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Prodigiosin finds tremendous application in the food industry owing to its physicochemical and non-toxic attributes. In the present investigation, microbial production of food color (prodigiosin) was done by Serratia marcescens NCIM 5246 under solid-state fermentation (SSF). For economical prodigiosin yield, initial substrate screening was conducted using agro-waste such as rice bran, wheat bran, orange peel powder, green gram husk and cane molasses. A maximum pigment yield of 1059.67 ± 1.53 µg/L was observed on wheat bran media. Further, Taguchi Design of the experiment (DOE) using Qualitek-4 software with bigger is better as quality attributes was done for process optimization. The Taguchi (DOE) comprised five independent variables, i.e., pH, temperature, substrate concentration, trace metal concentration, and inoculum size at two levels. The software deduced independent variables' individual and interactive effects on product yield by performing an L8 orthogonal array (OA). The output variable (prodigiosin yield) was improved based on the S/N ratio. Under optimized cultural conditions maximum prodigiosin yield of 1320.2 ± 20 µg/L was obtained. The expected prodigiosin yield of 1386.60 µg/L showed a 95% resemblance with the actual yield, showed model validation, and 24.57% improvement in overall yield. The extracted pigment was purified by TLC and was characterized as prodigiosin by absorption spectroscopy and FTIR. [ABSTRACT FROM AUTHOR]

In this research work, composite mixtures of TiO2 (anatase) and silver were investigated. The nano-scaled sample powders of anatase-TiO2 and Ag were synthesised using ultrasonic assisted sol-gel method and top-down method respectively. The content of silver was increased gradually to observe its effect on varistor properties of TiO2 nanopowders. Structural and surface analysis were done using various characterisation. TGA gave the calcination temperature at 450 °C in order to obtain anatase form. Slender tetragonal structure belonging to D 4 h 19 I41/amd space group and cubic structure in O h 5 Fm 3 m space group were obtained for TiO2 and Ag respectively. These results were confirmed from XRD and Raman Analysis. FESEM exhibited spherical shape for TiO2 nanopowders and also showed the cluster formation of Ag. Current versus voltage graphs were obtained to examine the extent of applicational prospects and it was observed that TiO2 sample mixtures gave small increase in current voltage values when used with single conductive material. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are added to the matrix according to proper distribution configurations by many researchers to improve the stiffness of laminated composites. However, the distribution configurations of CNTs may induce dramatic changes in displacements and stresses, which significantly affect structural safety. Moreover, such issues have received little attention at present because existing theoretical models encounter difficulties in accurately predicting dramatic changes in stresses of these structures. To accurately analyze the thermal expansion behaviors of laminated panels reinforced by CNTs, an equivalent single-layer higher-order model is proposed in which in-plane displacements are constructed by superimposing the second local displacements onto a smooth cubic varying field. Transverse normal deformation should be considered for the thermal expansion behavior of the laminated plate; therefore, a smooth cubic distribution along the thickness is adopted in the transverse displacement field. The layer-dependent displacement parameters can be expressed using global displacement variables by applying compatible conditions of displacements and stresses. Based on the proposed model, analytical solutions for laminated composites are obtained using Navier's technique. The capability of the proposed model is verified by comparing the results of the proposed model with the exact solutions and the three-dimensional finite element model. The effect of the distribution configuration and volume fraction of CNTs on the thermomechanical behavior of the composite panels is studied based on the present model. Numerical results show that the distribution configuration and volume fraction of the CNTs significantly influence the distributions and magnitudes of stresses. Practical Applications: In order to improve the stiffness of aircraft wings, stiffeners are typically used to enforce the skin of the wing. However, the aerodynamic shape of the wing cannot be changed, so that the stiffeners cannot be placed on external surface of the skin. As a result, the panel's bending stiffness relative to the midplane is not asymmetric, which affected its loading capability. To overcome such problems, previous studies have demonstrated that adding CNTs can improve the stiffness of panels, and it has been found that composite panels reinforced with X-X-distributing CNTs possess the best capability in preventing buckling deformation. However, the effect of the distribution profiles of CNTs on the thermomechanical behavior has been less studied in the existing literature. Therefore, this study proposes a higher-order model to accurately predict the thermomechanical behavior of CNT-reinforced composite panels and investigate the effect of CNT distribution profiles and volume fractions on the thermomechanical responses of composite panels. The present work can provide suggestions for the design of a reinforcing scheme for CNT-reinforced composite panels, so that the stiffness of wings can be enhanced. [ABSTRACT FROM AUTHOR]

