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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.comnet.2007.06.023 Byline: S. Jayashree (a), C. Siva Ram Murthy (b) Keywords: Ad hoc wireless network; Lifetime; MAC protocol; Performance evaluation Abstract: Ad hoc wireless networks possess highly constrained energy resources. The available energy resources should thus be used efficiently, in order to satisfy the requirements. Hence, the protocols at all the layers of the protocol stack should be energy aware and energy efficient. However, all the existing protocols are not energy aware and perform poorly in the presence of a limited power source. Even the energy aware protocols proposed for ad hoc networks do not consider all the characteristics of the underlying batteries. Hence, they fail to efficiently utilize the available energy. There also exist a few protocols, which, though battery unaware, unknowingly prove to be energy efficient. Thus, a mechanism is required to measure the efficiency of the protocols of ad hoc networks, in terms of the network lifetime. To the best of our knowledge, there has been no reported work till date for analyzing the lifetime of the ad hoc networks for various protocols. The protocols at all the layers of the protocol stack together decide the discharge of the battery source of a node. However, assuming that only the MAC protocols decide the battery performance, we focus on measuring the energy efficiency of MAC protocols. This paper primarily provides a novel generalized analytical model for estimating lifetime of ad hoc networks, in the presence of the following two kinds of MAC protocols: (i) reservation-based TDMA protocols and (ii) a specific class of CSMA protocols that try to follow a pattern, such as a round-robin scheduling, for packet transmission. Our model uses discrete-time Markov chain with probabilistic recovery to model the batteries of the ad hoc nodes. We found that our analytical model accurately estimates the lifetime of the network for various MAC protocols. We prove through analytical and simulation studies that energy awareness is crucial in deciding the performance of the MAC protocols for both homogeneous and heterogeneous ad hoc wireless networks. Author Affiliation: (a) Department of EECS, Massachusetts Institute of Technology, United States (b) Department of Computer Science and Engineering, Indian Institute of Technology, Madras, India Article History: Received 9 August 2006; Revised 3 May 2007; Accepted 29 June 2007 Article Note: (miscellaneous) Responsible Editor: V.R. Syrotiuk

The present study aimed to analyze the influence of SES on play skills in toddlers during a mother–child dyadic interaction. The study followed a cross sectional study design and included forty toddlers between the ages of 2–3 yrs, with their mothers. Participants were divided based on their SES into two groups as Group 1[Middle Socio-Economic State (MSES)] and Group 2 [Lower Socio- Economic Status (LSES)] with an equal number of participants in each group (20). Dyadic interaction between the mother and the toddler was recorded for 25 minutes for both the groups. The first and the last 5 minutes were excluded from the analysis and the middle 15 minutes were coded using the Play observation Scheme. The present study findings indicate a strong social class effect on the play skills demonstrated by toddlers. The findings of the present study indicated that the occurrences of interactive play such as Associative and Cooperative play were higher in toddlers of the MSES group compared to the LSES group. Another interesting finding is the significant difference in the occurrence of Simple and Complex pretend play between the two groups, with the MSES group outperforming their peers in the LSES group. An insight into the play skills of toddlers from low-income household would be helpful in creating awareness about the importance of play for holistic child development. It could also aid in the development of play assessment and intervention for toddlers from these socio-economic strata. [ABSTRACT FROM AUTHOR]

Chemotherapy is one of the most popular therapeutic strategies to treat cancer. However, cancer chemotherapeutics have often been associated with impairment of the immune system, which might consequently lead to an augmented risk of autoimmune disorders, such as rheumatoid arthritis. Though the accurate mechanistic facets of rheumatoid arthritis induction have not been interpreted yet, a conglomeration of genetic and environmental factors might promote its etiology. What makes the scenario more challenging is that patients with rheumatoid arthritis are at a significantly elevated risk of developing various types of cancer. It is intriguing to note that diverse cancer chemotherapy drugs are also commonly used to treat symptoms of rheumatoid arthritis. However, a colossal multitude of such cancer therapeutics has demonstrated highly varied results in rheumatoid arthritis patients, including both beneficial and adverse effects. Herein, we attempt to present a holistic account of the variegated modalities of this complex tripartite cross-talk between cancer, rheumatoid arthritis and chemotherapy drugs in order to decode the sinuous correlation between these two appalling pathological conditions. [ABSTRACT FROM AUTHOR]

