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Mohale, H.P.; Jawahar, P.; Jayakumar, N.; Swapnil, N.; Kadam, R.V.; Prakash, P.; Oli, G.A., and Ravikumar, T., 2024. Fishery, biology, and dynamics of Parapenaeopsis maxillipedo (Alcock, 1905) off the SE coast of Tamil Nadu (India). Journal of Coastal Research, 40(4), 779–791. Charlotte (North Carolina), ISSN 0749-0208. The current study was carried out between September 2022 to September 2023 from SE coast of Tamil Nadu for Parapenaeopsis shrimp. This shrimp, estimated to rank third in shrimp production, landed as 2216, 2032, and 1704 kg from Thoothukudi, Mandapam, and Nagapattinam landing centers, respectively. The catch per unit effort was calculated to check the abundance of this species and ranged from 21.83 to 96.41 kg, averaging 46.33% in both years. The total length of males and females was observed in the range of 5.5 to 10.5 cm and 6.5 to 12.5 cm, respectively. Female shrimp attained first maturity at 6.5 cm, whereas male shrimp were 5.5 cm. The gonadosomatic index was calculated and found to be the highest (5.64–5.78) in March and September and the lowest in April and October for both years. The absolute fecundity for P. maxillipedo was recorded and ranged from 38,500 to 1,32,000 ova per female. The highest index of relative importance was observed in October and April for both male (57.04) and female (73.82) shrimp. To estimate von Bertalanffy's growth equation in P. maxillipedo, the asymptotic length and growth coefficient (K) growth parameters were combined for both sexes and analyzedas 13.55 cm and 1.5 y–1, respectively. The total mortality and natural mortality (M) were observed as 3.04 and 2.86 y–1, respectively. Hence, fishing mortality was 0.18 y–1, and the exploitation rate (E) was 0.06. The length at first catch per length (LC/L) and M/K values were calculated using the Y/R model as 0.52 and 1.2 for males and 0.48 and 1.3 for females, respectively. E was observed as 0.06, which was lower than the maximum E of 0.4, which showed that the P. maxillipedo fisheries along the SE coast of Tamil Nadu were at unexploited conditions. [ABSTRACT FROM AUTHOR]

The COVID 19 pandemic has challenged the humankind's livelihood, physical health, mental health, employment, and economy. Lockdowns, quarantines, online teaching, and learning have become new normal. Negativities have been spread across the globe and society by the pandemic. The negative effects caused a confused mindset, fear, anxiety, stress, and other psychological complications amongst the people especially among the Health Care Workers (HCWs), children, elderly people, and Frontline Workers (FLWs). This research work examines the levels of Occupational Stress (OS), and psychological well-being (PWB) of HCWs and police personnel during the pandemic and the relationship between OS and PWB. Further, the study analyzed the role of Positive Psychological Capital (PPC) as a mediator and Emotional Quotient (EQ) as a moderator in the relationship between OS and PWB. Positive Psychological Capital (PPC) characteristics of the respondents such as having faith in one's ability, and performance, willingness to succeed or attain the goals framed, ability to bounce back from the hard times, and their optimism about the future have helped them to tackle the stress caused by the pandemic and to maintain a better state of psychological wellbeing in the fight against the pandemic., Author(s): T. Ravikumar [sup.1] Author Affiliations: (1) grid.440672.3, 0000 0004 1761 0390, School of Business and Management, CHRIST (Deemed University), , Bangalore, Karnataka, India Introduction The COVID 19 has upended [...]

Mohale, H.P.; Jawahar, P.; Jayakumar, N.; Oli, G. Arul; Ravikumar, T., and Bhosle, R., 2024. Ecomorphology of selected penaeid shrimp in the coastal marine waters of Tamil Nadu (southern India). Journal of Coastal Research, 40(2), 303–318. Charlotte (North Carolina), ISSN 0749-0208. This study investigated how shrimp morphology is influenced by the environment by examining the effects of components like temperature, salinity, substrate type, and water currents; it exposed how these variables affect the development and expression of morphological traits in shrimp species by examining patterns of morphological variation within and between species to demonstrate the contributions of natural selection, genetic drift, and phenotypic plasticity to the diversification of shrimp morphology. The prevalence of shrimp species was: Penaeus indicus > Metapenaeus dobsoni > Metapenaeus brevicornis > Penaeus canaliculatus > Penaeus semisulcatus > Penaeus mergiuensis > Penaeus japonicas > Metapenaeus moyebi > Penaeus latisulcatus > Penaeus monodon. The study results showed negative correlations between biochemical oxygen demand and dissolved oxygen and a harmful effect on the morphological characteristics and growth of shrimp species. According to single factor and comprehensive pollution indices, the water bodies in this study were moderately polluted. P. semisulcatus had higher mean values for the ecomorphology parameters, indicating no adverse effects and a positive relationship. P. semisulcatus shrimp were also found to have decadal growth development and survivability. P. mergiuensis had the lowest growth rates. Results indicated detrimental effects and a bad association when evaluating decadal growth, development, and survival for most of the other shrimp species. This study enhances knowledge of the evolutionary processes that have shaped shrimp adaptations over time and highlights the challenges for sustainability of the biodiversity in the coastal marine waters of Tamil Nadu, India. [ABSTRACT FROM AUTHOR]

