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This paper studies the chromatic polynomial of some special graphs like path graph, ladder graph and grid graph using the concept of digonalization of transfer matrix to solve simultaneous recurrence relation. The aim of this paper is to solve an open problem on the chromatic polynomial of grid graph (Problem 8.1 of Selected Topics in Graph Theory, Volume 3 which is edited by Lowell W. Beineke and Robin J. Wilson) and give general formula of the chromatic polynomial in λ of grid graph P 3 □ P n , where n ∈ N without any condition on n where λ denotes number of available colors. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is an immune mediated chronic inflammatory disorder of gastrointestinal tract, which has underlying multifactorial pathogenic determinants such as environmental factors, susceptibility genes, gut microbial dysbiosis and a dysregulated immune response. Human gut is a frequent inhabitant of complex microbial ecosystem encompassing bacteria, viruses, parasites, fungi and other microorganisms that have an undisputable role in maintaining balanced homeostasis. All of these microbes interact with immune system and affect human gut physiology either directly or indirectly with interaction of each other. Intestinal fungi represent a smaller but crucial component of the human gut microbiome. Besides interaction with bacteriome and virome, it helps in balancing homoeostasis between pathophysiological and physiological processes, which is often dysregulated in patients with IBD. Understanding of gut mycobiome and its clinical implications are still in in its infancy as opposed to bacterial component of gut microbiome, which is more often focused. Modulation of gut mycobiome represents a novel and promising strategy in the management of patients with IBD. Emerging mycobiome-based therapies such as diet interventions, fecal microbiota transplantation (FMT), probiotics (both fungal and bacterial strains) and antifungals exhibit substantial effects in calibrating the gut mycobiome and restoring dysbalanced immune homeostasis by restoring the core gut mycobiome. In this review, we summarized compositional and functional diversity of the gut mycobiome in healthy individuals and patients with IBD, gut mycobiome dysbiosis in patients with IBD, host immune-fungal interactions and therapeutic role of modulation of intestinal fungi in patients with IBD. [ABSTRACT FROM AUTHOR]

Background: Anophthalmos/microphthalmos spectrum is a rare congenital eye disorder and concurrence of a cystic intraorbital lesion is even rarer. Every so often it presents as a diagnostic enigma for the clinician as well as radiologist. The occurrence of anomaly is linked with early intraembryonic insult and is closely linked with neuroectodermal development of the eyeball. There is a wide range of differential diagnoses for the intraaorbital cysts associated with microphthalmos cases ranging from colobomas to teratomas. The radiological findings in the coloboma gamut are poorly understood with a paucity of the literature regarding the same. Early and correct diagnosis is imperative for the proper management of the patient. Case presentation: We present the radiological findings in three patients presenting at different ages with a basic approach pattern. Conclusions: Knowledge of the radiological findings in cases of intraorbital colobomatous cysts and associations along with their embryological basis would help in making the correct diagnosis ensuing timely and accurate patient management. [ABSTRACT FROM AUTHOR]

For a finite group G, the power graph of G, denoted by P(G), is a special type undirected graph which has the group elements as its vertex set and two distinct vertices are adjacent if one is non-negative power of other. In this paper, we are interested in the extreme vertices of the power graph P(G) of a finite group G. We determine whether a vertex of P(G) is extreme vertex or not if G is permutation group on n symbols using the concept of disjoint cyclic decomposition of vertex as element of permutation group on n symbols. [ABSTRACT FROM AUTHOR]

