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Background: Bacterial vaginosis (BV) is a common clinical manifestation of a perturbed vaginal ecology associated with adverse sexual and reproductive health outcomes if left untreated. The existing diagnostic modalities are either cumbersome or require skilled expertise, warranting alternate tests. Application of machine‐learning tools to heterogeneous and high‐dimensional multi‐omics datasets finds promising potential in data integration and may aid biomarker discovery. Objectives: The present study aimed to evaluate the potential of the microbiome and metabolome‐derived biomarkers in BV diagnosis. Interpretable machine‐learning algorithms were used to evaluate the utility of an integrated‐omics‐derived classification model. Methods: Vaginal samples obtained from reproductive‐age group women with (n = 40) and without BV (n = 40) were subjected to 16S rRNA amplicon sequencing and LC–MS‐based metabolomics. The vaginal microbiome and metabolome were characterized, and machine‐learning analysis was performed to build a classification model using biomarkers with the highest diagnostic accuracy. Results: Microbiome‐based diagnostic model exhibited a ROC‐AUC (10‐fold CV) of 0.84 ± 0.21 and accuracy of 0.79 ± 0.18, and important features were Aerococcus spp., Mycoplasma hominis, Sneathia spp., Lactobacillus spp., Prevotella spp., Gardnerella spp. and Fannyhessea vaginae. The metabolome‐derived model displayed superior performance with a ROC‐AUC of 0.97 ± 0.07 and an accuracy of 0.92 ± 0.08. Beta‐leucine, methylimidazole acetaldehyde, dimethylethanolamine, L‐arginine and beta cortol were among key predictive metabolites for BV. A predictive model combining both microbial and metabolite features exhibited a high ROC‐AUC of 0.97 ± 0.07 and accuracy of 0.94 ± 0.08 with diagnostic performance only slightly superior to the metabolite‐based model. Conclusion: Application of machine‐learning tools to multi‐omics datasets aid biomarker discovery with high predictive performance. Metabolome‐derived classification models were observed to have superior diagnostic performance in predicting BV than microbiome‐based biomarkers. [ABSTRACT FROM AUTHOR]

Carbon fibers passing current are subject to resistive heating. When failure occurs, this is related to their local temperature. The failure temperature and its location are estimated. The temperature variation is calculated using analytical models for electrical and thermal conductivities based on the temperature dependent electron–phonon relaxation time. In the absence of radiative heat loss, an analytic expression of temperature along the fiber is given from which a maximum possible emission current is derived and is governed by a single introduced parameter ω o. A method of treating the radiative heat loss is developed and is governed by a second parameter γ , which allows a rapid numerical means to calculate the correction to the analytic form. Heat variation along a thick carbon fiber is contrasted to that along a multi-walled carbon nanotube (MWNT): it is shown that the relative magnitude of ω o compared to γ determines that the analytical formula is a good approximation for MWNTs but requires numerical correction for fibers. Furthermore, it is shown that the analytical form of ω o specified a maximum current beyond which the carbon emitter fails due to thermal runaway. The theoretical models are used to interpret observed behavior of field emission from carbon fibers and the resulting damage they endure when the extracted field-emission current is high. Results from implementing the developed temperature variation model into the MICHELLE beam optics simulation code are presented, with an example application predicting the conditions for stable equilibrium operation as well as for the onset of fiber failure. [ABSTRACT FROM AUTHOR]

Plot of the spatial dependence of the temperature along a 3 m CNT for a value of the external electric field of E e x t =464.658 V/cm and for three different values of the CNT diameter, d =2, 2.1, and 2.2 nm. Plot of the temperature profile along a 2.1 nm diameter and a 3 m long CNT for an external electric field of E e x t =465.956 V/cm assuming that the temperature dependence of the electrical resistivity (T) is given by Eq. (32) where 0 is selected to be either 0(1)=3.26×10-5 m, 0(2)=2 0(1), or 0(3)=3 0(1). 2 for different values of the applied external electric field E e x t. From bottom to top, E e x t is equal to 440, 450, 455, 460, 463, and 464.658 V/cm, the latter being 0.001 kV/cm less than the value of the critical electric field E c at which thermal runaway occurs. [Extracted from the article]

An efficient algorithm is described to calculate the spatial dependence of the temperature distribution along a carbon nanotube (CNT) during field emission (FE). The algorithm considers the effects of Joule heating in the CNT and radiative losses from the CNT sidewall and tip. The CNT emission current density and the rate of heat exchange per unit area at the CNT tip due to either Henderson-cooling or Nottingham-heating effects are calculated using recent analytical expressions derived by Jensen [J. Appl. Phys. 126, 065302 (2019)]. The latter are valid in the thermionic and field emission regimes and in the transition region between these two extremes. The temperature dependence of the electrical resistivity ρ (T) and the thermal conductivity κ (T) of the CNT is also included in the model. It is shown that replacing ρ (T) and κ (T) by their spatial averages over the length of the CNT can lead to an overestimate of the value of the external electric field threshold at which thermal runaway of the CNT occurs. These results should be considered when calculating the field emission characteristics of CNT arrays such as from a carbon nanotube fiber whose FE properties are primarily determined by the FE properties of the array of CNTs at the tip of the fiber. Using the new algorithm, the simulation times to calculate the CNT FE characteristics and the spatial temperature distribution are found to be nearly two orders of magnitude faster compared to those required when both the current and energy exchange at the CNT tip are calculated numerically. [ABSTRACT FROM AUTHOR]

