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The purpose of this research was to improve the safety and performance by reducing the weight of the on-road vehicles with the utilization of reinforced sandwich composite material in automotive doors and panels. By this research conducted, the vehicle guarantees safety, since the dominant force works on bumpers and doors at the moment of impact and the possibility that sandwich panels will be put within the passenger seat, meaning that the safety of the user will be improved and the impact will be maximized. From the results, mechanical vibrations frequencies of Nomex, polyurethane and polypropylene honeycomb core structures showed 10% deviation when compared with the experimental results. With the implementation of the proposed sandwich panel in various automotive components, the vehicle weight will gradually be reduced, which ensures that the vehicles performance improves naturally.

The objective of this work was to produce and use green pea pod lignin for improving the thermal stability, flammability, and creep resistance of pineapple fibre-reinforced epoxy composite. The lignin macromolecules are derived from waste green pea pods via thermo-chemical process and used as reinforcement. The composites were made using the compression moulding method followed by post curing at 120°C. The prepared composites are then machined for testing according to ASTM standards. The results of this research demonstrate that the decomposition temperature of the composite known as EF is improved by the incorporation of pineapple woven mats by a volume of 40%. Comparing to all the composite designations, the EFL3 offers the least loss of weight, the highest decomposition temperature (approximately 420°C), the highest storage modulus (about 7.5 GPa), and the lowest loss tangent (0.6). Accordingly, the EFL3 composite designation has been reported to have the lowest combustion rate of 5.88 mm/min and the highest DSC value of 0.6 mW/mg. However, the creep strain is reduced when adding lignin by 0.5, 1.0, and 2.0 vol. %. These eco-friendly waste converted green pea pod lignin strengthened pineapple fibre-epoxy composites could be used in high thermal applications including automotive insulation panels and domestic infrastructure.

In this paper, we defined and studied the monotonicity of homogeneous function of the type N[a, b; p; q; r; [alpha], [mu]]=[[{[[[a.sup.p] + [mu][M.sub.r]([a.sup.p], [b.sup.p]) + [alpha][b.sup.p]]/[[a.sup.q] + [mu][M.sub.r]([a.sup.q], [b.sup.q]) + [alpha][b.sup.p]]]}].sup.[1/[p - q]]].. Further, established some valuable inequalities involving various means and some well known means are deduced as the particular cases of this homogeneous function. Keywords and Phrases: Inequality, Power exponential mean, Weighted and Contra harmonic mean., 1. Introduction and Definition In (1), G. Toader and S. Toader briefly explored the work on Arithmetic mean, Geometric mean and Greek means. V. Lokesha and et al. are studied [...]

ABSTRACTThe main fuel for transport is diesel. It adds to the success of overall economy, as it is widely used due to its high efficiency in combustion, versatility, unwavering quality and cost-effectiveness. One of the major sources of air pollution on the Earth is emission from diesel engines. Over the years, the need for biofuels has enabled Momordica charantia seed oil to become biodiesels. Momordica charantia seed oil having low calorific value than other biodiesels made it an alternative for diesel which shows lower emission and improvement in performance characteristics. In this exploration work, to study the emission and performance characteristics of biodiesel, four blends of Momordica charantia seed oil with cerium oxide added substance are investigated. The results showed that B30 (69% diesel, 30% biodiesel and 1% cerium oxide) performs better than different blends.

ABSTRACTMany litres of used cooking oils from the food preparation were just throw away as a Waste Cooking Oil (WCO) and it will pollute the environment. The best way of utilising it by converting WCO to biodiesel. In this research, the performance and emission characteristics of four-stroke diesel engine have been experimentally investigated for the waste cooking oil emulsion and it is compared with conventional diesel. In addition effect of 50 ppm of aluminium oxide nanoparticle to the waste cooking oil, the emulsion is also studied. Performance tests were carried out in a constant speed single cylinder diesel engine fuelled with diesel, waste cooking oil emulsion and waste cooking oil nanoemulsions. The test results show that significant improvement in brake thermal efficiency and reduced specific fuel consumption and oxides of nitrogen for waste cooking oil nanoemulsion as compared to the waste cooking oil emulsion.

ABSTRACTExperimental studies indicate that the maximum stress acted on the top portion of the piston and stress concentration is also the main cause of fatigue failure. This article discusses the improvement on the piston to endure high structural and thermal stresses and to moderate stress concentration the top portion of the piston. An aluminum alloy piston can be replaced by a carbon-carbon piston which has low thermal stress in same working condition. In this paper, thermal analysis of carbon-carbon composite material on commercial vehicle diesel engine piston was studied and the results were compared with aluminum alloy piston for maximum stress.

