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An indirect way of assessing cadmium concentration in confined volume was attempted. This aim was met by measuring the oxygen concentration before and after reaction with cadmium vapour. The deduced cadmium concentration value corroborated with the data obtained from cadmium vapour pressure at different temperature. [ABSTRACT FROM AUTHOR]

Organic Electrochemical Transistor fabricated from conducting polymer material, PEDOT: PSS has been demonstrated towards study of plant response to salt stress. Electrochemical impedance spectroscopic studies of OECT under both in‐vivo and in‐vitro salt stress monitoring conditions have been carried out. Change in ionic concentration induced in the biological system of a living plant subjected to salt stress has been elucidated in terms of change in impedance of biosensor integrated in its stem. The impedance data recorded was used to derive equivalent distributed‐element circuit models for the device, under both in‐vivo and in‐vitro conditions. [ABSTRACT FROM AUTHOR]

Electrochemical sensors were constructed using sodium-β-Al2O3 solid electrolyte and tested for sensing sodium aerosols. Performance of them was evaluated both in the laboratory and in plant environment. The sensors responded instantaneously to sodium aerosol and the typical response and retrace times were 5 min and 90 min respectively. [ABSTRACT FROM AUTHOR]

Metal oxides possess exceptional potential as base materials in emerging technologies. In recent times, significant amount of research works is carried out on these materials to assess new areas of applications, including optical, electronic, optoelectronic and biological domains. In such applications, the response and performance of the devices depend crucially, among other factors, on the size, shape and surface of the active oxide materials. For instance, the electronic and optical properties of oxides depend strongly on the spatial dimensions and composition [1]. The large number of atoms on the surface, and the effective van der Waals, Coulombic and interatomic coupling significantly modify the physical and chemical properties of the low dimensional oxide materials vis-á-vis its bulk counterparts. As a result, low dimensional oxide materials, such as nanoparticles, nanospheres, nanorods, nanowires, nanoribbon/nanobelts, nanotubes, nanodisks, nanosheets evoke vast and diverse interests. Thermal and physical deposition, hydro/solvothermal process, spray-pyrolysis, assisted self-assembly, oil-in-water microemulsion and template-assisted synthesis are regularly employed to synthesis one-, two- and three-dimensional nanostructures, which have become the focus of intensive research in mesoscopic physics and nanoscale devices. It not only provides good scopes to study the optical, electrical and thermal properties in quantum-confinement, but also offers important insights for understanding the functional units in fabricating electronic, optoelectronic, and magnetic devices of nanoscale dimension. Tin oxide (SnO2) is one such very important n-type oxide and wide band gap (3.6eV) semiconductor. Its good quality electrical, optical, and electrochemical properties are exploited in solar cells, as catalytic support materials, as solid-state chemical sensors and as high-capacity lithium-storage. Previously, Chopra et al. [2] reviewed different aspects of transparent conducting SnO2 thin films. Wang et al. [3] discussed device applications of nanowires and nanobelts of semiconductor oxides, including SnO2. Batzill et al. [4] discussed about the surface of single crystalline bulk SnO2. However, it is understood that neither there is any comprehensive review on various crystallographic phases, polymorphs, bulk modulus, lattice parameters and electronic states of SnO2, nor there is any updated compilation on the recent progress and scope on SnO2 nanostructures. Therefore, the proposed review covers the past and recent progress on the said topics and is summarized in the following manner. The available theoretical and experimental works on crystal structures, bulk modulus, lattice parameters are reviewed in details. The electronic states and the band structures of these phases are discussed next. Active crystal surfaces of SnO2 play vital roles in its many interesting properties, including sensing and catalytic applications. So, a short review is written on its different surfaces, its electronic structures and density of states. The discussion on the importance of morphological variations on the properties of SnO2 is followed by a review on different methods for obtaining such structures. A detail survey on the existing literature on techniques and mechanisms for the growth of nanostructures are included. SnO2 is efficiently employed in gas sensing applications. A review on such applications is compiled based on the role of morphology and performance. The future course of SnO2 as an important material in the contemporary research is also discussed. [ABSTRACT FROM AUTHOR]

The article discusses the life and work of Indian space scientist Udupi Ramachandra Rao, who was born in Karnataka, India in March 1932. Topics discussed include post graduation in physics from the Banaras Hindu University, study on cosmic ray particles using simulation of geomagnetic field at the Massachusetts Institute of Technology in Cambridge, Massachusetts and role of Rao in building first Indian satellite.