A comprehensive study has been carried out to understand the details of structural modifications of polyallyl diglycol carbonate (PADC) polymer under the effects of different external factors. Synergistic effect of heat treatment with radiation on the polymer structure was studied. Incorporation of a neutral chromophore to understand the structural changes was attempted. Theoretical simulations were applied to get insight into the detailed aspects of structural modifications. Diverse techniques were used to characterize the samples and compare with the results of simulation studies. [ABSTRACT FROM AUTHOR]

Prodigiosin (PG) is a red tripyrrole pigment from the prodiginine family that has attracted widespread attention due to its excellent biological activities, including anticancer, antibacterial and anti-algal activities. The synthesis and production of PG is of particular significance, as it has the potential to be utilized in a number of applications, including those pertaining to clinical drug development, food safety, and environmental management. This paper provides a systematic review of recent research on PG, covering aspects like chemical structure, bioactivity, biosynthesis, gene composition and regulation, and optimization of production conditions, with a particular focus on the biosynthesis and regulation of PG in Serratia marcescens. This provides a solid theoretical basis for the drug development and production of PG, and is expected to promote the further development of PG in medicine and other applications. [ABSTRACT FROM AUTHOR]

MXene-based nanofluids are important because of their thermal and rheological properties, influencing scientific and industrial applications. MXenes, made of titanium carbides and nitrides, are investigated for nanofluid enhancement. This review covers MXene nanofluid creation, characterization, and application. To produce nanoscale MXene particles, two-dimensional materials are dissolved and dispersed in a base fluid. The stability and efficacy of MXene nanofluids depend on production methods, such as chemical exfoliation, electrochemical etching, and mechanical delamination. Improved heat transfer coefficients and thermal conductivity from MXene nanofluids help resolve heat transfer, energy efficiency, and thermal control problems. This extensive review also addresses long-term safety and the necessity for standardized characterization methodologies, helping researchers optimize MXene-based nanofluids in many technological fields. [ABSTRACT FROM AUTHOR]

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With the impact of the COVID-19 outbreak, almost all scientists and nations began to show great interest in the subject for a long time. Studies in the field of outbreak, diagnosis and prevention are still ongoing. Issues such as methods developed to understand the spread mechanisms of the disease, prevention measures, vaccine and drug research are among the top priorities of the world agenda. The accuracy of the tests applied in the outbreak management has become extremely critical. In this study, it is aimed to obtain a function that finds the positive or negative COVID-19 test from the blood gas values of individuals by using Machine Learning methods to contribute to the outbreak management. Using the Multivariate Linear Regression (MLR) model, a linear function is obtained to represent the COVID-19 dataset taken from the Van province of Turkey. The data set obtained from Van Yüzüncü Yıl University Dursun Odabaş Medical Center consists of blood gas analysis samples (109 positive, 1146 negative) taken from individuals. It is thought that the linear function to be obtained by using these data will be an important method in determining the test results of individuals. Gradient Descent optimization methods are used to find the optimum values of the coefficients in the function to be obtained. In the study, the RMSProp optimization algorithm has a success rate of 58-91.23% in all measurement methods, and it is seen that it is much more successful than other optimization algorithms. [ABSTRACT FROM AUTHOR]

In this work, polyolefin‐blend/clay nanocomposites based on low‐density polyethylene (LDPE), linear low‐density polyethylene (LLDPE), and organically modified clay (OC) were prepared by melt extrusion. Various grades of maleic anhydride (MA) grafted polyethylene (PE‐g‐MA) were used and examined as compatibilizers in these nanocomposites. Differential scanning calorimetry analysis showed that OC and compatibilizer affect the crystallization behavior of LDPE/LLDPE with different mechanisms. Thermodynamic calculations of wetting coefficient based on interfacial energy between OC, LD, and LL, Morphological characterization based on field emission scanning electron microscopy, X‐ray diffraction, small angles X‐ray scattering, and dynamic rheology measurements revealed that the compatibilizer and OC were localized at the interface of LDPE and LLDPE phases with a preferred tendency toward one phase. Results demonstrated that at a specific amount of OC, there is an optimum compatibilizer concentration to achieve nanodispersed OC and beyond that the compatibilizer causes a structural change in the polymer crystalline morphology. It was also found that the tensile property enhancement of LDPE/LLDPE/OC nanocomposites is closely related to the crystalline structure development made by incorporation of both OC and compatibilizer. [ABSTRACT FROM AUTHOR]