We have used transient absorption spectroscopy in the UV–visible and X-ray regions to characterize the excited state of CarH, a protein photoreceptor that uses a form of B12, adenosylcobalamin (AdoCbl), to sense light. With visible excitation, a nanosecond-lifetime photoactive excited state is formed with unit quantum yield. The time-resolved X-ray absorption near edge structure difference spectrum of this state demonstrates that the excited state of AdoCbl in CarH undergoes only modest structural expansion around the central cobalt, a behavior similar to that observed for methylcobalamin rather than for AdoCbl free in solution. We propose a new mechanism for CarH photoreactivity involving formation of a triplet excited state. This allows the sensor to operate with high quantum efficiency and without formation of potentially dangerous side products. By stabilizing the excited electronic state, CarH controls reactivity of AdoCbl and enables slow reactions that yield nonreactive products and bypass bond homolysis and reactive radical species formation.

ABSTRACTIn the agriculture and transportation sector, many bio-seed based biofuels have exposed to be a better replacement for fuels derivative from fossil fuels. In the Indian context, due to the energy needs, agricultural growth, surrounding degradation and rural development these biofuels have achieved an acknowledgment as an alternative. Biofuels derived from the bio seeds such as rubber seed oil, cottonseed oil, jatropha and rapeseed oil etc. can hold the carbon emissions from vehicles in an efficient and economical method. In this research paper, an attempt has been made with blends from bio-seed based Sapindus seed oil with nano additive as an alternative for diesel. Its performance and emission characteristics were investigated on the constant speed single cylinder CI engine and results were compared.

This research demonstrates a process to convert polypropylene pyrolysis oil (PPO) into diesel. The hydroprocessing of PPO (HPPO-B) utilizing a Ni–Mo/Lap bimetal catalyst has been attempted in this study. Hydroprocessing of plastic pyrolysis oil had been attempted earlier, but the hydroprocessing of PPO utilizing a bimetal catalyst and the corresponding validation suites consisting of physicochemical tests, composition comparison with diesel, and diesel engine trials have not yet been reported. The physicochemical properties of the produced HPPO-B matched EN590 standard (European diesel standards) requirements. The hydroprocess conditions (70 bar and 350 °C) and the synthesized Ni–Mo/modified Lap catalyst have been responsible for producing n-alkanes, isoalkanes, and aromatics in proportions that gave a 95% match with diesel. Diesel engine combustion and emissions of HPPO-B matched those of diesel. HPPO-B provides the opportunity to utilize plastic solid waste (PSW) as a transport fuel. The results of HPPO-B inspire and encourage pursuance of the hydroprocess path for protecting the environment from hazardous plastic solid waste (PSW).

This paper of finite-time synchronization for Markovian jumping complex dynamical frameworks with hybrid couplings is studied. A state feedback control is planned for finite-time synchronization of complex frameworks is presented. Sufficient synchronization criteria are proposed in light of the Lyapunov stability theory. A sensible Lyapunov-Krasovskii functional (LKF) is worked with Kronecker products. The desired state feedback controller can be refined by comprehending a plan of linear matrix inequalities (LMIs). Numerical simulation of complex frameworks demonstrates the comprehensiveness and the ampleness of the proposed method.

In this paper, we research the Schur convexity, Schur geometric convexity and Schur harmonic convexity of the Bonferroni harmonic mean. Some inequalities identified with the Bonferroni harmonic mean are set up to represent the utilizations of the acquired outcomes.

ABSTRACTDiesel is the main source of world transportation due to higher combustion efficiency, compliance, consistency and cost-economy. It is also a major contributor to the world prosperity since it is used extensively. Diesel engine’s emissions are the serious hazard to the world environment and it is measured to be the major causes of air pollution. The demand in biofuels for years created a scope for aloe vera into biodiesels. Aloe vera, having higher calorific value vnthan other plant sources used as biodiesels, enhanced us in making another alternative biodiesel, which has lesser emissions and better performance. In this research work, four biodiesel blends from aloe vera oil with cerium oxide additive are explored for their performance and emission characteristics. The results proved B30 (30% biodiesel, 68% diesel and 1% cerium oxide) gives good performance when compared to other blends.

Alcohol consumption has been linked to over 200 diseases and is responsible for over 5% of the global disease burden. Well-known genetic variants in alcohol metabolizing genes, for example, ALDH2 and ADH1B, are strongly associated with alcohol consumption but have limited impact in European populations where they are found at low frequency. We performed a genome-wide association study (GWAS) of self-reported alcohol consumption in 112 117 individuals in the UK Biobank (UKB) sample of white British individuals. We report significant genome-wide associations at 14 loci. These include single-nucleotide polymorphisms (SNPs) in alcohol metabolizing genes (ADH1B/ADH1C/ADH5) and two loci in KLB, a gene recently associated with alcohol consumption. We also identify SNPs at novel loci including GCKR, CADM2 and FAM69C. Gene-based analyses found significant associations with genes implicated in the neurobiology of substance use (DRD2, PDE4B). GCTA analyses found a significant SNP-based heritability of self-reported alcohol consumption of 13% (se=0.01). Sex-specific analyses found largely overlapping GWAS loci and the genetic correlation (rG) between male and female alcohol consumption was 0.90 (s.e.=0.09, P-value=7.16 × 10−23). Using LD score regression, genetic overlap was found between alcohol consumption and years of schooling (rG=0.18, s.e.=0.03), high-density lipoprotein cholesterol (rG=0.28, s.e.=0.05), smoking (rG=0.40, s.e.=0.06) and various anthropometric traits (for example, overweight, rG=−0.19, s.e.=0.05). This study replicates the association between alcohol consumption and alcohol metabolizing genes and KLB, and identifies novel gene associations that should be the focus of future studies investigating the neurobiology of alcohol consumption.

