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BACKGROUND: Early evidence suggests good response to pallidal deep brain stimulation (DBS) in DYT‐KMT2B. OBJECTIVES: We aimed to conduct a systematic review and meta‐analysis to assess outcomes and identify predictors of good outcome following GPi‐DBS in DYT‐KMT2B. METHODS: We searched MEDLINE, Cochrane and MDS‐abstracts databases using the MeSH terms “KMT2B and DYT28”. We included studies that reported objective outcomes following GPi‐DBS in DYT‐KMT2B. The BFMDRS‐M (Burke‐Fahn‐Marsden Dystonia Rating Scale‐ Movement) total scores pre‐ and post‐surgery were used to quantify outcomes. We calculated pooled effects using a random effects meta‐analysis and used meta‐regression to identify potential effect modifiers. Multiple linear regression using individual patient data was used to identify predictors of good outcome (>50% improvement from baseline on BFMDRS‐M). RESULTS: Initial searches screened 132 abstracts of which 34 full‐text articles were identified to be of potential interest. Ten studies reporting 42 individual patients, met the inclusion/exclusion criteria and were included in the final review. The mean age at onset was 6.4 ± 5.7 years and 40% were male. The median follow‐up was 12 months (range: 1–264 months). GPi‐DBS resulted in median BFMDRS‐M improvement of 42.7% (range: −103.5% to 95.9%) postoperatively. Pooled proportion of patients experiencing clinical improvement >50% on BFMDRS‐M was 41% (95% CI: 27%–57%). Male gender [β: 22.6, 95% CI: 8.0–37.3, P = 0.004), and higher pre‐operative BFMDRS‐M score [β: 0.62, 95% CI: 0.36–0.87, P

A 42-year-old Indian woman presented with a slowly progressive and painless swelling in the superomedial aspect of right orbit over past 5 years. She succumbed to homeopathic treatment which controlled the swelling for some time, but eventually recurred. The swelling led to protrusion of her right eye down and out. The patient's vision in her right eye was reduced, with restricted movement on elevation and adduction. The right eye pupil was sluggishly reacting to light. The fundus examination of the right eye revealed hyperemic disc with disc edema and retinal folds. Whereas, left ocular examination was normal. The computed tomography and magnetic resonance imaging scans of the right orbit revealed an intraconal, multiloculated lesion in the superomedial aspect of the orbit, adhering to the optic nerve, giving us an array of differential diagnosis. She underwent right anterolateral orbitotomy under general anesthesia; the masses excised were sent for histopathological examination, which gave the definitive diagnosis of a schwannoma.

Hashimoto’s encephalopathy (HE) commonly presents with two types of neurological presentation: recurrent stroke-like episodes or seizures and progressive cognitive decline. Being a treatable disorder, one cannot afford to miss the diagnosis. We report a female with HE who presented with a history of recurrent episodes of catatonia, recovering completely with steroids. The diagnosis of the primary disease got delayed for 5 months. HE presenting as catatonia has been reported rarely. A high degree of suspicion in appropriate clinical settings, resulting in early diagnosis, is rewarding as HE usually show good response to corticosteroids.

Medical training programs are witnessing immense disruptions worldwide due to the ongoing COVID-19 pandemic. Keeping in mind the trainees' future prospects, it is important to provide continuity of teaching and timely certification assessments. Overcoming the obstacles to routine functioning presented by SARS-CoV-2 spread, we recently conducted the DM Neurology exit examination in a hybrid virtual format. We created a curated case repository with history and clinical examination findings followed by structured questions that could be built upon for case discussions. The external examiners assessed the candidates virtually through a video conferencing platform. The end results were well accepted by all key stake holders. The concerns, logistics and experience of conducting the DM Neurology exit exam in a virtual format are summarized here.

