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In mitochondria, the detoxification of molar excess H2S as polysulfide proceeded via an oxidation process promoted by Cu/Zn containing superoxide dismutase (SOD1) enzyme, which has been very recently reported as the alternative enzyme for cytosolic H2S oxidation. Herein, we present Ni(II) complexes bearing the terminal SH group as a synthetic functional analogue for the sulfide oxidase function of SOD1. Synthesis, crystal structure and complete spectroscopic characterization of two sets of complexes, [NiLOMe/tBu(PPh3)] (2OMe/tBu) and tetraethyl salt of [NiLOMe/tBu(SH)]−1 (3OMe/tBu), were described (LOMe = (E)-2-methoxy-6-(((2-sulfidophenyl)imino)methyl)phenolate and LtBu = (E)-2,4-di-tert-butyl-6-(((2-sulfidophenyl)imino)methyl)phenolate). Under anaerobic conditions, 3OMe/tBu responded to a catalytic sulfur atom transfer (SAT) reaction with PPh3 to produce SPPh3. The SAT reaction was analyzed using detailed studies of 1H and 31P NMR spectra. Finally, the SAT reactivity pattern was compared with the same in the native enzyme of SOD1. [ABSTRACT FROM AUTHOR]

AbstractIncreasing industrialization and urbanization have contributed to a significant rise in wastewater discharge and exerted extensive pressure on the existing natural energy resources. Microbial fuel cell (MFC) is a sustainable technology that utilizes wastewater for electricity generation. MFC comprises a bioelectrochemical system employing electroactive biofilms of several aerobic and anaerobic bacteria, such as Geobacter sulfurreducens, Shewanella oneidensis, Pseudomonas aeruginosa, and Ochrobacterum pseudiintermedium. Since the electroactive biofilms constitute a vital part of the MFC, it is crucial to understand the biofilm-mediated pollutant metabolism and electron transfer mechanisms. Engineering electroactive biofilm communities for improved biofilm formation and extracellular polymeric substances (EPS) secretion can positively impact the bioelectrochemical system and improve fuel cell performance. This review article summarizes the role of electroactive bacterial communities in MFC for wastewater treatment and bioelectricity generation. A significant focus has been laid on understanding the composition, structure, and function of electroactive biofilms in MFC. Various electron transport mechanisms, including direct electron transfer (DET), indirect electron transfer (IET), and long-distance electron transfer (LDET), have been discussed. A detailed summary of the optimization of process parameters and genetic engineering strategies for improving the performance of MFC has been provided. Lastly, the applications of MFC for wastewater treatment, bioelectricity generation, and biosensor development have been reviewed. [ABSTRACT FROM AUTHOR]

Sometimes unusual redox chemistry and modulation of enzyme activity Cu‐proteins can be encountered by the presence of a trace amount of Cu−Tris interaction (Tris‐(hydroxymethyl) aminomethane) during vitro studies. Herein, we addressed a redox chemistry of CuII−Tris with variable stoichiometric ratios in the presence of ascorbic acid (H2A) and O2. The redox chemistry of Bs3 (Cu : Tris; 1 : 3) with H2A/O2 was passed through several intermediates with progress on time yielding initially yellow precipitate, (Yp3), then green solution, (Gs3) and finally cyan solution (Cs3). The UV‐Vis spectra of Bs3, Gs3 and Cs3 displayed peaks at 640, 690 and 710 nm respectively suggesting CuII. The redox potential of CuII/CuI in Bs3, Gs3 and Cs3 were −0.18 V, −0.15 V and −0.19 V (vs. Ag/AgCl) respectively. The EPR spectrum of Bs3 showed an axial signal with g∥,⊥=2.483/2.105&A∥=160×10−4 cm−1 whereas Gs3 and Cs3 showed rhombic signal with g1,2,3=2.302/2.063/2.018&A∥=177×10−4 cm−1 and g1,2,3=2.274/2.064/2.016&A∥=164×10−4 cm−1 respectively suggesting a distorted tetragonal geometry. ESI−MS data indicated the probable composition of Bs2‐Bs5, Gs3 and Cs3 in solution. Integration of all spectroscopies data demonstrated the probable composition and redox mechanism. [ABSTRACT FROM AUTHOR]

Machine learning (ML) has been used for classification of heart diseases for almost a decade, although understanding of the internal working of the black boxes, i.e., non-interpretable models, remain a demanding problem. Another major challenge in such ML models is the curse of dimensionality leading to resource intensive classification using the comprehensive set of feature vector (CFV). This study focuses on dimensionality reduction using explainable artificial intelligence, without negotiating on accuracy for heart disease classification. Four explainable ML models, using SHAP, were used for classification which reflected the feature contributions (FC) and feature weights (FW) for each feature in the CFV for generating the final results. FC and FW were taken into account in generating the reduced dimensional feature subset (FS). The findings of the study are as follows: (a) XGBoost classifies heart diseases best with explanations, with an increase in 2% in model accuracy over existing best proposals, (b) explainable classification using FS exhibits better accuracy than most of the literary proposals, and (c) with the increase in explainability, accuracy can be preserved using XGBoost classifier for classifying heart diseases, and (d) the top four features responsible for diagnosis of heart disease have been exhibited which have common occurrences in all the explanations reflected by the five explainable techniques used on XGBoost classifier based on feature contributions. To the best of our knowledge, this is first attempt to explain XGBoost classification for diagnosis of heart diseases using five explainable techniques. [ABSTRACT FROM AUTHOR]

Flexible and foldable paper‐based thermoelectric generators (PTEGs) have drawn industrial attention due to the wide applications in heat energy harvesting and sensing. Herein, optimization of the output performances of flexible and hybrid inorganic–organic PTEGs fabricated on stationery paper substrates from poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) and graphite as p‐type and n‐type materials, respectively, is presented. By choosing simplistic processes such as polyethyleneimine (PEI)‐treated graphite pencil traces and brush‐painted PEDOT:PSS films, robust and sustainable PTEG devices are fabricated. It is first time shown that different qualities of stationery papers can have significant impact on the output performance of PTEGs, attributed to their variance in substrate roughness. Thus, output powers of ≈1.93 and ≈0.68 nW for ΔT = 70 K are obtained for TE generators prepared from emery and office paper legs (four‐pair assembled on Kapton), respectively, suggesting emery paper to have significant better performance. Transient flexibility and fatigue of each device type are also tested where emery paper–based PTEG appears to be more robust. A detail comparison of the device performances on the different types of paper substrates are exclusively presented experimentally and thereafter computationally validated by COMSOL modeling to predictably control and enhance the output performance of reported PTEGs. [ABSTRACT FROM AUTHOR]

Acid-tolerant bacteria such as Streptococcus mutans, Acidobacterium capsulatum, Escherichia coli, and Propionibacterium acidipropionici have developed several survival mechanisms to sustain themselves in various acid stress conditions. Some bacteria survive by minor changes in the environmental pH. In contrast, few others adapt different acid tolerance mechanisms, including amino acid decarboxylase acid resistance systems, mainly glutamate-dependent acid resistance (GDAR) and arginine-dependent acid resistance (ADAR) systems. The cellular mechanisms of acid tolerance include cell membrane alteration in Acidithiobacillus thioxidans, proton elimination by F1–F0–ATPase in Streptococcus pyogenes, biofilm formation in Pseudomonas aeruginosa, cytoplasmic urease activity in Streptococcus mutans, synthesis of the protective cloud of ammonia, and protection or repair of macromolecules in Bacillus caldontenax. Apart from cellular mechanisms, there are several acid-tolerant genes such as gadA, gadB, adiA, adiC, cadA, cadB, cadC, speF, and potE that help the bacteria to tolerate the acidic environment. This acid tolerance behavior provides new and broad prospects for different industrial applications and the bioremediation of environmental pollutants. The development of engineered strains with acid-tolerant genes may improve the efficiency of the transgenic bacteria in the treatment of acidic industrial effluents. Key points: • Bacteria tolerate the acidic stress by methylating unsaturated phospholipid tail • The activity of decarboxylase systems for acid tolerance depends on pH • Genetic manipulation of acid-tolerant genes improves acid tolerance by the bacteria [ABSTRACT FROM AUTHOR]

We investigate how the Raychaudhuri equation behaves in the k‐essence geometry. As far as we are concerned, both the early and current epochs of the universe are relevant to the k‐essence theory. Here, we have studied the k‐essence geometry using the Dirac‐Born‐Infeld (DBI) variety of non‐standard action. The corresponding k‐essence emergent spacetime is not conformally equivalent to the usual gravitational metric. We assume that the background gravitational metric is of the Friedmann‐Lemaitre‐Robertson‐Walker (FLRW) type in this case. We have found that both the conditional singular and non‐singular cosmological models of the universe through the modified Raychaudhuri equation are possible where we have used the spacetime as the flat k‐essence emergent FLRW‐type. We have also addressed the Focusing theorem and conditional caustic universe construction. These conditional effects are caused by the additional interactions that arise as a result of the coupling that exists between gravity and the k‐essence scalar field. [ABSTRACT FROM AUTHOR]

