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Hybrid photovoltaic–thermal (hPVT) collectors are devices that allow the conversion of sun energy into useful thermal and electrical energy simultaneously. The power obtained from the photovoltaic (PV) module introduces random fluctuations into the system. While obtaining the data for PV power output in advance and for reducing the impact of random fluctuations, exact day-ahead PV power prediction is crucial. Machine learning algorithms have been proven an effective tool in PV technology for day-ahead prediction of PV-power output. This research employs the Gaussian process regression method using the Matlab environment for forecasting the hPVT collector's performance operating with pure water and Fe/water nanofluid. A one-year historical data pertaining to solar irradiance as well as ambient temperature for Roorkee (29.8543 °N, 77.8880 °E), India location has been used to validate the proposed model. This data is utilized for day-ahead forecasting of solar irradiance and ambient temperature. The outcome elucidates that as the mass-flow rate increases, the thermo-electric performance of the hPVT collector enhances. Raising the mass-flow rate of Fe/water nanofluid from 0.01 to 0.1 kg/s, the cell temperature decreases by 9.35 °C and 9.47 °C, respectively, for the actual and predicted data. The thermal, electrical, as well as overall efficiency of the hPVT collector, improves by 2.73%, 7.11%, and 9.84%, respectively, using Fe/water nanofluid (ϕ = 2%) in contrast to the water-cooled PVT system. Finally, results demonstrate that the outcomes obtained using the forecasted data closely follow the results obtained using the actual data. In conclusion, this analysis provides a comprehensive solution for utilizing nanofluids as a coolant in the most cost-effective ways. [ABSTRACT FROM AUTHOR]

In the last two decades, metallic particles of nano sizes (~10−9 m) have been tested profoundly in volumetric absorption solar collectors (VASC) due to their excellent optical properties and broadband absorption in the entire solar spectrum. However, very limited studies are available for understanding the performance of integrated energy storage VASC systems using nanofluids. For the experimental work presented here, a hybrid nanofluid of gold nanoparticles in Azadirachta indica leaves extract has been synthesized by chemical route. The prepared hybrid nanofluid has shown good absorption in 400 to 700 nm wavelength range and hence achieved high photo‐thermal conversion efficiency for tested VASC system. Furthermore, commercially available paraffin wax is used as a phase change material (PCM) in thermal energy storage (TES) and further integrated with VASC to analyze the thermal performance of the system even after sunshine hours. The real‐time experiments were conducted using different working fluids, and at three mass flow rates, that is, 0.008 kg/s, 0.016 kg/s, and 0.033 kg/s, respectively, during mild winter days in the tropical climate of India. The study revealed a photo‐thermal efficiency enhancement of about 17.1% when hybrid heat transfer fluid was used in the VASC system with TES as compared to base fluid water but without TES. During the heating period, the maximum thermal gain of the hybrid nanofluid was observed to be about 15°C higher than the ambient temperature at mass flow rate of 0.033 kg/s. Thermal efficiency enhancement of about 23.8%, 24%, and 24.1% was observed with hybrid nanofluid compared to base fluid water at a mass flow rate of 0.008 kg/s, 0.016 kg/s, and 0.033 kg/s, respectively, when PCM was kept inside the tank. Furthermore, a maximum zero loss efficiency of 83.8% was estimated at an optimal mass flow rate of 0.033 kg/s for the TES‐integrated VASC system. [ABSTRACT FROM AUTHOR]

Background: The most common cause of mortality in all of India, including the poorer states and rural areas, is coronary artery disease (CAD), despite significant regional variation in the frequency of risk factors. There are several population studies highlighting demographic and socio-economic CAD risk factors. There is paucity of data on CAD especially, more so from rural background. Therefore, the present study was conducted with an aim to analyse the risk factors, clinical presentation and angiographic profile among CAD patients from rural and urban areas. Methods: This Cross-Sectional Clinical Study was conducted among 124 patients with coronary artery disease attending the medicine and cardiology OPD and had admitted in medicine ICCU and wards in medical college and hospital during October 2014 to October 2015. A pretested questionnaire was used to collect the data. Patient found suitable for the study were subjected for clinical, haematological (including CPK- MB), ECG, ECHO and coronary angiography investigations. The data were entered in Microsoft Excel sheet. The data was analysed using SPSS package and appropriate tests like chi-square, 't'-test and ANOVA were applied. Results: Out of 124 patients, 44.4% (55/124) were from rural area and 55.6% (69/124) were from urban area. The mean age of urban subjects was 47.3±8.9 years and 48.4±7.8 years in rural subjects. Female from urban area (31.9%) were having more coronary artery disease when compared with female from rural area (27.3%).STEMI was the most common type of ACS observed among the admitted subjects with CAD from both urban (76.8%) and rural areas (72.7%). Time to onset of symptoms to presentation to hospital was 7-12 hours among 43.6% of subjects form rural area. The coronary angiogram showed obstructive coronary artery disease among 39.1% of subjects form urban area (n=46) and 43.6% of subjects from rural area (n=39). The death rate among rural subjects with CAD (5.5%) was higher than the subjects from urban area (1.4%). Conclusion: In India, under diagnosis and underreporting of CAD is frequently seen among rural people. Economically underprivileged patients with CAD less often receive evidence-based treatments. The distribution of the healthcare workforce, between rural and urban India is not uniform. The earlier notion that the rural population is less prone to CAD is slowly dwindling due to rapid urbanisation of rural lifestyles. [ABSTRACT FROM AUTHOR]

