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— This research utilizes an attention mechanism to enhance the efficacy of context-driven question-answering (QA) in chatbot technology. To produce more accurate responses to user queries, we used the ALBERT-base-v2-squad_v2 model that has been improved on the Stanford Question Answering Dataset (SQuAD) v2. In order to offer pertinent replies, the model needs to concentrate on key words or phrases in the given context, which is assisted by the attention mechanism. Our tests revealed that the suggested strategy performed better than conventional QA models without an attention mechanism and had a higher accuracy rate. These findings can be extended to numerous chatbot applications and show how attention mechanisms improve context-based quality assurance in chatbots.

In the present period the preface of ultramodern technological gadgets has captured the attention of global population. The reliance of people on these technological Gadgets and services handed by these has reached at similar position that, without these, they can’t suppose a step forward in the direction of their growth. The use of electronic Gadgets, especially mobile phones among youth, has been a growing global concern. The enervating health effect of inordinate operation of Gadgets has been well established. There is an array of health issues like headache, nausea, ophthalmological problems and cerebral issues associated with contrivance use of gadgets. The study conducted in Sarada Vilas Educational institutions included 150 participants conforming of 96 females and 54males. Data was collected using a semi-structured questionnaire through Google forms from council scholars. This study is generally aimed at relating the extent of dependence affecting mental health (quality of sleep, depression, anxiety and stress) among council scholars. The outgrowth of this study is anticipated to contribute to various parties especially teenagers and parents in relating the rudiments that can lead to internal health and also serves as a companion in helping this group reduce their reliance on this contrivance. By understanding the goods of contrivance use, it would be possible to produce interventions and suggest ways to manage the inordinate use of gadgets.

A 27 year old male was scheduled to undergo open reduction and internal xation (ORIF) with PHILOS plate for left shoulder proximal humerus fracture. Aneasthesia was induced with atracurium. Patient developed tachycardia and fall in saturation within 20 minutes, which was managed conservatively and procedure was continued. During intraoperative period patient developed muscle rigidity on left hand along with hypotension and hyperthermia, which confused the surgeon and anesthesiologist whether it is attributed to the drug or some other genetic factors. Patient underwent rst episode of cardiac arrest after 45 minutes induction of general anaesthesia. He was resuscitated but developed second episode of cardiac arrest after a few minutes. Patient was shifted to MICU, all supportive and resuscitation measures were given. Despite all resuscitative measures, patient could not be revived and expired on post op day 2. Later on postmortem report revealed presence of 3,4- methylenedioxymethamphetamine (MDMA) in blood and body uids. There has only been one evidence of atracurium induced malignant hyperthermia reported before, but the probablity of devoloping hyperthermia in this case was probably high. The aim of this study was to investigate whether MDMAor Atracurium is a trigger of malignant hyperthermia in this patient

Congenital adrenal hyperplasia (CAH) comprises a family of autosomal recessive disorder and it will disrupt adrenal steroidogenesis. The most common form of CAH is due to 21-hydroxylase deficiency associated with mutations in the cyp21a2 gene which is located at chromosome 6p21. The clinical features associated with this adrenal steroidogenesis represent a clinical spectrum reflecting to the consequences of the specific mutations. Treatment goals include normal linear growth velocity and “on-time” puberty in affected children. [1] Infection with Varicella zoster virus (vzv) causes chickenpox means Varicella that can be severe in immunocompromised individuals, infants and adults. The primary infection is followed by latency in ganglionic neurons. During this time, no virus particles will produce and no obvious neuronal damage occurs. Reactivation of virus leads to virus replication, which will causes zoster (shingles) in tissues innervated by the involved neurons, inflammation and cell death [2]. Potential complications of this infection are involved in the central nervous system causing encephalitis. An increased risk of this complication is associated with the immunocompromised patient. [3] Keywords: congenital adrenal hyperplasia, varicella zoster infection, varicella encephalopathy, cerebellitis.