The selenocyanate dimer radical anion (SeCN)2•−, prepared by electron pulse irradiation of selenocyanate anion (SeCN)− in water, has been examined by transient absorption, time-resolved Raman spectra, and range-separated hybrid density functional (ωB97x and LC-ωPBE) theory. The Raman spectrum, excited in resonance with the 450 nm (λmax) absorption of the radical, is dominated by a very strong band at 140.5 cm−1, associated with the Se–Se stretching vibration, its overtones and combinations. A striking feature of the (SeCN)2•− Raman spectrum is the relative sharpness of the 140.5 cm−1 band compared to the S–S band at 220 cm−1 in thiocyanate radical anion (SCN)2•−, the difference of which is explained in terms of a time-averaged site effect. Calculations, which reproduce experimental frequencies fairly well, predict a molecular geometry with the SeSe bond length of 2.917 (±0.04) Å, the SeC bond length of 1.819 (±0.004) Å, and the CN bond length of 1.155 (±0.002) Å. An anharmonicity of 0.44 cm−1 has been determined for the 140.5 cm−1 Se–Se vibration which led to a dissociation energy of ∼1.4 eV for the SeSe bond, using the Morse potential in a diatomic approximation. This value, estimated for the radical confined in a solvent cage, compares well with the calculated gas-phase energy, 1.32 ± 0.04 eV, required for the radical to dissociate into (SeCN)• and (SeCN)− fragments. The enthalpy of dissociation in water has been measured (0.36 eV) and compared with the value estimated by accounting for the solvent dielectric effects in structural calculations. [ABSTRACT FROM AUTHOR]

Reproductive strategy of earthworm Polypheretima elongata was studied in different wastes under laboratory conditions with temperature 25±3°C and humidity 65-85% for span of 91 days (February to May) to understand their growth, reproductive potential and life cycle. Experimental set up was designed within the four different composite waste beddings and one control. Maximum rate of cocoon production and hatchling was recorded in kitchen waste with cow manure bedding (2.82±0.08 no. of cocoon/worm/week, 4.69±0.10 no .of hatchling/cocoon), while minimum score reported in domestic animal mixture manure bedding (1.26±0.06 no. of cocoon/worm/week, 2.85±0.05 no. of hatchling/cocoon). Consequently, lowest (25.12±0.18, 33.00±1.15 day) incubation and maturation period was recorded in kitchen waste with cow manure bedding, while highest (34.72±0.12, 53.67±2.60 day) was observed in bedding containing mixture of domestic animal manure. On the other hand, maize straw with cow manure and wheat straw with cow manure beddings exhibited moderate values. Maximum wet biomass achieved per earthworm (1.07±0.08 g/worms) in composites of kitchen waste with cow manure. These value were significantly (P<0.05) changed in different bedding materials. Therefore, this investigational result showed that bedding containing kitchen waste merged with cow manure is most ideal for its growth and development. [ABSTRACT FROM AUTHOR]

Microbial community profile associated with acidic pond sediments (APS) (pH = 3·0–4·5) of freshwater finfish aquaculture ponds (n = 8) was investigated. Sediment DNA extracted from the eight APS were subjected to high‐throughput sequencing of V3 and V4 regions which yielded 7236 operational taxonomic units (OTUs) at a similarity of 97%. Overall results showed higher proportion of bacterial OTUs than archaeal OTUs in all the APS. Euryarchaeota (23%), Proteobacteria (19%), Chloroflexi (17%), Crenarchaeota (5·3%), Bacteroidetes (4·8%), Nitrospirae (3·2%), Nanoarchaeaeota (3%) which together constituted 75% of the microbial diversity. At the genus level, there was high preponderance of methanogens namely Methanolinea (5·4%), Methanosaeta (4·5%) and methanotrops, Bathyarchaeota (5%) in APS. Moreover, the abundant phyla in the APS were not drastically affected by the administration of chicken slaughter waste (R‐group ponds) and commercial fish feed (C‐group ponds), since 67% of the OTUs generated remained common in the APS of both the groups of ponds. There was a minimal difference of 24–26% of OTUs between C‐group and R‐group ponds, suggesting the existence of a core microbial community in these ponds driven by acidic pH over the years. This study concludes that microbial diversity in pond sediment was influenced to a lesser extent by the addition of chicken slaughter waste but was majorly driven by acidic nature of the pond. [ABSTRACT FROM AUTHOR]

Soil pollution is a major problem in the presnt scenario of environmental degradation. Industrial effluents are directly or indirectly disposed to soil system and gradually hamper chemical and biological health of soil. They contain many inorganic chemicals including heavy metals like cadmium, chromium, copper, calcium, iron, lead, magnesium, manganese, mercury, nickel, potassium and zinc. Besides these chlorides, cyanides, sulphates, sulphides and phenolic compounds, synthetic dye, petrochemicals and nanoparticles are also generated from industries which cause soil pollution. It has been observed that effluent disposal makes soil brittle, infertile, barren and fluffy and produces bad smell and causes adverse impacts on faunal communities. Effluents cause detrimental effects on soil system and fauna inhabiting there in. Many arthropods and annelids are affected with hazardous industrial effluents in polluted sites as compared to the non-polluted one. Soil fauna were more affected near to the disposal sites as compared to the distant places. Virtually industrial pollution greatly affects the belowground faunal biodiversity and inhibits function of ecosystem to provide goods and services. In most of the cases, the population of soil fauna either declines or shows absence in the polluted sites. In contrast, population of certain fauna in soil increased in response to effluent pollution. Whereas few soil faunal population remained unaffected. These selective impacts of industrial effluents may be assigned to the differences in food availability, faunal and soil characteristics and their interactions in polluted pedoecosystem. Industrial effluents alter the pH, electrical conductivity, organic carbon, organic matter, ammonical nitrogen, nitrate nitrogen, total nitrogen, available phosphorus, soil respiration, soil dehydrogenase activity and carbon/nitrogen ratio (C/N ratio) of soils. Soil respiration and dehydrogenase activity decreased substantially indicating a remarkable decline in microbial activity in polluted soil. Effluent disposal also increases C/N ratio of polluted soil as compared to non-polluted one, which make the soil unfit for uptake of nutrients by plants. The pollution associated increase in C/N ratio and decrease in microbial activity may lead to a significant reduction in below-and above-ground biodiversity in long run. Since the soil fauna earthworms have a great ability to remove toxicants and mitigate soil pollution, they can be used for ameliorative purpose. The present observations embark the need to restore the soil faunal biodiversity by preventing disposal of untreated effluents in river, water bodies, soil and agricultural farms. In addition, bioremediation and other land reclamation technologies should be popularized to save soil system and environment. [ABSTRACT FROM AUTHOR]