Several studies have reported improvements in cognitive communicative abilities with working memory training and alternative therapeutic methods conducted separately. The present study aimed to investigate the effects of combining yoga and working memory training among healthy middle aged adults. A total of 45 participants were randomly assigned into three groups. Group 1 received both yoga and working memory training, group 2 received only working memory training and group 3 served as the control group. Working memory training was provided on six tasks. Yoga training involved pranayamas and mudras. Effects of training were assessed along with the self-perceptual rating of the participants towards training. Results reveal greater training effects among group 1 participants, followed by group 2 and group 3. Group 1 also reported better perception of training (p < 0.05) than group 2. The study highlights that yoga is not only an alternative approach, but also augmentative in improving cognitive communicative abilities. [ABSTRACT FROM AUTHOR]

Straw phonation exercises have been proved to be effective in improving voice quality among persons with voice pathology. The aim of the study was to investigate the effects of straw phonation as a warm-up exercise on maximum phonation duration, acoustic, and perceptual parameters of voice among Speech Language Pathologists. The study adopted a pretest-posttest design. Twenty-five females with the mean age range of 20.87 ± 1.15 years participated in the study and completed a series of straw phonation exercises for three cycles. Maximum phonation duration, acoustic, and self-perceptual measures were assessed before and after the straw phonation exercises. F0, jitter, shimmer, nose to harmonic ratio, intensity, F1, F2, F3, F4, Maximum phonation duration, and the post self-perceptual measures were analyzed. The results indicated a significant improvement in the F0, intensity, F1, F2, F4, Maximum phonation duration, and self-perceptual measures. Straw phonation exercises provides an easy and effective warm up technique to improve the voice quality among Speech Language Pathologists and can be considered before conducting therapy sessions. [ABSTRACT FROM AUTHOR]

Emerging concern regarding the remediation of environmental pollution has expanded tremendously in recent years. Pharmaceutical industries and agricultural sectors release an enormous amount of residues containing toxic pollutants at trace levels which poses a serious impact on the environment and human health. To cope with the effect of hazardous and toxic contaminants, numerous methodologies have been developed for the treatment of effluents released from the agrochemical and pharmaceutical industries. Amongst them, photocatalysis has gained much more attention for the degradation of pollutants due to its low cost, higher capability, green and eco-friendly approaches. Photocatalysts are the substrate that plays a key role in pollutant removal through photocatalysis by accelerating the necessary chemical reactions using a light source. In this review, the recent progress on photocatalysis and its fundamental mechanism in agrochemicals and pharmaceutical pollutant degradation was summarized. This review concisely discusses the incorporation of various metal oxides and nanomaterials into semiconductors for the effective degradation of contaminants. The current status and future research on different sectors and the difficulties in the photocatalytic removal of agrochemical and pharmaceutical pollutants are also reviewed in detail. [ABSTRACT FROM AUTHOR]

