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An ultra-sensitive bimetallic surface plasmon resonance biosensor has been proposed for trace of malaria disease at different stages. The structure of device is based on Kretschmann configuration and consist of several layers such as BK7 prism, silver (Ag) metal layer, zinc telluride (ZnTe), and lead titanate (PbTiO3). The performance of proposed sensors is based on angular interrogation method. This sensor has the capability of detection of various stages of malaria disease and covers a wide range of refractive index (RI) from 1.370 to 1.410 for which optimize angular sensitivity 253°/RIU obtained. The malaria infection has several stages such as ring stage, trophozoite stage, and schizont stage. The refractive indexes 1.396, 1.381, and 1.371 are analyzed and corresponding angular sensitivity are 364°/RIU, 296°/RIU, and 267°/RIU respectively. The proposed SPR sensors have excellent performance for ring stage detection and detect various cancerous cells. MATLAB 2017b software is used for simulation study. [ABSTRACT FROM AUTHOR]

Objective- In this study we have analysed the eclampsia cases and evaluated the maternal and perinatal outcome. Material and Methods- the study was carried out from March 2021-Feb 2022 in Jawaharlal Nehru Medical college and hospital, Bhagalpur, Bihar. Results:- The period prevalence of eclampsia at our centre was 13%. Majority of the cases of eclampsia were referred cases from adjoining districts. An average age of presentation was between 20-29 years and nearly 3/4th of the cases was primigravida. Nearly 40% cases had some form of medical complications and around 65% had obstetrical complications due of eclampsia. Maternal mortality at our centre due to eclampsia was 9.6% and perinatal loss was 14.3%. Conclusion: - The importance of adequate antenatal care and early detection of pre-eclampsia syndrome can reduce the frequency of their morbid condition in pregnancy. Timely referral of these women by the healthcare providers in peripheral centres can help them in seeking optimum management. [ABSTRACT FROM AUTHOR]

• Chlorogenic acid (CGA) is polyphenol and the ester of caffeic acid and quinic acid. • Coffee is the largest commercial natural source of CGA. • CGA possesses powerful antioxidant, anti-inflammatory and antiapoptotic effects. • CGA attenuates cholesterol synthesis, glucose-6-phosphorylase level and lipogenesis. • Patents filed on nutraceutical use of CGA indicate its commercial potential. Chlorogenic acid (CGA) is a naturally occurring polyphenolic acid from the family of hydroxycinnamic acid, often found in green coffee extract and tea. CGA is chemically called as 5-O-caffeoylquinic acid (5-CQA) which is a more prevalent isomer of CGA. The role of CGA as an anti-oxidant, hepatoprotective, cardioprotective and neuroprotective agent has been explored by several researchers. In addition, it has anti-inflammatory, anti-microbial, anti-viral and anti-hypertensive activities. CGA has been found to be antimicrobial against a broad variety of species, including bacteria, yeasts, moulds, viruses, and amoebas. These antimicrobial capabilities might be beneficial to the food industry's ongoing hunt for novel and natural compounds for food preservation. Additionally, CGA could also alter the glucose and lipid metabolism in both genetically susceptible and healthy metabolic diseases. Because of these characteristics, chlorogenic acid is an attractive choice for the creation of dietary supplements and functional foods. This comprehensive review mainly aims to explore various sources of CGA along with its medicinal values, chemical synthesis and various derivatives obtained from CGA. The mechanism of action, therapeutic applications, regulatory concerns related to CGA are also discussed in detail. Search engine resources such as Google, Google Scholar, PubMed, Google Patent, Web of Science, and bibliographic databases of previously published peer-reviewed review papers and research works were used to gather information regarding CGA. The gathered data sets were organised sequentially in order to have a better grasp of CGA's potential. The challenges of poor solubility and poor bioavailability and development of novel drug delivery systems to overcome them has also been discussed. [ABSTRACT FROM AUTHOR]

A novel surface plasmon resonance-based biosensor for SARS-CoV-2 virus is proposed in this article. The biosensor is a Kretschmann configuration-based structure that consists of CaF2 prism as base, at which silver (Ag), TiO2, and MXene nanolayers are used to enhance the performance. Theoretically, the performance parameters have been investigated by means of Fresnel equations and transfer matrix method (TMM). The TiO2 nanolayer not only prevents oxidation of Ag layer but also enhances the evanescent field in its vicinity. The sensor provides an ultrahigh angular sensitivity of 346°/RIU for the detection of SARS-CoV-2 virus. Some other performance parameters, including FWHM (full width at half maxima), detection accuracy (DA), limit of detection (LOD), and quality factor (QF) have also been calculated for proposed SPR biosensor with their optimized values 2.907°, 0.3439 deg−1, 1.445 × 10−5, and 118.99 RIU−1, respectively. The obtained results designate that the proposed surface plasmon resonance (SPR) based biosensor has notably enhanced angular sensitivity as compared to previous results reported in the literatures till date. This work may facilitate a significant biological sample sensing device for fast and accurate diagnosis at early stage of SARS-CoV-2 virus. [ABSTRACT FROM AUTHOR]

Novel solar power technologies are constantly evolving and improving, and this is seen as a potential way to meet the increasing demand for electricity and energy on a global scale. Quantum dot solar cells (QDSCs) are one of the most optimistic third‐generation solar cells. Because of the superior qualities, such as its size, tuneable bandgap, high stability, and extremely low cost, quantum dots (QDs) have drawn a lot of attention in photovoltaic applications for highly effective solar cells. Herein, WO3 is utilized as the electron transport layer (ETL), MoTe2 as the hole transport layer (HTL), and lead sulfate treated with tetrabutylammonium iodide (PbS‐TBAI) as the QD absorber layer. Overall optimization still represents an obstacle to raise the efficiency of QDSC. Temperature, series–shunt resistance, and absorber layer thickness are optimized, and further analysis is done for overall optimization on the contour plot of electron affinities of HTL and ETL. For all aspects of simulation work, the SCAPS‐1D simulator program is employed. Fill factor 85.96%, open‐circuit voltage 923.7 mV, short‐circuit density 38.61 mA cm−2, and power conversion efficiency 30.66% are the values of the optimized performance parameters. The improved high efficiency of the proposed device can pave for the fabrication of QDSC. [ABSTRACT FROM AUTHOR]