The present investigation was conducted to assess the nutritional diverseness and identify novel genetic resources to be utilized in chickpea breeding for macro and micro nutrients. The plants were grown in randomized block design. Nutritional and phytochemical properties of nine chickpea genotypes were estimated. The EST sequences from NCBI database were downloaded in FASTA format, clustered into contigs using CAP3, mined for novel SSRs using TROLL analysis and primer pairs were designed using Primer 3 software. Jaccard's similarity coefficients were used to compare the nutritional and molecular indexes followed by dendrograms construction employing UPGMA approach. The genotypes PUSA-1103, K-850, PUSA-1108, PUSA-1053 and the EST-SSR markers including the 5 newly designed namely ICCeM0012, ICCeM0049, ICCeM0067, ICCeM0070, ICCeM0078, SVP55, SVP95, SVP96, SVP146, and SVP217 were found as potential donor/marker resources for the macro–micro nutrients. The genotypes differed (p < 0.05) for nutritional properties. Amongst newly designed primers, 6 were found polymorphic with median PIC (0.46). The alleles per primer ranged 1 to 8. Cluster analysis based on nutritional and molecular diversities partially matched to each other in principle. The identified novel genetic resources may be used to widen the germplasm base, prepare maintainable catalogue and identify systematic blueprints for future chickpea breeding strategies targeting macro–micro nutrients. [ABSTRACT FROM AUTHOR]

The strong ground motions at a particular site played an important part from the point of view of seismic hazard estimation. For this purpose, various methods/techniques are present in the seismological literature. A hybrid technique, based on the composite source model and envelope technique has been modified in the present research to simulate the ground motions for an earthquake at the surface level. For modifying the technique, the effects of high-frequency parameter kappa (κ) and empirical transfer functions have been included in the hybrid method. The reliability of the modified hybrid technique has been confirmed by modelling the empirical accelerograms of the 2011 Sikkim earthquake (M 6.9). The empirical transfer functions have been computed by the use of observed data of the earthquake. The causative fault of the earthquake has been identified by simulating the accelerograms considering both the nodal planes separately. The essential parameters of the strong ground motions are peak ground acceleration (PGA), duration of the accelerograms, response and Fourier spectrum of simulated accelerograms have been found consistent with recorded ones. Based on the comparison between simulated and observed accelerograms, the regression relation for attenuation of PGA and quality factor (Q) for the region have been identified. The hybrid technique modified here is capable of generating realistic simulated accelerograms for future similar earthquakes in the region. These findings might be obliging in preparing seismic-scenario hazard maps of the region required in the mitigation plans. Article Highlights: Hybrid Technique is modified by introducing the high-frequency parameter (kappa) and empirical transfer function. Modified Hybrid technique is used to model the empirical accelerograms for 2011, Sikkim Earthquake (Mw 6.9). Constrained the attenuation relation of PGA and frequency-dependent Q-relation for the Sikkim Himalaya region. [ABSTRACT FROM AUTHOR]

Optimum quantity of nitrogen fertilizer to maximize the production and minimize the cost of cultivation is need of the day. Therefore, it is obligatory to know the nitrogen demand of potato crop for economical production and minimizing the negative effect on environment. Consequently, an experiment was conducted at CCS Haryana Agricultural University, Hisar, for 2 years to investigate the effect of nitrogen levels on newly developed potato varieties Kufri Surya and Kufri Sadabahar. Nitrogen dose of 300 kg/ha gave the highest values for growth parameters which were at par with 225 kg/ha nitrogen, whereas the maximum values for yield parameters as well as dry matter content (tubers + haulms) were recorded with nitrogen dose of 225 kg/ha. It means nitrogen above 225 kg/ha has no significant effect on crop yield parameters. The variety Kufri Sadabahar gave significantly higher values for all the growth and yield parameters than Kufri Surya. It was concluded that the variety Kufri Sadabahar supplied with nitrogen 225 kg/ha gave the maximum productivity (388.7 q/ha), net income (Rs. 2,08,576/ha) and benefit to cost ratio (2.31). [ABSTRACT FROM AUTHOR]

