in cyanobacteria. The information presented here will serve as a starting point to explore the genetic diversity of cyanobacteria with the potential to play important roles in biotechnological applications. [ABSTRACT FROM PUBLISHER]

Stochastic rainfall models are widely used in hydrological studies because they provide a framework not only for deriving information about the characteristics of rainfall but also for generating precipitation inputs to simulation models whenever data are not available. A stochastic point process model based on a class of doubly stochastic Poisson processes is proposed to analyse fine-scale point rainfall time series. In this model, rain cells arrive according to a doubly stochastic Poisson process whose arrival rate is determined by a finite-state Markov chain. Each rain cell has a random lifetime. During the lifetime of each rain cell, instantaneous random depths of rainfall bursts (pulses) occur according to a Poisson process. The covariance structure of the point process of pulse occurrences is studied. Moment properties of the time series of accumulated rainfall in discrete time intervals are derived to model 5-min rainfall data, over a period of 69 years, from Germany. Second-moment as well as third-moment properties of the rainfall are considered. The results show that the proposed model is capable of reproducing rainfall properties well at various sub-hourly resolutions. Incorporation of third-order moment properties in estimation showed a clear improvement in fitting. A good fit to the extremes is found at larger resolutions, both at 12-h and 24-h levels, despite underestimation at 5-min aggregation. The proportion of dry intervals is studied by comparing the proportion of time intervals, from the observed and simulated data, with rainfall depth below small thresholds. A good agreement was found at 5-min aggregation and for larger aggregation levels a closer fit was obtained when the threshold was increased. A simulation study is presented to assess the performance of the estimation method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graphene-PANI (fGO-PANI) nanocomposites are demonstrated as smart functional fillers to epoxy coatings for minimizing corrosion. • π-π interactions driven interfacial wrapping of graphene by PANI during fGO-PANI synthesis. • PANI-ES showed higher impedance and corrosion inhibition compared to PANI-EB. • fGO-PANI composites enhanced anticorrosive properties of PANI by multifold increase in total impedance. Present work addresses the synthesis of different structural forms of polyaniline (PANI) and their nanocomposites with graphene as functional fillers to epoxy coating for minimizing mild steel corrosion. The π-π interactions between p -phenylenediamine functionalized graphene (fGO) and aromatic rings of in-situ grown covalently linked PANI on fGO facilitated the interfacial wrapping of graphene skeleton by PANI. The chemical, morphological, crystalline, and structural features of fGO-PANI nanocomposites are probed by FTIR, NMR, Raman, XPS, XRD, SEM, and HRTEM analyses. The emeraldine salt form of PANI (PANI-ES) exhibited significantly higher impedance and better corrosion inhibition properties than the emeraldine base (PANI-EB). Graphene skeleton in the fGO-PANI nanocomposite notably enhanced the anticorrosive properties of PANI with a multifold increase in total impedance. The 2D graphene skeleton in fGO-PANI nanocomposites provides excellent surface coverage as a structural barrier and increases the number of possible electron transfer pathways. Moreover, the oxidoreduction properties of PANI make the fGO-PANI-ES nanocomposite highly effective in increasing the impedance by multifolds. The corrosion protective mechanism of fGO-PANI-ES is discussed by emphasizing the role of graphene, different structural forms of PANI, and the dosing of graphene in fGO-PANI nanocomposites. The present work revealed fGO-PANI-ES as a promising material for new generation coatings to mitigate mild steel corrosion, particularly in a maritime environment. [ABSTRACT FROM AUTHOR]

The W4 locus in soybean encodes a dihydroflavonol-4-reductase (DFR2) that regulates pigmentation patterns in flowers and hypocotyl. The mutable w4-m allele that governs variegated flowers has arisen through insertion of a CACTA-type transposable element, Tgm9, in DFR2. In the w4-m line, reversion from variegated to purple flower indicates excision of Tgm9, and its insertion at a new locus. Previously, we have identified a male-sterile, female-sterile mutant among the selfed progenies of a revertant plant carrying only purple flowers. Co-segregation between Tgm9 and the sterility phenotype suggested that the mutant was generated by insertion of Tgm9 at the St8 locus. The transposon was localized to exon 10 of Glyma.16G072300 that shows high identity to the MER3 DNA helicase involved in crossing over. Molecular analysis of fertile branches from two independent revertant plants confirmed precise excision of Tgm9 from the st8 allele, which restored fertility. In soybean, the gene is expressed in flower-buds, trifoliate leaves and stem. Phylogenetic analysis placed St8 in a clade with the Arabidopsis and rice MER3 suggesting that St8 is most likely the orthologous MER3 soybean gene. This study established the utility of Tgm9 in gene identification as well as in forward and reverse genetics studies. [ABSTRACT FROM AUTHOR]