Background and Aims: Anaesthetised patients, when positioned prone, experience hypotension and reduction in cardiac output. Associated autonomic dysfunction in cervical myelopathy patients predisposes them to haemodynamic changes. The combined effect of prone positioning and autonomic dysfunction in anaesthetised patients remains unknown. Methods: Thirty adult chronic cervical myelopathy patients, aged 18-65 years with Nurick grade ≥2 were recruited in this prospective observational study. Heart rate, mean blood pressure, cardiac output, stroke volume, total peripheral resistance and stroke volume variation were measured using NICOM®monitor. Data were collected in supine before anaesthetic induction (baseline), 2 minutes after induction, 2 minutes after intubation, before and after prone positioning and every 5 minutes thereafter until skin incision. Repeated measures analysis of variance (ANOVA) was used to analyse the haemodynamic parameters across the time points. Bivariate Spearman's correlation was used to find factors associated with blood pressure changes. A P value

Background: Movement disorders are one of the prominent nonataxic symptoms in patients of spinocerebellar ataxia (SCA). The type of movement disorder may provide clinical clue to the type of SCA. Objective: The objective of this study is to evaluate various movement disorders in patients of genetically proven SCAs and to establish a probable clinico-genetic correlation. Methods: Ninety-Five patients of genetically proven SCAs were assessed for the presence of various movement disorders. Results: Patients with SCA (75.8% males) with at least one movement disorder contributed 43.16%. Age for onset of movement disorder was 43.39 ± 13.43 years. SCA-12 (38.95%) was the most common subtype. Among the patients with at least one movement disorder, action tremor of hands contributed majority (90.2%). Dystonia and parkinsonism were present in 17.07% and 12.2% of patients (with movement disorder), respectively. Action tremor of hands was present in 34 patients with SCA-12 (91.89%), and 20 patients (54.05%) had onset of hand tremor preceding the onset of ataxia. Majority of patients with SCA-12 (81%) were of the same ethnic origin belonging to Agrawal community. Patients with movement disorder had a later onset (45 ± 13.88 years) of ataxic symptoms compared to those without a movement disorder (32.8 ± 11.92) (P =

Proximal balloon occlusion prior to carotid artery stenting is considered a relatively safe practice during endovascular treatment of carotid artery stenosis. Transient neurological deterioration affecting the ipsilateral hemisphere is seen soon after balloon inflation, when placed proximal to the stenotic segment. This occurs in cases of bilateral carotid disease due to insufficient collateral blood flow from the contralateral side. Near infrared spectroscopy cerebral oximetry (NIRS) is a valuable tool in detecting hypoperfusion- induced cerebral tissue desaturation (rSO2) during these procedures. This helps the interventional radiologist to deflate the balloon at the earliest to re-establish the cerebral blood flow. The non-invasive nature and continuous real-time interpretation make NIRS an attractive adjunct in the neuroanesthesiolgist's armamentarium for monitoring cerebral ischemia. However, significant contribution from chromophores in the extra-cerebral tissues and external carotid artery circulation can limit its sensitivity during occlusion of the internal carotid artery. In our case, it did not reflect brain ischemia during hypotension and when the neurologic symptoms were obvious. Commonly available cerebral oximetry sensors placed over the frontal region do not cover the parietal lobe where ischemia is likely to occur during occlusion of the carotid artery. In such scenarios, it has been shown that multi-channel NIRS has a better sensitivity in detecting cerebral ischemia. This case report highlights the importance of frequent neurological examination during carotid stenting as rSO2 values might not always suggest cerebral ischemia.

BACKGROUND: Hemi masticatory spasm (HMS) is a rare movement disorder affecting muscles of mastication attributed to dysfunction of motor branch of trigeminal nerve and is characterized by painful spasm of masticatory muscles. Microvascular compression leading to focal demyelination of motor branch of trigeminal nerve is the most speculated on mechanism of HMS. Treatment options range from medical to surgical approaches, but botulinm toxin (BTX) has now become the preferred treatment. CASES: We report a retrospective review of 7 cases of HMS, supported by electrophysiological and clinical findings. All the cases had excellent response to BTX therapy. DISCUSSION AND CONCLUSION: In this article, we highlight the delay in diagnosis of HMS attributed to rarity, long course of illness, association with hemiatrophy, “Lichen Sclerosus et Atrophicus,” and scleroderma/morphea. Considering the favorable outcome to BTXs, surgical treatment can be avoided or delayed in majority except secondary cases.

