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We experimentally demonstrate a new method to determine the polarization properties of piezoelectric nanocomposite materials using fiber-optic cantilever beam deflection principle. We used an optimized composition of BiFe0.9Co0.1O3 nanoparticles as a sample coated on a selected segment of the exit end of a single-mode optical fiber to devise the beam-deflecting cantilever assembly in a surrounding electric field. Performing series of experiments by systematically varying the associated parameters, namely coated length, coating thickness of deflecting fiber probe, polarization properties at different electric field intensities is determined. As an initial attempt, we devise a fiber-optic double-slit type arrangement and calculate the polarization values by measuring the fringe-width variation of interference pattern as a function of applied electric field. Through a progressive experimental development, we embed the fiber beam deflection transducer in a fiber-to-fiber signal transmission configuration. Polarization values are now determined in terms of transmitted power variation with applied electric field. The sensitivity is further enhanced by a cascaded assembly of cantilevers. We report a sensitivity ~ 0.067 kV/cm using our set-up and determine the polarization values that are known otherwise from the literature, thereby establishing the efficacy of this new approach.

Introduction: High prevalence of Hepatitis C virus (HCV) has been reported among the dialysis patients throughout the world. Aim of the study was to evaluate prevalence of HCV in haemodialysis patients at tertiary care hospitals of Pune, Maharashtra, India. Materials and Methods: A cross sectional study design was conducted among 250 patients from five dialysis centres in pune city including both government and corporate hospitals who reported to the nephrology department for haemodialysis in a period of one year. Cases were studied in detail about complete history, clinical and demographical profile as well as several biochemical parameters. A predesigned, pretested questionnaire was used for data collection. SPSS 21.0 version software was used to analyze the data. Result: Prevalence of HCV Infection in patients on hemodialysis was found to be (18.8%). Out of total anti-HCV antibody positive patients (59.6%) were found to be male and (40.4%) were female. Out of total anti-HCV antibody positive cases (72.3%) had been on dialysis for more than 5 years. About (68.1%) of total positive cases received blood transfusion once or more in life time. Conclusion: In developing countries with a high endemic background of HCV infection surveillance programs and efforts to increase awareness, improve diagnosis and facilitate treatment of acute HCV will have far reaching implications for the management of chronic HCV. Thus preventive measures and the adherence to universal precautions for HCV control remain a priority. Keywords: Seroprevalence, Hepatitis C, Haemodialysis, Tertiary care hospitals.

The world is currently witnessing a pandemic crisis caused by SARS CoV-2 having its origin in Wuhan, China Transformation from epidemic to pandemic within a very short time-gap resulting in massive global mortality has created a sudden global deadlock affecting both human health and wealth Clinical symptoms expressed by affected patients include dry cough, dyspnea, fever, bilateral lung infiltration and ultimately severe acute respiratory distress in advanced stages The disease is spread over 150 countries and termed as COVID-19 by the World Health Organization (W H O) As per W H O report on 2nd May 2020 there are over 3000000 infected cases distributed throughout the globe claiming more than 200000 lives Mortality rate is accelerating at high speed and presently crossing 6% The entire global healthcare system is exposed and found to be inadequate to mitigate the deadly virus At present there is no medicine or vaccine available or clinically proven for COVID-19 management However, the global research spotlight is now focused on development of drugs or vaccine against the virus This has created a long pipeline of such agents which are now under preclinical or clinical evaluation stage Some existing drugs are also under efficacy evaluations against COVID-19 whereas some are allowed to be used as a prophylactic measure WHO has framed clear guidelines for all countries to manage the spread of the virus and these are being implemented through existing government & regulatory bodies of specific countries The present work will give detailed outline on the pandemic spread, transmission mode, therapeutic strategies and its impact on day to day human life

Cancer management presents multifarious problems. Triple negative breast cancer (TNBC) is associated with inaccurate prognosis and limited chemotherapeutic options. Betulinic acid (BA) prevents angiogenesis and causes apoptosis of TNBC cells. NIH recommends BA for rapid access in cancer chemotherapy because of its cell-specific toxicity. BA however faces major challenges in therapeutic practices due to its limited solubility and cellular entree. We report lactoferrin (Lf) attached BA nanoparticles (Lf-BAnp) for rapid delivery in triple negative breast (MDA-MB-231) and laryngeal (HEp-2) cancer cell types. Lf association was confirmed by SDS-PAGE and FT-IR analysis. Average hydrodynamic size of Lf-BAnp was 147.7 ± 6.20 nm with ζ potential of -28.51 ± 3.52 mV. BA entrapment efficiency was 75.38 ± 2.70% and the release mechanism followed non-fickian pattern. Impact of Lf-BAnp on cell cycle and cytotoxicity of triple negative breast cancer and its metastatic site laryngeal cancer cell lines were analyzed. Lf-BAnp demonstrated strong anti-proliferative and cytotoxic effects, along with increased sub-G

In this paper, a stable hybrid plasmonic optical directional coupler based on an embedded silver nanostructure that can offer a power transfer up to 95% is presented. This optimum power transfer is obtained at an outer edge-to-edge separation of 0.58 µm between the two waveguides. The obtained propagation loss is as low as 0.0863 dB/µm. The electric field distributions of the symmetric and antisymmetric modes of the coupler are compared, and the transmission characteristics are studied in detail using the finite element method. The performances of the directional coupler have been further characterized in terms of excess loss, coupling degree, and directionality. The shortest coupling length at which the maximum power coupling occurs is obtained as 2.488 µm. The proposed compact directional coupler features good field confinement and low propagation loss, which opens the door for many device applications in photonic-integrated circuits and optoelectronic industries.

