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The insulating vacuum within the ITER Cryostat has a prime purpose to minimize the heat load on the superconducting coil system by gas thermal conductivity. These coils are shielded from thermal radiation by an 80 K helium-cooled silver-coated thermal shield (TS) consisting of ~500 panels. Leakage within a cryogenic circuit inside the cryostat is considered to be the prime risk to the ITER project’s mission, as leakage could be disabling to the operation of the magnet systems, be extremely challenging to localize and may be inaccessible for repair. To date, four leaks have been detected and localized within in-cryostat components delivered to ITER. Specifically, three of these leaks have been diagnosed within the TS cooling circuits as having been caused by chlorine-induced stress corrosion cracking (SCC). The technique of high-resolution X-ray computed tomography followed by precision cutting for the generation of macros and micros has been applied to successfully characterize small vacuum leaks for the first time. The techniques were further extended to nonleaking cooling pipes and the onset of SCC was observed in many places, indicating the high probability of the development of many thousands of leaks over time. Such analysis has led to the full replacement/repair program for the TSs before they become overly embedded into ITER. This article summarizes how the helium leakage risk is mitigated and details the detection of extensive SCC on the ITER TSs.

Byline: Sanat. Khanna, Ravi. Kanojia, Prema. Menon, Surinder. Rana, B. Thapa, D. Bhasin, K. L. N.. Rao Vascular anomalies involving the small bowel are an uncommon cause of gastrointestinal bleeding [...]

Byline: M. Zameer, R. Kanojia, K. L. N.. Rao, P. Menon, R. Samujh, B. Thapa We report a 12-year-old-boy with gastric lipoma. Upper gastrointestinal (GI) endoscopy with biopsy and abdominal [...]

Byline: K.L.N. Rao, B. Thapa In developing countries, extrahepatic portal vein obstruction (EHPVO) accounts for the majority of cases of portal hypertension. [sup][1] In general, endoscopic treatment of varices is [...]

The prosperity of aircraft transportation together with revolutionary promotion of composite components used in commercial aircraft pose enormous challenges to the aircraft composite assembly and repair (especially uncertainties associated with polymer process parameters control, barely visible defects and non-destructive inspection capability to inspect zero-thickness defects). Therefore, an industry solution owning merits on reliability and repeatability of assembly process is at high demand. Augmented Reality (AR), a human computer interaction technology, possesses its exclusive superiority on its capability of inflicting digital mock-up into physical environment. The above property of AR provides colossal opportunities to be utilised into industrial applications to contribute the realisation of automated, efficient, streamlined and reliable process and assembly. The current ongoing research aims at developing an AR System integrated into aircraft composite bonded assembly and repair as a guidance tool to instruct technicians’ repairing operation, mitigate human errors, and reduce duration of repair and assembly. Upon the accomplishment of the System, the researchers would aim to investigate the incorporation of machine learning and deep network algorithms to enable and significantly improve the interactions between the multitude of process parameters involved in the composites assembly control procedures, solely relying upon the AR geometric data. This will ultimately lead to dramatic reduction of sensors in aircraft assembly, mitigation of in-process analysis time, reduction of process and post-process inspection time, and a higher quality assembly. Stepped scarf composite repair embedded with soft composite patches was selected as the archetype to be brought into effect though hard patches were partially examined as well. The AR System has focused on composite patches assembly and vacuum bagging process to address the predicament of miscellaneous steps and fibre directions.

Electrolysis is the process of decomposition of the liquid, containing ions by passing electricity through it. This process is achieved by an electrolyzer. An alkaline water electrolyzer uses electrical energy to break the chemical bond between hydrogen and oxygen in an alkaline electrolytic medium. The performance of the electrolyzer depends upon various parameters like temperature, pressure, ohmic overpotential, activation overpotential, etc. In this study, various parameters that affect the performance of the electrolyzer are identified and integrated using fundamental thermodynamics and electrochemical equations. A mathematical model is created in MATLAB/SIMULINK to analyse the voltage vs current density plot of the electrolyzer. An attempt is made to optimize the performance of the electrolyzer through the variation of the parameters. It was observed that increasing the operating temperature and decreasing the operating pressure favours the electrolysis process. Also, 30 wt% of KOH solution as electrolyte exhibits the optimal cell voltage as compared to 20 and 40 wt% solutions.