In the civil infrastructure, the structures made up of tubular sections played an important role due to an economic point of view, lower self-weight, and stability against functional loads. The periodical maintenance or inspection of the structure is mandatory nowadays to achieve the potential utilization of the structural system. In this study, an experimental, numerical, and analytical study is carried out to investigate the structural fault and its severity in a tubular rectangular beam made up of structural steel. Modal parameters are extracted with the help of a dynamic data logger (B&K) by exciting an impact hammer on model structure and extracting a data with a set of unidirectional accelerometers. First, two displacement mode shapes are extracted using obtained modal parameters. The modal parameters are expected to contain environmental noise during experimentation, so, de-noising is must to obtain noise-free data. Artificial neural network training is utilized to reduce the noise from experimental modal parameters. Using the modified modal parameters, the mode shape curvature is obtained, and so-called modified mode shape curvature (MMSC) is used to calculate the curvature damage index. The curvature damage index is appropriate to investigate multiple fault locations with different fault levels in tubular rectangular beam structures. [ABSTRACT FROM AUTHOR]

Two sets of maleonitrile-tethered, N-atom-donor tridentate ligands which are configurationally isomeric, 2-((E)-(aryl-methylene)amino)-3-((pyridin-2-ylmethyl)amino)maleonitrile (HL1-Ar) and 2-((aryl-methyl)amino)-3-((E)-(pyridin-2-ylmethylene)amino)maleonitrile (HL2-Ar) have been synthesized and fully characterized (where the aryl groups are 4-methoxyphenyl (HL1-OMe/HL2-OMe), 4-(trifluoromethyl)phenyl (HL1-CF3/HL2-CF3) and 2,4,6-trimethylphenyl (HL1-Mes/HL2-Mes)). The competitive role of the ligand's electronic effect and the type of metal ion were explored on the reactivity of Co(II) and Ni(II) metal ions with differently electronically tuned ligands. An Ni(II) metal ion was found to be effective towards the irreversible transformation of HL1-Ar to HL2-Ar (for all substitutions on the aryl group) where the simultaneous oxidation of amine and reduction of imine take place within a single conjugated maleonitrile-tethered ligand. Whereas, Co(II) interacted differently with each member of HL1-Ar. With the presence of an electron-donating group (EDG), a methyl group (at ortho and para positions) in the phenyl ring of HL1-Mes, Co(II) could selectively perform the ligand transformation. On the other hand, HL1-CF3 and HL1-OMe (with the presence of less EDG in the phenyl ring in comparison to HL1-Mes) did not respond to the amine–imine interconversion process. The isolated Co(II) and Ni(II) complexes were fully characterized using crystallography, cyclic voltammetry, NMR and UV-Vis spectroscopy and the correlation of spectral data changes with the different electronic environments of the ligands was well explained. The redox instability of Co(II) complexes with HL2-Ar towards aerobic oxidation was studied using spectro-electrochemical analysis. Finally, a mechanism for the amine–imine interconversion process was proposed based on experimentally identified intermediates as well as DFT calculations. [ABSTRACT FROM AUTHOR]

Filamentous fungus Aspergillus niger has gained significant industrial and ecological value due to its great potential in enzymatic activities. The present study reports the complete genome sequence of A. niger BSC-1 which was isolated from Indian Sundarban mangrove ecosystem. The study revealed that the genome of A. niger BSC-1 was 35.1 Mbp assembled in 40 scaffolds with 49.2% GC content. A total of 10,709 genes were reported out of which 10,535 genes were predicted for encoding the proteins. BUSCO assessment showed 98.6% of genome completeness indicating high quality genome sequencing. The genome sequencing of A. niger BSC-1 revealed the presence of rodA and exgA genes for initial adhesion to surface and Ags genes for matrix formation, during biofilm growth. OrthoVenn2 analysis revealed that A.niger BSC-1 shared 9552 gene clusters with the reference strain A. niger CBS554.65. Semi-quantitative RT-PCR analysis unveiled the role of Ags1 and P-type ATPase in fungal biofilm formation and chromium (Cr) resistance, respectively. During biofilm growth the expression of Ags1 significantly (P < 0.0001; two-way ANOVA followed by Sidak's multiple comparisons test) increased with respect to planktonic culture revealing the possible involvement of Ags1 in biofilm matrix formation. Expression of P-type ATPase gene was significantly upregulated (P < 0.0001; one-way ANOVA followed by Dunnett's multiple comparisons test) with the increasing chromium concentration in the fungal culture. Besides, several other genes encoding metalloprotease, copper and zinc binding proteins, and NADH-dependent oxidoreductase were also found in the genome of A. niger BSC-1. These proteins are also involved in heavy metal tolerance and nanofabrication indicating that this filamentous fungus A. niger BSC-1 could be potentially utilized for chromium detoxification through biofilm or nanobiremediation. [ABSTRACT FROM AUTHOR]

Petroleum hydrocarbon contamination is a serious hazard to marine environments, affecting ecosystems and marine life. However, extracellular polymeric substances (EPS) of marine bacteria constituting various hydrophilic and hydrophobic functional groups sequester petroleum hydrocarbons (PHs). In this study, interaction of EPS of Pseudomonas furukawaii PPS-19 with PHs such as crude oil, n-dodecane, and pyrene and its impact on PHs adsorption was investigated. Protein component of EPS was increased after treatment with PHs. Red shift of UV–Vis spectra implied change in molecular structure of EPS. Functional groups of proteins (C O, NH 2) and polysaccharides (C–C, C–OH, C– O –C) predominantly interacted with PHs. Interaction with PHs affected secondary structure of EPS. Change in binding energies of corresponding functionalities of C 1s, O 1s, and N 1s confirmed the interaction. Disruption of crystalline peaks led to increased pore size in EPS primarily due to the increase in surface electronegativity. Static quenching mechanism unveils formation of complex between fulvic acid of EPS and PHs. Relative expression of alg8 gene was significantly increased in the presence of n-dodecane (6.31 fold) (P < 0.05; One way ANOVA). n-dodecane and pyrene adsorption capacity of Immobilized EPS was significantly higher (356.5 and 338.2 mg g−1, respectively) (P < 0.001; One way ANOVA) than control. Adsorption rate fits into the pseudo-second-order kinetic model. This study establishes that interaction of PHs causes structural and physical changes in EPS and EPS could be used as an adsorbent material for the sequestration of PHs pollution. [Display omitted] • Petroleum hydrocarbons (PHs) caused increased protein concentration in extracellular polymeric substances (EPS). • Interaction with PHs ensued in increased pore size, surface charge and mean particle size in EPS. • EPS interaction with PHs resulted in complexation following static quenching mechanism. • Alg8 gene showed enhanced expression in response to PHs. • EPS-alginate bioadsorbent showed high bioadsorption capacity as compared to calcium-alginate. [ABSTRACT FROM AUTHOR]

Cellulose degrading bacterial diversity of Bhitarkanika mangrove ecosystem, India, was uncovered and the cellulose degradation mechanism in Bacillus haynesii DS7010 under the modifiers such as pH (pCO 2), salinity and lead (Pb) was elucidated in the present study. The abundance of cellulose degrading heterotrophic bacteria was found to be higher in mangrove sediment than in water. The most potential strain, B. haynesii DS7010 showed the presence of endoglucanase, exoglucanase and β-glucosidase with the maximum degradation recorded at 48 h of incubation, with 1% substrate concentration at 41 °C incubation temperature. Two glycoside hydrolase genes, celA and celB were confirmed in this bacterium. 3D structure prediction of the translated CelA and CelB proteins showed maximum similarities with glycoside hydrolase 48 (GH48) and glycoside hydrolase 5 (GH5) respectively. Native PAGE followed by zymogram assay unveiled the presence of eight isoforms of cellulase ranged from 78 kDa to 245 kDa. Among the stressors, most adverse effect was observed under Pb stress at 1400 ppm concentration, followed by pH at pH 4. This was indicated by prolonged lag phase growth, higher reactive oxygen species (ROS) production, lower enzyme activity and downregulation of celA and celB gene expressions. Salinity augmented bacterial metabolism up to 3% NaCl concentration. Mangrove leaf litter degradation by B. haynesii DS7010 indicated a substantial reduction in cellulolytic potential of the bacterium in response to the synergistic effect of the stressors. Microcosm set up with the stressors exhibited 0.97% decrease in total carbon (C%) and 0.02% increase in total nitrogen (N%) after 35 d of degradation while under natural conditions, the reduction in C and the increase in N were 4.05% and 0.2%, respectively. The findings of the study suggest the cellulose degradation mechanism of a mangrove bacterium and its resilience to the future consequences of environmental pollution and climate change. [Display omitted] • GH48 and GH5 were confirmed within the cellulolytic system of B. haynesii DS7010. • Native PAGE with zymogram assay revealed the presence of eight cellulase isoforms. • Variable pH/pCO 2 and lead (Pb) negatively affected bacterial metabolism. • Salinity stress exhibited a positive effect on the bacterium up to 3% concentration. • Bacterial leaf litter degradation was severely affected by cumulative effect of stressors. [ABSTRACT FROM AUTHOR]