IntroductionThe rising economic burden of cancer on healthcare system and patients in India has led to the increased demand for evidence in order to inform policy decisions such as drug price regulation, setting reimbursement package rates under publicly financed health insurance schemes and prioritising available resources to maximise value of investments in health. Economic evaluations are an integral component of this important evidence. Lack of existing evidence on healthcare costs and health-related quality of life (HRQOL) makes conducting economic evaluations a very challenging task. Therefore, it is imperative to develop a national database for health expenditure and HRQOL for cancer.Methods and analysisThe present study proposes to develop a National Cancer Database for Cost and Quality of Life (CaDCQoL) in India. The healthcare costs will be estimated using a patient perspective. A cross-sectional study will be conducted to assess the direct out-of-pocket expenditure (OOPE), indirect cost and HRQOL among cancer patients who will be recruited at seven leading cancer centres from six states in India. Mean OOPE and HRQOL scores will be estimated by cancer site, stage of disease and type of treatment. Economic impact of cancer care on household financial risk protection will be assessed by estimating prevalence of catastrophic health expenditures and impoverishment. The national database would serve as a unique open access data repository to derive estimates of cancer-related OOPE and HRQOL. These estimates would be useful in conducting future cost-effectiveness analyses of management strategies for value-based cancer care.Ethics and disseminationApproval was granted by Institutional Ethics Committee vide letter no. PGI/IEC-03/2020-1565 of Post Graduate Institute of Medical Education and Research, Chandigarh, India. The study results will be published in peer-reviewed journals and presented to the policymakers at national level.

The healthcare sector in India is witnessing unprecedented advancement. Tissue engineering has become an integral part of healthcare and medicine, particularly where treatments involve functional restoration of any injured or deceased part of the body. Not falling behind much with the progressing medical and healthcare sector of India, tissue engineering is also gaining momentum in the country. Out of several arenas of tissue engineering, India has made its mark in orthopedic and bone regeneration, cosmetic and skin regeneration, and very importantly neural regeneration. There are several articles reviewing the progress and prospects of orthopedic and skin regeneration research in India. However, there is no systematic review on progress, prospects, and pitfalls associated with neural tissue engineering in Indian context. The existing ones mainly focus on the technical advancements in the field from a global perspective. Therefore, it is worthwhile to have an organized look at the evolving neural tissue engineering landscape of India. This review will walk the readers systematically through different aspects of the topic. The review starts with an introduction to the nervous system to help readers appreciate the complexity that must be dealt with while engineering neural tissue. This is followed with a global picture of the neural tissue engineering, prominent research groups working on neural tissue engineering in India, factors that have and are currently molding the prospects of this field, and concluding with an overall perspective on present and future of neural tissue engineering in India.

The present study entails the toxicity evaluation of 7-methyl xanthine (7-MX), first of its kind molecule found effective in phase II clinical trials for the treatment of myopia, in comparison to other clinically used xanthines i.e., caffeine and theobromine. For acute toxicity evaluation, 7-MX was administered orally in two rodent species (rat and mice) at the doses of 300 mg/kg and 2000 mg/kg and for repeated dose 28-d oral toxicity, at 250, 500, and 1000 mg/kg in rats. Further, cellular toxicity was evaluated in normal breast epithelial (fR2), rat brain C6 glioma (C6 glioma) and human colorectal (Caco-2) cell lines. Also, the cell uptake assay to determine the intestinal permeability of drug was performed in Caco-2 cells. In acute toxicity, 7-MX treatment showed no mortality and toxicity, whereas 66.6% (mice) and 33.3% (rat) mortality was observed in both caffeine and theobromine treatment groups. In repeated dose 28-d oral toxicity, 7-MX treatment was found to have no-observed-adverse-effect level up to the dose of 1000 mg/kg in the present study conducted as per OECD guidelines 407. Also, very high IC

We devise a tunable cavity fiber Fabry-Perot magnetometer circuit hosting cantilever-deflection using cobalt-doped nickel ferrite coated optical fiber as cantilever. The magnetic field induced modulation of cavity length of Fabry-Perot due to bending of the fiber-cantilever in the transverse direction as observed experimentally is modeled using the fiber-to-fiber coupling signature in the platform of Fabry-Perot multiple-reflection-transmission analysis. By introducing in-house fabricated silver-coated fiber-mirror in this configuration, sensitivity is improved by optimizing the coating-process through real-time monitoring towards achieving a maximum reflectivity of 95%. We demonstrate a high-performance and tunable sensitivity three-mirror Fabry-Perot assembly of fiber-cantilever-deflection magnetometer capable of detecting ˜mT or even lower in the dynamic range of 0–100 m T.