Chirality is a key factor in the safety and efficacy of many drug products and thus the production of single enantiomers of drug intermediates and drugs has become increasingly important in the pharmaceutical industry. There has been an increasing awareness of the enormous potential of microorganisms and enzymes derived there from for the transformation of synthetic chemicals with high chemo-, regio- and enatioselectivities. In this article, biocatalytic processes are described for the synthesis of chiral alcohols and unntural aminoacids for pharmaceuticals. [ABSTRACT FROM AUTHOR]

Point process models for rainfall are constructed generally based on Poisson cluster processes. Most commonly used point process models in the literature were constructed either based on Bartlett-Lewis or Neyman-Scott cluster processes. In this paper, we utilize a class of Cox process models, termed the Markov modulated Poisson process (MMPP), to model rainfall intensity. We use this class of models to analyse rainfall data observed in the form of tip time series from rain gauge tipping buckets in a network of gauges in Somerset, southwest England, recorded by the Hydrological Radar Experiment (HYREX). Univariate and multivariate models are employed to analyse the data recorded at single and multiple sites in the catchment area. As the structure of this proposed class of MMPP models allows us to construct the likelihood function of the observed tip time series, we utilize the maximum likelihood methods in our analysis to make inferences about the rainfall intensity at sub-hourly time scales. The multivariate models are used to analyse rainfall time series jointly at four stations in the region. Properties of the cumulative rainfall in discrete time intervals are studied, and the results of fitting three-state models are presented. [ABSTRACT FROM AUTHOR]

We consider a class of doubly stochastic Poisson process models in the modelling of fine-scale rainfall at multiple gauges in a dense network. Multi-site stochastic point process models are constructed and their likelihood functions are derived. The application of this class of multi-site models, a useful alternative to the widely-known Poisson cluster models, is explored to make inferences about the properties of fine time-scale rainfall. The proposed models, which incorporate covariate information about the catchment area, are used to analyse tipping-bucket raingauge data from multiple sites. The results show the potential of this class of models to reproduce temporal and spatial variability of fine time-scale rainfall characteristics. [ABSTRACT FROM AUTHOR]

Contaxt: Every year in India 6000 to 8000 children are born with thalassaemia major. The birth of such a child produces considerable physical and economic strain on the affected child, its family and the community at large. Thus, the emphasis must shift from the treatment to the prevention of such births in the future. Aims: To find out the prevalence of the Beta Thalassaemia trait among the pregnant women who attended the antenatal clinics in a Primary Health Centre, by using the NESTROF test; to describe the socio-demographic characteristics of the study subjects, to find out the pregnancies which were 'at risk' of delivering babies with Thalassaemia major and to find out the 'awareness' of the pregnant women regarding Thalassaemia. Material and Methods: This exploratory study was conducted in a PHC which was attached to the Department of Community Medicine of a medical college which was situated in Bangalore, India, for a period of 3 months. All the pregnant women who attended the antenatal clinic and the husbands of the NESTROF positive women were included in the study. The details regarding the sociodemographic characteristics of the women were collected on a structured proforma and the NESTROF test was performed. Results: Out of the 210 pregnant women who were tested, 18 (8.5%) were thalassaemia carriers. 12 (66.6%) of them were between 20 - 25 years of age. 5 (27.7%) were born out of 2nd degree consanguineous marriages. 7 (38.8%) had a history of abortions, among which 6 (33.3%) were in the 1st trimesters of their pregnancies. Out of the 18 positive women, 9 (50%) had turned up with their husbands. All of the husbands were negative for the Thalassaemia carrier status. Thus, there was no pregnancy which was at a risk of delivering babies with thalassaemia major. None (100%) of the pregnant women were aware of the disease, thalassaemia. Conclusions: The prevalence of the Beta Thalassaemia trait among the pregnant women was 8.5%. [ABSTRACT FROM AUTHOR]