Objectives Neera, non-fermented coconut inflorescence sap (NFCIS) and its fermented form, toddy (FCIS) are the two well-known traditional drinks in South India. Both the saps show high rejuvenation effect and NFCIS is used for the curing of bronchial suffocation, anemia, tuberculosis and piles in traditional medicine. But, a few scientific studies have been reported on their health benefits so far. Presently, the antioxidant effect of both non-fermented (NFCIS) and fermented form (FCIS) of coconut inflorescence were analyzed in experimental animals. Methods The free radical scavenging property of FCIS and NFCIS was analyzed in vitro. The effect of these saps on mitigating sodium fluoride (NaF) deteriorated redox status was evaluated in mice. Results NFCIS exhibited high antioxidant activity than its fermented form. NFCIS reduces metal ions and scavenge hydroxyl and DPPH radicals with IC50 values 6.5 ± 1.9 and 44 ± 3.14 µL/mL, respectively. Supplementation of NFCIS for 14 days increased SOD, CAT and GPx activities and GSH level in liver by 51.67, 52, 27.88 and 35.77%, respectively against NaF induced decline with a concomitant decrease in lipid peroxidation to 40.76%. Saps rich in minerals indicate pharmaceutical and nutritional value. Conclusion The study revealed the antioxidant efficacy of non-alcoholic natural drink, Neera and recommends an alternative for synthetic carbonated soft drinks. The regular consumption of Neera may protect the body from various chronic diseases especially where the oxidative stress played as a key role.

Background: Patients with malignancy undergoing chemotherapy, surgery, and radiation therapy experience a variety of symptoms that affect their quality of life (QOL). This necessitate the assessment of QOL on their subjective evidence that can be utilized in diagnosis, predicting prognosis, patient monitoring and clinical decision making. This information will help health care professionals to design interventions and recommend the appropriate treatment, thereby improving the QoL of patients. In this study we aim to assess the QoL of patients receiving adjuvant and neo-adjuvant therapy for Lung, Breast, and Colorectal cancer, in addition to making correlations according to type of treatment and disease stage. Methods: A prospective observational study was carried out in the radiation oncology department from March 2021 to September 2021 in Krishna Rajendra Hospital, Mysuru, India. We used the European Organization for Research and Treatment of Cancer quality of questionnaire [EORTC QLQ – C30] Version 3.0 to assess the QoL of patients. Patients were interviewed twice, when they came to have their chemotherapy regardless of the cycle number and during the next visit. Results: The number of patients enrolled in the study were 107. Most of participants were female 83%. About 73.8% diagnosed with breast cancer. In patients treated with adjuvant versus neo-adjuvant treatment, the functional scores and global health status scores were statistically significant p=0.038 and p=0.010 respectively with mean scores 63.54 in favour of adjuvant therapy. These results represent a better QoL in patients received adjuvant versus neo-adjuvant therapy. The mean values of global health status score in patients diagnosed with lung cancer during the two assessments (47.72, 51.51) were lesser than those in patients diagnosed with breast cancer (63.71,63.50) and colorectal cancer (58.82,58.82), indicating patients with lung cancer had poor QoL compared to breast and colorectal cancer patients. Conclusion: Patients received adjuvant therapy had better QoL compared to those received neo-adjuvant therapy. The QoL in lung cancer patients were majorly affected as compared to QOL in breast and colorectal cancer patients. there is a strong correlation between the type of treatment and disease stage.

BACKGROUND Sepsis is responsible for 30-50% of the total neonatal deaths in developing countries and is considered the commonest cause of neonatal mortality. Neonatal sepsis has wide range of presentations with number of predisposing factors. Our study aims at detecting the risk factors of neonatal sepsis and to describe the clinical features and laboratory profile of neonates started on intravenous antibiotics for neonatal sepsis. METHODS 120 neonates (60 cases and 60 controls) admitted in the department of child health were enrolled in the present case control study and all cases were subjected to diagnostic evaluation and data was collected using restructured case record forms which included perinatal history, signs and symptoms associated with sepsis and laboratory investigations. Institutional Ethics Committee approved the study and written informed consent was obtained from all consenting mothers. Parameters are expressed as mean (SD) and as proportions. RESULTS 52.5% neonates and 55% cases were males. 25% of cases were preterm deliveries and 21.7% cases were small for gestational age. Premature rupture of membranes (PROM), maternal urinary tract infections (UTI), and gestational diabetes mellitus (GDM) were seen in 16.7%, 10% and 28.3% cases. Hypothermia was a symptom of sepsis in 28.3% while fever was a symptom in 21.7% cases. CRP elevation and toxic granulations were seen in 75% and 33.3% cases. 6.7% cases had a positive blood culture. CONCLUSIONS Manifestations of neonatal sepsis are non-specific. A high index of suspicion with or without laboratory evidences of sepsis is the key for early diagnosis. Prompt institution of antibiotic therapy and supportive care will save most of the cases of neonatal sepsis.