The Pechini sol-gel reaction technique has been used to produce Tm3+, Yb3+ co-doped YVO 4 and Li+/K+/Zn2+ codoped YVO 4 : Tm3+,Yb3+ phosphors. Post-heat treatment (at 800 °C) was given to all the samples to strengthen the material's structural and optical characteristics. Prepared phosphors exhibit blue and near-infrared (NIR) light. The crystalline structure and morphology of the prepared phosphors were studied by using powder X-ray diffraction (PXRD), Fourier transform Infrared spectroscopy (FTIR) and scanning electron microscope (SEM). All prepared phosphors crystallise in the tetragonal crystal structure having space group I 4 1 / amd. Prepared phosphors, when pumped with the laser at 980 nm, give strong upconversion emission in blue and NIR regions that correspond to Tm3+ transitions 1G 4 →3H 6 and 3H 4 →3H 6 , respectively. Li+/K+/Zn2+ co-doping enhances the luminescence intensity significantly. Among Li+/K+/Zn2+ ions, Zn2+ co-doping increases the upconversion emission intensity mostly compared to others, the blue emission intensity get increased by ∼7 times and the NIR by ∼6 times. The main cause of enhancement in the emission intensity may be primarily due to the charge imbalance and asymmetry in the crystal field. Further, optical temperature sensing was also investigated by using the fluorescence intensity ratio (FIR) of the transitions (3F 2,3 →3H 6) and (3H 4 →3H 6). Co-doping of Li+/K+/Zn2+ ions also affects the temperature sensitivity. The relative sensitivity and absolute sensitivity of the samples were also calculated. This study indicates that this phosphor is a suitable candidate as a blue phosphor for display devices, WLEDs and optical temperature-sensing probes. [ABSTRACT FROM AUTHOR]

This paper presents an efficient approach to estimate the failures of various components in an induction motor using motor current signature analysis. Conventional sensor-based fault detection methods lead to huge manpower and require greater number of sensors. To overcome these drawbacks, current signature base fault detection is proposed. An advanced spectral analysis, namely discrete wavelet transform (DWT), is used for frequency domain analysis. This paper also presents fault severity estimation using feature extraction-based evaluation of DWT coefficients. As the DWT gives many coefficients at higher level decomposition which is essential for high resolution, fault classification and severity index become challenging. To address this issue, artificial neural network (ANN) algorithm is used after DWT decomposition. The fault severity is predicted by proposed fault indexing parameter of various features like energy, standard deviation, skewness, variance, RMS values. Conventional algorithms like support vector machine, k‐nearest neighbour, local mean decomposition-singular value decomposition and extreme learning machine have given maximum of 98–99% accuracy, Whereas the proposed DWT-based ANN has given 100% accuracy with tanh function. Moreover, the testing loss with this function is also very less. Experimental results have affirmed the accuracy of proposed fault detection of various faults in induction motor of rating 3—Phase, 1. 5KW, 440 V and 50 Hz. [ABSTRACT FROM AUTHOR]

Aims and background: Postoperative seroma is a common complication of laparoscopic mesh repair of direct inguinal hernia. Several kinds of attempts have been made to reduce its incidence though they are not without problems. The aim of this study was to evaluate the efficiency of a new alternate technique that must be safe and with fewer complications, using a widely available and inexpensive pre-tied suture loop (endoloop) for plication of the weakened transversalis fascia (TF)/pseudosac. Materials and methods: A prospective cohort study of 47 patients diagnosed with a total of 63 direct inguinal hernias during a 57-month period fit for laparoscopic tranabdominal preperitoneal (TAPP) meshplasty. Each of the M2 or M3 direct defects, according to the European Hernia Society (EHS), was systematically repaired by TAPP using pre-tied suture loop application at the base of TF. Patients were reviewed during follow-up at 2, 6 weeks, and 1 year after the operation to look for primary postoperative outcome parameters, i.e., seroma formation; secondary outcome parameters, i.e., groin pain, wound infection, and recurrence. Results: During the follow-up period, no patient presented with seroma formation and wound infection. Only two patients had complaints of groin pain at 2-week follow which was resolved by analgesics and there was no hernia recurrence after a follow-up of 1 year. Conclusion: Application of a pretied suture loop at the base of TF during laparoscopic repair of direct inguinal hernia is cost effective, safe method and does not increase the risk of seroma formation and recurrence. Clinical significance: Seroma formation is a major concern for surgeons as well as patients during postoperative period following laparoscopic inguinal hernia repair. The development of a cost-effective, reliable technique with the least or no seroma formation and recurrence prevention is needed at this time. [ABSTRACT FROM AUTHOR]

• Quantum mechanical computations have been conducted on the mesogenic compound 4EHB. • Optimization and electronic properties estimation have been carried out through B3LYP/6-31 g(d,p) level. • Intermolecular interaction energies between pairs of 4EHB have been estimated using M06-2X/6-311 g(d,p) theory. • These computations have provided insights into the mesogenic behavior of the system. The molecule 4-ethoxy-N-(4-ethoxy-2-hydroxybenzylidene)benzohydrazide (4EHB) is characterized by a rigid aroylhydrazone core, acting as a mesogenic unit, and a flexible chain at its terminal end. The aroylhydrazone core comprises two aromatic rings linked by connecting groups, resulting in moderate size and elongation of the molecule. Variations in the positions and orientations of elongated molecules give rise to different mesogenic phases such as Nematic, Smectic, and Hexatic Smectic. The mesogenic behavior of aroylhydrazone-based materials is governed by various non-covalent interactions. In this study, molecular geometry optimization, analysis of HOMO-LUMO orbitals, and MEP surfaces of individual and pairs of 4EHB molecules were conducted using the Density functional B3LYP technique with the basis set 6-31G**. Intermolecular interaction energies between pairs of 4EHB molecules are evaluated using the technique M06-2X/6-311G** in stacking, terminal, and side-to-side (in-plane) configurations. Basis set superposition error (BSSE) is corrected using counterpoise method and interaction energy(I.E.) is decomposed in different components using SAPT0 method at level 6-311G**, which provided insights into the mesogenic behavior of the system. [ABSTRACT FROM AUTHOR]

This paper presents the detection of electrical faults in three phase induction motor using improved resolution of Gabor Analysis (GA) by quadrature stator current (QSA). Resolution problems associated with conventional spectral analysis of stator current need to be addressed for incipient faults. In particular, rotor faults will develop characteristic frequencies as side bands of fundamental and its harmonics. Moreover, these frequencies are spread over the spectrum as the motor is operated at variable speeds. Conventional spectral analysis has not shown satisfactory results due to various reasons like domination of healthy components, noise, and resolution problems. This is a major issue at low slip value of motor especially. This paper proposes Park's Vector Transformation to get quadrature component of stator current which overcomes the domination problems, and the de-noising will eliminate the noise with suitable threshold value, whereas the resolution issue is solved using proposed GA and the severity is estimated with feature extraction parameters. The fault indexing parameters of proposed Gabor analysis have improved by 40–60% compared to conventional wavelet analysis. The perfectness of proposed fault estimation is examined using experimental validation on a 3 phase induction motor of 1.5kW test bed. [ABSTRACT FROM AUTHOR]