Albuminuria is associated with increased risk of cardiovascular disease and target organ damage in patients with diabetes mellitus. In nondiabetic hypertensive patients, the threshold at which microalbuminuria (MAU) increases risk is unclear and there is evidence that cardiovascular risk may be increased in individuals with MAU levels lower than the usual recommended screening thresholds. We compared two definitions of MAU (on the basis of three early morning urine samples) in a cohort of hypertensive patients attending two specialist clinics in Scotland: conventional (MAU(C)) albumin-to-creatinine ratio (ACR) >2.5–25 mg mmol−1in males or >3.5–25 mg mmol−1in females; and low-grade (MAU(L)) ACR 1.2–2.5 in males or 1.7–3.5 mg mmol−1in females. Of the 1059 subjects screened, 786 (74%) were nondiabetic, with estimated glomerular filtration rate ⩾30 ml min−1per 1.73 m2and without gross proteinuria (low-risk subset). The average age was 58±15 years, body mass index 30±6 kg m−2and 46% were males. The prevalence of MAU(C) was 11% and 9.5% in the overall and low-risk subset, respectively, whereas MAU(L) prevalence was 11.1% and 10% respectively. The prevalence of cardiovascular disease was higher (24%) with albuminuria (both MAU(C) and MAU(L)) compared with 14% among those without albuminuria. The use of MAU(L) doubled the number of hypertensive subjects with increased cardiovascular risk who can be targeted for more rigorous risk reduction strategies. Consideration should be given to reducing the current threshold for MAU.

Cognitive impairment is common among individuals diagnosed with autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). It has been suggested that some aspects of intelligence are preserved or even superior in people with ASD compared with controls, but consistent evidence is lacking. Few studies have examined the genetic overlap between cognitive ability and ASD/ADHD. The aim of this study was to examine the polygenic overlap between ASD/ADHD and cognitive ability in individuals from the general population. Polygenic risk for ADHD and ASD was calculated from genome-wide association studies of ASD and ADHD conducted by the Psychiatric Genetics Consortium. Risk scores were created in three independent cohorts: Generation Scotland Scottish Family Health Study (GS:SFHS) (n=9863), the Lothian Birth Cohorts 1936 and 1921 (n=1522), and the Brisbane Adolescent Twin Sample (BATS) (n=921). We report that polygenic risk for ASD is positively correlated with general cognitive ability (beta=0.07, P=6 × 10−7, r2=0.003), logical memory and verbal intelligence in GS:SFHS. This was replicated in BATS as a positive association with full-scale intelligent quotient (IQ) (beta=0.07, P=0.03, r2=0.005). We did not find consistent evidence that polygenic risk for ADHD was associated with cognitive function; however, a negative correlation with IQ at age 11 years (beta=−0.08, Z=−3.3, P=0.001) was observed in the Lothian Birth Cohorts. These findings are in individuals from the general population, suggesting that the relationship between genetic risk for ASD and intelligence is partly independent of clinical state. These data suggest that common genetic variation relevant for ASD influences general cognitive ability.

The design of gears is critical for smooth running of any mechanism, automobile and machinery. Gear drive design starts with the need of optimizing the gear thickness, module, number of teeth etc., this creates huge challenges to a designer. Optimization algorithms are more flexible and gaining importance in engineering design problems, because of the accessibility and affordability of today’s mechanical field. A population based heuristic algorithm offers well-organized ways of creating and comparing a novel design solution in order to complete an optimal design. In this paper, a new artificial immune system based algorithm proposed as Modified Artificial Immune System (MAIS) algorithm is used to optimize a gear design problem. The results are compared with an existing design.

The bottom-up colloidal synthesis of photonic band gap (PBG) materials or photonic crystals (PC) has attracted considerable interest as compared to so-called top-down lithographic approaches due to the simple processing steps involved and the prospect of the economically viable production of complex 3-dimensional optical materials from simple colloidal particles. To date self-assembly techniques constitute the most popular approach to fabricate 3D photonic crystals from colloidal particle suspensions. Based on the natural tendency of monodisperse colloidal particles to organise into ordered arrays, this method represent the best option due to the ease of fabrication, ability to produce larger area samples and cost. Here we report on the fabrication of long range three-dimensional (3D) ordered poly (methyl methacrylate) (PMMA)-silica PC structures and the subsequent fabrication of robust silica inverse opals using self-assembly methods. The optical properties of these materials are described and discussed in terms of potential applications of these materials.

