On Dynamic Optimality for Binary Search Trees

Does there exist O(1)-competitive (self-adjusting) binary search tree (BST) algorithms? This is a well-studied problem. A simple offline BST algorithm GreedyFuture was proposed independently by Lucas and Munro, and they conjectured it to be O(1)-competitive. Recently, Demaine et al. gave a geometric view of the BST problem. This view allowed them to give an online algorithm GreedyArb with the same cost as GreedyFuture. However, no o(n)-competitive ratio was known for GreedyArb. In this paper we make progress towards proving O(1)-competitive ratio for GreedyArb by showing that it is O(\log n)-competitive

Ecopharmacology: an issue that needs urgent action

In recent years great concern has been expressed over the potential impact of pharmaceuticals in the environment. Pharmaceutical from various therapeutic classes have increasing being detected in the environment typically at low concentration in surface water. This has lead to development of ecopharmacovigilance (EPV). World Health Organization (WHO) defines eco pharmacovigilance as the science and activities associated with the detection, evaluation, understanding, and prevention of adverse effects of pharmaceuticals in the environment. Compared to the west EPV in India is still in infancy, there is no formal frame-work to monitor for potential adverse effects of the pharmaceuticals on the environment

To introduce and measure the effectiveness of case based learning in physiology

Background: Student/learner centered strategies are needed to promote active learning in the students. Medical Council of India (MCI) also encourages learner centric approaches. Objectives of the study were to develop case scenarios for teaching in Physiology and use them to teach 1st professional MBBS students and to evaluate the impact of this intervention on students’ learning.Methods: After the approval from Institutional Ethics Committee (IEC) the study was conducted on MBBS 1st professional students. The students were taught two topics using CBL strategy. Pre-post test score were taken for evaluation of students’ learning. Students’ feedback was taken to elicit their perceptions about the effectiveness of the strategy. Faculty feedback was also taken for feasibility and implementation of CBL.Results: Majority of the students were satisfied with the session. Majority felt it to be a good learning experience and many wanted to attend more such sessions. Difference in the pre-post test scores was statistically highly significant.Conclusions: CBL proved to be an interesting and effective active learning strategy. More of such sessions should be conducted to engage the students as felt by students and faculty both

Quality of Service Provisioning in Manet Using a Cross-Layer Approach for Routing

Deployment of multimedia applications warrants provisioning of Quality of Service (QoS) in MANET. However, limited battery power, other resource constraints and mobility of nodes make QoS provisioning difficult to achieve in MANET. This difficulty can be overcome by using a cross-layer approach for routing. In [1] Patil et al., proposed a cross-layer routing protocol named Cost Based Power Aware Cross Layer - AODV (CPACL-AODV) which overcomes the limitation of battery power of nodes. Though many similar energy efficient and cross-layer routing protocols have been proposed for MANET, none of them handles QoS. A novel MANET routing protocol, Type of Service, Power and Bandwidth Aware AODV (TSPBA-AODV), which overcomes resource constraints and simultaneously provides QoS guarantees using a cross-layer approach, is proposed in this paper. In addition the effect of variation in nodes' mobility on performance of TSPBA-AODV is compared with that of CPACL-AODV [1] for two different types of network traffic. As shown by the results of simulations performed, TSPBA-AODV performs better than CPACL-AODV for MANET in which nodes move with small speeds (speeds up to 40 Km/hr approx.). In addition the effect of variation in data sending rate of nodes on performance of the protocols is also studied. As shown by the results of simulations performed, TSPBA-AODV performs better than CPACL-AODV for all variations in data sending rate of nodes.Comment: 12 pages, 12 figure

Formulation and Evaluation of Itraconazole Niosomal Gel for Topical Application

Niosomes have potential applications in topical drug delivery system. Niosomes play an increasingly important role in drug delivery as they can reduce toxicity and modify pharmacokinetic and bio-availability. Topically applied niosomes can increase the residence time of drugs in the stratum corneum and epidermis, while reducing the systemic absorption of the drug. It can act as drug containing reservoirs and the modification of the vesicular compositions or surface properties can adjust the drug release rate and the affinity for the target site. Itraconazole is a triazole derivative useful in the treatment of number of fungal infections. This includes aspergillosis, blastomycosis, coccidioidomycosis, histoplasmosis, and paracoccidioidomycosis. It may be given by mouth or intravenously. Itraconazole niosomes were prepared by thin film hydration method using span 20, 40, 60 (as non-ionic surfactant) and cholesterol (as stable vesicle forming agent). Niosomes were prepared using different ratio of drug: surfactant: cholesterol (1:1:1, 1:2:1, 1:3:1). The niosomal dispersion was evaluated for vesicle size, surface morphology, percent entrapment efficiency, drug content and in vitro drug release. The entrapment efficiency and drug content were calculated at 262 nm using UV spectrophotometer. The entrapment efficiency was found to be 57.2%, 73.2% and 61.2% for the formulations ITZ 20-3, ITZ 40-2 and ITZ 60-1. Itraconazole niosomal gel was prepared using Carbopol 940, glycerol, Triethanolamine and distilled water. Evaluation of niosomal gel was determined by physical appearance, pH, viscosity, drug content, entrapment efficiency and In-vitro permeation studies. The percentage of the drug release from the niosomal gel was found to be 55.67 % for ITZG-2. The present study demonstrates prolongation of drug release, an increase in amount of drug retention into skin and improved permeation across the skin after encapsulation of Itraconazole into niosomal topical gel. Keywords: Niosomes, Itraconazole, Fungal infection, Thin film hydration method, Carbopol 94

