85 research outputs found

    Efficient Broadcasting for a Mobile Ad-hoc Network based Peer-to-peer Community Radio Service

    Get PDF
    Ad-hoc networks consisting entirely of simple mobile phones can be used to deploy village level telephony. We investigate a novel application for such networks – a peer-to peer community radio service. We envision a system, where any user in the network is equally empowered to generate and distribute audio content to the entire network, using his or her mobile phone. This study concentrates on a critical aspect of this service – the choice of the network-wide broadcast protocol. Using extensive simulations, we evaluate the suitability of various broadcast techniques for a rural peer-to-peer mobile adhoc network. Our simulations identify the best choice of protocols under various village network conditions while simultaneously identifying limitations of the current protocols.

    An Adaptive Probabilistic Model for Broadcasting in Mobile Ad Hoc Networks

    Get PDF
    Ad hoc peer-to-peer mobile phone networks (phone MANETs) enable cheap village level telephony for cash-strapped, off-the-grid communities. Broadcasting is a fundamental operation in such manets and is used for route discovery. This paper proposed a new broadcast technique that is lightweight, efficient and incurs low latency. Using extensive simulations, we compare our proposed technique to existing lightweight protocols. The results show that our technique is successful in outperforming existing lightweight techniques on the criteria that are critical for a phone-MANET.

    A Voice for the Voiceless: Peer-to-peer Mobile Phone Networks for a Community Radio Service

    Get PDF
    We propose a new application for mobile ad-hoc networks (MANETs) – community radio. We argue how MANETS help overcome important limitations in how community radio is currently operationalized. We identify critical design elements for a MANET based community radio service and propose a broad architecture for the same. We then investigate a most critical issue– the choice of the network wide broadcast protocol for the audio content. We identify desired characteristics of a community radio broadcasting service. We choose and evaluate eight popular broadcasting protocols on these characteristics, to find the protocols most suited for our application.

    Effect of Caesalpinia pulcherrima (L.) Sw. seeds on serum glucose and other metabolic parameters of normal and alloxan - induced diabetic rats

    Get PDF
    Oral administration of the ethanol extract of Caesalpinia pulcherrima seeds (CP - 250 and 500 mg/kg) caused significant fall in blood glucose levels even at 2½ h after a single dose of treatment in normal fasted and glucose loaded Wistar rats. At 250 mg/kg dose level, CP completely prevented the elevation of blood glucose caused by oral glucose feeding. In alloxan diabetic rats, CP was able to lower the blood glucose level to around 132 mg / 100 ml from 10th day and thereafter. The biochemical findings were supported by histopathological studies of liver, kidney and pancreas of control and treated rats. CP was able to increase catalase levels of diabetic rats. Reduced levels of serum protein and elevated levels of serum glutamate oxaloacetate transaminase (SGOT), serum glutamate pyruvate transaminase(SGPT), alkaline phosphatase(ALP), cholesterol, triglycerides, creatinine and uric acid were almost normalised in CP treated diabetic rats. CP was also able to reduce in vitro lipid peroxidation in rat liver microsomes and inhibit 1- diphenyl – 2-picryl hydrazyl (DPPH) induced free radicals significantly

    Open(ing) Access: Top Health Publication Availability to Researchers in Low- and Middle-Income Countries

    Get PDF
    Introduction: Improving access to information for health professionals and researchers in low- and middle-income countries (LMICs) is under-prioritized. This study examines publication policies that affect authors and readers from LMICs. Methods: We used the SHERPA RoMEO database and publicly available publishing protocols to evaluate open access (OA) policies, article processing charges (APCs), subscription costs, and availability of health literature relevant to authors and readers in LMICs. Categorical variables were summarized using frequencies with percentages. Continuous variables were reported with median and interquartile range (IQR). Hypothesis testing procedures were performed using Wilcoxon rank sum tests, Wilcoxon rank sum exact tests, and Kruskal-Wallis test. Results: A total of 55 journals were included; 6 (11%) were Gold OA (access to readers and large charge for authors), 2 (3.6%) were subscription (charge for readers and small/no charge for authors), 4 (7.3%) were delayed OA (reader access with no charge after embargo), and 43 (78%) were hybrid (author’s choice). There was no significant difference between median APC for life sciences, medical, and surgical journals (4,850[4,850 [3,500–8,900]vs.8,900] vs. 4,592 [3,5003,500–5,000] vs. 3,550[3,550 [3,200–3,860];p=0.054).ThemedianUSindividualsubscriptioncosts(USD/Year)weresignificantlydifferentforlifesciences,medical,andsurgicaljournals(3,860]; p = 0.054). The median US individual subscription costs (USD/Year) were significantly different for life sciences, medical, and surgical journals (259 [209209–282] vs. 365[365 [212–744]vs.744] vs. 455 [365365–573]; p = 0.038), and similar for international readers. A total of seventeen journals (42%) had a subscription price that was higher for international readers than for US readers. Conclusions: Most journals offer hybrid access services. Authors may be forced to choose between high cost with greater reach through OA and low cost with less reach publishing under the subscription model under current policies. International readers face higher costs. Such hindrances may be mitigated by a greater awareness and liberal utilization of OA policies