In a perspective of stable industrial development to manufacture added consistent and economical industrial product, gears are ever more focus to requirements in terms of power capability, efficiency and compactness etc. In order to increase the performance factors of gears such as transmission capacity, efficiency, gear life, etc. is a difficult criteria for a design engineers as these are all progress in a conflicting behavior. This paper deals with the multi-objective optimization of spur gear drive design with two contradictory objective functions such as maximization of power transmission and minimization of volume of the gear drive. These objectives are approached by an optimization technique based on a Sheep Flocks Heredity Model Algorithm (SFHM) with design constraints like stress, center distance etc. A spur gear problem is solved with traditional trial method and results are compared with proposed algorithm.

In several multimedia applications, image and video coding plays a significant role. In many applications, sceneries such as broadcast services over satellite and terrestrial channels, digital video storage, wires and wireless conversational services and digital video communication are used. It is not possible to store full digital video without processing. Video compression reduces the data used to represent digital video images and is a combination of spatial image compression and temporal motion compensation. The main aim of our research is to develop an efficient video compression system. The proposed system consists of three steps. At first, wavelet decomposition is applied to the I–frame and the resulting coefficients are quantised using the listless SPECK (LSK) algorithm. In the next step, motion estimation is done using adaptive rood search with the spatio–temporal correlation method (ARS–ST) and it calculates the distance between the P–frame and I–frame blocks. In the final step, the difference between the original and the predicted P–frame is evaluated and is known as residual. To produce good quality predictive frames, this residual is transmitted along with motion vectors (MVs) and to decrease its size, it is coded using LSK. The proposed video compression technique uses different videos for assessment and by determining the PSNR values, compression efficiency is estimated. By comparing the proposed system with existing systems, it is seen that our system effectively compresses videos with remarkable PSNR measurements.

he major problem that deals with practical engineers is the mechanical design and creativeness. Mechanical design can be defined as the choice of materials and geometry, which satisfies, specified functional requirements of that design. A good design has to minimize the most significant adverse result and to maximize the most significant desirable result. An evolutionary algorithm offers efficient ways of creating and comparing a new design solution in order to complete an optimal design. In this paper a type of Genetic Algorithm, Real Coded Genetic Algorithm (RCGA) is used to optimize the design of helical gear pair and a combined objective function with maximizes the Power, Efficiency and minimizes the overall Weight, Centre distance. The performance of the proposed algorithms is validated through LINGO Software and the comparative results are analyzed.

In this paper, an attempt has been made to optimise bevel gear pair design using a non-linear programming optimising software LINGO and meta-heuristics such as real coded genetic algorithm, ant colony optimisation and particle swarm optimisation algorithms. A combined objective function which maximises the power, efficiency and minimises the overall weight, centre distance has been considered in this model. The efficiency of the proposed algorithms is validated through gear design problems and the comparative results are studied.

The planning and execution of clinical trials utilizing response-adaptive randomization is logistically complex. While a standardized approach to such designs is worthwhile, there are also unique challenges with each trial. Three detailed case studies are provided to illustrate the types of logistical issues that arise, as well as the decision problems coming before the data monitoring committees. Several lessons learned from these case studies are presented. These range from consideration of more extreme scenarios for trial simulation during the planning stage to formal establishment of an executive steering committee to facilitate the decision process (even for learn-phase trials).

The planning and execution of clinical trials utilizing response-adaptive allocation involves complexities beyond those encountered in the planning and execution of more traditional trial designs. How the adaptive design will optimize the drug development process must be clearly defined; an appropriate endpoint must be selected to drive the adaptive design engine; and steps must be taken to ensure that the data required for adaptive decision making will be available in a timely fashion during the trial. Trial simulations are essential during the planning stage to develop appropriate decision rules and the response-adaptive allocation algorithm, Structures such as data monitoring committees and independent statistical centers help to ensure the validity and integrity of the trial while facilitating decision making during the trial.

ABSTRACTIntroduction:This research compares the efficacy and safety of desvenlafaxine (administered as desvenlafaxine succinate) versus placebo in treating major depressive disorder.Methods:In this randomized, double-blind study, outpatients with major depressive disorder =18 years of age received desvenlafaxine 200–400 mg/day or placebo for 8 weeks. Efficacy endpoints included (primary) change in 17-item Hamilton Rating Scale for Depression score at the final evaluation (last observation carried forward, analysis of covariance) and (secondary) Clinical Global Impressions—Improvement and—Severity of Illness scales.Results:The difference between desvenlafaxine (n=117) and placebo (n=118) on the primary endpoint was not significant (-9.1 vs -7.5, P=.078). Week 8 observed cases (desvenlafaxine, n=80; placebo, n=94) results were significant (-10.7 vs -7.9, P=.008). Differences at the final evaluation (last observation carried forward) were significant for Clinical Global Impressions—Improvement (2.9 vs 2.5, P=.037) and Clinical Global Impressions—Severity of Illness (-1.9 vs -1.2, P=.041). Discontinuation rates due to adverse events (AEs) were 12% and 3% for desvenlafaxine and placebo, respectively (P=.008). The most frequently reported AE associated with desvenlafaxine was nausea (36% vs 9% [placebo]).Conclusion:In this study, the primary analysis did not show significant differences between desvenlafaxine and placebo; discontinuations due to AEs associated with the desvenlafaxine dose range may have contributed to the lack of statistical separation.