Time series of rainfall bucket tip times at the Beaufort Park station, Bracknell, in the UK are modelled by a class of Markov modulated Poisson processes (MMPP) which may be thought of as a generalization of the Poisson process. Our main focus in this paper is to investigate the effects of including covariate information into the MMPP model framework on statistical properties. In particular, we look at three types of time-varying covariates namely temperature, sea level pressure, and relative humidity that are thought to be affecting the rainfall arrival process. Maximum likelihood estimation is used to obtain the parameter estimates, and likelihood ratio tests are employed in model comparison, Simulated data from the fitted model are used to make statistical inferences about the accumulated rainfall in the discrete time interval. Variability of the daily Poisson arrival rates is studied. [ABSTRACT FROM AUTHOR]

:Mice lacking the α isoform of the catalytic subunit of calcineurin (CnAα) were first reported in 1996 and have been an important model to understand the role of calcineurin in the brain, immune system, bones, muscle, and kidney. Research using the mice has been limited, however, by failure to thrive and early lethality of most null pups. Work in our laboratory led to the rescue of CnAα−/− mice by supplemental feeding to compensate for a defect in salivary enzyme secretion. The data revealed that, without intervention, knockout mice suffer from severe caloric restriction. Since nutritional deprivation is known to significantly alter development, it is imperative that previous conclusions based on CnAα−/− mice are revisited to determine which aspects of the phenotype were attributable to caloric restriction versus a direct role for CnAα. In this study, we find that defects in renal development and function persist in adult CnAα−/− mice including a significant decrease in glomerular filtration rate and an increase in blood urea nitrogen levels. These data indicate that impaired renal development we previously reported was not due to caloric restriction but rather a specific role for CnAα in renal development and function. In contrast, we find that rather than being hypoglycemic, rescued mice are mildly hyperglycemic and insulin resistant. Examination of muscle fiber types shows that previously reported reductions in type I muscle fibers are no longer evident in rescued null mice. Rather, loss of CnAα likely alters insulin response due to a reduction in insulin receptor substrate-2 (IRS2) expression and signaling in muscle. This study illustrates the importance of re-examining the phenotypes of CnAα−/− mice and the advances that are now possible with the use of adult, rescued knockout animals. [ABSTRACT FROM AUTHOR]

Characterization of reactant gas flow patterns in the underground coal gasification (UCG) cavity is important, because the flow is highly nonideal and likely to influence the quality of the product gas. In our earlier work [Daggupati et al., Energy2010, 35, 2374–2386], we have demonstrated a computational fluid dynamics (CFD)-based modeling approach to analyze the flow patterns in the cavity. A compartment model (network of ideal reactors) for the UCG cavity was developed based on the CFD simulation results. These studies were performed assuming that the UCG cavity is isothermal. In reality, large temperature gradients may prevail under certain conditions and, in turn, may influence the flow patterns. In this work, we consider different possible nonisothermal scenarios in the UCG cavity and propose a simplified compartment modeling strategy to reduce the computational burden. We also examine the effect of various operating and design parameters such as coal spalling, feed flow rate, feed temperature, and orientation of the inlet nozzle. All these effects are quantified by determining the corresponding compartment model parameters. The sensitivity of the compartment model parameters, with respect to the changes in various conditions, is studied. Furthermore, we validate the compartment modeling approach by comparing predicted conversions for a water-gas shift reaction with that of reaction-enabled CFD simulations under nonisothermal conditions. The results presented here provide adequate insight into the UCG process and can be conveniently used in the development of a computationally inexpensive phenomenological process model for the complex UCG process. [ABSTRACT FROM AUTHOR]

Theories based on free-volume concepts have been developed to characterize the self and mutual-diffusion coefficients of low molecular weight penetrants in rubbery and glassy polymer-solvent systems. These theories are applicable over wide ranges of temperature and concentration. The capability of free-volume theory to describe solvent diffusion in glassy polymers is reviewed in this article. Two alternative free-volume based approaches used to evaluate solvent self-diffusion coefficients in glassy polymer-solvent systems are compared in terms of their differences and applicability. The models can correlate/predict temperature and concentration dependencies of the solvent diffusion coefficient. With the appropriate accompanying thermodynamic factors they can be used to model concentration profiles in mutual diffusion processes that are Fickian such as drying of coatings. The free-volume methodology has been found to be consistent with molecular dynamics simulations. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 [ABSTRACT FROM AUTHOR]