Summary: Objectives of the Study: In spite of voice being an important parameter of mate choice, none of the studies have described the acoustic characteristics of the sexually appealing voice. Method: Two hundred adults (100 men and 100 women) in the age range of 18–24 years were asked to narrate a topic, which was recorded directly onto Computerized Speech Lab (CSL) 6103 hardware. Recorded stimuli were presented to the six judges, and they were asked to indicate if the voice is sexually appealing on a five-point rating scale. The voices, which are consistently identified as sexually very attractive and unattractive were subjected to cepstral analysis through CSL. Results: The results of perceptual analysis revealed that 28 of the female voice samples and 39 of the male voice samples were rated as sexually attractive. These ratings were consistent within and across the judges. The cepstral analysis was then performed in all the voice samples and the results of independent t test revealed higher values of cepstral peak parameter (CPP) in the sexually attractive voices in comparison to the other voice samples in both the genders. The obtained results are discussed with respect to the harmonic organization in the voice samples. Conclusions: The results of cepstral analysis in sexually attractive voices revealed higher values of CPP in comparison to the voices rated as sexually not appealing. This could be because of the presence of well-defined harmonic structure evidenced in the sexually appealing voice in comparison to voices rated as very unappealing. Our findings suggest that cepstral analysis is a good indicator of sexually appealing voice. [Copyright &y& Elsevier]

Summary: Objectives: Unilateral vocal fold paralysis (UVFP) occurs because of the dysfunction of the vagus nerve innervating the larynx. It causes a characteristic breathy voice often accompanied by swallowing disability, a weak cough, and the sensation of shortness of breath. Clinical evaluation of voice is generally based on perceptive criteria and the acoustic analysis of voice. In the present study, it is hypothesized that there would be an abnormal reduction of the cepstral peak in speakers with UVFP relative to the normal controls, as they are characterized by a breathy voice because of inadequate closure of vocal folds. Methods: Phonation of sustained vowel /a/ sample was subjected to acoustic analysis using Computerized Speech Lab (CSL model 4150; Kay Pentax, Lincoln Park, NJ) software. The vowels were analyzed acoustically by the measurement of cepstral peak prominence (CPP). Results: The results of 2×2 analysis of variance revealed the main effects of the groups (clinical vs control group), indicating reduced cepstral peak value in the clinical group in comparison with controls. The main effect of gender was also significant, indicating a decrease in the CPP value in the female group in comparison with the male group. The results obtained were discussed with respect to the underlying pathophysiology. Conclusion: The present study investigated the CPP in subjects with UVFP. Cepstral deviations in the clinical group are explained to be the result of the presence of phonatory gap, leading to the lower values of CPP. [Copyright &y& Elsevier]

Summary: Chronic renal failure affects various body systems, one of which is the respiratory system. Because respiration is the prime source for speech, vocal dysfunctions are expected to be present in patients with chronic renal failure. The present study attempts to shed light on the changes in acoustic and aerodynamic characteristics of voice, if any, in patients with chronic renal failure. Phonation of sustained vowel /a/ was subjected to acoustic analysis using VAGHMI software (Voice and Speech Systems, Bangalore, Karnataka, India). Sustained phonation of /a/, /s/, and /z/ was recorded for the purpose of aerodynamic analysis. Independent t test was used to find the significant difference between the two groups. Chronic renal failure subjects showed significant deviation in frequency, perturbation, and aerodynamic measures when compared with normal subjects. These results are discussed with respect to the underlying pathophysiology. [Copyright &y& Elsevier]