Background: An accurate, precise and robust analytical method was developed for the impurity profiling in the metformin hydrochloride and teneligliptin hydrobromide hydrate tablet. The gradient was optimized for better separation of impurities by using BDS Hypersil C18 250 × 4.6 mm, 5µ column operated at 35 °C. The octane sulfonic acid and phosphate buffer with triethylamine at pH 3.0 were used as mobile phase A, and acetonitrile was used as mobile phase B. The mobile phase was pumped at 1.0 mL/min. The gradient was optimized for better resolution, and the chromatogram was monitored at 210 nm. Results: The % recovery of teneligliptin and metformin HCL observed was above 90% from LOQ level to 150%. The correlation coefficient r2was 0.999 for metformin HCl, teneligliptin, melamine, cyanocobalamin, teneligliptin impurity A and 0.998 for teneligliptin impurity B. The method was found unaffected by change in method variance during the robustness study. During the stress study with acid, base, peroxide and temperature, maximum degradation was observed with peroxide indicating the sensitivity of the molecule toward oxidative stress. Conclusions: The developed method is precise, accurate, robust and linear and hence can be routinely used for the related substance analysis of metformin hydrochloride and teneligliptin hydrobromide hydrate tablet in the quality control laboratory at manufacturing site during the commercial manufacturing.

Background: Regional abnormalities in myocardial systolic function can be detected with myocardial strain measurements derived from Doppler tissue echocardiography. We studied longitudinal strain measurements in patients with evidence of myocardial infarction by cardiac magnetic resonance imaging to determine whether end-systolic strain could identify the severity of the infarction. Methods: A total of 20 patients with chronic myocardial infarctions and 10 healthy volunteers underwent 2-dimensional echocardiography and cardiac magnetic resonance with delayed gadolinium (Gd) gadopentetate dimeglumine (DTPA) contrast hyperenhancement. Delayed Gd hyperenhancement was graded using the following scale: 0 = none, 1 = less than 25%, 2 = 26% to 50%, 3 = 51% to 75%, and 4 = greater than 75%. Results: There was a progressive decrease in peak systolic strain in the infarct segments as the transmural extent of infarction increased. When compared with the peak systolic strain in remote segments without evidence of infarction (-19.7 +/- 0.9), the strain was significantly lower in segments with greater than 25% Gd hyperenhancement (grade 2, -14.8 +/- 1.1, P = .001; grade 3, -12.9 +/- 2.1, P = .001; grade 4, -9.1 +/- 2.0, P < .001). Conclusions: In patients with chronic myocardial infarctions, strain measurements with echocardiography show a graded response of decreasing regional strain in segments with increasing transmural extent of infarction defined by Gd hyperenhancement.

The combined serotonin–norepinephrine reuptake inhibitor, venlafaxine XR, has demonstrated significant response and remission in patients diagnosed with depression when measured with the Hamilton Depression Rating Scale (HAM-D). This pooled analysis of data from five studies compared the sustained remission of depressive symptoms in patients treated with venlafaxine XR, the selective serotonin reuptake inhibitors (SSRIs) fluoxetine or paroxetine, or placebo. Data from 1391 subjects enrolled in five active and placebo-controlled studies who met the DSM-III-R or DSM-IV criteria for major depressive disorder were analysed. Three treatment groups were compared venlafaxine XR (n560), fluoxetineparoxetine (n298) and placebo (n496). Mean treatment duration was 8 weeks. Responders were defined as those patients whose HAM-D-21 score decreased by ≥50 from baseline. Remission was defined as a HAM-D-17 score ≤7. Sustained remission was defined as maintenance of remission through week 8 or the end of treatment (if before week 8) and for ≥2 weeks. Between-group rate comparisons in outcome measures were carried out using Fisher's exact and log-rank tests. Venlafaxine XR produced significantly higher rates of sustained remission in depressed patients compared to fluoxetineparoxetine or placebo over this 8-week treatment period. As early as week 2, a significantly greater proportion of patients treated with venlafaxine achieved improved depression scores (remission and response). A significantly greater rate of remission and sustained remission occurred with venlafaxine compared to placebo. Remission was achieved earlier with venlafaxine and lasted throughout the remainder of the study. These results demonstrate that venlafaxine XR is more effective than fluoxetineparoxetine for sustaining remission of depressive symptoms.