Background: Auxin signaling is vital for plant growth and development, and plays important role in apical dominance, tropic response, lateral root formation, vascular differentiation, embryo patterning and shoot elongation. Auxin Response Factors (ARFs) are the transcription factors that regulate the expression of auxin responsive genes. The ARF genes are represented by a large multigene family in plants. The first draft of full maize genome assembly has recently been released, however, to our knowledge, the ARF gene family from maize (ZmARF genes) has not been characterized in detail. Results: In this study, 31 maize (Zea mays L.) genes that encode ARF proteins were identified in maize genome. It was shown that maize ARF genes fall into related sister pairs and chromosomal mapping revealed that duplication of ZmARFs was associated with the chromosomal block duplications. As expected, duplication of some ZmARFs showed a conserved intron/exon structure, whereas some others were more divergent, suggesting the possibility of functional diversification for these genes. Out of these 31 ZmARF genes, 14 possess auxin-responsive element in their promoter region, among which 7 appear to show small or negligible response to exogenous auxin. The 18 ZmARF genes were predicted to be the potential targets of small RNAs. Transgenic analysis revealed that increased miR167 level could cause degradation of transcripts of six potential targets (ZmARF3, 9, 16, 18, 22 and 30). The expressions of maize ARF genes are responsive to exogenous auxin treatment. Dynamic expression patterns of ZmARF genes were observed in different stages of embryo development. Conclusions: Maize ARF gene family is expanded (31 genes) as compared to Arabidopsis (23 genes) and rice (25 genes). The expression of these genes in maize is regulated by auxin and small RNAs. Dynamic expression patterns of ZmARF genes in embryo at different stages were detected which suggest that maize ARF genes may be involved in seed development and germination. [ABSTRACT FROM AUTHOR]

Abstract: Systematic laboratory scale experiments on coal blocks can provide significant insight into the underground coal gasification (UCG) process. Our earlier work has demonstrated the various features of the early UCG cavity shape and rate of growth through lab-scale experiments on coal combustion, wherein the feed gas is oxygen. In this paper, we study the feasibility of in situ gasification of coal in a similar laboratory scale reactor set-up, under conditions relevant for field practice of UCG, using an oxygen–steam mixture as the feed gas. By performing the gasification reaction in a cyclic manner, we have been able to obtain a product gas with hydrogen concentrations as high as 39% and a calorific value of 178kJ/mol. The effect of various operating parameters such as feed temperature, feed steam to oxygen ratio, initial combustion time and so on, on the product gas composition is studied and the optimum operating conditions in order to achieve desired conversion to syngas, are determined. We also study the effect of various design and operating parameters on the evolution of the gasification cavity. Empirical correlations are proposed for the change in cavity volume and its dimensions in various directions. The results of the previous study on the combustion cavity evolution are compared with this gasification study. [Copyright &y& Elsevier]

During underground coal gasification (UCG), a cavity is formed in the coal seam when coal is converted to gaseous products. This cavity grows three dimensionally in a nonlinear fashion as gasification proceeds. The cavity shape is determined by the flow field, which is a strong function of various parameters such as the position and orientation of the inlet nozzle and the temperature distribution and coal properties such as thermal conductivity. In addition to the complex flow patterns in the UCG cavity, several phenomena occur simultaneously. They include chemical reactions (both homogeneous and heterogeneous), water influx, thermomechanical failure of the coal, heat and mass transfer, and so on. Thus, enormous computational efforts are required to simulate the performance of UCG through a mathematical model. It is therefore necessary to simplify the modeling approach for relatively quick but reliable predictions for application in process design and optimization. The primary objective of this work is to understand the velocity distribution and quantify the nonideal flow patterns in a UCG cavity by performing residence time distribution (RTD) studies using computational fluid dynamics (CFD). The methodology of obtaining RTD by CFD is validated by means of of representative laboratory-scale tracer experiments. Based on the RTD studies, the actual UCG cavity at different times is modeled as a simplified network of ideal reactors, called compartments. The compartment model thus obtained could offer a computationally less expensive and easier option for determining UCG process performance at any given time, when used in a reactor-scale model including reactions. The network of ideal reactors can be easily simulated using a flowsheet simulator (e.g., Aspen Plus). We illustrate the proposed modeling approach by presenting selected simulation results for a single gas-phase second-order water−gas shift reaction. [ABSTRACT FROM AUTHOR]

