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With the aid of a coherent transport model utilizing the non-equilibrium Green function approach, a three terminal device with metallic gate, source and drain and a quasi one dimensional charge density wave (CDW) channel is simulated focussing on the transistor behaviour brought about by a sweep of the channel potential or equivalently the chemical potential in the channel. The channel is strongly insulating only at half-filling and moving to lower and higher carrier concentrations both incur a mean field phase transition to a conducting state. With the aid of conductance calculations for a pinned CDW condensate, we present calculations for the sub-threshold slope in terms of the hopping parameter or equivalently the width of the tight-binding chain. The effects of source to drain bias and length are examined. The conductance profiles are analyed in relation to transmission profiles. The observed CDW profiles are explained in terms of filling and Fermi surface nesting. Boundary conditions, gap equations and response functions are shown to reveal the commensurability conditions and size of the transport gap. The channel carrier concentration is modulated in an athermal (non-Maxwellian-Boltzmann) fashion, thereby making it an interesting prospect for steep transistors.

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Sacroiliac (SI) joint dysfunction is a common source of chronic low-back pain. Recent evidences from different parts of the world suggest that cooled radiofrequency (RF) neuroablation of sacral nerves supplying SI joints has superior pain alleviating properties than available existing treatment options for SI joint dysfunctional pain. A 35-year-old male had intractable bilateral SI joint pain (numeric rating scale [NRS] - 9/10) with poor treatment response to intra-articular steroid therapy. Bilateral water cooled = RF was applied for neuroablation of nerves supplying both SI joints. Postprocedure pain intensity was 5/10 and after 7 days it was 2/10. On 18th-month follow-up, he is pain free except for mild pain (NRS 2/10) on occasional extreme twisting of the back. This case attempts to highlight that sacral neuroablation based on cooled RF technique can be a long lasting remedial option for chronic SI joint pain unresponsive to conventional treatment.

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BACKGROUND: Eclampsia is a very serious complication of pregnancy which is responsible for high maternal and perinatal mortality. Worldwide, it accounts for 50,000 maternal deaths annually. In spite of several global and regional interventions and initiatives from governments and other concerned agencies, maternal mortality is still very high in India, with eclampsia as a major cause. This study was conducted to determine the mode of deaths and incidence of maternal mortality associated with eclampsia and to assess how socio-demographic and clinical characteristics of the women influence the deaths. MATERIALS AND METHODS: This is a retrospective study of 111 eclampsia related maternal deaths over a period of 5 years from January 2008 to December 2012. Data pertaining to their age, parity, booking status, gestational age at delivery, and time interval from admission to death were also obtained from the records for analysis. RESULTS: Eclampsia accounted for 43.35% of total maternal deaths, with case fatality of 4.960%. The commonest mode of death in eclampsia is pulmonary oedema. Death due to eclampsia commonly occurs in younger age group of 19-24 years and in primi gravid. Eclampsia related deaths were mostly seen in illiterate and unbooked cases. Maternal deaths were also very common in lower socio economic status. CONCLUSION: Eclampsia still remains the major cause of maternal mortality in this region resulting from unsupervised pregnancies and deliveries. There is a need to educate and encourage the general public for antenatal care and hospital delivery by which we can defeat this powerful enemy.

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BACKGROUND: Surgery and endotracheal intubation both causes an increase in metabolic stress response. This is further aggravated during laparoscopic surgeries. In this study we aimed at comparing hemodynamic and metabolic parameters which are reflective of intraoperative stress response while using I-GEL against endotracheal tube (ETT) during laparoscopic cholecystectomy. MATERIAL AND METHODS: This is a prospective randomized comparative study among 64 cases of American Society of Anesthesiologists(ASA) physical status class I and II, undergoing laparoscopic cholecystectomy who were randomly allocated into two groups of 32 each using computer generated random number table. Patients were put under general anesthesia using standard protocol. After anesthesia induction and 20 minutes after induction venous blood samples were obtained for measuring adrenalin, noradrenalin, dopamine and cortisol levels. Hemodynamic and respiratory parameters were recorded at the 1st, 5th, 15th, 30th and 45th minutes after the insertion of airway device. RESULTS: Although there was no significant difference regarding ventilatory parameters there was significant increase in heart rate at 1st and 45th minutes (p = 0.02 and 0.034) respectively and increase in mean arterial pressure at 15th and 30th minutes(p = 0.034 and 0.026) respectively in the ETT group compared to I-GEL group. Stress hormone intergroup analysis revealed significant increase in serum cortisol 20 minutes after induction in ETT group as compared to I-GEL group (p = 0.03). CONCLUSION: I-GEL usage is a suitable, effective and safe alternative to ETT in laparoscopic cholecystectomy patients with lower metabolic stress response.

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BACKGROUND: Apha-2 agonists are combined with local anesthetics to extend the duration of regional anesthesia. We evaluated the effect of combining dexmedetomidine with levobupivacine with respect to duration of motor and sensory block and duration of analgesia. METHODS: Sixty patients scheduled for elective forearm and hand surgery were divided into two equal groups in a randomized double blind fashion. The patients received brachial plexus block via supraclavicular route with the help of nerve stimulator. In group L (n=30) 35cc of levobupivacaine with 1ml of isotonic saline and in group LD (n=30) 35cc of levobupivacine with 1 ml of (100 microgram) of dexmedetomidine was given. Duration of motor and sensory block and time to first rescue analgesia were recorded. Data analysis was done by SPSS version 16.0 [SPSS Inc ILLINOIS, USA, 2008]. Categorical variables were analyzed using Pearson"s Chi-square test. Normally distributed numerical variables were analyzed using unpaired "t" test. Skewed numerical variables within the group were analyzed using Man-Whitney "U" test. All tests were two tailed. Statistical significance was defined as P<0.05. RESULTS: Sensory and motor block durations were longer in group LD as compared to L (P<0.01). Duration of analgesia was significantly longer in group LD as compared to group L (p<0.05). CONCLUSION: Dexmedetomidine added to levobupivacaine in supraclavicular brachial plexus block prolongs the duration of block and the duration of postoperative analgesia.

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