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The freshwater rockpools support high endemic biodiversity but are poorly studied habitats in the Western Ghats biodiversity hotspot. These freshwater rock pools are situated on outcrops at various elevations in the Western Ghats and are composed of different bedrocks such as laterite and basalt. We aimed to analyze the water quality, geographical position based differences in the water chemistry and the role of bedrock in determining the water chemistry of the rock pools. Our study showed a wide range of water quality variables such as pH, conductivity, and ionic contents that attributed to the natural variation. We observed a drastic variation in the anions and cations at low elevation pools. Rock type and precipitation are influencing the ionic concentration; for example, Calcium and Bromide could be attributed to the seasonal precipitation and geomorphology. This documentation of physicochemical properties of the Western Ghats rock pools can form a baseline for further detailed studies.

Introduction: Adrenal gland tumors are rare. Asymptomatic adrenal tumours are found in 2-10% of the population worldwide, out of which, adrenocortical carcinomas(ACC) have an incidence of 0.5-2 cases/million population/year. ACC accounts for 0.05% -0.2% of all malignancies with a bimodal age distribution, in the first two decades and then in the fifth decade. They can be asymptomatic and diagnosed as Incidentalomas or present with signs and symptoms of hormone imbalance. Materials and methods: In this 2 year hospital-based retrospective case series from June,2018 to May,2020 , 5 cases of adrenal gland tumors diagnosed in the Department of Pathology , GMCH, were retrieved from the archives and reviewed. Each case was analyzed with respect to age , sex, site and tumor characteristics. Results: In this 2-year period, 5 cases of adrenal tumors were found. The age range of the patients was 8-54 years. Out of 5 cases,2 cases were male and 3 cases were female. Out of 5 cases of , 4 were on the left side and 1 was on the right side.2 out of the 5 cases were diagnosed as Adrenocortical carcinoma(low grade), 1 as Phaeochromocytoma and 2 as Adrenocortical Adenoma. Conclusion: Adrenal gland tumors are rare, so the pathologic classification and determination of prognosis are very challenging.

A new triundulate naviculoid diatom genus is described from the Western Ghats of Peninsular India and Hainan Province, China. The new taxon, Kulikovskiyia gen. nov. has robust conical spines along its margin and at the apices and the external valve face has longitudinally‐oriented siliceous slat system extending the length of the valve. The external distal raphe ends bifurcate and terminates on the valve face. There appear to be superficial similarities between this Asian genus and species and Playaensis, a genus comprised of two species found only in the western USA. The systematic position of Kulikovskiyia is discussed, and other than noting its similarities to other biraphid naviculoid diatoms due to symmetry features and the position of the raphe, we are uncertain about its systematic placement at finer levels of classification.

Objective: The objective of the study was to explore the color intensity and antioxidative capacity of mango honey available from local niches, in and around Malda, West Bengal, India. Methods: Four mango honey samples: LMH1, LMH2, LMH3, and LMH4, were collected from bee hives, in and around Malda, India, and were subjected to determine the color intensity and antioxidative capacity in 2, 2-diphenyl-1-picrylhydrazyl system. Results: The honey samples tested had light to dark color variation with color intensity values of 583.59–1842.84 mAU. The total phenolic content (TPC) of the honey samples ranged from 434.52 to 1450.74 μg gallic acid equivalents/ml, while the total flavonoids content (TFC) ranged 39.4–72.67 mg quercetin equivalents/100 g of honey. The honey samples displayed antioxidative activity (AOA) with 9.91–76% inhibition capacity, and the IC50 values of 8.37–19.38 mg/ml. The color intensity of test honeys displayed positive correlation with the TPC (r=0.907) and TFC (r=0.863), while negative correlation between honey color intensity and IC50 values (r=−0.955) was recorded. Conclusion: The locally available mango honeys were rich in bioactive components displaying excellent AOA, and thus, the native honey might be utilized as the potential source of natural antioxidant in our part of the globe.

Germainiella chandranii sp. nov. is described from a Myristica swamp of the Western Ghats, India, on the basis of light and scanning electron microscopy. The new species resembles two related gener...

