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Thermal management of Li-ion battery packs is a critical technological challenge that directly impacts safety and performance. Removal of heat generated in individual Li-ion cells into the ambient is a considerably complicated problem involving multiple heat transfer modes. This paper develops an iterative analytical technique to model conjugate heat transfer in coolant-based thermal management of a Li-ion battery pack. Solutions for the governing energy conservation equations for thermal conduction and convection are derived and coupled with each other in an iterative fashion to determine the final temperature distribution. The analytical model is used to investigate the dependence of the temperature field on various geometrical and material parameters. This work shows that the coolant flowrate required for effective cooling can be reduced significantly by improving the thermal conductivity of individual Li-ion cells. Further, this work helps understand key thermal-electrochemical trade-offs in the design of thermal management for Li-ion battery packs, such as the trade-off between temperature rise and energy storage density in the battery pack.

Expansions of short nucleotide repeats produce several neurological and neuromuscular disorders including Huntington disease, muscular dystrophy, and amyotrophic lateral sclerosis. A common pathological feature of these diseases is the accumulation of the repeat-containing transcripts into aberrant foci in the nucleus. RNA foci, as well as the disease symptoms, only manifest above a critical number of nucleotide repeats, but the molecular mechanism governing foci formation above this characteristic threshold remains unresolved. Here we show that repeat expansions create templates for multivalent base-pairing, which causes purified RNA to undergo a sol-gel transition in vitro at a similar critical repeat number as observed in the diseases. In human cells, RNA foci form by phase separation of the repeat-containing RNA and can be dissolved by agents that disrupt RNA gelation in vitro. Analogous to protein aggregation disorders, our results suggest that the sequence-specific gelation of RNAs could be a contributing factor to neurological disease.

Aim: To evaluate the apoptosis-inducing properties of undoped and silver-doped-zinc-oxide nanoparticles (SDZONs) synthesized using Boswellia serrata against MCF-7 (Luminal-A) and MDA-MB-231 (Triple-negative) breast cancer cell lines. Methodology: Nanostructures were developed by facile biohydrothermal method and characterized by x-ray diffraction (XRD), Fourier transform infrared (FTIR), and high resolution transmission electron microscopy (HR-TEM). The comparative effect of doping and dose concentration of nanostructures on cytotoxicity was measured using MTT and trypan-blue-exclusion assay. Results: SDZONs exhibited greater cytotoxicity (20.71%, 27.31% cell viability) as compared with undoped nanostructures (35.81%, 37.08% cell viability) against MCF 7 and MDA-MB-231, respectively. Conclusion: The activity of biogenic nanostructures was highly dependent on doping, dose, and type of cell lines used. The novel biogenic SDZONs could be exploited as a promising, cost-effective, and environmentally benign strategy to curb breast cancer. Article highlights Undoped zinc oxide nanoparticles (ZONs) and silver-doped zinc oxide nanoparticles (SDZONs) were synthesized by biogenic method utilizing Boswellia serrata. The formations of nanostructures were initially confirmed by the formation of precipitates. x-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) pattern confirms the crystallinity of nanoparticles. FTIR analysis exhibited the presence of various functional groups like phenols, amines, acids, etc. Bioactivity test for in vitro cytotoxicity efficacy against MCF-7 and MDA MB 231 cells. MTT assays and Trypan-blue dye exclusion assay for cytotoxicity was carried out at different concentration of the biogenic nanoparticles. The cytotoxicity activity of 2% SDZONs is higher than undoped ZONs against both the cell lines. The effect of SDZONs is more pronounced in MCF-7 as compared with MDA MB 231. Cytotoxic propensity of nanostructures toward oncogenic cells is influenced by morphology, doping and dose of nanostructure. Novel biogenic silver-doped zinc oxide nanostructures have remarkable cytotoxic potential which enables its application in biomedical attributes. [ABSTRACT FROM AUTHOR]

