Effect of silica nanoparticles on microbial biomass and silica availability in maize rhizosphere

The effect of silica nanoparticles and conventional silica sources on the changes in microbial biomass and silica availability to pure soil and maize rhizosphere was studied. Nanosilica (20-40 nm) was synthesized from rice husk and comprehensively characterized. The efficiency of nanosilica was evaluated in terms of its effects on beneficial microbial population such as phosphate solubilizers, nitrogen fixers, silicate solubilizers, microbial biomass carbon and nitrogen content, and silica content in comparison with other silica sources such as microsilica, sodium silicate, and silicic acid. Nanosilica significantly (P < 0.05) enhanced microbial populations, total biomass content (C = 1508 μg g(-1) and N = 178 μg g(-1) ), and silica content (14.75 mg mL(-1) ). Although microsilica sources enhanced factors associated with soil fertility, their use by maize roots and silicification in soil was found to be less. The results show that nanosilica plays a vital role in influencing soil nutrient content and microbial biota and, hence, may promote the growth of maize crop.

High prevalence of tobacco use, alcohol use and overweight in a rural population in Tamil Nadu, India

BACKGROUND

Cardiovascular diseases are one of the leading causes of death in India. There is high prevalence of cardiovascular risk factors in urban Tamil Nadu. There are limited data on the prevalence of behavioral risk factors and overweight in rural Tamil Nadu.

AIM

We estimated prevalence of behavioral risk factors, overweight and central obesity in a rural population in Tamil Nadu, India.

SETTING AND DESIGN

We conducted a cross-sectional survey in 11 villages in Kancheepuram/Thiruvallur districts, Tamil Nadu.

MATERIALS AND METHODS

Study population included 10,500 subjects aged 25-64 years. We collected data on behavioral risk factors and anthropometric measurements. Body mass index (BMI) was categorized using the classification recommended for Asians. Central obesity was defined as waist circumference ≥90 cm for men and ≥80 cm for women. We computed proportions for all risk factors and used trend chi-square to examine trend.

RESULTS

Among the 10,500 subjects, 4927 (47%) were males. Among males, 1852 (37.6%) were current smokers and 3073 (62.4%) were current alcohol users. Among females, 840 (15.1%) were smokeless tobacco users. BMI was ≥23.0 kg/m 2 for 1618 (32.8%) males and 2126 (38.2%) females. 867 (17.6%) males and 1323 (23.7%) females were centrally obese. Most commonly used edible oil was palm oil followed by sunflower oil and groundnut oil.

CONCLUSION

We observed high prevalence of tobacco use, alcohol use and central obesity in the rural population in Tamil Nadu. There is need for health promotion programs to encourage adoption of healthy lifestyle and policy interventions to create enabling environment.

Screening the UV-blocking and antimicrobial properties of herbal nanoparticles prepared from Aloe vera leaves for textile applications

Nanomaterials play a vital role in textile industries due to their unique properties and applications. There is an increase in the use of nanoscale phyto products in textiles to control the bacterial infection in fabrics. Here, natural herbal nanoparticles of different sizes were prepared from shade-dried Aloe vera plant leaves using ball milling technique without any additives. The amorphous herbal A. vera nanoparticles possess an average particle size of 40 ± 2 nm and UV-absorption maximum at 269 nm. A. vera nanopowders-chitosan nanocomposites were prepared and coated on cotton fabrics using pad-dry cure method. The evaluation of antibacterial activity against Escherichia coli (22.05 ± 0.06 mm) and Staphylococcus aureus (27.17 ± 0.02 mm), UV-protection properties (UV-protection factor = 57.2 ± 0.1), and superhydrophobic nature (155 ± 3°) of the prepared herbal nanoparticles and their composites were analysed by disc diffusion, UV-visible spectral analysis, and contact angle analysis. Understanding the functional properties of herbal nanoparticles, coated particles on fabrics highlights their potential applications in protective clothing with better antimicrobial properties, hydrophobicity, and UV-protection properties. This study of using A. vera herbal nanoparticles in textiles significantly enhances the fabric performance to develop protective textile fabrics in defence and biomedical fields.

