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Improved Gas Pattern Recognition with GAN-Enhanced Edge Platform for Gas Sensors Monitoring System
No full textPool-boiling enhancement on periodic micro/nano ripple-structured surfaces fabricated by femtosecond laser
No full textA study was conducted on whether periodic micro/nano ripple structures generated on metal surfaces using femtosecond laser processing could improve pool boiling heat transfer. Depending on the laser irradiation conditions on the metal surface, a surface structure with different geometrical characteristics is created. Changes in sample surface morphology caused by the laser irradiation intensity are examined using scanning electron microscopy and confocal laser microscopy. Pool boiling tests are conducted to compare three laser irradiation conditions fabricated samples and the bare copper surface. The working fluid is deionized water. The pool boiling curves of each sample surface were compared with each other. Visualization of bubble nucleation is performed using a high-speed camera. The superheat, bubble departure diameter, and bubble growth period of each sample are measured and compared at the onset of nucleate boiling (ONB). The most efficient periodic micro/nano ripple-structured surface reduces the superheat at the ONB by 6.13 degrees C in comparison with that at the bare Cu surface. The enhanced surface structure reduced the bubble departure diameter and renewal period by 60.5% and 55.6% in comparison with that of the smooth surface. Further, the structured surface showed 178.5% enhancement in heat transfer coefficient and 39.1% in critical heat flux, respectively. Thus, the combination of increased nucleate site density, high nucleation site activation, and a wicking effect in the periodic micro/nano ripple structure significantly improves the pool boiling heat transfer
PCNA Ser46-Leu47 residues are crucial in preserving genomic integrity
No full textProliferating cell nuclear antigen (PCNA) is a maestro of DNA replication. PCNA forms a homotrimer and interacts with various proteins, such as DNA polymerases, DNA ligase I (LIG1), and flap endonuclease 1 (FEN1) for faithful DNA replication. Here, we identify the crucial role of Ser46-Leu47 residues of PCNA in maintaining genomic integrity using in vitro, and cell-based assays and structural prediction. The predicted PCNA(& UDelta;SL47) structure shows the potential distortion of the central loop and reduced hydrophobicity. PCNA(& UDelta;SL47) shows a defective interaction with PCNA(WT) leading to defects in homo-trimerization in vitro. PCNA(& UDelta;SL47) is defective in the FEN1 and LIG1 interaction. PCNA ubiquitination and DNA-RNA hybrid processing are defective in PCNA(& UDelta;SL47)-expressing cells. Accordingly, PCNA(& UDelta;SL47)-expressing cells exhibit an increased number of single-stranded DNA gaps and higher levels of & gamma;H2AX, and sensitivity to DNA-damaging agents, highlighting the importance of PCNA Ser46-Leu47 residues in maintaining genomic integrity
MOF-derived Co/Zn single-atom catalysts for reversible hydrogenation and dehydrogenation of quinoline hydrogen carrier
No full textStorage of hydrogen, particularly liquid organic hydrogen carrier (LOHC), has attracted much attention to address the problem of safe storage and transport of H2. N-heterocycles are promising hydrogen carriers for storing/releasing hydrogen through reversible catalytic hydrogenation/dehydrogenation cycles. Therefore, designing cost-effective, efficient, reusable single catalysts for both processes with high catalytic activity is currently of interest. Herein, we report the successful preparation of atomically dispersed Co/Zn single-atom catalysts on nitrogen-doped carbon by pyrolysis of bimetallic CoxZny-MOF-508@Melamine. The synthesized CoxZny-NC catalyst showed highly efficient catalytic activity for the reversible hydrogenation and dehydroge-nation of quinoline derivatives in the same solvent. Catalytic reversible hydrogen storage/release was demon-strated for three consecutive cycles without losing efficiency. The main features of this work require low loading of catalysts compared to reported heterogeneous non-precious metal catalysts. A control experiment revealed that free N-H groups/N-atoms are essential for dehydrogenation/hydrogenation reactions, and a possible reac-tion mechanism was proposed
Pharmacological GLUT3 salvage augments the efficacy of vitamin C-induced TET2 restoration in acute myeloid leukemia