The present study was conducted to evaluate twenty four (24) genotypes along with 1 check variety (Pusa Navbahar) of cluster bean during kharif, July–September, 2019 at College of Horticulture, Rajendranagar, Sri Konda Laxman Telangana State Horticultural University, Telangana, India to estimate variability, broad sense heritability and genetic advance for pod yield and yield attributing traits. The observations were recorded on various growth, yield and quality parameters. High estimates of GCV and PCV were recorded for plant height, number of branches plant-1, pod length, pod weight and number of pods plant-1. Protein content, gum content and fibre content recorded moderate to high PCV and GCV. High heritability coupled with high genetic advance as % of mean was observed for plant height, number of branches plant-1, number of clusters plant-1, days to maturity, number of pods plant-1, pod length, pod girth, pod weight, number of seeds pod-1, pod yield plant-1, pod yield ha-1, protein content, gum content and fibre content. High variability in conjunction with high genetic advance as % of mean indicating the predominance of additive gene action. These traits could be exploited through manifestation of dominance and epistatic components through heterosis breeding. The overall assessment showed that there was wide variability among cluster bean genotypes which has important implication for selection of cluster bean genotypes for yield and quality attributes. [ABSTRACT FROM AUTHOR]

Bionanocomposites based on natural bioactive entities have gained importance due to their abundance; renewable and environmentally benign nature; and outstanding properties with applied perspective. Additionally, their formulation with biological molecules with antimicrobial, antioxidant, and anticancer activities has been produced nowadays. The present review details the state of the art and the importance of this pyrrolic compound produced by microorganisms, with interest towards Serratia marcescens, including production strategies at a laboratory level and scale-up to bioreactors. Promising results of its biological activity have been reported to date, and the advances and applications in bionanocomposites are the most recent strategy to potentiate and to obtain new carriers for the transport and controlled release of prodigiosin. Prodigiosin, a bioactive secondary metabolite, produced by Serratia marcescens, is an effective proapoptotic agent against bacterial and fungal strains as well as cancer cell lines. Furthermore, this molecule presents antioxidant activity, which makes it ideal for treating wounds and promoting the general improvement of the immune system. Likewise, some of the characteristics of prodigiosin, such as hydrophobicity, limit its use for medical and biotechnological applications; however, this can be overcome by using it as a component of a bionanocomposite. This review focuses on the chemistry and the structure of the bionanocomposites currently developed using biorenewable resources. Moreover, the work illuminates recent developments in pyrrole-based bionanocomposites, with special insight to its application in the medical area. [ABSTRACT FROM AUTHOR]

Among the natural antagonistic microorganisms of plant-parasitic nematodes are rhizobacteria of the genus Serratia. Some species can produce a red pigment known as prodigiosin, which has shown to be antagonistic to different organisms. We analysed the nematicidal potential of this metabolite obtained from a Serratia marcescens strain on the nematode, Nacobbus celatus. In the first experiment, mortality of second-stage juveniles (J2) from two Argentine populations (Río Cuarto and Santa María from Córdoba and Catamarca provinces, respectively) was estimated at different concentrations of the metabolite at 24 and 48 h in vitro. Based on the percentages obtained, lethal doses 50 (LD50) and 90 (LD90) were determined. LD50 for Río Cuarto and Santa María was 12.4 and 13.2 μg/mL, respectively, whereas LD90 was 24.9 μg/mL for both populations. In the second experiment, both LDs were applied in the soil and at 12 days after inoculation, J2 that had penetrated tomato roots were counted. The application of prodigiosin to the soil reduced nematode root invasion by 59% (LD50) and 83% (LD90) with respect to control. Our in vivo results also evidence the efficacy of the compound in the soil at very low concentrations. The pigment reveals, for the first time, to be an alternative method for biological control of N. celatus. [ABSTRACT FROM AUTHOR]