In this article, a highly sensitive surface plasmon resonance biomedical sensor based on barium titanate, MXene and nickel hybrid nanostructure has been reported. The present paper is based on a modified Kretschmann configuration. In this configuration, multilayers are vertically stacked together to improve the optical and electronic properties of the proposed surface plasmon resonance sensor. Barium titanate and MXene have unique properties like large surface area, chemical stability, tunable bandgap, small work function, layered structure and good matter-light interaction to improve the performance parameters of the proposed surface plasmon resonance sensor. Nickel also plays a vital role to enhance the performance parameters because it has high metallic conductivity, a large number of absorption sites and hydrophilicity. The optimized performance parameters are angular sensitivity (3160RIU−1), detection accuracy (0.3072 deg−1), figure of merit (97.075 RIU−1) and limit of detection (3.164 × 10−6) for CaF2 prism/Ag/BaTiO3/Ni/MXene/Sensing medium at 633 nm wavelength. The strong transverse magnetic field intensity is also plotted for the biomedical sensor to analyze the penetration depth. The designed surface plasmon resonance sensor's optimal penetration depth into the sensing medium is 137 nm. The above results will open a new way to design and develop such type of surface plasmon resonance biomedical sensor. [ABSTRACT FROM AUTHOR]

The immune system is the armor of body, which stands against the infection and various diseases. Immune suppression/stimulation may lead to variety of disorders. Immunomodulators help to balance immunity that induces (stimulation) or attenuates (suppression) according to the therapeutic need. From ancient times, natural products have been utilised for the modulation of immune system. Traditional system of medicines such as Ayurveda, Unani, Traditional Chinese medicine (TCM) describes varieties of evidences for the vast pharmacological activity. Some of the major plant-derived compounds potentially explored as immunomodulators i.e. curcumin, resveratrol, epigallocatechin-3-gallate, andrographolide, genistein etc. Present review will provide an overview on plant-derived immunomodulator metabolites and their effects on immune system. [Display omitted] • Natural products have been utilised for potential immunomodulatory activities. • Treatment of various diseases viz cancer, diabetes, anti-inflammatory, respiratory diseases etc. using plant products is discussed. • Phytoconstituents viz curcumin, resveratrol, epigallocatechol-3-gallate, quercetin, colchicine, capsaicin, andrographolide etc. as immunomodulatory effects in preclinical studies, and clinical studies are discussed. • The significant uses and some mechanism of medicinal plants as immunomodulatory agents with possible uses for human and animal health are highlighted. [ABSTRACT FROM AUTHOR]

• Curcumin, a wonderful spice, utilized as a condiment, a flavouring and colouring agent in different food preparations and numerous health benefits. • Owing to poor aqueous solubility of curcumin, wide-ranging first pass metabolism, rapid excretion, and subsequent low bioavailability are the limitations. • Need to search for an alternate method for successful commercialization of curcumin in a suitable dosage form. • Mechanism of curcumin for treating different disorders and its applications in clinical and preclinical use. • Numerous studies reported to improve its solubility which ultimately enhanced its bioavailability and therapeutic effectiveness. Curcumin is a polyphenol which is derived from the rhizomes of Curcuma longa. From the last few decades, it is utilized as a condiment, a flavouring and colouring agent in different food preparations. Owing to its potential, it also possesses anti-inflammatory, anti-hyperglycemic and neuroprotective actions and has shown preventive actions against various disorders such as cardiovascular, diabetes, brain and many more. In spite of numerous health benefits, the use of curcumin in humans for treatment of several diseases is limited owing to its poor aqueous solubility, wide-ranging first pass metabolism, rapid excretion, and subsequent low bioavailability. Various preclinical and clinical studies of curcumin have pointed out that curcumin plays a role in treatment of different disorders. However, many of the curcumin formulations do not comply much for their safety, stability and efficiency assessment. Henceforth, there is a need to search for an alternate method for successful commercialization of curcumin in a suitable dosage form. In this review we aim to summarize the mechanism of curcumin for treating different disorders and various clinical and preclinical studies conducted on curcumin polyphenol. Further, numerous studies have done in the past to improve its solubility which ultimately enhanced its bioavailability and therapeutic effectiveness have also been summarized. [ABSTRACT FROM AUTHOR]

Objective To report experiences in Bihar, India's most densely populated state, with a state government programme to train community health workers (CHWs) to combat the coronavirus disease 2019 (COVID-19) pandemic in the state's predominantly rural population of 128 million. Methods In May 2021, during the second wave of the COVID-19 pandemic in India, the Bihari government initiated a 1-day COVID-19 training programme for rural, unaccredited CHWs who had recently completed a community health education course from the National Institute of Open Schooling. The use of primary health centre buildings and doctors to deliver COVID-19 training and the existence of certification data on CHWs who participated in the community health education course streamlined implementation and minimized costs. After COVID-19 training, CHWs were paid as first responders and COVID-19 treatment workers by the Bihari government. Findings Overall, 15 000 CHWs in Bihar completed the COVID-19 training programme in 2021 and a further 30 000 were enrolled. A survey of CHWs carried out after COVID-19 training had started found that 80% (81/102) were satisfied with training and felt they were receiving information from reliable sources. Conclusion The training and mobilization of a team of CHWs helped ease pressure on a stressed, rural, health-care system in Bihar and improved its preparedness for future COVID-19 outbreaks. The success of the training programme illustrates how local initiatives can help address gaps in the health workforce and extend the reach of public health care into rural areas, in addition to improving COVID-19 responses. [ABSTRACT FROM AUTHOR]

The role of mushroom polysaccharides and probiotics as pharmaceutical excipients for development of nanocarriers has never been explored. In the present study an attempt has been made to explore Ganoderma lucidum extract powder (GLEP) containing polysaccharides and probiotics to convert liquid self nanoemulsifying drug delivery system (SNEDDS) into solid free flowing powder. Two lipophilic drugs, curcumin and quercetin were used in this study due to their dissolution rate limited oral bioavailability and poor permeability. These were loaded into liquid SNEDDS by dissolving them into isotropic mixture of Labrafill M1944CS, Capmul MCM, Tween-80 and Transcutol P. The liquid SNEDDS were solidified using probiotics and mushroom polysaccharides as carriers and Aerosil-200 as coating agent. The solidification was carried out using spray drying process. The process and formulation variables for spray drying process of liquid SNEDDS were optimized using Box Behnken Design to attain required powder properties. The release of both drugs from the optimized spray dried (SD) formulation was found to be more than 90%, whereas, it was less than 20% for unprocessed drugs. The results of DSC, PXRD and SEM, showed that the developed L-SNEDDS preconcentrate was successfully loaded onto the porous surface of probiotics, mushroom polysaccharides and Aerosil-200. [ABSTRACT FROM AUTHOR]