With the tremendous advances in hand-held computing and communication capabilities, rapid proliferation of mobile devices, and decreasing device costs, we are seeing a growth in mobile e-business in various consumer and business markets. In this paper, we present a novel architecture and framework for end-to-end mobile e-business applications (e.g., point of sales). The architecture takes into consideration disconnection, application context, synchronization, transactions and failure recovery modes to provide mobile users with seamless and transparent access to business transactions and business-context specific data. In our architecture, we consider a novel business process design based on state-machines and event management to handle disconnection, resource limitations and failures. We designed, implemented and deployed a system for mobile e-business on clients (e.g., PDAs and PocketPCs) integrated with private exchanges and sell-side servers. The state-machine model with failure recovery mechanisms enables handling of one-to-many and many-to-one disconnections in large mobile e-business environments. The e-business framework on mobile clients is implemented based on J2ME, Webservices, and open XML standards. A detailed performance study of commerce transactions was done on different mobile client devices with diverse computing, memory and storage capabilities. We compare the performance of a purchasing application and the middleware on various devices such as PDAs and Laptops. We demonstrated that for small devices with limited capability the performance is reasonable. For devices with more computing capability, the response time is excellent.

A beamline to carry out photoabsorption and fluorescence experiments using INDUS-1 synchrotron radiation source has been recently commissioned at the Centre for Advanced Technology, Indore India. The optical system for the beamline consists of a pre-focusing toroidal mirror, an indigenously developed one meter Seya-Namioka monochromator and a post-focusing toroidal mirror to cover the wavelength range of 500Å–2000Å. An experimental chamber for performing VUV excited fluorescence on solid samples is coupled to the beamline. A quarter meter gas cell has also been fitted with the experimental station. In this paper, we have presented the salient features of the beamline and the recorded photoabsorption spectra of benzene and benzene-d6.

This article reports the results from a study conducted to characterize the frictional properties of friction spun yarns. The aim of the study was to obtain data on the surface mechanical properties of a variety of friction spun yarns. The study was essential as the surface mechanical properties influence the fabric formation, bonding strength, and high-performance properties of yarns. The yarns used in the study were made from different fibers and were spun at different speeds. The capstan method was used to obtain the friction force values between the yarns and a glass cylindrical rod. The experiment was conducted at different tensions. The results indicate that the friction of friction spun yarns are influenced by different factors such as the type of fiber and tensions applied. The results obtained help to understand the surface mechanical properties of high-performance yarns and their influence on the performance characteristics of friction spun yarns. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2450–2454, 2003

The light-inducible carBoperon encodes all but one of the structural genes for carotenogenesis inMyxococcus xanthus. It is transcriptionally controlled by two proteins expressed from two unlinked genetic loci: CarS from the light-inducible carQRSoperon, and CarA from the light-independent carAoperon. CarA represses transcription from the carBpromoter (PB) in the dark, and CarS counteracts this on illumination. The CarA sequence revealed a helix-turn-helix DNA-binding motif of the type found in bacterial MerR transcriptional factors, whereas CarS contains no known DNA-binding motif. Here, we examine the molecular interplay between CarA and CarS. We demonstrate the following. (i) Whereas CarS exhibits no DNA bindingin vitro, CarA binds specifically to a region encompassing PBto form at least two distinct complexes. (ii) A palindrome located between positions −46 and −63 relative to the transcription start point is essential but not sufficient for the formation of the two CarA-DNA complexes observed. (iii) CarS abrogates the specific DNA binding of CarA. CarA is therefore a repressor and CarS an antirepressor. (iv) CarS physically interacts with CarA; thus, the functional interaction between them is mediated by protein-protein interactions.

Myxococcus xanthustranscriptional factor CarD participates in carotenogenesis and fruiting body formation. It is the only reported prokaryotic protein having adjacent “AT-hook” DNA-binding and acidic regions characteristic of eukaryotic high mobility group A (HMGA) proteins. The latter are small, unstructured, nonhistone nuclear proteins that function as architectural factors to remodel DNA and chromatin structure and modulate various DNA binding activities. We find CarD to be predominantly dimeric with two stable domains: (a) an N-terminal domain of defined secondary and tertiary structure which is absent in eukaryotic HMGA proteins; (b) a C-terminal domain formed by the acidic and AT-hook segments and lacking defined structure. CarD, like HMGA proteins, binds specifically to the minor-groove of AT-rich DNA present in two appropriately spaced tracts. As in HMGA proteins, casein kinase II can phosphorylate the CarD acidic region, and this dramatically decreases the DNA binding affinity of CarD. The acidic region, in addition to modulating DNA binding, confers structural stability to CarD. We discuss how the structural and functional plasticity arising from domain organization in CarD could be linked to its role as a general transcriptional factor in M. xanthus.