Background The depletion of fossil fuel and its huge environmental problem are currently a concern for a scientific community in the area of energy engineering. This opened research opportunities for searching alternate renewable energy sources especially biofuel production from lignocellulose biomass resources. The main objective of this paper is to review the delignification and hydrolysis capabilities of microorganisms (bacteria and fungi). Results Currently, different types of lignocellulose biomass pretreatment technologies are available. All of the technologies are either in lab scale or in pilot scale. Among the pretreatment technologies, biological pretreatments attract many attentions because of their eco-friendly advantages, performed at a mild temperature and do not produce inhibitory compounds during the pretreatment process. Industrial-scale biofuel production using biological delignification and hydrolysis process is still at lab scale, and intensive research works are required. The cost of biofuel production from lignocellulose biomass is currently expensive. Conclusion Searching for the best microbial strains having efficient lignin-degrading and polysaccharide-hydrolyzing capabilities is vital to realize industrial-scale biofuel production from lignocellulose biomass. Process optimization along with genetic engineering of microorganisms is seen as a potential for biofuel production from lignocellulose biomass.

Background Worldwide prevalence of Hepatitis C virus (HCV) infection hemodialysis (HD) ranges from 1 to 84.6% with serious complications. Assessment of prevalence, risk factors, and genotyping of HCV infection in patient on HD was carried out at Pune, India. Methods A total of 250 patients on HD from five HD centers were recruited and tested for anti-HCV antibody using third-generation enzyme-linked immunosorbent assay (ELISA). Qualitative HCV RNA detection was carried out by nested reverse transcriptase polymerase chain reaction (RT-PCR). Genotyping and sequencing were carried out using the BigDye Terminator cycle sequencing ready reaction kit. Results Mean age of patients was 47.3 years. Forty-seven cases out of a total of 250 were reactor for HCV antibody. Overall prevalence rate was 18.8% ranging from 6.7% to 35.6% in the five centers. Of total, 44.1% of females and 13.5% of males were HCV infected. The mean duration of HD in HCV-infected patients was 6.03 years. Prevalence was higher in patients aged > 5 years on HD with higher number of blood transfusions. Thirty-six cases were positive for HCV RNA. Only one HCV RNA was detected among the 203 anti-HCV negative samples. Discordance between antibody and HCV RNA positivity was noted. Seventeen infected cases had changed dialysis centers four times. Thirteen cases were HBsAg positive, of which six cases were coinfected with HCV. Thirty-seven samples were genotyped. Conclusion The predominant genotype was 1a (54.1%) followed by 1b (43.2%) and 3a (2.7%). Highest prevalence of HCV (35.6%) and intracenter PNI of 99.3% of genotype 1b (84.6%) in center 3 indicates a possible nosocomial transmission.

Angiogenesis-mediated neovascularization in the eye is usually associated with visual complications. Pathological angiogenesis is particularly prominent in the retina in the settings of proliferative diabetic retinopathy, in which it can lead to permanent loss of vision. In this study, by bioinformatics analyses, we provide evidence for elevated expression of actin-binding protein PFN1 (profilin1) in the retinal vascular endothelial cells (VECs) of individuals with proliferative diabetic retinopathy, findings further supported by gene expression analyses for PFN1 in experimentally induced abnormal retinal neovascularization in an oxygen-induced retinopathy murine model. We observed that in a conditional knockout mouse model, postnatal deletion of the Pfn1 gene in VECs leads to defects in tip cell activity (marked by impaired filopodial protrusions) and reduced vascular sprouting, resulting in hypovascularization during developmental angiogenesis in the retina. Consistent with these findings, an investigative small molecule compound targeting the PFN1–actin interaction reduced random motility, proliferation, and cord morphogenesis of retinal VECs in vitro and experimentally induced abnormal retinal neovascularization in vivo. In summary, these findings provide the first direct in vivo evidence that PFN1 is required for formation of actin-based protrusive structures and developmental angiogenesis in the retina. The proof of concept of susceptibility of abnormal angiogenesis to small molecule intervention of PFN1–actin interaction reported here lays a conceptual foundation for targeting PFN1 as a possible strategy in angiogenesis-dependent retinal diseases.

We report our experimental realization of fiber-cantilever beam-deflection magnetometer using a series assembly of deflecting fiber-cantilevers for measuring low magnetic field (∼mT) and magnetization of probe nano-particles. Using single-mode fibers coated with optimized cobalt-doped-nickel-ferrite nano-particles, we devise a concatenated twin-fiber-cantilever assembly that identically modulate transmitted fiber-exit beam with varying external magnetic field. We measure surrounding field as low as ∼1 mT and demonstrate gain-multiplication through series-fed signal of fiber-cantilever response. Our cantilever-deflection-transmission analysis is devised to interpret the experimental observation and to determine magnetization of probe-samples. A Sagnac-loop assisted cantilever arrangement is also fabricated and tested that yielded the same sensitivity.

Weather risk perception research lacks multihazard and transcultural datasets. This hypothesis-generating study used a cognitive behavioral approach and Brunswik’s lens model for subjective risk parameters across eight countries. In Germany, Poland, Israel, the United States, Brazil, India, Malaysia, and Australia, 812 field interviews took place with a uniform set of 37 questions about weather interest, media access, elementary meteorological knowledge, weather fear, preparedness, loss due to weather, and sociodemography. The local randomized quota samples were strictly tested for sample errors; however, they cannot be considered representative for individual countries due to sample size and methodology. Highly rated subjective risks included flood, heat, tornado, and lightning. Weather fear was most prominent in the Malaysian sample and lowest in the German. Subjective elements were further explored with bivariate correlations and a multivariate regression analysis. Sociodemography correlated with psychological variables like knowledge, interest, and fear. Fear was related with subjective risk; less educated and informed people were more fearful. A linear regression analysis identified interest, gender, housing type, education, loss due to weather, and local weather access as the significant predictors for preparedness. The level of preparedness was highest in the United States and Australia and lowest in the Malaysian and Brazilian samples. A lack of meteorological training and infrequent loss experiences make media communication important and emphasize the value of repetition for basic information. Elements of this survey can serve to monitor weather-related psychological orientations of vulnerable population groups. Finally, this survey provides a template with which larger representative transcultural multihazard perception studies can be pursued.

