Boron carbide thin film surface characterization after graphitic carbon removal using low-pressure oxygen gas RF plasma.

B 4 C-coated thin film mirrors are used in high brilliance synchrotron and x-ray free electron laser beamlines due to their low absorption coefficient and high thermal stability. As in the case of gold, platinum, and other thin film mirrors, B 4 C-coated mirrors also are affected due to synchrotron radiation-induced carbon contaminations in beamlines. In the present study, a graphitic carbon (C) layer deposited on top of boron carbide (B x C) thin film surface is removed by five successive oxygen radio frequency (RF) plasma exposures (RF power, 10 W; O 2 flow, 30 sccm; exposure time, 10 min each). Before and after the carbon layer removal, structural and compositional properties of the B x C/C bilayer are characterized by soft x-ray reflectivity, x-ray photoelectron spectroscopy, grazing angle x-ray diffraction, and Raman spectroscopy techniques. Characterization results reveal that in the first four exposures the carbon layer thickness decreases continuously without affecting the B x C layer properties; however, in the fifth exposure, the carbon layer is completely removed along with a partial etching of the B x C layer too.

Economic feasibility study of aerators in aquaculture using life cycle costing (LCC) approach.

Selection of aerator is a very important aspect in aquaculture operations. The selected aerator must be economically efficient and should be able to fulfil the requirement of oxygen supply in the pond water. In the present study, economic feasibility of nine different types of aerators, namely, perforated pooled circular stepped cascade (PPCSC), pooled circular stepped cascade (PCSC), circular stepped cascade (CSC), paddle wheel (PWA), spiral aerator (SA), propeller-aspirator-pump (PAA), submersible (SUBA), impeller aerator (IA) and air-jet aerator (AJA) was assessed based on capitalization method, a life cycle costing (LCC) approach. The results revealed that the PPCSC aerator can be considered as the most suitable aerator when dissolved oxygen (DO) content in the pond water is less than equal to 3 mg/L, and pond water volume (V) is less than 2100 m3. In other situations, mostly when pond water volume is more, IA proves to be the most suitable aerator, followed by PWA, PPCSC, and other available aerators. The sensitivity analysis conducted by using varying stocking density and capital cost also showed the same trend with regard to selection of aerators. This life cycle costing approach for selection of aerator can be implemented for any types of cultured species at any prevailing environmental conditions.

Active microrheology using pulsed optical tweezers to probe viscoelasticity of lamin A.

Lamins are nucleoskeletal proteins of mammalian cells that stabilize the structure and maintain the rigidity of the nucleus. These type V intermediate filament proteins which are predominantly of A and B types provide necessary tensile strength to the nucleus. Single amino acid missense mutations occurring all over the lamin A protein form a cluster of human diseases termed as laminopathies, most of which principally affect the muscle and cardiac tissues responsible for load bearing functionalities of the body. One such mutation is A350P which causes dilated cardiomyopathy in patients. It is postulated that a change from alanine to proline in the α-helical coiled-coil forming 2B rod domain of the protein might severely disrupt the propensity of the filaments to polymerise into functional higher order structures required to form a fully functional lamina with its characteristic elasticity. In this study, we have elucidated for the very first time, the application of active microrheology employing oscillating optical tweezers to investigate any alterations in the viscoelastic parameters of the mutant protein meshwork in vitro, which might translate into possible changes in nuclear plasticity. We confirmed our findings from this robust yet fast method by imaging both the wild type and mutant lamin A networks using a super resolution microscope, and observed changes in the mesh size which corroborate our measured changes in the viscoelastic parameters of the lamins. This method could thus be extended to conduct microrheological measurements on any intermediate filament protein thus bearing significant implications in laminopathies and other diseases associated with intermediate filaments.

Effect of oxygen partial pressure in deposition ambient on the properties of RF magnetron sputter deposited Gd2O3 thin films.