Background: Polymorphisms of the IL28B gene (rs12979860 and rs8099917) have been shown to impact treatment responses in hepatitis C virus (HCV) infected patients. The association of these polymorphisms with sustained viral response (SVR) has been studied in HCV genotype 3 infected patients in India, but not in genotype 1. Objectives: This study aimed to determine the association of IL28B gene polymorphisms and other host and viral factors with treatment response in patients with HCV genotype 1 and 3 infection. Materials and Methods: DNA from 42 HCV-infected patients on antiviral therapy was analysed for the IL28B polymorphisms using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Bidirectional sequencing was performed on a subset of samples for verification of PCR-RFLP results. Information on age, weight, height, diabetic status, pre-treatment viral load and alanine aminotransferase (ALT) levels was obtained from clinical records. The IL28B genotypes and the other factors were analysed for their association with SVR. Results: The frequency distribution of rs12979860 CC/CT/TT genotypes was found to be 66.7%, 26.2% and 7.1%, respectively. For rs8099917 genotype, the TT/GT/GG distribution was 73.8%, 21.4% and 4.8%, respectively. SVR was seen in 61.9% of cases (55.6% in genotype 1 and 62.5% in genotype 3). CC genotype at rs12979860 and TT genotype at rs8099917 were significantly higher in responders (P = 0.013 and 0.042, respectively). Lower baseline ALT and rapid viral response were also found to be associated with SVR. On logistic regression analysis, CC genotype at rs12979860 emerged as the most powerful predictor of treatment response. Conclusion: IL28B polymorphisms are strong predictors of SVR in patients from the Indian subcontinent infected with HCV genotype 3 and genotype 1.

Mother to child transmission of hepatitis B virus (HBV) is an important public health issue. India introduced HBV vaccine in 10 states as part of its Universal Immunization Program (UIP). Here we show evidence of mother-to-child transmission of HBV in three families from Jharkhand and Bihar states where HBV vaccination is not yet included in the UIP. This report illustrates the need for active screening of HBV in pregnant women and implementation of HBV vaccine across all states in India to reduce the burden of disease.

Although the p53 tumor suppressor is most frequently inactivated by genetic mutations, exclusion from the nucleus is also seen in human tumors. We have begun to examine p53 nuclear importation by isolating a series of mutant cells in which the temperature-sensitive murine p53Val135 mutant is sequestered in the cytoplasm. We previously showed that that three of them (ALTR12, ALTR19, and ALTR25) constituted a single complementation group. Here, we found that ALTR12 cells are more sensitive to heat stress than either ALTR19 or ALTR25 and that there was a complete lack of induction of Hsp70 in response to heat shock. Western blot analysis showed no expression of the Hsf1 transcription factor, and neither heat shock nor azetidine could induce p53 nuclear localization in ALTR12 cells but did in parental A1–5 cells. Suppression of Hsf1 in A1–5 cells with quercetin or an Hsf1 siRNA reduced p53 nuclear importation and inhibited p53-mediated activation of a p21 reporter. Most convincingly, p53 nuclear importation could be restored in ALTR12 cells by introducing an exogenous Hsf1 gene. Collectively, our result suggests that Hsf1 is required for p53 nuclear importation and activation and implies that heat shock factors play a role in the regulation of p53.

Cortactin (CTTN), first identified as a major substrate of the Src tyrosine kinase, actively participates in branching F-actin assembly and in cell motility and invasion. CTTN gene is amplified and its protein is overexpressed in several types of cancer. The phosphorylated form of cortactin (pTyr(421)) is required for cancer cell motility and invasion. In this study, we demonstrate that a majority of the tested primary colorectal tumor specimens show greatly enhanced expression of pTyr(421)-CTTN, but no change at the mRNA level as compared to healthy subjects, thus suggesting post-translational activation rather than gene amplification in these tumors. Curcumin (diferulolylmethane), a natural compound with promising chemopreventive and chemosensitizing effects, reduced the indirect association of cortactin with the plasma membrane protein fraction in colon adenocarcinoma cells as measured by surface biotinylation, mass spectrometry, and Western blotting. Curcumin significantly decreased the pTyr(421)-CTTN in HCT116 cells and SW480 cells, but was ineffective in HT-29 cells. Curcumin physically interacted with PTPN1 tyrosine phosphatases to increase its activity and lead to dephosphorylation of pTyr(421)-CTTN. PTPN1 inhibition eliminated the effects of curcumin on pTyr(421)-CTTN. Transduction with adenovirally-encoded CTTN increased migration of HCT116, SW480, and HT-29. Curcumin decreased migration of HCT116 and SW480 cells which highly express PTPN1, but not of HT-29 cells with significantly reduced endogenous expression of PTPN1. Curcumin significantly reduced the physical interaction of CTTN and pTyr(421)-CTTN with p120 catenin (CTNND1). Collectively, these data suggest that curcumin is an activator of PTPN1 and can reduce cell motility in colon cancer via dephosphorylation of pTyr(421)-CTTN which could be exploited for novel therapeutic approaches in colon cancer therapy based on tumor pTyr(421)-CTTN expression.