The reductive conversion of CO2 into industrial products (e.g., oxalic acid, formic acid, methanol) can occur via aqueous CO2- as a transient intermediate. While the formation, structure, and reaction pathways of this radical anion have been modelled for decades using various spectroscopic and theoretical approaches, we present here, for the first time, a vibrational spectroscopic investigation in liquid water, using pulse radiolysis time-resolved resonance Raman spectroscopy for its preparation and observation. Excitation of the radical in resonance with its 235 nm absorption displays a transient Raman band at 1298 cm-1, attributed to the symmetric CO stretch, which is at ~45 cm-1 higher frequency than in inert matrices. Isotopic substitution at C (13CO2-) shifts the frequency downwards by 22 cm-1, which confirms its origin and the assignment. A Raman band of moderate intensity compared to the stronger 1298 cm-1 band also appears at 742 cm-1 and is assignable to the OCO bending mode. A reasonable resonance enhancement of this mode is possible only in a bent CO2-(C2v/Cs) geometry. These resonance Raman features suggest a strong solute-solvent interaction, the water molecules acting as constituents of the radical structure, rather than exerting a minor solvent perturbation. However, there is no evidence of the non-equivalence (Cs) of the two CO bonds. A surprising resonance Raman feature is the lack of overtones of the symmetric CO stretch, which we interpret due to the detachment of the electron from the CO2- moiety towards the solvation shell. Electron detachment occurs at the energies of 0.28 ± 0.03 eV or higher with respect to the zero point energy of the ground electronic state. The issue of acid-base equilibrium of the radical, which has been in contention for decades, as reflected in a wide variation in the reported pKa (-0.2 to 3.9), has been resolved. A value of 3.4 ± 0.2 measured in this work is consistent with the vibrational properties, bond structure, and charge distribution in aqueous CO2-. [ABSTRACT FROM AUTHOR]

A large amount of nanoparticles is manufactured globally and their uses are increasing geometrically. They have a wide range of applications in industries, science and technology. The other side of the coin is that they exert harmful effects on animal world. It led to the development of a new branch of biology i.e. nanotoxicology. Nanoparticles enter into the organisms and affect growth, survival, reproduction and feeding habits. Cellular metabolism is disrupted by their presence in biosystem. The main routes of nanoparticle entry are skin, gut and respiratory tract. Carbon nanotubes (CNTs) are one of the commonly used nanoparticles which are released into the aquatic environment through wastewater containing nanowaste and runoff from landfills. Toxicity bioassay tests of single and multiwalled carbon nanotubes have been conducted employing various fish species. Treatment of carbon nanotubes indicates high mucous secretion from gills and hyperactivity which gradually decline with increasing duration of exposure. Skin showed dark coloration in response to exposure of carbon nanotube. There occurs a gradual decrease in LC50 values as a function of exposure period indicating an enhancement in carbon nanotube toxicity. The pH, temperature and salinity affect the toxicity. Carbon nanotubes penetrate the cell membrane and ultimately cause cytoxicity, apoptosis, necrosis and nervous blockage leading to retardation in growth rate. They exert negative effects on growth and development of fish. CNTs inside the cell interact and damage nucleic acids and inhibit the protein synthesis leading to cell death by apoptosis and necrosis. Nanotubes decline various biochemical constituents in different organs of fish. The toxicity of nanoparticles also affects several metabolic enzymes. Decline in activity of cellular enzymes might disrupt intracellular metabolism and stimulates formation of reactive oxygen species (ROS) leading to oxidative stress.Ascorbic acid (vitamin C) is an antioxidant and provides protection to organisms against harmful effects of xenobiotics. Mitigation effect of ascorbic acid on CNT-induced changes in various biochemical constituents have been described. Ascorbic acid supplementation to carbon nanotube-intoxicated fish has been found to reduce the carbon nanotube toxicity. In view of available literatures it is suggested to minimize the use of carbon nanotubes in order to protect the health of fish resources [ABSTRACT FROM AUTHOR]

Structures with a sharp apex amplify an applied macroscopic field, FM, substantially and generate significant field electron emission (FE). The apex barrier field, Fa, is related to FM by the apex field enhancement factor (aFEF), γ a ≡ F a / F M . In this Letter, we provide a theoretical explanation for extremely high-effective FEFs ( 10 4 ≲ γ eff ≲ 10 5 ) recently extracted from an orthodoxy theory analysis of the emission current–voltage characteristics of looped carbon nanotube (CNT) fibers, making them promising candidates for FE applications. In this work, we found a dependence of γa on the geometrical parameters for an isolated conductive looped CNT fiber, modeled via the finite element technique. The aFEF of looped CNT fibers is found to scale as γ a = 2 + [ h f / r fiber ] [ ln (2 h / r fiber ) ] − 1 , where f ≡ 1 + θ [ r fiber / b ] α [ ln (2 h / r fiber ) − 1 ] , in which h is the height of a looped fiber standing on an emitter plate, b is its base length, rfiber is the radius of the fiber, and θ and α are fitting parameters that have a nonlinear dependence on the scaling parameter h/b. Our results show that the scaling law predicts that 10 ≲ γ a ≲ 100 for looped CNT fibers with parameters: 10 μm ≤ r fiber ≤ 100 μm, 0.4 ≤ h / b ≤ 2, and d / h ≥ 1 , where d is the distance between the apex of the looped fiber and the anode. However, scanning electron microscopy images reveal the presence of microfibrils protruding from the looped CNT fiber surface close to its apex. We show that the modeling of a combined two-stage structure (looped CNT fiber + fibrils) leads to aFEF values in excellent agreement with an orthodoxy theory analysis of FE experiments performed on these fibers. [ABSTRACT FROM AUTHOR]