Two new diatom taxa belonging to the genus Stauroneis Ehrenberg were discovered from an aerophilic habitat in Sikkim, India, a part of the Eastern Himalayas. The morphology of Stauroneis sikkimensi...

Composites design has always been perceived to be complicated, time-consuming and therefore not affordable. With a paradigm shift, it is possible to make composites are as straightforward as metals. Each metal is characterized by two key material properties: its Young’s modulus and strength. The adoption of the Tsai’s modulus as the only stiffness constant characterising any CFRP, and failure strain as the only measure of strength, we can make composite design as straightforward as metals design. Actually, with these two material characteristics, for any CFRP, material, laminate, and strain allowable can all be scaled, just like metals. Another break-through is the replacement of the traditional quad laminates of 0, ±45, 90 by double-double (DD) in [±Φ/±ψ]. This replacement allows to substuture a discrete collection by a continuous field of orientations. A few dozen choices, replaced by hundreds. Indeed, double-double can make structures lighter that quad cannot do, thanks to the Lam-search optimizer, which is able, in combination with Fem tools, to sort, instantaneously, the best DD angles allowing laminates stiffness and strength tailored on specific loading conditions. The bottom line: Tsai’s modulus and double-double are new but are simple conceptually, and Lam-search makes their use practical. In the end, lower weight and lower cost are derived by DD to deliver aggressive taper and 1-axis layup that will be stiff, strong, easy to layup, not prone to error, wrinkle, warpage and delaminatnion.

This communication stands for the phytochemical analysis, and antibacterial activity ofEnhydra fluctuans, alone and in combination with some antibiotics, against gram-negative and gram-positive bacteria. Following disc diffusion, the methanolic extract ofE. fluctuans(MEE) had antibacterial activity against gram-positive (B. cereusandL. monocytogenes) and gram-negative (A. baumanniiandP. aeruginosa) clinical as well as standard (E. coliATCC 25922 andL. monocytogenesMTCC 657) bacterial strains, displaying ZDI (zone of the diameter of inhibition) values 12 – 24 mm. The aqueous extract ofE. fluctuans(AEE) showed no activity againstP. aeruginosa; however, for the other test bacterial isolates AEE had ZDIs of 13 – 21 mm (for gram-negative bacteria) and 10 – 17 mm (for gram-positive bacteria). The MIC (minimum inhibitory concentration) values of MEE, for both gram-negative and gram-positive bacteria, ranged from 2.5 to 10 mg/ml, by agar dilution method. The extracts (AEE and MEE) were screened qualitatively to contain bioactive components: flavonoids, glycosides, steroids, terpenoids, phenols, quinone and saponins, while cardiac glycoside was detected in AEE only. The HPLC chromatogram showed the presence of 14 detectable compounds, within the retention time of 1.53 - 5.69 min, in MEE. The growth inhibitory indices of 0.59 – 1.08, from the antibiotic-MEE combined action, demonstrated synergism against the test bacterial strains. TheE. fluctuans, alone or in combination with antibiotics, might be useful in combating infections caused by both gram-negative and gram-positive bacteria.

Aims: To assess the antioxidant and antibacterial activities of two locally available natural honey samples, and determine the total phenolic content (TPC) of the honeys.Methods: Antibacterial activity of two local natural honey samples (citrus honey: LNH1 and mango honey: LNH2) was determined against the clinical bacterial isolates of Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella enterica serovar Typhi, and Escherichia coli ATCC 25922 strain, by agar-well diffusion method. The antioxidative activity of the honey samples (LNH1 and LNH2) was determined in DPPH system, and the IC50 values were calculated. The bioactive components present in the test honey samples were assessed qualitatively, and the TPC was quantified.Results: The honey samples showed the presence of different bioactive components (flavonoids, steroids, phenol, terpenoids and quinone); the TPCs were estimated in LNH1 and LNH2 were 195.5 μg/ml and 333 μg/ml, respectively. In DPPH system, the scavenging activities of LNH1 and LNH2 ranged 43.46–75.18% and 36.09–77. 23%, respectively, with respective IC50 values of 3.83 mg/ml and 6.75 mg/ml. The test honey samples showed antibacterial activity both against gram-positive (Staph. aureus) and gram-negative (Ps. aeruginosa and S. enterica serovar Typhi) bacterial pathogens, and against the E. coli ATCC 25922 strain.Conclusion: The locally available natural honey may be used as rich source of antioxidant and can be used as effective antibacterial agent in order to combat the bacterial infection to humans.