The rolling elements of the induction motor are highly susceptible to faults. The detection and diagnosis of rolling element faults are accurate and reliable only when the extracted features are accurate. The paper proposes an approach for bearing and rotor fault diagnosis using deep optimal feature extraction and selection based on vibration signal analysis. The deep feature extraction is done using an ensemble deep models features extraction approach in which features are extracted from seven pretrained models are fused serially using serial-based feature fusion technique. This leads to a solution for a higher efficacy model, but at the cost of high processing time as the feature data set gets large. A unique approach termed Ensemble Feature Selection has been developed to address this issue and limit the harmful impact of unwanted features in data-driven diagnostics. The processing time is further reduced using the shallow classifier at the fully connected layer. The proposed model is tested using the data acquired in the laboratory and validated using the available online benchmark data sets. [ABSTRACT FROM AUTHOR]

The present investigation is focused on improving oral bioavailability of poorly soluble and lipophilic drugs, curcumin (CRM) and duloxetine (DXH), through the solid self-nanoemulsifying drug delivery system (S-SNEDDS) and identifying their potential against attenuation of NP in chronic constriction injury (CCI)–induced rats through the solid self-nanoemulsifying drug delivery system (S-SNEDDS). The optimized batch of S-SNEDDS reported was containing CRM and DXH (30 mg each), castor oil (20% w/w), tween-80 (40% w/w), transcutol-P (40% w/w), and syloid 244 FP (1 g). The high dose of each of naïve CRM (NCH), naïve DXH (NDH), physical mixture of DXH and CRM (C-NCM-DXH), S-SNEDDS-CRM (SCH), S-SNEDDS-DXH (SDH), and S-SNEDDS-CRM-DXH (C-SCH-SDH) was subjected for MTT assay. The developed formulations were subjected to pharmacokinetic studies and results showed about 8 to 11.06 and 2-fold improvement in oral bioavailability of CRM and DXH through S-SNEDDS. Furthermore, CCI-induced male Wistar rats were treated with SSNEDDS containing CRM and DXH, S-SNEDDS containing individual drug, individual naïve forms, and their combination from the day of surgery for 14 days and evaluated for behavioral at pre-determined time intervals. On the terminal day, animals were sacrificed to assess tissue myeloperoxidase, superoxide anion, protein, tumor necrosis factor-α, total calcium levels, and histopathological changes. Pronounced effect was observed in rats treated with S-SNEDDS containing both drugs with respect to rats receiving any of other treatments owing to enhanced oral bioavailability through S-SNEDDS. Therefore, it can be concluded that S-SNEDDS of both drugs and their coadministration can accelerate the prevention of NP. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a metabolic disorder due to increased level of glucose in blood that affects millions of individuals. If not managed properly, it can lead to life threatening complications, organ failure and mortality. Research has recognized that diabetes can be prevented and managed by following proper lifestyle which includes diet and exercise. Though a number of synthetic drugs are available for managing this condition, their long-term use is associated with many side effects. This has shifted the research towards medicinal plants and herbs which are considered to be comparatively safe. Edible mushrooms belong to the class of potential anti-diabetic phytotherapy. They are rich in natural compounds such as fibers, polysaccharides, phenolics and alkaloids and known for providing antidiabetic, antioxidant and antihyperlipidemic effects from ancient times. Moreover, mushroom polysaccharides also act as prebiotics and modulate the composition of gut microflora; and thus, can reduce insulin resistance. The present review discusses the pathophysiology of diabetes and, elaborates some potential mushroom species that are known to have antihyperglycemic activities. Different mushroom polysaccharides modulating the composition of gut microflora in diabetic animal models have also been discussed. • Mushrooms are well known for their anti-inflammatory and anti-oxidant properties. • Mushrooms contain numerous bioactive constituents such as polysaccharides and fiber. • The polysaccharides from mushroom (PM) are effective against T2DM by reducing oxidative stress. • PM also act as prebiotics and reduce gut dysbiosis thereby help in managing insulin resistance and T2DM. [ABSTRACT FROM AUTHOR]

The offshore regions typically experience greater wind speeds, which makes offshore Wind Turbines (WTs) more efficient. This enhanced output comes with a price, including more maintenance requirements, greater proneness to malfunctions, and difficulties with accessibility. It is challenging to gather the signatures with invasive sensors from offshore WTs for a long time due to the surrounding conditions. Sensors get displaced from their positions, and the acquired data becomes less reliable. The issues with invasive sensors in offshore locations for WTs are addressed in the study by presenting a non-invasive method for fault detection in offshore WTs using thermography. The approach is able to classify 11 different health conditions of WTs such as healthy, single-multiple phase stator faults with different shorting percentages, cooling fan faults, and rotor faults. Serial Based Feature Fusion technique is proposed in which features are extracted from seven Pre-Trained (PT) models and fused to get a feature set with advantages of individual PT model. The problem of high processing time and complexity a Hybrid Feature Selection technique is proposed in which the feature selection is done in two stages along with hyperparameter tuned Shallow Learning (SL) Classifier at the output layer. The algorithm is tested for multiple combinations of DNN and SL approaches. The highest achieved efficacy is 100%. By using feature set with best possible feature, the suggested model is more reliable. Additionally, it eliminates the necessity for segmentation and clustering, which reduces the computational burden and time required for diagnosis. [ABSTRACT FROM AUTHOR]

Abrasive flow finishing (AFF) is an advanced finishing process employed for finishing macro- to micro-features of workpieces. Finishing improves the functioning of the components by reducing their surface roughness. AFF process uses a polymer-based flexible medium containing abrasive particles as a finishing tool. Medium used during the AFF process plays a vital role in deciding the final surface roughness on the workpiece surface. It is the medium properties in combination with AFF input parameters that decide the end surface roughness. Micro-features on the components are mostly machined with the help of processes involving thermal energy (electrical discharge micro-machining, laser beam micro-machining). This leads to the formation of hard recast layer on the micro-machined workpiece surface. Component size and hardness of the recast layer possesses a great challenge to the finishing processes. In the current article, an economic viscoelastic medium is developed for the finishing of micro-features and its detailed rheological study is carried out. Later, experimental study of the AFF process during the finishing of micro-slots (440 ± 10 µm width) in surgical steel is performed. Developed medium successfully finishes the micro-slots with an initial surface roughness of 3.54 µm to a final surface roughness of 0.21 µm (94.07% reduction in surface roughness). [ABSTRACT FROM AUTHOR]

The study entailed formulation of gold nanoparticles (AuNPs) upon reduction of chloroauric acid by modified apple polysaccharide (MAP). AuNPs were conjugated with insulin (INS) for its oral delivery to treat type 1 diabetes mellitus (DM). The size of MAP conjugated AuNPs loaded with INS was 124 ± 8.55 nm with zeta potential −10.5 ± 0.54 mV. The animal study carried out in streptozotocin induced rat model revealed that AuNPs conjugated insulin (AuNPs-INS) in high dose caused 3.36 folds decrease in blood glucose level in 240 min, whereas, orally administered INS failed to decrease the blood glucose level. The 28-day study also revealed better improvement in body weight, lipid profile, urea, creatinine and liver parameters in AuNPs-INS (high dose) for which the observed value was close with respect to intraperitoneally administrated insulin followed by medium dose of AuNPs-INS, low dose of AuNPS-INS, AuNPs alone and modified apple polysaccharide. Unlabelled Image • Gold nanoparticles (AuNPs) were prepared by reducing HAuCl 4 using MAP. • Insulin was conjugated to AuNPs. • Insulin conjugated AuNPs were used to treat diabetes in rats. • The orally delivered insulin conjugated AuNPs were found successful to treat diabetes. [ABSTRACT FROM AUTHOR]