In northern India, chickpea experiences abrupt heat and drought stress during the late developmental stage and entails significant production loss. In the present study, the effect of heat stress and combined stress (heat and drought) was assessed in five varieties of chickpea along with the underlying mechanism of cross-tolerance by priming. Healthy seedlings (24 days old) were primed with mild drought stress and exposed to three different temperatures, i.e., 38 °C, 35 °C, and 32 °C for 12, 24, and 36 h respectively, and also in combination with drought. The damage and tolerance were evaluated based on biochemical and physiological indicators. Results indicate that significant response was observed at 35 °C as compared to 32 and 38 °C in terms of decrease in leaf water content, increased electrolyte leakage and lipid peroxidation, decreased chlorophyll content, increased accumulation of proline and total sugars, and increased antioxidative activity of superoxide dismutase, catalase, guaiacol peroxidase, ascorbate peroxidase, and glutathione reductase. The consequence of combined stress was more distinct than the individual heat stress and cannot be extrapolated from the synergistic effect of the two stresses. In addition, priming induced cross-tolerance at 35 °C by improving the membrane damage, photorespiration, photosynthetic pigment, osmolyte accumulation, and some antioxidative enzymes. On the basis of all the above parameters, PDG4 was identified as the best performing variety and tolerant to heat stress while GPF2 was the worst performing and sensitive to heat stress. It can be inferred that both severity and duration of stress are important and priming can be considered as an important tool to induce cross-tolerance in crop plants. [ABSTRACT FROM AUTHOR]

The 2011 Sikkim earthquake (M 6.9) of the Himalaya has shown that a moderate size earthquake may also cause severe damage to the region. Simulated accelerograms using a modified hybrid technique have been generated at spatially distributed 702 points for a moderate size (M 6.9) earthquake in the Sikkim region of Himalaya to evaluate the seismic hazard in the region. The peak ground acceleration (PGA) values and response spectra have been derived from the simulated accelerograms. The synthetic PGA values, corresponding modified mercalli (MM) intensity values and response spectral acceleration values have been contoured to present the scenario hazard maps of the region. A PGA value of 400 cm/s2 has been estimated in the region near the epicentre of the earthquake. The response spectral acceleration values for five periods corresponding to the natural period (T) of single-storey buildings, double-storey buildings, 3–4 storey buildings, tall buildings and high-rise buildings have been obtained. The maximum values of response spectral accelerations estimated in the centre of meizoseismal zone are 1200 cm/s2 (T = 0.1 s), 1800 cm/s2 (T = 0.2 s), 900 cm/s2 (T = 0.5 s), 800 cm/s2 (T = 1.0 s) and 80 cm/s2 (T = 6 s). The decay curves show that PGA values in the west direction are lower as compared to the values in other directions at similar distances. Also, it has been observed that the PGA and spectral acceleration values decay slowly in the west direction compared to other directions. The scenario hazard maps present here are expected to be useful for mitigating seismic hazards from the region as these maps indicate the damage potential due to future moderate size earthquakes in the region. Article Highlights: The application of a modified hybrid technique has been presented to evaluate the seismic hazard based on simulating accelerograms for a moderate size earthquake in the Sikkim region of Himalaya. The synthetic accelerograms have been generated at 702 points distributed spatially on a grid. The scenario hazard maps showing the spatial distribution of PGA values, MM intensity values and response spectral acceleration values at different periods. [ABSTRACT FROM AUTHOR]

One of the major challenges for potato producers is to maximize its yield and quality by properly managing the nitrogen fertilization. An experiment was conducted under North-Western Indian conditions during two consecutive years with two potato varieties, i.e. Kufri Surya and Kufri Sadabahar under five nitrogen levels (0, 75, 150, 225, and 300 kg/ha) in a randomized block design (factorial) with three replications. The results revealed that most of the growth parameters and NPK uptake by haulms were maximum at 300 kg/ha nitrogen level that was statistically at par with nitrogen level 225 kg/ha, while for yield parameters and NPK uptake by tubers, nitrogen level 225 kg/ha was the best with the highest value. It depicts that crop yield parameters are negatively affected by the nitrogen dose of above 225 kg/ha. So far the variety is concerned, Kufri Sadabahar was significantly better for all the noted growth and yield parameters as well as NPK uptake by tubers and haulms than the variety Kufri Surya. Regarding the soil fertility behaviour after harvest of the crop, higher left over nitrogen in soil was recorded for the highest applied nitrogen dose, whereas phosphorus and potassium left over in soil was recorded more where no nitrogen was applied (control plot), which was closely followed by 75 kg/ha nitrogen level. The results provide useful recommendations for the improvement of nitrogen fertilization rate for these two varieties in sub-tropical region of north western India in Haryana state. [ABSTRACT FROM AUTHOR]