In the present work, the existence of multiple damage locations is identified successfully by using the modified mode shape curvature technique in a cantilever beam. The noisy frequency response of the beam is extracted for varying damage depths at two various positions by using Bruel and Kjaer instrument. As experimentally obtained displacement mode shape data cannot reflect clear damage location in the structure due to the presence of noise, in the present work, the data have been trained through artificial neural network to obtain improved results to localize the damage locations. Numerically and experimentally obtained displacement modes are utilized as input for ANN, and the trained data are used to produce mode shape curvature. The trained data sets are then utilized to produce the mode shapes curvatures for all the damage cases using central difference approximation. Damage severity and locations are then identified by analyzing the absolute mode shape curvature difference for various damage scenarios. [ABSTRACT FROM AUTHOR]

Biofilm forming and heavy metal resistant marine bacterial strain Pseudomonas chengduensis PPSS-4 was isolated from the contaminated marine sediment of Paradip Port, Odisha, India. The strain showed biofilm formation up to 100 mg/L of multi-metal [Pb(II), Cr(VI), and Cd(II)] supplementation in the culture medium. Scanning electron microscopy (SEM) showed aggregation of rod-shaped cells in the extracellular polymeric substance (EPS) matrix of biofilm. Confocal laser scanning microscopy (CLSM) exhibited a higher nucleic acid to the α-polysaccharide ratio in the biofilm, and the observed thickness was ~21 µm. The metal uptake potential of biofilm culture was higher than planktonic culture both in single and multi-metal solutions. FESEM-EDS analysis revealed the sequestration of multi-metals by bacterial cells and biofilm-EPS. FTIR analysis of bacterial EPS further ensured the interaction of functional groups such as –OH, –NH, and P=O with the metal ions. The maximum removal of Pb, Cr, and Cd by the bacterial biomass was observed at 37°C within 4 h of contact time at pH 6, and 4% salinity for Pb and Cr, and 6% salinity for Cd. The present study revealed that the marine bacterium P. chengduensis PPSS-4 can remove multi-metals, and this bacterium could be efficiently utilized for the remediation of heavy metals in the contaminated environment. [ABSTRACT FROM AUTHOR]

This article reported about the ultraviolet (UV) radiation effect on the resonance frequency response of a AT-cut piezoelectric quartz crystal. A large resonance frequency upshift was observed when the quartz crystal was irradiated by UV light of 355-nm wavelength using a Q-switched pulsed Nd:YVO4 UV laser. The dynamic frequency response behavior was systematically investigated by illuminating the quartz crystal with UV light in which the UV intensity was varied with time in staircase- and linear pulse-shaped patterns. From the experimental analysis, we measured the limit of detection and the sensitivity of the quartz crystal, which are about 0.5 mW/cm2 and 0.706 Hz/(mW/cm2), respectively. For a constant UV irradiation, a moderate response (<10 s) and recovery (<10 s) times were achieved during the on and off cycles of the UV light. The short-term repeatability and maximum operating limit of AT-cut quartz crystal were also further studied upon exposure to UV light with different intensities. In this work, we not only demonstrate the impact of UV irradiation on quartz crystal but also discuss the mechanism of upshift in resonance frequency upon exposure to UV light. This study shows the applicability of quartz crystal for the detection of UV light. [ABSTRACT FROM AUTHOR]

Rubber wastewater contains variable low pH with a high load of nutrients such as nitrogen, phosphorous, suspended solids, high biological oxygen demand (BOD), and chemical oxygen demand (COD). Ureolytic and biofilm-forming bacterial strains Bacillus sp. OS26, Bacillus cereus OS36, Lysinibacillus macroides ST13, and Burkholderia multivorans DF12 were isolated from rubber processing centres showed high urease activity. Microscopic analyses evaluated the structural organization of biofilm. Extracellular polymeric substances (EPS) matrix of the biofilm of the strains showed the higher abundance of polysaccharides and lipids which help in the attachment and absorption of nutrients. The functional groups of polysaccharides, proteins, and lipids present in EPS were revealed by ATR-FTIR and 1H NMR. A consortium composed of B. cereus OS36, L. macroides ST13, and B. multivorans DF12 showed the highest biofilm formation, and efficiently reduced 62% NH 3 , 72% total nitrogen, and 66% PO 4 3−. This consortium also reduced 76% BOD, 61% COD, and 68% TDS. After bioremediation, the pH of the remediated wastewater increased to 11.19. To reduce the alkalinity of discharged wastewater, CaCl 2 and urea were added for calcite reaction. The highest CaCO 3 precipitate was obtained at 24.6 mM of CaCl 2 , 2% urea, and 0.0852 mM of nickel (Ni2+) as a co-factor which reduced the pH to 7.4. The elemental composition of CaCO 3 precipitate was analyzed by SEM-EDX. XRD analysis of the bacterially-induced precipitate revealed a crystallinity index of 0.66. The resulting CaCO 3 precipitate was used as soil stabilizer. The precipitate filled the void spaces of the treated soil, reduced the permeability by 80 times, and increased the compression by 8.56 times than untreated soil. Thus, CaCO 3 precipitated by ureolytic and biofilm-forming bacterial consortium through ureolysis can be considered a promising approach for neutralization of rubber wastewater and soil stabilization. [Display omitted] • Biofilm-forming ureolytic bacterial consortia efficiently remediate rubber wastewater. • The pH of the wastewater was increased after bioremediation. • CaCl 2 and Ni2+ induced a high rate of calcium carbonate precipitation. • Calcium carbonate precipitate reduced the pH of the wastewater to a neutral level. • CaCO 3 precipitate treatment reduced permeability and increased compression of soil. [ABSTRACT FROM AUTHOR]

Bacteria thrive in biofilms embedding in the three-dimensional extracellular polymeric substances (EPS). Functional Amyloid in Pseudomonas (Fap), a protein in EPS, efficiently sequesters polycyclic aromatic hydrocarbons (PAHs). Present study reports the characterization of Fap fibrils from Pseudomonas aeruginosa PFL-P1 and describes the interaction with pyrene to assess the impact on pyrene degradation. Overexpression of fap in E. coli BL21(DE3) cells significantly enhances biofilm formation (p < 0.0001) and amyloid production (p = 0.0002), particularly with pyrene. Defibrillated Fap analysis reveals FapC monomers and increased fibrillation with pyrene. Circular Dichroism (CD), Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (XRD) unveil characteristic amyloid peaks and structural changes in Fap fibrils upon pyrene exposure. 3D-EEM analysis identifies a protein-like fluorophore in Fap fibrils, exhibiting pyrene-induced fluorescence quenching. Binding constants range from 5.23 to 7.78 M−1, with ΔG of −5.10 kJ mol−1 at 298 K, indicating spontaneous and exothermic interaction driven by hydrophobic forces. Exogenous Fap fibrils substantially increased the biofilm growth and pyrene degradation by P. aeruginosa PFL-P1 from 46 % to 64 % within 7 days (p = 0.0236). GC–MS identifies diverse metabolites, implying phthalic acid pathway in pyrene degradation. This study deepens insights into structural dynamics of Fap fibrils when exposed to pyrene, offering potential application in environmental bioremediation. [Display omitted] • Functional amyloid from P. aeruginosa PFL-P1 showed increased fibrillation with pyrene. • CD, FTIR, and XRD revealed amyloid peaks and pyrene-induced structural changes. • Fap fibrils spontaneously interact with pyrene through hydrophobic forces. • Pyrene binds to Fap fibrils at multiple sites with binding constants of 5.23–7.78 M−1. • Exogenous Fap fibrils enhanced biofilm-mediated pyrene degradation from 46 % to 64 %. [ABSTRACT FROM AUTHOR]

The adsorption behavior and interaction mechanisms of extracellular polymeric substances (EPS) of Pseudomonas aeruginosa OMCS-1 towards chromium (Cr), lead (Pb), and cadmium (Cd) were investigated. EPS-covered (EPS-C) cells exhibited significantly higher (p < 0.0001; two-way ANOVA) removal of Cr (85.58 ± 0.39%), Pb (81.98 ± 1.02%), and Cd (73.88 ± 1%) than EPS-removed (EPS-R) cells. Interactions between EPS-heavy metals were spontaneous (ΔG<0). EPS-Cr(VI) and EPS-Pb(II) binding were exothermic (ΔH<0), while EPS-Cd(II) binding was endothermic (ΔH>0) process. EPS bonded to Pb(II) via inner-sphere complexation by displacement of surrounding water molecules, while EPS-Cr(VI) and EPS-Cd(II) binding occurred through outer-sphere complexation via electrostatic interactions. Increased zeta potential of Cr (29.75%), Pb (41.46%), and Cd (46.83%) treated EPS and unchanged crystallinity (CI XRD =0.13), inferred EPS-metal binding via both electrostatic interactions and complexation mechanism. EPS-metal interaction was predominantly promoted through hydroxyl, amide, carboxyl, and phosphate groups. Metal adsorption deviated EPS protein secondary structures. Strong static quenching mechanism between tryptophan protein-like substances in EPS and heavy metals was evidenced. EPS sequestered heavy metals via complexation with C-O, C-OH, C O/O-C-O, and NH/NH 2 groups and ion exchange with –COOH group. This study unveils the fate of Cr, Pb, and Cd on EPS surface and provides insight into the interactions among EPS and metal ions for metal sequestration. [Display omitted] • The presence of EPS on bacterial surface facilitates the adsorption of metal ions. • EPS-metal binding was spontaneous, exothermic for Cr and Pb, and endothermic for Cd. • Electrostatic interaction and complexation mechanism of EPS and metal binding. • Heavy metal adsorption deviated the secondary structures of EPS proteins. • Static quenching mechanism between tryptophan containing proteins and heavy metals. [ABSTRACT FROM AUTHOR]