For the past six years, we have been benefiting from the discovery by Tsai and Melo (2014) that the trace of the plane stress stiffness matrix ( tr ( Q ) ) of an orthotropic composite is a fundamental and powerful scaling property of laminated composite materials. Algebraically, tr ( Q ) turns out to be a measure of the summation of the moduli of the material. It is, therefore, a material property. Additionally, since tr ( Q ) is an invariant of the stiffness tensor Q , independently of the coordinate system, the number of layers, layup sequence and loading condition (in-plane or flexural) in a laminate, if the material system remains the same, tr ( Q ) = tr ( A ∗ ) = tr ( D ∗ ) is still the same. Therefore, tr ( Q ) is the total stiffness that one can work with making it one of the most powerful and fundamental concepts discovered in the theory of composites recently. By reducing the number of variables, this concept shall simplify the design, analysis and optimization of composite laminates, thus enabling lighter, stronger and better parts. The reduced number of variables shall result in reducing the number and type of tests required for characterization of composite laminates, thus reducing bureaucratic certification burden. These effects shall enable a new era in the progress of composites in the future. For the above-mentioned reasons, it is proposed here to call this fundamental property, tr ( Q ) , as Tsai’s Modulus.

One of the widely used matrices for manufacturing high service-temperature composites are Bismaleimides (BMI). Due to its superior mechanical properties such as high temperature strength, it has been used widely in aerospace applications. In this research paper, the effects of cure and post-cure parameters on the mechanical property of Out-Of-Autoclave (OOA) fabricated composites were investigated by the aid of Design of Experiments (DOE) techniques. Short Beam Shear (SBS) test and ultrasonic guided waves were used to characterize the laminate properties under different curing settings. A mathematical model was developed relating the SBS strength to cure and post-cure conditions. Response Surface Methodology was unitized to achieve the optimized curing settings. The Ultrasound based non-destructive material characterization was employed to verify the effects of curing conditions on material strength. It was also concluded that the optimized mechanical strength depended on both curing and post-curing conditions and could not be optimized independently.

In this paper, an investigation is carried out to understand the influence of applied bending loads on ultrasonic guided-waves propagating in laminated composite structures. Composite coupons fabricated from unidirectional plies are instrumented with piezoelectric transducers, and subjected to three point bending test. Load effects on sensing signal parameters such as signal amplitude and phase are studied for wave propagation paths along the fiber direction, as well as paths that are transverse to the fiber direction. Load compensation strategy for addressing load influence on signal amplitude is proposed.

This paper describes research toward developing prognostics technologies for light water nuclear power reactor components. The focus of this paper is on passive components (those that do not need t...

Despite more than 150 years of diatom research in India, cymbelloid taxa have rarely been investigated when compared to the other parts of the world. A new freshwater species of Encyonema Kutzing was discovered from the mountain ranges of Peninsular India and is described based on light and scanning electron microscopy observations. This paper provides a comparison of the new taxa with morphologically similar taxa of the genus Encyonema. Encyonema keshrii, sp. nov., is characterized on the basis of distinctive morphological characters including valve and apex shape as well as striae density. Enccyonema keshrii, sp. nov., is found to be a wide spread taxon with distribution across the Eastern Ghats, Western Ghats and the Eastern Himalayas of Indian subcontinent.