BACKGROUND The prevalence of heart murmur during the first week of birth varies from 0.6-44.7% and congenital heart disease (CHD) varies from 4-50 per 1000 live births in different studies. Though most are clinically insignificant, few are associated with various structural abnormalities. Our study was conducted to determine the prevalence of cardiac murmurs and congenital heart disease in neonates of rural Kerala. METHODS 1000 consecutive live born neonates were enrolled in our descriptive study during a period of 10 months conducted at Sree Gokulam Medical College & Research Foundation Venjaramoodu. Neonates were screened after 24 hours of birth by residents using 3M® Littman™ paediatric stethoscope and all detected murmurs were referred to cardiologist for echocardiography. Study was conducted after approval from Institutional Ethics Committee and written informed consent was obtained from all participating mothers. Data was collected in semi structured questionnaire and are expressed as proportions. RESULTS 19 and 14 neonates had audible murmur and CHD with a prevalence of 19 and 14 per 1,000 live births respectively. 85.7% (n=12) of lesions were acyanotic lesions and 14.3% (n=2) were cyanotic. Congenital heart diseases encountered were atrial septal defect (26.3%), ventricular septal defect (26.3%), patent ductus arteriosus (5.3%), cyanotic heart with multiple lesions (10.5%), tetralogy of Fallot (5.3%) and hypoplastic left heart syndrome (5.3%). CONCLUSIONS Structural lesion was seen in 73.7 cardiac murmurs. Atrial septal defect and ventricular septal defects were the most common structural lesions.

Background: In sick neonates, we are posed to treat suspected or proven infection. However, the vast majority of newborn babies who are given antibiotics do not have any infection. Objective: The objective of this study was to optimize the use of empirical antibiotic therapy in late preterms who are asymptomatic with maternal risk and symptomatic neonates without maternal risk for early-onset sepsis (EOS) and to estimate the rate of risk increase in onset of symptoms in neonates exposed to maternal risk factor for EOS. Methods: In this descriptive study, late preterm neonates (34+0–36+6 weeks) who are asymptomatic at birth with and without maternal risk factor for EOS at birth were subjected to clinical assessment of sensorium, temperature, oxygenation status, perfusion, and skin color, starting after 1 h of initial stabilization till discharge from hospital. Sepsis screen (C-reactive protein and absolute neutrophil count) was obtained at 24 h and 48 h of age from these asymptomatic late preterms. Results: A total of 135 late preterm neonates (34+0–36+6 weeks) recruited during the study period were included for analysis. The presence of maternal risk factor for EOS has shown no statistical significance in relation to the presence of symptoms at birth odds ratio 0.66, 95% confident interval (0.24–1.8) p=0.42. Conclusion: In our study, as maternal risk factor for sepsis has shown no statistical significance in relation to the presence of symptoms at birth, antibiotic use can be restricted to only those babies who have clinical worsening over 24–48 h of observation and/or along with supportive evidence of positive sepsis screen and/or blood culture, irrespective of the presence or absence of maternal risk for EOS.

We report a possible instance of hybridization between the Ratufa indica and Ratufa macroura from Western Ghats. The details on the coat of the hybrid individuals, location map where the hybrids where sighted and the conservation challenges have been discussed in the paper.