Water, the primary source of life, is contaminated with various organic/inorganic impurities in the course of development. Organic dyes, a waste product from dying industries, have evolved as one of the major contributor to water pollution. The present work involves the photocatalytic degradation of malachite green dye as a model substrate using zinc oxide nanoparticles (ZnO NPs) and its composite with β-cyclodextrin (β-CD). ZnO NPs are found to be a worthy catalyst due to their bandgap and easy availability. The role of β-CD in ZnO photocatalyst is explored. With ZnO NPs, electron–hole recombination takes place very easily; hence, to restrict this recombination β-CD has been used. We have characterized the synthesized nanomaterials by using powder X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, diffuse reflectance spectroscopy (DSR), scanning electron microscopy and transmission electron microscopy (TEM). Various parameters, such as the concentration of dye, pH and amount of catalyst have optimized for the photocatalysis process. More basic medium adsorption is more favourable than degradation, which decreases the reusability of the catalyst. Based on the photodegradation efficiency and rate constant (k), we observed that ZnO–β-CD showed better photocatalytic activity than ZnO NPs. The plausible mechanism for photocatalytic degradation has also been reported with the help of photoluminescence spectra and scavenger activity. [ABSTRACT FROM AUTHOR]

In the analysis of seismic hazards of a particular region, the site response functions play a significant role. Site response functions for the central seismic gap become more important as the estimated possibility of manifestation of the earthquake (M ≥ 8) is 31% in a time window of fifty years (Khattri in Proc Indian Academy Sci Earth Planetary Sci 108(2): 87–92). This emphasizes the importance of analysis of seismic hazards in this region. The site effect or response functions have been assessed for the central seismic gap region in the present study using 87 recorded local events recorded at 50 sites located in the central seismic gap region of Himalaya. Among 50 stations, 9 stations are located in Higher Himalaya, 30 stations are situated in Lesser Himalaya, 06 stations are present in Sub-Himalaya, and the remaining 05 stations are situated in Indo-Gangetic plain. Here, the horizontal-to-vertical spectral ratio method has been used for evaluating the site response functions. The site response functions have been evaluated at different frequencies related to various types of structures. The estimated mean site response function value at the principal frequency (predominant) is found to be 6.2 for Higher Himalaya, 6.5 for Lesser Himalaya, 7.03 for Sub-Himalaya, and 9.6 for the stations located in the Indo-Gangetic plain. Further, the estimated site response functions and the station's broad geology have been correlated with each other. With the help of estimated site response functions at various frequencies corresponding to various storey structures, the seismic hazard in the central seismic gap area has been discussed. The calculated site response functions are further useful for different studies like for simulation in strong ground motions and evaluating the earthquake source parameters. [ABSTRACT FROM AUTHOR]

Corporate social responsibility (CSR) is a strategic tool that empowers competitive differentiation through coagulation of societal and business objectives. Against this context, it has been proposed that rational and emotional factors can develop a mechanism that can elucidate consumers' reaction towards CSR. To date, literature that evaluates the role of rational and emotional variables in this realm is practically nonexistent. The objective of the current study is to develop a parsimonious model to analyze the inter-relationship of CSR and loyalty by incorporating mediators, rational (customer satisfaction) and emotional (brand affect), in the low-involvement product category. The information provided by 294 valid responses was analyzed using structural equation modelling and the PROCESS method. The finding supported the hierarchical chain of effects of CSR practices influencing customer satisfaction (rational variable), which further impacts brand trust and brand affect (emotional variable) and finally paves its way for brand loyalty in the low-involvement product category. [ABSTRACT FROM AUTHOR]