The marine bacterium Pseudomonas furukawaii PPS-19 isolated from the oil-polluted site of Paradip port, Odisha, India, was found to form a strong biofilm in 2% (v/v) crude oil. Confocal Laser Scanning Microscopy (CLSM) revealed biofilm components along with multi-layered dense biofilm of rod-shaped cells with 64.7 µm thickness. Scanning electron micrographs showed similar biofilm architecture covered with a gluey matrix of extracellular polymeric substances (EPS) in the presence of 2% (v/v) crude oil. The architecture of purified EPS was also studied through FESEM that exposed its porous and three-dimensional flakes-like structure. The structural characterization by FTIR revealed that EPS was composed of primary alkane, amines, halide, hydroxyl groups, uronic acid, and saccharides. The XRD profile exhibited an amorphous phase of the EPS with a crystallinity index of 0.336. The EPS showed three-step thermal decomposition and thermal stability up to 600 °C, as confirmed by TGA and DSC thermogram. EPS produced by marine bacterium P. furukawaii PPS-19 could act as bioemulsifier and showed the highest emulsifying activity of 66.23% on petrol. The emulsifying ability of the EPS was superior to the commercial polymer xanthan. The emulsion also showed high stability with time and temperature exposure. The marine bacterium P. furukawaii PPS-19 and the EPS complex showed 89.52% degradation of crude oil within 5 days. These properties demonstrated the potential of biofilm-forming marine bacterium as bioemulsifier for its application in the bioremediation of oil-polluted sites. [ABSTRACT FROM AUTHOR]

In this article, we report the synthesis techniques of ZnO nanoparticles (NPs) in open air atmosphere by pulse laser ablation (PLA) method using solid ZnO polycrystalline palette followed by fabrication of formaldehyde (HCHO) sensor. The crystalline phase and morphology of the obtained ZnO NPs were studied by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM), respectively. The XRD patterns showed that the NPs were polycrystalline structure with good crystallinity. The FESEM images revealed that the NPs were spherical in shape and loosely agglomerated. The average diameter of the NPs was in the range of 30–43 nm. Moreover, the ZnO NPs-based sensor exhibited excellent formaldehyde sensing performance at a temperature of 350 °C. The sensor exhibited a gas response of about 5.2 toward 300 ppm formaldehyde with 25 s response and 12 s recovery time. Furthermore, the ZnO NPs-based sensor exhibited excellent reliability and reproducibility to formaldehyde. On the other hand, the sensor showed high sensitivity of about 0.2% ppm −1 to formaldehyde with a 50 ppm lower detection limit. In addition, the sensor showed an excellent linear relationship (R2 = 0.7948) between the response and the concentration of formaldehyde in the range of 50–400 ppm. This work demonstrates that PLA in open air is a rapid and cost-effective method for synthesizing metal oxide NPs for gas-sensing applications without the need for wet chemical routes. [ABSTRACT FROM AUTHOR]

Here, an ultrafast direct laser patterning technique to fabricate a low-cost microsensor and its application for formaldehyde detection are reported. The patterns of microheater and interdigitated electrodes (IDEs) were realized using laser micromachining techniques by ablation of gold thin film on alumina substrate. The thin film of gold microheater showed good stability up to 300 °C with a fast response time of 80 s and temperature coefficient of resistance (TCR) was calculated as 1.37 × 10−3/°C. Moreover, gold microheater exhibited long-term reliability under self-heating mode with a negligible resistance drift < 0.5% over a period of 330 h at 250 °C through consuming low power with a heating efficiency of 0.23 °C/mW. Thermal imaging camera revealed the uniform temperature distribution with negligible heat gradient profile over the whole microsensor platform. To state-of-the-art gas sensing application of this coplanar sensing platform, a nanostructured SnO2 was deposited on IDE, which exhibited high sensitivity (13.96% ppm−1) to formaldehyde even to detect sub-ppm concentrations with fast response (32 s) and recovery kinetics (72 s). Moreover, the microsensor was also used on-site rapid screening for the detection and quantification of formaldehyde concentration in formalin-treated fish sample. [ABSTRACT FROM AUTHOR]

Estimation of post-mortem time interval (PMI) is a key parameter in the forensic investigation which poses a huge challenge to the medico-legal experts. The succession of microbes within different parts of the human body after death has shown huge potential in the determination of PMI. Human body harbors trillions of microorganisms as commensals. With the death of an individual when biological functions are stopped, these microorganisms behave contrarily along with the invasion of degrading microbes from the environment. Human cadaver becomes a rich source of nutrients due to autolysis of cells, which attracts various invading microorganisms as well as macroorganisms. At different stages of degradation, the succession of microorganisms differs significantly which can be explored for accurate PMI estimation. With the advent of microbial genomics technique and reduction in the cost of DNA sequencing, thanatomicrobiome and epinecrotic community analysis have gained huge attention in PMI estimation. The article summarizes different sources of microorganisms in a human cadaver, their succession pattern, and analytical techniques for application in the field of microbial forensics. Key points: • Thanatomicrobiome and epinecrotic microbiome develop in postmortem human body. • Lack of metabolic, immune, neuroendocrine systems facilitate microbial succession. • Analysis of postmortem microbial communities predicts accurate PMI. [ABSTRACT FROM AUTHOR]

Introduction: Malaria is devastating infectious disease not only India but also throughout the globe due to its high morbidity and mortality factor for last few centuries. From 19th and early 20th centuries, almost a quarter of the Indian populations were severely suffering from malaria. The economic loss due to increased mortality in malaria was estimated 10 million rupees per year in 1935. According to the World Malaria Report of 2017, malaria incidence accounted for 58% of cases in India. The objective of this study is to prediction of "annual" malaria incidences in India, depending on the basis of last 22 years national malaria epidemiology data. Methods: This study uses data from the official website of the National Program for the Control of Vector borne Diseases (NVBDCP) (http://nvbdcp. gov.in/) from 1995 to 2016. For creating a forecasting tool on Malaria surveillance in India, Econometric forecasting model (ARIMA Model ((0,1,1) (1,0,0) 12)) was used. Results: ARIMA statistical model ((0,1,1) (1,0,0) 12) found to be highly effective and significant (P < 0.05) in prediction of future epidemiological surveillance of malaria in India. ARIMA statistical model could be successfully use in prediction of annual malaria incidences in India after adjusting different highly contributing environmental and geographical factors, such as climate change, temperature, rainfall, and relative humidity. Conclusion: The historical forecast of the occurrence of malaria in India will allow the government to improve planning, control and prevention through public health interventions. In addition, the pharmaceutical industry will assist medical members in pre-treatment and drug interventions to respond to the increased or decreased occurrence of malaria. [ABSTRACT FROM AUTHOR]

Background: Acute Pancreatitis is a common disease with wide clinical variation and its incidence is increasing. Acute pancreatitis is an inflammatory process leading to abdominal pain, progressive destruction of exocrine tissue and in some patients a loss of endocrine tissue as well, with multiple organ failure and high mortality. Severity of acute pancreatitis is linked to the presence of systemic organ dysfunction and/or necrotizing pancreatitis. Aims and Objective: The present study was aimed to study the clinical profile of acute pancreatitis, the etiology and complications of acute pancreatitis received treatment in the Department of Surgery, Tripura Medical College & Dr. BRAM Teaching Hospital, Agartala, Tripura. Materials and Methods: This was a hospital based retrospective study which was conducted from January 2019 to December 2019. All patients with a diagnosis of acute pancreatitis were included in this study in order to find out the clinical presentations from the available clinical, laboratory and radiological data. Results: Of the 100 patients in this study, 96 were male and 4 were female. Minimum age in our study was 10 years and maximum were 70 years. Maximum numbers of patients were below 45 years of age. Alcohol was identified as the most important etiological factor associated with acute pancreatitis. Among the known etiological factors 90% of the cases were related to alcoholism and 4% were due to gall stone disease. Abdominal pain and vomiting were the most common symptoms in our study. Epigastric tenderness was present in 90% of the cases and guarding/rigidity in 50% of cases. 14% patients showed jaundice as a sign of acute pancreatitis. There was no major difference between the CT grading system and clinical grading system. Most of the patients recovered with conservative treatment. Adverse outcome was noted in one patient with acute necrotizing pancreatitis. Conclusion: Acute pancreatitis is one of the leading causes of increase in morbidity and mortality to society. Clinical assessment along with radiological findings correlated well with the morbidity and mortality. Our study identifies alcoholism as one of the most important etiological factors. [ABSTRACT FROM AUTHOR]