Abstract: Background: Roux-en-Y gastric bypass (RYGB) benefits patients with type 2 diabetes mellitus (T2DM) and a body mass index (BMI) >35 kg/m2; however, its effectiveness in patients with T2DM and a BMI <35 kg/m2 is unclear. Asian Indians have a high risk of T2DM and cardiovascular disease at relatively low BMI levels. We examined the safety and efficacy of RYGB in Asian Indian patients with T2DM and a BMI of 22–35 kg/m2 in a tertiary care medical center. Methods: A total of 15 consecutive patients with T2DM and a BMI of 22–35 kg/m2 underwent RYGB. The data were prospectively collected before surgery and at 1, 3, 6, and 9 months postoperatively. Results: Of the 15 patients, 8 were men and 7 were women (age 45.6 ± 12 years). Their preoperative characteristics were BMI 28.9 ± 4.0 kg/m2, body weight 78.7 ± 12.5 kg, waist circumference 100.2 ± 6.8 cm, and duration of T2DM 8.7 ± 5.3 years. At baseline, 80% of subjects required insulin, and 20% controlled their T2DM with oral hypoglycemic medication. The BMI decreased postoperatively by 20%, from 28.9 ± 4.0 kg/m2 to 23.0 ± 3.6 kg/m2 (P <.001). All antidiabetic medications were discontinued by 1 month after surgery in 80% of the subjects. At 3 months and thereafter, 100% were euglycemic and no longer required diabetes medication. The fasting blood glucose level decreased from 233 ± 87 mg/dL to 89 ± 12 mg/dL (P <.001), and the hemoglobin A1c decreased from 10.1% ± 2.0% to 6.1% ± 0.6% (P <.001). Their waist circumference, presence of dyslipidemia, and hypertension improved significantly. The predicted 10-year cardiovascular disease risk (calculated using the United Kingdom Prospective Diabetes Study equations) decreased substantially for fatal and nonfatal coronary heart disease and stroke. No mortality, major surgical morbidity, or excessive weight loss occurred. Conclusion: RYGB safely and effectively eliminated T2DM in Asian Indians with a BMI <35 kg/m2. Larger, longer term studies are needed to confirm this benefit. [Copyright &y& Elsevier]

Abstract: Background: Laparoscopic sleeve gastrectomy (LSG) is becoming popular as a stand-alone procedure for the treatment of morbid obesity and related diseases. This retrospective study presents the outcomes of LSG with regard to weight loss and improvement in co-morbidities and quality of life (QOL) at the end of 3 years after surgery in a tertiary care hospital in Pune, India. Methods: A total of 23 patients with type 2 diabetes mellitus (6 men and 17 women) with morbid obesity (mean body mass index 40.7 ± 6.6 kg/m2) who had undergone LSG from 2004 to 2005 were selected for the present analysis. The percentage of excess weight loss and changes in co-morbidity status and QOL at the end of 3 years were calculated. The patients were simultaneously evaluated using the Bariatric Analysis and Reporting Outcome System scores. P values <.05 were considered significant. Results: At 36 months after surgery, the percentage of excess weight loss was 74.58%, a significant number of patients (16 of 23, P <.05) had had improvement in all co-morbidities, and 7 showed improvement in ≥1 co-morbidity. All patients indicated improvement in their QOL but not equally for all parameters included in the questionnaire. The Bariatric Analysis and Reporting Outcome System score was good in 4, very good in 4, and excellent in 15 of the 23 patients. Conclusion: Our data have shown that LSG is a highly effective and safe procedure for achieving weight loss, improving co-morbidities, and improving the QOL in patients with type 2 diabetes mellitus and morbid obesity during a long-term period. [Copyright &y& Elsevier]

Abstract: Background: To prospectively evaluate the efficacy and safety of laparoscopic sleeve gastrectomy (LSG) in Indian subjects with type 2 diabetes mellitus and a body mass index >33 kg/m2 in a tertiary care hospital in Pune, India. Morbid obesity associated with type 2 diabetes mellitus has many health implications. A definitive long-term strategy is needed to control obesity and its deleterious effects. LSG is one such approach. Methods: The patients who underwent LSG were followed up until the end of 1 year after surgery. The change in hemoglobin A1c levels, waist circumference, total body weight, and the use of oral hypoglycemic agents and insulin were studied. Results: A total of 53 patients (24 men and 29 women, age 46.5 ± 8.7 years, body mass index 45.2 ± 9.3 kg/m2, waist circumference 117 ± 18 cm, and hemoglobin A1c 8.4% ± 1.6%) fulfilled the entry criteria and underwent LSG. Before LSG, 48 patients (79%) required antidiabetic medication (oral hypoglycemic agents and insulin) and 5 managed their diabetes with diet control. At 1 month after LSG, 39 (81.2%) of 48 patients no longer required antidiabetic medications and had achieved euglycemia with diet control alone. The use of antidiabetic medications was reduced in 9 (18.8%) of 52 patients. At 1 year, euglycemia was observed in 51 patients (96.2%) without medication and 2 (3.8%) of the 53 patients had reduced their medication dosage. Conclusion: LSG is an effective adjunct in the treatment of type 2 diabetes mellitus in obese individuals. It appears that improvement in glycemic control is achieved even before weight reduction, and the possible mechanisms explaining this need further investigation. [Copyright &y& Elsevier]