Prodigiosin is a promising food color due to its antibacterial, antimalarial, antimycotic characteristics, immunomodulating, and antitumor activities. Novel prodigiosin producing strain isolated from sugarcane field soil of Banaras Hindu University, India, characterized as Serratia marcescens bhu prodig by 16 sRNA. The effect of carbon, nitrogen source, and physical parameters (pH and temperature) on pigment yield was studied. The highest amount of pigment produced, which was 800.95 ± 0.05 mg/L, was detected when sorbitol and peptone were used as nitrogen and carbon source with pH 7 at 30 °C. The optimized condition scale-up in a bioreactor with a working capacity of 3.0 L, gave maximum pigment yield of 825 ± 0.05 mg/L with µ (Maximum specific growth rate), Yp/x, which represents the product yield coefficient, and Yp/s, which signifies the specific product yield coefficient and productivity of 0.3/h, 0.62, 0.80, and 0.02 g/L/h, respectively, after 72 h of cultivation in submerged fermentation (SMF). The isolated pigment was characterized as prodigiosin by the analysis of spectral data and GC-MS. The mass spectrophotometry investigation characterized pigment as 4-methoxy-5(5 methyl-4-pentyl-2H-pyrrol-2-ylidene)- 2,2-bipyrrole ring structure. The GC-MS chromatogram showed m/z of 323, representing prodigiosin. The prodigiosin yield and productivity obtained in the current finding were higher than in previous reports., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Thirty five chilli genotypes were evaluated in a randomized block design at College of Horticulture, Rajendranagar, Sri Konda Laxman Telangana State Horticultural University, Hyderabad, Telangana state, India during Kharif, 2019 for seven months and at National Bureau of Plant Genetic Resources, Regional station, Rajendranagar, Hyderabad during Rabi 2019-20 for seven months to estimate genetic variability, heritability, genetic advance and genetic advance as % of mean of seventeen yield and yield related traits. For all the traits studied, the magnitude of PCV was higher than corresponding GCV. High Phenotypic coefficient of variation and genotypic coefficient of variation estimates were recorded for plant height, plant spread, fruit length, fruit diameter, number of fruits plant-1, fruit weight, fruit yield plant-1, fruit yield plot-1, ascorbic acid, capsaicin content and capsanthin content indicating the existence of wider genetic variability for these traits in the genotypes studied. High heritability was recorded for the traits Days to first flowering, Fruit length, Fruit diameter, No. of fruits plant-1, Fruit weight, Fruit yield plant-1, Fruit yield plot-1, Ascorbic acid, Chlorophyll content, Capsaicin content and Capsanthin content. High heritability coupled with high genetic advance as % mean indicates existence of additive gene action which was observed in fruit length, fruit diameter, number of fruits plant-1, fruit weight, fruit yield plant-1, fruit yield plot-1, ascorbic acid, chlorophyll content, capsaicin content and capsanthin content. Hence these traits can be improved by direct selection. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) infections are a major global health problem, and novel and effective antimicrobial drugs are urgently required to combat this life-threatening pathogen. Prodigiosin (PG) is a bacterial secondary metabolite with excellent anticancer and antibacterial properties. However, little is known about the antibacterial function of PG against MRSA. Therefore, the antibacterial efficacy of PG alone and PG in combination with different metal ions against clinic isolates of MRSA and methicillin-sensitive S. aureus (MSSA) strain was evaluated in the present study. The minimum inhibitory concentration of PG against both MRSA and MSSA was 0.25 μg/mL. However, 0.1 μg/mL PG showed a stronger inhibitory effect on MSSA cell growth (47.12%) than on MRSA cell growth (35.87%). Surprisingly, we observed a significant difference (p < 0.01) in membrane integrity between PG-treated MRSA and MSSA using the propidium iodide staining assay. Further, we found that in combination with PG, Zn2+, Al3+, and Cu2+ showed synergistic antibacterial effects against MRSA and MSSA. Our results could increase the current knowledge regarding the efficacy of PG in inhibiting the growth of different types of S. aureus clinical isolates and also offer a novel strategy for developing efficient antibacterial agents. [ABSTRACT FROM AUTHOR]