Mangifera indica is a tree found in nature from ancient time and full of benefits to health and disease preventive strategies. It bears the botanical name as - Mangifera indica L. It has a lot of medicinal and nutritional importance as well as used in auspicious rituals. Having multiple health benefits M. indica has been proven a natural alternative medicine to many of life threatening disorders. Various research studies on M. indica have been reported remedial effect against different ailments including diabetes mellitus, certain bacterial diseases and oxidative stress induced disorders. In this context, the main aim of this review is to present various pharmacological activities of M. indica. From literature survey finally it is concluded that M. indica in its various forms are beneficial in multiple health aspects without having any adverse side effects. So it can be an effective way to minimize the complications of certain disorders as well as promotion of health. [ABSTRACT FROM AUTHOR]

Ferulic acid is a potent anti-oxidant with scientifically proven skin care efficacies. However, instability of this active in the skin care products restricted its wide application in beauty and skin care industries. This study aimed to stabilize ferulic acid in topical hydrogel formulation via nanoencapsulation technique. Ferulic acid loaded nanocapsules were prepared via high pressure homogenization method and physicochemically characterized. Mean particle size of ferulic acid loaded nanocapsules was < 300 nm. TEM and SEM images exhibited spherical particles with smooth surface. DSC and XRD results indicated that ferulic acid was completely dissolved in the lipid matrix of the nanocapsules and remained in amorphous form. Two types of hydrogel formulations containing ferulic acid loaded nanocapsules were prepared: Gel A with pH higher and Gel B with pH lower than pKa of ferulic acid. Cross-polarized microscopic image of the gel formulations did not show presence of any un-encapsulated and un-dissolved crystal. Gel B showed slower and controlled release of ferulic acid than Gel A. Ferulic acid permeation through skin mimic from the gel formulation demonstrated controlled permeation. Color stability of the gel and chemical stability of ferulic acid were very good in Gel B, while poor in Gel A (although significantly better than the gel with un-encapsulated ferulic acid). The result clearly indicates that together with nanoencapsulation, low pH (less than pKa of ferulic acid) of the hydrogel was crucial for both product appearance and chemical stability of ferulic acid. In fact, it has been proved that skin care product with low pH is good for skin as it can maintain skin homeostasis and microbiome. Furthermore, the permeation result suggests that ferulic acid may penetrate into deep skin layers and at the same time avoid systemic circulation. Overall, this low pH hydrogel formulation containing nanoencapsulated ferulic acid demonstrates great promise for commercialization. [ABSTRACT FROM AUTHOR]

A new N- and S-rich highly ordered periodic mesoporous organosilica material DMTZ-PMO bearing thiadiazole and thiol moieties inside the pore-wall of a 2D-hexagonal nanomaterial has been synthesized. DMTZ-PMO shows a very high surface area (971 m2 g−1), and can be used for efficient and fast removal of Hg2+ from polluted water with a very high Hg2+ uptake capacity of 2081 mg g−1. [ABSTRACT FROM AUTHOR]

Renaissance of cocrystals as alternative solid forms for fine-tuning physicochemical properties of active pharmaceutical ingredients (APIs) has paved way for development of marketable cocrystals. The current literature reveals established strategies for the design, synthesis and characterization of cocrystals. However, barring a few isolated case studies, strategies for development of cocrystal formulations have been underdeveloped. Herein we report topical formulations of an antioxidant, ferulic acid (FA), which contain the active in its cocrystal form. Cocrystals of FA with the coformers relevant to skin care such as urea, nicotinamide (NA) and isonicotinamide (INA) have been prepared and oleogel formulations of these have been developed. The cocrystal with urea and an anhydrous cocrystal with INA have been identified for the first time in this study. The novel cocrystals were structurally characterized by single crystal X-ray diffraction. Solubility and stability studies have revealed higher solubility of the cocrystals with NA and INA than the parent active and greater stability of FA in formulations that contained the cocrystals with INA and urea than the corresponding formulations containing physical mixtures or parent active. In vitro membrane permeation tests have ascertained sustained release profile of active from the formulation that contained the FA•INA cocrystal. The higher solubility, greater stability and sustained active release profile of the FA•INA cocrystal formulation make it a promising topical formulation of FA. [ABSTRACT FROM AUTHOR]

Antimicrobial peptides (AMPs), found in both animals and plants, are used to fend off a wide variety of invading pathogens, such as bacteria, fungi, protozoa, viruses, etc. Their widespread distribution and defensive activity towards all different microbes lead to the successful evolution of complex multicellular organisms. In particular, AMPs target bacterial membranes and disrupt the membrane via the formation of transmembrane pores without interacting with any specific receptors. It is known that different antimicrobial peptides use different mechanisms to disrupt the membrane by forming transmembrane pores. The interaction of the antimicrobial peptide with the membrane depends on peptide charge, hydrophobicity, membrane composition, etc. Therefore, to get insights into the mechanisms of membrane disruption, it is useful to study the model membrane, as biological membranes are complex and regulated by various other proteins, cholesterol, etc. In the present review, we will primarily describe the interaction of antimicrobial peptides with phospholipid membranes, which mimic the bacterial membrane, in view of understanding the mechanism of action, various factors affecting their activity, application prospects in drug therapeutics, etc. [ABSTRACT FROM AUTHOR]

We have conducted experiments with the Community Atmospheric Model version 5.1 configured as an aquaplanet, with the sun at March equinox, in order to study how the model Madden-Julian oscillation (MJO) responds to (i) the introduction of continents and (ii) realistic sea surface temperature (SST) distribution. Model results are compared with ERA-Interim reanalysis and analyzed in terms of the moist static energy (MSE) budget to study the growth and propagation of MJO. With idealized zonally symmetric SST, the aquaplanet model produces a double Intertropical Convergence Zone (ITCZ) and an MJO-like mode with variance at intraseasonal (30- to 96-day) periods and zonal wave number 1. When we introduce continents with realistic orography and interactive surface temperature, soil moisture, and albedo, the variance of MJO is mainly confined to zonal wave numbers 1 and 2 but reduced by a factor of 3 due to weaker boundary layer moisture convergence. With prescribed climatological January SST boundary condition (which includes Indo-west Pacific warm pool) in the presence of continents, model MJO variance is enhanced and distributed across zonal wave numbers 1 to 5, in closer agreement with observation. Thus, the presence of land by itself is not enough, but realistic SST distribution is necessary for improved space-time characteristics of model MJO. Both in simulations and ERA-Interim data, meridional and vertical advection of MSE promotes eastward movement of MJO. In the model experiments, meridional advection of low-level MSE anomaly is most significant in the vicinity of the ITCZ, indicating the importance of processes that determine the location of (single or double) ITCZ. [ABSTRACT FROM AUTHOR]

Biofilm-forming marine bacterium Pseudomonas furukawaii PPS-19 showed strong hydrophobicity under different physicochemical stressors, such as pH and salinity. Strong aggregation of P. furukawaii PPS-19 was observed at hydrophobic interfaces of n-dodecane and crude oil, while uptake of pyrene resulted in blue fluorescence of the bacterium. Changes in biofilm microcolonies were observed under different physicochemical stressors with maximum biofilm thickness of 15.15 µm and 15.77 µm at pH 7% and 1% salinity, respectively. Relative expression analysis of alkB2 gene revealed the maximum expression in n-dodecane (10.5 fold) at pH 7 (1 fold) and 1% salinity (8.3 fold). During the degradation process, a significant drop in surface tension resulted in increased emulsification activity. P. furukawaii PPS-19 showed the respective n-dodecane and pyrene degradation of 94.3% and 81.5% at pH 7% and 94.5% and 83% at 1% salinity. A significant positive correlation was obtained between cell surface hydrophobicity (CSH), biofilm formation, and PHs degradation (P < 0.05) under all the physicochemical stressors, with the highest value at pH 7% and 1% salinity. Analysis of metabolites indicated that mono-terminal oxidation and multiple pathways were followed for n-dodecane and pyrene biodegradation, respectively. Thus, P. furukawaii PPS-19 is an efficient hydrocarbonoclastic bacterium that may be exploited for large-scale oil pollution abatement. [Display omitted] • Biofilm-forming Pseudomonas furukawaii PPS-19 showed high cell surface hydrophobicity. • cell surface hydrophobicity positively influenced biofilm and degradation. • alkB 2 gene showed expression in response to various physicochemical stressors. • P. furukawaii PPS-19 followed mono-terminal oxidation pathways for the degradation. [ABSTRACT FROM AUTHOR]

