BIOGENIC SYNTHESIS SILVER NANOPARTICLES USING PELTOPHORUM PTEROCARPUM LEAF EXTRACTS AND ITS ANTIMICROBIAL EFFICACY AGAINST SELECTIVE PATHOGENS

Objective: The present study was aimed to screen silver nanoparticles (AgNPs) using different plant extracts and also to study their antimicrobial property against different human pathogens.Methods: Nine different plants, namely Parthenium hispidum, Vinga rose, Catheranthus roseus, Phyllanthus amarus, Azadirachta indica, Jatropa curcas, Tectona grandis, Ocimum sanctum, and Peltophorum pterocarpum were screened for the synthesis of AgNPs. The AgNPs were synthesized using leaf extracts and was well characterized using a UV-Visible spectrophotometer, transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and zeta potential measurement. The AgNPs was tested for their antibacterial and antifungal efficacy using agar well diffusion method.Results: Among the nine different plant extracts screened, AgNPs synthesized using Peltophorum pterocarpum leaf extract showed good stability even after one month with maximum absorption spectra of 425 nm. The synthesized AgNPs was found to be spherical in shape with an average size ranging from 20 to 60 nm. The EDX spectrum reveals the presence of silver peaks and the XRD spectrum confirms the crystalline nature of AgNPs. A Maximum zone of inhibition of 18.04±0.74 was found when the synthesized AgNPs was tested against B. subtilis, and 12.34±0.31 against A. niger when the concentration was AgNPs was maintained at 100 µg/ml.Conclusion: The results of the present study conclude that the AgNPs synthesized using Peltophorum pterocarpum leaf extracts is found to be stable and possesses broad-spectrum antibacterial activity against different tested pathogens

IN VITRO CYTOTOXICITY AND ANTIOXIDANT EVALUATION OF BIOGENIC SYNTHESIZED GOLD NANOPARTICLES FROM MARSILEA QUADRIFOLIA ON LUNG AND OVARIAN CANCER CELLS

Objective: The biogenic gold nanoparticles are considered to be extremely impressive for its wide range of applications in pharmaceutics and therapeutics. The present study was aimed at the biogenic synthesis of gold nanoparticles (AuNPs) from Marsilea quadrifolia aqueous extract and to investigate its antioxidant property and cytotoxic effect on human ovarian teratocarcinoma (PA-1) and lung adenocarcinoma (A549) cell lines.Methods: The biogenic AuNPs was synthesized using an aqueous extract of Marsilea quadrifolia. The synthesized biogenic AuNPs were characterized by ultraviolet (UV) visible spectroscopy, transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction (XRD). The biogenic AuNPs was assessed for its stability over a period of time and antioxidant activity. The cytotoxicity of biogenic AuNPs against PA-1 and A549 cell lines was studied using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.Results: The synthesized biogenic AuNPs showed peculiar ruby red color and a surface plasmon resonance (SPR) peak at 544 nm in the UV-Vis spectrum. The characterization of biogenic AuNPs by TEM, EDX and XRD revealed well dispersed spherical particles ranging from 10-40 nm and the presence of elemental gold and its crystalline nature, respectively. The AuNPs showed good stability and the scavenging activity at 50 μg/ml. The in vitro cytotoxicity of biogenic AuNPs against PA-1 and A549 cell lines recorded half maximal inhibitory concentration (IC50) of 45.88 μg/ml and 52.015 μg/ml, respectively.Conclusion: The biogenic AuNPs demonstrated superior antioxidant and antiproliferative activities against cancer cell lines

ANTIOXIDANT, ANTIBACTERIAL, AND ANTICANCER ACTIVITY FROM MARINE RED ALGAE GRACILARIA EDULIS.