A single longitudinal mode micro-electro-mechanical system-tunable vertical cavity surface-emitting laser (VCSEL) was used to measure H $$_{2}$$O and HF absorption spectra in the 1,321-1,354 nm range at 55 kHz repetition rate ( $$\sim $$740 MHz/ns tuning rate). Pulse delay referencing was used to achieve an absorbance noise level of 0.004 (RMS), within a factor of 2.6 of the shot noise limit. The measured linewidths approach the low-pressure feature linewidths ( $$\sim$$790 MHz) characteristic of the gases studied, highlighting the single-mode nature of the VCSEL throughout each rapid wavelength sweep. At even higher tuning rates, molecular features became asymmetric and broad, consistent with rapid passage and Fourier effects. [ABSTRACT FROM AUTHOR]

Abstract: Traditionally, a visual servo control problem is formulated in the teach by showing framework with an objective to regulate a camera based on a reference (or desired) image obtained by a priori positioning the same camera at the desired task-space location. A new strategy is essential for a variety of applications where it may not be possible to position the camera a priori at the desired position/orientation. In this paper, a visual servo control approach, called “teach by zooming”, is formulated where the objective is to position/orient a camera based on a reference image obtained by another camera. For example, a fixed camera providing a wide area view of the scene can zoom in on an object and record a desired image for another camera. A non-linear Lyapunov-based controller is designed to regulate the image features acquired by an on-board camera to the corresponding image feature coordinates in the desired image acquired by the fixed camera in the presence of uncertain camera calibration parameters. The proposed control formulation becomes identical to the well-known teach by showing controller when the camera-in-hand can be located a priori to the desired position/orientation; thus enabling control in a wide range of applications. Experimental results for regulation control of a 7 degrees-of-freedom robotic manipulator are provided to demonstrate the performance of the proposed visual servo controller. [Copyright &y& Elsevier]

Abstract: India has established a ‘critical mass’ in terms of EO infrastructure for disaster management. Starting from IRS 1A in 1980s to the most recent CARTOSAT-2, India''s EO series of satellites are moving away from the generic to thematic constellations. The series of RESOURCESAT, CARTOSAT, OCEANSAT and forthcoming Radar Imaging Satellite (RISAT) satellites exemplifies the thematic characters of the EO missions. These thematic constellations, characterized with multi-platform, multi-resolution and multi-parameter EO missions, are important assets for disaster reduction. In the more specific term, these constellations in conjunction with contemporary EO missions address the critical observational gaps in terms of capturing the catastrophic events, phenomena or their attributes on real/near real time basis with appropriate spatial and temporal attributes. Using conjunctively the data primarily emanating these thematic constellations and all weather radar data from aerial platform and also from RADARSAT as gap-fillers has been a part of India''s EO strategy for disaster management. The infrastructure has been addressing the observational needs in disaster management. The high resolution imaging better than one-meter spatial resolution and also Digital Elevation Models (DEM) emanating from Cartosat series are providing valuable inputs to characterize geo-physical terrain vulnerability. Radar Imaging Satellite, with all weather capability missions, is being configured for disaster management. At present, the current Indian EO satellites cover the whole world every 40h (with different resolutions and swaths), and the efforts are towards making it better than 24h. The efforts are on to configure RESOURCESAT 3 with wider swath of 740km with 23m spatial resolution and also to have AWiFS type of capability at geo-platform to improve the observational frequencies for disaster monitoring. India''s EO infrastructure has responded comprehensively to all the natural disasters the country has faced in the recent times. As a member of International Charter on Space and Major Disasters, India has also been instrumental in promoting the related UN initiatives viz., RESAP of UN ESCAP, SPIDER of UN OOSA, Sentinel Asia of JAXA initiative and also of GEOSS initiative. The paper intends to illustrate India''s EO strategy for disaster reduction. [Copyright &y& Elsevier]

Abstract: Various alkali and alkaline earths hydroxides are reacted with hydrated alumina gel Al2O3·nH2O (80< n <120) in hydrophilic organic solvents to yield precursor(s) with metal cation entrapped in the matrix, with the general formula M y AlO y (OH)3−y (where M=Li, Na, K, Rb, Ca and Eu). Depending on the cation, the precursor crystallizes as metal-inserted gibbsite or boehmite structure. The nature of the precursor depends on the size of the cation, and its concentration, solvent used, solvent/water ratio, etc. These precursors yield M-β/β″-alumina phase on calcination at elevated temperatures in the case of sodium, potassium and rubidium. In the case of lithium, LiAl5O8 (spinel) phase is obtained. While calcium and europium give rise to calcium hexaaluminate and EuAlO3 (perovskite), respectively, on calcination. The need of metal ion-inserted-γ-alumina phase is emphasized in obtaining M-β/β″-alumina phase. [Copyright &y& Elsevier]