    Rethinking Global Health Education in Plastic Surgery Residency

    Get PDF
    Surgical disease is now among the most common, preventable, and growing contributors to the global burden of disease. The attitudes of trainees toward global surgery and the viability of a global surgery as an academic track have blossomed. More optimized experiences within residency education are necessary, however, to prepare the next generation of global surgeons. The field of plastic surgery is thus at an important crossroads in the effort to incorporate global surgery into training programs in a uniform fashion across the country. The recent American Council of Academic Plastic Surgeons meeting in February 2020 was dedicated to identifying strategies that will enhance the adoption of global surgery practices within plastic surgery. In this article, we discuss the principles, themes, and ideas that emerged from this session, and further develop concrete initiatives believed to be potentially fruitful. Some have been discussed in other surgical disciplines or presented in isolation to the plastic surgery community, but never as a cohesive set of recommendations that take into account the background and shortfalls of the current model for global health education in the 21st century. We then introduce five recommendations to optimize learner education: (1) clarification of learner expectations and roles; (2) domestic teaching for optimization of field experiences; (3) expansion of longitudinal, formal rotations; (4) strengthening of the role of research; and (5) integration of program financing

    Hair follicle specific ACVR1/ALK2 critically affects skin morphogenesis and attenuates wound healing

    Full text link
    The bone morphogenic protein signaling (BMP) is intricately involved in the quiescence and regulation of stem cells through activation of BMP receptors. Hair follicle stem cells play a critical role in cutaneous homeostasis and regeneration. Here, we utilize a novel mouse model with targeted overexpression of the BMP receptor ALK2/ACVR1 in hair follicle stem cells, to characterize its role in skin development and postnatal wound healing. Initial histologic evaluation demonstrated significant dysregulation in hair follicle morphogenesis in mutant mice. These demonstrated increased numbers of individual hair follicles with altered morphology and localization. Mutant follicles were found to exhibit elevated proliferative activity as well as increased prevalence of CD34 and ITGA6 positive follicle stem cells. Interestingly, constitutive overexpression of ALK2 resulted in attenuation of cutaneous wound healing. These findings demonstrate that hair follicle specific ALK2 is intricately involved in maintenance of the stem cell niche and wound healing.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138367/1/wrr12549_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138367/2/wrr12549.pd

    Diminished Chondrogenesis and Enhanced Osteoclastogenesis in Leptin-Deficient Diabetic Mice (ob/ob) Impair Pathologic, Trauma-Induced Heterotopic Ossification

    Full text link
    Diabetic trauma patients exhibit delayed postsurgical wound, bony healing, and dysregulated bone development. However, the impact of diabetes on the pathologic development of ectopic bone or heterotopic ossification (HO) following trauma is unknown. In this study, we use leptin-deficient mice as a model for type 2 diabetes to understand how post-traumatic HO development may be affected by this disease process. Male leptin-deficient (ob/ob) or wild-type (C57BL/6 background) mice aged 6?8 weeks underwent 30% total body surface area burn injury with left hind limb Achilles tenotomy. Micro-CT (?CT) imaging showed significantly lower HO volumes in diabetic mice compared with wild-type controls (0.70 vs. 7.02?mm3, P?Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140207/1/scd.2015.0135.pd

    “Vaai Ganam” - a screening program for early detection of oral potentially malignant disorders and oral cancer among truck drivers in Chennai – a cross-sectional survey

    Get PDF
    Introduction: Truck drivers, though forming an integral part of a vital trade link for the Indian population, lack basic life insurance and health care benefits offered by other organized sectors in Indian Industries. This paper aims to present the initial findings of the “VaaiGanam” program which proposes to identify tobacco use and the prevalence of Oral potentially malignant disorders (OPMDs) among truck drivers who are stationed or passing via Chennai and provide cessation services by behavioral therapy. Methods: This cross-sectional study was conducted by a dental screening team who were involved in data collection and screening of the 747 truck drivers who fulfilled the inclusion and exclusion criteria between Jan to Oct 2022. After data collection, oral examinations were done and suspicious lesions were sought for expert opinion. A standard punch biopsy was taken from those lesions requiring confirmation. Results: Among the 747 subjects who participated in this program, 704 (94.2%) were current users of various tobacco products, with 235 (31.4%) preferring smoking and the rest 469(62.8%) using smokeless tobacco products. Oral mucosal lesions were recorded in 49 (6.5%) of the study population, mostly among tobacco users. Punch/incisional biopsies were taken among 17 of the 49 subjects and oral dysplasia was histopathologically confirmed in 9 (mild epithelial dysplasia = 5; moderate epithelial dysplasia = 4) subjects.  Conclusion: Truck drivers with tobacco and substance abuse are at high risk of developing oral cancer and hence this study emphasizes the importance of periodic oral cancer screening programs for this vulnerable population to identify potentially malignant oral lesions at an early stage
    corecore