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As public attention is increasingly drawn toward more sustainable transportation methods, the popularity of electric vehicles (EVs) as part of the solution is rapidly expanding. Operating conditions within EVs can be severe compared to standard combustion powertrains, and the risk of electrical arcing across mechanical surfaces from electric leakage currents incites additional concern. This study employed a series of electro-tribological tests utilizing various moving patterns to improve understanding of the driving conditions for electrically induced bearing damage (EIBD). Rolling ball-on-disk tests were performed with different polyurea-thickened greases. Rotational tests were initially run at various speeds and test durations, but electrical damage was limited. However, electrical damage was unmistakable when a reciprocating motion was used at different track lengths and speeds. These results suggest that the conditions associated with the track length, such as the number of directional changes and speed-dependent film thickness, play a considerable role in forming electrical damage. This work provides critical insights into the mechanisms of EIBD in EVs and other electrical systems. It highlights the importance of understanding the operational conditions that contribute to EIBD, which can lead to improved designs and maintenance practices, ultimately enhancing the efficiency and lifespan of these systems.

Crohn's disease may affect individuals across all age groups. Usually, it tends to start at a young age, hence late onset Crohn's disease may be difficult to diagnose. The incidence of late-onset inflammatory bowel disease in the United States is 4 to 8 per 100,000 per year. The incidence of Crohn's disease is more in the United States and Europe and less in Asia and Africa. This makes it more challenging to suspect Crohn's disease in an elderly individual of Indian origin. It may be confused with Irritable bowel syndrome or Intestinal tuberculosis.

Insulinoma is a rare pancreatic neuroendocrine tumour (PNET) with an incidence rate of 4 per million population, and the most common cause of hypoglycaemia due to endogenous hyperinsulinism. We present the story of a 61-year-old male, who was extensively evaluated at many hospitals for his symptoms of giddiness, uneasiness and recurrent black outs for the last 3 months, his symptoms disappearing with a carbohydrate rich meal or sweets. Random sugar and fasting sugar values noted were low, with elevated insulin and C-peptide levels. Diagnosis of insulinoma was confirmed by a DOTA PET scan involving the tail of the pancreas and then surgically removed. Early detection is crucial for early surgery to allay symptoms. We describe our diagnostic and treatment plan with reference to previously published reports.

Abstract The geochemical analysis of the shallow aquifer sediments of the area of investigation reveals that they are acidic in nature. The mean electrical conductivity of the deposits is 1.16 dS/m that indicates very low or negligible effects of salinity of the sediments of the Rangpur division. The median values of the concentrations of total organic carbon, total nitrogen and sulphur are 0.20%, 0.02% and 58.68 mg/kg, respectively. The trend of the average heavy metal concentrations of the investigated area can be shown as Fe > As > Cu > Zn. The average concentrations of arsenic of the sediments of the study area are 3.52 mg/kg. Sulphur is significantly, positively correlated with copper and zinc (p

Vaccination is supposed to be the most reliable means to end the COVID 19 pandemic, but recently there have been reports of thrombosis and thrombocytopenia in patients receiving the vaccine especially ChAdOx1 nCoV-19 (AstraZeneca University of Oxford and Serum Institute of India). This has been termed as vaccine-induced immune thrombotic thrombocytopenia (VITT), thrombosis with thrombocytopenia syndrome (TTS) and vaccine-induced prothrombotic immune thrombocytopenia (VIPIT). This is a challenging situation and patients are treated with Fondaparinaux and Rivaroxaban after thrombocytopenia is corrected. Herewith, we report a case of VITT who presented to our hospital and was successfully treated over a weeks' time.

Objectives: From the treatment of damaged teeth to replacing missing teeth, dental biomaterials cover the scientific interest of many fields. Dental biomaterials are one of the implants whose effective life depends vastly on their material and manufacturing techniques. The purpose of this review is to summarize the important aspects for metallic dental implants from biomedical, mechanical and materials science perspectives. The review article will focus on five major aspects as mentioned below. Tooth anatomy: Maximizing the implant performance depends on proper understanding of human tooth anatomy and the failure behavior of the implants. Major parts from tooth anatomy including saliva characteristics are explored in this section. Wear mechanisms: The prominent wear mechanisms having a high impact on dental wear are abrasive, adhesive, fatigue and corrosion wear. To imitate the physiological working condition of dental implants, reports on the broad range of mastication force and various composition of artificial saliva have been included in this section, which can affect the tribo-corrosion behavior of dental implants. Dental implants classifications: The review paper includes a dedicated discussion on major dental implants types and their details for better understanding their applicability and characteristics. Implant materials: As of today, the most established dental implant materials are SS316L, cobalt chrome alloy and titanium. Detailed discussion on their material properties, microstructures, phase transformations and chemical compositions have been discussed here. Manufacturing techniques: In terms of different production methods, the lost wax casting method as traditional manufacturing is considered. Selective Laser Melting (SLM) and Directed Energy Deposition (DED) as additive manufacturing techniques (AM) have been discussed. For AM, the relationships between process–property–performance details have been explored briefly. The effectiveness of different manufacturing techniques was compared based on porosity distribution, mechanical and biomechanical properties. Summary: Despite having substantial research available on dental implants, there is a lack of systematic reviews to present a holistic viewpoint combining state-of-the-art from biomedical, mechanical, materials science and manufacturing perspectives. This review article attempts to combine a wide variety of analyzing approaches from those interdisciplinary fields to deliver deeper insights to researchers both in academia and industry to develop next-generation dental implants.