Objective: The marine seaweed Gracilaria edulis was collected from Rameshwaram Mandapam coast. The main objective of G. edulis was to check about the antioxidant, antibacterial, and anticancer activity. The potential use of seaweeds is to prevent colon cancer and leukemia. The crude extract of antioxidant activity was done in methanol and aqueous extract in various concentrations using DPPH assay. The antibacterial activity was analyzed in methanol extract. The antibacterial activity was tested in Gram-positive bacteria (Staphylococcus aureus) and Gram-negative (Pseudomonas) bacteria with various concentration. The anticancer activity was tested against using the breast cancer cell line (MDA-MB231) Methods: The antibacterial activity was checked by crude methanol extract using Gram-positive bacteria (S. aureus) and Gram-negative bacteria (Pseudomonas) with different concentrations. The antioxidant activity was determined using DPPH radical scavenging assay in various concentrations. The anticancer activity was done using 3-(4, 5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay against breast cancer cell line (MDA-MB231). Results: The antioxidant activity of marine red algae was checked using the stable DPPH radical scavenging assay. The antibacterial activity was analyzed and shows the activity of two different bacteria strain against methanol extract. The anticancer activity was done against breast cancer cell line using MTT assay. Conclusion: Thus, the result shows that red algae G. edulis has good biological activity, and further it can be carried out in pharmaceutical, food preservatives, and cosmetic purpose

Assessment of ambient air quality in Chidambaram a south Indian town

Worldwide preliminary studies in large number are advocated to create data base, to identify potential cities / towns that warrant “continuous ambient air quality monitoring and control mechanism” and to evolve priorities for clean air target. The results reported pertain to an eight hour random preliminary air sampling exercise carried out at each of the eight select locations in Chidambaram, a southern semi urban settlement in India. Criteria pollutants SPM, CO, SO2 and NO2 measured are found to have either crossed or on the verge of crossing the limits, necessitating the immediate installation of a continuous monitoring and control mechanism. While transport related emissions are the major sources of air contamination, increasing civil construction activities also contribute to particulates. The exponential rise in volume of vehicles, disadvantageous traffic flow pattern, differing driving cycle pattern and human interceptions deserve due attention. It is concluded that Chidambaram town is a strong case for continuous monitoring of ambient air quality due to alarming and increasing level of pollutants

IN VITRO CYTOTOXICITY OF BIOSYNTHESIZED GOLD NANOPARTICLES FROM SHELLS OF PISTACIA VERA L

Objective: To synthesize the gold nanoparticles by a biological method using the extract obtained from the shells of Pistacia vera (P. vera) and to study its effective role in the anticancer activity.Methods: The synthesis of gold nanoparticles using the extract obtained from the shells of Pistacia vera was confirmed by the color change and substantiating the same using ultraviolet (UV) visible spectroscopy. The size and the shape of the particles were studied using field emission scanning electron microscopy (FESEM). The stability of the nanoparticles was assessed by using the UV visible spectroscopy and Fourier-transform infrared spectroscopy (FTIR). The anticancer activity of the gold nanoparticles on the cancer cell lines was studied on PA1 ovarian cancer cell lines using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Nature of cell death was analyzed using the fluorescence microscopy.Results: The ruby red color confirmed the formation of gold nanoparticles and it was substantiated by the absorption peak at 543.2 nm in the UV visible spectroscopy. The gold nanoparticles synthesized from the Pistacia vera shell showed the spherical shape and were in the size of around 10-40 nm when analyzed with FESEM. The different functional groups were indicated in the FTIR spectra which were consisting of phenol, alcohol, alkenes and aromatics.Conclusion: The synthesis of the gold nanoparticle using the extract obtained from the shells of Pistacia vera has effective anticancer activity

Epidemiology of Untreated Psychoses in 3 Diverse Settings in the Global South: The International Research Program on Psychotic Disorders in Diverse Settings (INTREPID II).