We develop a kvector ·πvector +U formalism, where kvector is the carrier wave vector and πvector is the momentum operator in the presence of the spin-orbit interaction, within the effective mass representation of Luttinger and Kohn, which includes an effective magnetic field arising out of the mean field treated Hubbard onsite Coulomb repulsion. An effective equation of motion is obtained in the Luttinger-Kohn basis. As distinguished from hitherto used ordinary perturbation techniques in kvector ·πvector formalism, we use a Green's function perturbation technique to derive the energy of a carrier in this formalism. We apply the formalism to look for possibilities of a ferromagnetic transition in the diluted magnetic p-type Sn1-xGdxTe based on the Stoner criterion. The carrier electronic structure developed for p-SnTe using the kvector ·πvector method is extended to p-type Sn1-xGdxTe. The Fermi energy, density of states, effective g-factor, and the effective mass are calculated as functions of hole density. Our results show that there could be a hole-induced transition to a ferromagnetic state at high hole concentrations and low temperatures in the dilute limit of Gd impurities. [ABSTRACT FROM AUTHOR]

Nanotechnology has tremendous potential to improve many sectors of science and technology such as industries, physical, chemical and biological engineering, consumer products, medical, environmental and agricultural sciences and so on. Due to specific physicochemical properties, nanoparticles behave differently from bulk materials. The extremely small size of nanoparticle enhances surface area-to-volume ratio making it highly reactive. Such unique and advantageous properties of NPs increase their applications in various fields. Huge amount of NPs is produced annually world-wide. The immense and diversified uses impose potential danger on environment and organisms. Toxicological studies of nanoparticles have opened a new branch of science i.e. nanotoxicology. There are three routes of entry of nanoparticles inside the body viz. inhalation, skin and gastrointestinal tract. Since the earthworm is a megadrile resource of pedoecosystem and occupies an important tropic level, many studies have focussed on this below-ground organism. Earthworms respire through skin and ingest soil so NPs enter through skin and/or gastrointestinal tract. Nanoparticle toxicity depends on particle size, shape, quality, coating, chemical properties and concentration of NPs as well as nature of encountering organisms. Nanoparticles have negative impact on survival, growth, development, reproduction and biochemical machinery of animals including earthworms. Literatures revealed that the behaviour, survival, biomass and fecundity of earthworm are greatly affected by nanoparticle exposure. NPs penetrate the cell and its organelles and disrupt cellular metabolism which eventually lead to cell death. In addition, NPs may break DNA helices, disrupt gene expression and impair mitochondrial functions. They generate reactive oxygen species in cells and cause oxidative stress. It embarks the need to ameliorate toxicological effects of nanoparticles through antioxidant-rich food, which can inhibit the process of oxidation and prevent formation of free radicals. In the present scenario, wide and indiscriminate use of nanoparticles should be avoided or minimized as far as possible to protect the health of animal world. [ABSTRACT FROM AUTHOR]

The toxic impacts of zinc oxide nanoparticles (ZnO NPs) on reproductive potential of the earthworm, Eisenia fetida were studied in relation to varying temperature and pH in natural (NS) and artificial substrate (AS). The ZnO NPs decreased cocoon production, hatching and rate of reproduction as a function of increasing concentration, temperature and exposure period. The gradation of temperature and pH to get a better reproductive potential was found to be 25°C > 20°C > 30°C and 6:5 > 7:5 > 5:5, respectively. Cocoon production was higher in NS than the AS. It may be due to sufficient food availability in NS. Survival of adult worms was decreased with increase in ZnO NPs and exposure period. The rate of reproduction was signi ficantly higher in NS as compared to AS at 25°C. The present findings suggested that ZnO NPs retard the reproductive potential of E. fetida and may also be hazardous to pedoecosystem and fauna living there in. Temperature of 25°C, pH 6.5 and NS as vermibed were the most suitable conditions to maintain worthy rate of reproduction and reduce ZnO NPs toxicity. [ABSTRACT FROM AUTHOR]

This paper explores the preparation of two-dimensional (2D) antimony (Sb) nanoribbon and explores the electrical, thermal conductivity of armchair and zigzag structures. It employs the weak Vander Waal forces for estimating the long range intermolecular interactions. In present work, the zigzag, armchair structures of Sb are analyzed and observed that the armchair predict semiconductoring nature and zigzag predict metallic structure. In the same context, the density of states (DOS), electrical conductivity and thermal conductivity of the armchair and zigzag structure is calculated. All the calculations are based on first principle theory and maximally localized wannier functions (MLWF) using Quantum Espresso and Wannier90 simulation tools respectively. The thermal as well as electrical conductivity is analyzed at three diverse temperatures 300K, 400K and 700K respectively for armchair and zigzag nanoribbon structure. From the present work, it is concluded that Sb armchair, zigzag structure results in better performance at higher temperature compared with its bulk counterpart. [ABSTRACT FROM AUTHOR]

The reactions of the aqueous proton with the zwitterionic p-aminophenoxyl radical in strongly basic to extremely acidic aqueous solutions have been investigated using time-resolved resonance Raman spectroscopy. The dynamic stability of the different protonation forms of the radical, observed on the microsecond time scale in this work, has been achieved by controlling the proton exchange rate in water. In strongly acidic solutions we observe a rare ring-H+ bonded dication species, a key intermediate in the amine hydrolysis. The neutral p-aminophenoxyl radical undergoes NH2-deprotonation in strongly basic aqueous solutions, which has no analogues in closed-shell amines. [ABSTRACT FROM AUTHOR]