Abstract: India is looking for rejuvenating its sagging agricultural production and productivity by integrating high technology space inputs for both irrigated and rainfed areas. The Earth Observations (EO) products today serve as major inputs to policy, planning and targeted interventions, contributing to building social capitals, natural resources assets and environmental gains on the long-term basis. The benefits are mostly indirect and often difficult to quantify in terms of money. The cost benefit analysis of EO products is therefore an involved exercise and not many examples exist globally. The present paper, taking into account major national as well as some local level agriprojects in India, highlights the criticality of EO products in terms of their short-term as well as long-term economic and social values. Three aspects viz., catalytic, timeliness and enabling have been analyzed to visualize the role of EO products in a holistic fashion. In the catalytic role, EO inputs have been found to play a role in the successful implementation of major natural resources development projects. The cost of EO inputs may be of less than 2–5% to the total cost of the development projects, but the nature of such inputs are critical and catalytic. For example, a major project on reclamation of around 0.6 Mha sodic soils in Indo-Gangetic Plans costs US$89 million where EO products costs less than 2%; but demonstrates their catalytic roles in terms of identification, monitoring and evaluation and as inputs to mid-course corrections. The second aspect is timeliness in terms of opportunity cost. In India, Forecasting Agricultural Output Using Space-borne, Agro-meteorological and Land Observations (FASAL) project is carried out for in-season multiple crop production forecasting in support of strategic decision on trade, price and procurements. In the past, timely forecasts from FASAL have been found to be accurate and helpful for the country to plan many of its activities, including taking early decisions on wheat import to meet the shortfalls. The enabling role EO products have been demonstrated in several projects especially those related to building physical and social infrastructure and also natural resources assets building. The cost effective role EO has played in the watershed development planning and implementation in India, including improving the livelihoods as well as natural resources assets building, is one success story worth emulating in many developing countries. The most important aspect, however, is how the information is put to use for decision making and actual ground level implementation. The paper attempts to provide a glimpse of these aspects in a coherent fashion. [Copyright &y& Elsevier]

BACKGROUND: Male reproductive function has recently attracted increasing attention due to reports on time-related decline in semen quality. Furthermore, regional differences in the semen quality have also been reported. AIM: To investigate the semen quality among large cohort of infertile individuals at a regional level, in terms of the sperm concentration, total sperm motility, sperm morphology and incidence of azoospermia over a period of 13 years. SETTING: University infertility clinic at Kasturba Hospital, Manipal which is a tertiary healthcare centre serving the general population. DESIGN: Retrospective analysis. MATERIALS AND METHODS: This includes a total of 7770 subjects who presented for semen analysis from 1993 to 2005. The data regarding ejaculate volume, sperm density, motility, morphology and the incidence of azoospermia were collected. STATISTICAL ANALYSIS USED: One way analysis of variance (ANOVA), regression analysis and Chi square analysis. RESULTS: The average sperm density among infertile men during 2004-2005 was 26.61 ± 0.71 millions/mL which was significantly lower than the average sperm density observed in 1993- 1994 (38.18 ± 1.46 millions/mL). Similar trend was also observed for sperm motility (47.14% motile sperms vs. 61.16%) and normal sperm morphology (19.75% vs. 40.51%). Interestingly, the incidence of severe oligospermia (mean sperm density <10 millions/mL) observed in 2002-2005 and 1993-1997 demonstrated a significant inverse relationship (P < 0.001). CONCLUSION: Our study provides the first evidence that the quality of human semen evaluated for infertility is deteriorating in the southern part of the India over the years, probably due to environmental, nutritional, life style or socioeconomic causes. [ABSTRACT FROM AUTHOR]

Remote Sensing (RS) refers to the science of identification of earth surface features and estimation of their geo-biophysical properties using electromagnetic radiation as a medium of interaction. Spectral, spatial, temporal and polarization signatures are major characteristics of the sensor/target, which facilitate target discrimination. Earth surface data as seen by the sensors in different wavelengths (reflected, scattered and/or emitted) is radiometrically and geometrically corrected before extraction of spectral information. RS data, with its ability for a synoptic view, repetitive coverage with calibrated sensors to detect changes, observations at different resolutions, provides a better alternative for natural resources management as compared to traditional methods. Indian Earth Observation (EO) programme has been applications-driven and national development has been its prime motivation. From Bhaskara to Cartosat, India's EO capability has increased manifold. Improvements are not only in spatial, spectral, temporal and radiometric resolutions, but also in their coverage and value-added products. Some of the major operational application themes, in which India has extensively used remote sensing data are agriculture, forestry, water resources, land use, urban sprawl, geology, environment, coastal zone, marine resources, snow and glacier, disaster monitoring and mitigation, infrastructure development, etc. The paper reviews RS techniques and applications carried out using both optical and microwave sensors. It also analyses the gap areas and discusses the future perspectives. [ABSTRACT FROM AUTHOR]

The article reports on keloids and hypertrophic scars which are fibroproliferative disorders that occur after trauma, inflammation, surgery and burns. They are characterized by excess deposition of collagen in the dermis. Keloids occur in individuals with a familial disposition among the Blacks, Hispanics and Orientals.