Background: The incidence of CAD is likely to increase further because of rapid urbanization and its accompanying lifestyle changes, as well as an increase in the prevalence of DM, So, the present study was conducted with an aim to make comparison of coronary artery disease risk factors in rural patients and urban patients. Methods: This Cross-Sectional Clinical Study was conducted among 124 patients with coronary artery disease attending the medicine and cardiology OPD and had admitted in medicine ICCU and wards in medical college and hospital during October 2014 to October 2015. Patient found suitable for the study were subjected for clinical, haematological, ECG and ECHO investigations. The data were entered in Microsoft Excel sheet. The data was analysed using SPSS package and appropriate tests like chi-square, 't'-test and ANOVA were applied. Results: Out of 124 patients,44.4% (55/124) were from rural area and 55.6% (69/124) were from urban area. In our study, both in rural and urban subjects, chest pain (94.5% and 97.1% respectively) was predominant symptom. In rural subjects only smoking risk factor was statistically significant among CAD patients (p=0.006). HDL levels were significantly (p=0.028) decreased in rural subjects (36.7±9.2 mg/dL) as compared to urban subjects (39.9±6.9 mg/dL) Conclusion: Conventional risk factors such as smoking, low HDL levels and abdominal obesity play a major role in the causation of premature coronary artery disease among the rural. Lack of awareness, combined with urbanization of rural lifestyle could be responsible for increasing incidence of premature coronary artery disease in them. [ABSTRACT FROM AUTHOR]

Introduction: Appendicitis is a common cause of acute abdominal pain. The diagnosis is eminently clinical and the cause is surgically correctable. However, a decision of surgery based on the clinical presentation only has a 15%-30% chance of the removal of a normal appendix. Thus, the diagnosis involves a corroboration of clinical, laboratory, and radiological findings. Appendicitis scoring systems can be considered to expedite the diagnostic and decision-making process. Aim: The present study was conducted to study the efficacy of Appendicitis Inflammatory Response (AIR) score in the diagnosis of acute appendicitis and its correlation with the histopathological findings. Materials and Methods: A cross-sectional study was conducted at a tertiary care center in North India comprising patients who presented to the surgery department with a provisional diagnosis of acute appendicitis and required appendectomy. Results: Appendicitis was histopathologically proven in 54 patients. Patients with an AIR score ≥5 were 2.18 times more likely to have appendicitis. The probability of having appendicitis with AIR score ≥5 was 92.16% (positive predictive value). The diagnostic accuracy of AIR score was 82.81%. Conclusion: AIR score has a high sensitivity and positive predictive value in the diagnosis of acute appendicitis. It is a quick and convenient system for clinical evaluation of patients in primary care or peripheral hospitals where advanced facilities such as USG scan or CT scan are not available all the time. The application of this scoring system definitely improves diagnostic accuracy and reduces negative appendectomy rate. [ABSTRACT FROM AUTHOR]