The intermittent nature of renewable energy generation can be tackled by integrating them with electrochemical energy storage, which can also close the gap between supply and demand effectively. It has recently been demonstrated that Si3N4‐based negative electrodes are a promising option for lithium‐ion batteries due to their large theoretical capacity and appropriate working potential with extremely low polarization. In the present work, Si3N4 was utilized as anode material in all‐solid‐state lithium‐ion battery with lithium borohydride as a solid electrolyte and Li foil placed as a counter electrode. The electrochemical properties were investigated using galvanostatic charge/discharge profiling whereas the mechanism of lithiation delithiation was investigated in detail using x‐ray diffraction (XRD). The highest capacity of the composite materials was obtained as 1700 mAhg−1 at 0.05 C current rate in the first cycle, which is reduced to 370 in 5 cycles. However, a stability in the capacity was observed in subsequent cycles and a retention of almost 88% could be achieved in 150 cycles. The interfacial resistance before and after the electrochemical cycling was observed as 326 Ω and 13 kΩ, respectively which is also supported by the microstructural investigations where the cracks are observed because of thermochemical reactions. [ABSTRACT FROM AUTHOR]

Context: The most common dental diseases are plaque-related infections. In recent years, there has been a lot of concern about caries prevention, especially in the developing countries and lower socio-economic societies. Therefore, there is always a need to find a natural mouthwash that is economical, safe and simple to make in order to improve dental health and be used as a common home treatment. Aim: The aim of the present study was to compare the effect of chlorhexidine, alum, hi-ora and Terminalia chebula extract mouthwashes on salivary Streptococcus mutans and Lactobacilli in 8-13 year old children. Materials and Methods: The sample for the study consisted of 60 school children aged 8-13 years. Children were divided randomly into four groups with 15 children each and were asked to rinse with the prescribed mouthwash once daily for 1 month, a gap period of 2 months and again continue the mouthwashes for one month and then discontinue. Simplified Oral Hygiene Index (OHI-S) and Silness - Loe Plaque Index were recorded at baseline, 15th, 30th, 90th, 120th, and 180th day. 2 ml of unstimulated saliva collection was done at baseline, 15th, 30th,90th, 120th, and 180th day for microbial analysis of Streptococcus mutans and Lactobacillus. The data's obtained was statisticaly analyzed using Kruskal Wallis Test and Repeated measures ANOVA, applied and tabulated using the SPSS software version 25.0. Results: The results of the study indicate that there was a statistically significant reduction in S. mutans and lactobacilli count in all the four study groups. Terminalia chebula extract mouth rinse was found to be the second most significantly effective antibacterial mouth rinse next to chlorhexidine mouthwash. Conclusion: The study demonstrated that alum-containing mouthwash improved plaque inhibition. Herbal mouth rinses such as Hi-ora and Terminalia Chebula have shown promising results, and thus, they can be considered as a newer alternative. [ABSTRACT FROM AUTHOR]

The Coronavirus Disease of 2019 (COVID-19) pandemic had a profound impact on colorectal cancer (CRC) screening and diagnostic testing. During the initial months of the pandemic, there was a sharp decline in colonoscopies performed as many areas were on lockdown and elective procedures could not be performed. In later months, even when routine procedures started being scheduled again, some patients became fearful of contracting COVID during colonoscopy or lost their health insurance, leading to further delays in CRC diagnosis by colonoscopy. Previous studies have reported the dramatic decrease in colonoscopy rates and CRC detection at various institutions across the country, but no previous study has been performed to determine rates of colorectal screening by colonoscopy in Hawai'i where the demographics of CRC differ. The team investigated the pandemic's impact on colonoscopy services and colorectal neoplasia detection at several large outpatient endoscopy centers in Hawai'i and also classified new CRC cases by patient demographics of age, sex, and ethnicity. There were fewer colonoscopies performed in these endoscopy centers in 2020 than in 2019 and a disproportionate decrease in CRC cases diagnosed. Elderly males as well as Native Hawaiians/Pacific Islanders were most impacted by this decrease in CRC detection. It is possible there will be an increase in later stage presentation of CRC and eventual CRC related mortality among these patients. [ABSTRACT FROM AUTHOR]