Hypertrophic scar and keloids have affected patients and frustrated physicians for centuries. Hypertrophic scar (HSc) and keloids are a major problem for patients who survive extensive thermal and traumatic skin injuries. HSc and other fibroproliferative disorders are associated with excessive accumulation of collagen and extracellular matrix proteins due to an imbalance between synthesis and degradation. The therapeutic management of hypertrophic scars and keloids include occlusive dressings, compression therapy, intralesional corticosteroid injections, cryosurgery, excision, radiation therapy, laser therapy, interferon therapy and other promising lesser known therapies directed at collagen synthesis. In this study we investigated the effect of phenergan (promethazine hydrochloride) as one of the most potent histamine antagonists on cell proliferation, DNA synthesis and collagen production in fibroblast isolated from human post burn hypertrophic scar, keloids and normal skin. The proliferation of normal skin fibroblast was slightly decreased but hypertrophic scar and keloids showed significant (p<0.001) level of decrease after 72 hours of phenergan (750 μM) treatment. The results of DNA synthesis also significantly (p<0.001) decreased in hypertrophic scar and keloid fibroblasts. Phenergan (1.5 mM) decreased the collagen synthesis upto 61% and 66% in HSc and keloids in comparison to normal skin fibroblast, which showed reduction of 38% after 72 hours. Improved understanding of such regulatory mechanisms may eventually be of therapeutic significance in the control of hypertrophic scar and keloids. [ABSTRACT FROM AUTHOR]

Compounds of nominal compositions Cr1.8Ti0.2O3+δ, Cr1.7Fe0.1Ti0.2O3+δ and Cr1.78Mn0.02Ti0.2O3+δ have been prepared by a co-precipitation method and characterized by X-ray powder diffraction and thermal analyses. The sensor characteristics of these nominal compositions are reported. The sensors fabricated using the powders calcined at 773, 873, 973 and 1273 K were tested for their sensing properties towards ammonia, hydrogen and liquefied petroleum gas (LPG). The influence of calcination temperature and the incorporation of iron and manganese oxides in enhancing the sensitivity are discussed. [Copyright &y& Elsevier]

The proton compounds Ba2In2(1-x)Ti2xO4+2x(OH)y [0≤x≤1; y≤2(1-x)] were prepared by reacting Ba2In2(1-x)Ti2xO5+x⧠1-x (0≤x≤1) phases with water vapor at ∼200 °C. For 0≤x≤0.20, the filling of oxygen vacancies is almost complete. For larger x values, it decreases significantly down to ∼30% only for x=0.7. The crystal structure of the end member Ba2In2O4(OH)2 (x=0) was reinvestigated by a combination of techniques including 1H and 2D NMR and electron, X-ray and neutron diffraction. The actual cell is eight times larger than that previously published. The structure analysis confirms that the sheet consisting of parallel chains of In(2)O4 tetrahedra and parallel rows of oxygen vacancies in the parent structure of Ba2In2O5⧠ has been converted into a In(2)O6 octahedral perovskite-like sheet. It demonstrates that the protons are bonded only to the O atoms around this In(2) site.When x increases, the change in reduced perovskite cell volume, concomitant with the water uptake, remains small for x<0.25 and negligible for larger x values.The proton conductivity was measured between room temperature and 180 °C. The highest conductivity at 180 °C, σ180≈10-6 S cm-1, is observed for x∼0.3. [Copyright &y& Elsevier]

Ba2In2(1-x)Ti2xO5+x⧠1-x (0≤x≤1) compounds have been prepared by solid state reaction. At room temperature (RT), when x increases, the progressive filling of oxygen vacancies, concomitant with the substitution of Ti for In, first induces (for 0

Age, aetiology of burn, percentage body surface area burnt and post-burn sequelae have a direct relationship to the rehabilitative necessity in burnt children in a developing country--India. In spite of the gross disfigurements and sequelae, only adolescent children required psychosocial rehabilitation. These are the results following a retrospective analysis of 459 paediatric burn patients in Madras, India. [ABSTRACT FROM AUTHOR]

Age, aetiology of burn, percentage body surface area burnt and post-burn sequelae have a direct relationship to the rehabilitative necessity in burnt children in a developing country--India. In spite of the gross disfigurements and sequelae, only adolescent children required psychosocial rehabilitation. These are the results following a retrospective analysis of 459 paediatric burn patients in Madras, India. [ABSTRACT FROM AUTHOR]

This paper proposes a new hypothesis in relation to developing a technology transfer (TT) model. The international transfer of technology is modelled in competitive general dynamic framework in which we first build a simple model for technology growth, generalise it to TT and finally develop a specific dynamic model to incorporate certain function governing the transfer of technology. The new model can be used as a decision making tool for measuring and testing the TT potentials that exist between a transferor and a transferee. An application of this model is demonstrated by an example based on selected APEC’s countries real data set. [Copyright &y& Elsevier]

This article focuses on the development of a multiobjective optimization algorithm for a tubular reactor–regenerator system with a moving deactivating catalyst. The task is to find the optimal temperature profile along the tubular reactor, catalyst recycle ratio, and the regeneration capacity for maximizing the process profit flux, selectivity, and conversion. A new heuristic technique, viz, ant colony optimization method has been employed to obtain the Pareto optimal set of solutions. [ABSTRACT FROM AUTHOR]