Background: Gallbladder carcinoma is endemic in India. Though imaging findings of gallbladder carcinoma are very well-described in the literature, the research question that guided this study was to evaluate various imaging manifestations of the disease in this particular geographic region of North India which is a highly endemic region for gallbladder cancer and compare with studies from other parts of the world. Aims and Objectives: The purpose of the study was to retrospectively analyze the spectrum of findings on Multidetector Computed Tomography (MDCT) in histologically proven gallbladder carcinoma detected at a tertiary care center from the NorthIndia. The primary objective was to define the various patterns of growth while the secondary objective was to analyze the specific prevalence and patterns of spread of the disease. Materials and Methods: We retrospectively studied Contrast-Enhanced Computed Tomography findings in 230 patients of histologically proven gallbladder carcinoma. Patients with previous cholecystectomy or biliary intervention were excluded from the study. Results: In our study, focal or asymmetrical wall thickening of the gallbladder was the most common growth pattern seen in 140 (61%) patients. Contiguous infiltration of the liver was seen in 190 (83%) cases. Regional nodal involvement was observed in 90 (39%) patients, while 100 (43%) patients had both regional and distant nodal involvement. Liver and peritoneal metastases were noted in 71 (31%) patients and 96 (42%) patients, respectively. Majority (81%) of patients had Stage IV disease. Conclusion: MDCT provides comprehensive information regarding the local extent as well as distant spread of gallbladder carcinoma. Asymmetric gall bladder wall thickening in this geographical region must be considered suspicious and should evoke histopathological analysis to exclude malignancy. [ABSTRACT FROM AUTHOR]

Introduction  United States Food and Drug Administration recently approved use of Hemospray for the management of gastrointestinal (GI) Bleeding. We report our experience with Haemoseal Spray (HS, Shaili Endoscopy) for the treatment of upper GI bleeding (UGIB). Methods  Records of patients who received HS for UGIB from January 2013 to June 2018 were studied retrospectively. Patients with UGIB from focal lesions refractory to conventional endotherapy or those with diffuse/multiple lesions not amenable to conventional endotherapy received 5cc HS spray. Primary end-point studied was clinical success, defined as control of bleeding over 24 hours. Secondary end-points evaluated included recurrence of bleeding within 7 days, in-hospital mortality, and complications secondary to HS. Results  Thirty-eight patients were treated with HS. The median age was 57 (range: 5–87) years with 27 males and 11 females. In 24 patients, HS was used as monotherapy, while it was combined with Injection/Clip/Argon Plasma Coagulation in 14. Etiology of bleeding was ulcers or erosions in 22, malignancy in 10, portal hypertensive gastropathy/gastric antral vascular ectasia in 4, and radiation gastropathy in 2. Clinical success was achieved in 32/38 (84%). All six nonresponders had coagulopathy related to chemotherapy/bone marrow transplant. Recurrent bleeding within 7 days was observed in four patients (gastric malignancy 2, radiation gastropathy 2). In-hospital mortality was seen in 8/38 (21%) of which 2(4.8%) were directly related to ongoing GI bleeding. There was no procedure-related complication. Conclusion  HS is an effective and safe tool in the endoscopic management of UGIB due to diffuse or multiple focal lesions or focal lesions refractory to conventional endotherapy. [ABSTRACT FROM AUTHOR]

Background In a developing country like India with intermediate level of prevalence of hepatitis B, most of the patients remain undiagnosed as they are asymptomatic. The purpose of the study was to diagnose asymptomatic HBsAg positive patients from the general population and evaluate further the potential clinical implications of IDAHS. Methods Asymptomatic subjects with unknown HBV status were screened free of cost for hepatitis-B surface antigen. Those who tested positive for HBsAg were further tested to identify those who were potential candidates for anti-viral therapy. To explore the relevance of our screening we assessed potential implications of HBsAg detection. Results A total of 30,836 patients were screened in medical camps over the period of 7 years. Out of these 704 (2.3%) subjects were found to be positive for HBsAg. Distress of being diagnosed with HBV was expressed by 649 (92%) of the positive subjects. High cost of further testing and antiviral therapy, leading to inability to pursue further management was elicited in 510 (72%) of the positive subjects. HBV DNA was detected in 349 (59%) out of 592 subjects, out of which 236 (67%) had high viral load. Conclusion Incidental detection of asymptomatic HBsAg positive subjects was seen in 2.3% of subjects. One third of these patients had an actively replicating virus and required antiviral therapy. Financial support was required in 72% of the subjects for further HBV management. Detecting HBsAg in asymptomatic person in an endemic community has considerable health and psycho-economic impact on the individual. [ABSTRACT FROM AUTHOR]

Background: The issue of tobacco control had almost unanimous support among public health professionals. It is therefore apparent that the dental care system should be involved in tobacco prevention and tobacco cessation. Objective: To assess dental students’ and practicing dentists’ perceptions of tobacco cessation content in curriculum and attitudes concerning their professional responsibility to help users quit tobacco. Methods: The study was conducted with Bachelor of Dental Surgery (BDS) 3rd year students, Interns and practicing dentists of Moradabad city (India). A 17-item questionnaire focused on attitudes of dental fraternity, professional responsibilities, effectiveness and scope of Tobacco Use Cessation (TUC) practice in dental setting. Results: Statically significant difference is seen among responses of dental fraternities, with students having less positive attitudes than practicing dentists (p < 0.001). Conclusion: Attitudes of the participants appear to be positive and encouraging, but they feel unprepared and needed further training in TUC. [ABSTRACT FROM PUBLISHER]

