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Water is a universal solvent and swelling agent that is widely used in wood industry in association with organic solvents and salts, whether for the fractionation of biomass and the production of bio-based synthons for the chemical industry, the application of sizing agents and painting for the paper industry or the incorporation of preservatives to enhance wood durability for the timber industry. The relevance of solvents and technical treatments used for wood-based products requires a proper identification of the specific role of each solvent on wood biopolymers to better understand and predict their influence on wood properties. In particular, wood impregnated with aqueous solutions of organic solvents has shown to give rise to greater swelling than that observed in pure water, described as "hyperswelling". To understand this phenomenon, the first step is to examine the existing interactions between wood microstructure and the different solvents present in these mixtures. This study is an attempt to bring to light the sorption behaviour of four different hardwoods in water–ethanol vapour mixtures containing increasing molar fractions of ethanol from 0 to 100%. Contrasted sorption behaviour in pure solvents was observed according to wood species having different biochemical compositions. This behaviour highlights the different affinities of ethanol and water for the macromolecules present in the wood microstructure. With mixed solvents, peculiar effects were confirmed in sorption behaviour of woods with lower mixed solvent uptake at high partial pressures compared to pure solvents. It is also shown that part of the sorbed ethanol molecules remains chemisorbed in the wood structures at the end of the desorption process. [ABSTRACT FROM AUTHOR]

Biologically inspired nanomaterials and nanotechnology have advanced in almost all scientific and technological research areas, including biomedical applications and agriculture. Nanomaterials hold immense potential for applications in biomedical and agricultural applications. By harnessing the natural capabilities of plants as sources of reducing and capping agents, the synthesis of nanomaterials becomes cost‐effective eco‐friendly, and yields biocompatible products. Here, we provide a comprehensive overview of various plant‐derived nanomaterials synthesized using different methods, highlighting their applications in biomedical and biological sciences, including bioimaging, biosensing, drug delivery, and therapeutics. Additionally, the impact of nanotechnology on precision agriculture is explored, showcasing recent advancements such as nanofertilizers, nanopesticides, nanobiosensors, and nanocarrier‐mediated delivery systems, which exhibit promising results. These recent developments underscore the transformative potential of nanotechnology in both biomedical and agriculture domains. [ABSTRACT FROM AUTHOR]

Jaundice is a yellow colouring of the skin, mucous membranes, and the conjunctival membrane surrounding the sclera. It is a clinical indication of underlying hepatocellular dysfunction, biliary obstruction, or anomalies in bilirubin metabolism. Kamala might be linked to jaundice based on shared traits. Ayurveda has been well known for treating liver disorders for centuries. In this case report, a 29-year-old male patient, visited the Kayachikitsa outpatient department with primary complaints of pricking pain in the abdomen, loss of appetite, yellow discolouration of urine, nausea, vomiting, generalised weakness, and constipation for 10 days. Based on clinical examination and Liver Function Tests (LFT), he was diagnosed with jaundice. The patient was effectively treated with Shodhan (bio-purification) with sadya virechan (purgation therapy) followed by medicinal treatment for 45 days. Within 7-8 days, there was a significant improvement in abdominal pain with mild tenderness, frequency of vomiting, complaints of anorexia, nausea, constipation, and yellow discolouration of urine, along with substantial improvement in liver function. After 45 days of Ayurvedic treatment, all symptoms and liver functions showed highly significant results. The treatment was given by considering the vitiation of Pitta and Rakta. It can be concluded that by implementing Ayurvedic treatment principles, liver function can be improved in cases of jaundice in a short duration without causing any adverse effects. [ABSTRACT FROM AUTHOR]

Autism, also known as Autism Spectrum Disorder (or ASD), is a neurological disorder. Its main symptoms include difficulty in verbal/non-verbal communication and rigid/repetitive behavior. These symptoms are often indistinguishable from a normal (control) individual due to which this disorder remains undiagnosed in early childhood, thus leading to a delayed treatment. Since the learning curve is steep during the initial years, an early diagnosis of autism would allow to make an early intervention, which in turn would positively affect the growth of an autistic child. Further, the traditional methods of autism diagnosis require multiple visits to a specialized doctor; however, this process is generally time-consuming. In this paper, we present a learning-based approach to automate autism diagnosis using simple and small action video clips of subjects. This task is particularly challenging because the amount of annotated data available is small, and the variations among samples from the two categories (ASD and control) are generally indistinguishable. This is also evident from poor performance of a baseline binary classifier on this task. To address this, we propose to adopt contrastive feature learning for the first time on this task and demonstrate a significant increase in the prediction accuracy. We further validate this by conducting thorough experimental analyses in both self-supervised and supervised setups on two publicly available datasets. We have also released our codes and pre-trained models for reproducibility. [ABSTRACT FROM AUTHOR]

Cancer is a condition where abnormal cells multiply uncontrollably and can invade nearby tissues. Only 30% of women with ovarian cancer can expect to live for more than 5 years, as 70% of cases are diagnosed at an advanced stage. Ovarian malignancies account for about 15 to 20% of genital malignancies. Surgical intervention and chemotherapy are conventional measures used to treat these conditions. However, due to the specific side effects of chemotherapy, there is a high demand for safer ayurvedic interventions. Hereby, the authors present, a 54-year-old female patient who was diagnosed with ovarian cancer and advised to undergo chemotherapy. After completing six cycles of chemotherapy, administered once every four weeks for six months, the patient experienced complaints of anorexia, nausea, vomiting, epigastric pain, and a burning sensation in the stomach and lower limbs. Despite taking antacids and other suggested medications by the oncologist, the symptoms did not subside. Therefore, the patient sought ayurvedic treatment. Shaman Ayurvedic Chikitsa (Jawahar Mohra Pisti, Keharva Pisti, Swarna Makshik, Mukta Pisti), Shatavari Ghrita, Turmeric Kwath, and Pathya Vihar were prescribed for three consecutive months. After 5-7 days, the patient noticed significant relief in the aforementioned symptoms and felt better. The frequency of vomiting, complaints of anorexia, and burning sensation were also significantly reduced. After three months of ayurvedic treatment, the functions of Apana Vayu, Samana Vayu, and Pachaka Pitta were normalised through appropriate treatment. The selected combination of ayurvedic medicines provided relief due to their Vata-Pitta Shamak, Sheeta guna, and Pittahara properties, which alleviated the burning sensation. In present case report, the aforementioned ayurvedic prescription significantly reduced the adverse effects of chemotherapy and radiotherapy due to its Vata-Pitta Shamak and Pittahara properties. [ABSTRACT FROM AUTHOR]