In the present day in the global context, approximately 2 billion internal combustion engines (ICEs) are estimated to be in use. Nearly 7.3 billion metric tons of carbon dioxide (CO2) were released into the atmosphere as per the survey on the transportation sector in 2020, making up 41% of all emissions. To solve pollution challenges related to ICEs, recent advancements of alternatives to ICEs have pushed the globe to establish clean energy sources such as hydrogen fuel cells. The conversion of an ICE vehicle to a fuel cell vehicle is able to add further support to its development besides the 30% emission reduction since the old ICE vehicle would not be discarded. FCEVs are seen as a true replacement between BEVs and ICEs since more energy can be stored in less space as compared to BEVs. The objective of this paper is to analyse the energy consumption of a fuel cell-driven motor in the internal combustion engine vehicle chassis of Maruti 800, through mathematical modelling, then compare the specifications with that of an ICE-driven system. The analysis provides details on the optimization of drive system components to maximise the fuel cell energy consumption efficiency based on fuel cell power source requirements for a range of velocities and road gradients. The modifiable specifications of drive system components in the mathematical model ensure reproducibility for any drive cycles and system scenarios.

A thermo-time domain reflectometry (TDR) probe can function both as a regular probe, for measuring moisture and density, and a dual heat probe, for measuring thermal conductivity, thermal diffusivity, and volumetric heat capacity. This paper describes the design, fabrication, and evaluation of a newly developed thermo-TDR probe. The developed probe was first calibrated for its TDR function in chemicals with known dielectric constants and electrical conductivity. Then the probe was tested in three sands and Kaolin clay at different moisture contents and densities. Available methods for analyses of the thermo-TDR-acquired signals were presented and discussed. The measured thermal properties were also compared against a standard thermal probe KD2 pro. It was found that the thermo-TDR probe has satisfactory accuracy in measurements of soil thermal conductivity, moisture content, and dry density. Based on the test results, recommendations have been provided regarding the use of thermo-TDR probes for geothermal applications.

We describe four classical cases of familial hemophagocytic lymphohistiocytosis (FHL), a macrophage-related, autosomal recessive fatal disorder. Parental consanguinity was present in three cases. All patients presented with fever, neurological involvement of varying degrees, hepatosplenomegaly, cytopenias, deranged liver function tests, and coagulogram, hypofibrinogenemia (three cases), and hyperlipidemia (one case). An antemortem diagnosis could not be made, although it was suspected in one case. Necropsy (done in three cases and postmortem liver biopsy in one case) revealed classical features of FHL. Florid lymphohistiocytic infiltrate exhibiting hemophagocytosis was seen in the bone marrow, liver, spleen, lymph nodes and brain (examined in two case). In addition to this, focal infiltrates were seen in the kidneys, lung, pancreas, testes, adrenals, and skin. Marked lymphoid depletion was seen in one case in the lymph nodes and spleen.

AbstractIntensive tillage in a humid tropical setting on uplands in Claveria, Philippines moves soil downslope, often creating unfavorable soil conditions for crop production. This field study, conducted on Oxisols with slope gradients ranging from 16–22%, evaluated nutrient dynamics for four ox-powered contour tillage systems: 1.) contour moldboard plowing (CMP); 2.) contourridge tillage (CRT); 3.) contour natural grass barrier strips plus contour moldboard plowing (GCMP); and 4.) contour natural grass barrier strips plus contour ridge tillage (GCRT). The four management systems (treatments) were replicated three times on two sites. Eight corn (Zea mays L) crops were grown from 1992 to 1996 Corn residues, vegetative materials, and inorganic fertilizers (80 kg N, 30 kg P, and 30 kg K ha−1) were applied uniformly to all systems. Lime at 3 Mg ha−1was applied in 1992. Soil sampling was conducted within plots initially, and in 1996 was systematic at equally divided compartments along transects. Overall, from 1992 to 1996 the concentration of total C slightly increased, total N slightly decreased, and extractable Ca, K, P, Cu, and Zn increased significantly in all systems. During the four year period, generally, the concentration gradients of extractable P, K and Ca within treatments became steeper, with the higher concentrations occurring at the lower elevation of the CRT and CMP plots and at the lower elevation of individual terraces of GCMP and GCRT plots. In contrast, concentration gradients for Cu and Zn increased linearly from the lower to higher elevation. Soil pH immediately downslope from the grass strips was significantly lower compared to pH in the grass strips. The changes in pH and chemical concentration gradients across the plots and terraces are attributed primarily to tillage translocated soil downslope due to moldboard plowing. Installation of contour grass barrier strips in conjunction with ridge tillage reduced the rate of soil translocation and, thus, the rate of chemical gradient change.