The paper illustrates the application of the ant colony optimization algorithm to solve both continuous function and combinatorial optimization problems in reliability engineering. The ant algorithm is combined with the strength Pareto fitness assignment procedure to handle multiobjective problems. Further, a clustering procedure has been applied to prune the Pareto set and to maintain diversity. Benchmark case examples show the superiority of the ant algorithm to such problems. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

By virtue of its high spectral resolution (10 nm) and five narrow bands in the red-near infrared (615-815 nm) spectral domain, IRS-P3 MOS-B offers potential in the study of the spectral shifts of the inflection point of the red edge. The detection of red edge shifts on the basis of spectral measurements carried out using data from space-borne platforms is associated with many issues such as atmospheric effects, soil background reflectance and angular anisotropic conditions. In the present experiment, efforts have been made to address these issues and also to study the biophysical nature of spectral shifts. These spectral shifts were derived from the reflectance spectra of rice crops grown under stressed and unstressed conditions. Near real time field experiments were conducted to validate radiance measurements, including the spectral shifts. Experimental results demonstrate that: (i) there is a definite shift (to the extent of 37 nm) towards shorter wavelengths; (ii) the shift is closely associated with stress parameters; (iii) the nature and position of the shifts are invariant, irrespective of the measurements either being made by field instruments or by space-borne imaging sensors. The field experiment, which was conducted to validate IRS-P3: MOS-B data for land applications, clearly establishes the link of red edge inflection points (λ[sub i]) to the key biophysical parameters such as Leaf Area Index (LAI), soil moisture variations (Δθ) and crop nitrogen content (N[sub T]). The study on inflection points derived from samples of 20, 15, 10 and 5 channel combinations in the red-near infrared spectral domain reveals that, even with five channels of IRS P3: MOS-B, it is possible to retrieve λ[sub i] within the allowable range of errors. The combination of five spectral channels, which corresponds to IRS-P3: MOS-B data, has also been found to be sensitive, to a certain extent, to the biophysical parameters. Hence the dynamic range of λ[sub i] extracted from this combination addresses issues related to vegetation stress. Coupling the corresponding Normalized Difference Vegetation Index (NDVI) with λ[sub i] has significantly improved the spectral estimates of biophysical variables of the land surface. The physical basis of coupling has also been discussed. However, the small dynamic range of λ[sub i] requires further studies in which spectral and radiometric resolutions of imaging sensors could be appropriately defined. [ABSTRACT FROM AUTHOR]

The Indian Earth Observations Program, over the past three decades, has been mainly driven by the national need of natural resources management, infrastructure development, environment monitoring and disaster management support. With an array of seven Indian Remote Sensing Satellites (IRS), national development support has been supported, through a well-knit institutional framework of a National Natural Resources Management System (NNRMS), a wide variety of applications developed as an inter-agency effort over the past 20 years. Now, the capacity of the programme has been extended into the global arena and IRS is providing operational data services to the global user community.The future Earth Observation Systems will have to take into consideration the aspects related to the commercialisation and standardisation of programmes world-over; transitioning into a business environment; data continuity and the need to monitor processes rather than events. Technological changes are also going to re-define many of the concepts of observation from space and issues like spatial resolution, spectral resolution and temporal resolution may no more be a concern for observation systems.ISRO is presently defining a strategy for the Indian EO Programme that will chart the progress with a vision for the next 25 years. Based on a thorough analysis, the observation needs of the future are planned and presently systems design and implementation are underway. The Need Analysis has been done keeping in mind the Global change applications; Mapping and Cartographic applications; Natural Resources and Environmental management applications etc. Issues related to defining the space and data acquisition as a national “public good”, costing of data products and services and evolving a commercial remote sensing policy have been addressed for providing the overall thrust of the Indian Earth Observations program. The paper discusses the strategy adopted for assessing the future user requirements and also for defining the future Indian missions - which are applications specific solutions. The paper discusses the evolution of the strategy, in the early stages now, and its transition to support a two-pronged strategy of supporting national development and, at the same time, developing a commercial business enterprise. The need to generate newer user segments and develop newer services and products has been recognised from the utilisation point of view. The impact on utilisation accruing from these proposed missions has also been assessed and is discussed in the paper. [Copyright &y& Elsevier]

Deals with a study which presented a total solution approach through the Indian Remote Sensing Satellite to address sustainable management of the ecosystem. Generation of a high resolution synthetic image; Intersensor calibration and validation; Spatial heterogeneity, scale anomalies and uncertainties; Conclusion.