In this paper, the study of mixed radio frequency (RF)/ free space optical (FSO) communication decode and forward (DF) two way relaying (TWR) has been presented. In fact, it has been considered that multiple relays are present out of which the best operational relay is selected as per the partial relay selection (PRS) methodology in the presence of outdated channel state information (CSI). Importantly, the relay nodes are assumed to operate in the presence of in phase (I) quadrature phase (Q) imbalance (IQI). The atmospheric turbulence on the FSO link has been modeled using the Malaga distribution with pointing errors. In addition to this, the impact of type of optical demodulation has been considered in the analysis. For the system model, outage probability expression has been derived in terms of Meijer-G and Fox's H-functions. In addition to this, for the TWR system, the outage probability expressions have been modified to present asymptotic results in terms of elementary functions. The numerical analysis of the research work suggests that the overall mixed RF/FSO DF TWR system is impacted by the image rejection ratio (IRR) due to IQI, correlation between outdated CSI, atmospheric turbulence, pointing error and type of optical demodulation in addition to the amount of fading on the RF link. [ABSTRACT FROM AUTHOR]

Avascular Necrosis (AVN) is a pathological condition characterised by a reduction in the blood supply to the subchondral bone, leading to the degenerative condition of the bone, marked by the death of cellular components of the bone. It is also known as osteonecrosis. The epiphysis of long bones at weight-bearing joints is typically affected. All of these conditions have a poor prognosis. In Ayurveda, it corresponds to Asthivahastrotodushtivikara (musculoskeletal disorder) as there is kshaya (necrosis) of asthi (bone) and Majja (bone marrow) dhatu (major structural components of the body). In modern medicine, AVN is managed by the use of corticosteroids and many surgical procedures such as drilling, insertion of prosthetics, or bone grafts. Therefore, Ayurveda provides a conservative line of treatment based on the principle of Asthi-majjagatkashaya (decalcification of bone) caused by abhighatajanyavataprakopa (trauma). A case of AVN with the right femoral head was treated with shaman (oral medications), Sodhana (bio-purification), and bruhmana (rejuvenation) procedures. The therapy provided significant improvements in pain and range of movement of the hip joint, based on the patient's signs and symptoms before and after treatment. Conservative treatment can give outstanding results, improve the quality of life, halt disease progression, and help manage AVN by tissue regeneration without harmful effects. [ABSTRACT FROM AUTHOR]

The metabolic, physiological, and behavioral processes in most of the living organisms exhibit an approximate 24-h rhythmic, self-sustained circadian (L. circa = about, dies = day) oscillations. These oscillations, apart from passively persisting in synchrony with external cues, exist in their absence as well, conferring adaptive advantage by following environmental cycle (extrinsic adaptation) and physiological harmony (intrinsic advantage), and tackling the adverse seasonal changes. Interestingly, these circadian perturbations generated at cellular level as rhythms are pretty much hierarchically similar across unicellular organisms to complex mammals. The biological clocks (master clock along with peripheral clocks) are able to influence biological fitness, life-history traits, physiology and behavior of organism. Given that the circadian clocks influence various biological processes, its evolutionary significance remained the subject of several laboratory studies with the view that imposing artificial selection for various clock properties such as phase, period, etc., might lead to the co-evolution of associated other clock-controlled evolutionary traits. In this review, we have presented key hypotheses pertaining to circadian rhythms, where by its presence to the owner can confer adaptive advantage intrinsically and extrinsically and enable endogenous clock to perform better in synchrony with the environment. [ABSTRACT FROM AUTHOR]

Drosophila melanogaster has been used in Diet Restriction (DR) studies for a few decades now, due to easy diet implementation and its short lifespan. Since the concentration of protein determines the trade-offs between lifespan and fecundity, it is important to understand the level of protein and the extent of its influence on lifespan, fecundity and activity of fruit flies. In this study, we intend to assess the effect of a series of protein restricted diets from age 1 day of the adult fly on these traits to understand the possible variations in trade-off across tested diets. We found that lifespan under different protein concentrations remains unaltered, even though protein restricted diets exerted an age-specific influence on fecundity. Interestingly, there was no difference in lifetime activity of the flies in most of the tested protein restricted (PR) diets, even though a sex-dependent influence of protein concentrations was observed. Additionally, we report that not all concentrations of PR diet increase activity, thereby suggesting that the correlation between lifespan and the lifetime activity can be challenged under protein-restricted condition. Therefore, the PR does not need to exert its effect on lifespan and fecundity only but can also influence activity levels of the flies, thereby emphasizing the role of nutrient allotment between lifespan, fecundity and activity. [ABSTRACT FROM AUTHOR]

Statistical models provide a powerful and useful class of approximations for calculating reaction rates by bypassing the need for detailed, and often difficult, dynamical considerations. Such approaches invariably invoke specific assumptions about the extent of intramolecular vibrational energy flow in the system. However, the nature of the transition to the statistical regime as a function of the molecular parameters is far from being completely understood. Here, we use tools from nonlinear dynamics to study the transition to statisticality in a model unimolecular reaction by explicitly visualizing the high dimensional classical phase space. We identify generic features in the phase space involving the intersection of two or more independent anharmonic resonances and show that the presence of correlated, but chaotic, intramolecular dynamics near such junctions leads to nonstatisticality. Interestingly, akin to the stability of asteroids in the Solar System, molecules can stay protected from dissociation at the junctions for several picoseconds due to the phenomenon of stable chaos. Statistical models are useful to approximate reaction rates, bypassing the need for detailed dynamical considerations. Here the authors use nonlinear dynamics to visualize the high dimensional phase space and identify the dynamical origins of nonstatisticality in unimolecular reactions. [ABSTRACT FROM AUTHOR]

The stability of perovskite solar cells is a key issue for industrial development. One reason for this is the volatile organic methylammonium (MA) cation, which is prone to degas under elevated temperatures from the perovskite. At the same time, small amounts of MA are used for practically all highest performing solar cells. These compositions have also shown relatively promising stabilities. This raises the question of MA stability with respect to different, application-dependent stability requirements. Interestingly, MA stability was mainly studied on thin films that differ from full devices or with architectures which are also prone to degrade. Therefore, the degradation behavior on complete MA containing devices with a relatively stable architecture is required to quantify the long-term stability of MA. This enables to determine at which timescales MA is unstable and which role it can play in future compositions. If MA is indeed unstable at much longer timescales than previously recorded, it also indicates that more severe degradation pathways are currently underappreciated. Here, "weakest link" MAPbI 3 solar cells show stability where devices retained 100% of their initial efficiency over 1000 h of aging under constant illumination and maximum power point tracking at 20 °C. At elevated temperatures of 50 and 65 °C, the devices retained 100% and 90% of their initial efficiency after 500 h of illumination, respectively. Impressively, at 95 °C the MAPbI 3 device retained 85% of its initial efficiency after 500 h under constant illumination, which is some of the best stability data reported to date for MA. Thus, MA-containing devices require further studying. Nevertheless to achieve the necessary industrial lifetimes of more than 25 years, the complete removal of MA is a sensible precaution to systematically avoid any long-term risk factors. [ABSTRACT FROM AUTHOR]