Ophiocordyceps sinensis (Berk.) is a fungus closely related to medicinal mushroom, which belongs to the family Ophiocordycipitaceae. It is a well-known and rich herbal source of bioactive active constituents. The medicinal mushroom has garnered worldwide attention owing to its multifarious bioactivities. This mushroom grows on the larva of ghost moths (Hepialidae) and produces fruiting bodies, which serve as a vital natural source of medicine and supplementary diets. On account of the diverse pharmacological and bioactive constituents present in O. sinensis, it has been established as a potential antioxidant, anticancer, antibacterial, anti-proliferative, anti-inflammatory agent that has been successfully used for treating several health issues, including hypoxia-related problems encountered by mountaineers, pilgrims, tourists and soldiers occurring at high-altitude regions such as acute mountain sickness (AMS), high-altitude pulmonary edema (HAPE), high-altitude cerebral edema (HACE), frostbite, chilblains, hypothermia, etc. The most important pharmacologically active compounds present in the O. sinensis include nucleobases and its derivatives (adenosine, cordycepin, 3-deoxyadenosine, AMP, GMP, UMP, guanosine, uridine), polysaccharides (mannose, glucose, galactose, rhamnose, arabinose, xylose, galactose), proteins, peptides and steroids. This article focuses on the various research endeavors undertaken to scientifically establish the medicinal properties of O. sinensis, highlighting the various principally active compounds, their pharmacological action, drug designing and development and future perspective for various health benefits. [ABSTRACT FROM AUTHOR]

Today, environment pollution control is a matter of concern, everybody is willing to make a product that should be ecofriendly. Nowadays, water resources are full of untreated waste materials, discharge of hazardous and toxic dyes coming from textile and other chemical industries. These environmental hazards are difficult to remove by commercial water treatment plans, thus we need something that would present an efficient means for removal of these hazards. In this research paper, we have synthesize silver nanoparticle in a green way by using aqueous extract of Allium cepa (onion), and further these silver nanoparticle were tested for the catalytic degradation of various dyes by UV/Visible spectroscopy and silver nanoparticle showed reduction in dyes intensity after a particular period of incubation time. SEM and TEM, Particle size and Zeta potential analysis was done to analyze the surface morphology, particle size range and stability of the silver nanoparticle. Greenly synthesized silver nanoparticle was found to be spherical in shape, having particle size value ranged from 50 to 100 nm with a zeta potential value of −29 mV. An EDX spectroscopy method was used to confirm the presence of silver nanoparticle in the synthesized material. An X-ray crystallography was done to ensure the crystallinity of the silver nanoparticle. Further an ATR-FTIR was performed to confirm the capping of the silver nanoparticle with the phenolic group of the onion. All these study emphasized that silver nanoparticle capped with onion (AgNPs@Ac) is the excellent catalyst for the reduction of hazardous and toxic dyes as well as they serve best purpose of the eco-friendly approach. [ABSTRACT FROM AUTHOR]

The aim of the present study was to develop liposomal gel containing ketoconazole and neem extract for the treatment of seborrheic dermatitis in an effectual means. Azoles derivatives that are commonly used to prevent superficial fungal infections include triazole category like itraconazole. These drugs are available in the form of oral dosage that required a long period of time for treatment. Ketoconazole is available in the form of gel but is not used with any herbal extract. Neem ( Azadirachta indica) leaves show a good anti-bacterial and anti-fungal activity and have great potential as a bioactive compound. The thin film hydration method was used to design an herbal liposomal preparation. The formulation was further subjected to their characterization as particle size, zeta potential, entrapment efficiency, % cumulative drug release, and anti-fungal activity and it was also characterized by the mean of their physicochemical properties such as FTIR, SEM, DSC, TGA, and AFM. The results show that the formulation of liposomes with neem extract F12 were found to be optimum on the basis of entrapment efficiency in the range 88.9 ± 0.7%, with a desired mean particle size distribution of 141.6 nm and zeta potential − 45 mV. The anti-fungal activity of liposomal formulation F12 was carried out against Aspergillus niger and Candida tropicalis by measuring the inhibition zone 8.9 and 10.2 mm, respectively. Stability of optimized formulation was best seen at refrigerated condition. Overall, these results indicated that developed liposomal gel of ketoconazole with neem extract could have great potential for seborrheic dermatitis and showed synergetic effect for the treatment. [ABSTRACT FROM AUTHOR]