Teratoma of the orbit is rare; very few cases have been published in literature. A case of orbital teratoma in a neonate is presented where the proptosis was massive enough to obscure the eyeball. Clinically, the diagnosis of teratoma was considered. As there was no possibility of salvaging the eye, exenteration of the orbit was done. Orbital teratomas are generally benign. Histopathological examination revealed the features of malignant teratoma.

Gas Diffusion Layers (GDLs) of Proton Exchange Membrane Fuel Cells (PEMFCs) are usually subject to polytetrafluoroethylene (PTFE) treatment in a single stage. The impact of multistage PTFE treatment on the mechanical and electrochemical durability of GDLs used in PEMFCs, is reported here. With the same total amount of PTFE in the GDL, substrates treated with PTFE in multiple stages are seen to possess distinctly improved mechanical and electrochemical durability compared to GDLs treated with PTFE in a single stage. The difference in structure and hydrophobicity of the GDLs, when they are subjected to the two different PTFE treatment routes, are examined to understand the reasons for the improvements. The results indicate that there is a change in surface morphology, pore size distribution, and hydrophobicity of the GDL samples depending on the treatment route adopted. It is observed that it is possible to establish a gradient in PTFE profile in the GDL by adopting multistage treatment. Such gradients counteract loss in hydrophobicity resulting from compression cycles during cell assembly and carbon corrosion due to electrochemical aging. The results reveal that GDLs subject to multistage PTFE treatment, can have increased lifetime as opposed to conventional single stage PTFE treated GDL. � 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Inverse Marcus-Gunn phenomenon is very rare. It is usually acquired. We report a young male patient presenting with congenital ptosis and inverse Marcus-Gunn phenomenon.

Background 14-3-3 proteins are a family of highly conserved proteins that are involved in a wide range of cellular processes. Recent evidence indicates that some of these proteins have oncogenic activity and that they may promote tumorigenesis. We previously showed that one of the 14-3-3 family members, 14-3-3gamma, is over expressed in human lung cancers and that it can induce transformation of rodent cells in vitro. Methods qRTPCR and Western blot analysis were performed to examine 14-3-3gamma expression in non-small cell lung cancers (NSCLC). Gene copy number was analyzed by qPCR. P53 mutations were detected by direct sequencing and also by western blot. CHIP and yeast one hybrid assays were used to detect p53 binding to 14-3-3gamma promoter. Results Quantitative rtPCR results showed that the expression level of 14-3-3gamma was elevated in the majority of NSCLC that we examined which was also consistent with protein expression. Further analysis of the expression pattern of 14-3-3gamma in lung tumors showed a correlation with p53 mutations suggesting that p53 might suppress 14-3-3 gamma expression. Analysis of the gamma promoter sequence revealed the presence of a p53 consensus binding motif and in vitro assays demonstrated that wild-type p53 bound to this motif when activated by ionizing radiation. Deletion of the p53 binding motif eliminated p53's ability to suppress 14-3-3gamma expression. Conclusion Increased expression of 14-3-3gamma in lung cancer coincides with loss of functional p53. Hence, we propose that 14-3-3gamma's oncogenic activities cooperate with loss of p53 to promote lung tumorigenesis.