Abstract The Tista is a Trans-Himalayan river that flows through Sikkim and West Bengal states of India and Rangpur division of Bangladesh and finally falls into the Brahmaputra River. The presence of numerous abandoned channels with various degrees of aggradations indicates large migrations of the Tista River. The pH value of groundwater varies from 6.20 to 7.40 which indicate the slightly alkaline to acidic nature of the studied aquifers. The mean abundance of major cations is Na+ > Ca+2 > Mg+2 > K+, whereas the major anions is HCO3 − > Cl− > SO4−2. Among the cations, Na+ is the dominant and K+ is the lowest constituents, whereas HCO3 − is most abundant and SO4−2 is the minor constituents in anions. The hydrochemical facies of groundwater show that sodium, sodium–magnesium, sodium–calcium, sodium–magnesium–calcium and sodium–calcium–magnesium are cation facies and chloride–bicarbonate, bicarbonate–chloride and bicarbonate are anion facies. Correlating with WHO (Guidelines for drinking-water quality, 1, World Health Organisation, Geneva, 1997) and EQS (Environmental quality standard, Department of Environment, Bangladesh, 1989) guideline values for drinking water and public health, it may be concluded that the groundwater of the study area is suitable for all drinking and domestic purposes, where only three samples exceed the maximum allowable limit of potassium. Based on total hardness, SAR, RSC, PI, SSP and MH values, it can be summarized that the groundwater of the investigated area is suitable for irrigation purpose. On the basis of Australian and UNESCO standard, the groundwater of the study area is also suitable for livestock purposes. The Rangpur area is hydrogeologically active by the processes like ion exchange and dissolution. Ca2+, Mg2+ and HCO3 − are produced by the dissolution of limestone and dolomite.

Detection and quantification of biologically-relevant analytes using handheld platforms are important for point-of-care diagnostics, real-time health monitoring, and treatment monitoring. Among the various signal transduction methods used in portable biosensors, photoelectrochemcial (PEC) readout has emerged as a promising approach due to its low limit-of-detection and high sensitivity. For this readout method to be applicable to analyzing native samples, performance requirements beyond sensitivity such as specificity, stability, and ease of operation are critical. These performance requirements are governed by the properties of the photoactive materials and signal transduction mechanisms that are used in PEC biosensing. In this review, we categorize PEC biosensors into five areas based on their signal transduction strategy: (a) introduction of photoactive species, (b) generation of electron/hole donors, (c) use of steric hinderance, (d) in situ induction of light, and (e) resonance energy transfer. We discuss the combination of strengths and weaknesses that these signal transduction systems and their material building blocks offer by reviewing the recent progress in this area. Developing the appropriate PEC biosensor starts with defining the application case followed by choosing the materials and signal transduction strategies that meet the application-based specifications.

Opsoclonus-myoclonus ataxia (OMA) syndrome is rare in children, mostly caused by neuroblastoma. Here, we present two very rare cases presenting with OMA due to falciparum malaria. Both of them responded to a high dose of adrenocorticotrophin hormone and intravenous immunoglobulin without recurrence and complication.

Arachis hypogea is a non–“infection thread” (IT) legume where rhizobial entry or dissemination in the nodules never involves IT. Rhizobia invade through epidermal “cracks” and directly access the cortical cells to develop the characteristic aeschynomenoid nodules. For investigating these nonclassical nodulation features in Arachis spp., we developed an efficient procedure for Agrobacterium rhizogenes R1000-mediated transformation of this plant. In this study, we optimized the induction of hairy roots and nodulation of composite Arachis hypogea plants in the presence of Bradyrhizobium sp. (Arachis) strain NC92. 35S promoter-driven green fluorescent protein and β-glucuronidase expression indicated transformation frequency to be above 80%. The transformed roots had the characteristic rosette-type root hairs and had normal level of expression of symbiosis-related genes SymRK and CCaMK. The transgenic nodules resembled the wild-type nodules with an exception of 2 to 3%, where they structurally deviated from the wild-type nodules to form nodular roots. A 16S rRNA profile of an infected-zone metagenome indicated that identical populations of bradyrhizobia invaded both composite wild-type plants grown in natural soil. Our results demonstrate that Arachis hairy root is an attractive system for undertaking investigations of the nonclassical features associated with its nitrogen-fixing symbiotic interactions.

In this paper, we conduct a systematic study of human-initiated cascading failures in three critical inter-dependent societal infrastructures due to behavioral adaptations in response to a crisis. We focus on three closely coupled socio-technical networks here: (i) cellular and mesh networks, (ii) transportation networks and (iii) mobile call networks. In crises, changes in individual behaviors lead to altered travel, activity and calling patterns, which influence the transport network and the loads on wireless networks. The interaction between these systems and their co-evolution poses significant technical challenges for representing and reasoning about these systems. In contrast to system dynamics models for studying these interacting infrastructures, we develop interaction-based models in which individuals and infrastructure elements are represented in detail and are placed in a common geographic coordinate system. Using the detailed representation, we study the impact of a chemical plume that has been released in a densely populated urban region. Authorities order evacuation of the affected area, and this leads to individual behavioral adaptation wherein individuals drop their scheduled activities and drive to home or pre-specified evacuation shelters as appropriate. They also revise their calling behavior to communicate and coordinate among family members. These two behavioral adaptations cause flash-congestion in the urban transport network and the wireless network. The problem is exacerbated with a few, already occurring, road closures. We analyze how extended periods of unanticipated road congestion can result in failure of infrastructures, starting with the servicing base stations in the congested area. A sensitivity analysis on the compliance rate of evacuees shows non-intuitive effect on the spatial distribution of people and on the loading of the base stations. For example, an evacuation compliance rate of 70% results in higher number of overloaded base stations than the evacuation compliance rate of 90%.