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  1. Article ; Online: Analysis of energy storage materials for developments in solar cookers [version 2; peer review

    Rahul Goyal / Ravi Kumar Sharma / Rahul Khatri

    F1000Research, Vol

    2 approved]

    2023  Volume 11

    Abstract: Solar energy is accessible freely and can be utilized for many household and industrial applications. The consumption of solar energy for cooking applications has found significant success. Various innovations have been employed in facilitating cooking ... ...

    Abstract Solar energy is accessible freely and can be utilized for many household and industrial applications. The consumption of solar energy for cooking applications has found significant success. Various innovations have been employed in facilitating cooking during off-sunshine hours. Thermal energy storage helps in overcoming the fluctuations in the supply of energy required for cooking during different time periods of the day. This study focuses on the different types of thermal energy storage mediums that are currently utilized in solar cooking. Primarily, oils and pebbles are most commonly used as sensible heat storage (SHS) while organic phase change materials (PCMs) are used as latent heat thermal energy storage materials (LHTES). The properties and performances of various SHS and latent heat storage (LHS) mediums have been compared for their suitable utilization. SHS materials are cost-effective but have lower thermal gradient compared to LHTES materials. The energy storage capability of LHTES is high while degradation with the increasing number of charging and discharging cycles is also considerable. The melting point should be close to the utilization temperature for being used as LHTES as thermal diffusivity of the materials greatly influences the performance of solar cookers. The cooking time is lower for solar cooking systems equipped with energy storage compared to non-equipped cooking systems. It is recognized that the use of energy storage has been proved as a huge advantage to solar cooking systems, however, the design, and heat transfer characteristics of the cooking vessel along with the storage material type and volume must be optimized in order to make this technology more influential.
    Keywords Solar Energy ; Solar Cooker ; Energy Storage ; Sensible Heat ; Latent Heat ; Storage Capacity ; eng ; Medicine ; R ; Science ; Q
    Subject code 621
    Language English
    Publishing date 2023-02-01T00:00:00Z
    Publisher F1000 Research Ltd
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Intrapancreatic MSC transplantation facilitates pancreatic islet regeneration

    Rahul Khatri / Sebastian Friedrich Petry / Thomas Linn

    Stem Cell Research & Therapy, Vol 12, Iss 1, Pp 1-

    2021  Volume 14

    Abstract: Abstract Background Type 1 diabetes mellitus (T1D) is characterized by the autoimmune destruction of the pancreatic β cells. The transplantation of mesenchymal stromal/stem cells (MSC) was reported to rescue the damaged pancreatic niche. However, there ... ...

    Abstract Abstract Background Type 1 diabetes mellitus (T1D) is characterized by the autoimmune destruction of the pancreatic β cells. The transplantation of mesenchymal stromal/stem cells (MSC) was reported to rescue the damaged pancreatic niche. However, there is an ongoing discussion on whether direct physical contact between MSC and pancreatic islets results in a superior outcome as opposed to indirect effects of soluble factors released from the MSC entrapped in the lung microvasculature after systemic administration. Hence, MSC were studied in direct contact (DC) and indirect contact (IDC) with murine pancreatic β cell line MIN6-cells damaged by nitrosourea derivative streptozotocin (STZ) in vitro. Further, the protective and antidiabetic outcome of MSC transplantation was evaluated through the intrapancreatic route (IPR) and intravenous route (IVR) in STZ-induced diabetic NMRI nude mice. Methods MSC were investigated in culture with STZ-damaged MIN6-cells, either under direct contact (DC) or separated through a semi-permeable membrane (IDC). Moreover, multiple low doses of STZ were administered to NMRI nude mice for the induction of hyperglycemia. 0.5 × 106 adipose-derived mesenchymal stem cells (ADMSC) were transferred through direct injection into the pancreas (IPR) or the tail vein (IVR), respectively. Bromodeoxyuridine (BrdU) was injected for the detection of proliferating islet cells in vivo, and real-time polymerase chain reaction (RT-PCR) was employed for the measurement of the expression of growth factor and immunomodulatory genes in the murine pancreas and human MSC. Phosphorylation of AKT and ERK was analyzed with Western blotting. Results The administration of MSC through IPR ameliorated hyperglycemia in contrast to IVR, STZ, and non-diabetic control in a 30-day window. IPR resulted in a higher number of replicating islet cells, number of islets, islet area, growth factor (EGF), and balancing of the Th1/Th2 response in vivo. Physical contact also provided a superior protection to MIN6-cells from STZ ...
    Keywords Adipose-derived mesenchymal stem cells ; Type 1 diabetes mellitus ; Intrapancreatic route ; Intravenous route ; β cell protection ; Medicine (General) ; R5-920 ; Biochemistry ; QD415-436
    Subject code 610
    Language English
    Publishing date 2021-02-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Intrauterine fetal death due to true knot on umbilical cord

