186 research outputs found
AN INVESTIGATION OF SECURITY CHALLENGES IN COGNITIVE RADIO NETWORKS
The recent advances in wireless communication have led to the problem of growing spectrum scarcity. The available wireless spectrum has become scarcer due to increasing spectrum demand for new wireless applications. The large portion of the allocated spectrum is sporadically used leading to underutilization of significant amount of spectrum. To improve the spectrum efficiency, the idea of cognitive radio technology was introduced. This concept of cognitive radio provides a promising solution for the spectrum scarcity issues in wireless networks. Meanwhile, the security issues of cognitive radio have received more attentions recently since the inherent properties of CR networks would pose new challenges to wireless communications. In this MS thesis, general concepts of security threats to the cognitive radio networks are briefly reviewed. Performances for primary user emulation attacks are studied from Neyman-Pearson criterion point of view. A novel system model with different configurations of the primary users has been proposed and studied. Our experimental results demonstrate the statistical characteristics of the probability of false alarm and miss detection in the proposed system. I will make performance comparison with othersâ research in the future.
Adviser: Yaoqing Yan
AN INVESTIGATION OF SECURITY CHALLENGES IN COGNITIVE RADIO NETWORKS
The recent advances in wireless communication have led to the problem of growing spectrum scarcity. The available wireless spectrum has become scarcer due to increasing spectrum demand for new wireless applications. The large portion of the allocated spectrum is sporadically used leading to underutilization of significant amount of spectrum. To improve the spectrum efficiency, the idea of cognitive radio technology was introduced. This concept of cognitive radio provides a promising solution for the spectrum scarcity issues in wireless networks. Meanwhile, the security issues of cognitive radio have received more attentions recently since the inherent properties of CR networks would pose new challenges to wireless communications. In this MS thesis, general concepts of security threats to the cognitive radio networks are briefly reviewed. Performances for primary user emulation attacks are studied from Neyman-Pearson criterion point of view. A novel system model with different configurations of the primary users has been proposed and studied. Our experimental results demonstrate the statistical characteristics of the probability of false alarm and miss detection in the proposed system. I will make performance comparison with othersâ research in the future.
Adviser: Yaoqing Yan
Malignant nodular hidradenoma-inguinal region clinically masquerading as squamous cell carcinoma: a case report
Malignant Nodular hidradenoma is an extremely rare aggressive tumour originating from eccrine sweat glands with an incidence of <.001%. So far less than 80 cases have been reported in the literature. Itâs known for its local recurrence (50%) and metastasis (60%) and hence early diagnosis and radical treatment is mandatory. But differentiating it from its benign counterparts and other skin tumour mimics is challenging, due to its histopathological similarity & lack of diagnostic immunomarkers. Authors report a case of 65-year-old female who presented with a short 4-month history of rapidly growing ulceroproliferative growth in the right inguinal region with bilateral inguinal node enlargement, associated with pain and discharge. Wedge biopsy of left inguinal lymph node showed malignant cutaneous adnexal tumour deposits, which after excision was typed as malignant nodular hidradenoma. It was confirmed with immunohistochemistry. Patient presented with recurrence 8 months after excision
Fluxes of heat and momentum over sea surface during the passage of Ă” depression in the north Bay of Bengal
Tims variation of surface Fluxes of heat, moisture and momentum over a sea station (20:N89E) in the norm Bay of Bengal Mas been computed bv srofiie method lor the Period IK;:-, 25th Angus; 1990 using meteorological data of MOSTBL EX-90 from OR Y Sayarkniyii. The fluxes showed synoptic and uiurnal variations nnich ars rrarked during oppression (20th-21st August) comparée to their variation prior to and after tais period. Variations of heal and water vapour fluxes were in phase. Nigh- time fluxes are ralati.eiy high ccmpared to day time. Average ir.orner.tam transfer during depressor. two io three times large. Variations in Bowen ratio wers relatively large during day time. During depression, it varied between 0-2 in day lime and about 00 A., nignt and in the undisturbed period between 0-1 jnd 0-2 during day time and 0-2 and 025 at nigh:. The study shows that the assumption of the exchange coefficients normaiiy used ir. estimating the Ruxes by the buk Lu-rodyr.umic method is not appropriate because Cy/C- C and CH/C14
