A SURVEY OF IMPLEMENTATION OF OPPORTUNISTIC SPECTRUM ACCESS ATTACK WITH ITS PREVENTIVE SENSING PROTOCOLS IN COGNITIVE RADIO NETWORKS

Recently, the expansive growth of wireless services, regulated by governmental agencies assigning spectrum to licensed users, has led to a shortage of radio spectrum. Since the FCC (Federal Communications Commissions) approved unlicensed users to access the unused channels of the reserved spectrum, new research areas seeped in, to develop Cognitive Radio Networks (CRN), in order to improve spectrum efficiency and to exploit this feature by enabling secondary users to gain from the spectrum in an opportunistic manner via optimally distributed traffic demands over the spectrum, so as to reduce the risk for monetary loss, from the unused channels. However, Cognitive Radio Networks become vulnerable to various classes of threats that decrease the bandwidth and spectrum usage efficiency. Hence, this survey deals with defining and demonstrating framework of one such attack called the Primary User Emulation Attack and suggests preventive Sensing Protocols to counteract the same. It presents a scenario of the attack and its prevention using Network Simulator-2 for the attack performances and gives an outlook on the various techniques defined to curb the anomaly

A study of serum electrolytes in severe acute malnourished children with and without complications

Objective: Children with severe acute malnutrition (SAM) are categorized into “complicated and uncomplicated cases” based on clinical criteria alone. Electrolyte imbalance is one of the prognostic factors in severe malnutrition. We aimed to study serum electrolytes in complicated and uncomplicated SAM children. Methods: This was a cross-sectional observational study conducted at the nutritional rehabilitation center of a tertiary care hospital attached to a medical college from May 2016 to April 2017. Children between the ages of 1 month and 5 years who met the World Health Organization criteria for SAM were included in the study. Serum electrolytes were estimated with an automated analyzer by ion selective electrode method. Results: Among 113 SAM children included, 71 had complications and 42 were without complications. The mean value of serum sodium was 134.58±5.45 meq/L, potassium was 4.29±0.75 meq/L, and chloride was 103.31±7.16 meq/L. Hyponatremia was seen in 43.4% and hypokalemia in 7.1% of children. There was no statistically significant difference in the mean values of serum electrolytes and frequency of hyponatremia and hypokalemia between groups. Conclusion: Dyselectrolytemia occurs in SAM children with and without complications. Serum electrolyte levels may need to be measured in all SAM cases to detect asymptomatic hyponatremia and hypokalemia. This will help in triaging those with asymptomatic hyponatremia and hypokalemia to inpatient care

Bronchial Artery Embolisation in Hemoptysis

Massive hemoptysis, defined as an expectoration of more than 300 ml of blood in a day1, has a very high mortality when left untreated2. The management of massive hemoptysis and recurrent non-massive hemoptysis( expectoration of > 100 ml of blood in a day for a few days or weeks) includes surgical and endovascular treatment. Most commonly, these patients suffer from diffuse interstitial lung disease or chronic granulomatous disease such as cystic fibrosis, interstitial pulmonary fibrosis, bronchiectasis, tuberculosis, and fungal infections such as aspergillosis. Less common causes of massive hemoptysis include aneurysms, arteriovenous fistulae, pulmonary embolism, and neoplasms ranging from small benign endobronchial lesions to large malignant tumors. Endovascular management in bleeding states has established itself as a promising and effective treatment modality. Bronchial artery embolization (BAE) is an ideal first-line treatment because actively bleeding patients with poor underlying pulmonary function tend to be poor surgical candidates. In addition, unlike surgical resection, BAE often preserves pulmonary function. BAE was first described by Remy in 19733. Since then, the procedure has proven its safety and effectiveness in controlling hemoptysis in diverse lung conditions in different studies 4-7

Primary Sjögren\u27s Syndrome Presenting as Cerebral Venous Thrombosis: A Rare Case

Sjogren\u27s syndrome is a late-onset, slowly progressing autoimmune disease characterized by the destruction of the exocrine glands by lymphocytic infiltration, resulting in dry mouth (xerostomia) and dry eyes (keratoconjunctivitis sicca). Sjögren\u27s syndrome may be associated with various autoimmune diseases, including systemic lupus erythematosus, rheumatoid arthritis, and systemic sclerosis. We report a case of a 34-year-old female who delivered a live baby 20 days ago. She presented in a postictal state after two episodes of tonic-clonic movements of limbs with altered sensorium with a history of headache for seven days. Further evaluation revealed that the subject had a history of multiple abortions and grittiness in her eyes. MRI showed signs of infarction in the left parietal lobe and magnetic resonance venography (MRV) suggested cavernous venous thrombosis. After an unwavering effort to rule out alternate causes, the rare correlation between primary Sjogren\u27s syndrome and cerebral venous thrombosis was considered. Additional investigations were performed, which showed the patient to be positive for Anti SS-A (Ro52), Anti SS-B (La), and anti-centromere antibodies. The patient gradually improved with anti-edema measures and steroids and was discharged by day nine. We present this case to emphasize the neurological manifestation of Sjogren\u27s syndrome, which may present as cerebral venous thrombosis