Background & objectives: Hospitalization for medical-illness is associated with an increased risk of deep venous thrombosis (DVT). However, there are no published data from India addressing at this issue. We sought to study the risk factor profile and the incidence of DVT among hospitalized medically-ill patients, a tertiary care hospital in northern India. Methods: All adults admitted to the medical wards and intensive care unit with level 1 or 2 mobility over a period of two years (July 2006 to July 2008) at the All India Institute of Medical Sciences hospital, New Delhi, were prospectively studied. Patients having DVT at admission or an anticipated hospital stay less than 48 h were excluded. The presence of clinical risk factors for DVT was recorded and laboratory evaluation was done for hypercoagulable state. A routine surveillance venous compression Doppler ultrasonography was performed 12 ± 8 days after hospital admission. Results: Of the 163 patients. 77 (47%) had more than one risk factor for DVT. Five (3%) patients developed DVT; none of them had symptomatic DVT. None of these patients received anticoagulation prior to the development of DVT. The mean age of those who developed DVT was 40 ± 13 (25-501 yr; two of five were male. The incidence rate of DVT was 2.7 per 1000 person-days of hospital stay [95% confidence interval (CI): 0.87 to 6.27]. None of the factors was found to be significantly associated with the risk of DVT. Interpretation & conclusions: In our setting, although many hospitalized medically-ill patients had risk factors for DVT, the absolute risk of DVT was low compared to the western population but clearly elevated compared to non hospitalized patients. Large studies from India are required to confirm our findings. [ABSTRACT FROM AUTHOR]

Background: Adalimumab has emerged as a useful drug for treating patients with Crohn's disease (CD) and ulcerative colitis (UC), not responding to conventional therapy. There is limited data on effectiveness and safety of adalimumab biosimilar in patients with inflammatory bowel disease (IBD)., Methods: Patients with IBD who received at least one dose of adalimumab biosimilar from October 2015 to February 2018 were retrospectively included in this multicenter data analysis. Its effectiveness in inducing and maintaining clinical remission at 8, 26, and 52 weeks for CD and UC and safety profile of the drug was studied., Results: Seventy patients (49 CD; 21 UC) with a median age of 39 (range 13-73) years, male predominance (64.3%), and median (IQR) disease duration of 72 (33-104) months were included. Adalimumab biosimilar was effective in inducing remission (at 8 weeks) in 46.9% and 52.4% patients with CD and UC, respectively, of whom  32.7% and 33.3% (three fourths of remitters) maintained remission over 1 year, respectively. Twenty (28.6%) patients experienced adverse events; seven (10%) were serious of whom  three had developed tuberculosis., Conclusions: Adalimumab biosimilar in usual clinical practice is safe and effective in inducing and maintaining remission in Indian patients with IBD. Steroid-free clinical remission was observed in one third of patients with UC and CD at 1 year of therapy. Graphical Abstract.

Aim: To determine the incidence and risk factors for colorectal cancer (CRC) in patients with ulcerative colitis from a low prevalence region for CRC., Methods: Our prospective database yielded a cohort of 430 patients [age: 44 ± 14.6 years; 248 men (57.7%)] with ulcerative colitis (median disease duration 6, range: 1-39 years) for analysis. Of these, 131 (30.5%) had left-sided colitis and 159 (37%) extensive colitis. Patients with histologically confirmed CRC within the segment with colitis were compared with those without CRC, to determine the risk factors for the development of CRC., Results: Twelve patients (2.8%) developed CRC. The overall incidence density was 3.56/1000 patient-years of disease - 3/1000 in the first 10 years, 3.3/1000 at 10 to 20 years, and 7/1000 at > 20 years. Three of our 12 patients developed CRC within 8 years of disease onset. On univariate analysis, extensive colitis, longer duration of disease, and poor control of disease were associated with development of CRC. On multivariate analysis, duration of disease and extent of colitis remained significant., Conclusion: CRC occurred in 2.8% of patients with ulcerative colitis in our population - an incidence density similar to that in Western countries in spite of a low overall prevalence of colon cancer in our population. The risk increased with extent and duration of disease.