A clinico-pathological study of lichenoid tissue reactions/interface dermatitis
Background: Lichenoid tissue reaction/Interface dermatitis (LTR/ID) refers to a number of clinically diverse, poorly understood and relatively uncommon inflammatory skin diseases. This study was done to understand the histopathological features of lichenoid tissue reactions in skin biopsies and to assess the concordance and disparity between the clinical and histopathological diagnosis of variants of the same.Methods: It was a 3œ years study from January 2014 to June 2017 in the department of Pathology, KIMS, Hubballi. The present study included skin biopsies of clinically diagnosed and suspected cases and histologically diagnosed cases of LTRs. Skin biopsies received were routinely paraffin processed and H&E stained to study the microscopic features.Results: Out of 166 skin biopsies studied, 148 were histologically confirmed as LTR with majority being of lichen planus (LP) (91.22%). Classical lichen planus was the most common variant of lichen planus among lichen planus cases. Male:female ratio was 1.2:1. Clinico-pathological concordance was seen in 88.55% of the cases.Conclusions: Though definite diagnosis can be made on histopathological examination, size of specimen, site of biopsy, nature and depth of biopsy, quality of sections, treatment history and inter-observer variation (both clinically and histologically) should be kept in mind which may lead to clinicopathological discordance
Parachordoma: a rare recurring case at a rare site
Parachordoma is an uncommon tumor of soft tissue and the orign is not clear. This soft tissue tumor resembles chordomas as well as extraskeletal myxoid chondrosarcomas and has only recently been fully characterized. Although it is considered a benign lesion, its behavior tends to be locally aggressive, with reports of a recurrence rate of up to 20% and of several cases of metastasis. In this article, we report a case of parachordoma in the neck with recurrence that we met in clinical works
Preconception nutrition intervention improved birth length and reduced stunting and wasting in newborns in south Asia: The women first randomized controlled trial
South Asia has \u3e50% of the global burden of low birth weight (LBW). The objective was to determine the extent to which maternal nutrition interventions commenced before conception or in the 1st trimester improved fetal growth in this region. This was a secondary analysis of combined newborn anthropometric data for the South Asian sites (India and Pakistan) in the Women First Preconception Maternal Nutrition Trial. Participants were 972 newborn of mothers who were poor, rural, unselected on basis of nutritional status, and had been randomized to receive a daily lipid-based micronutrient supplement commencing â„3 months prior to conception (Arm 1), in the 1st trimester (Arm 2), or not at all (Arm 3). An additional protein-energy supplement was provided if BMI/m2 or gestational weight gain was less than guidelines. Gestational age was established in the 1st trimester and newborn anthropometry obtaine
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Early pregnancy loss in Belagavi, Karnataka, India 2014â2017: a prospective population-based observational study in a low-resource setting
Background
The prevalence of early pregnancy loss through miscarriage and medically terminated pregnancy (MTP) is largely unknown due to lack of early registration of pregnancies in most regions, and especially in low- and middle-income countries. Understanding the rates of early pregnancy loss as well as the characteristics of pregnant women who experience miscarriage or MTP can assist in better planning of reproductive health needs of women.
Methods
A prospective, population-based study was conducted in Belagavi District, south India. Using an active surveillance system of women of childbearing age, all women were enrolled as soon as possible during pregnancy. We evaluated rates and risk factors of miscarriage and MTP between 6 and 20Â weeks gestation as well as rates of stillbirth and neonatal death. A hypothetical cohort of 1000 women pregnant at 6Â weeks was created to demonstrate the impact of miscarriage and MTP on pregnancy outcome.