We report the synthesis of the single enantiomers of permanently charged dihydropyridine derivatives (DHPs with alkyl linker lengths of two and eight carbon atoms) and their activities on cardiac and neuronal L-type calcium channels. Permanently charged chiral 1,4-dihydropyridines and methyl (ω-trimethylalkylammonium) 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-3,5-pyridinedicarboxylate iodides were synthesized in high optical purities from (R)-(−) and (S)-(+)-1,4-dihydro-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-3-pyridinecarboxylic acid, obtained by resolution of racemic 1,4-dihydro-2,6-dimethyl-5-methoxycarbonyl-4-(3-nitrophenyl)-3-pyridinecarboxylic acid. Competition binding experiments with radioligand [³H]-(+)-PN200-110 and the block of whole cell barium currents through L-type calcium channels in GH4C1 cells show that the compounds with the eight-carbon alkyl linker optimally block the L-type Ca²⁺ channels, and that the S-enantiomer is more potent than the R-enantiomer.

Bis-tetraazamacrocycles such as the bicyclam AMD3100 are a class of potent and selective anti-HIV-1 and HIV-2 agents that inhibit virus replication by binding to the chemokine receptor CXCR4, the co-receptor for entry of X4 viruses. With the aim of optimizing the anti-HIV-1 and HIV-2 activity of bis-azamacrocycles, a series of analogues were synthesized which contain neutral heteroatom (oxygen, sulfur) or heteroaromatic (of lower pKa than a secondary amine) replacements for the amino groups of AMD3100. The introduction of one or more heteroatoms such as oxygen or sulfur into the macrocyclic ring of p-phenylenebis(methylene)-linked dimers (to give N3X or N2X2 bis-macrocycles) gave analogues with substantially reduced anti-HIV-1 (IIIB) and anti-HIV-2 (ROD) potency. In addition, the bis-sulfur analogue was also markedly more cytotoxic to MT-4 cells. However, bis-tetraazamacrocycles featuring a single pyridine group incorporated within the macrocyclic framework exhibited anti-HIV-1 and HIV-2 potency comparable to that of their saturated, aliphatic counterparts. The p-phenylenebis(methylene)-linked dimer of the py[14]aneN4 macrocycle inhibited HIV-1 replication at a 50% effective concentration (EC50) of 0.5 μM while remaining nontoxic to MT-4 cells at concentrations approaching 200 μM. A series of analogues containing macrocyclic heteroaromatic groups of varying pKa were also synthesized, and their ability to inhibit HIV replication was evaluated. Replacing the pyridine moiety of the py[14]aneN4 macrocyclic ring with pyrazine or pyridine groups substituted in the 4-position (with electron-withdrawing or -donating groups) either reduced antiviral potency or increased cytotoxicity to MT-4 cells. Finally, we synthesized a series of analogues in which the ring size of the bis-pyridyl macrocycles was varied between 12 and 16 members per ring including the py[iso-14]aneN4 ring system, an isomer of the py[14]aneN4 macrocycle. The p-phenylenebis(methylene)-linked dimer of the py[iso-14]aneN4 (AMD3329) displayed the highest antiviral activity of the bis-azamacrocyclic analogues reported to date, exhibiting EC50's against the cytopathic effects of HIV-1 and HIV-2 replication of 0.8 and 1.6 nM, respectively, that is, about 3−5-fold lower than the EC50 of AMD3100. AMD3329 also inhibited the binding of a specific CXCR4 mAb and the Ca²⁺ flux induced by SDF-1α, the natural ligand for CXCR4, more potently than AMD3100. Furthermore, AMD3329 also interfered with virus-induced syncytium formation at an EC50 of 12 nM.

The thin‐walled curved beam equations are formulated using the principle of virtual work. The Euler Lagrange equilibrium equations and the associated static and kinematic boundary conditions thus obtained are compared with Vlasov, Chai Hang Yoo, and Papengelis and Trahair. In and out of plane buckling of curved beam problems are solved and compared to published results.

Detailed calculations of the mobility in

1. An inhibitor of cytoplasmic guanine deaminase of rat liver was isolated from liver ‘heavy mitochondrial’ fraction after freezing and thawing and treatment with Triton X-100. 2. Submitochondrial fractionation revealed that the inhibitor was localized in the outer-membrane fraction. 3. The method of purification of inhibitor, involving precipitation with (NH4)2SO4 and chromatography on DEAE-cellulose, its precipitability by trichloroacetic acid and the pattern of absorption in the u.v. indicated that the inhibitor was a protein. In confirmation, tryptic digestion of the isolated material resulted in destruction of the inhibitor activity. The inhibitor was stable to acid, but labile to heat. 4. The isolated inhibitor required phosphatidylcholine (lecithin) for activity. Phosphatidylcholine also partially protected the inhibitor against heat inactivation. 5. When detergent treatment was omitted, the inhibitor activity of frozen mitochondria was precipitated by (NH4)2SO4 in a fully active form without supplementation with phosphatidylcholine, indicating that Triton X-100 ruptured the linkage between inhibitor and lipid. 6. A reconstituted sample of inhibitor–phosphatidylcholine complex was precipitated in a fully active form by dialysis against 2-mercaptoethanol, but treatment of the precipitate with NaCl yielded an extract which was inactive unless supplemented with fresh phosphatidylcholine. 7. We interpret the results as evidence that the inhibitor was present in vivo as a lipoprotein and that once the complex was dissociated by the action of detergent and the protein precipitated, there was an absolute need for exogenous phosphatidylcholine for its activity. The manner in which inhibitor associated with the outer membrane of rat liver mitochondria might regulate the activity of the enzyme in the supernatant has been suggested.