The electronic structure of aqueous p-aminophenoxyl radical (H[sub 2]NPhO[sup ...]) has been examined by time-resolved resonance Raman spectroscopy and ab initio and density functional theories. The effects of hydrogen bonding and solvent reaction field on polarity of the radical have been visualized in terms of simple models. Calculations predict the dipole moment of the radical in its ground electronic state (²B[sub 1]) to increase by 8(±2) D and the difference between the CN and CO bond lengths to decrease by ∼0.05 Å from gas phase to aqueous solution. This profound hydration effect converts the structure and chemical properties of H[sub 2]NPhO[sup ...] from a substituted phenoxyl radical in the gas phase to a semiquinone-like radical in water. The observation of vibrational modes enhanced in Raman by a non-Franck-Condon vibronic coupling mechanism has led to the identification of two very weakly absorbing electronic states of ²A[sub 2] symmetry in the 340-390 nm region, which borrow transition moment from close by strongly allowed electronic states of ²B[sub 1] symmetry at lower (∼440 nm) and higher (∼320 nm) energies. One of these transitions is parity forbidden (²B[sub 2g] &rlarr; ²B[sub 1g]) in p-benzosemiquinone radical anion (PhO[sub 2, sup -·]) and p-phenylenediamine radical cation (Ph(NH[sub 2])[sub 2, sup +·]) and this is the first experimental evidence on energy location (3.44 eV) of this transition in an isoelectronic radical. The experiment and theory are combined to estimate the CO and CN bond lengths in H[sub 2]NPhO[sup ·] as ∼1.263 and ∼1.34 Å, respectively, in liquid water and ∼1.245 and ∼1.37 Å in the gas phase. [ABSTRACT FROM AUTHOR]

The use of nanoparticles is growing exponentially, but they are hazardous to biological world. Nanoparticles released in aquatic environment may affect cellular and biochemical functions and in turn, reduce fish productivity. Carbon nanotube is a nanomaterial which is mainly used for water purification, but they may cause toxicity in aquatic species. Hence the effects of carbon nanotubes on some metabolic enzymes of the freshwater fish Channa punctatus were investigated. Treatment of carbon nanotubes declined the activity of succinate dehydrogenase (SDH), cytoplasmic malate dehydrogenase (cMDH) and lactate dehydrogenase (LDH) in liver, brain, gill and kidney of the fish. Maximum decrease in SDH activity was in gill followed by kidney, brain and liver. The decline in cMDH activity was maximum in kidney and minimum in brain. Likewise, reduction in LDH activity was maximum in brain and minimum in gill. The tissue-specific reductions in activity of enzymes may be assigned to the differences in nature of different organs. Among these enzymes maximum decline was in activity of cMDH reflecting inhibition in gluconeogenic and lipogenic capacity of fish. The effects of carbon nanotubes on activity of these metabolic enzymes were concentration-dependent. The present findings indicated that the carbon nanotubes are toxic to the cellular and subcellular enzymes and their uses should be restricted to save the health of fish. [ABSTRACT FROM AUTHOR]

Nanotoxicology is a newly emerged branch dealing with the study of effects of nanoparticles or nanomaterials on organisms. Nanoparticles are extremely small in size (1-100 nm) and highly reactive to cause toxicity in biological system. Silver nanoparticle (AgNP) is widely used and its market is increasing regularly imposing threats to man and environment. Most of the industrial and household wastes reach to aquatic ecosystem and affect animals living there in. Fish is most vulnerable aquatic bioresource to toxicants. Different studies have shown that intense and indiscriminate use of toxic chemicals including nanoparticles are harmful to biological world. Various scientists studied the toxic behavior of silver nanoparticles and described their influences on different structural and functional aspects of organisms. Silver nanoparticles (AgNPs) alter the behavior and retard the growth and development of fish. They adversely affect the haematological and biochemical parameters. Impacts of silver nanoparticles on histoarchitechural and enzymological changes have been studied. Therefore, the existing reports clearly alarm to minimize the use of silver nanoparticles in order to save aquatic bioresourses. [ABSTRACT FROM AUTHOR]

Nanoparticles released in aquatic environment may effect biochemical constituents and in turn, reduce fish productivity. Hence, the effects of carbon nanotube on profile of DNA, RNA, RNA/DNA ratio, protein, glucose, glycogen, cholesterol and lipid of liver, brain, gill and kidney of the freshwater fish Channa punctatus were investigated. Treatment of carbon nanotube declined the DNA, RNA, protein, glucose, glycogen, cholesterol and total lipid in liver, brain, gill and kidney of the fish. But the decline in RNA/DNA ratio was insignificant. Maximum decrease in DNA content was in kidney followed by brain and gill. The decline in RNA content was maximum in kidney and minimum in liver. Likewise, reduction in protein profile was maximum in kidney and minimum in brain. Maximum decrease in glucose content was obtained in liver and kidney in response to 300 ppm carbon nanotube treatment. However, minimum decrease was observed in gill after treatment of 100 ppm nanotube. Maximum decrease in glycogen content was found in kidney in response to carbon nanotube, while minimum decrease was observed in liver. Likewise, the effects of carbon nanotube on cholesterol and total lipid were maximum in gill and liver respectively. The tissue-specific reductions in macromolecular contents may be assigned to the differences in nature of different organs. The effects of carbon nanotube on DNA, RNA, protein, glucose, glycogen, cholesterol and total lipid contents were concentration-dependent. The present findings indicated that the carbon nanotubes are toxic to the biochemical machinery and their uses should be restricted to save the health of aquatic faunal resources. [ABSTRACT FROM AUTHOR]