• A methodology to analyse low-level adsorption on working electrode by EIS and XPS using a three-electrode configuration. • An in-house fabricated three electrode system is used to understand the surface mechanism. • A change in the impedance characteristics will reveal the state of electrolyte-electrode interface during sensing. • XPS studies carried out on the surface gives information regarding the by-product formed which can be envisaged as a change in the chemical environment of the material. [Display omitted] A three-electrode configuration was used to study the electrode-electrolyte interface of AgI based potentiometric cells. The study of the side reactions on the electrolyte surface was done by changing the ambience of electrolyte in the cell from air to halogen. Comparing exchange current density calculated for AgI in the different gases gives insight into the feasibility of sensing towards the particular gas. XPS investigation revealed the formation of by-products that can change the chemical environment of the material. [ABSTRACT FROM AUTHOR]

We report resonant cavity infrared detectors with a peak wavelength of 4.54–4.58 μm that combine external quantum efficiency (EQE) exceeding 70% with spectral bandwidth 20–40 nm and ≤2% EQE at all non-resonance wavelengths between 4 and 5 μm. A 300-nm-thick absorber assures that most of the radiation propagating in the cavity produces photocurrent rather than parasitic loss. The cavity is formed by heterogeneously bonding a midwave infrared (MWIR) nBn detector chip to a GaAs/AlGaAs distributed Bragg reflector, etching away the GaSb substrate, forming mesas with diameter ≈100 μm, depositing a Ge spacer, and then depositing a single-period Ge-SiO2 top mirror. At all temperatures between 125 and 300 K, the responsivity at 150 mV bias exceeds 2.2 A/W and the EQE exceeds 61%. When the thermal background current for a realistic system scenario with f/4 optic that views a 300 K scene is derived from the observed EQE spectra, the resulting specific detectivity D* of 7.5 × 1012 cmHz½/W at 125 K operating temperature is 4.5 times higher than for a state-of-the-art broadband MWIR HgCdTe device. Simulations of the cavity performance indicate that EQE > 90% may be feasible following minimization of parasitic optical loss and maximization of the photocarrier collection efficiency. Potential applications include free space optical communication, chemical sensing, on-chip spectroscopy, and hyperspectral imaging. [ABSTRACT FROM AUTHOR]

• Indirect on-line sensing of mercury and zinc vapour using a YSZ based potentiometric oxygen sensor. • The measurement of oxygen concentration before and after reaction with metal vapour using potentiometric oxygen sensor. • Vapour pressure values estimated corroborate with literature. Indirect on-line estimation of metal vapours of Hg and Zn using YSZ based electrochemical oxygen sensor is attempted. Change in oxygen partial pressure, in presence and absence of these metals vapours, enables the estimation by using oxygen sensor. Using this method, the Zn metal vapours has been detected down to 13.3 ± 0.7 vppm and for Hg vapour, the lowest detection limit is 68.1 ± 0.7 vppm. The measured vapour pressure is in agreement with the predicted values. [ABSTRACT FROM AUTHOR]

Demonstrated are 1060 nm microelectromechanical-systems-based tunable vertical-cavity surface-emitting lasers (MEMS-VCSELs) with a 100 nm continuous tuning range under repetitively scanned operation at rates beyond 500 kHz and a 90 nm continuous tuning range under static operation. These devices employ a thin strained InGaAs multiple quantum well active region integrated with a fully oxidised GaAs/AlxOy bottom mirror and a suspended dielectric top mirror. The devices are optically pumped via 850 nm light. These ultra-widely tunable lasers represent the first MEMS-VCSELs reported in this wavelength range, and are ideally suited for application in ophthalmic swept-source optical coherence tomography. [ABSTRACT FROM AUTHOR]

Microelectromechanical-systems-based vertical-cavity surface-emitting lasers (MEMS-VCSELs) capable of a 150 nm continuous tuning range near 1310 nm are demonstrated. These devices employ a thin optically pumped active region structure with large free-spectral range, which promotes wide and continuous tuning. To achieve VCSEL emission at 1310 nm, a wide-gain-bandwidth indium phosphide-based multiple quantum well active region is combined with a wide-bandwidth fully oxidised GaAs-based mirror through wafer bonding, with tuning enabled by a suspended dielectric top mirror. These devices are capable of being scanned over the entire tuning range at frequencies up to 500 kHz, making them ideal for applications such as swept source optical coherence tomography and high-speed transient spectroscopy. [ABSTRACT FROM AUTHOR]

Plastic surgery continues to maintain a prominent presence in the evolution of male genital reconstruction. In this case report, we are presenting a case of post-electric burn with a total loss of penis. Sustaining other major injuries following an electric burn with loss of right upper limb and extensive tissue damage to left upper limb, abdomen and both thighs, this young male patient was initially managed from life-threatening problems. With many options closed following a major electric burn and its acute management, penile and urethral reconstruction was a unique and a great challenge in this patient. Heeding to the patient's wish of male pattern micturition, we had performed a successful reconstruction of urethra and entire phallus with groin flap. [ABSTRACT FROM AUTHOR]

Demonstrates the broadband tunability in a semiconductor laser using sampled gratings. Ratio of the fractional tuning range to the fractional index change; Characteristics of the sampled gratings; Magnitude of indium gallium arsenic phosphide laser tuning.