Gas diffusion layer (GDL) is a porous medium placed between the flow field and the catalyst layer in a proton exchange membrane fuel cell (PEMFC), and experiences electrochemical aging and mechanical stresses during usage. In the present work carbon cloth and carbon paper, two commonly used GDLs in PEMFC, are electrochemically aged in a simulated PEMFC environment. The results indicate that carbon paper is less prone to oxidation when compared to carbon cloth, which can be attributed to higher degree of graphitization of carbon fibers in the paper. However, carbon paper suffers greater loss of structural stability due to the adverse effects of aging on the fiber matrix interface. Increased weakening of paper when compared to cloth, after electrochemical aging, results in higher residual strain when subjected to cyclic compression and an increased intrusion of paper into the flow field channel when compared to cloth GDL. � 2011, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

Proton Exchange Membrane Fuel Cell (PEMFC) components are known to deteriorate during use, in time scales much shorter than that required for commercially successful deployment of this technology. Therefore, servicing operations such as identifying and replacing poorly performing components will likely be required to extend the operational lifetime of PEMFC stacks. During such servicing operations fuel cell components are subjected to cyclic compression and expansion due to opening and rebuilding of the fuel cell stack. This cyclic compression may further contribute to the deterioration of PEMFC components. There are several reports in the literature showing the effect of static compression on change in GDL properties, however the present work focuses on the effect of cyclic compression on GDL properties, an aspect that has not been reported in detail elsewhere. This paper focuses on the impact of cyclic compression on the Gas Diffusion Layer (GDL). The results indicate that cyclic compression causes significant and irreversible changes to the structure and properties of the GDL such as surface morphology, surface roughness, pore size, void fraction, thickness, electrical resistance, contact angle, water uptake and in-plane permeability. The implications of these results are considered. � 2009 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

Dietary modulation of cancer & cancer biomarkers Dietary item or component studied:ATRA (all-trans-retinol)Outcome studied (cancer or cancer biomarker):Cervical cancerSystem used (in vitro, animals, humans):humansStudy design (if human):case-controlStudy size (if human):20 controls, 20 low grade squamous intraepithelial lesions, 30 high grade squamous intraepithelial lesions, 60 invasive cancerTissue/biological material/sample size:10-15 sections of 10μm uterine, blood samplesMode of exposure (if in vivo):normal diet (not intervention)Impact on outcome (including dose-response):control ATRA level 0.6183+/-0.024LSIL ATRA level 0.5466+/-0.095, 9 people had HPV6, 11 had HPV11,HSIL ATRA level 0.4930+/-0.16, 6 had HPV6, 2 had HPV11,14 had HPV16, 8 had HPV18INVASIVE ATRA level 0.3097+/-0.077, 42 had HPV16, 18 had HPV18. KEYWORDS CLASSIFICATION: analysis;Adult;biomarkers of exposure & effect: field studies;biomarkers of exposure & effect: validation;biosynthesis;blood;Biotechnology;classification;complications;Cell Growth Processes;Cell Transformation,Viral;Cervical Intraepithelial Neoplasia;dietary modulation of cancer & cancer biomarkers;dietary modulation of carcinogenesis-related pathways;Female;genetics;Humans;India;Middle Aged;Neoplasm Staging;pathology;physiology;Papillomaviridae;Papillomavirus Infections;Polymerase Chain Reaction;Proliferating Cell Nuclear Antigen;Research;therapy;Tretinoin;Uterine Cervical Neoplasms;validation;virology;field studies. OBJECTIVE: In uterine cervical cancer, certain oncogenic HPV types are considered as key etiologic factor. But the progression of HPV associated cervical precancerous lesions depends on many other factors such as oncogenes, immune system, anti-viral factors etc. This study is therefore focused on the effect of an important dietary anti-viral factor called All Trans Retinoic Acid (ATRA) on the development of HPV associated cervical cancer as it is found higher in poor socioeconomic people. METHOD: We analyzed a total population of 130 including control subjects who have no complaints of uterine cervical lesions and the HPV-6/11, 16/18 infected cases of low grade squamous intraepithelial lesions [SIL], high grade squamous intraepithelial lesions [HSIL], and invasive cancers, for serum ATRA level. This study also focused to find out the association of serum ATRA level with the proliferation status in terms of proliferating cell nuclear antigen (PCNA) expression as it is an anti-proliferation agent and with the grades of cervical lesions, using SPSS statistical package. RESULTS: The results showed a highly significant negative association for serum ATRA level with different stages of cervical lesions (F = 3.305; P = 0.000) by one-way ANOVA and with intensity of PCNA expression (r = -0.825; P < 0.01) by Pearson's correlation test. A highly significant association was observed for the PCNA expression with the grades of cervical lesions too (F = 37.89; P = 0.000). Further, we found from our data that all the invasive cancer cases were infected with HPV-16/18 and none with HPV-6/11. Hence, we analyzed the association of serum ATRA level with HPV-16/18 infected preinvasive cases in developing invasiveness, by Fisher's Exact Test, using Graph Pad Prism as shown in Table 1. The results show an odds ratio (OR) of 36.93 and a relative risk (RR) of 4.99 with an 95% interval being 2.896 to 8.603, which is significant at the level of P = 0.0001 for the reduced [