Gadolinium oxide is an excellent optical material that offers high transmission in a wide wavelength range of 200-1600 nm and exhibits a high bulk refractive index of ∼1.80 at 550 nm. In the present study, a set of Gd2O3 thin films has been deposited on fused silica substrates by RF sputtering of a Gd2O3 target under various O2 to Ar flow ratios. The samples have been characterized by grazing incidence x-ray diffraction (GIXRD) to study the long range structural behavior, by GIXR to study density and surface roughness of the films, by atomic force microscopy measurements to study morphological properties, by Rutherford backscattering measurements for compositional studies, and by transmission spectrophotometry and spectroscopic ellipsometry techniques to study their optical properties. It has been observed that the films deposited with 10% oxygen partial pressure have low density, high surface roughness, and high void content, which results in a low value of refractive index of this film, and film quality improves as oxygen partial pressure is further increased. Extended x-ray absorption fine structure measurement with synchrotron radiation has also been employed to extract local structural information around Gd sites, which has in turn been used to explain some of the observed macroscopic properties of the films.

Study of the microstructure information of GaAs epilayers grown on silicon substrate using synchrotron radiation.

Williamson-Hall (WH) analysis is a well established method for studying the microstructural properties of epilayers grown on foreign substrates. However, the method becomes inapplicable in specific cases where the structure factor considerations and the presence of anti-phase domains forbid the data acquisition for certain reflections in conventional high-resolution X-ray diffraction (HRXRD) measurements. Here, this limitation is overcome by exploiting the large intensity (25 µW mm(-2)) and high photon energy (15.5 keV) of the X-ray beam obtained from a synchrotron radiation source. The lateral coherence length, vertical coherence length, tilt and micro-strain of GaAs epilayers grown on Si substrate have been successfully measured using the conventional WH analysis. The microstructure information obtained from the conventional WH analysis based on the data acquired at the synchrotron radiation source is in reasonable agreement with the results obtained from atomic force microscope and surface profiler measurements. Such information cannot be obtained on a laboratory-based HRXRD system where modification of the WH method by involving a set of parallel asymmetric crystallographic planes is found to be essential. However, the information obtained from the modified WH method is along a different crystallographic orientation.

A novel mannoside-glycocluster adjuvant: Compared in vitro to CpG ODN and MPL and tested in vivo in mouse asthma model.

BACKGROUND: Allergen-specific immunotherapy balances the Th2-biased immunity towards Th1 and Treg responses. Adjuvants are used in allergen preparations to intensify the immune responses. The increased prevalence of allergies in developed societies has been associated with decreased microbial load during childhood. This has initiated a search for microbial structures to be used as adjuvants. Our study has shown that a synthetic triacedimannose (TADM) may suppress the Th2-type allergic inflammatory response. The aim of this study was to compare the properties of TADM with capacities of other adjuvants, CpG ODN and MPL, to modulate cytokine production in PBMC and regulate sensitisation in an OVA-sensitised mouse asthma model. METHODS: The effects of TADM were studied in vitro on birch stimulated PBMC cultures of birch allergic rhinitis patients with other known adjuvants. Cytokines in supernatants were measured by Luminex. Effects of TADM were analysed in vivo in a mouse model of OVA-induced allergic asthma by analysing BAL, cytokine mRNA and serum antibodies. RESULTS: TADM was the only adjuvant that significantly suppressed the production of all birch induced Th2-type cytokines. In a murine model, TADM significantly suppressed the specific IgE production and enhanced IFN-γ production. CONCLUSIONS: TADM suppresses the birch allergen induced Th2-type cytokine responses in allergic subjects more efficiently than the two other adjuvants, MPL and CpG ODN. TADM is immunomodulatory also in vivo and decreases the IgE levels and increases the IFN-γ responses in a murine model. These results suggest that TADM may be a promising candidate for novel adjuvants in immunotherapy.

Assessment of water quality using multivariate statistical techniques in the coastal region of Visakhapatnam, India.