No full textVitamin C has been demonstrated to regulate hematopoietic stem cell frequencies and leukemogenesis by augmenting and restoring Ten-Eleven Translocation-2 (TET2) function, potentially acting as a promising adjunctive therapeutic agent for leukemia. However, glucose transporter 3 (GLUT3) deficiency in acute myeloid leukemia (AML) impedes vitamin C uptake and abolishes the clinical benefit of vitamin C. In this study, we aimed to investigate the therapeutic value of GLUT3 restoration in AML. In vitro GLUT3 restoration was conducted with the transduction of GLUT3-overexpressing lentivirus or the pharmacological salvage with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) treatment to OCI-AML3, a naturally GLUT3-deficient AML cell line. The effects of GLUT3 salvage were further confirmed in patient-derived primary AML cells. Upregulation of GLUT3 expression made AML cells successfully augment TET2 activity and enhanced the vitamin C-induced anti-leukemic effect. Pharmacological GLUT3 salvage has the potential to overcome GLUT3 deficiency in AML and improves the antileukemic effect of vitamin C treatments
Single-Molecule Force Spectroscopy of Membrane Protein Folding
No full textSingle-molecule force spectroscopy is a unique method that can probe the structural changes of single proteins at a high spatiotemporal resolution while mechanically manipulating them over a wide force range. Here, we review the current understanding of membrane protein folding learned by using the force spectroscopy approach. Membrane protein folding in lipid bilayers is one of the most complex biological processes in which diverse lipid molecules and chaperone proteins are intricately involved. The approach of single protein forced unfolding in lipid bilayers has produced important findings and insights into membrane protein folding. This review provides an overview of the forced unfolding approach, including recent achievements and technical advances. Progress in the methods can reveal more interesting cases of membrane protein folding and clarify general mechanisms and principles
Fast Response-Recovery and High Selectivity Chemicapacitive Detection of a Nerve Agent Simulant Vapor
No full textEarly detection of chemical warfare agents (CWAs) is critical in minimizing the exposure to chemical threats. This study presents a fast response-recovery chemicapacitive sensor (chemicapacitor) for a nerve agent simulant, dimethyl methylphosphonate (DMMP), with high selectivity and sensitivity. Chemicapacitors with interdigitated electrodes were fabricated on a SiO2/Si wafer by aligning single-walled carbon nanotubes (SW-CNTs) coated with polyhedral oligomeric silsesquioxane-supported 1,1,1,3,3,3-hexafluoro-2-propanol (POSS-HFIP) receptors. The stable, nano-sized three-dimensional structure with multiple terminal alcohol groups played a crucial role as a high-performance receptor via efficient hydrogen-bonding interaction with the CWA simulant. The response and recovery times of the fabricated chemicapacitors were estimated to be 13 and 88 s, respectively, outperforming chemiresistive sensors in terms of response-recovery dynamics. The capacitive responses were obtained at varying DMMP vapor concentrations, ranging from 25 to 150 ppm, and they exhibited superior sensitivity compared to receptor-free sensor devices. The concentration-dependent sensitivity was well-fitted with the Langmuir isotherm model, indicating that the sensing mechanism is based on the adsorption/desorption process. In addition, excellent selectivity was realized by introducing different toxic molecules (sulfur dioxide, ammonia, and ethylene oxide) and a blood agent (cyanogen chloride), where the fabricated POSS-HFIP/SW-CNTs chemicapacitor selectively responded to the DMMP vapor. The limit-of-detection was calculated to be 0.70 ppm. The proposed POSS-HFIP/SW-CNTs chemicapacitor demonstrated rapid response-recovery characteristics (with improved selectivity towards DMMP), suggesting its potential in reducing casualties or injuries by early identification of CWAs
Safety, tolerability, pharmacokinetics and pharmacodynamics of multiple ascending doses of the novel long-acting glucagon analogue HM15136 in overweight and obese patients with co-morbidities
