Histomorphological perspectives of preputial and clitoral glands of soft-furred field rat Millardia meltada

The present study was an attempt to understand the sexual dimorphism of the integumentary scent glands of soft-furred fi eld rat Millardia meltada from the perspectives of anatomy, morphology and histology with view to correlate with the sex-specifi c pheromones they produce. The scent gland of male is known as preputial gland, and female, the clitoral gland. The rats, that are agricultural pests were fi eld caught, the glands of males and females of almost identical size were dissected out, and subjected to gravimetric, morphometric and histological analyses. Both glands are yellowish-brown, pear-shaped, and dorsoventrally compressed. The mean weight, length and width of preputial glands are signifi cantly (p < 0.05) larger than that of the clitoral glands. The preputial gland is composed of sebaceous glandular lobules and apocrine glandular lobules whereas the clitoral gland is formed only of sebaceous glandular lobules. The sebaceous glandular lobules of both preputial and clitoral glands are fi lled with a wax-like material. Thus, the scent glands of the soft-furred male fi eld rats exhibit sexual dimorphism in respect histoarchitecture of the glands and the nature of the secretory material. This sexual dimorphism of the scent glands may refl ect control by male and female sex hormones impinging on specifi c roles as sex attractant pheromones

Purification and characterization of chitinase from Alcaligenes faecalis AU02 by utilizing marine wastes and its antioxidant activity

Marine waste is an abundant renewable source for the recovery of several value added metabolites with potential industrial applications. This study describes the production of chitinase on marine waste, with the subsequent use of the same marine waste for the extraction of antioxidants. A chitinase-producing bacterium isolated from seafood effluent was identified as Alcaligenes faecalis AU02. Optimal chitinase production was obtained in culture conditions of 37°C for 72 h in 100 ml medium containing 1% shrimp and crab shell powder (1:1) (w/v), 0.1% K2HPO4, and 0.05% MgSO4·7H2O. The molecular weight of chitinase was determined by SDS-PAGE to be 36 kDa. The optimum pH, temperature, pH stability, and thermal stability of chitinase were about 8, 37°C, 5–12, and 40–80°C, respectively. The antioxidant activity of A. faecalis AU02 culture supernatant was determined through scavenging ability on 1,1-diphenyl-2-picrylhydrazyl (DPPH) as 84%, and the antioxidant compound was characterized by TLC and its FT-IR spectrum. The present study proposed that marine wastes can be utilized to generate a high-value-added product and that pharmacological studies can extend its use to the field of medicine

Fault‐alarm based hybrid control design for uncertain periodic piecewise time‐varying systems with actuator constraints

International audienceThis paper is concerned with the stabilization problem for continuous-time periodic piecewise time-varying uncertain systems with time-varying delay, actuator failures and external disturbances. Specifically, the actuator failure consists of both unknown actuator partial failure and actuator bias failure. Based on multiple threshold values, in this work, a fault-alarm based hybrid control protocol is developed, which is used to switch between robust and reliable controllers accurately and timely by eliminating false alarms. To be precise, a set of sufficient stability criteria is established in the form of linear matrix inequalities (LMIs) by considering an appropriate Lyapunov-Krasovskii functional with time-varying periodic piecewise positive-definite matrices. Furthermore, the desired time-varying robust and reliable controller gain matrices can be reckoned based on developed LMI-based constraints. Eventually, two numerical examples are presented, which include the mass-spring damper systems, to show the superiority and practicability of the designed controller

Flexible quasi-solid-state lithium-ion capacitors employing amorphous SiO2 nanospheres encapsulated in nitrogen-doped carbon shell as a high energy anode

Lithium-ion hybrid capacitors (LICs) take the advantage of simultaneous high energy – power output, and become increasingly important for next generation applications. Developing a high performing LICs with high energy-power-cycle combination remains a significant challenge due to low capacity intercalation electrodes, and kinetically sluggish alloying type electrodes. A strategy employing fast pseudocapacitive lithium ion storage in high-capacity alloying type anode, rather than a bulk storage, can output kinetically superior LICs with high energy even at high power conditions. Herein, we demonstrate a highly interconnected 3-dimensional (3D) SiO2 nanospheres embedded Nitrogen-doped carbon shell with fast lithium ion storage kinetics as high performing anode for LICs. As a result, LIC with a high energy (139 Wh kg−1), high power density (42 kW kg−1), and super stability (20,000 cycles) is obtained, outperforming previously studied alloying type metal oxide and sulfide anodes. A flexible LICs is further demonstrated which shows good stability under different bending conditions. The current research promotes the practical utilization of earth-abundant material as a high capacity and high rate electrode for the next-generation flexible and wearable devices. © 20201

Hierarchical Self-Assembly of Bile-Acid-Derived Dicationic Amphiphiles and Their Toxicity Assessment on Microbial and Mammalian Systems