Performance of a wide range H 2 sensor made of thin film of Pd dispersed with silver nanoparticles and a buffer layer of Cr for Al 2 O 3 substrate having a typical working range of 800 ppm-4% H 2 in argon, is presented. Thin films of Cr, Pd and nanoparticles of Ag have all been deposited sequentially as multilayers using pulsed laser deposition method. GI-XRD confirms the formation of face centered cubic Pd. Pd is in elemental state in the as-deposited multilayer while Ag exhibits both elemental and +1 oxidation state in Ag–Pd/Cr which upon H 2 conditioning at 200 °C becomes elemental Ag. Cr buffer layer despite very effective in preventing delamination of Pd films during hydrogen intake, it leads to the loss of H 2 sensing properties. Dispersion of silver nanoparticles on the sensing surface of Pd restores the H 2 sensing properties of Pd/Cr. The results of Ag–Pd/Cr/Al 2 O 3 are compared with those of Pd/Cr/Al 2 O 3 and Pd/Al 2 O 3 and the role of Ag nanoparticles in sensing is highlighted. Image 1 • Sequential deposition of Cr, Pd and Ag on Al 2 O 3 is carried out using PLD. • Nanoparticles of Ag on Pd/Cr restores the gas sensing properties of Pd/Cr. • Upper limit of H 2 detection of Ag–Pd/Cr multilayer is extended to 4% in argon. • The H 2 response of Ag–Pd/Cr multilayer is consistent and reproducible. [ABSTRACT FROM AUTHOR]

Presently several beta emitting radionuclides are in use as brachytherapy sources, due to their inherent advantages of short-range radiation dose delivery compared to their gamma emitting counterparts. 90Y is one of the well-known hard beta-emitting radioisotopes for the therapeutic application of radioactivity. Among various other modalities, 90Y resin microsphere as a brachytherapy source has its application for liver cancer. In the present study, 90Y was recovered from 235,238U,239Pu(nfast,f)90Sr(β−)90Y using Sr selective crown ether followed by quick purification using the Ion Chromatography technique. The purified 90Y was labelled in strong cation exchange resin to form 90Y resin microsphere. Various quality control parameters, e.g., water solubility, chemical, radionuclidic purity, and half-life, were verified using Gamma spectrometry, Cerenkov, and Liquid Scintillation Counting techniques. The obtained half-life was 64.05 h, which is in excellent agreement with the literature and is indirect evidence of the very high radionuclidic purity of the sample. A rapid method for the synthesis of 90Y resin microsphere brachytherapy source is being reported for the first time after its recovery from irradiated fast reactor fuel dissolver solution. After the separation of 90Sr along with trace level impurities inside the hot cell, simultaneous purification of parent 90Sr and daughter 90Y using single-stage Ion Chromatography step takes 15–25 min only in comparison to 24 h or more time using multistage conventional Ion exchange chromatography column, which saves the separation time and in turn, increase the yield of 90Y per separation campaign. [ABSTRACT FROM AUTHOR]

Identification of a failed fuel subassembly due to the dry rupture of its fuel pin in prototype fast breeder reactor is one of the safety protocols to be standardized for its safe operation for which interaction of fission gases with liquid sodium was studied. This paper reports the studies on the feasibility of detection of fission gases in presence of sodium as well as separation of fission gases out of liquid sodium through Ar purge in a prototypical sodium module with 300 mL of Na. The resultant gases were adsorbed on activated charcoal and determined the activity of fission gases using high resolution gamma spectrometry. Quantitative recovery of fission gases from sodium matrix in the range of sub-picogram levels was established. [ABSTRACT FROM AUTHOR]

For employing strontium incorporated sodium iron titanate (Sr-SIT) in applications related to aqueous environments, the assessment of leach resistance of constituent elements assumes significance. The sodium iron titanate was prepared by the conventional co-precipitation method, and an ion exchange method was adopted for introducing strontium. 28-day-long Soxhlet leaching studies were undertaken for irradiated and unirradiated sintered solid pellets of Sr-SIT. The leaching propensities of the Sr-SIT constituents were analyzed by ICP-OES and neutron activation analysis respectively, for the unirradiated and irradiated Sr-SIT. These studies established the chemical stability of Sr-SIT towards leaching. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Thin films of PbS deposited by pulsed laser deposition under in-situ argon pressure. • Oxygen-free PbS thin film confirmed by X-ray photoelectron spectroscopy. • Hall studies show p-type conductivity with a carrier concentration of 1011 cm−3 at 298 K. Abstract Thin films of PbS were grown on (0 1 2) LaAlO 3 by pulsed laser deposition and the deposition parameters were optimized. Films deposited at 553 K under the in-situ argon pressure of 10−1 mbar were granular having an average crystallite size of 25 nm with a texturing along (2 0 0) direction. Pb 4f and S 2p levels of PbS reveal Lead in +2 and Sulphur in −2 state and there was no evidence for oxygen contamination. Hall results revealed p-type conductivity with the carrier concentration of about 1011 cm−3 and a four-probe conductivity of 2 × 10−4 Ω−1 cm−1 at room temperature. The use of PLD for growing thin films of a non-oxide based material is demonstrated. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 72-year-old woman who underwent a laparorobotic pancreaticoduodenectomy using the da Vinci Surgical System for the removal of a 4-centimeter (cm) ampullary adenoma. The devices used include the comparable scissors-type used to aid in endoscopic submucosal dissection of both gastric and colorectal neoplasms. It notes that it is the first case in humans demonstrating safe and effective use of endoscopic scissors approved by the Food and Drug Administration.