The present work involves in a novel approach of studying the material characteristics of AZ31 alloy by varying the cooling method in powder metallurgy and particle size of the matrix material. It also has a novel approach of reinforcing AZ31 alloy with quarry dust and providing self oxide coating to the material in a distinct way for corrosion resistance. The alloy is prepared through powder metallurgy with a pressure of 675 MPa, sintered at 540 ºC, with one hour of soaking. The Scanning Electron Microscopy images are taken to analyse the microstructure. Wear and corrosion studies are done to analyse the effect of parameters. Optimisation for wear is also done with Taguchi method. The AZ31 samples reinforced 5, 10 and 15% of quarry dust are prepared and studied for mechanical properties. The material prepared using 75–150 micron range, cooled in still air cooling and with 5% reinforcement has shown higher values of compressive strength and microhardness. The alloy provided with self-oxide coating has shown higher resistance to corrosion than that of uncoated alloy and the composite. [ABSTRACT FROM AUTHOR]

As there are job opportunities worldwide, the graduates who are being produced in large numbers from various backgrounds are constantly trying to get them. Moreover, the management of graduate colleges gives proper training to the students to get those opportunities. Every student has their skills, unique creative outlook, studying, and good academic skills that help them get placed in various companies and also have a chance to get reputed positions, but most of the graduates are still failing to get the opportunity because they cannot find what skills to acquire. For this reason, in this paper, we gathered information from students who have finished their courses at different colleges. Collected information by communication and asked them about their academics, performance, families, skills, personal information, habits, etc., and what prevented them from taking the opportunity. Then, we made a dataset with all the factors that affected a student's career and used that to create a model with synthetic data. Student Placement Prediction can also benefit colleges and universities by providing valuable observations of student career outcomes. By understanding the factors influencing student job placement, colleges can conduct services and programs to help their students be better prepared for their careers. Accuracy and precision were used to evaluate the eXtreme Gradient Boost (XGBoost) machine learning model's performance compared to standard classification techniques. According to the results, the proposed algorithm is vastly superior to the alternatives. [ABSTRACT FROM AUTHOR]

Trimethylamine (TMA) is highly toxic and can have lethal effects on living organisms. Detecting the presence of TMA in air is very important because, if the TMA level exceeds the OSHA (Occupational Safety and Health Administration) limit, it may harm the environment and endanger human life. Doping is an appropriate flexible way to change the electrical structures of metal oxide semiconductors (MOSs) and improve their ability to detect toxic gases. In this work, Mn-doped zinc ferrite thin film nanorods with agglomerated morphology were fabricated by a spray pyrolysis technique. For the first time, a comprehensive investigation was done on the gas sensing capabilities of Mn-doped ZnFe 2 O 4 thin films. The findings showed that ZFM1 had the best gas sensing characteristics, with high sensitivity ( S = 6.24), good selectivity, and quick recovery, towards 10 ppm TMA at ambient temperature. The alternate Mn-ZF sites are responsible for the rapid recovery because they can significantly increase the concentration of oxygen vacancies in the ZF crystal. 0.1 Mn doped ZnFe 2 O 4 (ZFM1) thin film exhibits greatly enhanced gas sensing properties towards TMA, because of its high surface-to-volume ratio and rough surface with a small nanorod structure. The sensor's response to 10 ppm TMA was measured 13 weeks later for stability testing. The stability test results show that the coated ZFM1 film works well as a TMA gas sensor. This work shows that ZF thin films are effective in detecting TMA in the atmosphere.

Desires of materials with lesser weight made wide spread use of alloys based on magnesium in automobiles and aerospace applications in the view of overcoming lower strength of these materials when compared to aluminium, these materials are added with some hard materials like ceramics, metal oxides or natural remaining as a reinforcing phase with a proof for improvement in properties. In the present work AZ31 alloy is strengthened by adding Coconut Shell Ash particles (CSAp) by means of powder metallurgy and the examinations like microstructure, micro hardness, compressive strength and wear are conducted. The ash particles content as reinforcement has not imparted larger variation in the strength and hardness, the wear resistance is increased with the addition of ash particles and the addition of CSAp exceeding 3% leads to crack. [ABSTRACT FROM AUTHOR]

Magnesium based alloys are some of the widely used light weight metals in vehicles and aerospace industries, but these materials are having low strength to weight ratio when compared to aluminium. To enhance their strength to weight ratio, some ceramic materials like carbides and oxides of metals are added as reinforcements. In this work, AZ31 magnesium alloy is reinforced with 1%, 2% and 3% of Groundnut Shell Ash particles (GSAp) through powder metallurgy. Micro hardness and compressive strength are studied and the microstructural analysis is also done. The addition of ash particles as reinforcement has not shown much variation in the strength and hardness. The addition of ash particles of more than 3% leads to crack. The addition of ash particles increases the rate of corrosion. [ABSTRACT FROM AUTHOR]