• Pharmacological activities and molecular targets of quercetin. • Mechanistic pathways of quercetin for treating different diseases. • Formulation strategies for improving the bioavailability of quercetin. Quercetin is reported to have numerous pharmacological actions, including antidiabetic, anti-inflammatory and anticancer activities. The main mechanism responsible for its pharmacological activities is its ability to quench reactive oxygen species (ROS) and, hence, decrease the oxidative stress responsible for the development of various diseases. Despite its proven therapeutic potential, the clinical use of quercetin remains limited because of its low aqueous solubility, bioavailability, and substantial first-pass metabolism. To overcome this, several novel formulations have been reported. In this review, we focus on the applications of quercetin extract as well as its novel formulations for treating different disorders. We also examine its proposed mechanism of action of quercetin. [ABSTRACT FROM AUTHOR]

This paper focuses on estimating the product of two population means. Within this paper, we have introduced three distinct classes of estimators for product of two population means. These estimators take into account the known population mean of an auxiliary variable under the framework of stratified random sampling and the presence of non-response in the study variable. Basically, for case (I) we assume the non-response on the study variable and utilize the auxiliary information corresponding to the responding units of the study variable and in case (II), we utilize the complete dataset from the auxiliary variable while also accounting for non-response in the study variable. In case (III) we combined both the information of the auxiliary variable and assumed the non-response on the study variable. Expressions for bias and mean square error have been derived, extending up to the first-order derivative. We have also pinpointed some specific members of the proposed estimator. We have conducted a simulation study to evaluate the valuable insights into the performance of the suggested classes of estimators with the conventional estimator. [ABSTRACT FROM AUTHOR]

[Display omitted] • We report a temperature sensing-luminescent material YVO 4 : Tm3+, Yb3+ codoped with Li+ which can emit in blue and NIR region under NIR (980 nm) excitation. • The luminescent material may have application in non-contact optical thermometry/ imaging and in display devices. • YVO 4 doped with Tm3+, Yb3+ phosphor crystalizes into tetragonal crystal structure with space group I41/amd. Nonlinear photon upconversion properties of co-doped materials were studied under NIR (980 nm) laser excitation. • From the laser input power dependence studies, three photon involvements for blue and 2 photon for NIR emission were observed for optimized Li+ co-doped Tm3+ Yb3+ in YVO 4. • A possible energy transfer mechanism is given and discussed using energy level diagram. • Temperature-dependent upconversion data used to determine the material's sensitivity, that justifies its application as a non-contact temperature sensing probe. A series of Li+ codoped YVO 4 : Tm3+/Yb3+ phosphors were prepared by Pechini sol–gel reaction technique. Structural study of the material confirms the crystal structure of the prepared samples and also gives information about the crystallite size and phase purity with the variation of Li+ ion concentrations. Emission peaks around ∼ 476, and ∼ 799 nm corresponds to the 1G 4 →3H 6 , and 3H 4 →3H 6 transitions, which could be seen under irradiation of NIR (980 nm) laser light. Li+ (10 mol%) codoped sample shows maximum upconversion. Li+ doping significantly increases the up-conversion emission intensities by more than 5 times for emission peaks around 476 nm and 799 nm.The possible explanation for the increase in UC (Upconversion) emission intensity is attributed to both improved crystallinity and crystal field modification around Tm3+ ions. The variation of UC emission spectra with respect to pump power was observed to investigate the underlying UC luminescent mechanism in YVO 4 : Tm3+/Yb3+ codoped with Li+ (10 mol%). The multiphoton involvement is observed in the power-dependent study of upconverted blue and NIR emission bands. Widely used fluorescence intensity ratio (FIR) technique was used to evaluate the temperature sensing capability of the optimized Li+ codoped phosphor. The FIR study of Stark components 3F 2 , and 3H 4 levels indicates that this material is an efficient material for temperature sensing. The optimized sample, doped with Li+, exhibits relative sensitivity of 0.78% K−1 at a temperature of 548 K. This material have utility in both light-emitting diodes and as a temperature-sensing probe. [ABSTRACT FROM AUTHOR]

Graphite is the most suitable material as dry lubricant. However, its application as a lubricant is limited with necessity of moisture vapors. Alternatively, polytetrafluoroethylene (PTFE) has an excellent lubrication property but does not have mechanical characteristics. The effect of gamma radiation doses on the lubrication behavior of graphite –PTFE (Inoflon A-408) system has been studied using (TR-TW-30L) tribotester with thrust washer attachment. Different compositions of graphite and PTFE were prepared and irradiated by gamma rays. Improved tribological properties of graphite –PTFE system showed by decrease in coefficient of friction and wear. SEM-EDX, XRD and contact angle analysis confirm fluorination of graphite by gamma radiation exposure leading to the development of novel dry lubrication system. [ABSTRACT FROM AUTHOR]

Abstract Modified Apple Polysaccharide (MAP) has been reported to cure colorectal diseases by up-regulating apoptosis and down regulating metastasis. In the present study, mesalamine (MES) and MAP mini tablets have been prepared and co-administered with probiotics to provide site specific release of drug. Probiotics along with MAP, which acts as a prebiotic would replenish the colonic microflora that have been compromised due to colorectal pathology. MES mini tablets were prepared keeping guar gum in the core and coating them with Eudragit S100 and guar gum. The optimized batch was explored for its curative potential on acetic acid induced ulcerative colitis (UC) in rat model with and without administration of probiotic and MAP. The results revealed that the rats treated with the combination of MAP and MES mini tablets along with probiotics show maximum curative potential. It was also observed that MAP mini tablets show better curative potential as compared to probiotics. The results of disease activity index, macroscopic scoring, antioxidant studies, tumour alpha and histopathological examination suggested that the rats treated with combination of MES-MAP mini tablets and probiotics have maximum therapeutic effect followed by MES mini tablets alone, MAP mini tablets alone and probiotics. Highlights • Liquid MAP was extracted from apple and solidified using spray drying. • MAP and MES mini tablets were prepared. • MES mini tablets were coated with guar gum and Eudragit S100 for colon specific delivery. • MAP and MES tablets were co-administered with probiotics to UC induced rats. • MES with MAP and probiotics showed higher efficacy to treat UC compared to other treatments. [ABSTRACT FROM AUTHOR]