Silicon confers protective effect against ginseng root rot by regulating sugar efflux into apoplast

Root rot caused by Ilyonectria mors-panacis is a devastating fungal disease leading to defect in root quality and causes reduced yield during the perennial life cycle of Panax ginseng Meyer. This indicates the imperative need to understand the molecular basis of disease development and also to enhance tolerance against the fungus. With this idea, the protective effect of silicon (supplied as silica nanoparticles) in P. ginseng root rot pathosystem and its molecular mechanism was investigated in the current study. We have tested different concentrations of silicon (Si) to disease-infected ginseng and found that long term analysis (30 dpi) displayed a striking 50% reduction in disease severity index upon the treatment of Si. Expectedly, Si had no direct degradative effect against the pathogen. Instead, in infected roots it resulted in reduced expression of PgSWEET leading to regulated sugar efflux into apoplast and enhanced tolerance against I. mors-panacis. In addition, under diseased condition, both protopanaxadiol (PPD) and protopanaxatriol (PPT) type ginsenoside profile in roots were higher in Si treated plants. This is the first report indicating the protective role of Si in ginseng-root rot pathosystem, thereby uncovering novel features of ginseng mineral physiology and at the same time, enabling its usage to overcome root rot.

In situ synthesised TiO2-chitosan-chondroitin 4-sulphate nanocomposites for bone implant applications

The artificial materials for bone implant applications are gaining more importance in the recent years. The series titania-chitosan-chondroitin 4-sulphate nanocomposites of three different concentrations (2:1:x, where x- 0.125, 0.25, 0.5) have been synthesised by in situ sol-gel method and characterised by various techniques. The particle size of the nanocomposites ranges from 30-50 nm. The bioactivity, swelling nature, and the antimicrobial nature of the nanocomposites were investigated. The swelling ability and bioactivity of the composites is significantly greater and they possess high zone of inhibition against the microorganisms such as Staphylococcus aureus and Escherichia coli. The cell viability of the nanocomposites were evaluated by using MG-63 and observed the composites possess high cell viability at low concentration. The excellent bioactivity and biocompatibility makes these nanocomposites a promising biomaterial for bone implant applications.

Towards optimal toe-clearance in synthesizing polycentric prosthetic knee mechanism

Stability at the stance phase and near normal able-bodied swing phase kinematics are essential in designing the prosthetic knee mechanism for transfemoral amputees. Primarily, insufficient mid swing toe clearance results in asymmetrical gait patterns, leading to muscular-skeletal pain and joint degeneration. The present work is focused on synthesizing a polycentric knee mechanism to enhance the toe-clearance at mid-swing for safe level ground walking of amputees in developing countries. Both fixed and moving centrodes of the four-bar knee mechanism are considered in optimal synthesis of the mechanism for achieving able-bodied gait patterns using evolutionary algorithms in mechanism design software tools. The knee stability at heel contact, stabilizing moment at push-off, stable knee flexion range, maximum knee flexion and maximum toe-clearance at mid-swing are the parameters used for comparing the knee design with the existing commercially available designs. The optimized results are then verified experimentally by building a functional prototype using a 3 D printing technique. The designed mechanism executes nominal performance in four parameters and offers enhanced toe-clearance during mid-swing. This is a significant improvement over the existing designs for amputees to navigate comfortably on irregular terrain in developing countries.

Biomimetic development of chitosan and sodium alginate-based nanocomposites contains zirconia for tissue engineering applications

Nanostructured materials possess unique structural and functional properties that play a crucial position in tissue engineering applications. Present investigation is aimed to synthesize chitosan-sodium alginate (CS) nanocomposite using hydrothermally prepared zirconia nanoparticles. In this, three different weight percentages of (0.5, 1, and 1.5) zirconia nanoparticles are utilized for the preparation of biomimetic nanocomposite scaffolds (CSZ) employing 4 wt% of CS by a solvent casting technique. Physico-chemical and thermal behavior of the prepared nanoparticles and their CSZ scaffolds are comprehensively characterized. Bioactivity of the prepared zirconia nanoparticles and CSZ scaffolds are explored in terms of in vitro biocompatibility, protein absorption in simulated body fluid (SBF), and phosphate buffered saline (PBS). Agar disc diffusion method is employed to identify the antibacterial property against Staphylococcus aureus and Escherichia coli. In vitro cytotoxicity of zirconia nanoparticles and CSZ scaffolds is identified against human urothelial carcinoma (UC6) and osteosarcoma (MG-63) cells. These studies explore that zirconia nanoparticles are suitable for biomedical applications while it is interacted with chitosan and sodium alginate (CS) due to their promising biocompatibility. Biomimetically obtained chitosan/sodium alginate scaffold contain 1 wt% zirconia nanoparticles show higher biocompatibility amenable for tissue engineering applications.