    Bhoomika Jain / Rahul Khatri / Devadatta Dabholkar / Sushil Kumar

    MGM Journal of Medical Sciences, Vol 7, Iss 1, Pp 46-

    Report of two cases

    2020  Volume 49

    Abstract: The incidence of a true knot of the umbilical cord is not only very low ranging from 0.3% to 2.1%, but also it often remains undiagnosed antenatally despite the availability of ultrasonography (USG). If the true knot remains tight, it may impede the ... ...

    Abstract The incidence of a true knot of the umbilical cord is not only very low ranging from 0.3% to 2.1%, but also it often remains undiagnosed antenatally despite the availability of ultrasonography (USG). If the true knot remains tight, it may impede the circulation of the fetus and results in intrauterine fetal death (IUFD). We reported two cases of the true knot of the umbilical cord that ultimately led to fetal demise. Our first patient was a 25-year-old primigravida, with a singleton pregnancy of 35 weeks reported with complaints of absent fetal movements for the day. On examination, the patient was normotensive; the fundal height corresponded with the gestational age. The fetal heart sounds were absent on auscultation. The ultrasound confirmed IUFD. Labor was induced and the patient underwent uneventful vaginal delivery. However, the baby was stillborn. Two tight loops of the umbilical cord around the neck with true knots were found. Our second patient was gravida 2 with previous cesarean delivered 3 years back. She was pregnant 25 weeks and had a loss of fetal movement for the day. The fetal heart sounds were absent. She went into spontaneous labor and delivered vaginally. On examination, the true knot in the umbilical cord was seen.
    Keywords intrauterine fetal death ; loops of cord around the neck of fetus ; nuchal cord ; true knot of umbilical cord ; Medicine ; R
    Subject code 610
    Language English
    Publishing date 2020-01-01T00:00:00Z
    Publisher Wolters Kluwer Medknow Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Giant Vesical Calculus in a Girl Child

    Praveen Jhanwar / Vivek Parasher / Rahul Khatri / Vikas Gupta

    MAMC Journal of Medical Sciences, Vol 4, Iss 1, Pp 54-

    Rare Case Report

    2018  Volume 54

    Keywords Medicine ; R
    Language English
    Publishing date 2018-01-01T00:00:00Z
    Publisher Wolters Kluwer Medknow Publications
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Regulation of somatostatin expression by vitamin D3 and valproic acid in human adipose-derived mesenchymal stem cells

    Luise Doering / Rahul Khatri / Sebastian Friedrich Petry / Heinrich Sauer / Hans-Peter Howaldt / Thomas Linn

    Stem Cell Research & Therapy, Vol 10, Iss 1, Pp 1-

    2019  Volume 11

    Abstract: Abstract Background Adipose-derived mesenchymal stem cells (ADMSC) are non-haematopoietic, fibroblast-like multipotent progenitor cells. They have the potential for trilineage (adipocyte, chondrocyte and osteocyte) differentiation as well as ... ...