Background: Auxin signaling is vital for plant growth and development, and plays important role in apical dominance, tropic response, lateral root formation, vascular differentiation, embryo patterning and shoot elongation. Auxin Response Factors (ARFs) are the transcription factors that regulate the expression of auxin responsive genes. The ARF genes are represented by a large multigene family in plants. The first draft of full maize genome assembly has recently been released, however, to our knowledge, the ARF gene family from maize (ZmARF genes) has not been characterized in detail. Results: In this study, 31 maize (Zea mays L.) genes that encode ARF proteins were identified in maize genome. It was shown that maize ARF genes fall into related sister pairs and chromosomal mapping revealed that duplication of ZmARFs was associated with the chromosomal block duplications. As expected, duplication of some ZmARFs showed a conserved intron/exon structure, whereas some others were more divergent, suggesting the possibility of functional diversification for these genes. Out of these 31 ZmARF genes, 14 possess auxin-responsive element in their promoter region, among which 7 appear to show small or negligible response to exogenous auxin. The 18 ZmARF genes were predicted to be the potential targets of small RNAs. Transgenic analysis revealed that increased miR167 level could cause degradation of transcripts of six potential targets (ZmARF3, 9, 16, 18, 22 and 30). The expressions of maize ARF genes are responsive to exogenous auxin treatment. Dynamic expression patterns of ZmARF genes were observed in different stages of embryo development. Conclusions: Maize ARF gene family is expanded (31 genes) as compared to Arabidopsis (23 genes) and rice (25 genes). The expression of these genes in maize is regulated by auxin and small RNAs. Dynamic expression patterns of ZmARF genes in embryo at different stages were detected which suggest that maize ARF genes may be involved in seed development and germination. [ABSTRACT FROM AUTHOR]

Abstract: PGC-1α is a transcriptional coactivator that controls energy homeostasis through regulation of glucose and oxidative metabolism. Both PGC-1α expression and oxidative capacity are decreased in skeletal muscle of patients and animals undergoing atrophy, suggesting that PGC-1α participates in the regulation of muscle mass. PGC-1α gene expression is controlled by calcium- and cAMP-sensitive pathways. However, the mechanism regulating PGC-1α in skeletal muscle during atrophy remains unclear. Therefore, we examined the mechanism responsible for decreased PGC-1α expression using a rodent streptozotocin (STZ) model of chronic diabetes and atrophy. After 21days, the levels of PGC-1α protein and mRNA were decreased. We examined the activation state of CREB, a potent activator of PGC-1α transcription, and found that phospho-CREB was paradoxically high in muscle of STZ-rats, suggesting that the cAMP pathway was not involved in PGC-1α regulation. In contrast, expression of calcineurin (Cn), a calcium-dependent phosphatase, was suppressed in the same muscles. PGC-1α expression is regulated by two Cn substrates, MEF2 and NFATc. Therefore, we examined MEF2 and NFATc activity in muscles from STZ-rats. Target genes MRF4 and MCIP1.4 mRNAs were both significantly reduced, consistent with reduced Cn signaling. Moreover, levels of MRF4, MCIP1.4, and PGC-1α were also decreased in muscles of CnAα−/− and CnAβ−/− mice without diabetes indicating that decreased Cn signaling, rather than changes in other calcium- or cAMP-sensitive pathways, were responsible for decreased PGC-1α expression. These findings demonstrate that Cn activity is a major determinant of PGC-1α expression in skeletal muscle during diabetes and possibly other conditions associated with loss of muscle mass. [Copyright &y& Elsevier]

Abstract: Cavity formation is an important phenomenon in the underground coal gasification (UCG) process. In the early stages of cavity formation, only the combustion reaction is performed in order to stabilize the temperature field. In the present work, we study the formation of the combustion cavity and the effect of various design and operating parameters such as the distance between the wells, feed flow rate and operation time, on its evolution. This paper presents details of laboratory-scale experiments that demonstrate the shape and size of the combustion cavity, and their dependence on various parameters. Empirical correlations for the cavity volume and dimensions in various directions are developed, which indicate the strong effects of mass transport. Results from computational fluid dynamics (CFD), which map the velocity profiles in the cavity, support the experimental observations. [Copyright &y& Elsevier]