The present study was intended to develop a Water Quality Index (WQI) for the coastal water of Visakhapatnam, India from multiple measured water quality parameters using different multivariate statistical techniques. Cluster analysis was used to classify the data set into three major groups based on similar water quality characteristics. Discriminant analysis was used to generate a discriminant function for developing a WQI. Discriminant analysis gave the best result for analyzing the seasonal variation of water quality. It helped in data reduction and found the most discriminant parameters responsible for seasonal variation of water quality. Coastal water was classified into good, average, and poor quality considering WQI and the nutrient load. The predictive capacity of WQI was proved with random samples taken from coastal areas. High concentration of ammonia in surface water during winter was attributed to nitrogen fixation by the phytoplankton bloom which resulted due to East India Coastal Current. This study brings out the fact that water quality in the coastal region not only depends on the discharge from different pollution sources but also on the presence of different current patterns. It also illustrates the usefulness of WQI for analyzing the complex nutrient data for assessing the coastal water and identifying different pollution sources, considering reasons for seasonal variation of water quality.

[Real-time 3 dimensional full volume data set : benefits in problem focused intraoperative transesophageal echocardiography]. / "Real-time-3-dimensional-full-volume"-datensatz : nutzen in der problemfokussierten intraoperativen transösophagealen echokardiographie.

BACKGROUND: Comprehensive intraoperative transesophageal echcardiography (TEE) includes various measurements for quantification of cardiac chambers and valves based on multiple two dimensional (2D) standard views. Due to shortness of time during cardiac surgery most centres in Germany only carry out problem focussed intraoperative examinations which does not allow the complete repertoire of measurements to be exhausted. The aim of this study was to investigate which measurements for cardiac chamber and valve quantification can be performed with the acquisition of a real-time 3D full volume (RT-3D-FV) data set and to compare these measurements with those based on standard 2D views. MATERIALS AND METHODS: In patients undergoing elective surgical mitral valve repair a comprehensive 2D TEE examination according to the guidelines of the American Society of Echocardiography (ASE) and the Society of Cardiovascular Anesthesiologists (SCA) was performed after induction of anesthesia. Additionally, a RT-3D-FV TEE data set based on the midesophageal four chamber view was recorded (iE 33, Philips, Netherlands). All measurements of the 2D TEE and the RT-3D-FV dataset (Qlab) were performed offline by two independent examiners. RESULTS: After approval by the local ethic committee and obtaining written informed consent 50 patients (31 male and 19 female) with a mean age of 59.4 ± 11.5 years were enrolled in this study. All measurements recommended for chamber and valve quantification could be performed on the basis of the RT-3D-FV data set except for measurements of the sinus of Valsalva and the sinotubular junction. There was good correlation between the results of the two methods. CONCLUSIONS: For intraoperative problem focussed TEE examinations the acquisition of an additional RT-3D-FV TEE data set allows accurate measurement of most of the recommended chamber and valve quantification parameters.

Prediction of the annuloplasty ring size in patients undergoing mitral valve repair using real-time three-dimensional transoesophageal echocardiography.

AIMS: We sought to investigate the additional value of real-time three-dimensional transoesophageal echocardiography (RT 3D TOE)-guided sizing for predicting annuloplasty ring size during mitral valve repair. METHODS AND RESULTS: In 53 patients undergoing elective mitral valve repair, an RT 3D TOE was performed pre- and post-operatively. The digitally stored loops were imported into a software for mitral valve assessment. The annuloplasty ring size was predicted by superimposing computer-aided design (CAD) models of annuloplasty rings onto Live 3D zoom loops, measurement of the intercommissural distance, or the height of the anterior mitral leaflet. The surgeon implanted the annuloplasty ring according to the usual surgical technique and was blinded to the echocardiographic measurement results. Pre-operative correlation between the selected ring size with mitral valve assessment and the actual implanted annuloplasty ring size was 0.91. The correlation for measurement of the intercommissural distance was 0.55 and for measurement of the height of the anterior mitral leaflet 0.75. The post-operative correlation with the actual implanted ring size was 0.96 for mitral valve assessment, 0.92 for intercommissural distance, and 0.79 for the anterior mitral leaflet height. CONCLUSION: Superimposition of annuloplasty ring CAD models on the Live 3D zoom loops of the mitral valve using mitral valve assessment is superior to two-dimensional measurements of the intercommissural distance or the height of the anterior mitral leaflet in predicting correct annuloplasty ring size.