The monitoring and subsequent management of structural health plays an essential role in composite materials and structures. Structural health monitoring (SHM) is an emerging technology which combines advanced sensor technologies with intelligent algorithms to interrogate the “health” condition of structures in real time or whenever necessary. Benefits of the SHM technology include improvement of reliability and safety, enhancement of performance and operation, potential for automated unsupervised monitoring, and reduction of life-cycle cost. Recent advancements in SHM technology have resulted in significant and promising techniques offering autonomous solutions for detecting and assessing the health condition of composite structures, providing a real-time early warning capability to mitigate damage, and reducing considerably downtime and maintenance costs. SHM technology can be applied to a wide range of systems within the aerospace, mechanical and civil engineering communities. This chapter examines the recent state-of-the-art SHM sensing, diagnostic and computational approaches for composite structures and the requirements for such applications.

Accurate interpretation of in-situ piezoelectric sensor signals is a challenging task. This paper presents the development of a numerical compensation model based on physical insight to address the influence of structural loads on piezo-sensor signals. The model requires knowledge of in-situ strain and temperature distribution in a structure while acquiring piezoelectric sensor signals. The parameters of the numerical model are obtained using experiments on flat aluminum plate under uniaxial tensile loading. It is shown that the model parameters obtained experimentally can be used for different structures, and sensor layout. Furthermore, the combined effects of load and temperature on the piezo-sensor response are also investigated and it is observed that both of these factors have a coupled effect on the sensor signals. It is proposed to obtain compensation model parameters under a range of operating temperatures to address this coupling effect. An important outcome of this study is a new load monitoring concept using in-situ piezoelectric sensor signals to track changes in the load paths in a structure.

Ultrasound has long been known to be capable of measuring water level. Zero-degree ultrasound transducers may be used to send an L-wave through the fluid and receive a reflected signal from the fluid/gas interface surface. The level of the fluid is proportional to the sound wave time of flight to traverse the water path. This approach may even be used from outside the fluid containment wall by sending the wave through the tank or pipe bottom. The approach, however, does not work well if there is only a thin layer of fluid consisting of one or two millimeters or even only a few droplets. Surface waves are also known to be sensitive to the presence or absence of fluid on a surface. A surface wave may be transmitted a significant distance by a transmitting transducer and then received by a similar transducer. If the surface along the wave path is wet with even a few droplets of fluid, the surface wave may be significantly attenuated. Generating and measuring such a surface wave from the opposite side of a ta...

Significant progress has recently been achieved in structural health monitoring, maturing the technology through quantification, validation, and verification to promote implementation and fielding of SHM. In addition, there is ongoing work seeking to detect damage precursors and to deploy structural health monitoring systems over large areas, moving the technology beyond hot-spot monitoring to global state sensing for full structural coverage. A large number of small sensors of multiple types are necessary in order to accomplish the goals of structural health monitoring, enabling increased sensing capabilities while reducing parasitic effects on host structures. Conventional sensors are large and heavy, adding to the weight of a structure and requiring physical accommodation without adding to and potentially degrading the strength of the overall structure. Increased numbers of sensors must also be deployed to span large areas while maintaining or increasing sensing resolution and capabilities. Traditionally, these sensors are assembled, wired, and installed individually, by hand, making mass deployment prohibitively time consuming and expensive. In order to overcome these limitations, the Structures and Composites Lab at Stanford University has worked to develop bio-inspired microfabricated stretchable sensor networks. Adopting the techniques of complementary metal-oxide semiconductor and microelectromechanical system fabrication, new methods are being developed to create integrated networks of large numbers of various micro-scale sensors, processors, switches, and all wiring in a single fabrication process. Then the networks are stretched to span areas orders of magnitude larger than the original fabrication area and deployed onto host structures. The small-scale components enable interlaminar installation in laminar composites or adhesive layers of built-up structures while simultaneously minimizing parasitic effects on the host structure. Additionally, data processing and interpretation capabilities could be embedded into the network before material integration to make the material truly multifunctional and intelligent once fully deployed. This article reviews the current accomplishments and future vision for these systems in the pursuit of state sensing and intelligent materials for self-diagnostics and health monitoring.