In order to tailor the dispersion characteristics and to control the dispersion slope of index-guiding photonic crystal fibers (PCFs), a new controlling technique is reported. Moreover, this technique is applied to design PCF with both near zero and ultraflattened dispersion in a large wavelength range. The birefringence of the fiber is also addressed as the field profile becomes elliptical in the designed fiber. In addition, how the inevitable imprecision introduced during the fabrication process affects the final dispersion profile is investigated. A finite difference method is used to analyze the dispersion properties and the birefringence characteristics of the PCF. Simulation results reveal that ultraflattened dispersion of 0 ± 1.5 ps/(nm.km) can be achieved over a bandwidth of 890 nm in the wavelength region of 1110–2000 nm along with polarization maintaining property.

Information retrieval systems are generally used to find documents that are most appropriate according to some query that comes dynamically from users. In this paper a novel Fuzzy Document based Information Retrieval Model (FDIRM) is proposed for the purpose of Stock Market Index forecasting. The novelty of proposed approach is a modified tf-idf scoring scheme to predict the future trend of the stock market index. The contribution of this paper has two dimensions, 1) In the proposed system the simple time series is converted to an enriched fuzzy linguistic time series with a unique approach of incorporating market sentiment related information along with the price and 2) A unique approach is followed while modeling the information retrieval (IR) system which converts a simple IR system into a forecasting system. From the performance comparison of FDIRM with standard benchmark models it can be affirmed that the proposed model has a potential of becoming a good forecasting model. The stock market data provided by Standard & Poor’s CRISIL NSE Index 50 (CNX NIFTY-50 index) of National Stock Exchange of India (NSE) is used to experiment and validate the proposed model. The authentic data for validation and experimentation is obtained from http://www.nseindia.com which is the official website of NSE. A java program is under construction to implement the model in real-time with graphical users’ interface.

Introduction Mental retardation ranges from the borderline to mild to very severe. Fortunately, the majority (80%) are in the mild range that endows the individual the capacity to lead a simple, yet fruitful life once provided with a means that are conducive to their learning styles. Children with a more severe disorder can achieve remarkably if their unique talents are recognized and nurtured to the fullest. Aim We conducted a study among armed forces personnel in a large city in Maharashtra. This community has many peculiar and special features. They are from different ethnic, religious, and linguistic backgrounds and live together as a cohesive unit. The general socioeconomic and educational awareness toward facilities and concessions available for the differently abled children is assumed to be high. Materials and methods Detailed interaction with 27 parents having special children was conducted and further data were collected. Each parent was individually interviewed. This group was named parents having differently abled children (PHDAC). Group discussions consisting of 15 families in one group that had no special children in the family were conducted. A total of such eight groups (120 families) were, thus, interviewed. This group was named parents having normal children (PHNC). Each family was verbally questioned regarding the facilities available to special children thoroughly and responses were recorded. Results and discussion Overall, it was found that among the PHDAC, the awareness was much better, but some were circumspect of the facilities provided for their wards by the land of the law. Most of them felt that the benefits coming to them were due to their service with the Army. The PHNC were not aware of most of the provisions. However, during the interactions with the researcher, they evinced interest in the matter and were happy to know that special provisions are existent in various Government sectors for special children. How to cite this article Roy C, Roy P. Comparative Evaluation of Awareness among Armed Forces Personnel in Respect of Special Provisions and Benefits Applicable to Children with Disabilities. Indian J Phy Med Rehab 2017;28(2):64-68.

A Cd(II) based 2D metal–organic framework (MOF), [Cd(4-bpd)(SCN)2]n (1) where 4-bpd = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene, has been synthesized and characterized by standard methods including single crystal X-ray diffraction analysis. When it is sandwiched between ITO coated glass and Al, 1 shows interesting conduction properties. The I–V characteristics of the ITO/1/Al configuration measured in the dark and under illumination of incident light exhibit a highly non-linear rectifying behavior, which signifies its Schottky diode character. The conductivity of the configuration is 2.90 × 10−4 S m−1 and 7.16 × 10−4 S m−1 under dark and photoirradiation conditions, respectively. Different parameters have been analyzed and these indicate that 1 can be a promising candidate for light sensing electronic devices. This material has good sensitivity to the light source when switched on/off. Theoretical calculations have been performed to understand the reason for the enhancement of conductivity under illumination of incident light. It has been found that upon irradiation, slight changes in the bond distances of 4-bpd in 1 occur. These changes are related to the considerable decrease in the energy needed for the allowed electronic transition. This may influence the increase of conductivity along with other factors.