Polyetheretherketone (PEEK) composites exhibit high stiffness, chemical stability, and heat resistance and they are therefore employed in applications under severe operating environments. This work aims to provide insight into the effect of the size, concentration, and type of fillers on the thermal and mechanical properties of PEEK. A total of 32 composites are used to highlight the influence of nature (lamellae, such as boron nitride and graphite and silicon carbide and alumina), size (nano and micrometric), and content (2.5, 5, 7.5, and 10 vol%) of fillers. The melting temperature and lamellar thickness did not change regardless of the nature of the filler. The thermomechanical analysis demonstrates that lamellar fillers form a percolating network and contribute significantly to the enhancement of the storage modulus. The increase in the storage modulus is proportional to the filler content, and it is more pronounced for micro composites. As expected, the percolating network is formed at lower concentrations for lamellar fillers than for spherical ones. The highest conductivity is achieved with graphite at 0.823 W m−1 K−1, which is twice that of PEEK for 10 vol%. Moreover, the use of micrometric fillers results in thermal conductivity enhancement attributed to the higher amount of efficient hot zones for heat transfer. [ABSTRACT FROM AUTHOR]

Prodigiosin is a red color pigment extracted by the bacterium Serratia marcescens and it has antimicrobial and antioxidant properties. In this study, the effects of different concentrations (1.5, 2%) of prodigiosin on the shelf life and quality of crap fillet during chilled storage (4+1 °C) were examined over a period of 18 days. The treatment were analyzed on days 0, 3, 6, 9, 12, 15, and 18 by bacteriological (total viable counts (TVC), total psychrotrophic counts (PTC) and lactic acid bacteria (LAB)) and biochemical (Peroxide value (PV), Thiobarbithic acid (TBA), free fatty acid (FFA), and pH) tests. Prodigiosin at 2% efficiently retarded lipid oxidation by decreasing PV, FFA and TBA production in the samples and it had the lowest pH, TVC, PTC and LAB, as well as this treatment had acceptable microbial parameters attributes up to eighteenth days of storage period. According to result prodigiosin with 2% concentration canrecommended as a natural antimicrobial and antioxidant in meat products. [ABSTRACT FROM AUTHOR]

ZnO-based varistor ceramics doped with different amount of Y2O3 have been made by two-step solid-state reaction route including the pre-calcination and subsequent sintering procedures, using nanosized ZnO powder and corresponding additives as the raw material. The phase composition, microstructure and electrical properties were studied by means of X-ray diffractometry (XRD), scanning electron microscopy (SEM) and direct current electrical measurement. It was found that the electrical properties of the varistor ceramics sintered at 950 °C from the powder pre-calcined at 800 °C were enhanced by doped appropriate amount of Y2O3. Particularly, ZnO varistors doped with 1.2 mol% Y2O3 possessed the best comprehensive electrical properties with the breakdown field of 2113 V/mm, the nonlinear coefficient of 184.6 and the leakage current of 0.4 μA. Y2O3 phase, Y-rich phase and the other secondary phase particles were confirmed to distribute along the grain boundaries of predominant ZnO grains from XRD and SEM analyses. The results illustrated that doping Y2O3 should be a promising route to obtain varistor ceramics with excellent electrical properties. [ABSTRACT FROM AUTHOR]

An interval type-2 fuzzy logic system (IT2FLS) can function well with uncertain data, with which a type-1 fuzzy logic system (T1FLS) is ineffective because its membership function rests upon crisp values. However, similar to T1FLSs, there are challenges associated with IT2FLSs in selecting parameters, which can significantly affect the accuracy of the classification results with their relatively high sensitivity. This paper discusses and proposes a hybrid model based on IT2FLS and particle swarm optimization (PSO) for prediction problems. The main objective of this paper is to find the optimal solution for the unknown fuzzy systems using labelled data for training the fuzzy system. The PSO technique was used to find the optimal parameters of the Gaussian membership functions which utilized for IT2FLSs. The authors tested two data sets for each of the two prediction problems, namely: burnt forest area prediction and wine quality prediction. The predictive results were compared with other predictive methods including random forest (RF), support vector machines (SVM), artificial neural network (ANN), adaptive neuro fuzzy inference system (ANFIS) and IT2FLS with parameters generated by using the fuzzy c-means algorithm (IT2FLS-FCM). Experiment results showed that the proposed method could significantly improve accuracy compared to several other predictive techniques. [ABSTRACT FROM AUTHOR]