Review: 53 refs. [ABSTRACT FROM AUTHOR]

Primary components of sodium cooled fast reactors get contaminated due to activity transport that occurs from core to out-of-core through coolant which causes activity burden to the personnel during operation and maintenance. To minimize the MAN-REM issues it is necessary to scavenge 54Mn, 60Co and 65Zn which are of major radiological concern from primary sodium using a compact device. Experimental studies were performed at various durations and temperatures with nickel as single trap material to trap the radionuclides simultaneously and its uptake was estimated. Trapping efficiency of porous and non-porous Ni at 773 K was estimated using radiotracer technique. [ABSTRACT FROM AUTHOR]

The Hydrogen in Argon Detectors (HADs) working on the principle of thermal conductivity difference between argon (reference) and argon + H2 (sample) in the cover gas of a sodium-cooled fast breeder reactor using the Wheatstone bridge circuit. The output of HAD is very sensitive to the gas flow rate and to the variation in ambient temperature. The RMSnoise of current was brought within ±1 µA by a constant current source across the bridge. The temperature correction factor fed in the processor brought down the RMSnoise in the HAD signal within ±2.4 mV than the uncorrected one having RMSnoise of ±230 mV. The filtered noise of HAD facilitates enhancing the detection limit of HAD down to 30 ppm (3σ) of hydrogen in argon. [ABSTRACT FROM AUTHOR]

Review: 886 refs. [ABSTRACT FROM AUTHOR]

Abstract A series of zirconium substituted barium thorates (BaTh 1-x Zr x O 3, where x = 0–0.4) were synthesized via modified solid-state reaction. The electrical conducting behavior in the oxygen and hydrogen atmospheres was investigated in the temperature range of 300–600 °C. The chemical stability towards CO 2 among these compositions was studied at 400 and 600 °C. All the Zr substituted BaThO 3 exhibited higher conductivity than pristine BaThO 3 in the oxygen atmosphere. BaTh 0.9 Zr 0.1 O 3 was found to exhibit higher conductivity in the hydrogen atmosphere with better chemical resistivity towards CO 2 at 400 °C over other compositions. [ABSTRACT FROM AUTHOR]

Pristine as well as ytterbium substituted barium thorates, BaTh 1-x Yb x O 3-δ (x = 0–0.2) were synthesized using a modified solid state method. Electrical conductivity behavior of the sintered specimens in various atmospheres in temperature range from 300 to 600 °C was explained. Substitution of ytterbium into barium thorate was found to enhance its conductivity in oxygen ambience. The same was found to be enhanced further when the ambience was changed to hydrogen for the composition up to x = 0.1 but, marginally decreased from thereon for the composition with x = 0.15. Retention of hydrogen in thorate matrix was elucidated. [ABSTRACT FROM AUTHOR]

Zirconate and phosphate based lithium ion conductors namely, Li 2 ZrO 3, Li 2-4x Zr 1+x (PO 4 ) 2 (x = 0, 0.125, 0.25, 0.35, 0.45) were prepared and characterized with powder X-ray diffraction and electrical conductivity. Li 2 ZrO 3 exhibited the lowest conductivity and in phosphates, it increased initially with increase in lithium concentration and then decreased. The transport number of lithium deduced from blocking electrode method was found to be in the range of 0.79 to 0.89 for Li 2 ZrO 3 , whereas for phosphates with x = 0, 0.125 and 0.35, t Li + was better than 0.98. Li 0.6 Zr 1.35 (PO 4 ) 2 , was found compatible in lead-lithium alloys. [ABSTRACT FROM AUTHOR]

Liquid sodium is the heat transport medium in fast breeder reactors due to its favorable chemical, physical, and nuclear properties. Wetting of liquid sodium with the material of reactor components is essential for the effective functioning of the reactor. Liquid sodium wetting plays a crucial role, such as in (i) heat transfer and (ii) image reconstruction under sodium ultrasonic scanners. Contact angle is the inverse measure of the wetting of liquids over solid surfaces. A contact angle measurement system was set up in an inert atmosphere glow box to study the wetting behavior of liquid sodium on reactor materials. The contact angle of liquid sodium on nickel surface was measured as a function of temperature, and the results obtained were found to be in good agreement with the literature values. The contact angle of liquid sodium on SS316LN as a function of temperature was measured for the first time using this facility. [ABSTRACT FROM AUTHOR]