• The ruthenium doped mesoporous TiO 2 synthesized via surface treatment. • Ruthenium doping enhance the optical and electronic properties of mesoporous TiO 2. • The efficiency and stability of mesoporous TiO 2 perovskite solar cell enhanced. • PSCs with 0.1 M Ru-TiO 2 show higher efficiency with negligible hysteresis. The electron transporting layer (ETL) plays a vital role in the power conversion efficiency (PCE) of perovskite solar cells (PSCs). We have demonstrated the synthesis of ruthenium doped mesoporous TiO 2 (Ru-TiO 2) and their utility as ETLs for PSCs. The doping effects of Ru4+ on the electronic and photovoltaic properties of mesoporous TiO 2 (mp-TiO 2) have been investigated as well. The highest PCE of 18.94% was obtained with 0.1 M Ru-TiO 2 PSCs exhibiting an open circuit voltage (V OC) of 1.128 V, current density (J SC) of 22.55 mA cm−2, and fill factor (FF) of 76.55%, whereas the conventional mesoporous PSCs showed PCE = 16.80%, V OC = 1.095 V, J SC = 21.50 mA cm−2, and FF = 70.01%. Note that the 0.1 M Ru-TiO 2 device shows high PCE with negligible hysteresis index, high reproducibility and more stability as compared to conventional mesoporous PSCs. [ABSTRACT FROM AUTHOR]

Abstract: Interfacial studies and band alignment engineering on the electron transport layer (ETL) play a key role for fabrication of high‐performance perovskite solar cells (PSCs). Here, an amorphous layer of SnO2 (a‐SnO2) between the TiO2 ETL and the perovskite absorber is inserted and the charge transport properties of the device are studied. The double‐layer structure of TiO2 compact layer (c‐TiO2) and a‐SnO2 ETL leads to modification of interface energetics, resulting in improved charge collection and decreased carrier recombination in PSCs. The optimized device based on a‐SnO2/c‐TiO2 ETL shows a maximum power conversion efficiency (PCE) of 21.4% as compared to 19.33% for c‐TiO2 based device. Moreover, the modified device demonstrates a maximum open‐circuit voltage (Voc) of 1.223 V with 387 mV loss in potential, which is among the highest reported value for PSCs with negligible hysteresis. The stability results show that the device on c‐TiO2/a‐SnO2 retains about 91% of its initial PCE value after 500 h light illumination, which is higher than pure c‐TiO2 (67%) based devices. Interestingly, using a‐SnO2/c‐TiO2 ETL the PCE loss was only 10% of initial value under continuous UV light illumination after 30 h, which is higher than that of c‐TiO2 based device (28% PCE loss). [ABSTRACT FROM AUTHOR]

Abstract: The electronic processes occurring within the perovskite solar cells (PSCs) are strongly influenced by the nature of the organic A cations present within the inorganic framework. In this study, the impact of FA (CH(NH2)2+) and Cs+ cations on the intrinsic and interfacial properties in the FAPbBr3 and CsPbBr3 PSCs is investigated. The analysis of current density (JSC) and photovoltage (VOC) as a function of illumination intensity establishes that the interfacial charge transport is more rapid in FAPbBr3 devices. Small perturbation measurements including intensity modulated photocurrent and photovoltage spectroscopy are applied to explore the resistive and capacitive elements. Furthermore, electrochemical impedance spectroscopy measurements are found to correlate well with the photovoltaic characteristics of FAPbBr3 and CsPbBr3 PSCs. Overall, the in‐depth analysis of various phenomena occurring within the bromide PSCs allows to underline the working principle, which provides a key to optimize the device performance. The present protocol is not only valid for PSCs but can also be extended to devices based on alternative light harvesters. [ABSTRACT FROM AUTHOR]

This paper presents an outlook to enhance the productivity of a basin type double slope multi–wick solar still by introducing the wicks. The experimental data for different months are presented, and analyzed the effect of climatic and operational parameters on the performance of modified basin type double slope multi–wick solar still (MBDSMWSS). The study has been conducted at Motilal Nehru National Institute of Technology Allahabad (MNNIT Allahabad), Uttar Pradesh (U.P.), India. A significant increase in the heat input, yield, and overall thermal efficiency have been obtained. In the instantaneous efficiency equation, the yield output and the heat input to the solar still is modified as input from both the glass covers and transparent walls are considered for the modified solar still. The result shows that, the maximum yield is obtained as 9012 ml/day (4.50 l/m 2 day) for black cotton wick in comparison to 7040 ml/day (3.52 l/m 2 day) for the jute wick at 2 cm water depth in MBDSMWSS. Also, for same basin condition, the overall thermal efficiency of MBDSMWSS with the jute and black cotton wicks are 20.94% and 23.03%, respectively. [ABSTRACT FROM AUTHOR]

Theoretical suggestion indicated the substantial improvement of solar cells by using periodic structures. Yet, the promise has not been practically realized due to the lack of electrical analyses of periodical light-absorbing structure. Here, we report the record high-efficiency of 16.9% for periodically patterned silicon (Si) solar cells. Periodic Si micro-pillars were fabricated for large-scale solar cells. The Si pillars with a height of about 5 μm provided significantly enlarged light-active surface, which improved the photo-generated carrier collection efficiency. From optical aspects, the pillar structures reduced light reflection and hence effectively drove more photons into the absorber layer. Additionally, the enhanced pillar-structured Si surface definitely contributed to reduce an electrical resistance of a solar cell. We demonstrated that the surficial enhanced Si design could be a promising approach for high-efficient solar cell applications. We may suggest a route for the optimum electrical designs of periodic structured solar cells. [ABSTRACT FROM AUTHOR]

In this article, electrochemical properties of CuO nanostructures based dopamine (DA) sensor was investigated. The morphology, structure, optical, and compositional properties of the CuO nanostructures were characterized by using SEM, XRD, UV-Vis, and XPS techniques. The electrochemical properties were investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. The CV results indicate that biosensors based on CuO nanostructures exhibit a high selectivity and sensitivity of 0.1975 μA μM-1 toward DA and effectively avoids the interference of ascorbic acid (AA) and uric acid (UA). The obtained EIS spectra for CuO sensors were analysed using an electrical equivalent circuit to understand the bulk and surface response via the capacitive and resistive parameters. The EIS measurement also leads to the direct determination of parameters like series resistance and ion diffusion phenomena at electrode-electrolyte interface. The experimental CV and EIS results along with their analysis will have a significant impact on understanding the mechanism of high sensitivity and selectivity performance of CuO based sensors. This study may also lay the basis for efficient characterization of biosensors by coupling both the CV and EIS characterization techniques. [ABSTRACT FROM AUTHOR]