A series of bicyclam analogs connected through a heteroaromatic linker have been synthesized and evaluated for their inhibitory effects on HIV-1 (IIIB) and HIV-2 (ROD) replication in MT-4 cells. The activity of pyridine- and pyrazine-linked bicyclams was found to be highly dependent upon the substitution of the heteroaromatic linker connecting the cyclam rings. For example, 2,6- and 3,5-pyridine-linked bicyclams were potent inhibitors of HIV-1 and HIV-2 replication, whereas the 2,5- and 2,4-substituted pyridine-linked compounds exhibited substantially reduced activity and, in addition, were found to be highly toxic to MT-4 cells. We have subsequently discovered that these effects are not unique; amino-substituted linkers also have the potential to deactivate phenylenebis(methylene)-linked bicyclams. A model is proposed to explain the deactivating effects of the pyridine group in certain substitution patterns based on the ability of the pyridine nitrogen to participate in pendant conformations (complexation) with the adjacent azamacrocyclic ring, which may involve hydrogen bonding or coordination to a transition metal. The introduction of a sterically hindering group such as phenyl at the 6-position of the 2,4-substituted pyridine-linked bicyclam appears to prevent pendant conformations, providing an analog with comparable anti-HIV-1 and anti-HIV-2 activities to the parent m-phenylenebis(methylene)-linked bicyclam. The results of this study have been used to develop a quantitative structure−activity relationship model with improved predictive capability in order to aid the design of antiviral bis-azamacrocyclic analogs.

The design and synthesis of hydrazinopyridine bifunctional chelating agents (BCA's) featuring amide, ester, and disulfide groups are described. The BCA's site-specifically react with the free thiol groups of the tumor-specific monoclonal antibody fragment C46.3 using a one-pot in situ reduction and conjugation procedure from the F(ab‘)2 to give Fab‘−linker conjugates. Molar substitution ratios (MSR's) of the hydrazinopyridine conjugates were comparable to the theoretical (maximum) number of thiols per fragment determined by free hydrazine and residual thiol assays. The series of C46.3 Fab‘−linker conjugates were ^99mTc-labeled in greater than 95% radiochemical purity by incubation with ^99mTc−tricine for 1 h at room temperature. In order to evaluate the conjugates for radiopharmaceutical applications, the tumor localization and biodistribution properties of the radiolabeled Fab‘−linker conjugates, compared to the direct labeled fragment, were tested in nude mice bearing LS174T xenografts. Depending upon the structure of the linker connecting the radiolabeled hydrazinopyridine group to the antibody fragment, we observed a variation in kidney uptake and whole-body clearance. Diester- and monoester-linked conjugates exhibited lower kidney uptake and faster whole-body clearance than the corresponding linker containing amide groups. This result may be interpreted as evidence for rapid metabolism of ester compared to amide groups in the kidney following uptake. At 24-h postinjection, the monoester-linked conjugate ^99mTc−C46.3 Fab‘−BA displayed the highest tumor:blood ratio (16.2) compared to the directly labeled conjugate (6.6) and is therefore a potential clinical candidate for imaging breast and ovarian cancer.

A facility for carrying out beam-foil spectroscopic studies in the UV and visible region using the 400 kV electrostatic ion accelerator at Tata Institute of Fundamental Research, Bombay is described.

Helix formation in a 17-residue alanine-lysine peptide and analogous peptides with specific lysine→X substitutions, where X is 2,3-diamino-

Beam-foil spectrum of fluorine was recorded in the wavelength region of 2000–4500 Å using F+ion beams of energies ranging from 216 to 296 KeV. Some of the spectral lines of fluorine observed during the present investigation are hitherto unknown. Mean lifetimes of a few of the excited levels of F II and F III are reported for the first time.

A helix-stabilizing interaction between tyrosine and leucine or valine has been found in alanine-based peptide helices when the spacing is i,i+4. Control peptides have identical compositions but an i,i,+3 spacing. This is, to our knowledge, the first report of a helix-stabilizing interaction between two non-polar side-chains in an isolated helix. The results explain why, in an earlier study, leucine was found to have a helix propensity similar to that of alanine in an alanine-based peptide, whereas later work from another laboratory and our own has shown that alanine is markedly more helix-stabilizing than leucine in alanine-based peptides. The change in helix content resulting from the i,i, + 4 Tyr Leu interaction is comparable to the changes seen for other specific interactions between pairs of side-chains, such as ion-pair or Phe · His⁺ interactions. Copyright 1994, 1999 Academic Press