South Asia is characterized by large population size, high population growth rate, unprecedented urbanization, and unique challenges posed by ongoing climate change. These challenges pose huge concerns for the food, nutrition, and livelihood security of millions living in the subcontinent. Mitigating climate change impacts on agriculture presents a very complex challenge, owing to the extreme vulnerability of crop production systems to several climate-linked critical inputs. In addition, agricultural systems themselves are responsible for nearly a quarter of greenhouse gas emissions. Hence, adaptation of agricultural systems, as a mainstream response to the risks posed by climate change, is a pragmatic way forward to address the development challenges facing the millions living in the region. Climate-Resilient Agriculture (CRA) aims to promote resilience in agricultural production systems and the dependent communities, to respond effectively to climate change through enhancing of input efficiency, system resilience, crop yield, income diversification, value chain development, and robust institutional and governance arrangements. However, wide-scale adoption of CRA is fraught with several constraints linked to technology access, locality challenges, skill gaps, socioeconomics, institutional capacity, and governance quality. Several gaps have already been reported about documentation, prioritization, and promotion of CRA across diverse agro-ecological landscapes in South Asia. Driven by those concerns, we explored emerging discourses and initiatives on CRA in South Asia to address the following questions: (a) what is the emerging typology of CRA in the region?; (b) what barriers and challenges are affecting wide-scale adoption of CRA?; and (c) what are the strategic areas to focus on? In order to address those questions, we followed a systematic analysis of the recent literature and identified major issues in CRA, prevailing discourses on CRA, and policy positions impacting CRA from selected countries in the region. The chapter also presents a typological framework of the emerging scenario of CRA in the region along with some suggestions to mainstream CRA in the region.

Objectives Neera, nonfermented coconut inflorescence sap (NFCIS) from unopened spadix of Cocos nucifera L., is a well-known traditional beverage. But, scientific reports on its health benefits are limited. NFCIS is reported to exhibits free radical scavenging activity, and its chemical composition is found promising. In the present study, the effect of NFCIS on alleviating cisplatin-induced nephrotoxicity was analyzed in mice. Methods The renal toxicity was induced by cisplatin (16 mg/kg b.wt. ip) in Swiss albino mice. The antioxidant activity of NFCIS was evaluated by nitric oxide radical scavenging assay and phorbol-12-myristate-13-acetate–induced superoxide radical generation in mice peritoneal macrophages. Total polyphenolic content of sap was determined using Folin–Ciocalteu reagent. The phytochemicals present in NFCIS was identified using Fourier transform infrared (FT-IR) spectroscopy. Results NFCIS was found to scavenge nitric oxide (NO) radicals (IC50 = 32 ± 2.47 μL/mL) and shown to inhibit superoxide (SO) generation (53.5 ± 2.1%) in macrophages. High polyphenolic content (193 µg gallic acid/mL) was determined in the sap. The FT-IR spectrum of NFCIS revealed the presence of several phytochemicals indicate its pharmaceutical and nutritional value. Cisplatin-induced hike in urea, creatinine and lipid peroxidation was significantly decreased to 65.16, 87.74 and 53.41% by NFCIS, respectively. Hb (42.37%) and total count (72.81%) were also found to be increased. Additionally, the activity of antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase and reduced glutathione was enhanced to 53.06, 40, 52.22 and 38.49%, respectively. Conclusions Results indicate that NFCIS effectively alleviates cisplatin-mediated renal toxicity by its antioxidant activity.

Respiratory distress syndrome, although it is common in extreme preterm infants, early and effective management will aid in better outcome. Preterm also comes with multiple co- morbidities which has to be considered and stepwise treatment is utmost important in tackling them. Here, we report a case of an extreme preterm baby who experienced respiratory distress syndrome with early onset sepsis along with necrotizing enterocolitis. Early diagnosis and management helped in the discharge of the infant in stable condition.

Autoimmune encephalitis is an immune-mediated syndrome with sub-acute to chronic presentations, such as memory impairment, altered sensorium, behavioral abnormality, psychosis, and seizures. Treatment as such must not be procrastinated due to pending laboratory workup, as early recognition and initiation of therapy prevents long term neurological sequelae. This is a case report of an 11-year-old male who presented with neuropsychiatric symptoms, altered sensorium and high-grade fever which evolved into refractory status epilepticus and autonomic dysfunction. While his MRI had positive findings of encephalitis, he tested negative for infectious diseases and antibody panels.