The present study is attempted to analyze the thermoelastic interactions in a homogeneous isotropic electro-microstretch semi-space caused by mechanical source acting on the initially stressed surface. The problem is treated on the basis of two-temperature thermoelasticity without energy dissipation proposed by Youssef. Normal mode analysis is applied to derive the exact expressions for displacement components, force stresses, couple stress, microstress, conductive temperature, thermodynamic temperature and electric field. Numerical computations have been performed for magnesium crystal material to depict the response of mechanical source in the medium for thermally insulated boundary. Some comparisons have been made in figures to estimate the effects of two-temperature parameter and initial stress. [ABSTRACT FROM AUTHOR]

The present paper is aimed to model and study the characteristics of various reflected waves in a homogeneous isotropic piezoelectric thermo-microstretch viscoelastic solid within the context of theory of thermoelasticity without energy dissipation. It is shown that there exists three sets of coupled longitudinal and two sets of coupled transverse waves with different speeds in a two-dimensional model of the solid. The speeds of all the existing waves are found to be complex valued and frequency dependent. The speeds of coupled longitudinal waves are found to be influenced by the electric effect, while the speeds of transverse waves remain unaffected to the electric effects. Reflection coefficients and energy ratios of various reflected waves are presented when (1) a set of coupled longitudinal waves is made incident and (2) a set of coupled transverse waves is made incident. The numerical computations have been carried out to calculate the phase speeds, reflection coefficients and energy ratios with the help of Matlab programming for aluminum-epoxy like material. The numerical values of the modulus of reflection coefficients and phase speeds are presented graphically to exhibit the viscous effects. The energy ratios as functions of angle of incidence are also shown graphically. Some particular cases of interest have been inferred from the present study. [ABSTRACT FROM AUTHOR]

Curcumin is a major bioactive compound of turmeric that exerts its anti-inflammatory effects by suppressing the many pro-inflammatory cytokines and chemokines in a number of cell types and pathologic conditions. Interleukin-18 (IL-18) is a novel pro-inflammatory cytokine which plays an important role not only in generating Th1 responses but also in inducing severe inflammatory reactions. As curcumin induced inhibition of IL-18 production in keratinocytes and mice is well known, effect of curcumin on IL-18 release in macrophages remains unknown. Hence, this present study has been designed to evaluate the effect of curcumin on IL-18 production and necrotic cell death in murine macrophages-like cells treated with or without lipopolysaccharide (LPS). The IL-18 secretion in cell culture supernatants was assayed by enzyme-linked immunosorbent assay and cytotoxicity was determined by lactate dehydrogenase release assay. Our results demonstrate that curcumin significantly inhibited the production of pro-inflammatory cytokine IL-18 in E.coli LPS stimulated murine macrophage-like cells RAW264.7 in a concentration-dependent manner. Interestingly, curcumin had no cytotoxic effect on murine macrophage-like cells. Our findings suggest that curcumin may be used as a potential therapeutic agent for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Extensive efforts are being made to use biocatalysts for addressing an important millennium development goal i.e. global warming/climate change with recourse to CO capture valorisation and storage (CCVS). New advanced enzyme-based catalysts with significantly improved catalytic properties and stability have been discussed in detail with specific reference to carbonic anhydrase for biomimetic CO sequestration. [ABSTRACT FROM AUTHOR]