A numerical analysis of heat transfer in a heated horizontal duct is carried out to study the effect of surface radiation from duct inner walls on mixed convection heat transfer. The duct is differentially heated, wherein the opposing vertical walls are maintained at two specified isothermal temperatures, while the horizontal walls are perfectly insulated. Air enters the heated duct in a hydrodynamically fully developed condition, and steadily flows under laminar conditions while undergoing thermal development within the heated duct. For a set of specified temperature differences across the isothermal vertical walls, the heat transfer rate to the airflow is evaluated, and the fluid flow patterns are obtained for a range of flow rates, duct aspect ratios, and wall emissivities. Critically examining the fluid flow patterns and the characteristics of the hot wall Nusselt number, the significance of wall radiation effects on mixed convection heat transfer is identified and analysed in this study. It is found that the interaction of surface radiation and mixed convection influences the transport phenomena within heated ducts. [ABSTRACT FROM AUTHOR]

Abstract: A numerical study was conducted to investigate the fluid flow and heat transfer characteristics of a square microchannel with four longitudinal internal fins. Three-dimensional numerical simulations were performed on the microchannel with variable fin height ratio in the presence of a hydrodynamically developed, thermally developing laminar flow. Constant heat flux boundary conditions were assumed on the external walls of the square microchannel. Results of the average local Nusselt number distribution along the channel length were obtained as a function of the fin height ratio. The analysis was carried out for different fin heights and flow parameters. Interesting observations that provide more physical insight on this passive enhancement technique, and the existence of an optimum fin height are brought out in the present study. [Copyright &y& Elsevier]

Calcineurin is an important intracellular signaling molecule which can be inhibited by cyclosporin resulting in immune suppression and nephrotoxicity. Previously, we reported that homozygous loss of the a isoform of calcineurin impairs kidney development and function and mimics many features of cyclosporin nephrotoxicity. However, early lethality of null mice prevented further study of renal changes. Alternatively, we examined aged heterozygous (CnAα+/-) mice. In addition to renal dysfunction and inflammation, we find that CnAα+/- mice spontaneously develop tertiary lymphoid aggregates in the kidney, small intestine, liver, and lung. Lymphoid aggregates contain both T cells and B cells and exhibited organization suggestive of tertiary lymphoid organs (TLOs). Kidney function and TLO formation were highly correlated suggesting that this process may contribute to nephrotoxicity. Consistent with previous findings, transforming growth factor (TGF)-β is significantly increased in CnAα+/- mice. Neutralization of TGF-β attenuated TLO formation and improved kidney function. In conclusion, we report that haploinsufficiency of CnAα causes uregulation of TGF-β which contributes to chronic inflammation and formation of TLOs. While the process that leads to TLOs formation in transplant allografts is unknown, TLOs are associated with poor clinical prognosis. This study suggests that calcineurin inhibition itself may lead to TLO formation and that TGF-β may be a novel therapeutic target. [ABSTRACT FROM AUTHOR]

Compulsators are power sources of choice for use in electromagnetic launchers and railguns. These devices hold the promise of reducing unit costs of payload to orbit. In an earlier work, the author had calculated the current distribution in compulsator wires by considering the wire to be split into a finite number of separate wires. The present work develops an integral formulation of the problem of current distribution in compulsator wires which leads to an integrodifferential equation. Analytical solutions, including those for the integration constants, are obtained in closed form. The analytical solutions present a much clearer picture of the effect of various input parameters on the cross-sectional current distribution and point to ways in which the desired current density distribution can be achieved. Results are graphically presented and discussed, with particular reference to a 50-kJ compulsator in Bangalore. Finite-element analysis supports the results. [ABSTRACT FROM AUTHOR]

Abstract: Chirality is a key factor in the safety and efficacy of many drug products and thus the production of single enantiomers of drug intermediates has become increasingly important in the pharmaceuticals industry. There has been an increasing awareness of the enormous potential of microorganisms and enzymes derived therefrom for the transformation of synthetic chemicals with high chemo-, regio- and enatio-selectivities. In this article, biocatalytic processes are described for the synthesis of chiral intermediates for pharmaceuticals. [Copyright &y& Elsevier]