Utilisation of waste medicine wrappers as an efficient low-cost electrode material for microbial fuel cell.

Waste generation from healthcare facilities now has become a concerning issue as it contain plastic and metals. Medicine wrappers are one of the major portions of healthcare solid waste, which impel intensive solid waste management practice due to fewer possibilities of deriving by-products. However, it can be recycled and used as an electrode material in microbial fuel cells (MFCs). An electrode material for application in MFCs is a crucial component, which governs total fabrication cost as well as power recovery, thus a cost-effective, stable and durable electrode is essential. In this endeavour, a new metallic (aluminium) waste material, a waste medicine wrapper (WMW), was evaluated for feasibility to be used as anode/cathode in MFCs. Based on the stability test under corrosive environment (1 N KCl), the WMW electrode sustained a maximum current of 46 mA during cyclic voltammetry (CV) and noted only 14% reduction in current at an applied voltage of +0.4 V after 2500 s in chronoamperometry, indicating its good stability. Power recovery from MFC using WMW was higher than the MFC using bare carbon felt as an anode (27 vs. 21 mW/m2). The entire analytical test results viz. CV, electrochemical impedance spectroscopy and power performance established WMW as an excellent anode rather than cathode material.

Structural, optical and electronic properties of Ni1-x Co x O in the complete composition range.

Crystallographic and electronic structures of phase pure ternary solid solutions of Ni1-x Co x O (x = 0 to 1) have been studied using XRD, EXAFS and XAS measurements. The lattice parameter of the cubic rock-salt (RS) Ni1-x Co x O solid solutions increases linearly with increasing Co content and follows Vegard's law, in the complete composition range. A linear increase in the bond lengths (Ni/Co-O, Ni-Ni and Ni-Co) with "x", closely following the bond lengths determined from virtual crystal approximation (VCA), is observed, which implies that there is only a minimal local distortion of the lattice in the mixed crystal. The optical gap of the ternary solid solution determined from diffuse reflectivity measurements shows neither a linear variation with Co composition nor bowing, as observed in many ternary semiconductors. This trend in the variation of optical gaps is explained by probing the conduction band using XAS at the O K-edge. We have observed that the variation in the onset energy of the conduction band edge with "x" is very similar to the variation in the optical gap with "x", thus clearly indicating the dominant role played by the conduction band position in determining the optical gap. The variation in the intensities of the pre-edge peak in the XANES spectra measured at Ni and Co K-edges, and the L1/2 peak in XAS spectra measured at Ni and Co L-edges, is found to depend on the unoccupied O 2p-metal-(Ni/Co) 3d hybridized states and the bond lengths.

Biofouling effects on the performance of microbial fuel cells and recent advances in biotechnological and chemical strategies for mitigation.

The occurrence of biofouling in MFC can cause severe problems such as hindering proton transfer and increasing the ohmic and charge transfer resistance of cathodes, which results in a rapid decline in performance of MFC. This is one of the main reasons why scaling-up of MFCs has not yet been successfully accomplished. The present review article is a wide-ranging attempt to provide insights to the biofouling mechanisms on surfaces of MFC, mainly on proton exchange membranes and cathodes, and their effects on performance of MFC based on theoretical and practical evidence. Various biofouling mitigation techniques for membranes are discussed, including preparation of antifouling composite membranes, modification of the physical and chemical properties of existing membranes, and coating with antifouling agents. For cathodes of MFC, use of Ag nanoparticles, Ag-based composite nanoparticles, and antifouling chemicals is outlined in considerable detail. Finally, prospective techniques for mitigation of biofouling are discussed, which have not been given much previous attention in the field of MFC research. This article will help to enhance understanding of the severity of biofouling issues in MFCs and provides up-to-date solutions. It will be beneficial for scientific communities for further strengthening MFC research and will also help in progressing this cutting-edge technology to scale-up, using the most efficient methods as described here.

Cognitive dysfunction in an urban Indian population--some observations.