Background: The objectives of the study were to assess the outcomes of clinical pharmacist intervention in solving drug related problems in pediatric patients and to identify the drug related problems in accordance with the causes observed.Methods: It was a prospective observational study done over a period of six months (October 2019 to March 2020) at Apollo children’s hospital in Chennai.Results: Total of 480 subjects were enrolled into the study, out of which 248 were male children and 232 were female children. The patients were divided into 4 age groups. In this study 60.41% pediatric patients were prescribed with less than 5 drugs 290 (60.41%). Drug related problems which were identified during the study was classified according to Pharmaceutical Care Network Europe (PCNE) and drug-related problem (DRP) classification (v9.00). The most frequent DRP was drug choice problem 37 (33.33%). The total number of caused drug related problems was 73 and same number of interventions was given by clinical pharmacist. The most frequent cause of drug related problems was identified as dose selection 31 (42.46%). Outcomes of interventions revealed that 70 (95.89%) problems were solved overall.Conclusions: In this study, clinical pharmacist’s level of involvement has shown interesting results. Moreover, they play an essential role in improving patient safety and outcome, reducing cost and providing quality of care for ill patients.

Background:Pediatric infectious disease was mainly caused by bacteria, viruses, fungi and parasites. Antibiotics are strong and effective medicines, used to treat various infections. When antibiotics were first introduced, they were strong and efficient treatments for different infectious diseases. Objectives:The objectives were to evaluate prescription pattern of antibiotics in infectious diseases and to identify the common routes of administration and also to identify the drug interactions. Methodology:A prospective, hospital based study was conducted for a period of six months on 120 Pediatric subjects suffering from infectious diseases. A written informed assent was obtained from all the subject representatives before inclusion in the study. Patient demographics, laboratory data and treatment chart were reviewed. The study results were analyzed by descriptive statistical analysis. Results:A total of 120 subjects aged up to 12 years data were collected. Out of 120 subjects, maximum number of subjects was admitted due to acute gastroenteritis. The common route of administration was parenteral in that 75% intravenous and 2.1% intramuscular. From this study we found that the most commonly interacting drugs were ceftriaxone +Amikacin (7.1%). Conclusion:The study reveals that the most common infectious disease was acute gastroenteritis and the common antibiotic prescribed was Cephalosporin class. The common route of administration was Parenteral and the most common drug interactions were found between ceftriaxone + Amikacin. &nbsp

In our quest for materials with specific applications, a theoretical study plays an important role in predicting the properties of compounds. Heusler alloys or compounds are the most studied in this context. More recently, a lot of quaternary Heusler compounds are investigated for potential applications in fields like Spintronics. We report here our preliminary study of the alloys ScMnFeSn and ScFeCoAl, using the ab-initio linear muffin-tin orbital method within the atomic sphere approximation (LMTO-ASA). The alloy ScMnFeSn shows perfect half-metallicity, namely, one of the spins shows a metallic behaviour and the other spin shows semi-conducting behaviour. Such materials find application in devices such as the spin-transfer torque random access memory (STT-MRAM). In addition, the alloy ScMnFeSn is found to have an integral magnetic moment of 4 µB, as predicted by the Slater-Pauling rule. The alloy ScFeCoAl does not show half-metallicity.In our quest for materials with specific applications, a theoretical study plays an important role in predicting the properties of compounds. Heusler alloys or compounds are the most studied in this context. More recently, a lot of quaternary Heusler compounds are investigated for potential applications in fields like Spintronics. We report here our preliminary study of the alloys ScMnFeSn and ScFeCoAl, using the ab-initio linear muffin-tin orbital method within the atomic sphere approximation (LMTO-ASA). The alloy ScMnFeSn shows perfect half-metallicity, namely, one of the spins shows a metallic behaviour and the other spin shows semi-conducting behaviour. Such materials find application in devices such as the spin-transfer torque random access memory (STT-MRAM). In addition, the alloy ScMnFeSn is found to have an integral magnetic moment of 4 µB, as predicted by the Slater-Pauling rule. The alloy ScFeCoAl does not show half-metallicity.