Extensive use of nanoparticles at commercial level inevitably enhances their release into the environment and effects terrestrial as well as aquatic organisms. The entry of nanoparticles in soil ecosystem causes toxicity in animals living there in. So an experiment was conducted to study the toxicological effects of zinc oxide nanoparticles (ZnO NPs) on some biochemical constituents of the earthworm, Eisenia fetida. The individuals of the earthworm were exposed to different concentrations of ZnO NPs for two weeks. The sublethal concentrations of ZnO NPs significantly declined the DNA, RNA and protein contents. Maximum reduction was observed in protein, while minimum decline was in RNA/DNA ratio. Similarly, the treatment of ZnO NPs decreased the carbohydrate and lipid contents in E. fetida. The decrease in carbohydrate content was more as compared to decline in lipid. The ZnO NPs significantly declined the activity of malate dehydrogenase (MDH) and lactate dehydrogenase (LDH). The reduction in activity was more in MDH as compared to LDH indicating greater impact on aerobic capacity of the earthworm. Nanoparticle associated decrease in dehydrogenase activity reflected inhibition in metabolic functions. The effects of ZnO NPs on biochemical constituents of earthworm were concentration-dependent. It suggested that the use of nanoparticles should be minimized as far as possible to protect metabolism and health of earthworms. [ABSTRACT FROM AUTHOR]

Industrial and household waste products are dumped into water bodies, which adversely affect organisms inaquatic ecosystem. Currently the uses of various types of nanomaterials have dramatically increased on a large scale. Silver nanoparticle is one of the most commonly used nanomaterials which may influence cellular physiology of fish. So the effectsof silver nanoparticles (AgNPs) onhistoarchitecture andacid (ACP) andalkaline (ALP) phosphatase activitieswere studied in the freshwater food fish, Channapunctatus. Exposure of AgNPs to the fish produced dark apperence indicating nanomaterials bioaccumulation in tissues. The histological alterations like deformities and damages in tissues as well as necrosis were observed in different organs of the fish exposed to 1 to 3ppm of silver nanoparticles. Structural deformities and damages were AgNP-concentration dependent. The treatment of 1, 2 and 3ppm of silver nanoparticles (AgNPs) showed increase in ACP and ALP activities in liver, gill, stomach and intestine of the fish. This increase in phosphatase activity was also AgNP-concentration dependent. Virtually the silver nanoparticles induced the degradative activities in cells and also deformed and damaged various tissues badly. Hence they are harmful to fish and their uses should be minimized. [ABSTRACT FROM AUTHOR]

This studydeals with the effects of disposal of industrial effluents on soilfaunal biodiversityaround Jodhpur city of Rajasthan in India. A lot of industrial units are working in Jodhpur.These industries release their effluents in water bodies and on land directly or indirectly. Effluents cause detrimental effects on soil system and fauna inhabiting there in are seriously affected. Twelve different polluted sites were chosen along the bank of river Jojari for faunal collection. A total 22 genera of different groups of soil fauna viz., earthworms, beetles, spiders, termites, millipedes, centipedes, mites, ants and insect larvae were recorded. Many annelids and arthropodswere affected with hazardous industrial effluents in polluted sites as compared to the non-polluted one. Soil fauna were more affected near to the disposal sites as compared to the distant places. Thus industrial pollution is greatly affecting the below-ground faunal biodiversity which may hamper function of ecosystem to provide goods and services. In most of the cases, the population of soil fauna either declined or showed absence in the polluted sites. In contrast, population of certain fauna in soil increased in response to effluent pollution. Whereas few soil faunal population remained unaffected. These selective impacts of industrial effluents may be assigned to the differences in food availability, faunal and soil characteristics and their interactions in polluted pedoecosystem. [ABSTRACT FROM AUTHOR]

The vibrational and electronic structures of p-phenylenediamine radical cation have been studied using time-resolved resonance Raman spectroscopy and molecular orbital calculations. The Raman spectra in aqueous solution show striking variations in intensity profile when excitation is varied from 340 to 480 nm. Excitation in resonance with the 460–480 nm absorption shows enhancement of only totally symmetric vibrations. Most prominent are the δNH2 scissor mode at 1658 cm-1 and the Wilson modes ν8a (CC stretch) at 1644 cm-1, ν7a (CN stretch) at 1423 cm-1, and ν9a (CH bend) at 1184 cm-1. Also observed are ν1 (ring breathe) at 840 cm-1 and ν6a (CCC bend) at 467 cm-1. With excitation in the 340–410 nm region the ν1 band becomes relatively stronger and an additional band at 1524 cm-1 appears. This latter band, which dominates the spectrum at 360 nm, is assigned to the nontotally symmetric vibration ν8b (CC stretch) having b3g symmetry that gains intensity through vibronic coupling. Raman spectra of ring- and amine-deuterated radicals allow distinction of overtone and combination bands enhanced by Fermi resonance from fundamentals due to δNH2 and ν8a (CC stretch) modes in the 1600–1700 cm-1 region. The theoretical calculations show reasonable agreement with the observed vibrational frequencies and lead to detailed information on the bond structure and normal modes of the radical. The calculated CN bond lengths of 1.33 Å are intermediate between lengths typical of single and double bonds in aromatic amines. The calculations also allow interpretation of the experimental absorption spectrum. The broad medium intensity absorption peaked at 460 nm with a shoulder at 480 nm is assigned to a 2B3u ←2B2g transition, the very weak 360 nm absorption to 2Au ← 2B2g and the very strong ∼325 nm absorption to a higher 2B3u ← 2B2g.Calculations with the simple relation Ik∝... [ABSTRACT FROM AUTHOR]

The time-resolved Tn←T1 resonance Raman spectra of quinoline (1-azanaphthalene), isoquinoline (2-azanaphthalene), quinoxaline (1,4-diazanaphthalene), and quinazoline (1,3-diazanaphthalene) molecules in cyclohexane solution are reported, and vibrational assignments and structural implications are discussed. In each of the four compounds, the most resonance enhanced Raman band lies in the 1340–1270 cm-1 region and corresponds to nuclear displacements involving in-plane stretching motions of the CC and CN bonds. In diazanaphthalenes, drop in the frequency of this vibration on S0 to T1 excitation (97 cm-1 in quinoxaline, 76 cm-1 in quinazoline) is observed to be higher than in azanaphthalenes (31 cm-1 in quinoline, 58 cm-1 in isoquinoline) implying pronounced elongation of the CN bonds, in comparison to the CC bonds, in the T1 states. The T1 Raman spectra of azanaphthalenes, in contrast to naphthalene, are observed to exhibit significant solvent dependency. [ABSTRACT FROM AUTHOR]