IMPORTANCE: Less than 10% of research on psychotic disorders has been conducted in settings in the Global South, which refers broadly to the regions of Latin America, Asia, Africa, and Oceania. There is a lack of basic epidemiological data on the distribution of and risks for psychoses that can inform the development of services in many parts of the world. OBJECTIVE: To compare demographic and clinical profiles of cohorts of cases and rates of untreated psychoses (proxy for incidence) across and within 3 economically and socially diverse settings in the Global South. Two hypotheses were tested: (1) demographic and clinical profiles of cases with an untreated psychotic disorder vary across setting and (2) rates of untreated psychotic disorders vary across and within setting by clinical and demographic group. DESIGN, SETTING, AND PARTICIPANTS: The International Research Program on Psychotic Disorders in Diverse Settings (INTREPID II) comprises incidence, case-control, and cohort studies of untreated psychoses in catchment areas in 3 countries in the Global South: Kancheepuram District, India; Ibadan, Nigeria; and northern Trinidad. Participants were individuals with an untreated psychotic disorder. This incidence study was conducted from May 1, 2018, to July 31, 2020. In each setting, comprehensive systems were implemented to identify and assess all individuals with an untreated psychosis during a 2-year period. Data were analyzed from January 1 to May 1, 2022. MAIN OUTCOMES AND MEASURES: The presence of an untreated psychotic disorder, assessed using the Schedules for Clinical Assessment in Neuropsychiatry, which incorporate the Present State Examination. RESULTS: Identified were a total of 1038 cases, including 64 through leakage studies (Kancheepuram: 268; median [IQR] age, 42 [33-50] years; 154 women [57.5%]; 114 men [42.5%]; Ibadan: 196; median [IQR] age, 34 [26-41] years; 93 women [47.4%]; 103 men [52.6%]; Trinidad: 574; median [IQR] age, 30 [23-40] years; 235 women [40.9%]; 339 men [59.1%]). Marked variations were found across and within settings in the sex, age, and clinical profiles of cases (eg, lower percentage of men, older age at onset, longer duration of psychosis, and lower percentage of affective psychosis in Kancheepuram compared with Ibadan and Trinidad) and in rates of untreated psychosis. Age- and sex-standardized rates of untreated psychoses were approximately 3 times higher in Trinidad (59.1/100 000 person-years; 95% CI, 54.2-64.0) compared with Kancheepuram (20.7/100 000 person-years; 95% CI, 18.2-23.2) and Ibadan (14.4/100 000 person-years; 95% CI, 12.3-16.5). In Trinidad, rates were approximately 2 times higher in the African Trinidadian population (85.4/100 000 person-years; 95% CI, 76.0-94.9) compared with the Indian Trinidadian (43.9/100 000 person-years; 95% CI, 35.7-52.2) and mixed populations (50.7/100 000 person-years; 95% CI, 42.0-59.5). CONCLUSIONS AND RELEVANCE: This analysis adds to research that suggests that core aspects of psychosis vary by historic, economic, and social context, with far-reaching implications for understanding and treatment of psychoses globally

ASSESSMENT OF AMBIENT AIR QUALITY INDEX FOR CHIDAMBARAM TOWN IN TAMIL NADU, INDIA

This paper examines the significant differences in seasonal variations of air pollutant concentrations in urban, industrial, commercial and agricultural areas of Chidambaram. Suspended particulate matter (SPM), sulphur dioxide (SO2) and oxides of nitrogen (NOx) were collected over eight sites in Chidambaram. The present study deals with the effect of industrialization, urbanization and automobile emission on ambient air quality in Chidambaram. Meteorological parameters like temperature, relative humidity, wind speed and rainfall were also recorded simultaneously during the sampling period. Eight different select pollution prone locations were intentionally identified and 8 hour samplings were carried out during January to December 2008.Monthly and seasonal variation of these pollutants have been observed and recorded. The annual average and range values have also been calculated. It has been observed that the concentrations of the pollutants are high in winter in comparison to the summer or the monsoon seasons. In the present study, it was noticed that the SPM and NOX levels at all selected sites exceeds the prescribed limits as stipulated by the Central Pollution Control Board (CPCB) New Delhi, India. This study reports the analysis of the ambient air in Chidambaram employing air quality index (AQI). The 8-hourly average concentrations of three major criteria pollutants, viz. Suspended particulate matter (SPM),  Sulphur Dioxide (SO2), and Nitrogen Dioxide (NO2) for the year 2008 at eight different locations in Chidambaram have been considered for this analysis