Cultivated steeplands in the humid tropics require better soil management systems to meet increasing food demands. The objective of this 4‐yr study was to evaluate the following four contour soil management systems for corn (Zea maysL.) production: (i) contour moldboard plowing (CP); (ii) ridge tillage (RT); (iii) natural grass barrier strips plus moldboard plowing (GCP); and (iv) grass strips plus ridge tillage (GRT). Eight successive corn crops were grown in limed and fertilized soil from 1992 through 1995. On a total land area basis (cropped area plus the area occupied by the grass strips), the 1995 mean grain yields for RT (10.8 Mg ha−1) and GRT (10.3 Mg ha−1) were significantly greater than yields for CP (10.0 Mg ha−1) and GCP (9.6 Mg ha−1). The corn grain yields for the CP and RT systems before 1995 ranged from 1.3 Mg ha−1in 1992 to 8.4 Mg ha−1in 1993, while comparable GCP and GRT yields ranged from 1.4 to 7.6 Mg ha−1. Excluding the area occupied by the grass strips, the GRT system had the highest 4‐yr average corn yield (7.3 Mg ha−1) followed by the GCP (7.2 Mg ha−1), RT (6.9 Mg ha−1) and CP (6.7 Mg ha−1) systems. Yields improved during the 1994 and 1995 growing seasons when the grass was not permitted to grow as tall. The combination of contour ridge tillage and contour grass strips has potential for sustaining crop productivity on highly erodible steepland soils in the humid tropics.

The on-farm performance of more than 150 000 pre-basic potato (Solanum tuberosum) minitubers of 1–10 g was monitored over two years in contrasting environments in Nepal. Average minituber productivity (grams of basic seed produced per minituber planted) was 171 g in the southern plains and 116 g in the hills. Although the performance of minitubers varied between environments, minituber sizes and potato varieties, the overall results clearly indicated that minitubers can be successfully multiplied by small-scale farmers. This technology therefore allows for the highly decentralized production of basic seed which, in turn, will reduce farmers' dependence on an unreliable and costly supply of bulky conventional seed.

Abstract The clinical profile, malignant potential, and management of 17 children with juvenile polyposis (more than five juvenile polyps) were evaluated clinically and endoscopically. Colonoscopy and polypectomy were done three weekly until colonic clearance was achieved, and thereafter two yearly. All polyps were subjected to histological examination. Mean age was 7.7 years, with a male preponderance (3:1). Presentation was with rectal bleeding (94%), pallor (65%), stunted growth (53%), and oedema (47%), and the mean (SD) duration of symptoms was 33 (27) months. None had a positive family history or any congenital anomaly. Two children had six polyps up to the transverse colon; the rest had numerous polyps all over the colon. All children had juvenile polyps on histology and 10 (59%) had adenomatous changes (dysplasia). Total colectomy was done in six for intractable symptoms. Colon clearance was achieved in eight after an average 3.4 polypectomy sessions, and three were still on the polypectomy programme. In conclusion, juvenile polyposis is commonly associated with low grade dysplasia. Serial colonoscopic polypectomy is effective but colectomy is required for intractable symptoms and when clearance of the colon is not possible.

Introduction: EHPVO has been considered to cause short stature. But, information about growth hormone analysis in extrahepatic portal venous obstruction (EHPVO) in children is limited. We therefore studied these parameters in EHPVO children (< 18 years of age).Methods: The diagnosis of extrahepatic portal venous obstruction (EHPVO) was made on the basis of ultrasound examination. This Prospective study conducted over 52 children of EHPVO with 41 patients in group 1(normal stature) and 11 patients in group 2(short stature) as per NCHS standards. Levels of GH and IGF1 of all patients (n=52) were compared to normal healthy children (n = 20). Levels of normal stature group were also compared to short stature group.Results: Levels of growth hormone was significantly higher in patient population (67.37±25.66 ng/ml) as compared to controls (4.66±2.74 ng/ml), while IGF 1 was significantly lower in patient population (3.85±4.17 ng/ml)as comparison to control population (91.30±60.88 ng/ml). But, there was no difference of growth hormone and IGF 1 levels between group1 and group 2.Conclusion: It is noteworthy here that growth hormone resistance exists in EHPVO. As there was no difference between normal stature and short stature, so, it does not seem to effect on growth. Further studies required to confirm this observation.