There is no prospective study of mild cognitive impairment (MCI) in India. This study aims to determine the prevalence rate of dementia and to prospectively analyze a group of patients with MCI. A door-to-door cross-sectional cluster survey was conducted in Kolkata, India, among those aged >50 years to estimate the prevalence rate of dementia. Then annual assessment of cognitive function using a validated questionnaire battery was undertaken among 21 elderly individuals with memory complaints for 4 consecutive years. A total of 53,907 persons were surveyed. The crude prevalence rates of dementia were 0.62% (95% CI 0.44-0.84) and 1.25% (95% CI 0.87-1.74) among those >50 and >60 years of age, respectively. The weighted prevalence rate among those above 50 years was 0.95% (95% CI 0.68-1.29). Alzheimer's disease was the commonest subtype (55%) followed by vascular dementia (36%). In a prospective study, MCI remained static, converted to dementia or reverted to normalcy. There was also transition from one subtype of MCI to another. A similar outcome of MCI is also noted in Western nations. However, the prevalence rate of dementia in Eastern India remained quite low.

Growth of textured nanocrystalline cobalt ferrite thin films by pulsed laser deposition.

Cobalt ferrite thin films have been deposited on fused quartz substrates by pulsed laser deposition at various substrate temperatures, T(s) (25 degrees C, 300 degrees C, 550 degrees C and 750 degrees C). Single phase, nanocrystalline, spinel cobalt ferrite formation is confirmed by X-ray diffraction (XRD) for T(s) > or = 300 degrees C. Conventional XRD studies reveal strong (111) texturing in the as deposited films with T(s) > or = 550 degrees C. Bulk texture measurements using X-ray orientation distribution function confirmed (111) preferred orientation in the films with T(s) > or = 550 degrees C. Grain size (13-16 nm for T(s) > or = 300 degrees C) estimation using grazing incidence X-ray line broadening analysis shows insignificant grain growth with increasing T(s), which is in good agreement with grain size data obtained from transmission electron microscopy.

Prevalence of major neurological disorders among geriatric population in the metropolitan city of Kolkata.

Well-conducted neuroepidemiological studies for the geriatric population are rare in India. In view of the growing aging population, we planned to determine the prevalence of common neurological disorders among the elderly population in the city of Kolkata. This was a cross-sectional study of a stratified random sample of the city population and carried in two stages through house to house survey. Initially, trained non-medical workers screened the cases with a validated family questionnaire and then a neurologist examined all the screened positive cases. A validated neuropsychological screening test was also applied among the elderly population with cognitive complaints. Results showed prevalence rates (per 1000 elderly population--> or = 60 years) of following disorders in decreasing order: stroke--33.93, essential tremor--13.76, dementia--7.89, Parkinsonism--3.30 and epilepsy--2.57. Sex-specific prevalence showed that stroke was commoner among men and that of other disorders among women. Age-specific prevalence recorded progressive increase in the rates of all disorders among both genders, though not uniformly among women. Overall the crude prevalence of neurological disorders was 60.9 per 1000. The present study shows higher rate of stroke as compared to other neurological disorders among elderly population in India, which needs urgent attention.

Investigation of Dual-Ion Beam Sputter-Instigated Plasmon Generation in TCOs: A Case Study of GZO.

The use of the high free-electron concentration in heavily doped semiconductor enables the realization of plasmons. We report a novel approach to generate plasmons in Ga:ZnO (GZO) thin films in the wide spectral range of ∼1.87-10.04 eV. In the grown GZO thin films, dual-ion beam sputtering (DIBS) instigated plasmon is observed because of the formation of different metallic nanoclusters are reported. Moreover, formation of the nanoclusters and generation of plasmons are verified by field emission scanning electron microscope, electron energy loss spectra obtained by ultraviolet photoelectron spectroscopy, and spectroscopic ellipsometry analysis. Moreover, the calculation of valence bulk, valence surface, and particle plasmon resonance energies are performed, and indexing of each plasmon peaks with corresponding plasmon energy peak of the different nanoclusters is carried out. Further, the use of DIBS-instigated plasmon-enhanced GZO can be a novel mean to improve the performance of photovoltaic, photodetector, and sensing devices.

Structure and content of the Entamoeba histolytica genome.