No full textAim To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of multiple ascending doses of the novel long-acting glucagon analogue HM15136 in overweight/obese patients with co-morbidities, with and without type 2 diabetes (T2D).Materials and Methods This was a phase 1, double-blind, randomized, placebo-controlled, two-part trial with a 12-week treatment period of once-weekly subcutaneous HM15136 (0.02/0.04/0.06 mg/kg). Part 1 included patients with dyslipidaemia and/or hypertension and no T2D. Part 2 included patients with dyslipidaemia and/or hypertension plus T2D.Results In part 1, 23/27 (85.2%) patients receiving HM15136 and all patients receiving placebo (9/9 [100%]) experienced a treatment-emergent adverse event (TEAE). Five of 27 (18.5%) patients receiving HM15136 developed anti-HM15136 antibodies. Dose-dependent increases in mean HM15136 serum concentration and fasting plasma glucose (FPG) were observed, as were dose-dependent weight reductions of 0.5%/2.3%/2.6% at doses of 0.02/0.04/0.06 mg/kg, respectively. In part 2, 8/12 (66.7%) patients receiving HM15136 and all patients receiving placebo (4/4 [100.0%]) reported a TEAE. Two (16.7%) patients developed anti-HM15136 antibodies. Dose-dependent increases in mean HM15136 serum concentration were observed. FPG of more than 200 mg/dL was reported in 4/9 (44.4%) and 2/3 (66.7%) patients receiving 0.02 and 0.06 mg/kg, respectively. The 0.06 mg/kg dose was not tolerated in part 2 because of hyperglycaemia. Patients receiving 0.02 mg/kg showed a 0.9% weight reduction. No serious TEAEs leading to discontinuation were reported in either study part.Conclusions This study of HM15136 provides a preliminary safety and tolerability profile with initial insights into its efficacy profile
Hong Kong World: Leveraging Structural Regularity for Line-based SLAM
No full textManhattan and Atlanta worlds hold for the structured scenes with only vertical and horizontal dominant directions (DDs). To describe the scenes with additional sloping DDs, a mixture of independent Manhattan worlds seems plausible, but may lead to unaligned and unrelated DDs. By contrast, we propose a novel structural model called Hong Kong world. It is more general than Manhattan and Atlanta worlds since it can represent the environments with slopes, e.g., a city with hilly terrain, a house with sloping roof, and a loft apartment with staircase. Moreover, it is more compact and accurate than a mixture of independent Manhattan worlds by enforcing the orthogonality constraints between not only vertical and horizontal DDs, but also horizontal and sloping DDs. We further leverage the structural regularity of Hong Kong world for the line-based SLAM. Our SLAM method is reliable thanks to three technical novelties. First, we estimate DDs/vanishing points in Hong Kong world in a semi-searching way. We use a new consensus voting strategy for search, instead of traditional branch and bound. This method is the first one that can simultaneously determine the number of DDs, and achieve quasi-global optimality in terms of the number of inliers. Second, we compute the camera pose by exploiting the spatial relations between DDs in Hong Kong world. This method generates concise polynomials, and thus is more accurate and efficient than existing approaches designed for unstructured scenes. Third, we refine the estimated DDs in Hong Kong world by a novel filter-based method. Then we use these refined DDs to optimize the camera poses and 3D lines, leading to higher accuracy and robustness than existing optimization algorithms. In addition, we establish the first dataset of sequential images in Hong Kong world. Experiments showed that our approach outperforms state-of-the-art methods in terms of accuracy and/or efficiency
Multi-contrast digital histopathology of mouse organs using quantitative phase imaging and virtual staining
No full textQuantitative phase imaging (QPI) has emerged as a new digital histopathologic tool as it provides structural information of conventional slide without staining process. It is also capable of imaging biological tissue sections with sub-nanometer sensitivity and classifying them using light scattering properties. Here we extend its capability further by using optical scattering properties as imaging contrast in a wide-field QPI. In our first step towards validation, QPI images of 10 major organs of a wild-type mouse have been obtained followed by H&E-stained images of the corresponding tissue sections. Furthermore, we utilized deep learning model based on generative adversarial network (GAN) architecture for virtual staining of phase delay images to a H&E-equivalent brightfield (BF) image analogues. Using the structural similarity index, we demonstrate similarities between virtually stained and H&E histology images. Whereas the scattering-based maps look rather similar to QPI phase maps in the kidney, the brain images show significant improvement over QPI with clear demarcation of features across all regions. Since our technology provides not only structural information but also unique optical property maps, it could potentially become a fast and contrast-enriched histopathology technique