The key to provide microbiologically safe drinking-water lies in understanding the various mechanisms by which water gets contaminated. This study assessed the risk of contamination and microbiological and chemical quality of water from protected dug wells in five selected Panchayats in Kollam district, Kerala state, southern India. Sanitary inspection was conducted for 70 protected dug wells using World Health Organization established procedures for risk of contamination scoring. Microbiological and chemical analysis of water samples was done. The areas with higher incidence of hepatitis A had a higher proportion of wells with high risk of contamination scores (p = 0.006). High risk of contamination scores for wells were associated with higher incidence of fecal pollution (odds ratio 11.80; 95% confidence interval 1.87–74.86). The study highlighted the need to make the wells safe in this area, for control of waterborne diseases.

Hepatitis B virus (HBV) infections have been consistently reported over the last few years from the two wards of Thrikkaruva, Kollam district, Kerala, southern India. This study was conducted to determine the risk factors associated with HBV transmission in Thrikkaruva.This was a community based, case-control study, enrolling HBsAg positive cases diagnosed since January 2010. Controls were age (+5 years) and sex matched neighbourhood individuals. Data was collected using a questionnaire and all subjects were investigated for HBsAg, anti-HBs and anti-HBc. Local healthcare institutions serving the community were surveyed for infection control practices. Statistical analysis for HBV associated factors was carried out.A total of 49 cases and 49 controls were included in the final analysis. Logistic regression revealed close personal contact with of a case of hepatitis B (adjusted OR: 3.09, 95% CI: 1.13-9.40) as a significant risk factor in the community. Qualitative examination of infection control practices at private clinics, barber shops and dental clinics revealed conditions conducive for HBV transmission in the community.Our study reveals active horizontal person-to-person HBV transmission in the village. Comprehensive action including vaccination of all susceptible contacts, promotion of infection control at health care institutions, and raising public awareness are recommended in this region.

This paper addresses the fracture properties of commercially cold-drawn (53%) MP35N (35% Co, 35% Ni, 20% Cr, and 10% Mo) in both the cold-worked and the cold-worked and aged conditions. MP35N is a superalloy that exhibits a remarkable combination of high strength (about 2 GPa) and high fracture toughness (about 100 MPa m ). The fracture toughness of MP35N was investigated systematically, with particular attention to the influence of the post deformation aging heat treatment, the sample thickness, the orientation of crack plane and the direction of crack propagation with respect to the drawing direction in the sample. These measurements yielded the following important results: (1) The plane strain fracture toughness of the commercially cold-drawn MP35N is about 120 MPa m , and is about 110 MPa m in the cold-drawn and aged condition. (2) The plane stress fracture toughness values for the cold-drawn MP35N were significantly lower than the corresponding values for the cold-drawn and aged material, in spite of the fact that the later had a higher strength value. (3) The direction of the crack propagation did influence the fracture toughness, reducing its value significantly in T–L direction, as compared with values in T–T and L–T directions.

The multiphase alloy MP35N (35% Ni, 35% Co, 10% Mo, 20% Cr) is a high strength, high toughness alloy of choice for several safety-critical applications in aerospace, oil drilling, and biomedical industries. Several previous attempts in literature to measure the plane strain fracture toughness of commercially drawn MP35N did not produce reliable values since they violated one or more of the criteria stipulated by ASTM standards for a valid measurement of K Ic . In most cases, the requirements for plane strain and small scale yielding conditions were not met, since the commercially drawn material was available only with limited cross-sectional dimensions. In this investigation specially designed specimens (modified compact tension (CT) specimens) have been used to measure the plane strain fracture toughness of MP35N in both the unaged and the aged conditions. The K Ic of the commercially drawn (53% reduction level) MP35N was measured to be 126 MPa√m, while that of the commercially drawn and aged MP35N was measured to be 98 MPa√m. Both these measurements satisfied all the required criteria stipulated by ASTM standards for valid measurements of K Ic . The new procedure used in this study has been verified by the measuring of fracture toughness of Al alloy, using both the modified specimen, as designed here, and the standard one. The results for plane strain fracture toughness of MP35N alloy have been verified by the standard measurement of J Ic values for both the aged and the unaged alloys. Finally, on a suitably normalized plot, introduced in this paper, the toughness-strength envelop for MP35 is higher than most of structural alloys, but significantly lower than that of the TRIP steels.