We report our experimental demonstration of an all-optical electric field sensing system using single-mode optical fiber based field-induced beam-deflection configuration. For this purpose, we optimize the composition of Cobalt-modified-Bismuth Ferrite (BiFe0.9Co0.1O3) nanoparticles as sensing material which is then coated on a single-mode fiber to form the beam-deflection probe. We perform series of experiments to investigate the response of the system and theoretically model our results. First, devising a fiber-double-slit type experiment, we study the sensing characteristics of the coated fiber-probe in terms of fringe-width variation of the interference pattern with varying applied electric field. This showed a minimum detectable field ~0.2 kV/cm. Towards detecting an even minute change in beam-deflection, we then develop a fiber circuit hosting fiber-to-fiber-coupling of guided fundamental mode and record the detection of an electric field change of ~0.083 kV/cm reproducibly. Finally a two-stage concatenation of this fiber-to-fiber-coupling configuration is demonstrated exhibiting enhanced detection least count as 0.0417 kV/cm. Importantly, the device also enables us to determine the polarisation properties of a sample material. Our reported beam-deflection methodology in electric field sensing is new with useful results and will be potentially promising in designing all-dielectric electric field sensors that will be unique in hazardous and electrically prone environment.

Background HIV estimates for 2009 released by National AIDS Control Organization (NACO) reveals that 2.4 million people in India were living with HIV, 39% being female, 4.4% children and 82.4% adult males between the age group of 15 and 49 years. Persons with host genetic polymorphism CCR5Δ32 mutation are known to be partially or fully resistant to HIV infection. Persons with mutation affecting both the alleles (homozygous) are resistant to HIV infection whereas single allele (heterozygous) polymorphism leads to slower progression to AIDS. CCR5Δ32 mutation is commoner in Caucasians but less prevalent amongst Africans and Asians thereby rendering them susceptible to HIV infection. Method 571 HIV serologically naive subjects from a young and homogenous male population hailing from the seven northeastern states; West Bengal and Gorkha people were selected. All the subjects belonged to a special high risk group, sexually active and typically working in difficult and uncongenial terrain involved in frequent moves including overseas missions. Their family lives are severely disrupted. 181 HIV seropositive cases of which 92 cases that were admitted in a large tertiary care hospital were also included. The distribution of CCR5Δ32 polymorphism amongst both HIV seronegative (HSN) and HIV seropositive study cohorts (HSP) using molecular methods was studied. Results and conclusion There was failure to detect any CCR5Δ32 amongst this study group suggesting that this population from the northeastern India, West Bengal and Gorkha people are not protected by this specific host polymorphism in respect of acquisition of HIV infection as well as progression to AIDS.

The guiding properties of a new type of photonic crystal fibers where air-holes are arranged in a circular pattern (C-PCF) with a silica matrix have been investigated. The dispersion properties of the fiber with different spacing of circle and air-hole diameter have been studied in detail. It is shown that C-PCFs with smaller values of radius and higher air-filling fraction can be used as dispersion compensating fiber. A comparison between fibers with circular and triangular lattice has also been performed, taking into account the dispersion properties and the effective area in the wavelength range between 1200 nm and 1600 nm. C-PCF can better compensate the inline dispersion for both single wavelength and broadband wavelength applications which is a unique property not observed by regular triangular-lattice or square-lattice PCFs. The fiber provides higher effective area, making it a better candidate for high power accumulations in the core of the fiber. The fiber also shows red-shifting of the first zero dispersion wavelength (ZDW), flatter dispersion slope and lower Group Velocity Dispersion (GVD) in the normal dispersion region thereby making it a better candidate for high power nonlinear applications like super-continuum generation, soliton pulse propagation etc . With the above advantages, we have considered a series study of these circular-lattice structures for various geometrical parameters and temporal pulses in order to explore the characteristics of broadband supercontinuum generation. This design study for high power supercontinuum generation will be very helpful for potential application of new sources in various fields like astronomy, climatology, spectroscopy optical tomography and sensing etc . to name a few.

This article deals with the broadband dispersion characteristic of the dual core square lattice Photonic crystal fiber. All the associated geometrical parameters are investigated toward designing broadband dispersion compensating devices for communications wavelength. The design establishes that for broadband dispersion compensation the effect of change of geometrical parameters is less significant. Our numerical analysis establishes that we could design a broadband dispersion of −2500 ps/nm/km which can compensate the dispersion some hundred times to the length of the inline fiber. The design also considers the dispersion slope and kappa values which matches well with the existing SMF-28. Thus our design will be very helpful for a practical purpose. Again applying the power transform from inner core to the outer core at the coupling wavelength for the ultra-negative dispersion, we have studied the design of a possible ASE suppressed amplifier where wavelengths after coupling wavelength can’t be amplified as most of the power goes to the outer core where erbium ions do not exist to be amplified. The principle will be extremely useful for future ASE suppressed amplifier study where we need to amplify only a particular range of wavelengths and suppress the other wavelengths.

The tight modal confinement property with circularly symmetric fundamental mode-field pattern of a ring structured photonic crystal fiber (PCF) is utilized to improve the laser threshold and output characteristics of existing fiber lasers. We perform a detailed study of continuous-wave lasing characteristics in such erbium-doped fiber host by varying associated geometrical and optical parameters towards achieving a high performance and short length fiber laser. A finite difference mode-convergence analysis is implemented to determine the required modal properties of the guiding host, which is then used to solve standard propagation rate equations. The laser properties of the structure considered is compared with equivalent regular triangular-lattice photonic crystal fiber illustrating a significant improvement in the characteristics of fiber lasers reported so far.