Increasing usage of plastic has led to the deposition of plastic in the environment which later become microplastic, a pollutant of global concern. These polymeric particles affect the ecosystem by increasing ecotoxicity and impeding the biogeochemical cycles. Besides, microplastic particles have been known for their role in aggravating the effect of various other environmental pollutants including organic pollutants and heavy metals. These microplastic surfaces are often colonized by the microbial communities also known as "plastisphere microbes" forming biofilms. These microbes include cyanobacteria like Nostoc , Scytonema , etc., and diatoms like Navicula , Cyclotella , etc. which become the primary colonizer. In addition to the autotrophic microbes, Gammaproteobacteria and Alphaproteobacteria dominate the plastisphere microbial community. These biofilm-forming microbes can efficiently degrade the microplastic in the environment by secreting various catabolic enzymes such as lipase, esterase, hydroxylase, etc. Besides, these microbes have shown great potential for the bioconversion of microplastic to polyhydroxyalkanoates (PHA), an energy efficient and sustainable alternative to the petroleum based plastics. Thus, these microbes can be used for the creation of a circular economy using waste to wealth strategy. This review provides a deeper insight into the distribution, transportation, transformation, and biodegradation of microplastic in the ecosystem. The formation of plastisphere by the biofilm-forming microbes has been described in the article. In addition, the microbial metabolic pathways and genetic regulations involved in the biodegradation have been discussed in detail. The article suggests the microbial bioremediation and upcycling of microplastic along with various other strategies to effectively mitigate the microplastic pollution. [Display omitted] • Microplastics are ubiquitous environmental pollutants. • Microplastic surfaces are colonized by biofilm-forming plastisphere microbes. • Plastisphere microbes can efficiently degrade the microplastic in the environment. • The genetic regulation and metabolism help the microbes in biodegradation. • Various microbes have the potential for the bioconversion of microplastic to PHA. [ABSTRACT FROM AUTHOR]

Increasing industrialization and anthropogenic activities have resulted in the release of a wide variety of pollutants into the environment including pesticides, polycyclic aromatic hydrocarbons (PAHs), and heavy metals. These pollutants pose a serious threat to human health as well as to the ecosystem. Thus, the removal of these compounds from the environment is highly important. Mitigation of the environmental pollution caused by these pollutants via bioremediation has become a promising approach nowadays. Actinobacteria are a group of eubacteria mostly known for their ability to produce secondary metabolites. The morphological features such as spore formation, filamentous growth, higher surface area to volume ratio, and cellular mechanisms like EPS secretion, and siderophore production in Actinobacteria render higher resistance and biodegradation ability. In addition, these bacteria possess several oxidoreductase systems (oxyR , catR , furA , etc.) which help in bioremediation. Actinobacteria genera including Arthrobacter , Rhodococcus , Streptomyces , Nocardia , Microbacterium , etc. have shown great potential for the bioremediation of various pollutants. In this review, the bioremediation ability of these bacteria has been discussed in detail. The utilization of various genera of Actinobacteria for the biodegradation of organic pollutants, including pesticides and PAHs, and inorganic pollutants like heavy metals has been described. In addition, the cellular mechanisms in these microbes which help to withstand oxidative stress have been discussed. Finally, this review explores the Actinobacteria mediated strategies and recent technologies such as the utilization of mixed cultures, cell immobilization, plant-microbe interaction, utilization of biosurfactants and nanoparticles, etc., to enhance the bioremediation of various environmental pollutants. [Display omitted] • Actinobacteria are industrially important bacteria with huge metabolic potential. • Actinobacteria can bioremediate various organic and inorganic pollutants. • Cellular mechanisms and metabolic pathways in Actinobacteria aid in bioremediation. • Genetic regulation in Actinobacteria provide tolerance towards the oxidative stress. • Adoption of efficient strategies can enhance the bioremediation by Actinobacteria. [ABSTRACT FROM AUTHOR]

In this study, we have reported the fabrication of p-NiO/n-SnO 2 heterojunction based formaldehyde (HCHO) sensor by decorating the surface of pre-deposited SnO 2 thin film with laser ablated NiO nanoparticles (NPs). In atmospheric air, NiO NPs were produced by a moving laser beam on the surface of pure (99.99%) Ni pellet to decorate sputtered deposited SnO 2 thin film directly to form NiO/SnO 2 p-n heterojunction. After fabrication, gas sensing properties of NiO/SnO 2 sensor were investigated systemically towards HCHO and it exhibited higher response (R a /R g) of about 31.04 towards 50 ppm HCHO at 210 °C with good selectivity compared with pristine SnO 2 sensor. Moreover, adsorption (K a) and desorption rate constant (K d), response time (τ res), recovery time (τ rec) and surface coverage (θ) of NiO/SnO 2 sensor were extracted from experimental data using Langmuir gas adsorption-desorption model via curve fitting method and the models demonstrated the irreversible type of gas sensing behaviour towards HCHO. The experimental results revealed that the laser ablation method has a great potential to use as alternative chemical free surface decoration route to fabricate metal oxide heterojunction based sensors for the detection of formaldehyde or other toxic gases. [Display omitted] • The NiO nanoparticles were synthesized in air by laser ablation technique. • The p-NiO/n-SnO 2 heterojunction has been formed by direct deposition of NiO nanoparticles on SnO 2 thin-film. • The NiO/SnO 2 sensor shows fast and high response to formaldehyde at 210 °C with good selectivity. • Langmuir adsorption-desorption model and curve fitting were used to extract gas sensing parameters. [ABSTRACT FROM AUTHOR]

Introduction: The use of radiology, especially ultrasonography, is widely prevalent in obstetric care worldwide. Ultrasonography studies during pregnancy are used to identify fetal abnormalities that may impact the health of the fetus as well as that of the child post-delivery. Aims: To determine the normal values of fetal Myocardial Performance Index (MPI) and lay down its importance in the cardiac workup of foetuses. Materials and Methods: This is a Hospital based observational Prospective Study. It's conducted from 1st April 2021 to 30th September, 2022 at Department of Radio-diagnosis in collaboration with Department of Obstetrics & Gynecology, Burdwan Medical College and Hospital. 115 patients were include in this study. Result: Among 115 mothers, 53.9% were primi-gravida, 33.9% were 2nd gravida and rest 12.2% were 3rd gravida, 57.4% undergo Normal vaginal delivery, 17.4% undergo vaginal delivery with induction and 25.2% undergo caesarean section and among 115 babies 82.6% had normal birth weight rest 17.4% were low birth weight babies. Conclusion: We conclude that myocardial performance index is a better predictor of adverse perinatal outcome than an abnormal IVCT or IVRT. Best results are obtained when MPI is used, rather than IVCT, IVRT and ET separately. In our study MPI had the highest sensitivity of 88.8% in predicting adverse fetal outcomes and 92.3% in predicting perinatal mortality. If the MPI ratio is normal, the fetus is unlikely to have major adverse outcome. This information would be reassuring to parents and referring obstetricians and in addition the fetus would not require intensive surveillance. Doppler patterns follow a longitudinal trend with early changes in the E/A ratio with advancing gestational ages. Fetal heart rate shows a declining trend with increasing gestational age. There was no statistically significant correlation between gestational age with MPI, ICT, IRT and ET. [ABSTRACT FROM AUTHOR]

Applications of probiotic bacteria and nanoparticles (NPs) as therapeutic agents have great importance. This study demonstrates a combinatorial approach of both the probiotic Lactobacillus spp. ( Lactobacillus fermentum and Lactobacillus plantarum) with fluorescent cadmium sulfide (CdS) NPs as therapeutic agents to target MCF-7 cancer cells (human breast cancer cells). In this study, facultative anaerobic Lactobacillus was successfully used as a vehicle to transport NPs into MCF-7 cancer cells. The cell viability assay and invasion study along with confocal and field emission scanning electron microscopy (FESEM) confirmed the release of payload (CdS NPs) into cytoplasm without any external stimuli. The biosynthesized CdS NPs of ∼22 nm were characterized by FESEM, transmission electron microscopy (TEM), atomic force microscopy (AFM), and fluorescence spectroscopy. The bacteria-NPs (microbots) interaction was investigated by growth curve studies, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), FESEM, energy dispersive X-ray spectroscopy (EDX), and fluorescence and confocal microscopy. This alternative approach showed an approved and inexpensive delivering mode of specific functional cargos or therapeutic agents into the cancer cells. [ABSTRACT FROM AUTHOR]

Microbes are the most fascinating group, with huge diversity devising myriad functional applications in the field of medicine, pharmaceuticals, environmental remediation, and industries. Quantitative and qualitative determination of biomolecules and microbial assisted phenomena by spectroscopy is a pioneer approach. It facilitates the study of atomic and molecular geometries, energy levels, chemical bonds, and interactions between molecules and microbes. It produces fingerprints of the microbial species serving to characterize, differentiate, and identify microorganisms, in both the environment and at single-cell level. Spectroscopy-based bioremediation techniques like Fourier transform infrared spectroscopy, mass spectroscopy, force spectroscopy, Raman spectroscopy, photoemission spectroscopy, and laser-induced breakdown spectroscopy have been very well represented and linked with the microbial applications. This review summarizes the traditional spectroscopic techniques used for the study of microbes and microbial-assisted products as well as illustrates its application in the field of microbial diversity and remediation. This will provide an outlook for the intricate characterization and dimension of microbes to be used for effective application in bioremediation. [ABSTRACT FROM PUBLISHER]