Solar energy generation and utilization is dominated by silicon based solar photovoltaic technology, which has a market share of 80–90% of the solar photovoltaic industry worldwide. The performance indicating parameters of silicon solar cells include power conversion efficiency, series and shunt resistance, ideality factor and built-in potential. These parameters are mostly characterized by DC techniques, which is limited by its insufficiency to identify other important parameters such as interfacial diffusion and transition capacitance and resistive and capacitive components of p-p + interface of a silicon solar cell. Impedance spectroscopy is considered to be one of the most promising techniques for the characterization of abovementioned performance limiting parameters of a solar cell. In order to address the decoupling of various physical processes associated with different interfaces of a solar cell, quantitative analysis of the impedance spectroscopic data is required. An appropriate mathematical model is frequently used to correlate with the physical performance limiting parameters. This review presents a complete overview of the required mathematical models to analyse impedance spectroscopic data for interfacial processes of silicon solar cell. [ABSTRACT FROM AUTHOR]

Perfluorooctane sulfonic acid (PFOS) exposure during pregnancy induces hypertension with decreased vasodilatory angiotensin type-2 receptor (AT2R) expression and impaired vascular reactivity and fetal weights. We hypothesized that AT2R activation restores the AT1R/AT2R balance and reverses gestational hypertension by improving vascular mechanisms. Pregnant Sprague-Dawley rats were exposed to PFOS through drinking water (50 μg/mL) from gestation day (GD) 4–20. Controls received drinking water with no detectable PFOS. Control and PFOS-exposed rats were treated with AT2R agonist Compound 21 (C21; 0.3 mg/kg/day, SC) from GD 15–20. In PFOS dams, blood pressure was higher, blood flow in the uterine artery was reduced, and C21 reversed these to control levels. C21 mitigated the heightened contraction response to Ang II and enhanced endothelium-dependent vasorelaxation in uterine arteries of PFOS dams. The observed vascular effects of C21 were correlated with reduced AT1R levels and increased AT2R and eNOS protein levels. C21 also increased plasma bradykinin production in PFOS dams and attenuated the fetoplacental growth restriction. These data suggest that C21 improves the PFOS-induced maternal vascular dysfunction and blood flow to the fetoplacental unit, providing preclinical evidence to support that AT2R activation may be an important target for preventing or treating PFOS-induced adverse maternal and fetal outcomes. [ABSTRACT FROM AUTHOR]

Distance measures are part and parcel of many computer vision algorithms. The underlying assumption in all existing distance measures is that feature elements are independent and identically distributed. However, in real-world settings, data generally originate from heterogeneous sources even if they do possess a common data-generating mechanism. Since these sources are not identically distributed by necessity, the assumption of identical distribution is inappropriate. Here, we use statistical analysis to show that feature elements of local image descriptors are indeed non-identically distributed. To test the effect of omitting the unified distribution assumption, we created a new distance measure called the Poisson-Binomial radius (PBR). PBR is a bin-to-bin distance which accounts for the dispersion of bin-to-bin information. PBR's performance was evaluated on twelve benchmark data sets covering six different classification and recognition applications: texture, material, leaf, scene, ear biometrics and category-level image classification. Results from these experiments demonstrate that PBR outperforms state-of-the-art distance measures for most of the data sets and achieves comparable performance on the rest, suggesting that accounting for different distributions in distance measures can improve performance in classification and recognition tasks. [ABSTRACT FROM AUTHOR]

The present work describes a method for the development of an efficient silver nanowire (AgNWs) embedded indium tin oxide (ITO) based silicon heterojunction solar cell. The working mechanism of the heterojunction solar cell is studied by using the current-voltage (J-V) and Impedance spectroscopy (IS) techniques. The charge transfer mechanism and recombination process of the solar cell were explained by resistance, capacitance and ideality factor derived from both these techniques. A relatively high efficiency has been achieved for AgNWs embedded ITO-Si heterojunction solar cell in which AgNWs network acts as a transparent buried contact. This study also provides a new architecture for various heterojunction solar cells with a simple route of fabrication. [ABSTRACT FROM AUTHOR]

Chronic inflammation and oxidative stress play important role in development of hypertension. Recently, we have reported novel fluorophenyl benzimidazole (FPD) for vasorelaxation and antihypertensive activity in SHRs. The present study envisaged the anti-inflammatory, anti-oxidant and cardio-protective properties of FPD in L-NAME model of hypertension with special emphasis on reversal of vascular remodeling, gene expression and restoration of hemodynamic. Antihypertensive activity of FPD was evaluated in L-NAME treated Wistar rats, and the parameters studied were anti-inflammatory activity, histomorphological changes, gene expression profile and anti-oxidant properties. FPD at 50 and 100 mg kg−1 once daily for 15 days significantly reduced SBP, DBP and MAP in L-NAME treated rats and the values were well comparable to vehicle control group. Further, FPD treatment showed a significant increase in hepatic GSH content, SOD, catalase activity, decreased MDA level and restoration of pro and anti-inflammatory cytokine levels. The mRNA expression profile of genes associated with regulation of vascular tone, remodeling and inflammation showed a significant level of alteration by chronic L-NAME treatment and was dose-dependently restored upon treatment with FPD. Further, FPD treatment restored serum lipid profile, CK, CK-MB and LDH level and also reversed the histomorphological changes like intimal wall thickening, hyperplasia of cardiomyocytes and ventricular wall thickening. Taken together, FPD produced potent antihypertensive activity in L-NAME model through vasorelaxation, anti-oxidative and anti-inflammatory properties leading to restoration of serum lipid profile, cardiac biomarker, expression profile of target genes and reversal of histomorphological changes. [ABSTRACT FROM AUTHOR]

In the present article, the direct current and alternating current characterization techniques are employed to investigate the losses during interfacial charge transport in dye-sensitized solar cell (area: 3.78 cm 2 ) having a power conversion efficiency of 4.32%. The analysis of current–voltage characteristics depicts that the loss in photocurrent density is about 1–1.5% at low forward bias, ∼8% at knee voltage and ∼79% at open circuit voltage. The electrochemical impedance spectroscopy measurement leads to the direct determination of recombination resistance, chemical capacitance, charge transport resistance and double layer capacitance. The current–voltage characteristics obtained from the impedance parameters allows separating the contributions of different resistive processes on the overall conversion efficiency. The experimental results along with the analytical model provide an insight into the electric power loss mechanism, which is useful for analyzing performance of other upcoming devices with a similar working mechanism like perovskite sensitized solar cells. [ABSTRACT FROM AUTHOR]