Johnson’s SB and the logit–logistic are four-parameter distribution models that may be obtained from the standard normal and logistic distributions by a four-parameter transformation. For relatively small data sets, such as diameter at breast height measurements obtained from typical sample plots, distribution models with four or less parameters have been found to be empirically adequate. However, in situations in which the distributions are complex, for example in mixed stands or when the stand has been thinned or when working with aggregated data, then distribution models with more shape parameters may prove to be necessary. By replacing the symmetric standard logistic distribution of the logit–logistic with a one-parameter “standard Richards” distribution and transforming by a five-parameter Richards function, we obtain a new six-parameter distribution model, the “Richit–Richards”. The Richit–Richards includes the “logit–Richards”, the “Richit–logistic”, and the logit–logistic as submodels. Maximum likelihood estimation is used to fit the model, and some problems in the maximum likelihood estimation of bounding parameters are discussed. An empirical case study of the Richit–Richards and its submodels is conducted on pooled diameter at breast height data from 107 sample plots of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.). It is found that the new models provide significantly better fits than the four-parameter logit–logistic for large data sets. [ABSTRACT FROM AUTHOR]

Abstract: Objective of the present study was to test the importance of tissue repair in the final outcome of S-(1,2-dichlorovinyl)-l-cysteine (DCVC)-induced nephrotoxicity using colchicine (CLC) intervention. Male Swiss Webster (SW) mice were administered a normally nonlethal dose of DCVC (30mg/kg, i.p.) on day 0 and CLC (2mg/kg, i.p.) at 42 and 66h after administration of DCVC. The mice were observed for mortality and various renal injury and repair parameters were studied during a time course of 0–14 days. Administration of 30mg DCVC/kg led to loss of renal architecture by day 1, which sustained until day 5, and regressed thereafter to reach normal architecture by day 10 resulting in 100% survival. Renal dysfunction as assessed by increases in plasma BUN and creatinine levels was concordant during this time course. Urinary volume increased significantly between days 10 and 14 with significant increases in urinary glucose concentrations on days 1–4. Calpain leakage increased from day 1 and remained so until day 5 before declining at later time points. In contrast, CLC intervention led to marked inhibition of S-phase DNA synthesis and 100% mortality by 120h. H&E sections of kidneys revealed loss of renal architecture on day 1 which progressively worsened from day 2 to 4. Polyuria and glycosuria were evident during the first 2 and 3 days, respectively. Calpain immunohistochemistry revealed progressive leakage of calpain in the extracellular space during 2–4 days which lead to increased renal injury as evident from significant increases in calpain specific breakdown products (CSBPs) of α-fodrin during the same period of time. The group of mice receiving 2mg CLC/kg alone showed a significant increase in urinary creatinine concentration on day 5. Neither the expression nor localization of aquaporin 1 was altered in any of the treatment groups. These results show that antimitotic intervention after DCVC-initiated renal injury leads to expansion and progression of that injury, which appears to be due to proteolytic destruction of neighboring cells mediated by calpain leaking out of necrosed renal tubular epithelial cells. [Copyright &y& Elsevier]

The reaction between Ta(OEt)5 and 1,1,3,3-tetramethyl-1,3-disiloxanediol, (HOSiMe2OSiMe2OH), leads to new siloxy complexes in which the dimeric nature of Ta(OEt)5 is maintained with both bridging ethoxide and disiloxanediolato bridges. With equal amounts of the reagents, two terminal OEt groups are replaced to form [Ta(OEt)2]2(μ-OEt)2(μ-OSiMe2OSiMe2O)2, 1, whereas with an excess of diol, the remaining terminal OEt groups are also replaced but with a trisiloxanediolato unit to form [Ta(OSiMe2OSiMe2OSiMe2O)]2(μ-OEt)2(μ-OSiMe2OSiMe2O)2, 2. Complexes 1 and 2 catalyze the transformation of HOSiMe2OSiMe2OH to polysiloxanes. Thermal treatment of 1 results in the formation of a 1:2 mixture of Ta2O5/SiO2; no new phases are observed. The molecular structures of 1 and 2 are confirmed by X-ray crystallography. [ABSTRACT FROM AUTHOR]