We report, in this paper, submicrosecond time resolved resonance Raman spectra of anilino radical and its radical cation as observed in pulse radiolytic studies of the oxidation of aniline in aqueous solution. By excitation in resonance with the broad and weak electronic transition of anilino radical at 400 nm (ε∼1250 M-1 cm-1) we have observed, for the first time, the vibrational features of this radical. The Wilson ν8a ring stretching mode at 1560 cm-1 is most strongly resonance enhanced. The ν7a CN stretching band at 1505 cm-1, which is shifted to higher frequency by 231 cm-1 with respect to aniline, is also prominent. The frequency of this latter mode indicates that the CN bond in the radical has considerable double bond character. The Raman spectrum of aniline radical cation, excited in resonance with the ∼425 nm electronic absorption (ε∼4000 M-1 cm-1), shows features which are similar to phenoxyl radical. Most of the observed frequencies of this radical in solution are in good agreement with vibrational energies determined by recent laser photoelectron spectroscopic studies in the vapor phase. The bands most strongly enhanced in the resonance Raman spectrum are, however, weak in the photoelectron spectrum. While the vibrational frequencies observed for anilino radical and its isoelectronic cation are quite similar, the resonance enhancement patterns are very different. In particular the ν14 b2 mode of anilino radical observed at 1324 cm-1 is highly resonance enhanced because of strong vibronic coupling between the 400 nm 2A2–2B1 and the higher 2B1–2B1 electronic transitions. [ABSTRACT FROM AUTHOR]

White grubs are polyphagous subterranean insect pests which have recently emerged as a major threat to sugarcane cultivation. For effective management of these pests in sugarcane, studies were undertaken to evaluate various locally isolated as well as commercially available microbial biocontrol agents, entomopathogenic nematodes and novel chemical pesticides against white grubs. Attempts were made to isolate effective bio-agents associated with white grubs in indo-gangetic plains of India. Altogether, nine local bacterial isolates associated with infected white grubs were isolated and tested for their bio-efficacy under laboratory condition. However, none of the isolates were found effective against the predominant species, Holotrichia consanguinea. Hence, attempt was made to assess the field efficacy of already available five microbial bio-agents, viz., Metarhizium anisopliae, Beauveria bassiana, Bacillus cereus strain WGPSB-2, Heterorhabditis indica, Steinernema carpocapsae and three insecticides, viz., Chlorantraniliprole 0.4 G, Fipronil + Imidacloprid 80 G and Chlorpyriphos 10 G at their recommended doses. Results of the experiments conducted for 2 years under randomized block design revealed that treatment of Bacillus cereus strain WGPSB-2 @10 kg/ha (1 × 1013 cfu/ha) could reduce the white grub damage to the extent of 59.8%, while other bio-agents could reduce the damage in the range of 24.3-39.5% over untreated control. All the insecticides were found effective in reducing white grub damage, and in most of the observations, difference in reduction in the white grub damage was statistically non-significant. However, Chlorantraniliprole 0.4 G @ 20 kg/ha was most effective, which could reduce the grub damage to the extent of 89.10% over untreated control. [ABSTRACT FROM AUTHOR]

Reducing the emission of secondary electrons from materials is critical to improved efficiency and increased performance in high power vacuum electronics. A new mathematical expression for the secondary emission yield (SEY) as a function of the impact voltage up to a maximum of 5 kilovolts is proposed which is an extension of a formula first suggested by Vaughan. The new analytical fit and Vaughan’s fit are compared with SEY experimental data reported by others and measured by our group. The new analytical expression gives good fits to SEY experimental data in all cases, even when the SEY maximum is either slightly larger or below unity, two situations for which Vaughan’s fit is either inadequate or inapplicable. [ABSTRACT FROM AUTHOR]

This paper is based on industrial survey conducted around Jodhpur city of Rajasthan in India. It was found that there are many source points of effluent disposal from different industrial units. Most of the waste disposal sites are situated along river Jojari. It was observed that most of the effluents are released into this river directly or after incomplete treatment, which may make soil brittle, infertile, barren and fluffy. Apart from this, it smells and may cause adverse effects on faunal communities. Not only small animals but large mammals were also found dead around the polluted sites. Chemicals released from these industries may include toxic heavy metals and organic substances. [ABSTRACT FROM AUTHOR]

Nanoparticles influence fauna, inhabiting soil ecosystem. The properties of bedding materials decide survival and growth of juveniles of earthworm. In the present study, we examined the effects of zinc oxide nanoparticles (ZnO NPs) on survival and growth of juvenile of the earthworm, Eisenia fetida in two different substrates for 28 days. Exposure of juveniles of earthworm to ZnO NPs in artificial substrate declined more body weight and length gain as compared to the natural substrate. Similarly, nanoparticles reduced increase in specific growth rate (SGR). Survival of juveniles in artificial substrate decreasedmore as compared to natural substrate,with increase in nanoparticle concentration. Thus ZnO NPs effectively reduced growth and survival in artificial substrate, while natural substrate (cowdung + horse manure) provided better and suitable environment for growth and survival of juveniles of earthworms. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) have commercial uses but they may produce toxic effects in organisms inhabiting soil ecosystem. Hence, assessment of toxicity in soil organism is important. To assess toxicities, individuals of the earthworm Eisenia fetida were treated with varying concentrations of ZnO NPs for 1 to 14 days. Earthworm mortality was related to the concentration of ZnO NPs. The median lethal concentration (LC50) of ZnO NPs for different time durations was estimated. The LC50 values gradually decreased with exposure period. Thus there was an increase in toxicity of ZnO NPs as a function of increasing duration. The effects of pH and temperature on median lethal concentration of ZnO NPs were also determined. The LC50 value decreased if pH was higher and lower than 6.5 - 7. Similarly, the LC50 value declined below and above 25°C temperature. There were also some behavioral changes including dermal mucus secretion and alteration in coloration of earthworm in response to exposure of ZnO NPs. The study suggests that the use of zinc oxide nanoparticles should be reduced to protect the health of earthworms. [ABSTRACT FROM AUTHOR]