Evaluation of propranolol, flunarizine and divalproex sodium in prophylaxis of migraine

Background: Preventive treatment has an important role in the management of migraine. Propranolol and flunarizine have been used for more than two decades while, open-label, controlled studies suggest divalproex sodium may also be efficacious for migraine prevention. The objective of the study to compare efficacy and safety of propranolol, flunarizine and divalproex sodium in patients for migraine prophylaxis.Methods: Following approval from IEC a 12-week randomized, open, comparative study was carried out at the outpatient department of Medicine. Patients between 18 to 65 years, with history of 3 to 12 migraines a month (IHS) for six months were included. Patients were divided into three groups of 30 patients to receive - propranolol 20 to 160mg/day; flunarizine 5 to 10mg/day or divalproex sodium 250 to 750mg/day, for three months.Results: Total 90/116 patients completed the study. No significant differences were found between the groups with regards to mean age or other baseline migraine features. All the drugs significantly decreased the frequency, duration and severity of migraine (P<0.001). There is no statistically significant difference between propranolol, flunarizine and divalproex sodium for any of the efficacy parameters. All the three treatments were well-tolerated and safe.Conclusions: All the three study drugs were equally effective with an acceptable tolerability profile, Divalproex sodium group showed more side effects, none of which were serious. However, further studies with larger number of patients and longer duration of treatment are recommended

Assessing the factors that influence a recurrence of congenital talipes equinovarus in children treated with the Ponseti method

Background: Congenital talipes equinovarus, also known as clubfoot, is one of the most common congenital malformations in pediatric orthopedics. With a checkered treatment history extending from Hippocrates' bandages to Kite's serial plaster cast application to surgical treatment, no single modality can claim to be a complete treatment. Methods: In a combined prospective and retrospective study at the Department of Orthopaedics of St. Stephen's Hospital, 192 patients with 292 clubfeet who met the inclusion criteria and received ethics committee approval were included. The purpose of the research was to identify early recurrence characteristics, undertake the Pirani scoring, and identify additional clinical characteristics to evaluate recurrence predictors. Results: In our study, out of 192 patients, 188 were successfully treated with the Ponseti casting technique combined with tendoachilles tenotomy; tenotomy was required in 177 patients (93%). Four patients were lost to follow-up. Nine out of sixty-one children in the six-month-to-one-year age group showed the maximum rate of recurrence (15%). The mean number of cast applications was 7.23. In all, 90% of children required casts ranging from four to eight in number. The syndromic association was seen in 10.4% of cases with club feet. Most common among them were neural tube defects (4.2%) and arthrogryposis (3% of cases). Fourteen out of 154 (or 9%) of the non-operated idiopathic patients had lateral border recurrence during an average follow-up of two years. According to the Pirani score, recurrence was seen in eight out of twenty (or 40% of) syndromic patients and five out of fourteen (or 35% of) operated cases. In 37% of recurrences, dynamic supination was observed. Conclusions: Even though Ponseti's approach to treating idiopathic clubfoot is widely regarded as the gold standard, recurrences are known to occur even in the best of circumstances. The most common cause of recurrence was poor brace compliance, with families citing a variety of reasons

An Unusual And Intriguing Presentation Of Sydenham’s Chorea

A 26-year-old male born of a non-consanguineous marriage with normal birth and developmental history presented with abnormal movements for the last 15 years. He first noticed changes in his handwriting. The movements were jerky, non-stereotyped, and were associated with violent flinging movements. They were not preceded by any premonitory urge and were only partially suppressible. The movements gradually progressed to involve the face and neck, and, over the next 5 years, became generalized. His parents also complained of behavioral disturbances such as hyperactivity, aggressiveness, and obsessive-compulsive behavior. There was no history of cognitive decline, psychosis, seizures, or myoclonic jerks. Family history was non-contributory. There was no history of rheumatic fever, vasculitis, or exposure to toxins. The patient suffered frequent throat infections until the age of 5 years. He had been previously prescribed multiple medications, without significant improvement (tetrabenazine, haloperidol, valproate, clonazepam in various combinations). This letter shows an unusual presentation of Sydenham’s chorea lasting more than 15 years and highlight the utility of antineuronal antibodies in such a scenario