This article investigates the role of ambient temperature in causing changes to the structural wave propagation, as sensed by piezoelectric transducers, in a newer perspective. A novel approach is proposed to compensate the influence of temperature on piezo-sensor response using both analytical models and numerical simulations. Parametric studies using numerical simulations for plates with surface-mounted piezoelectric transducers establish linear functional relationship between change in sensor signals and specific combination of material properties, within certain temperature range. A numerical temperature compensation model is developed based on this functional relationship to reconstruct piezo-sensor signals at elevated temperatures. Matching pursuit–based signal analysis and reconstruction schemes are used in this study. Practical efficacy of the compensation model is tested for metallic structures with both simple and complex geometries. Model-based reconstruction of first wave packets in the sensor signals is found to match quite well with the experimental measurements. Performance of the proposed compensation model is also found to be at par with the existing state-of-art temperature compensation methods. A very limited set of baseline sensor data is required to estimate unknown model parameters, making this approach to be efficient and practically useful. The output of the compensation model is also used to obtain an accurate estimate of damage location in a structure under varying ambient temperature environments.

Ninastrelnikovia lateritica sp. nov., a new and rare freshwater biraphid diatom species was discovered from a rocky ephemeral pool of the Kaas plateau, Western Ghats, and described on the basis of light and scanning electron microscopy observations. A morphological comparison with the two other described Ninastrelnikovia taxa is provided. This new species can easily be separated from its congeners by the shape of the valve apex and absence of any second inflation along the valve margin, as well as the shape and structure of the external distal raphe ends and internal proximal raphe ends. The members of Ninastrelnikovia are characterized by two morphological types of valves. Valves on the ends of colonies exhibit one set of morphological features while valves located in the middle of colonies show another set of morphological features. Morphological details of the valves are discussed.

Diatoms were collected from the Kotulpur area of West Bengal. Four diatom taxa, namely,Eunotia minor(Kützing) Grunow,Achnanthidium minutissimum(Kützing) Czarnecki,Lemnicola hungarica(Grunow) Round and Basson, andNavicula radiosaKützing were observed using scanning electron microscopy (SEM) and identified in light of modern diatom taxonomic trends. ExceptEunotia minor, all these taxa are new records to Eastern India. A note on the taxonomy ofAchnanthes pseudobiasolletianaas described by Gandhi andEunotia serratavar.diadema(Ehr.) R. M. Patrick as reported by Dwivedi and Misra has been added.

The present communication dealt with 20 taxa belongs to 14 genera of fresh water diatoms from different aquatic habitats of Joypur forest of Bankura district, West bengal.

This paper presents recent progress towards developing a prognostic health management framework for passive components of advanced reactors (AR). The focus of this paper is on lifecycle prognostics for passive components using a Bayesian prognostic algorithm that provides a natural framework for incorporating different sources of variability and uncertainties inherent in the operations of AR. High-temperature creep damage, a prototypic failure mechanism in AR materials, is used as the context for this research. A Bayesian model selection approach is implemented to select the appropriate creep degradation model at any given time, using relevant sensor measurements reflecting the material degradation state. The model selection approach, based on reversible jump Markov chain Monte Carlo methods, is integrated with Bayesian particle filter-based prognostic framework. The proposed approach is evaluated using strain measurements obtained from accelerated creep testing of stainless steel specimens. Results indicate feasibility of the proposed approach in accurately identifying the creep degradation stage from the available measurements at a given time. Effect of uncertainties in material degradation model and measurement noise on the performance of the prognostic algorithm is also investigated.

This paper concerns a reflection on a new decision boundary technique devoted for baseline-free damage detection purpose. Its scope focuses in studying analytically the impact of an unknown disturbance on the behavior of a monitored structure, through linear and nonlinear perturbation models. These perturbation models are introduced to interpret how an unknown disturbance away linearly and nonlinearly a monitored structure from its initial state, which is a healthy one, to its current state, which can be damaged or a healthy one that has undergone environmental/operational variations. To quantify the amount of that unknown disturbance effect, matrix perturbation theory is addressed to define two analytical bounds. The gap between them gives the decision regarding the monitored structure current state. The effectiveness of the proposed approach is demonstrated through an experimental setup of a test coupon aluminum plate, which has undergone varying loads and temperatures conditions, and crack damage cases. doi: 10.12783/SHM2015/367

Various 4,4-diphenylmethane diisocyanate (MDI) based polyurethane adhesives have been developed using polyethylene glycols (PEG) of different molecular weights. The formulations were modified using different blocking agents to inhibit the isocyanate-moisture reaction. Composites of poly(methyl methacrylate) sheets were developed in which these adhesives gave transparent films and their shattering characteristics were tested in a bullet firing machine developed here. The damaged area was measured and used to characterize the adhesive strength. The molecular weight of the soft segment (diol) and the nature of the blocking agent both were found to affect drastically the urethane film properties.