The intestinal parasite Entamoeba histolytica is one of the first protists for which a draft genome sequence has been published. Although the genome is still incomplete, it is unlikely that many genes are missing from the list of those already identified. In this chapter we summarise the features of the genome as they are currently understood and provide previously unpublished analyses of many of the genes.

A random sample survey for prevalence of major neurological disorders in Kolkata.

BACKGROUND & OBJECTIVES: Large scale epidemiological studies on neurological disorders are very few in India. We therefore planned to conduct a cross-sectional population-based epidemiological study on a stratified randomly selected sample from the city of Kolkata to study the prevalence of major neurological disorders such as epilepsy, stroke, dementia and Parkinsonism. METHODS: The method of case ascertainment was two- stage house-to-house survey; the first stage was undertaken by a field team consisting of four field workers and a neuropsychologist. Screening questionnaire based on National Institute of Mental Health and Neuro Sciences (NIMHANS) protocol was used. In the second stage a neurologist examined all the screened positive cases. RESULTS: A total of 52,377 subjects participated in the study. The crude prevalence rates (per 100,000 population) of major neurological disorders with 95 per cent confidence intervals (95% CI) and age adjusted rates (AAR) based on US 2000 population were 557.5 (95% CI 496.17-624.40 and AAR - 516.77) in epilepsy, 486.85 (95% CI 377.0 to 551.11 and AAR-765.68) in stroke, 87.82 (95% CI 64.02-117.50 and AAR-168.4) in dementia and 45.82 (95% CI 29.64-67.63 and AAR-71.64) in Parkinsonism. The weighted prevalence rates (per 100,000) of the whole population based on re-screening of 10 per cent of negative samples were 763.89 (95% CI 690.55- 842.57) in epilepsy, 624.32 (95% CI 555.64-699.24) in stroke and 139.37 (95% CI 108.71-176.06) in dementia. INTERPRETATION & CONCLUSION: A high rate of stroke and overall lower prevalence of Parkinsonism and dementia was recorded as compared to western studies. High prevalence rate of stroke emphasizes the need to study incidence, morbidity and mortality profile of stroke including its socio-economic impact and also case-control analysis to determine the underlying risk factors.

Biofouling inhibition and enhancing performance of microbial fuel cell using silver nano-particles as fungicide and cathode catalyst.

Morphological analysis of biofouling developed on cathode surface in an air-cathode microbial fuel cell (MFC) was performed. For sustaining power production and enhancing Coulombic efficiency (CE) of MFC, studies were conducted to inhibit cathode biofouling using different loadings of silver nanoparticles (Ag-NPs) with 5% and 10% Ag in carbon black powder. In MFC without using Ag-NPs in cathode (MFC-C), cathode biofouling increased the charge transfer resistance (Rct) from 1710Ω.cm(2) to 2409Ω.cm(2), and reduced CE by 32%; whereas in MFC with 10% Ag in cathode Rct increased by only 5%. Power density of 7.9±0.5W/m(3) in MFC using 5% Ag and 9.8±0.3W/m(3) in MFC using 10% Ag in cathode was 4.6 and 5.7-folds higher than MFC-C. These results suggest that the Ag-NPs effectively inhibit the fungal biofouling on cathode surface of MFCs and enhanced the power recovery and CE by improving cathode kinetics.

Eyelid-parotid metastasis: do we screen for coexisting masses? A case series.

OBJECTIVE: To report three cases illustrating that it is not unusual for a primary eyelid tumour to metastasise to the parotid gland and vice versa. CASE REPORTS: Two patients with malignant parotid tumours underwent radical parotidectomy and presented subsequently with eyelid lesions. Biopsy showed that both eyelid lesions were histologically similar to the primary parotid tumour. A third patient was noted to have ipsilateral upper eyelid and parotid gland tumours. Histology and immunocytochemistry were used to differentiate the primary tumour and the metastasis. CONCLUSION: These cases illustrate that tumours involving eyelids and parotid glands can present simultaneously or sequentially, and either of these structures could be the focus of primary or metastatic tumour. The important message for oculoplastic and parotid surgeons is to routinely assess both the periocular and parotid area when patients present with a mass in either structure.