Surface roughness is one of the critical parameters that affect the component performance during its working life. To develop any process to its full potential, it is necessary to understand the physics of that process. Abrasive flow finishing (AFF) is one of the advanced finishing processes. In the current research work, an effort is made to understand physics and mechanism of surface roughness improvement during the AFF process. This research paper is divided into two sections. Firstly, the amount of finishing stresses and forces generated during the finishing of microholes fabricated on surgical stainless steel (316L) workpieces are computed by using the finite element method. Finishing stresses are generated in the viscoelastic medium. So, to compute finishing stresses, finite element analysis of the viscoelastic medium is carried out by incorporating its experimentally measured rheological properties. Finishing stresses are calculated along the circumferential direction of the microhole. Later, at the same workpiece surface location, simulated and experimentally measured surface roughness value are compared. Secondly, a new simulation model is proposed to predict the surface roughness on the microhole wall surface for various AFF input parameters. Maximum percentage change in surface roughness error of 8% is observed between simulated and experimental results after AFF process. [ABSTRACT FROM AUTHOR]

Abstract In the present study application of Modified Apple Polysaccharide (MAP) as tablet binder was evaluated. Liquid MAP was extracted from apple and solidified by adsorbing it on porous surface of Aerosil-200 and trehalose and this dispersion was dried using spray dryer. The concentration of excipients as well as spray drying conditions was optimised by using Box Behnken Design to achieve desirable powder characteristics. The optimised batch of solid MAP was characterized by DSC, PXRD, SEM, and FT-IR studies that confirmed complete adsorption of liquid MAP on the surface of Aerosil-200 and trehalose. This solid MAP was investigated for its binding efficacy for tablet formulation and its binding potential was compared with acacia and polyvinyl pyrrolidone K-30. Mesalamine (model drug) granules containing different concentration of binders were prepared by wet granulation. The granules were evaluated for micromeritic properties and results were found within the pharmacopoeial limits. The prepared tablets were subjected for post compression studies such as hardness, friability, disintegration, dissolution, physical stability, content uniformity and percentage elastic recovery and their results were found good. At 2.5% w/w concentration in tablet, the solid MAP has shown shorter disintegration time and faster dissolution profile as compared to other concentrations used including good physico-mechanical properties. Highlights • Aqueous extract of MAP was solidified by using Aerosil-200 and trehalose • Spray drying was used to solidify liquid MAP • BBD was used to optimize formulation and spray drying process • Tablets with solid MAP as binder were having good physico mechanical properties • Solid MAP (2.5% w/w) showed faster dissolution profile [ABSTRACT FROM AUTHOR]

Human gait data becomes very helpful in the prediction and correction of movement control while walking. In many areas like medical practices, Physical fitness training programs, rehabilitation techniques and prosthesis performance, gait study has its significant scientific relevance and applications. This study aims to predict the performance of Jaipur knee joint in terms of gait symmetry with transfemoral Indian amputees. First time we tried to calculate gait symmetry of widely used Jaipur knee joint with Indian population. This aspect has not been focused so far with Indian amputees. 11 unilateral transfemoral amputees (9 men and 2 women; average age 45 years, range 31-58 years) participated in the study. Subjects were using prosthesis with Jaipur knee for long time (mean: 16 yrs; range: 5-27 yrs). To investigate the gait function with 6 Vicon cameras 3D motion analysis system (Kinematrix system) participants were asked to walk with their comfortable speed. Gait symmetry, might be the basis of recommendation of knee joint. Kinematics parameter is predicted quantitavely gait symmetry with Jaipur knee joint. This research will result in significant prevention of degenerated musculoskeletal effects in future generally seen in unilateral transfemoral amputees. [ABSTRACT FROM AUTHOR]

Schematic illustration of sensing mechanism of surface-anchored recognition probes at glass substrates and orientation transitions of the 5CB molecules filled in Cu TEM-grid from homeotropic orientation to planar/tilted orientation after incubation of (a) metal-free and (b) metal-containing water at the optical-platform. Then, the water droplet was removed and 5-CB filled TEM grid was placed on it to study optical response (c and d). [Display omitted] • Development of liquid crystal based sensor for nickel(II) detection in water samples using surface anchored diacetate probes. • This sensor can quantitatively determine nickel contamination up to 0.08 M in water and 0.8 M in drinking water samples. • This smart-fabrication method is a promising tool for nickel(II) pollution control. Rational fabrication approach for ultra-trace level detection of nickel (Ni(II)) ions in water samples has been developed using surface anchored recognition probes at liquid crystal sensing platform. In this system, the optimized volume per cent (5:1, %v/v) of synthesized surface anchored diacetate probes along with DMOAP decorated on glass substrate is able to perfectly align 5-cyanobiphenyl (5-CB) liquid crystal (LC) giving dark textural pattern. On the other hand, the fabricated probe is able to selectively reorient the transitions of the decorated LC molecules in the presence of Ni(II) ions too, leading to bright textural pattern under cross polarizers. The optimized and fabricated system demonstrated high selectivity and sensitivity, detecting Ni(II) ions as low as 0.08 μM (∼4.7 ppb) in distilled water and 0.8 μM (∼47 ppb) in real water with results observable to the naked eye. Moreover, the sensor can detect Ni(II) in drinking water, providing an approach to develop LC-based sensor for detection of natural water contaminants with simplified operating techniques. [ABSTRACT FROM AUTHOR]

Cystic Artery Pseudoaneurysm (CAP) is a rare, abnormal dilation of the artery supplying the gallbladder. The main causes could be acute cholecystitis and iatrogenic injury during cholecystectomy. Ruptured pseudoaneurysm of cystic artery generally presents with haemobilia, and upper gastrointestinal bleeding or intraperitoneal bleeding. Only a few cases of unruptured CAP are reported that are successfully treated with open or laparoscopic cholecystectomy. This case is one of the rare cases of unruptured CAP where a 78-year-old female patient who was a known case of hypothyroidism, presented with upper abdominal pain and vomiting, diagnosed with acute calculous cholecystitis with CAP. She was managed with laparoscopic cholecystectomy, converted to open cholecystectomy and discharged with uneventful postoperative period. Due to the high risk of rupture, the patient required urgent surgical intervention either by open or laparoscopic cholecystectomy by a skilled laparoscopic surgeon. The operating need for conversion to laparotomy should be considered neither a failure nor a complication but an attempt to avoid intra and postoperative complications. [ABSTRACT FROM AUTHOR]

