Analytical prediction of labyrinth-seal-flow-induced arotor excitation forces

An analytical method to calculate the rotor excitation forces arising from labyrinth seals is presented. The objective is to model the gas flow through the seal clearance passages and cavities when the rotor is positioned eccentricly relative to the stator center. The seal flow model used in the analysis yields solutions which validate the experimentally observed influence of seal parameters on seal forces reported in the literature. The analytically predicted seal pressure distributions and forces were compared with published experimental results

EFFECT OF LENGTH OF STAY ON GUEST SATISFACTION-AN EMPIRICAL STUDY OF INDIAN HOTEL INDUSTRY

The unpredictable and dynamic changes experienced by the corporate world have transformed the business environment. Now the key for remaining successful is in retaining customers rather than in acquiring customers. Customer satisfaction is considered the essence of success in today's highly competitive world of business, and it has become the corporate goal as more and more companies strive for quality in their product. The purpose of this article is to examine the influence of ‘length of stay’of a guest in a hotel, on satisfaction, revisit intention and making favorable referrals. This paper considers the reaction of ‘international travelers’ who have boarded their flight from Chennai, India. Outcome of this research indicates that one of the critical challenges faced by the hoteliers is to create opportunities to their guests to experience (all) the facilities available in the hotel, especially for those who stay for a shorter period. Results shows that length of stay positively influences the satisfaction level but not revisit attitude and positive referrals. However satisfied guests tends to revisit the same hotel in future and likely to refer to their friends and relatives.’ Satisfaction is the nucleus and everything revolves around it and duration of stay is one of the major determinants of hotel factors which is a major predictor of satisfactionHotel industry, Guest satisfaction, Length of stay, purpose of visit, revisit, recommendation

The relaxation of OH (v = 1) and OD (v = 1) by H2O and D2O at temperatures from 251 to 390 K

We report rate coefficients for the relaxation of OH(v = 1) and OD(v = 1) by H2O and D2O as a function of temperature between 251 and 390 K. All four rate coefficients exhibit a negative dependence on temperature. In Arrhenius form, the rate coefficients for relaxation (in units of 10–12 cm3 molecule–1 s–1) can be expressed as: for OH(v = 1) + H2O between 263 and 390 K: k = (2.4 ± 0.9) exp((460 ± 115)/T); for OH(v = 1) + D2O between 256 and 371 K: k = (0.49 ± 0.16) exp((610 ± 90)/T); for OD(v = 1) + H2O between 251 and 371 K: k = (0.92 ± 0.16) exp((485 ± 48)/T); for OD(v = 1) + D2O between 253 and 366 K: k = (2.57 ± 0.09) exp((342 ± 10)/T). Rate coefficients at (297 ± 1 K) are also reported for the relaxation of OH(v = 2) by D2O and the relaxation of OD(v = 2) by H2O and D2O. The results are discussed in terms of a mechanism involving the formation of hydrogen-bonded complexes in which intramolecular vibrational energy redistribution can occur at rates competitive with re-dissociation to the initial collision partners in their original vibrational states. New ab initio calculations on the H2O–HO system have been performed which, inter alia, yield vibrational frequencies for all four complexes: H2O–HO, D2O–HO, H2O–DO and D2O–DO. These data are then employed, adapting a formalism due to Troe (J. Troe, J. Chem. Phys., 1977, 66, 4758), in order to estimate the rates of intramolecular energy transfer from the OH (OD) vibration to other modes in the complexes in order to explain the measured relaxation rates—assuming that relaxation proceeds via the hydrogen-bonded complexes

Reduction of seafood processing wastewater using technologies enhanced by swim–bed technology

The increasing growth of the seafood processing industries considerably requires more industrial process activities and water consumption. It is estimated that approximately 10–40 m3 of wastewater is generated from those industries for processing one-tonne of raw materials. Due to limitations and regulations in natural resources utilization, a suitable and systematic wastewater treatment plant is very important to meet rigorous discharge standards. As a result of food waste biodegradability, the biological treatment and some extent of swim-bed technology, including a novel acryl-fibre (biofilm) material might be used effectively to meet the effluent discharge criteria. This chapter aims to develop understanding on current problems and production of the seafood wastewater regarding treatment efficiency and methods of treatment

A Study on Left Ventricular Diastolic Function assesed by Echo in Metabolic Syndrome