Summary Background The cepstral measures are gaining attention in the voice analysis as it is reported to be strong predictor of voice impairments. As singer's voice is reported to be present with more harmonics, it can be hypothesized that there would be an increase in the value of cepstral parameters. Also, little is known about the cepstral characteristics of voices in Indian classical Carnatic singers; and hence, the present study was undertaken with an aim to characterize the singer's voice using cepstral measures. Methods Thirty Indian female classical Carnatic singers and 30 nonsingers participated in the study. Phonation of vowel /a/ was recorded at their habitual pitch and loudness. The cepstral peak prominence and smoothened cepstral peak prominence were analyzed using the Hillenbrand algorithm available in Speech Tool software. Mean and standard deviation was calculated for each group. Obtained scores were analyzed using independent t test. Results Mean raw scores were found to be increased in classical Carnatic singers in comparison with nonsingers. Results of independent t test revealed significant difference between the means of singers and nonsingers for both the cepstral measures at P < 0.05. Conclusions The present study investigated the cepstral characteristic of voice in singers and nonsingers. Results revealed that there was a significant difference between the means of singers and nonsingers indicating that cepstral parameters were higher among the singers in comparison with nonsingers. The obtained results were attributed to the harmonic organization in the voices of singers. [ABSTRACT FROM AUTHOR]

Summary: Background: Spectrum is a fast Fourier transform-generated power spectrum extracted from the speech sample. It is reported to provide a quantitative acoustic index of the degree of glottal abduction and adduction in voices perceived to be breathy or pressed. In the present study, it was hypothesized that there would be abnormal reduction of higher harmonic amplitudes relative to the amplitude of the first harmonics in the subjects with vocal nodules and hence the present study was carried out. Method: One hundred twenty participants were divided into clinical group and control group. They were instructed to phonate /a/ at their most comfortable pitch and loudness. Fourier transformation of the recorded acoustic signal was first performed to create a spectrum. Amplitudes were measured for the first and second harmonics (H1 and H2) as well as the harmonics at the first, second, and third formants (A1, A2, and A3) using the Computerized Speech Science Lab (Kay Pentax, Lincoln, NJ). Results: There was a significant difference between the means of two groups for all the parameters, such as H1-H2, H1-A1, H1-A2, and H1-A3 at P <0.05. The obtained results are discussed with respect to the underlying pathophysiology. Conclusions: The present study investigated the vowel harmonic amplitude differences in persons with vocal nodules. The results revealed a significant difference between the two groups for the vowel harmonic amplitude differences. This particular measure could be used to track the changes following the vocal treatment. [Copyright &y& Elsevier]

Summary: Objectives: Traditional measures of dysphonia were reported to be unreliable, and the measurements of cepstral peak prominence (CPP) have been shown to correlate well with perceptions of breathiness. Hence, the present study was hypothesized that there would be abnormal reduction of the cepstral peak in the speakers with vocal nodules relative to the normal controls as they are characterized by hoarse and breathy voice due to inadequate closure of vocal folds. Method: Phonation of sustained vowel /a/ was subjected to acoustic analysis using Computerized Speech Lab (CSL model 4150) software. The vowels were analyzed acoustically with the measurement of CPP. Results: Independent t test was employed to compare the significant differences between the clinical and the control groups in both males and females. The results revealed significant differences across the two groups at P <0.05. The obtained results were discussed with respect to the underlying pathophysiology. Conclusion: The present study investigated the CPP in subjects with vocal nodules. Cepstral deviations in the clinical group are explained due to the presence of laryngeal pathology leading to the lower values of CPP. [Copyright &y& Elsevier]