Carbon nanotube are mainly utilized for water purification, but they may be toxic to aquatic organisms including fishes, crustaceans etc. Hence, the present study was conducted to investigate the effects of multiwalled carbon nanotube (MWCNT) on growth, survival and feed intake of fingerlings of a fresh water fish. Results showed that initially no mortality observed at 100 mg × L-1 of nanotube concentration up to 7 days. Later on mortality was observed in all test groups. There were reductions in specific growth rate, mass and length of fish in response to treatment of nanotube. These declines were concentration dependent. Survival of fingerlings decreased with increasing concentration of MWCNT. This suggests that there should be limited use of carbon nanotube in order to avoid its toxicological effects on piscine system. [ABSTRACT FROM AUTHOR]

The use of nanomaterial is growing exponentially but they are hazardous to terrestrial as well as aquatic organisms. These materials can cause a range of sub lethal effects in fish. Carbon nanotube is a nanomaterial which is utilized for water purification, but they may cause toxicity in aquatic species. Hence the present study was conducted to investigate the toxicological effect of carbon nanotube in fresh water fish Channa punctatus. The median lethal concentrations (LC50s) of carbon nanotube for different duration were estimated. Individuals of fish were treated with different concentrations of carbon nanotube for 28 days. In this investigation, we observed visual changes in pigmentation and mucous secretion from the fish. There was no mortality at 200 mg x L-1 carbon nanotube exposure for 96 hr. So higher concentrations were used for determination of LC50. The LC50 values gradually declined as a function of exposure period from one to twenty eight days. It suggests increase in toxicity of carbon nanotube with increasing period of exposure. The influences of temperature, pH, and salinity on median lethal concentration of carbon nanotube for C. punctatus were also observed. [ABSTRACT FROM AUTHOR]

Nanoparticles may harm the environment and organisms living there in. Silver nanoparticles are widely used nanochemical exerting adverse effects on animal system. So the median lethal concentration (LC50) of silver nanoparticle for the freshwater food fish, Channa punctatus was determined. It was found that as the time increases the toxicity also increases, while the LC50 value decreases. The effects of temperature, pH and salinity on LC50 were determined in response to silver nanoparticle exposure to the freshwater fish. Silver nanoparticle associated changes in behavior, skin colour, mucus secretion and sometimes bleeding were also noticed. Therefore, it is suggested that the use of silver nanoparticles should be minimized to protect fish resources and aquatic environment. [ABSTRACT FROM AUTHOR]

We derive the many-body theory of the effective mass in the effective mass represen- tation (EMR). In the EMR, we need to solve the equation of motion of an electron in the presence of electron{electron interactions, where the wavefunction is expanded over a complete set of Luttinger-Kohn wavefunctions. We use the Luttinger-Ward thermo- dynamic potential and the Green's function perturbation to derive an expression for the band effective mass by taking into account the electron{electron interactions. Both quasi-particle and the correlation contributions are considered. We show that had we considered only the quasi-particle contribution, we would have missed important cancel- lations. Thus the correlated motion of electrons has important effects in the renormal- ization of the effective mass. Considering the exchange self-energy in the band model, we derive a tractable expression for the band effective mass. We apply the theory to n-type degenerate semiconductors, PbTe and SnTe, and analyze the impact of the theory on the anisotropic effective mass of the conduction bands in these systems. [ABSTRACT FROM AUTHOR]

This paper presents a compact pentagon shaped monopole microstrip patch antenna, which has been modified to improve its performance. All sides of pentagon patch are truncated and offset feeding is provided to enhance the bandwidth. Defected Ground Structure (DGS) is used which has two rectangular slots of quarter wavelength opposite to each other, and a notch beneath the feedline on the partial ground plane. These slots on the ground plane improves the gain and return loss of the design. The analysis is performed and results are obtained using Ansoft High Frequency Structure Simulator (HFSS). Various parameters which include impedance bandwidth, gain, efficiency, radiation pattern and current distribution of the antenna are studied. The performance of proposed antenna is compared with classical antenna design, both having same operating frequency of 7.4 GHz. Results obtained from the simulation shows impedance bandwidth of 16.65 (3.85-20.5 GHz) GHz, which is 60% enhanced bandwidth as compared to classical antenna, maximum gain of 6.85 dB at 14.35 GHz, peak return loss of -41.6 dB at 7.2 Ghz and good radiation pattern is observed at frequencies of 7.34, 10.4, and 19 GHz. Application of this antenna covers Ultrawide Band (UWB), X Band and Ku Band, and it can be used efficiently for mobile or satellite communication. [ABSTRACT FROM AUTHOR]

Resonance Raman spectra of the photoexcited lowest triplet (3B+2u) state of naphthalene (N-h8 and N-d8), observed in solution by time-resolved technique, are reported. Eight Raman bands (396, 496, 741, 958, 1337, 1395, 1440, and 2676 cm-1) have been observed in N-h8 and ten (479, 690, 754, 1005, 1142, 1281, 1356, 2491, 2638, and 2714 cm-1) in N-d8. Vibrational assignments are briefly discussed. [ABSTRACT FROM AUTHOR]

Presents a study which employed local spin-density theory and the linear combination of Gaussian orbitals method to compute the band structure and ferromagnetic moment of nonequilibrium phases of several transition metals. Studies on magnetism in nonequilibrium phases of transition metals; Description of the nonequilibrium bcc and fcc phases for manganese; Characteristics of the room-temperature equilibrium lattice constant of bcc niobium.

Discusses the theory of magnetization in IV-VI based diluted magnetic semiconductors (DMS). Contribution of lattice diamagnetism to the magnetization; Properties exhibited by DMS; Relative strengths of the contributions to the magnetization.