Background: Orphans are the special group of children who are generally deprived and prone to develop psychiatric disorders even reared in well run institution. Objectives: To find out the prevalence of the behavioral and emotional disorder among the children living in orphanage in Dhaka city, and to assess the possible factors associated with the presence of disorders among this study population. Methods: It was a cross sectional descriptive study conducted in selected orphanages. A Total 342 cases were included. One stage structured assessment of psychopathology was carried out by using a valid Bangla version of DAWBA (The Development and Well-Being Assessment). Data analysis was done by SPSS for windows 16.0 version. Results: The results indicate that overall prevalence of behavioral and emotional disorders were 40.35%, in which Behavioral disorder was 26.9%, Emotional disorder was 10.2% and both Behavioral and Emotional disorder were 3.2%. Higher length of stay and low level of education of foster mother were significantly associated with psychiatric morbidity of the respondents. Conclusions: It can be concluded that behavioral and emotional disorders are highly prevalent among orphan children and adolescents with residential care that needs to be addressed. Moreover, measure for early identification and intervention will improve the quality of life of the orphan population. DOI: http://dx.doi.org/10.3329/bsmmuj.v5i1.10997 BSMMU J 2012; 5(1):29-34

A critical part of structural health monitoring is accurate detection of damages in the structure. This paper presents the results of two multi-class damage detection and identification approaches based on classification using Support Vector Machine (SVM) and Artificial Neural Networks (ANN). The article under test was a fiber composite panel modeled by a Finite Element Model (FEM). Static strain data were acquired at 6 predefined locations and mixed with Gaussian noise to simulate performance of real strain sensors. Strain data were then normalized by the mean of the strain values. Two experiments were performed for the performance evaluation of damage detection and identification. In both experiments, one healthy structure and two damaged structures with one and two small cracks were simulated with varying material properties and loading conditions (45 cases for each structure). The SVM and ANN models were trained with 70% of these samples and the remaining 30% samples were used for validation. The objective of the first experiment was to detect whether or not the panel was damaged. In this two class problem the average damage detection accuracy for ANN and SVM were 93.2% and 96.66% respectively. The objective of second experiment was to detect the severity of the damage by differentiating between structures with one crack and two cracks. In this three class problem the average prediction accuracy for ANN and SVM were 83.5% and 90.05% respectively. These results suggest that for noisy data, SVM may perform better than ANN for this problem.

Reliable damage detection is crucial for assessing the integrity of a structure. In this paper, a numerical study of a composite panel fabricated to simulate a crack is undertaken using finite element methods (FEM). The damage to be considered is a transverse crack which pre-exists in the structure. The finite element models are developed for an undamaged and a damaged composite panel to compute the change in Lamb wave response due to the existence of a crack. The model is validated using shear lag analysis applied at the crack. The results are verified experimentally by comparing the results for an undamaged composite panel and a composite panel fabricated with a simulated crack using the vacuum assisted resin transfer molding (VARTM) process. The responses for each panel are obtained using surface mounted lead zirconate titanate (PZT) actuators and sensors. PZT is used to generate Lamb waves which produce stress throughout the panel thickness. Propagation characteristics of Lamb waves are varied by the presence of damage. The sensor data provide reliable information about the integrity of the structure. Numerical results are compared to the sensor output to ensure accuracy of the damage detection system.