In this article, silica based triangular lattice PCF has been investigated toward both narrowband and broadband dispersion compensation for application in the communication wavelength. A dual core structure is obtained by introducing two different air-hole diameters in the cladding of the PCF. Dependence of individual structural parameters toward high negative dispersion (both narrowband and broadband) has been investigated in details with multipole mode based solver. The numerical investigation exhibits narrowband of very large negative dispersion of −37,300 ps/nm/km around the wavelength of 1550 nm. Present investigation also reports broadband dispersion values varying from −800 ps/nm/km to −2600 ps/nm/km over a 200 nm wavelength (1400–1600 nm) range, and kappa values near 300 nm, which matches well with standard single mode fiber. Using the principle of power transfer from the inner core to the outer core after the coupling wavelength, we have investigated possible design of ASE suppressed amplifier in which wavelengths after the coupling wavelength cannot be amplified as most of the power tunnel to the outer core, where doped ion does not exist.

Authors wish to report a major discordance between Xpert MTB/RIF Ultra Trace positivity (GeneXpert, Cepheid) and follow up by liquid culture.

Objective India is a country sharing one fourth of the global incidence of tuberculosis. It is much easier to diagnose pulmonary cases, but challenges are with extrapulmonary cases. Genital tuberculosis is considered as an important cause of infertility in young females in India and difficult to diagnose. It requires incorporation of different modalities that should correctly, timely and rapidly diagnose the case. Methods This study was conducted retrospectively for a period of 12 months on 438 endometrial samples from females with history of infertility. Three modalities namely Ziehl-Neelsen staining, Automated liquid culture and Nucleic acid amplification technique (TB-PCR) were compared and their sensitivity in diagnosis of genital tuberculosis was ascertained. Results Out of 438 samples, 18 samples were found positive with at least one modality. TB-PCR positivity was 3.6% (16 cases) in comparison to culture where positivity was 1.59% (7 cases). Five samples were found culture and TB-PCR positive and only one sample was positive by all three diagnostic tests. Conclusion Infertility in young female per se is usually heart breaking and distressing. Therefore, it is essential to diagnose and treat the cases of genital tuberculosis before irreversible damage of tube may happen. Although, advancement in diagnostic field is there from microscopy to molecular method, but still diagnosis of genital tuberculosis is challenging. Correct diagnosis prevents young female from mental trauma and toxicity of anti-tuberculosis drugs given on suspicion in high prevalence country like India.

Visceral leishmaniasis (VL) is World Health Organization designated most serious leishmaniasis with an annual mortality rate of 50,000. Even after country specific eradication programs, the disease continues to multiply with added complexities like resistance development, drug hypersensitivity and associated infections. Newer therapeutic interventions are urgently warranted to control the spread. Present study aims to arrive at terpenoid andrographolide engineered gold nanoparticle (AGAunps) facile synthesis and its efficacy evaluations against wild and drug resistant VL strains for the first time. Molecular bio-organic conjugation of AGAunp was confirmed in FT-IR and EDAX studies. Nano-gold plasmon response was recorded at 543 nm and the average size in TEM was 14 nm. SAED pattern and XRD observations proved fcc crystalline structure of nano-gold. AGAunp recorded spherical geometry in AFM and TEM. PDI value of 0.137 revealed the monodisperse nature of the nano-scale population. AGAunp exhibited strong antileishmanicidal effect both against wild type (IC

We have performed a detailed analysis of a new design based on chalcogenide material for achieving high mode effective area for application in the IR wavelength. The core of the novel design consists of four rings of hexagonal arrangement of high refractive index rods in the background of low index chalcogenide material. The dependence of effective mode area upon the rod diameter and rod-to-rod distance is investigated in detail. The single mode operation for high power delivery in the IR wavelength has been carried out to insure distortion free operation with normal dispersion and low dispersion slope. Our numerical investigation reports an ultra high effective area ~100,500 µm2 around 5 µm of wavelength with Λ = 40 µm and d = 1.0 µm keeping the operation in the single-mode nature with very low propagation loss. Our design methodology will unleash a new dimension in photonic system with a new type of microstructured core design for both communication and IR applications.

In this paper, a new technique to attain a tunable parametric amplifier for application in the communication wavelength, based on near-zero ultraflat dispersion with PCF, has been explored. The chromatic dispersion profile and the corresponding zero dispersion wavelength (ZDW) of the optimized PCF can be well tuned to provide a wide gain spectrum in the communication wavelength just by changing the temperature of the fiber. A detailed investigation reveals that the fiber retains its near-zero ultraflat nature when the temperature is increased by 2.50 °C from room temperature. While changing the temperature, the ZDWs can be well tuned, giving rise to a gain region of hundreds of nanometers around the pumping wavelength by changing the temperature of the fiber externally.

We report here our experimental studies on efficient excitation of higher-order modes in a few-mode fiber realized through selective chemical etching of single-mode fiber, depositing a dynamic refractive index profile coating (gelatin) and designing a well-performing high relative humidity (RH) (73%-99% RH) sensor with sensitivity as high as ∼1.2 dBm/% RH and fast response (∼125 ms). The design relies on fixing quasi-adiabatic transition of the single-mode-few-mode-single-mode configuration to launch light at angles corresponding to desired higher-order modes, pushing more power into the coating. Our systematic study using the devised hybrid theoretical ray- and wave-optic model uniquely interprets the variety of experimental results.