Results
A total of 30,166 women enrolled from 2014 to 2017 were included in this analysis. The rate of miscarriage per 1000 ongoing pregnancies between 6 and 8Â weeks was 115.3, between 8 and 12Â weeks the miscarriage rate was 101.9 per 1000 ongoing pregnancies and between 12 and 20Â weeks the miscarriage rate was 60.3 per 1000 ongoing pregnancies. For those periods, the MTP rate was 40.2, 45.4, and 48.3 per 1000 ongoing pregnancies respectively. The stillbirth rate was 26/1000 and the neonatal mortality rate was 24/1000. The majority of miscarriages (96.6%) were unattended and occurred at home. The majority of MTPs occurred in a hospital and with a physician in attendance (69.6%), while 20.7% of MTPs occurred outside a health facility. Women who experienced a miscarriage were older and had a higher level of education but were less likely to be anemic than those with an ongoing pregnancy at 20Â weeks. Women with MTP were older, had a higher level of education, higher parity, and higher BMI, compared to those with an ongoing pregnancy, but these results were not consistent across gestational age periods.
Conclusions
Of women with an ongoing pregnancy at 6Â weeks, about 60% will have a living infant at 28Â days of age. Two thirds of the losses will be spontaneous miscarriages and one third will be secondary to a MTP. High maternal age and education were the risk factors associated with miscarriage and MTP.
Trial registration
The trial is registered at clinicaltrials.gov. ClinicalTrial.gov Trial Registration:
NCT01073475
Duration of third stage labour and postpartum blood loss: a secondary analysis of the WHO CHAMPION trial data
Background: Obstetric haemorrhage continues to be a leading cause of maternal mortality, contributing to more than a quarter of the 2,443,000 maternal deaths reported between 2003 and 2009. During this period, about 70% of the haemorrhagic deaths occurred postpartum. In addition to other identifiable risk factors for greater postpartum blood loss, the duration of the third stage of labour (TSL) seems to be important, as literature shows that a longer TSL can be associated with more blood loss. To better describe the association between the duration of TSL and postpartum blood loss in women receiving active management of third stage of labour (AMTSL), this secondary analysis of the WHO CHAMPION trial data has been conducted. Methods: This was a secondary analysis of the WHO CHAMPION trial conducted in twenty-three sites in ten countries. We studied the association between the TSL duration and blood loss in the sub cohort of women from the CHAMPION trial (all of whom received AMTSL), with TSL upto 60 min and no interventions for postpartum haemorrhage. We used a general linear model to fit blood loss as a function of TSL duration on the log scale, arm and center, using a normal distribution and the log link function. We showed this association separately for oxytocin and for Heat stable (HS) carbetocin. Results: For the 10,040 women analysed, blood loss rose steeply with third stage duration in the first 10 min, but more slowly after 10 min. This trend was observed for both Oxytocin and HS carbetocin and the difference in the trends for both drugs was not statistically significant (p-value = 0.2070). Conclusions: There was a positive association between postpartum blood loss and TSL duration with either uterotonic. Blood loss rose steeply with TSL duration until 10 min, and more slowly after 10 min.Fil: Chikkamath, Sumangala B.. S. Nijalingappa Medical College; IndiaFil: Katageri, Geetanjali M.. S. Nijalingappa Medical College; IndiaFil: Mallapur, Ashalata A.. S. Nijalingappa Medical College; IndiaFil: Vernekar, Sunil S.. Jawaharlal Nehru Medical College Belgaum; IndiaFil: Somannavar, Manjunath S.. Jawaharlal Nehru Medical College Belgaum; IndiaFil: Piaggio, Gilda. No especifĂca;Fil: Carroli, Guillermo. Centro Rosarino de Estudios Perinatales; ArgentinaFil: de Carvalho, JosĂ© Ferreira. No especifĂca;Fil: Althabe, Fernando. Organizacion Mundial de la Salud; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Centro de Investigaciones en EpidemiologĂa y Salud PĂșblica. Instituto de Efectividad ClĂnica y Sanitaria. Centro de Investigaciones en EpidemiologĂa y Salud PĂșblica; ArgentinaFil: Hofmeyr, G. Justus. University of Botswana; Estados Unidos. University of the Witwatersrand; SudĂĄfricaFil: Widmer, Mariana. Organizacion Mundial de la Salud; ArgentinaFil: Gulmezoglu, Ahmet Metin. No especifĂca;Fil: Goudar, Shivaprasad S.. Jawaharlal Nehru Medical College Belgaum; Indi
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