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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]

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]

Research is done on the kinetic and structural properties of the intrmolecular sulfur--nitrogen bond in aqueous 3-(methylthio)propylamine radical cation which s examined as a model for the cyclized radical state of L-methionine, an essential aminoacid in protein biosysthesis. In conclusion, the hypothetical intermediate, SNOH., presumed to be formed on oxidation of methionine and derivates in basic solutions, has been identified with the .S NH.-species.