We devised a tunable cavity fiber Fabry-Perot magnetometer using deflection of cobalt-doped nickel ferrite coated optical fiber cantilever. Sensitivity is improved by introducing a silver coated fiber-mirror in the developed configuration.

An ultra-wide 1646 nm (1084–2730 nm), continuous-wave single pump parametric amplification spanning from near-infrared to short-wave infrared band (NIR-SWIR) in a host lead-silicate based binary multi-clad microstructure fiber (BMMF) is analyzed and reported. This ultra-broad band (widest reported to date) parametric amplification with gain more than 10 dB is theoretically achieved by a combination of low input pump power source ~7 W and a short-length of ~70 cm of nonlinear-BMMF through accurately engineered multi-order dispersion coefficients. A highly efficient theoretical formulation based on four-wave-mixing (FWM) is worked out to determine fiber׳s chromatic dispersion (D) profile which is used to optimise the gain-bandwidth and ripple of the parametric gain profile. It is seen that by appropriately controlling the higher-order dispersion coefficient (up-to sixth order), a great enhancement in the gain-bandwidth (2–3 times) can be achieved when operated very close to zero-dispersion wavelength (ZDW) in the anomalous dispersion regime. Moreover, the proposed theoretical model can predict the maximum realizable spectral width and the required pump-detuning (w.r.t ZDW) of any advanced complex microstructured fiber. Our thorough investigation of the wide variety of broadband gain spectra obtained as an integral part of this research work opens up the way for realizing amplification in the region (SWIR) located far from the pump (NIR) where good amplifiers currently do not exist.

We present a new design study of ultra-flat near zero dispersion PCF with selectively liquid infiltration with all uniform air-holes in the cladding. The dependence of the individual parameters upon dispersion has been presented in detail. The study establishes that varying Λ influences the total dispersion, whereas d has the desired effect of modifying the dispersion slope, and varying nL modifies both. With the above study we could achieve near zero ultra-flat dispersion as small as 0 ± 0.41 ps/nm/km for broad wavelength range of 452 nm. The optimized near zero ultra-flat dispersion PCF has been targeted for smooth and flat broadband spectrum supercontinuum generation (SCG) for near Infrared (IR) applications. Broadband SC generations corresponding to three different designs of ultra-flat dispersion fiber have been carried out by using picoseconds pulse laser around the first zero dispersion wavelengths (ZDW). The numerical results show that FWHM of around 400 nm with less than a meter long fiber can be achieved with these fibers that cover most of the communication wavelength bands. The proposed design study will be applicable for applications in the field of tomography, Dense Wavelength Division Multiplexing (DWDM) system, spectroscopy, etc.

A systematic analysis of the dispersion characteristics of a selectively liquid-filled dual-core PCF by varying different geometrical parameters towards achieving ultra negative dispersion values around a desired wavelength has been carried out. The dependence of PCF parameters along with the infiltrating liquid upon dispersion has been investigated. Our analysis establishes that with the increase of Λ , the total dispersion is red-shifted with a reduction of the negative dispersion. Again, the dispersion is red-shifted but with an increment of negative dispersion and narrower FWHM for an increase of d . In contrary to the above dependence of Λ and d , with an increase of n L , the dispersion gets blue-shifted with an increase of negative dispersion at the cost of reduced FWHM. Our numerical study establishes a high negative dispersion of −52,100 ps/nm/km around 1550 nm through an optimized design. Three such designs of selectively liquid filled dual-core PCF demonstrating a negative dispersion from −28,700 ps/nm/km to −52,100 ps/nm/km around the wavelength of 1550 nm with available practical liquids have been presented to demonstrate the effectiveness of the method. Our optimized structures demonstrate excellent tunable properties with temperatures for various optical communication systems based devices. Our proposed PCF will be an excellent candidate for dispersion compensation in long-haul data transmission as being thousand times more than the available DCFs. Our approach of dispersion engineering will be helpful for dispersion engineering related applications like true time delay instruments, Raman amplifier, ASE suppression, Four-wave mixing etc.

A new design of all-normal and near zero flattened dispersion based on all-silica photonic crystal fibers (PCFs) using selectively liquid infiltration technique has been proposed to realize smooth broadband supercontinuum generation (SCG). The investigation gives the details of the effect of different geometrical parameters along with the infiltrating liquids on the dispersion characteristics of the fiber. Numerical investigations establish a dispersion value of −0.48 ps/nm/km around the wavelength of 1.55 μm. The optimized design has been found to be suitable for SCG around the C band of wavelength with flat broadband wavelength band (375 nm bandwidth) and smooth spectrum with only a meter long of the PCF. The proposed structure also demonstrates good tunable properties that can help correct possible fabrication mismatch towards a better optimization design for various optical communication systems.