This contribution presents a novel strategy to achieve real-time prediction of non-penetrating impact-induced damage, especially delamination between plies of composite laminated structures. The proposed strategy aims to create an optimum-sized database of simulated damage information on a given laminated structure using numerical failure models and pattern recognition technique. A multi-stage data clustering algorithm is implemented to identify regions in the structural Finite Element (FE) model that have similar damage signatures. The generated database is linked to the real-time estimate of impact location and load-time history obtained from piezoelectric transducers based passive impact monitoring system. A composite stiffener panel is selected as a model problem and it is shown that the proposed strategy based on pattern recognition will result in large savings in computational cost for the database generation besides providing real-time damage diagnostic capabilities for in-service adverse impact events within certain confidence bounds.

This paper presents a novel model-assisted integrated diagnostics for structural health monitoring. Acousto-ultrasonic Lamb waves are propagated through a structure induced and sensed by an active piezoelectric sensor network. The damage is detected by comparing current sensor signals (with damage) with baseline signals (without damage). Diagnostic algorithm interprets changes in the signals to detect and localize damage. Typically the accuracy of damage localization depends on a priori knowledge of the velocity of Lamb waves. The estimation of Lamb wave velocity for complex structures is very challenging since analytical relations only exist for structures with simple geometries. Hence, a numerical tool based on spectral element method has been developed and employed to simulate acousto-ultrasonic wave propagation in structures. This tool generates an accurate velocity profile of Lamb waves propagating through a complex structure, which is used for offline training of the diagnostic algorithm. In order to achieve accurate diagnostics in varying temperature environments, the diagnostic algorithm has been integrated with a model to compensate for the effect of change in ambient temperature on sensor signals. Numerical tests are carried out to determine the performance of the integrated diagnostics for an aluminum stiffened panel with an open crack at different ambient temperatures. The results demonstrate that the proposed model-assisted integrated diagnostics has the capability of providing an accurate localization of damage in complex structures.

High-temperature polymer-matrix composites (PMCs) are necessary and critical for the development of supersonic aircraft and orbital re-entry vehicles because of the need for light-weight design, high strength-to-weight ratios and high thermal stability in structures. Damage detection is a primary concern in composite structures because they are prone to multiple damage forms that can be hidden within the structure. Damage can include matrix cracking, fiber breakage, and delamination which can be caused by impacts, fatigue, or overloading. To overcome these shortfalls highly damage tolerant structures are employed to improve the safety of structures. Unfortunately this requires additional, potentially unnecessary, structural weight which is detrimental to aerospace structures. Acoustic ultrasound based structural health monitoring (SHM) has demonstrated the ability to overcome these problems by using arrays of Lead Zirconate Titanate piezoelectric transducers typically mounted on a flex circuit all of which is permanently affixed to, or embedded within, a structure [1] [2] [3] [4]. These transducers can excite and detect ultrasonic wave propagation in the structure and diagnostic algorithms, interpreting the signals, have been developed enabling real time inspection for damage. However, modern SHM systems are not capable of surviving the high temperatures experienced in the fabrication and service of High-temperature polymer matrix composites. In particular the Lead Zirconate Titanate piezoelectric elements typically depolarize and lose their functionality at around 200°C [5] [6]. Additionally, current SHM diagnostic algorithms are dependent on baseline data to compare signals to. These signals change with temperature and even just a few degree change can be detrimental to the system’s abilities. The current method for enabling functionality over a range of temperatures is to take numerous sets of baseline data at very high resolution across a range of temperatures. In order to adapt SHM for high temperature composites new piezoelectric materials must be developed capable of surviving elevated fabrication and operational temperatures. Small scale network components must be integrated to reduce detrimental effects of embedding SHM systems within the composite layup [7] [8] [9]. Additionally, methods for reducing the number of baseline data sets in the diagnostic algorithms must be developed. This paper presents development and testing of Bismuth Scandium Lead Titanate piezo ceramic transducers for high temperature SHM. These transducers are incorporated into a stretchable network system and mounted on a glass backing. Functionality is tested using a commercially available data acquisition system designed for SHM and intended for use with PZT transducers. Ongoing development of temperature compensation algorithms is also presented herein.