INTRODUCTION: Metabolic syndrome Characterised by four clinical elements: these are Atherogenic dyslipidemia, insulin resistance (IR), central Obesity, and high blood pressure. The metabolic syndrome includes group of cardiac risk factors that act simultaneously. The persons with this syndrome who are worst prognosis cardiovascular events This is a is a group of components distressing about 20- 25% of adults population in developed countries. In India, prevalence is about 21% to 25% in adults. elevated BP, Hyperglycemia and central obesity harmfully affected in heart both physiologically and pathologically. This disease and its components, such as hyper glycemia, raised BP, Lipid profile abnomalities and central obesity are progressively more common among our people due to inactive life style. These people most commonly manifested as Heart failure but patients had normal ejection fraction (HFNEF). Persons with the metabolic syndrome have a high incidence of heart failure HF. patients with metabolic syndrome they are greater threat of cardiac events than not associated this disease. This study aimed to evaluate the association between Left ventricular diastolic dysfunction and Metabolic syndrome. So far there is minimal literature in our institute regarding the study of diastolic dysfunction in subjects with metabolic syndrome. AIMS AND OBJECTIVES: 1. To assess left ventricular function in metabolic syndrome. 2. To grade the diastolic dysfunction and clinical outcome. MATERIALS AND METHODS: Study Site: Department of General Medicine, Government Stanley Medical College and Hospital, Chennai. Collaborating Departments: Department of Cardiology and Department of Medical Biochemistry. Study Design: Longitudinal study. Study Period: June 2012 to November 2012. Sample Size: Using the above mentioned criteria 50 subjects were recruited. Sampling Method: Convenience sampling method was adopted. Selection of Study Population: Inclusion Criteria: Patients meeting criteria for metabolic syndrome without co morbid illness Exclusion Criteria: • Cushing syndrome. • Hypothyroidism. • Anasarca. • Known heart disease patients. • Gout. • Polycystic ovarian disease. STATISTICAL ANALYSIS: Statistical analysis was done using • Percentages, • Mean values, • Standard deviation, • Standard error, • Chi square test, • T-test unpaired, Level of significance used is 0.05 for the corresponding degree of freedom to draw the inference. A p value <0.05 was considered statistically significant. CONCLUSION: • Left ventricular diastolic dysfunction was observed in 52% of total subjects and 48% of total subjects have normal left ventricular function. 36% impaired relaxation cases and 16% pseudo normal cases contributed to th 52% prevalence of LVDD. • Recognition of pseudonormal pattern of utmost importance. It is an intermediary stage between mild impaired relaxation state and advanced restrictive filling stage. • LVDD had no correlation with blood pressure, fasting blood sugar, waist measurement, triglycerides and high density lipoproteins level. • LVDD is the earliest manifestation of metabolic disease related cardiomyopathy. Hence detecting it early will prevent disease progression to symptomatic cardiac failure and bring down the disease burden. • The clinical significance of the findings in terms of prognosis and treatment needs to be determined. • This study is a hypothesis generating study. • Hence results from our study needs to be reinvestigated using robust research designs like cohort studies. • Conventional echocardiography is a simple economical test for detecting LVDD in metabolic syndrome patients who are asymptomatic. • ECHO diagnostic factors like E/A ratio, DT and IVRT should be should be studied further and developed into accurate cost effective screening tools for screening asymptomatic LVDD

Synthesis of macrocyclic receptors with intrinsic fluorescence featuring quinizarin moieties

An unprecedented class of macrocycles with intrinsic fluorescence consisting of phenolic trimers and quinizarin is developed. Though they are lacking strong hydrogen bonds as observed in calixarenes, the two examples introduced here each adopt a vase-like conformation with all four aromatic units pointing in one direction (syn orientation). This “cone” conformation has been confirmed by NMR spectroscopy, molecular modeling, and X-ray crystallography. The laminar, electron-rich fluorophore as part of the macrocycle allows additional contacts to enclosed guest molecules

Therapeutic DNA vaccine induces broad T cell responses in the gut and sustained protection from viral rebound and AIDS in SIV-infected rhesus macaques.

Immunotherapies that induce durable immune control of chronic HIV infection may eliminate the need for life-long dependence on drugs. We investigated a DNA vaccine formulated with a novel genetic adjuvant that stimulates immune responses in the blood and gut for the ability to improve therapy in rhesus macaques chronically infected with SIV. Using the SIV-macaque model for AIDS, we show that epidermal co-delivery of plasmids expressing SIV Gag, RT, Nef and Env, and the mucosal adjuvant, heat-labile E. coli enterotoxin (LT), during antiretroviral therapy (ART) induced a substantial 2-4-log fold reduction in mean virus burden in both the gut and blood when compared to unvaccinated controls and provided durable protection from viral rebound and disease progression after the drug was discontinued. This effect was associated with significant increases in IFN-γ T cell responses in both the blood and gut and SIV-specific CD8+ T cells with dual TNF-α and cytolytic effector functions in the blood. Importantly, a broader specificity in the T cell response seen in the gut, but not the blood, significantly correlated with a reduction in virus production in mucosal tissues and a lower virus burden in plasma. We conclude that immunizing with vaccines that induce immune responses in mucosal gut tissue could reduce residual viral reservoirs during drug therapy and improve long-term treatment of HIV infection in humans