Background: Serological diagnosis of dengue fever is based on the detection of NS1 antigen and further confirmed by the assay of dengue IgM and IgG. Rapid Diagnostic Tests (RDTs) are no longer recommended for use by the Government of India. However, there is a requirement of rapid results without compromising on the test quality. Accordingly, we undertook an evaluation of a novel cartridge-based system employing a unique table-top diagnostic device for dengue NS1 antigen by BluSense Diagnostics incorporating a patented Immuno-Magnetic Assay (IMA).Methods: A total of 309 samples were tested on unlinked anonymous basis. Each sample was tested using NS1 Ag ELISA (Microlisa, J. Mitra), ViroTrack and NS1 RDT (SD Alere) and results were recorded. Discordant samples were further tested by dengue NS1 AG ELISA (Panbio) and dengue IgG/IgM Maclisa (J. Mitra).Results: When compared with approved ELISA kits used globally the Virotrack test returned a sensitivity of 94.74%; specificity of 97.44%; PPV of 97.30%; NPV of 95% and accuracy of 96.10%. Hourly throughput is 5-6 samples.Conclusions: The Virotrack system is highly suitable as a POCT module in HCFs with low to moderate workload that employs novel technology, is rapid, user friendly and comparable to the ELISA in sensitivity and specificity. The equipment is user friendly and can work both on plasma/serum and whole blood. Model with multiple modules (3-4) will improve the throughput and turnaround time. Evaluation of this novel technology has been done in India for the first time.

Human paragonimiasis is caused by the Paragonimus species of lung flukes. These are widely distributed worldwide including East and Southeast Asia. The first ever case of paragonimiasis was reported by Kerbert from the lungs of a Bengal tiger more than a century ago.1 In India the first case was reported from Manipur in 1982. Subsequently, endemic foci of Paragonimus westermani and Paragonimus heterotremus have been reported from Manipur, Nagaland, Arunachal Pradesh, Bengal and Assam.1,2 Human infection primarily results from consumption of raw or undercooked, pickled, brine soaked crabs, crayfish and shrimps harboring the infective form.3 Paragonimiasis in India often mimics pulmonary tuberculosis.4,5

Invasive pulmonary mucormycosis is an unusual but an emerging cause of fatal massive hemoptysis. The commoner causes of massive hemoptysis are pulmonary tuberculosis, bronchiectasis and lung carcinoma. Pulmonary mucormycosis, unlike rhinocerebral mucormycosis has been reported infrequently. Co-morbidity such as uncontrolled diabetes mellitus is an important predisposing factor for acute fulminant mucormycosis. Herein we report a case of fatal massive hemoptysis caused due to mucormycosis in a young male patient.

Detailed numerical analysis for dispersion properties and losses has been carried out for a new type of Photonic crystal fiber where the air-holes are arranged in a circular pattern with a silica matrix called as Circular Photonic Crystal Fiber (C-PCF). The dependence of different PCF geometrical parameters namely different circular spacings, air-hole diameter and numbers of air-hole rings are carried out in detail towards practical applications. Our numerical analysis establishes that total dispersion is strongly affected by the interplay between material dispersion and waveguide dispersion. For smaller air-filing fraction, adding extra air-hole rings does not change dispersion much whereas for higher air-filling fraction, the dispersion nature changes significantly. With proper adjustment of the parameters ultra-flattened dispersion could be achieved; though the application can be limited by higher losses. However, the ultra-flat dispersion fibers can be used for practical high power applications like supercontinuum generation (SCG) by reducing the loss at the pumping wavelength by increasing the no of air-hole rings. Broadband smooth SCG can also be achieved with low loss oscillating near-zero dispersion fiber with higher no of air-hole rings. The detail study shows that for realistic dispersion engineering we need to be careful for both loss and dispersion.

A detailed study is presented on the lasing properties of an erbium-doped photonic crystal fiber (PCF) laser. The effects of the host PCF’s structure and laser parameters on continuous-wave laser emission are analyzed by considering the confinement and overlap of pump and signal fields in the gain medium for varying values of pitch, hole diameter, and doping radius. For analysis, we used a finite-difference mode-calculation algorithm devised with standard population and propagation rate-equation solver. Our analysis, applied to an experimentally realized PCF laser, reproduces the observed/reported data, thereby showing the efficacy of our analysis. Finally, a fiber geometry to realize a laser with threshold as low as 6 mW using a short fiber length of 0.52 m is prescribed. The aim of the design is to greatly reduce splice loss with standard single-mode SM28/G.652 fiber while maintaining the optimum performance. These results are new in PCF laser research and should be useful in realizing high performance ...

This article reports a new air-silica photonic crystal fiber structure of high birefringence (~10−2). The birefringence is due to large axial anisotropy introduced in the fiber geometry by a preferred arrangement of circular air holes of different sizes in the cladding structure along orthogonal directions. A series study of birefringence and cut-off properties of the fiber that leads to optimization of geometrical parameters toward maximized birefringence achievable in the single-mode regime through this micro-structure is provided. Also, other inherently related modal properties of the fiber and the stack design toward preform realization are investigated. The findings should be useful in realizing high-performance high-birefringence fiber.

We report here the results of our studies on dynamic refractive-index (RI) profile few-layer fibers in view of controlling the mode-field profile, in particular the evanescent tails under varying structural configuration. We experimentally fabricate dynamic RI profile few-layer fibers using thin gelatin coating on selectively etched fibers and illustrate how the excitation of various modes and the evanescent field at the interface can be controlled with changing humidity parameter. As a technology outcome of this research, we demonstrate through an optimized structural configuration a well performing fiber-optic high (70%-98%) relative humidity (RH) sensor with sensitivity as high as -1.07 dBm/%RH.