Metal pollution is one of the most persistent and complex environmental issues, causing threat to the ecosystem and human health. On exposure to several toxic metals such as arsenic, cadmium, chromium, copper, lead, and mercury, several bacteria has evolved with many metal-resistant genes as a means of their adaptation. These genes can be further exploited for bioremediation of the metal-contaminated environments. Many operon-clustered metal-resistant genes such as cadB, chrA, copAB, pbrA, merA, and NiCoT have been reported in bacterial systems for cadmium, chromium, copper, lead, mercury, and nickel resistance and detoxification, respectively. The field of environmental bioremediation has been ameliorated by exploiting diverse bacterial detoxification genes. Genetic engineering integrated with bioremediation assists in manipulation of bacterial genome which can enhance toxic metal detoxification that is not usually performed by normal bacteria. These techniques include genetic engineering with single genes or operons, pathway construction, and alternations of the sequences of existing genes. However, numerous facets of bacterial novel metal-resistant genes are yet to be explored for application in microbial bioremediation practices. This review describes the role of bacteria and their adaptive mechanisms for toxic metal detoxification and restoration of contaminated sites. [ABSTRACT FROM AUTHOR]

Metabolic pathway of biphenyl assimilation and the catabolic gene expression in a marine bacterium Pseudomonas aeruginosa JP-11, isolated from the coastal sediments of Odisha, India have been studied. This strain utilized 98.86% ± 2.29% of biphenyl within 72 h when supplied as the sole source of carbon, however, preferential utilization of glucose was observed over catechol and biphenyl when grown in a complex medium. Combination of chromatographic and spectrophotometric techniques confirmed the catechol pathway and identified 2-Hydroxy-6-oxo-6-phenylhexa-2, 4-dienoate as the intermediate metabolic product. Assimilation of biphenyl was initiated by its dioxygenation, forming cis-2, 3-dihydro-2, 3-dihydroxybiphenyl subsequently transformed to 2-hydroxy-6-oxo-6-phenylhexa-2, 4-dienoate. In the lower pathway, cis-1, 6-dihydroxy-2, 4-cyclohexadiene-1-carboxylic acid was detected which formed catechol before entering into the Krebs cycle. Detection of key enzyme catechol-1, 2-dioxygenase in the cell-free extract of P. aeruginosa JP-11 supported the proposed degradation pathway. The primary enzyme for biphenyl assimilation, biphenyl dioxygenase encoded by bphA gene was found in the genome of the isolate. On increasing biphenyl stress (50, 100, 150 and 200 mg L −1 ), bphA gene showed a significant (P < 0.01) up-regulation upto 43.5 folds. Production of biosurfactant was confirmed and the rhamnolipid synthesizing gene rhlAB was amplified. This gene also showed a significant (P < 0.01) up-regulation upto 258 folds on increasing biphenyl stress. [ABSTRACT FROM AUTHOR]

Heterojunction based metal oxide semiconductors have a great potential to detect toxic gases and volatile organic compounds. Here, we report a synthesis technique to obtain ZnO nanoparticles (NPs) via laser ablation method in ambient atmosphere using a nanosecond pulse laser. The laser ablated ZnO NPs were used for the decoration of sputtered deposited SnO 2 thin film to realize n-type ZnO/n-type SnO 2 heterojunction based formaldehyde (HCHO) gas sensor. Fabricated ZnO/SnO 2 sensor shows 3 times higher response (response = 20) to 50 ppm HCHO, faster response-recovery dynamics (τ res = 4 s and τ rec = 30 s) and better selectivity compared to pristine SnO 2 sensor at lower operating temperature (250 °C). The ZnO/SnO 2 heterojunction based sensor also can detect < 0.25 ppm HCHO, which allows for lower detectable limit of sub-ppm HCHO. Therefore, the ZnO/SnO 2 sensor shows enhanced sensing performance due to oxygen vacancies and n-n heterojunction structures provides more effective electrons for oxygen adsorption which speeds up the electronic transport at the interface of two materials. Synthesis of metal oxide composite NPs using pulse laser ablation method could be a promising alternative rapid route for the fabrication of highly sensitive gas sensors to detect most common indoor air pollutant. • Fabrication of highly selective and ultrasensitive n-SnO 2 /n-ZnO heterojunction-based formaldehyde gas sensor. • ZnO nanoparticles were synthesized using rapid and cost-effective laser ablation techniques in air. • The sensor exhibits high gas sensing response at 200 °C with ultra-low detection limit of 0.25 ppm. • SnO 2 /ZnO sensor shows better sensitivity and selectivity of as compared to pristine SnO 2. [ABSTRACT FROM AUTHOR]

Bacterial biofilm formation is dependent mainly on the decision-making process of the two key factors of the gene regulatory network, namely the Quorum Sensing (QS) system and bis-(3′-5′)-cyclic dimeric guanosine monophosphate (c-di-GMP). c-di-GMP is a secondary messenger molecule that enhances extracellular polysaccharides production by activating pelD and alg44. Genes involved in the metabolic pathway for the biosynthesis of extracellular polysaccharides are clustered within the genome of the producing bacteria. The extracellular polysaccharide gene cluster encodes specific regulatory enzymes and transporter proteins involved in the different steps of the biosynthesis route. The diversity of extracellular polysaccharides produced by the bacteria is synthesized via different biosynthesis pathways. Understanding the genetic regulation and biosynthesis of extracellular polysaccharides is crucial for tailor-made polymers via genetic, metabolic, and protein engineering approaches. This review illustrates structure, structure-function relationship, genetics, regulation, biosynthetic pathways, and various applications of extracellular polysaccharides. [Display omitted] [ABSTRACT FROM AUTHOR]

A transgenic bacterium Bacillus cereus BW-03( p PW-05) was constructed by transforming a plasmid harbouring mer operon of a marine bacterium Bacillus thuringiensis PW-05 into another mercury resistant marine bacterium B. cereus BW-03 with mercury biosorption capability. The transformant was able to remove >99% of mercury supplement in-vitro by simultaneous volatilization (>53%) and biosorption (∼40%). Encapsulation of the transformant increased its mercury removal potential to almost 100%. Additionally, B. cereus BW-03( p PW-05) could resist wide variations of salinity (5–30 ppt), pH (Brierley et al., 1989; Chung et al., 1989; Chen and Wilson, 1997; Chakraborty and Das, 2014) and mercury (5–50 ppm) and survived in mercury contaminated simulated environment up to 7 days. –SH and –COOH groups were possibly involved for mercury biosorption under laboratory conditions. The potential for application of this transgenic bacterium for in-situ bioremediation was demonstrated in a microcosm experiment, where it removed 96.4% inorganic mercury synergistically with the normal microbiota. [ABSTRACT FROM AUTHOR]

A comparative response of marine bacteria Pseudomonas pseudoalcaligenes NP103 and P. aeruginosa N6P6 under pH stress and UV radiation (UVR) revealed that both their survival pattern and repair mechanism are species specific. In case of P. pseudoalcaligenes NP103, the survival was maximum at pH 8, which decreased with decline in pH of the medium. Whereas, in P. aeruginosa N6P6, maximum survival was observed at pH 7. On exposure to UVR at different doses (25-200 mJ/cm) and increasing concentrations of Na (1-6%), considerable differences in the recovery (2% for P. pseudoalcaligenes NP103 and 3% for P. aeruginosa N6P6) from UVR induced damage was observed. The qRT-PCR analysis of DNA repair genes ( recA and uvrA) of marine bacteria subjected to different pH conditions showed significant ( P < 0.05) up-regulation of both genes at pH 6, indicating higher degree of DNA damage at low pH. Furthermore, exposure of UVR irradiated cell suspensions to visible light exhibited greater photo-reactivating capacity in P. pseudoalcaligenes NP103 as compared to P. aeruginosa N6P6. The present findings indicate that pH and UVR exposure have crucial role in dictating the light dependent and independent DNA repair pathway in marine bacteria. Further, we speculate that both these repair response to the environmental stressors varies with bacterial species. [ABSTRACT FROM AUTHOR]

Increasing level of polycyclic aromatic hydrocarbons (PAHs) in the environment results in environmental pollution. Microbial biofilm-mediated bioremediation has been widely used as an attractive approach to mitigate PAHs contamination in the ecosystem. Amyloid, a proteinaceous component of biofilm-associated extracellular polymeric substances (EPS), forms an integral strengthening part of the biofilm. This study aims to determine the interaction of functional amyloid in Pseudomonas (Fap) with two different PAHs (phenanthrene and pyrene). The production of amyloid by the marine bacterium Pseudomonas aeruginosa PFL-P1 was confirmed by Congo red (CR) assay, thioflavin T (ThT) staining method and amplification of fapC gene. The expression of fapC was up-regulated six folds (p < 0.0001) when phenanthrene and pyrene were used as the sole carbon source. The molecular docking of modelled FapC revealed a strong binding energy of − 7.0 and − 6.75 kcal/mol with phenanthrene and pyrene, respectively. Confocal laser scanning microscopic (CLSM) analysis indicated a significant increase in amyloid percentage during biofilm formation by P. aeruginosa PFL-P1 in the presence of phenanthrene and pyrene (p < 0.0001). The increased expression of the fapC gene and the potent hydrophobic interaction between the FapC protein and the PAH molecules suggest the essential role of this protein in PAH binding. [Display omitted] • Marine bacterium Pseudomonas aeruginosa PFL-P1 showed amyloid-producing ability. • Amyloid production increased under polycyclic aromatic hydrocarbon stress. • fapC encodes the major amyloid protein in Pseudomonas. • In silico study revealed β-sheet-rich region in the tertiary structure of FapC. • FapC was found to interact hydrophobically with polycyclic aromatic hydrocarbon. [ABSTRACT FROM AUTHOR]