In the present study, different solid self-nanoemulsifying drug delivery system (S-SNEDDS) was formulated by using porous hydrophilic and hydrophobic carriers to improve the dissolution rate and bioavailability of simvastatin (SIM). The prepared liquid-SNEDDS composed of Labrafil M 1944 CS/ Tween-80/ Ethanol (20% / 53.33%/26.67% v /v) with 0.1% SIM, resulted droplet size of 40.69 nm. The hydrophobic carriers used were Aerosil-200, Syloid 244FP, Syloid XDP 3150, Magnesium stearate, Micro Crystalline Cellulose PH102 and lactose and hydrophilic carriers used were Poly vinyl alcohol, Sodium carboxy methyl cellulose and hydroxypropyl-β-cyclodextrin. These S-SNEDDS were characterized through micromeritic, biopharmaceutical studies and stability studies. The spray dried S-SNEDDS prepared by using Aerosil 200 as hydrophobic carrier provided nanoemulsions with unchanged droplet size and drug release when subjected at different stress conditions such as thermodynamic stress and freeze thaw cycles. In vitro dissolution studies revealed that the L-SNEDDS and S-SNEDDS of Aerosil 200 were found to be remarkably superior over the unprocessed SIM and marketed SIM. Scanning electron microscope, Differential scanning calorimeter and Powder X-Ray Diffraction revealed crystalline SIM was present in a changed amorphous state in the SNEDDS formulations prepared with Aerosil 200 as carrier. Further, pharmacokinetic study carried out on rats revealed 0.5 h increase in time for maximal concentration (T max ), 3.75 folds increase in maximal concentration (C max ), 1.22 h increase in mean residence time, 1.54 folds increase in area under curve (AUC 0-t ), 2.10 folds increase in AUC 0-∞ and 3.28 folds increase in bioavailability confirms that the developed S-SNEDDS were superior than that of marketed formulation. Hence, it can be safely concluded that Aerosil 200 based S-SNEDDS were able to provide improvement in dissolution rate and oral bioavailability of SIM. [ABSTRACT FROM AUTHOR]

Surface roughness is one of the critical properties that affect the performance of biomedical devices and human implant's functions. Higher surface roughness leads to the comparatively higher probability of body fluid retention in the surface valleys. Surface roughness peaks can easily obstruct the flow of body fluid and drug. Abrasive flow finishing (AFF) is an advanced finishing process, which can produce nano-level surface finish in complex components. In this paper, experimental investigations, including parametric study on nanofinishing of surgical stainless steel 316L tubes using AFF process has been reported. Indigenous multiple polymers blended base medium was developed to perform the nanofinishing experiments. Based on the experimental results, statistical model has been presented. To understand the AFF process in depth, finite element approach has been implemented to determine the finishing forces generated during the AFF experiments. Initial surface roughness on the internal surface of the workpiece varies in the range of (0.67-0.50) µm. The best surface finish of 48 nm with a percent improvement (% ΔRa) of 92.20% has been achieved after processing the workpiece with AFF process. Simulated results are validated with the experimental results and the deviations are in the acceptable range. [ABSTRACT FROM AUTHOR]

Estimation of transient heat flux imposed on one of the surfaces of a solid medium, via an inversion algorithm, is presented. Three inversion models, utilizing temperature data obtained from thermocouples embedded inside the solid medium, are developed. These include: (i) one-thermocouple model, where Boundary Condition (BC) at one surface of the solid is known a priori ; (ii) model incorporating a semi-infinite abstraction of the solid medium; and, (iii) two-thermocouple model, where the temperature data from the first thermocouple is used for inversion and the data from the second thermocouple is used as a remote BC for the forward problem. These models are benchmarked and compared with one-dimensional heat conduction experimental data involving both, known and unknown time-varying BCs. It is found that the estimation of heat flux via the one-thermocouple model is highly dependent on the exactness of the explicitly known BC. Furthermore, the extended applicability of semi-infinite model well beyond the thermal penetration time makes them suitable for problems with unknown BCs such as nuclear reactor containments, furnaces, etc. However, as compared to both these models, the two-thermocouple model is much more versatile and robust with a wider range of applicability. This latter model overcomes the limitations of commercially available packaged thermopile flux sensors - this is demonstrated through the estimation of time varying unknown heat flux during steam condensation on a vertical flat surface. [ABSTRACT FROM AUTHOR]

An effect of gamma radiation on lubrication behavior of graphite -PTFE dry lubrication system has been studied using (TR-TW-30L) tribometer with thrust washer attachment in plane contact. Different compositions of graphite and PTFE were prepared and irradiated by gamma rays. Gamma radiation exposure significantly improves the tribological properties indicated by decrease in coefficient of friction and wear properties of graphite -PTFE dry lubrication system. SEM and XRD analysis confirm the physico-chemical modification of graphite-PTFE on gamma radiation exposure leading to a novel dry lubrication system with good slip and anti friction properties. [ABSTRACT FROM AUTHOR]

The most popular method to determine the sensitivity of surface plasmon resonance (SPR) sensors in the last couple of decades has been angular interrogation. The silver layer (Ag), a 2D layer of TiO2, and dielectric material layer such as silicon (Si) with heterostructure material graphene are all stacked in the proposed SPR sensor. To increase sensitivity of SPR sensor in the visible area, the device structure focuses on the Kretschmann configuration, by which a TiO2 sheet is sandwiched between silver and silicon sheets. The proposed device structure makes use of the operational wavelength of 633 nm. The numerical simulation has been performed in MATLAB software in this device structure. The simulation results show that an analyte of refractive indices ranges 1.345–1.350. A single layer of silicon 3 nm and TiO2 10 nm makes up the suggested SPR configuration, which increases the sensitivity to 281° RIU−1. Herein, it has also been computed the figure of merit, detection accuracy, limit of detection, full width at half maximum, and transverse magnetic electric field intensity. The biomedical and chemical fields have benefited from the proposed SPR sensor structure design. [ABSTRACT FROM AUTHOR]

Abrasive flow finishing (AFF) is one of the advanced finishing processes used mainly for finishing of complex surface features. Nano finishing of aluminum alloys is difficult using conventional finishing processes because of its soft nature. So, in this work, aluminum alloys are finished using AFF process. Since the finishing is carried out using polymer rheological abrasive medium (medium), the finishing forces on aluminum alloy workpieces are too low compared to conventional finishing processes. Thus, this process generates nano surface roughness on aluminum alloy. By using the theoretical model, change in surface roughness (ΔRa) with respect to various AFF input parameters is studied. A new simulation model is proposed in this paper to predict the finishing forces and ΔRa during AFF process. Modeling of finishing forces generated during the AFF process is carried out using ansys polyflow. These forces are used as input in the simulation model to predict ΔRa. Medium rheology decides the magnitude of the generated finishing forces in AFF process. Therefore, to predict the forces accurately, rheological properties of the medium are measured experimentally and used as input during modeling. Further, to make the simulation more realistic, abrasive particle bluntness with respect to extrusion pressure and number of strokes is considered. Because of considering these realistic conditions, simulation and experimental results are in better agreement compared to theoretical results. [ABSTRACT FROM AUTHOR]