    Abstract Abstract Background Adipose-derived mesenchymal stem cells (ADMSC) are non-haematopoietic, fibroblast-like multipotent progenitor cells. They have the potential for trilineage (adipocyte, chondrocyte and osteocyte) differentiation as well as differentiation into endocrine pancreatic progenitors. In diabetic or cancer therapy, somatostatin (SST) expression plays a vital role. Small molecules such as valproic acid (VPA) and micronutrients like vitamin D3 have differentiation potential in ADMSC. Therefore, the aim of this study was to investigate the role of vitamin D3 machinery and its metabolic enzymes in ADMSC. Furthermore, the reprogramming effect of vitamin D3 and VPA was evaluated on somatostatin expression in pancreatic lineage differentiation. Methods ADMSC were characterised based on their cell surface marker profile using flow cytometry. Specific adipogenic and osteogenic differentiation protocols were used in this study. Gene expression of several pluripotent, endodermal, pancreatic progenitor and pancreatic endocrine lineage markers were investigated in native ADMSC and after stimulation with different concentration of vitamin D3 for five consecutive days (0, 50, 100, 150 nM) and VPA (0.5, 1, 1.5, 2 mM) by real-time PCR. Furthermore, somatostatin expression was confirmed with ELISA and immunocytochemistry. Results In ADMSC, the expression of somatostatin mRNA, the vitamin D receptor (VDR) and its metabolising enzymes 1 α-Hydroxylase, 24-Hydroxylase and 25-Hydroxylase were detected. Upon stimulation with vitamin D3, nuclear translocation of vitamin D receptor (VDR) was observed. Interestingly, the presence of vitamin D3 reduced the transcription of the somatostatin gene. By contrast, VPA treatment of cultivated ADMSC showed enhancing effect on somatostatin gene expression. No other pluripotent, endodermal, pancreatic progenitor or pancreatic endocrine lineage mRNA expression was modulated under the influence of vitamin D3 and VPA. Conclusion Human ADMSC carry the VDR. The vitamin D metabolising enzyme ...
    Keywords Human adipose-derived mesenchymal stem cells ; Somatostatin expression ; Medicine (General) ; R5-920 ; Biochemistry ; QD415-436
    Subject code 570
    Language English
    Publishing date 2019-08-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Regenerative Therapy of Type 1 Diabetes Mellitus

    Nadine E. Rekittke / Meidjie Ang / Divya Rawat / Rahul Khatri / Thomas Linn

    Stem Cells International, Vol

    From Pancreatic Islet Transplantation to Mesenchymal Stem Cells

    2016  Volume 2016

    Abstract: Type 1 diabetes is an autoimmune disease resulting in the permanent destruction of pancreatic islets. Islet transplantation to portal vein provides an approach to compensate for loss of insulin producing cells. Clinical trials demonstrated that even ... ...

    Abstract Type 1 diabetes is an autoimmune disease resulting in the permanent destruction of pancreatic islets. Islet transplantation to portal vein provides an approach to compensate for loss of insulin producing cells. Clinical trials demonstrated that even partial islet graft function reduces severe hypoglycemic events in patients. However, therapeutic impact is restrained due to shortage of pancreas organ donors and instant inflammation occurring in the hepatic environment of the graft. We summarize on what is known about regenerative therapy in type 1 diabetes focusing on pancreatic islet transplantation and new avenues of cell substitution. Metabolic pathways and energy production of transplanted cells are required to be balanced and protection from inflammation in their intravascular bed is desired. Mesenchymal stem cells (MSCs) have anti-inflammatory features, and so they are interesting as a therapy for type 1 diabetes. Recently, they were reported to reduce hyperglycemia in diabetic rodents, and they were even discussed as being turned into endodermal or pancreatic progenitor cells. MSCs are recognized to meet the demand of an individual therapy not raising the concerns of embryonic or induced pluripotent stem cells for therapy.
    Keywords Internal medicine ; RC31-1245
    Subject code 610
    Language English
    Publishing date 2016-01-01T00:00:00Z
    Publisher Hindawi Limited
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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