The Use of Almost Linear Phase IIR filters In DFT Modulated Filter Banks for Communication Systems

This paper is on the use and performance of M-path polyphase Infinite Impulse Response (IIR) filters for channelisation, conventionally where Finite Impulse Response (FIR) filters are preferred. This paper specifically focuses on the Discrete Fourier Transform (DFT) modulated filter banks, which are known to be an efficient choice for channelisation in communication systems. In this paper, the low-pass prototype filter for the DFT filter bank has been implemented using an M-path polyphase IIR filter and we show that the spikes present at the stopband can be avoided by making use of the guardbands between narrowband channels. It will be shown that the channelisation performance will not be affected when polyphase IIR filters are employed instead of their counterparts derived from FIR prototype filters. Detailed complexity and performance analysis of the proposed use will be given in this article

ROLE OF ANTIOXIDANTS AND NUTRITION IN OXIDATIVE STRESS: A REVIEW

Human body is known to experience positive stress that keeps it vigilant and protects it from biological and physical threats. This stress turns negative when a person is confronted with continuous challenges. Also, stress and nutrition have always run in synergism with each other. Nutritional value of a person's diet depends on the overall mixture or balance of food that is eaten over a period of time, as well as on the needs of the individual. The body relies on obtaining its anti-oxidants from food and other supplements. These nutritional requirements of antioxidants are enormously altered in diseased conditions. In view of the immense medicinal importance of antioxidants, an effort has been made in this article to bring together information about the role of nutrition and antioxidants such as carotenoids, vitamins, some important minerals in combating free radical generation and in general, boosting normal immune mechanisms. The present review is an attempt to generate interest in the scientific fraternity of their immense potential in preventing and treating several common diseases. Keywords: Antioxidants, Free radicals, Balanced diet, Nutrition, Oxidative stress, Vitamins

'I Sat Filling in This Form While Smoking and It Was Divine'. An Analysis of Free-Text Comments from Smokers Who Report They Have No Intention of Quitting in the Next Six Months

INTRODUCTION: Smokers unmotivated to quit are neglected by smoking cessation research. Free-text comment analysis is a potentially useful way to gain insight into this group's beliefs. AIMS: To analyse the free-text comments provided by smokers unmotivated to quit as part of a randomized controlled trial of computer-tailored feedback for smoking cessation. METHOD: A random sample of 58,660 smokers were sent a smoking behaviour questionnaire (SBQ). The responses and follow-up outcomes of those providing free-text comments were compared to those who did not to assess the representativeness of the former group of smokers. The comments of participants unmotivated to quit (631) were thematically analysed. RESULTS: Those who provided a comment differed from those who did not on variables including education level and quit attempts at six-month follow-up. Emergent themes included; justification of smoking and restricting smoking instead of quitting. CONCLUSIONS: The findings illustrate the value of free-text comments in identifying issues important to respondents. The identified themes highlight areas for future research in smokers unmotivated to quit including cutting down as a path to quitting and explicit messages regarding the inability of positive health behaviours to balance out the negative impact of smoking on health. Trial registration: Current Controlled Trials ISRCTN05385712

Assessing the fidelity of delivery of an intervention to increase attendance at the English Stop Smoking Services

Background: Implementation fidelity refers to the extent to which a proposed intervention is enacted as designed and is necessary to determine how much the intervention in question is the primary mechanism in any changes observed. Start2quit was a randomised controlled trial that aimed to improve attendance at the English Stop Smoking Service (SSS). The complex intervention combining computer-tailored personal risk letters and no-commitment (“taster”) sessions aimed at encouraging attendance at the SSS doubled attendance at the SSS and significantly increased abstinence rates, although attendance and abstinence varied between participating SSSs. Assessment of the fidelity of the delivery of the taster sessions to the protocol was embedded into the trial and is the focus of this study. / Methods: Eighteen SSSs participated in the study. Taster sessions were delivered by SSS advisors in the area. Of the 131 sessions delivered, 93 (71 %) were recorded and 41 (31.3 %) were selected for transcription and analysis. The taster session protocol contained 73 specified behaviours, which were independently classified into component behaviour change techniques (BCTs) using an established taxonomy for smoking cessation. All transcripts were coded by two authors with 25 % additionally coded by a third. The fidelity of each taster session was expressed as the percentage of overall protocol-specified behaviours that were delivered. Adherence to each BCT was measured as the number of behaviours applied by the advisors within each BCT divided by the total number classified within each. / Results: Adherence of protocol-specified behaviours was relatively high (median 71.23 %), though there was considerable variation (28.76 to 95.89 %) in individual sessions. Median fidelity to specific BCTs across sessions also varied from 50 to 100 %. Shorter sessions, sessions run jointly by two advisors, by female advisors, or by advisors aged 45 to 54 were associated with higher levels of adherence. There was no association between adherence and subsequent attendance at the SSS. / Conclusions: These results suggest that the delivery of the intervention of this study is not likely to have been impacted by issues of fidelity. As such, we can have greater confidence that variability in the main outcome is not due to variability in SSS advisor adherence to the protocol of the taster sessions. / Trial registration: Current Controlled Trials ISRCTN7656191