Abstract: Enantioselective asymmetric hydrolysis of (1α,2β,3α)-2-(benzyloxymethyl)-cyclopent-4-ene-1,3-diol diacetate 1 to the corresponding (+)-monoacetate 2 was carried out using lipase PS-30 from Pseudomonas cepacia or pancreatin. A reaction yield of 85M% with an enantiomeric excess (ee) of 98% was obtained. Using pancreatin, a reaction yield of 75M% with an ee of 98.5% was obtained. Asymmetric acetylation of (1α,2β,3α)-2-(benzyloxymethyl)-cyclopent-4-ene-1,3-diol 3 to the corresponding (−)-monoacetate 4 was carried out using lipase PS-30 with isopropenyl acetate as the acylating agent. A reaction yield of 80M% with an ee of 98% was obtained for (−)-monoacetate 4. [Copyright &y& Elsevier]

Electrospray ionization (ESI) quadrupole ion trap mass spectrometry (QIT-MS) and collisionally activated dissociation (CAD) were used to evaluate the rare-earth binding properties of two hydrophobic carbamoylmethylphosphine oxide (CMPO) ligands, the normal bidentate variety, (t-BuC6H4)2P(O)CH2C(O)N(i-Bu)2 (A), a new potentially tridentate extractant, (t-BuC6H4)2P(O)CH[CH2C(O)N(i-Bu)2]C(O)N(i-Bu)2 (B), and tributyl phosphate. The mass spectral results obtained from analysis of 1% HNO3/methanol solution containing the ligands and dissolved lanthanide salts reveal that the favorable stoichiometries of the ligand/metal/nitrate complexes are 2:1:2 for the bidentate ligand A, 1:1:2 for the tridentate ligand B, and 3:1:2 for the monodentate tributyl phosphate. These observed stoichiometries correlate with the number of available binding sites on each ligand as well as with potential steric effects. Energy-variable collisionally activated dissociation experiments showed that for the 2:1:2 complexes involving ligand A or B, as the ionic radius of the bound metal decreased, the removal of nitric acid required less energy and resulted in less extensive spontaneous solvent coordination. This experimental trend suggests that, as the ionic radius of the lanthanide ion decreases, a pair of the carbamoylmethylphosphine ligands is able to more completely solvate the bound metal ion thereby weakening the nitrate-metal interaction. [ABSTRACT FROM AUTHOR]

The chiral intermediate (S)-1-(2′-bromo-4′-fluoro phenyl)ethanol 2 was prepared by the enantioselective microbial reduction of 2-bromo-4-fluoro acetophenone 1. Organisms from genus Candida, Hansenula, Pichia, Rhodotorula, Saccharomyces, Sphingomonas and Baker''s yeast reduced 1 to 2 in >90% yield and 99% enantiomeric excess (ee). In an alternative approach, the enantioselective microbial reductions of methyl, ethyl, and tert-butyl 4-(2′-acetyl-5′-fluorophenyl) butanoates 3, 5, and 7, respectively, were demonstrated using strains of Candida and Pichia. Reaction yields of 40–53% and ee''s of 90–99% were obtained for the corresponding (S)-hydroxy esters 4, 6, and 8. The reductase, which catalyzed the enantioselective reduction of ketoesters was purified to homogeneity from cell extracts of Pichia methanolica SC 13825. It was cloned and expressed in Escherichia coli with recombinant cultures used for the enantioselective reduction of keto methyl ester 3 to the corresponding (S)-hydroxy methyl ester 4. On a preparative scale, a reaction yield of 98% and an ee of 99% was obtained. [Copyright &y& Elsevier]

The chiral intermediate (3R)-cis-3-acetyloxy-4-(1,1-dimethylethyl)-2-azetidinone 2 was prepared for the semi-synthesis of the new taxane 5, an orally active anticancer compound. The enantioselective enzymatic hydrolysis of cis-3-acetyloxy-4-(1,1-dimethylethyl)-2-azetidinone 1 to the corresponding undesired (S)-alcohol 3 and unreacted desired 2 was carried out using immobilized lipase PS-30 or BMS lipase. Reaction yields of >48% and enantiomeric excesses of >99% were obtained for the desired 2. Acetoxy β-lactam 2 was converted to hydroxy β-lactam 4 for use in the semisynthesis of 5. [Copyright &y& Elsevier]