This work describes the role of graphene in charge transport and diffusion mechanism at TiO 2 /graphene electrode–electrolyte interface. To explore the mechanism, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used. The CV results depict that TiO 2 and TiO 2 /graphene electrodes behave differently in terms of charge transport and ion adsorption under the steady state conditions. The performance of TiO 2 electrode–electrolyte interface is mainly limited by the charge transport and pseudo-capacitive effects while the response of TiO 2 /graphene electrode–electrolyte interface is mainly dominated by the double layer capacitive effects. The EIS measurement leads to the direct determination of broad range of parameters, i.e. series resistance, charge transport, rate capability and ion diffusion. The experimental results and their analysis will have a significant impact on understanding the role of graphene in the electrochemical response of an electrode–electrolyte interface. [ABSTRACT FROM AUTHOR]

A perovskite heterojunction solar cell is fabricated with architecture of hole transport material (HTM) free discrete electrode. The morphological, structural and optical properties are studied by FESEM, XRD and UV–Vis spectrophotometry techniques. A single diode model has been used to investigate the cell characteristics. The interface between TiO 2 and CH 3 NH 3 PbI 3 layer is found analogous to Schottky diode that acts as a heterojunction for excitation and dissociation of charge carriers due to the existence of an internal electric field at the junction. The SCAPS simulation is done to explore the role of interface defects and band offsets. Device simulation has shown an improvement of 16%, 6% and 25% in V OC , FF and η respectively with incorporation of the HTM layer in device structure. [ABSTRACT FROM AUTHOR]

This article focuses on the identification of key features that are responsible for the discrepancies in the performance of silicon solar cells fabricated on multicrystalline silicon under the identical conditions. In an experimental approach, direct current (DC) measurement coupled with alternating current (AC) characterisation technique has been employed. The scanning electron microscope analysis reveals an average grain size of few micrometres for all the solar cells and the top surface of least efficient solar cell contains the impurity precipitates with deep cone shaped holes or pits. The DC measurement reveals that the photocurrent density loss follows an exponential behaviour with respect to the current–voltage characteristics for all the solar cells. The analysis of − dV / dJ versus ( J SC − J ) −1 plot and the variation of ideality factor with junction voltage demonstrate that the higher resistive and recombination losses dominate the performance of least efficient solar cell. Impedance Spectroscopy (IS) technique is used to quantify and decouple the various photovoltaic parameters associated with the different physical processes. A lower value of shunt resistance and minority carrier lifetime along with the higher value of series resistance contribute to the higher resistive loss and surface recombination. The experimental results along with the analytical model provide an insight into the loss mechanisms and the use of a simple tool that can be integrated with the conventional photovoltaic testing. [ABSTRACT FROM AUTHOR]

Gene-environment interactions (G × E) have attracted considerable research interest in the past owing to their scientific and public health implications, but powerful statistical methods are required to successfully track down G × E, particularly at a genome-wide level. Previously, a case-only (CO) design has been proposed as a means to identify G × E with greater efficiency than traditional case-control or cohort studies. However, as with genotype-phenotype association studies themselves, hidden population stratification (PS) can impact the validity of G × E studies using a CO design. Since this problem has been subject to little research to date, we used comprehensive simulation to systematically assess the type I error rate, power and effect size bias of CO studies of G × E in the presence of PS. Three types of PS were considered, namely genetic-only (PS), environment-only (PS), and joint genetic and environmental stratification (PS). Our results reveal that the type I error rate of an unadjusted Wald test, appropriate for the CO design, would be close to its nominal level (0.05 in our study) as long as PS involves only one interaction partner (i.e., either PS or PS). In contrast, if the study population is stratified with respect to both G and E (i.e., if there is PS), then the type I error rate is seriously inflated and estimates of the underlying G × E interaction are biased. Comparison of CO to a family-based case-parents design confirmed that the latter is more robust against PS, as expected. However, case-parent trios may be particularly unsuitable for G × E studies in view of the fact that they require genotype data from parents and that many diseases with an environmental component are likely to be of late onset. An alternative approach to adjusting for PS is principal component analysis (PCA), which has been widely used for this very purpose in past genome-wide association studies (GWAS). However, resolving genetic PS properly by PCA requires genetic data at the population level, the availability of which would conflict with the basic idea of the CO design. Therefore, we explored three modified Wald test statistics, inspired by the genomic control (GC) approach to GWAS, as an alternative means to allow for PS. The modified statistics were benchmarked against a stratified Wald test assuming known population affiliation, which should provide maximum power under PS. Our results confirm that GC is capable of successfully and efficiently correcting the PS-induced inflation of the type I error rate in CO studies of G × E. [ABSTRACT FROM AUTHOR]

Circadian clocks time developmental stages of fruit flies Drosophila melanogaster, while light/dark (LD) cycles delimit emergence of adults, conceding only during the 'allowed gate.' Previous studies have revealed that time-to-emergence can be altered by mutations in the core clock gene period ( per), or by altering the length of LD cycles. Since this evidence came from studies on genetically manipulated flies, or on flies maintained under LD cycles with limited range of periods, inferences that can be drawn are limited. Moreover, the extent of shortening or lengthening of time-to-emergence remains yet unknown. In order to pursue this further, we assayed time-to-emergence of D. melanogaster under 12 different LD cycles as well as in constant light (LL) and constant dark conditions (DD). Time-to-emergence in flies occurred earlier under LL than in LD cycles and DD. Among the LD cycles, time-to-emergence occurred earlier under T4- T8, followed by T36- T48, and then T12- T32, suggesting that egg-to-emergence duration in flies becomes shorter when the length of LD cycles deviates from 24 h, bearing a strong positive and a marginally negative correlation with day length, for values shorter and longer than 24 h, respectively. These results suggest that the extent of mismatch between the period of circadian clocks and environmental cycles determines the time-to-emergence in Drosophila. [ABSTRACT FROM AUTHOR]

Method We report management of a failed revascularization/revitalization case, which could be due to inadequate removal of biofilm and bacteria in dentinal tubules. The use of an apical matrix barrier in form of a platelet-rich fibrin ( PRF) membrane for stabilization of MTA in root end apexification procedure is described. The canal was cleansed of old MTA present in the cervical third using H files, irrigated using saline and finally irrigated with 2.5% Na OCl and saline. To obtain canal disinfection, calcium hydroxide paste was temporized in the canal. In subsequent appointments, PRF was placed at the root tip followed by 5-mm apical plug with mineral trioxide aggregate. One week later, the root canal was obturated with thermoplasticized gutta-percha. A 6-month and a 2-year follow ups showed reduction of periapical radiolucency and adequately functional tooth. Results One-visit apexification techniques provide an alternative treatment for failed revascularization cases. Follow up confirmed complete healing periradicularly. Conclusion Apexification in one step using an apical barrier of PRF and a plug of MTA can be considered a predictable treatment and may be an alternative to long-term revascularization failures. [ABSTRACT FROM AUTHOR]