Medial circumflex femoral artery with different origin and course: a case report and review of the literature

The femoral artery (FA) and its branches play important roles in the arterial supply of the lower extremity. If the femoral artery is occluded, the circulation of the extremity is maintained by certain anastomoses. Therefore, identification of variations of these arteries is critical from a clinical and surgical point of view. During routine anatomical dissections for student education at the Department of Anatomy of the School of Medicine at Ondokuz Mayls University, a variation of the medial circumflex femoral artery (MCFA) was observed and photographed in a male, formalin-fixed cadaver aged 55 years. In this case, MCFA branched off from the posterolateral aspect of the FA, 32 mm distal to the inguinal ligament. A frequency rate of 17–26% has been reported regarding this variation. However, MCFA emerging from the postero-lateral aspect of the FA and its course, as in this case, is not that frequent. Knowledge of anomalies in the emergence and course of the arteries that join the cruciate anastomosis and are important in the arterial supply of the head and neck of the femur appear to be a critical component that requires caution during surgical interventions towards this region

Absence of the musculocutaneous nerve together with unusual innervation of the median nerve

During routine anatomical dissections, absence of the musculocutaneous nerve was determined in a 58-year-old male cadaver. Moreover, the biceps brachii and brachialis muscles were innervated by two separate branches which divided from the median nerve instead of the musculocutaneous nerve. From a branch that divides from the main trunk of the median nerve at nearly the middle of the arm a motor branch again divided that innervated the brachialis muscle and a sensory branch that conveyed the sense of the lateral part of the forearm. Furthermore, it was found that the brachial artery divided into its terminal branches, the radial and ulnar arteries. We believe that this rare variation of the median nerve will shed light upon surgical procedures involving the median nerve

Collateral and Debt Maturity Choice. A Signaling Model

This paper derives optimal loan policies under asymmetric information where banks offer loan contracts of long and short duration, backed or unbacked with collateral. The main novelty of the paper is that it analyzes a setting in which high quality firms use collateral as a complementary device along with debt maturity to signal their superiority. The least-cost signaling equilibrium depends on the relative costs of the signaling devices, the difference in firm quality and the proportion of good firms in the market. Model simulations suggest a non-monotonic relationship between firm quality and debt maturity, in which high quality firms have both long-term secured debt and short-term secured or non-secured debt.

Difference Spectrophotometric Method for Estimation of Amitriptyline Hydrochloride in Bulk Drug

See PDF for full tex

Discovering Valuable Items from Massive Data

Suppose there is a large collection of items, each with an associated cost and an inherent utility that is revealed only once we commit to selecting it. Given a budget on the cumulative cost of the selected items, how can we pick a subset of maximal value? This task generalizes several important problems such as multi-arm bandits, active search and the knapsack problem. We present an algorithm, GP-Select, which utilizes prior knowledge about similarity be- tween items, expressed as a kernel function. GP-Select uses Gaussian process prediction to balance exploration (estimating the unknown value of items) and exploitation (selecting items of high value). We extend GP-Select to be able to discover sets that simultaneously have high utility and are diverse. Our preference for diversity can be specified as an arbitrary monotone submodular function that quantifies the diminishing returns obtained when selecting similar items. Furthermore, we exploit the structure of the model updates to achieve an order of magnitude (up to 40X) speedup in our experiments without resorting to approximations. We provide strong guarantees on the performance of GP-Select and apply it to three real-world case studies of industrial relevance: (1) Refreshing a repository of prices in a Global Distribution System for the travel industry, (2) Identifying diverse, binding-affine peptides in a vaccine de- sign task and (3) Maximizing clicks in a web-scale recommender system by recommending items to users

On the absence of radio halos in clusters with double relics

Pairs of radio relics are believed to form during cluster mergers, and are best observed when the merger occurs in the plane of the sky. Mergers can also produce radio halos, through complex processes likely linked to turbulent re-acceleration of cosmic-ray electrons. However, only some clusters with double relics also show a radio halo. Here, we present a novel method to derive upper limits on the radio halo emission, and analyse archival X-ray Chandra data, as well as galaxy velocity dispersions and lensing data, in order to understand the key parameter that switches on radio halo emission. We place upper limits on the halo power below the $P_{\rm 1.4 \, GHz}\, M_{500}$ correlation for some clusters, confirming that clusters with double relics have different radio properties. Computing X-ray morphological indicators, we find that clusters with double relics are associated with the most disturbed clusters. We also investigate the role of different mass-ratios and time-since-merger. Data do not indicate that the merger mass ratio has an impact on the presence or absence of radio halos (the null hypothesis that the clusters belong to the same group cannot be rejected). However, the data suggests that the absence of radio halos could be associated with early and late mergers, but the sample is too small to perform a statistical test. Our study is limited by the small number of clusters with double relics. Future surveys with LOFAR, ASKAP, MeerKat and SKA will provide larger samples to better address this issue.Comment: 12 pages, 7 figures, MNRAS accepte