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Glioblastoma multiforme (GBM; grade IV astrocytoma) is the most prevalent and aggressive form of primary brain cancer. A subpopulation of multipotent cells termed GBM cancer stem cells (CSCs) play a critical role in tumor initiation, tumor maintenance, metastasis, drug resistance, and recurrence following surgery. Here we report the identification of a small molecule, termed RIPGBM, from a cell-based chemical screen that selectively induces apoptosis in multiple primary patient-derived GBM CSC cultures. The cell type-dependent selectivity of this compound appears to arise at least in part from redox-dependent formation of a proapoptotic derivative, termed cRIPGBM, in GBM CSCs. cRIPGBM induces caspase 1-dependent apoptosis by binding to receptor-interacting protein kinase 2 (RIPK2) and acting as a molecular switch, which reduces the formation of a prosurvival RIPK2/TAK1 complex and increases the formation of a proapoptotic RIPK2/caspase 1 complex. In an orthotopic intracranial GBM CSC tumor xenograft mouse model, RIPGBM was found to significantly suppress tumor formation in vivo. Our chemical genetics-based approach has identified a drug candidate and a potential drug target that provide an approach to the development of treatments for this devastating disease.

An audio power amplifier is an electronic device used to amplify a small signal source power at the input into a large signal power at the output that is speaker. In general, audio power amplifiers use class-AB amplifiers. In the process of amplifying the signal power, there will be power losses in the amplifiers which results in relatively lower amplifier power efficiency because there is a difference between the supply and output voltage levels. In this paper a class-G series audio power amplifier for subwoofers is designed to minimize these power losses and increase the power efficiency of the amplifier. The designed amplifier voltage supply is 40 V with a maximum output power of 80 W at an 8 Ω load. The amplifier has frequency response from 20–200 Hz and gain twice. Realization of the power amplifier and measurements were carried out using the circuit maker simulator, and the measurement results of the class-G power amplifier were compared with the class-AB power amplifier. The measurement results show that both power amplifiers meet the design specifications. The proposed class-G amplifier has 0.14% larger total harmonic distortion (THD) but has 10.4% greater power efficiency advantages over the class-AB amplifier. [ABSTRACT FROM AUTHOR]

Summary: Inherited bone marrow failure syndromes (IBMFS) pose significant diagnostic challenges due to overlapping symptoms and variable expressivity, despite evolving genomic insights. The study aimed to elucidate the genomic landscape among 130 Korean patients with IBMFS. We conducted targeted next‐generation sequencing (NGS) and clinical exome sequencing (CES) across the cohort, complemented by whole genome sequencing (WGS) and chromosomal microarray (CMA) in 12 and 47 cases, respectively, with negative initial results. Notably, 50% (n = 65) of our cohort achieved a genomic diagnosis. Among these, 35 patients exhibited mutations associated with classic IBMFSs (n = 33) and the recently defined IBMFS, aplastic anaemia, mental retardation and dwarfism syndrome (AmeDS, n = 2). Classic IBMFSs were predominantly detected via targeted NGS (85%, n = 28) and CES (88%, n = 29), whereas AMeDS was exclusively identified through CES. Both CMA and WGS aided in identifying copy number variations (n = 2) and mutations in previously unexplored regions (n = 2). Additionally, 30 patients were diagnosed with other congenital diseases, encompassing 13 distinct entities including inherited thrombocytopenia (n = 12), myeloid neoplasms with germline predisposition (n = 8), congenital immune disorders (n = 7) and miscellaneous genomic conditions (n = 3). CES was particularly effective in revealing these diverse diagnoses. Our findings underscore the significance of comprehensive genomic analysis in IBMFS, highlighting the need for ongoing exploration in this complex field. [ABSTRACT FROM AUTHOR]

The influence of tetraethyl orthosilicate (TEOS) on the plasma etching behavior of yttrium aluminum garnet (Y3Al5O12, yttrium aluminum garnet [YAG]) was systematically studied. Dense YAG bulk specimens were hot‐press sintered at a relatively low temperature of 1450°C for 2 h under 20 MPa, using TEOS as a sintering additive. The etching properties of YAG ceramics, doped with different TEOS contents, were evaluated using an inductively coupled plasma etcher with an incident plasma power of 1500 W for up to 2 h. It was observed that the addition of.3 wt.% TEOS optimally reduced the surface roughness of YAG ceramics post‐plasma etching. Transmission electron microscopy and X‐ray fluorescence tests clarified that a densification‐promoting TEOS‐induced residual Si‐rich phase at the triple junction for the over‐doped TEOS (≥.5 wt.%) specimen acts as a pit‐initiation site during plasma etching, which eventually results in increased surface roughness. [ABSTRACT FROM AUTHOR]

A zeolitic 4A type material was successfully prepared from natural basalt rock by applying an alkali fusion process and hydrothermal synthesis. In particular, the optimum synthetic conditions were examined at different crystallization times. Several methods such as XRD, SEM, EDX, and N2 and CO2 adsorption analysis were used to characterize the synthesized 4A type zeolite. In addition, CO2 adsorption equilibrium capacities for this basalt base zeolite were measured over temperature ranges from 283 to 303 K and pressure ranges from 0.1 to 1500 kPa in a volumetric adsorption apparatus. Then the results were compared to those of commercial zeolite. Moreover, to further investigate the surface energetic heterogeneity of the prepared zeolite, the isosteric heat of adsorption and adsorption energy distribution was determined. We found that basalt based zeolite 4A shows a CO2 adsorption equilibrium capacity of 5.9 mmol g-1 (at 293 K and 1500 kPa) which is much higher than the 3.6 mmol g-1 of the commercial zeolite as its micro-pore surface area, micro-pore volume and surface heterogeneity indicate.