Carbonic anhydrase (CA) has been immobilized on chitosan stabilized iron nanoparticles (CSIN) for the biomimetic carbonation reaction. CSIN was characterized using scanning electron microscope, energy dispersive X-ray, X-ray diffraction spectroscopy, and Fourier transform infrared analysis. The effect of various parameters such as pH, temperature and storage stability, on immobilized CA was investigated using a p-NPA assay. Kinetic parameters of immobilized and free CA ( K and V values) were also evaluated. The K and V for immobilized CA was 1.727 mM and 1.189 μmol min ml, respectively, whereas for free enzyme the K and V was 1.594 mM and 1.307 μmol min ml, respectively. It was observed that the immobilized enzyme had longer storage stability and retained 50 % of its initial activity upto 30 days at room temperature. CA immobilized on CSIN has been used for hydration of CO, and the results were validated by using a gas chromatographic method. Proof of concept has been established for the biomimetic carbonation reaction. Immobilized CA show reasonably good CO sequestration capacity of 21.55 mg of CaCO/mg of CA as compared to CO sequestration capacity of 34.92 mg of CaCO/mg of CA for free CA respectively, under a limiting concentration of CO (14.5 mg of CO/10 ml). [ABSTRACT FROM AUTHOR]

In the present investigation, we report the immobilization of the enzyme tyrosinase on mesoporous silica material, i.e. MCM-41 to serve as a tool for the detection of phenol. The enzyme immobilized onto the MCM-41 matrix has shown to retain its activity and is quite stable. The immobilization of enzyme has been discussed, and the various factors that affect the loading of enzyme onto MCM-41 were studied and optimized. The applicability of tyrosinase-immobilized MCM-41 was then demonstrated for the detection of phenol. The lowest detectable concentration of phenol by tyrosinase-immobilized MCM-41 was observed to be 1 mg l. The factors influencing the detection of phenol were then studied in detail. [ABSTRACT FROM AUTHOR]

Heat shock proteins (Hsps) or molecular chaperones, are highly conserved protein families present in all studied organisms. Following cellular stress, the intracellular concentration of Hsps generally increases several folds. Hsps undergo ATP-driven conformational changes to stabilize unfolded proteins or unfold them for translocation across membranes or mark them for degradation. They are broadly classified in several families according to their molecular weights and functional properties. Extensive studies during the past few decades suggest that Hsps play a vital role in both normal cellular homeostasis and stress response. Hsps have been reported to interact with numerous substrates and are involved in many biological functions such as cellular communication, immune response, protein transport, apoptosis, cell cycle regulation, gametogenesis and aging. The present review attempts to provide a brief overview of various Hsps and summarizes their involvement in diverse biological activities. [ABSTRACT FROM AUTHOR]

Nanoparticle technology is being increasingly used in environmental sciences. We prepared single enzyme nanoparticle (SEN) by modifying the surface of carbonic anhydrase (CA) with a thin layer of organic/inorganic hybrid polymer. SEN-CA appears to be improving the stability of free enzyme. CA, as ubiquitously found enzyme, is involved in gaseous CO sequestration and is being looked as a promising candidate for combating global warming. We report here physical characterization of SEN-CA using transmission electron microscope (TEM), Fourier-transform infrared analysis (FTIR), X-ray diffraction analysis (XRD), and energy dispersive X-ray (EDX). Average size of SEN-CA particles appears to be in the range of 70-80 nm. We also report the effect of SEN formation on the kinetic parameters of free CA such as Michaelis-Menten constant ( K), maximum reaction velocity ( V), and storage stability of free CA and SEN-CA. The V of SEN-CA (0.02857 mmol/min/mg) and free enzyme (0.02029 mmol/min/mg) is almost similar. K has decreased from 6.143 mM for SEN-CA to 1.252 mM for free CA. The stabilization of CA by SEN formation results in improved the half-life period (up to 100 days). The formation of carbonate was substantiated by using gas chromatography (GC). The conversion of CO to carbonate was 61 mg of CaCO/mg of CA and 20.8 mg of CaCO/mg of CA using SEN-CA and free CA, respectively. [ABSTRACT FROM AUTHOR]