Surface mounted sensors disturb the phenomena they are expected to record and are prone to damage in harsh environments, leading to incorrect measurements. The present study examines a robust alternative via the inverse estimation of time-dependent wall heat flux using single thermocouple data, as against an array of embedded thermocouples. The Levenberg-Marquardt algorithm for parameter estimation is employed with an even extension of truncated Fourier series as the trial function for inversion. The inversion error decreases with the length of the signal, number of harmonics in the even extension of truncated Fourier series, and proximity of the thermocouple relative to the boundary of interest. The method is numerically validated as well as experimentally benchmarked, against constant, periodic, and transient wall heat flux data in one-dimensional heat conduction problems and is seen to match the exact solution quite well. The developed method is very well suited for sensor development, particularly for application involving high heat flux. [ABSTRACT FROM AUTHOR]

In this article, we report synthesis and characterization of a novel homologous series of butyl 4-(4′-(alkoxy)-2-hydroxybenzylideneamino)benzoates, CnLH (n = 6, 8, 10, 12, 14, 16) and their copper(II) complexes. The mesomorphic properties of these compounds were investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and powder X-ray diffraction (XRD) studies. The ligands and their copper(II) complexes exhibit wide range of enantiotropic smectic A mesophase as confirmed by their typical optical texture under polarizing microscope. Thermal stability of the compounds is determined by thermo gravimetric analyses. DFT calculations have been performed using GAUSSIAN-09 program at B3LYP level to obtain the stable electronic structure of the ligand and its copper(II) complex. [ABSTRACT FROM PUBLISHER]

Temperature dependent Raman and X-ray diffraction studies of a calamitic ester substituted aryolhydrazone liquid crystal (LC) system; N-[4-(4ʹ-decyloxy)benzoyloxy benzylidene]- Nʹ-[4ʹ-decyloxybenzoyl]hydrazine (DB2H) have been performed to investigate the molecular arrangement and intermolecular interaction environment in LC phase. X-ray diffraction study with the help of density functional theoretical study gives the information of molecular tilt angle in SmC layer. Prominent Raman signatures of crystal I → crystal II, crystal II → SmC and SmC → Isotropic phase transitions were identified in terms of changes in peak position and linewidth as well as Raman intensity. Analysis of Raman marker bands gives evidence of residual intermolecular hydrogen bonds between amide groups responsible for tilting arrangement in SmC phase. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Surface roughness plays a vital role in functional requirements of a component. Abrasive flow finishing (AFF) is an advanced finishing process used to achieve micro/nanolevel surface finish in complex geometries, internal inaccessible pathways made up of difficult to finish material, etc. In order to control the process and improve its performance, it is important to understand the mechanism of finishing. In this paper, an attempt has been made to model the forces generated during AFF process using the rheological properties of the viscoelastic medium used in the process. Secondly, by using the calculated forces, simulation of the final surface roughness profile of the workpiece has been presented. The simulated results are in good agreement with the experimental results. [ABSTRACT FROM AUTHOR]

This paper presents a complete position sensorless control scheme for permanent magnet brushless DC motors (PMBLDCMs) using back-EMF sensing method. The controller is designed in such a way that it provides smooth shifting from open-loop speed-up mode to back-EMF sensing mode at any speed, especially at very low speeds, i.e., less than 2% of the rated speed. The proposed scheme is a simple and cost effective implementation of back-EMF sensing method, which does not require any filtering or phase shift to generate commutation pulses. The proposed controller is designed and modeled for a PMBLDCM rated at 4600rpm, 310V and 2.2Nm torque and its performance is simulated in MATLAB/SIMULINK environment. The obtained simulation results are validated on a prototype developed in the lab using a digital signal processor (DSP) namely TI 2812 DSP in a wide range of speeds in position sensorless mode. [ABSTRACT FROM AUTHOR]

We developed a simple, sensitive, label-free and real time detection method for mercuric ions (Hg 2+ ) in water using liquid crystals (LCs). In this system, newly synthesized amphiphilic potassium N-methyl-N-dodecyldithiocarbamate (MeDTC) was doped in 4-cyano-4′-pentyl biphenyl (5CB) LC, which align LC molecules at aqueous interface and polar head group of the amphiphile acts as mecuric ion specific chelating ligand. When this sensor system was incubated in the aqueous solution containing Hg 2+ ions, a dark to bright transition of the image of LCs was observed. This was caused due to rapid and stable complex formation between dithiocarbamate chelating group of MeDTC with Hg 2+ ions at aqueous interface, which disrupted the orientation of LCs giving bright texture. The limit of detection of the system for aqueous Hg 2+ ion is 0.5 μM. This sensor did not respond to other metal ions like Pb 2+ , Cd 2+ , Cu 2+ , Zn 2+ , Na + , Mg 2+ and Ca 2+ , which are common environmental interference in water. We also demonstrated that this sensor is capable of detecting Hg 2+ ions in real water samples (tap water). The very simple and effective procedure reported here should facilitate the development of real time, portable and reliable LC based sensor for mercury pollution control. [ABSTRACT FROM AUTHOR]

Study of copper complex of creatinine and urea is very important in life science and medicine. In this paper, spectroscopic and structural study of a newly synthesized heteroligand complex of copper with creatinine and urea has been discussed. Structural studies have been carried out using DFT calculations and spectroscopic analyses were carried out by FT-IR, Raman, UV–vis absorption and fluorescence techniques. The copper complex of creatinine and the heteroligand complex were found to have much increased water solubility as compared to pure creatinine. The analysis of FT-IR and Raman spectra helps to understand the coordination properties of the two ligands and to determine the probable structure of the heteroligand complex. The LIBS spectra of the heteroligand complex reveal that the complex is free from other metal impurities. UV–visible absorption spectra and the fluorescence emission spectra of the aqueous solution of Cu–Crn–urea heteroligand complex at different solute concentrations have been analyzed and the complex is found to be rigid and stable in its monomeric form at very low concentrations. [ABSTRACT FROM AUTHOR]

A novel homologous series of N-[4-[4′-n-alkoxy)benzoyloxy-2-hydroxybenzylidene)-4-carbethoxy anilines, H2n+1CnOC6H4C(O)OC6H3(OH)C(H)˭NC6H4COOC2H5(n = 6, 8, 10, 12, 14, 16) and their copper(II) complexes have been synthesized. All these compounds have been characterized by suitable spectroscopic techniques. The mesomorphic properties of these compounds were investigated by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). The ligands exhibit wide range of enantiotropic smectic A and nematic phases as confirmed by their typical optical texture under polarizing microscope. The square planar copper(II) complexes of the ligands show only an isotropic phase at higher temperature and no mesogenic nature is observed. DFT calculations have been performed using GAUSSIAN-03 program at B3LYP level to obtain the stable electronic structure of the ligand with decyloxy chain length and its copper(II) complex. [ABSTRACT FROM AUTHOR]