A thiol-yne click chemistry approach was adopted for the first time to prepare highly water-soluble bile acid derived dicationic amphiphiles. The synthesized amphiphiles dicationic cysteamine conjugated cholic acid (DCaC), dicationic cysteamine conjugated deoxycholic acid (DCaDC), and dicationic cysteamine conjugated lithocholic acid (DCaLC) exhibited hierarchically self-assembled microstructures at various concentrations in an aqueous medium. Interestingly at below critical micellar concentration (CMC) the amphiphiles showed distinct fractal patterns such as fractal grass, microdendrites and fern leaf like fractals for DCaC, DCaDC and DCaLC respectively. The fractal dimension (Df) analysis indicated that the formation of fractal like aggregates is a diffusion limited aggregation (DLA) process. The preliminary aggregation studies such as determination of CMC, fluorescence quenching, wettability and contact angle measurements were elaborately investigated. The morphology of the aggregates were analyzed by SEM and OPM techniques. Further, we demonstrated the antimicrobial and hemolytic activity for the cationic amphiphiles. DCaC had potent antimicrobial activity and showed no toxicity on human RBCs indicating that DCaC could be used in biomedical applications, in addition to their industrial and laboratory applications such as detergency, surface cleaning, and disinfection agent

Sodium Cholate-Templated Blue Light-Emitting Ag Subnanoclusters: <i>In Vivo</i> Toxicity and Imaging in Zebrafish Embryos

We report a novel green chemical approach for the synthesis of blue light-emitting and water-soluble Ag subnanoclusters, using sodium cholate (NaC) as a template at a concentration higher than the critical micelle concentration (CMC) at room temperature. However, under photochemical irradiation, small anisotropic and spherically shaped Ag nanoparticles (3–11 nm) were obtained upon changing the concentration of NaC from below to above the CMC. The matrix-assisted laser desorption ionization time-of-flight and electrospray ionization mass spectra showed that the cluster sample was composed of Ag₄ and Ag₆. The optical properties of the clusters were studied by UV–visible and luminescence spectroscopy. The lifetime of the synthesized fluorescent Ag nanoclusters (AgNCs) was measured using a time-correlated single-photon counting technique. High-resolution transmission electron microscopy was used to assess the size of clusters and nanoparticles. A protocol for transferring nanoclusters to organic solvents is also described. Toxicity and bioimaging studies of NaC templated AgNCs were conducted using developmental stage zebrafish embryos. From the survival and hatching experiment, no significant toxic effect was observed at AgNC concentrations of up to 200 μL/mL, and the NC-stained embryos exhibited blue fluorescence with high intensity for a long period of time, which shows that AgNCs are more stable in living system

Recent developments and strategies in genome engineering and integrated fermentation approaches for biobutanol production from microalgae

© 2020 Elsevier LtdThe major hurdles causing difficulties in mechanized transportation are the depletion of fossil fuels and the high cost of alternative plant-based substrates for producing biofuels. To solve these issues, biofuels were emerged as effective alternatives to reduce pollution caused by the emission of greenhouse gases. Among biofuels, biobutanol is gaining attention as a feasible, renewable, cost-effective, alternative fuel. But the usages of conventional agricultural crops as feedstock are sensitive and controversial due to the growing concern over the availability of food worldwide. Microalgae are an excellent resource to overcome these challenges, which grows on both the sea and freshwater. Microalgae reducing their land usage with agriculture, and there is no food and fuel conflict exist. In addition, microalgae utilize inorganic carbon from the atmosphere for growth; hence they can reduce the emission levels as well as produce clean energy. Therefore, microalgae as third-generation feedstock came into practice due to their fast growth rate and higher carbohydrate content. The main focus of the present review is to discuss in detail about the major challenges faced as a feedstock, genetic engineering strategies adopted and future perspectives to improve the production of biobutanol from microalgae

Localization of α 2u-globulin in the acinar cells of preputial gland, and confirmation of its binding with farnesol, a putative pheromone, in field rat (Millardia meltada).

Pheromones, low molecular weight chemical entities that bind to pheromone carrier proteins, are chemical signals that play an important role in the communication system in animals. This has been rather fairly well-studied in the rodents. The preputial gland, a rich source of pheromones in many rodents, contains a low molecular mass protein (18-20 kDa) that acts as one such pheromone carrier. However, the presence of this protein in the notorious rodent pest Millardia meltada has not yet been proven. Therefore, we aimed at identifying this protein, and the pheromones that are bound to it, in this rodent so as to utilize the information in the control of this pest. Twenty volatile compounds were identified in the preputial gland using GC-MS. Total protein of the gland was fractioned by both one and two-dimensional electrophoresis when we identified a low molecular mass protein (19 kDa, pI-4.7). Adopting MALDI-TOF MS and LC-MS analyses, the protein was confirmed as α 2u-globulin. To identify the volatiles bound to this protein, we used column chromatography and GC-MS. We found that farnesol and 6-methyl-1-heptanol are the volatiles that would bind to the protein, which we propose to be putative pheromones. Immunohistochemical analysis confirmed localization of α 2u-globulin in the acinar cells of the preputial gland. Thus, we show that α 2u-globulin, a pheromone-carrier protein, is present in the preputial gland acinar cells of M. meltada and suggest farnesol and 6-methyl-1-heptanol to be the volatiles which would bind to it. The α 2u-globulin together with farnesol and 6-methyl-1-heptanol contribute to pheromonal communication of M. meltada