The present work reports an experimental study for the direct determination of broad range of performance indicating parameters of polycrystalline silicon solar cell by using direct current (DC) and alternating current (AC) characterization techniques. The DC characterization technique is employed to obtain the characteristic features of solar cell like fill factor, efficiency, series resistance and ideality factor. The AC characterization technique provides resolved electrical response of the resistances and capacitances of p–p + (back surface field) and n + –p junctions, series resistance of the solar cell as well as the lifetime of minority charge carriers. The current density–voltage ( J – V ) characteristics demonstrate the existence of non-linear shunt paths and higher charge recombination for a less efficient polycrystalline silicon solar cell. The impedance spectroscopy results reveal that a low fill factor observed for less efficient silicon solar cell is due to the hindrance of charge carriers in active layer and low Fermi level degeneracy at Aluminium/Silicon (Al/Si) interface. The obtained DC and AC parameters and their underlying mechanisms are also examined using the proposed theoretical model. The results presented here demonstrate that the DC technique coupled with AC characterization technique can be quantitatively utilized for the investigation of unexplored fundamental and applied aspects of silicon solar cells. [ABSTRACT FROM AUTHOR]

The present article reports an insight into the interplay between enhanced charge storage and charge transfer mechanism at electrode–electrolyte interface having different electrode morphology. The DC techniques like cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) are employed to obtain the interfacial capacitance and resistance, Faradaic features and charge retention ratio of the electrode–electrolyte interface as a function of applied bias. The porous nanorod morphology of copper doped polyaniline (PANI) delivered a maximum interfacial capacitance of 283 mF/cm 2 at 0.5 mA/cm 2 with a rate capability of 39%. On the contrary, the compact granular morphology of copper doped PANI delivered the maximum interfacial capacitance of 3.01 mF/cm 2 at 0.5 mA/cm 2 with a rate capability of 88%. AC technique like Electrochemical Impedance Spectroscopy (EIS) leads to the straight forward determination of charge transfer resistance, double layer capacitance, Warburg coefficient, interfacial capacitance and resistance, and series resistance of the electrode–electrolyte interface. [ABSTRACT FROM AUTHOR]

Commercially available polycrystalline silicon solar cells have been studied under varying illumination conditions to evaluate their application in low-concentration photovoltaic systems. The present work explores a detailed analytical framework for determining a broad range of performance indicating parameters for polycrystalline silicon solar cells by using the impedance spectroscopy (IS) technique. The IS measurements show that the diffusion capacitance varies from 1×10 −7 to 5×10 −7 F/cm 2 and diffusion resistance from 0.5 to 770 Ω-cm 2 with the applied bias. The IS measurements also indicated that the effective lifetime of charge carriers decreases with increasing illumination. This study confirms that commercially available polycrystalline silicon solar cells can work satisfactorily under low concentration (<3.5 suns). [ABSTRACT FROM AUTHOR]

This paper reports plasmon-enhanced light transmission through the Ag nanoparticle-coupled graphene thin-film deposited on fluorine-doped tin oxide (FTO) glass substrates. An experimental set-up is developed to quantify the photon enhancement due to metal nanoparticle-embedded graphene layer. The results show that a specific distribution of graphene nanosheets over Ag nanoparticle-deposited FTO glass can trap maximum normally incident light for photovoltaic applications. An enhancement of 6.35 % in the current density of silicon solar cell (kept under Ag-coated FTO glass) is observed for 30-μL graphene dispersion deposited on the FTO/Ag (3 nm). The results indicate the possibility of minimizing the reflection of incident radiation by combining plasmonic oscillations of metal nanoparticles with graphene plasmonics, which can be useful for optoelectronic devices, radiation sensors, and various types of photovoltaic cells. [ABSTRACT FROM AUTHOR]

Gene-environment ( G × E) interactions have been invoked to account, at least in part, for the gap between the known heritability of common human diseases and the phenotypic variation hitherto explained by genetic variants. Noteworthy in this context, a case-only (CO) design has been proposed in the past as a means to detect G × E interactions possibly more efficiently than by using classical case-control and cohort designs. So far, however, most CO studies have followed a candidate (or single) gene approach, and the genome-wide utility of the CO design is still more or less unknown. In particular, the way in which linkage disequilibrium (LD) impacts upon the chance to detect G × E interaction through the analysis of proxy markers has not been studied in much detail before. Therefore, we systematically assessed the power to indirectly detect a given G × E interaction through exploiting LD in a CO design. Our simulations revealed a strong relationship between LD and detection power that was subsequently validated in a real colorectal cancer data set. [ABSTRACT FROM AUTHOR]

This article compares and describes the photovoltaic performance of dye-sensitized solar cell (DSSC) consisting of platinum (Pt) and graphene-coupled-platinum based counter electrodes (CE). The power conversion efficiency of DSSC could be enhanced by 36% with multi-layer graphene flakes (MGF)/Pt CE as compared to Pt CE. Electrochemical impedance spectroscopy and cyclic voltammetry analysis show that DSSC with an MGF/Pt CE exhibits a higher electro-catalytic activity with lower series resistance. Two-diode model has been used to extract the recombination governing and the performance indicating parameters of a DSSC. An enhancement of ≈76% in short-circuit current of MGF/CE based DSSC, as compared to Pt CE, could be attributed to optical and catalytic properties of graphene. This study provides an insight into electronic transport mechanism of DSSC, which changes under the influence of highly catalytic materials such as graphene. [ABSTRACT FROM AUTHOR]

This study investigates the steady-state current–voltage characteristics, electronic and ionic processes and dynamic response of a TiO 2 nanoparticle based dye-sensitized solar cell (DSSC) using impedance spectroscopy and current–voltage measurements. A dye-sensitized solar cell is fabricated with 12.26 μm thick TiO 2 layer, having power conversion efficiency of 2.9% under AM1.5 spectrum with photo-generated current density ( J SC ) of 7.2 mA cm −2 and open-circuit voltage ( V OC ) of 672 mV. The observed electrochemical phenomenon at the TiO 2 –electrolyte interface, in diffusion of electrolyte and in charge transfer at the counter electrode is mathematically modeled using alternating current (AC) electrical equivalent circuit. The effect of temperature and illumination on the steady state and dynamic parameters of dye-sensitized solar cells is also studied. The dynamic resistance of DSSC decreases from 440.7 Ω to 78.6 Ω with increase in illumination level from 20 mW cm −2 to 100 mW cm −2 . [ABSTRACT FROM AUTHOR]