Enteromorpha compressa a marine green algal species grows extensively in North coastal Andhra Pradesh. Besides its nutritional importance it has also been identified as source of anti-anaphylactic compound(s).E. compressa extracts alleviated the IgE levels raised against ovalbumin and other allergens in mice. Further,Enteromorpha extract also significantly down regulated the serum IgE levels in different murine models irrespective of their genetic background. The results obtained in this study suggest thatE. compressa extract has compound(s), which inhibit IgE immune response and may have potential in curing various types of allergies.

The influence of various mechanical, metallurgical, and environmental parameters on fatigue crack growth behaviour has been broadly explained elsewhere using the crack closure concept. In this paper the concept of a crack closure mechanism map is proposed in order to predict crack closure mechanisms operating under a given set of loading conditions for any alloy/microstructure. The domains of plasticity induced, roughness induced, and oxide induced crack closure mechanisms are mapped in Kmax–∆K space using various boundary equations. In Part 1 of this paper, the boundary equations are derivedfrom conditions related to the loading conditions.

Crack closure mechanism maps are constructed for a variety of ferrous and non-ferrous alloys using the boundary equations derived in Part 1. Extensive fatigue crack growth studies involving crack closure measurements and fractography were performed to validate the predictions of the crack closure mechanism maps developed in this way. It is demonstrated that the dominance of a particular mechanism under a given set of loading conditions is dependent on the deformation behaviour, controlling microstructure unit, yield strength, texture, and component thickness. Finally, some possible engineering applications of crack closure mechanism maps are suggested.

Many engineering components are subjected to multiaxial type of fatigue loading and the fatigue life relation based on uniaxial testing needs modifications before it could be used for multiaxial condition. In this paper a brief review of the different approaches based on stress and strain is presented for the correlation of bulk parameters with the fatigue life and the merits and limitations are discussed. ? 1995 the Indian Academy of Sciences.

The creep life of low-alloy steels has been analyzed based on the ?-envelope method. A parameter that compensates both the stress and the time axes is proposed involving the coefficients of the creep strain-time relations. ? 1992 ASM International.

Experimental investigations have been carried out to study the creep crack growth in types 316, 308 Cb, and 304 L stainless steel in the temperature range of 873–1073 K under plane stress condition. Testings have been carried out with both the base metal and the welded composite joints, because such joints are commonly used in nuclear power industries. Among the various parameters tried to correlate the creep crack growth, the energy rate line integral has been found to give the best description of the crack growth rate. The steady-state energy rate line integral has been found to correlate well with the rupture time. Based on this observation, life estimations are presented for thin components containing various initial defect sizes.

Creep curves of 0·5Cr–0·5Mo–0·25V steel have been analysed based on a simple power function of time. The long term creep properties, namely, the creep rate and the rupture lifetimes at low stress levels can be very well predicted by this simple power function. The Monkman–Grant relationship can also be obtained based on the predicted values.MST/1411

Copper films (210 – 1650 Å) were deposited onto glass microslides by vacuum evaporation. The films were subjected to heat treatment at a constant rate and the variation of electrical resistance with temperature was measured. The defect density and activation energy were calculated for different thicknesses from the knowledge of the change in electrical resistance with temperature and time. The defect density, F0 (E)max, varies from 17.2 to 6.05 μΩ•cm eV−1 in the thickness range 210 – 1650 Å whereas no appreciable variation in the activation energy is observed.Thickness dependence of resistivity and temperature coefficient of resistivity (TCR) were studied in the above thickness range and the bulk resistivity and TCR were found to be 1.75 μΩ•cm and 5.5 × 10−3 K−1 respectively. Assuming the scattering coefficient to be zero, the mean free path of conduction electrons was estimated. From the knowledge of the bulk resistivity and mean free path, the Fermi surface area and the effective free electron density per atom were evaluated as 21.86 × 1016 cm−2 and 0.92 respectively.