The major proportion of earth's biological diversity is inhabited by microorganisms and they play a useful role in diversified environments. However, taxonomy of microorganisms is progressing at a snail's pace, thus less than 1% of the microbial population has been identified so far. The major problem associated with this is due to a lack of uniform, reliable, advanced, and common to all practices for microbial identification and systematic studies. However, recent advances have developed many useful techniques taking into account the house-keeping genes as well as targeting other gene catalogues (16S rRNA, rpoA, rpoB, gyrA, gyrB etc. in case of bacteria and 26S, 28S, β-tubulin gene in case of fungi). Some uncultivable approaches using much advanced techniques like flow cytometry and gel based techniques have also been used to decipher microbial diversity. However, all these techniques have their corresponding pros and cons. In this regard, a polyphasic taxonomic approach is advantageous because it exploits simultaneously both conventional as well as molecular identification techniques. In this review, certain aspects of the merits and limitations of different methods for molecular identification and systematics of microorganisms have been discussed. The major advantages of the polyphasic approach have also been described taking into account certain groups of bacteria as case studies to arrive at a consensus approach to microbial identification. [ABSTRACT FROM AUTHOR]

ABSTRACTThe marine environment is the most dynamic and most variable among the natural environments present on the globe due to its continuously changing patterns of salinity, sea surface temperature, pH, and pressure. Thus, bacteria inhabiting this environment possess the inbuilt mechanisms of adaptation necessary in such fluctuating environmental conditions, and the harboring of heavy metal–resistant genes adds to their efficiency with regard to metal remediation compared with their terrestrial counterparts. Two highly mercury-resistant isolates, one from the marine environment and another from steel industry waste, were identified asBacillus thuringiensisPW-05 andBacillussp. SD-43, respectively, by 16S rRNA gene sequence analysis. When various characters of these two isolates, e.g., biochemical, morphological, antibiotic resistance, and tolerance to other heavy metals, were analyzed, they were found to share common features. However, the marineBacillusisolate (PW-05) was found to be more capable than its terrestrial counterpart in terms of mercury volatilization capability, i.e., 94.72% in the case of PW-05 and 60.06% in the case of SD-43. Hence, marine bacteria can be used more efficiently than their terrestrial counterparts for enhanced bioremediation of mercury in contaminated envi-ronments. [ABSTRACT FROM PUBLISHER]

This study focused on: (i) feasibility of the previously developed sucrose ester stabilized SLNs and NLCs to encapsulate different imidazole antifungal drugs and (ii) preparation and evaluation of topical gel formulations of those SLNs and NLCs. Three imidazole antifungal drugs; clotrimazole, ketoconazole and climbazole were selected for this study. The results suggested that size, size distribution and drug encapsulation efficiency depend on the drug molecule and type of nanoparticles (SLN/NLC). The drug release experiment always showed faster drug release from NLCs than SLNs when the same drug molecule was loaded in both nanoparticles. However, drug release rate from both SLNs and NLCs followed the order of climbazole > ketoconazole > clotrimazole. NLCs demonstrated better physicochemical stability than SLNs in the case of all drugs. The drug release rate from ketoconazole- and clotrimazole-loaded SLNs became faster after three months than a fresh formulation. There was no significant change in drug release rate from climbazole-loaded SLNs and all drug-loaded NLCs. Gel formulations of SLNs and NLCs were prepared using polycarbophil polymer. Continuous flow measurements demonstrated non-Newtonian flow with shear-thinning behavior and thixotropy. Oscillation measurements depicted viscoelasticity of the gel formulations. Similar to nanoparticle dispersion, drug release rate from SLN- and NLC-gel was in the order of climbazole > ketoconazole > clotrimazole. However, significantly slower drug release was noticed from all gel formulations than their nanoparticle counterparts. Unlike nanoparticle dispersions, no significant difference in drug release from gel formulations containing SLNs and NLCs was observed for each drug. This study concludes that gel formulation of imidazole drug-loaded SLNs and NLCs can be used for sustained/prolonged topical delivery of the drugs. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop and evaluate solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) utilizing sucrose ester as a stabilizer/emulsifier for the controlled release of drug/active. Both SLNs and NLCs were prepared using different sugar esters to screen out the most suitable stabilizer. Clotrimazole was used as a model active/drug. The effect of different formulation variables on the particle size, polydispersity index and drug encapsulation efficiency of SLNs and NLCs was evaluated and compared. SLNs and NLCs were physicochemically characterized and compared using Cryo-SEM, DSC and XRD. Furthermore, a drug release study of SLNs and NLCs was conducted. Finally, physicochemical stability (size, PI, ZP, EE) of the SLNs and NLCs was checked at 25 ± 2 °C and at 2–8 °C. Among the sucrose esters, D-1216 was found to be most suitable for both SLNs and NLCs. Formulation variables exhibited a significant impact on size, PI and EE of the nanoparticles. SLNs with ∼120 nm size, ∼0.23 PI, ∼I26I mV ZP, ∼87% EE and NLCs with ∼160 nm size, 0.15 PI, ∼I26I mV ZP, ∼88% EE were produced. Cryo-SEM revealed spherical particles with a smooth surface but did not exhibit any difference in surface morphology between SLNs and NLCs. DSC and XRD results demonstrated the disappearance of clotrimazole peak(s) in drug-loaded SLNs and NLCs. Faster drug release was observed from SLNs than NLCs. NLCs were found to be more stable than SLNs in terms of size, PI, EE and drug release. The results indicated that both SLNs and NLCs stabilized with sucrose ester D-1216 can be used as controlled release carriers although NLCs have an edge over SLNs. [ABSTRACT FROM AUTHOR]

Abstract: Mercury exists naturally in small amounts in the environment as the sixteenth rarest element on earth. However, its level is rising due to industrialization and other anthropogenic activities such as the burning of coal and petroleum products, the use of mercurial fungicides in agriculture and the papermaking industry, and mercury catalysts in industries. Mercury-resistant bacteria harbor the mer operon in their genome. The mer operon includes certain functional genes along with promoter, regulator, and operator. The most common functional genes are merA and merB, which code for mercuric ion reductase and organomercurial lyase, respectively. The lyase is responsible for reducing highly toxic organomercurial compounds such as methylmercury and phenyl mercuric acetate into almost nontoxic volatile elemental mercury with the help of the enzyme reductase. When acting together in bacteria, merA and merB confer broad-spectrum mercury resistance. However, merA alone confers bacterial resistance to a narrow spectrum of inorganic mercury. This review discusses the importance of mercury-resistant bacteria harboring both merA and merB as potential agents in mercury bioremediation at highly polluted mercury-contaminated sites. [Copyright &y& Elsevier]

Abstract: In recent years, solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) are among the popular research topics for the delivery of lipophilic drugs. Although SLNs have demonstrated several beneficial properties as drug-carrier, limited drug-loading and expulsion of drug during storage led to the development of NLCs. However, the superiority of NLCs over SLNs has not been fully established yet due to the contradictory results. In this study, SLNs and NLCs were developed using clotrimazole as model drug. Size, polydispersity index (PI), zeta potential (ZP), drug-loading (L), drug encapsulation efficiency (EE), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffractometry (XRD), drug release and stability of SLNs and NLCs were compared. Critical process parameters exhibited significant impact on the nanoparticles’ properties. Size, PI, ZP and EE of the developed SLNs and NLCs were<100nm, <0.17, <−22mV and>82%, respectively. SEM images of SLNs and NLCs revealed spherical shaped particles (∼100nm). DSC and XRD studies indicated slight difference between SLNs and NLCs as well as disappearance of the crystalline peak(s) of the encapsulated drug. NLCs demonstrated faster drug release than SLNs at low drug-loading, whereas there was no significant difference in drug release from SLNs and NLCs at high drug-loading. However, sustained/prolonged drug release was observed from both formulations. Furthermore, this study suggests that the drug release experiment should be designed considering the final application (topical/oral/parenteral) of the product. Regarding stability, NLCs showed better stability (in terms of size, PI, EE and L) than SLNs at 25°C. Moreover, there was no significant difference in drug release profile of NLCs after 3months storage in compare to fresh NLCs, while significant change in drug release rate was observed in case of SLNs. Therefore, NLCs have an edge over SLNs. [Copyright &y& Elsevier]