Next generation technology of integrated health management systems for air-transportation structures will utilize SHM methods in combination with simulation techniques for the prediction of structural degradation induced by adverse events such as impacts. The contribution focuses on the development of an advanced real-time monitoring system for impact loads using passive sensing networks. Starting from the fundamental approach of real-time monitoring based on system identification models, problems of model order, signal conditioning and efficient model training will be addressed. Finally, the load monitoring system is interactively linked to a damage prediction module based on numerical failure analysis employing composite failure criteria. The utilization of appropriate database techniques allows a real-time prediction of impact induced damage after detection of any adverse impact event making information available on developing degradation at the earliest possible state.

Post Kala-azar Dermal Leishmaniasis (PKDL) is a chronic but not life-threatening disease; patients generally do not demand treatment, deserve much more attention because PKDL is highly relevant in the context of Visceral Leishmaniasis (VL) elimination. There is no standard guideline for diagnosis and treatment for PKDL. A species-specific PCR on slit skin smear demonstrated a sensitivity of 93.8%, but it has not been applied for routine diagnostic purpose. The study was conducted to determine the actual disease burden in an endemic area of Malda district, West Bengal, comparison of the three diagnostic tools for PKDL case detection and pattern of lesion regression after treatment. The prevalence of PKDL was determined by active surveillance and confirmed by PCR based diagnosis. Patients were treated with either sodium stibogluconate (SSG) or oral miltefosine and followed up for two years to observe lesion regression period. Twenty six PKDL cases were detected with a prevalence rate of 27.5% among the antileishmanial antibody positive cases. Among three diagnostic methods used, PCR is highly sensitive (88.46%) for case confirmation. In majority of the cases skin lesions persisted after treatment completion which gradually disappeared during 6–12 months post treatment period. Reappearance of lesions noted in two cases after 1.5 years of miltefosine treatment. A significant number of PKDL patients would remain undiagnosed without active mass surveys. Such surveys are required in other endemic areas to attain the ultimate goal of eliminating Kala-azar. PCR-based method is helpful in confirming diagnosis of PKDL, referral laboratory at district or state level can achieve it. So a well-designed study with higher number of samples is essential to establish when/whether PKDL patients are free from parasite after treatment and to determine which PKDL patients need treatment for longer period., Author Summary A significant number of PKDL patients have been detected in the endemic areas of Malda who would remain undiagnosed without active mass surveys. Such active survey is required in other endemic areas of the country to attain the ultimate goal of eliminating Kala-azar from this part of the world by reducing the source of infection. PCR-based method is helpful in confirming diagnosis of PKDL, which is not applicable at field level. A referral laboratory at district or state level can be a solution to the problem. Since PKDL cases do not have a fatal outcome, treatment administration of these cases can be deferred until confirmed results are obtained, which requires about 7 days’ time. The detection of leishmanial DNA in skin lesions during successive treatment courses is essential to establish whether/ when PKDL patients are parasite free during/after treatment and to determine which PKDL patients need treatment for a longer period.

Background: Fine needle aspiration cytology (FNAC) of the thyroid gland has been widely and successfully utilized for diagnosis. Aim: Our aim was to demonstrate the effectiveness of this cheap and simple procedure for the diagnosis of different thyroid lesions, particularly, differentiation of malignant and nonmalignant lesions. In addition, we sought to highlight probable causes of error and possible remedies in the cases showing lack of correlation between cytological and histological diagnoses. Materials and Methods: A total of 288 cases of thyroid swellings were aspirated in our two-year study period. Cases were divided into four groups, namely, aspiration inadequate where diagnosis was not offered; a nonneoplastic group which included different goiters and thyroiditis; an indeterminate group which included cases showing features of follicular or Hurthle cell neoplasms, and a malignant group that included nonfollicular malignant tumors of the thyroid. Cases showing cytohistologic disparity were reevaluated. Results: Almost 14% of the cases could not be reported because of inadequate aspiration, however, an overall cytohistological correlation was achieved in 82.66% of all cases. Sensitivity and specificity for the diagnosis of malignancy were 92.7 and 98.2%, respectively. There were four false negative malignant cases with one false positive case and 13 cases failed to show any cytohistological correlation. Conclusions: FNAC is the single most important test for preoperative assessment of thyroid pathology if attention is paid to the clinical features and collection of samples from proper sites.