Highlights: [•] Low concentration photovoltaic (LCPV) system is designed and developed. [•] Commercially available crystalline silicon solar PV cells used under concentration. [•] Dynamic behavior of LCPV system is modeled and estimated. [•] Real-time analysis of LCPV system is presented. [Copyright &y& Elsevier]

Novel naphthoquinone, 2-benzyllawsone (LT-9) was evaluated against vascular hyporeactivity and sepsis in cecal ligation and puncture (CLP) model in mice in view of its preliminary antibacterial and anti-inflammatory properties and to explore whether pretreatment with the molecule could restore vascular tone and contractile response to norepinephrine. Evaluation of LT-9 against vascular hyporeactivity, hypotension, and sepsis-related inflammation and infection was carried out in the CLP model in Swiss albino mice and aortic smooth muscle cells in vitro. LT-9 showed potent reversal of the vascular hyporeactivity in CLP mice aorta. The increased contraction response to norepinephrine in CLP mouse aorta by LT-9 was mediated by opening of L-type voltage-dependent calcium channels (VDCC) verified by ex vivo experiment where LT-9 enhanced contraction response to CaCl 2 in the aorta while abolishing the contraction response of known VDCC opener Bay K8644. LT-9 in aortic smooth muscle cells showed Fluo-4 mediated increase in calcium fluorescence. Oral administration of LT-9 at 50 and 100 mg kg−1 day−1 for 15 days significantly enhanced the mean survival time, improved hemodynamic and Electrocardiogram (ECG) profile, and aortic tissue reactivity in CLP mice. Further, LT-9 significantly reversed the perturbation of the expression profile of inflammatory cytokines, reduced the splenic microbial load, and was well tolerated in oral toxicity. LT-9 showed potent biological activity against sepsis and was found to be well tolerated in the toxicity study in Swiss albino mice and showed promise for the benzyllawsone class of molecules against sepsis for the development of novel pharmacophore. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Circadian clocks have been postulated to regulate development time in several species of insects including fruit flies Drosophila melanogaster. Previously we have reported that selection for faster pre-adult development reduces development time (by ~19 h or ~11%) and clock period (by ~0.5 h), suggesting a role of circadian clocks in the regulation of development time in D. melanogaster. We reasoned that these faster developing populations could serve as a model to examine stage-specific interaction of circadian clocks and developmental events with the environmental light/dark (LD) conditions. We assayed the duration of three pre-adult stages in the faster developing (FD) and control (BD) populations under a variety of light regimes that are known to modulate circadian clocks and pre-adult development time of Drosophila to examine the role of circadian clocks in the timing of preadult developmental stages. Results We find that the duration of pre-adult stages was smaller under constant light (LL) and short period light (L)/dark (D) cycles (L:D = 10:10 h; T20) compared to the standard 24 h day (L:D = 12:12 h; T24), long LD cycles (L:D = 14:14 h; T28) and constant darkness (DD). The difference in the duration of pre-adult stages between the FD and BD populations was significantly smaller under the three LD cycles and LL compared to DD, possibly due to the fact that clocks of both FD and BD flies are driven at the same pace in the three LD regimes owing to circadian entrainment, or are rendered dysfunctional under LL. Conclusions These results suggest that interaction between light regimes and circadian clocks regulate the duration of pre-adult developmental stages in fruit flies D. melanogaster. [ABSTRACT FROM AUTHOR]

Abstract: Previously we have reported that selection for faster pre-adult development in fruit flies speeded-up development by ~29-h and shortened the clock period (τ) by ~0.5h, which suggests that development time and τ are correlated. Since it is known that τ is altered following exposure to light/dark (LD) cycles, we asked whether this correlation persists in the faster developing (FD) and control (BD) flies by examining the τ of the activity/rest rhythm and its difference between the two stocks following exposure to a variety of cyclic conditions. We assayed the activity/rest behavior of FD and BD flies under DD, following a week-long exposure to (a) LD cycles of 10:10h, 12:12h and 14:14h, or (b) LD12:12h with different light intensities (10, 100 and 1000lx), or (c) 12:12h warm/cold (WC) cycles of 25:18°C (WC1) and 29:25°C (WC2), or (d) WC1 or WC2, in-phase or out-of-phase with LD. The results revealed that both LD and WC altered the τ of FD and BD flies, and considerably reduced the selection-mediated difference between the two stocks. LD10:10 caused more severe after-effects on τ compared to LD12:12 and LD14:14. Among the WC cycles, WC1 which had a higher contrast caused period shortening. Irrespective of the phase relationship, imposition of LD cycles on WC cycles made no difference to the extent of after-effects; however, interestingly there was a reversal in the trend, in that, now WC2 with LD caused most drastic reduction in τ. These results suggest that cyclic environments modulate the circadian organization of Drosophila melanogaster altering the selection-mediated correlation between pre-adult development time and clock period. [Copyright &y& Elsevier]

Highlights: [•] Multi-crystalline silicon and amorphous-silicon power plants have been compared. [•] The performance ratio (PR) of the mc-Si power plant ranges from 57.1 to 93.14. [•] For a-Si power plant, PR ranges from 53.72 to 87.64. [•] The a-Si solar PV power plant has high capture losses as compared to the mc-Si. [ABSTRACT FROM AUTHOR]

Thiswork describes the use of direct current (DC) cyclic voltammetry(CV) and alternating current (AC) electrochemical impedance spectroscopy(EIS) as a means to monitor an electrochemical interface of differentmass flow direction induced polyaniline (PANI) film in IL (BmimPF6). Observed by SEM, vertical mass flow (VMF) and horizontalmass flow (HMF) induce porous nanorod and compact granular morphologyof PANI, respectively. The present work explores in detail analysisof double layer capacitance, polarization resistance, diffusion mechanism,as well as other electrochemical features associated with the PANI–ILinterface. A comparatively higher value of capacitance obtained forVMF PANI film from CV measurement confirms the higher electroactivityat the VMF electrode than the HMF film. Impedance spectroscopy, usinga small amplitude perturbation, confirms the CV result. Impedancemeasurement gives a value of capacitance larger than that from CVwhere the amplitude of the perturbation is much larger. The implicationsof these results for its potential application in energy storage devicesare discussed. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) films were deposited by electrochemical polymerization of aniline monomer on a fluorine-doped glass substrate at room temperature under different electric field directions. The as-synthesized PANI films obtained at different growth cycles were characterized by AC impedance spectroscopy and scanning electron microscopy (SEM). The results revealed that the film morphology, transport kinetics, and electrical properties are strongly dependent on the electric field direction and magnitude of the applied field during electropolymerization. The SEM morphology and AC impedance (modulus spectroscopy) indicate that a more homogeneous, high-porous, and conducting PANI film is induced by horizontal electric field direction (HEFD) electrodeposition, whereas the modulus spectroscopy of the PANI film deposited by vertical electric field direction (VEFD) reveals that VEFD deposition favours two-dimensional growth of PANI. The obtained polymer is more of dielectric in nature due to preferable dendritic growth which is supported by SEM analysis. [ABSTRACT FROM AUTHOR]