Evaluation of Oxidative Stress Parameters and Antioxidant Status in Coronary Artery Disease Patients

A surge in oxidative stress and weakened antioxidant defense contributes to the initiation and progression of Coronary Artery Diseases (CAD). The resultant burst in free radicals causes oxidation of lipoproteins mainly oxidized low-density lipoprotein (oxLDL). Further studies need to be conducted to find whether the management of CAD can be evaluated within the context of oxidant/antioxidant balance with the contribution of newer markers. This study was performed to evaluate, compare, and correlate oxidative stress parameters and antioxidant status in CAD patients with controls and evaluate and compare pro-oxidant, a pro-inflammatory enzyme, myeloperoxidase (MPO) and anti-oxidant, anti-inflammatory enzyme, and paraoxonase (PON) between CAD patients and controls. OxLDL, an oxidation product of low-density lipoprotein, malondialdehyde (MDA), an oxidative marker, and reduced glutathione (GSH), an anti-oxidant marker, and lipid profile were assessed and compared in CAD patients and controls. The activity of MPO was correlated with that of PON, and MDA level was correlated with GSH level. A total of 100 clinically proven CAD patients, in the age range of 35-70 years, were selected from the Out Patient Department (OPD) of our Institute. A total of 60 controls in the same age range and without CAD were selected after undergoing health checkups in the hospital. Based on the obtained results, oxLDL, MDA, and MPO were significantly increased in patients than in controls (P<0.05), and PON and GSH were significantly lowered in patients than in controls (P<0.05). Total cholesterol, triglyceride, and LDL were significantly high in CAD patients. A significant negative correlation was observed between MPO and PON levels and between MDA and GSH levels. Increased oxidative stress and decreased antioxidant status were observed in patients with CAD. Formation of oxLDL increased MPO and decreased PON are all additional risk factors for the development of CAD and can be targeted for future therapeutic purposes. Lifestyle modifications and treatment methods can reduce CAD risk through the reduction of oxidative stress and improvement of antioxidant status.

RGO nanosheet wrapped β-phase NiCu2S nanorods for advanced supercapacitor applications

A new integration strategy of transition metal sulfide with carbon-based materials is used to boost its catalytic property and electrochemical performances in supercapacitor application. Herein, crystalline reduced graphene oxide (rGO) wrapped ternary metal sulfide nanorod composites with different rGO ratios are synthesized using hydrothermal technique and are compared for their physical, chemical, and electrochemical performances. It is found that their properties are tuned by the weight ratios of rGO. The electrochemical investigations reveal that β-NiCu₂S/rGO nanocomposite electrode with 0.15 wt.% of rGO is found to possess maximum specific capacitance of 1583 F g^-1 at current density of 15 mA g^-1 in aqueous electrolyte medium. The same electrode shows excellent cycling stability with capacitance retention of 89% after 5000 charging/discharging cycles. The reproducibility test performed on NiCu₂S/rGO nanocomposite electrode with 0.15 wt.% of rGO indicates that it has high reproducible capacitive response and rate capability. Thus, the present work demonstrates that the β-NiCu₂S/rGO nanocomposite can serve as a potential electrode material for developing supercapacitor energy storage system.

Perception of Organizational Climate

It was hypothesized that the perceptions of climate by workers and employers and the perceptions of members of different levels of productivity would differ. Such differences, it was hypothesized, are mediated through the vulnerability of the items of climate described emotionally. An analysis of variance of the response of workers and employers of hosiery units 15 high and 15 low in productivity and correlations between responses of workers and employers on Likert's climate scale items support the first and last hypotheses.

Curcumin loaded gold nanoparticles-chitosan/sodium alginate nanocomposite for nanotheranostic applications

A solvent casting technique was used for the preparation of biomimetic nanocomposites scaffolds at three various concentrations of Curcumin loaded gold nanoparticles (Cur-AuNPs-1, 1.5, and 2 ml) as filler materials with chitosan-sodium alginate composite. The physico-chemical properties of prepared Cu-Au NPs and biomimetic nanocomposites were analyzed using various characterization techniques. In vitro biocompatibility of biomimetic nanocomposites are determined using simulated body fluid for biomineralization property, HAp formation and phosphate buffer saline (PBS) for swelling property, protein adsorption. Antibacterial activity of Cur-Au NPs and their nanocomposites carried out against Escherichia coli (E. coli) and Staphylococcus aureus. In vitro cytotoxicity of Cur-AuNPs is identified against UC-6 and MDA-MB 231 cell lines. The use of above studies and activity of Cur-AuNPs with contain biomimetic nanocomposites can adoptable for nanotheranostics.