Biosynthesis characterization of silver nanoparticles using Cassia roxburghii DC. aqueous extract, and coated on cotton cloth for effective antibacterial activity

Pannerselvam Balashanmugam, Pudupalayam Thangavelu Kalaichelvan Centre for Advanced Studies in Botany, University of Madras, Chennai, India Abstract: The present study reports the green synthesis of silver nanoparticles (AgNPs) from silver precursor using a plant biomaterial, Cassia roxburghii DC., aqueous extract. The AgNPs were synthesized from the shade-dried leaf extract and assessed for their stability; they elucidated characteristics under UV–visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, and energy dispersive X-ray spectroscopy. The synthesized AgNPs exhibited a maximum absorption at 430 nm, and the X-ray diffraction patterns showed that they were crystal in nature. Fourier transform infrared spectroscopy analysis confirmed the conversion of Ag+ ions to AgNPs due to the reduction by capping material of plant extract. The HR-TEM analysis revealed that they are spherical ranging from 10 nm to 30 nm. The spot EDAX analysis showed the presence of silver atoms. In addition, AgNPs were evaluated for their antibacterial activity against six different pathogenic bacteria: three Gram-positive bacteria, Bacillus subtilis, Staphylococcus aureus, and Micrococcus luteus, and three Gram-negative bacteria, Pseudomonas aeruginosa, Escherichia coli, and Enterobacter aerogenes. They were highly sensitive to AgNPs, whereas less sensitive to AgNO3. Furthermore, the green synthesized AgNPs were immobilized on cotton fabrics and screened for antibacterial activity. The immobilized AgNPs on cotton cloth showed high antibacterial activity. Therefore, they could be a feasible alternative source in treating wounds or may help in replacing pharmaceutical band-aids. Keywords: bioreduction, stability, immobilization, cotton cloth, minimum inhibitory concentratio

STUDY OF THERMAL BEHAVIOUR ON TITANIUM ALLOYS (TI-6AL-4V)

Titanium is recognized for its strategic importance as a unique lightweight, high strength alloyed structurally efficient metal for critical, high-performance aircraft, such as jet engine and airframe components. Titanium is called as the "space age metal" and is recognized for its high strength-to-weight ratio. Today, titanium alloys are common, readily available engineered metals that compete directly with stainless steel and Specialty steels, copper alloys, nickel based alloys and composites. Titanium alloys are needed to be heat treated in order to reduce residual stress developed during fabrication and to increase the strength. Titanium (Ti-6Al-4V) alloy is an alpha, beta alloy which is solution treated at a temperature of 950 ºC to attain beta phase. This beta phase is maintained by quenching and subsequent aging to increase strength. Thermal cycling process was carried out for Ti-6Al-4V specimens using forced air cooling. Heat treated titanium alloy specimen was used to carry out various tests before and after thermal cycling, The test, like tensile properties, co-efficient of thermal expansion, Microstructure, Compression test, Vickers Hardness was examined by the following test. Coefficient of Thermal expansion was measured using Dilatometer. Tensile test was carried out at room temperature using an Instron type machine. Vickers's hardness measurement was done on the same specimen as used for the microstructural observation from near the surface to the inside specimen. Compression test was carried out at room temperature using an Instron type machine. Ti‐6Al‐4V alloy is a workhorse of titanium industry; it accounts for about 60 percent of the total titanium alloy production. The high cost of titanium makes net shape manufacturing routes very attractive. Casting is a near net shape manufacturing route that offers significant cost advantages over forgings or complicated machined parts