Insects including the fruit fly Drosophila melanogaster are under intense pressure to develop rapidly because they inhabit ephemeral habitats. We have previously shown that when selection for faster development was artificially imposed on D. melanogaster in the laboratory, reduction of pre-adult development time and shortening of the clock period occurs, suggesting a role for circadian clocks in the regulation of life history traits. Circadian clocks in D. melanogaster have also been implicated in the control of metabolic pathways, ageing processes, oxidative stress and defense responses to exogenous stressors. In order to rigorously examine correlations between pre-adult development time and other life history traits, we assayed pre-adult survivorship, starvation and desiccation resistance, body size and body weight, fecundity and adult lifespan in faster developing populations of D. melanogaster. The results revealed that selection for faster pre-adult development significantly reduced several adult fitness traits in the faster developing flies without affecting pre-adult survivorship. Although overall fecundity of faster developing flies was reduced, their egg output per unit body weight was significantly higher than that of controls, indicating that reduction in adult lifespan might be due to disproportionate investment in reproduction. Thus our results suggest that selection for faster preadult development in D. melanogaster yields flies with higher reproductive fitness. Because these flies also have shorter clock periods, our results can be taken to suggest that pre-adult development time and circadian clock period are correlated with various adult life history traits in D. melanogaster, implying that circadian clocks may have adaptive significance. [ABSTRACT FROM AUTHOR]

Abstract: This article explores the potential of 1kWP low-concentration photovoltaic (LCPV) system for commercial purposes. Real-time analysis of in-house developed LCPV system shows better performance than the flat panel PV systems. Under actual test conditions (ATC), the open-circuit voltage (V OC ) decreases with temperature coefficient of voltage ≈−0.061V/K. The dynamic resistance is found to have a positive coefficient of module temperature i.e., dr d /dT≈0.49Ω/K. The annual energy generation of 1kWP LCPV power plant is envisaged as 1747.2kWh/kWP while the annual average daily final yield, reference yield and array yield were 3.76, 5.09 and 4.29h/day, respectively. The annual average daily performance ratio and capacity factor are 72% and 14%, respectively. The annual average daily system losses and capture losses are 0.57 and 0.80h/day correspondingly. [Copyright &y& Elsevier]

Localized surface plasmon resonance incurred by silver nanoparticles is used to enhance the photoelectric conversion efficiency of a TiO nanorod-based dye-sensitized solar cell (DSSC). Improved light transmission is observed experimentally in silver nanoparticle-coated FTO glass. The transmission data are used to explore the effect on electrical parameters of DSSC using theoretical model. Current density increased from 11.7 to 12.34 mA/cm and open-circuit voltage increased from 704 to 709.5 mV. Overall efficiency enhancement of 6.67 % is observed in TiO nanorod-based DSSC due to plasmon-induced light trapping. [ABSTRACT FROM AUTHOR]

Abstract: The estimation of steady state and dynamic parameters is indispensable to extract maximum power from solar photovoltaic system. This article aims to extract steady state and dynamic parameters for a low-concentration photovoltaic system under actual test conditions. A theoretical model is reported to estimate dynamic resistance under varying concentration and temperature for low-concentration photovoltaic system. When the concentration ratio is changed from 1 sun to 5.17 suns the maximum power delivered by low-concentration photovoltaic system increased by threefold. The results show that the higher solar PV module temperature has negative impact on the open circuit voltage for a given concentration with negative temperature coefficient of ≈−0.021V/K. The observed dynamic resistance was in the range of 17.99 to 24.84Ω for the low-concentration photovoltaic system under actual test conditions. [Copyright &y& Elsevier]

Although, circadian clocks are believed to be involved in the regulation of life-history traits such as pre-adult development time and lifespan in fruit flies Drosophila melanogaster, there is very little unequivocal evidence either to support or refute this. Here we report the results of a long-term study aimed at examining the role of circadian clocks in the temporal regulation of pre-adult development in D. melanogaster. We employed laboratory selection protocol for faster pre-adult development on four large, outbred, random mating populations of Drosophila. We assayed pre-adult development time and circadian period of locomotor activity rhythm of these flies at regular intervals of 5-10 generations. After 50 generations of selection, the overall egg-to-adult duration in the selected stocks was reduced by ~29 h (~12.5 %) relative to controls, with the selected populations showing a concurrent reduction in time taken to hatching, pupation and wing pigmentation, by ~2, ~16, and ~25.2 h, respectively. Furthermore, selected populations showed a concomitant reduction in the circadian period of locomotor activity rhythm, implying that circadian clocks and development time are correlated. Thus, our study provides the first ever unequivocal evidence for the evolution of circadian clocks as a correlated response to selection for faster pre-adult development, suggesting that circadian clocks and development are linked in fruit flies D. melanogaster. [ABSTRACT FROM AUTHOR]

Piecewise linear parabolic trough collector (PLPTC) is designed and developed to concentrate solar radiation on monocrystalline silicon based photovoltaicmodule. Atheoreticalmodel is used to performelectrical energy and exergy analysis of low-concentration photovoltaic (LCPV) system working under actual test conditions (ATC).Theexergy efficiency of LCPV system is in the range from 5.1% to 4.82% with increasing rate of input exergy rate from 30.81W to 96.12W, when concentration ratio changes from 1.85 to 5.17 Sun. Short-circuit current shows increasing trend with increasing input exergy rate of 0.011 A/W. Power conversion efficiency decreases from 7.07 to 5.66%, and open-circuit voltage decreases from 9.86 to 8.24V with temperature coefficient of voltage 0.021 V/K under ATC. The results confirm that the commercially available silicon solar PV module performs satisfactorily under low concentration. [ABSTRACT FROM AUTHOR]

The steady-state current-voltage curve and dynamic response of a dye-sensitized solar cell (DSSC) is mathematically modeled based on electrical equivalent circuit. The effect of temperature and illumination on the steady-state and dynamic parameters of dye-sensitized solar cells is studied. It is found that the dynamic resistance of DSSC decreases from 619.21Ω to 90.34Ω with the increase in illumination level from 200W/m² to 800W/m². A positive temperature coefficient of dynamic resistance is observed. The interfacial charge transfer and recombination losses at the oxide/dye/electrolyte interface are found to be the most influential factor on the overall conversion efficiency and included in the mathematical model. The saturation current of rectifying diode and saturation current of recombination diode are responsible for the transfer recombination losses and have major influence on the overall conversion efficiency. [ABSTRACT FROM AUTHOR]