Design and Development of an Efficient Branch Predictor for an In-order RISC-V Processor

Conditional branches are a serious issue in the pipelined processor. The branch direction and branch target address are determined and calculated by the processor after several cycles of the instruction decode, which results in the pipeline stall. Pipeline stall leads to control hazards in the processor and results in performance degradation. To increase the rate of the instruction flow in modern processors, branch prediction is used. Branch prediction provides an ideal speedup in performance of the processor. The processor predicts the direction in the branch prediction and determines instructions in accordance with the predicted path. The processor tests any prediction for the branch when the branch condition is calculated. If the prediction is incorrect, the processor will automatically abort all instructions taken along the wrong path and return the state to the address of the determined branch. An inaccurate branch predictor results in increased program run-time and leads to higher power consumption. Once the position of a branch is known, the actual target address of the next instruction must also be determined along the expected path. If the branch is expected not to be taken, the destination address is simply the address of the current branch plus the size of the command word. Unless the branch is to be taken, then the target depends on the branch type. The branch target buffer (BTB) can reduce branch efficiency by predicting the branch path and storing information used by branch. There are no stalls if the branch entry is found in BTB, and the calculation is accurate, or the penalty shall be two cycles or more. This paper focuses on the design and development of branch predictor with BTB for the fetch unit, which further integrates to an in-order pipelined RISC-V processor. The performance of the RISC-V core in terms of clock cycle latency, instruction per cycle (IPC), was measured and analyzed

Localized microstimulation of primate pregenual cingulate cortex induces negative decision-making

The pregenual anterior cingulate cortex (pACC) has been implicated in human anxiety disorders and depression, but the circuit-level mechanisms underlying these disorders are unclear. In healthy individuals, the pACC is involved in cost-benefit evaluation. We developed a macaque version of an approach-avoidance decision task used to evaluate anxiety and depression in humans and, with multi-electrode recording and cortical microstimulation, we probed pACC function as monkeys performed this task. We found that the macaque pACC has an opponent process-like organization of neurons representing motivationally positive and negative subjective value. Spatial distribution of these two neuronal populations overlapped in the pACC, except in one subzone, where neurons with negative coding were more numerous. Notably, microstimulation in this subzone, but not elsewhere in the pACC, increased negative decision-making, and this negative biasing was blocked by anti-anxiety drug treatment. This cortical zone could be critical for regulating negative emotional valence and anxiety in decision-making.National Institutes of Health (U.S.) (Javits Merit Grant R01 NS025529)United States. Office of Naval Research (N000140710903)National Parkinson Foundation (U.S.) (Lynn Diamond Fellowship

Investigation into the security and privacy of iOS VPN applications

Due to the increasing number of recommendations for people to use Virtual Private Networks (VPNs) to protect their privacy, more application developers are creating VPN applications and publishing them on the Apple App Store and Google Play Store. In this ‘gold rush’, applications are being developed quickly and, in turn, not being developed with security in mind.This paper investigated a selection of VPN applications available on the Apple App Store (for iOS devices) and tested the applications for security and privacy issues. This includes testing for any traffic being transmitted over plain HTTP, DNS leakage and transmission of personally identifiable information (such as phone number, International Mobile Equipment Identity (IMEI), email address, MAC address) and evaluating the security of the tunneling protocol used by the VPN.The testing methodology involved installing VPN applications on a test device, simulating network traffic for a pre-defined period of time and capturing the traffic. This allows for all traffic to be analysed to check for anything being sent without encryption. Other issues that often cause de-anonymization with VPN applications such as DNS leakage were also considered.The research found several common security issues with VPN applications tested, with a large majority of applications still using HTTP and not HTTPS for transmitting certain data. A large majority of the VPN applications failed to route additional user data (such as DNS queries) through the VPN tunnel. Furthermore, just fifteen of the tested applications were found to have correctly implemented the best-recommended tunneling protocol for user security.Outside of the regular testing criteria, other security anomalies were observed with specific applications, which included outdated servers with known vulnerabilities, applications giving themselves the ability to perform HTTPS interception and questionable privacy policies. From the documented vulnerabilities, this research proposes a set of recommendations for developers to consider when developing VPN applications