A novel microwave coplanar sensor system for detecting contamination in food products such as milk and oil etc., is designed and developed. The developed system is fully non-invasive and non-destructive, which requires the test liquid to be filled into a disposable container. The sensor placed above the liquid filled container is connected to the network analyzer through appropriate RF connectors to measure the scattering coefficients of the test fluid over a designated frequency band. The dielectric properties of the adulterated specimen are determined in terms of the measured scattering data, and these values are compared with the dielectric data of standard samples in order to find the level of contamination.

MP35N (35% Co, 35% Ni, 20% Cr, and 10% Mo) is a superalloy that exhibits a remarkable combination of high strength and high fracture toughness. This alloy derives its strength mainly from two processes — cold work and a subsequent aging heat treatment. This study examines the influence of the amount of cold-work, imposed in the drawing and the rolling processes, and the subsequent aging heat treatment on the strength and ductility (which is also an indicator of toughness) of this alloy. It was found that high levels of cold-work followed by the aging heat treatments resulted in a drastic drop in the ductility of the alloy. This drastic loss of ductility was correlated with appearance of macro-scale shear bands in the samples. The physical origin of these localized shear bands is investigated in this paper. Furthermore, this study established a processing window for MP35N (in cold-drawing and cold-rolling processes) where the aging heat treatment provides the desired increase in the strength without adversely influencing the ductility of the alloy.

Mechanical testing and microscopy techniques were used to investigate the influence of aging on the structure and strengthening of MP35N alloy. It was confirmed that aging the deformed material at 600°C for 4 h provided additional strengthening, here referred to as “secondary hardening”, in addition to the primary strain hardening. The secondary hardening phenomenon was shown to be distinctly different from typical age hardening processes in that it only occurred in material deformed beyond a certain cold work level. At moderate strains, aging caused a shift in the entire stress–strain curve of the annealed material to higher stresses while at high strains, it produced shear localization and limited work softening. The secondary hardening increment was also found to be grain size dependent. The magnitude of the secondary hardening appeared to be controlled by the flow stress in the strain hardened material. A model is proposed to explain the observations and is supported by direct experimental evidence. The model is based on formation of h.c.p. nuclei through the Suzuki mechanism, that is segregation of solute atoms to stacking faults, on aging the strain hardened material. The h.c.p. precipitates appear to thicken only in the presence of high dislocation density produced by prior cold work.

BACKGROUND AND AIM: Hepatitis B virus (HBV) infections have been consistently reported over the last few years from the two wards of Thrikkaruva, Kollam district, Kerala, southern India. This study was conducted to determine the risk factors associated with HBV transmission in Thrikkaruva. METHODS: This was a community based, case-control study, enrolling HBsAg positive cases diagnosed since January 2010. Controls were age (+5 years) and sex matched neighbourhood individuals. Data was collected using a questionnaire and all subjects were investigated for HBsAg, anti-HBs and anti-HBc. Local healthcare institutions serving the community were surveyed for infection control practices. Statistical analysis for HBV associated factors was carried out. RESULTS: A total of 49 cases and 49 controls were included in the final analysis. Logistic regression revealed close personal contact with of a case of hepatitis B (adjusted OR: 3.09, 95% CI: 1.13-9.40) as a significant risk factor in the community. Qualitative examination of infection control practices at private clinics, barber shops and dental clinics revealed conditions conducive for HBV transmission in the community. CONCLUSIONS: Our study reveals active horizontal person-to-person HBV transmission in the village. Comprehensive action including vaccination of all susceptible contacts, promotion of infection control at health care institutions, and raising public awareness are recommended in this region.