Laser Synthesis of Platinum Single-Atom Catalysts for Hydrogen Evolution Reaction.

Platinum (Pt)-based heterogeneous catalysts show excellent performance for the electrocatalytic hydrogen evolution reaction (HER); however, the high cost and earth paucity of Pt means that efforts are being directed to reducing Pt usage, whilst maximizing catalytic efficiency. In this work, a two-step laser annealing process was employed to synthesize Pt single-atom catalysts (SACs) on a MOF-derived carbon substrate. The laser irradiation of a metal-organic framework (MOF) film (ZIF67@ZIF8 composite) by rapid scanning of a ns pulsed infrared (IR; 1064 nm) laser across the freeze-dried MOF resulted in a metal-loaded graphitized film.

Laser scribed proton exchange membranes for enhanced fuel cell performance and stability.

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) offer solutions to challenges intrinsic to low-temperature PEMFCs, such as complex water management, fuel inflexibility, and thermal integration. However, they are hindered by phosphoric acid (PA) leaching and catalyst migration, which destabilize the critical three-phase interface within the membrane electrode assembly (MEA). This study presents an innovative approach to enhance HT-PEMFC performance through membrane modification using picosecond laser scribing, which optimises the three-phase interface by forming a graphene-like structure that mitigates PA leaching.

Characteristics of Acid Leaching and Vibration Coupling Desorption of Gas-Saturated Coking Coal.

Permeability is a key factor affecting efficient gas drainage from coal seams, and acidification and vibration shock are effective means to increase permeability in original low-permeability coal seams. To study the gas desorption characteristics of coking coal under the coupling effect of mining disturbance and acidification permeability enhancement, taking the coal seam of Shoushan No. 1 coal as the research object, a self-built adsorption-desorption vibration test platform was used.

Optimization of the Layer Location of Extraction Wells Based on the Unpressurized Gas Transport Law.

Protective layer mining is one of the most effective measures to control outbursts of coal seam gas in coal mines. Accurately grasping the overlying rock movement and pressure-relief gas migration patterns under protective layer mining conditions is a prerequisite for efficient surface coalbed methane extraction; it is the basis for green emission reduction in coal mines. A physical model was established using the Ji-33200 working face of Pingmei Shi Mine as the research object, and a method combining theoretical calculation and numerical simulation was used to obtain the overlying rock movement.

Laser Synthesis of Nonprecious Metal-Based Single-Atom Catalysts for Oxygen Reduction Reaction.

Development of nonprecious metal-based single-atom catalysts (SACs) has provided opportunities to substitute Pt group metals and offer maximum atom utilization and unique coordination environments. Among these catalysts, Fe-N-C catalysts with atomically dispersed Fe-N active sites have emerged as some of the most promising oxygen reduction reaction (ORR) catalysts. However, furnace synthesis of Fe-N-C catalysts with carbon substrate derived from metal-organic framework (MOF) involves a high-temperature procedure, in which nitrogen from the carbonized MOF tends to be removed, subsequently leading to a low density of active sites.

Effect of membrane thermal conductivity on ion current rectification in conical nanochannels under asymmetric temperature.

Nowadays, there have been extensively theoretical studies on the phenomenon of ion current rectification (ICR) induced by the asymmetric electrical double layer (EDL). As a key factor influencing the behavior of ion transport, temperature is given high priority by researchers. The thermal conductivity of the material commonly employed to prepare nanopores is 2-3 times higher than that of liquid solutions, which may affect ion transport within the nanochannel.

Reversible Ionic Liquid Intercalation for Electrically Controlled Thermal Radiation from Graphene Devices.

Using graphene as a tunable optical material enables a series of optical devices such as switchable radar absorbers, variable infrared emissivity surfaces, or visible electrochromic devices. These devices rely on controlling the charge density on graphene with electrostatic gating or intercalation. In this paper, we studied the effect of ionic liquid intercalation on the long-term performance of optoelectronic devices operating within a broad infrared wavelength range.

Web-Based Access to Positive Airway Pressure Usage with or without an Initial Financial Incentive Improves Treatment Use in Patients with Obstructive Sleep Apnea.

Study Objectives: We tested whether providing adults with obstructive sleep apnea (OSA) with daily Web-based access to their positive airway pressure (PAP) usage over 3 mo with or without a financial incentive in the first week improves adherence and functional outcomes.

Setting: Academic- and community-based sleep centers.

Participants: One hundred thirty-eight adults with newly diagnosed OSA starting PAP treatment.

[Effect of alpha-zearalanol on the generation of reactive oxygen species (ROS) and ROS-activated signal transduction in tumor necrosis factor alpha-stimulated human endothelial cells].

Objective: To investigate the effects of alpha-zearalanol (alpha-ZAL) on the generation of reactive oxygen species (ROS) and ROS-activated signal transduction in the tumor necrosis factor (TNF-alpha)-stimulated human umbilical vein endothelial cells (HUVECs).

Methods: HUVECs were cultured and divided into 4 groups: (1) normal control group, (2) TNF-alpha stimulated group, undergoing TNF-alpha stimulation for 24 h, (3) alpha-ZAL retreatment group, undergoing re-treatment with alpha-ZAL of the concentrations of 1 x 10(-8), 1 x 10(-7), or 1 x 10(-6) mol/L for 1 h, then stimulation of TNF-alpha for 24 h, and (4) plasmid transfection group, transfected with p47(phox) siRNA for 24 h to block the NADPH oxidase protein subunit p47(phox) in the HUVECs, or transfected with blank plasmid as control. The intracellular ROS production was detected by using 2, 7-dichlorofluorescin diacetate as probe.

Inhibitory effects of alpha-zearalenol on angiotensin II-induced integrin beta3 mRNA via suppression of nuclear factor-kappaB.

Objective: To investigate the effect of alpha-zearalenol on angiotensin II-induced beta3 integrin mRNA expression in human umbilical vein endothelial cells (HUVECs).

Methods: The mRNA level in integrin beta3 was determined by reverse transcription-polymerase chain reaction. Endothelial NF-kappaB activity was determined by the luciferase activity assay of plasmid NF-kappaB-LUC.

Angiotensin II stimulates endothelial integrin beta3 expression via nuclear factor-kappaB activation.

The present study examined the effect and part mechanism of angiotensin II-stimulated integrin beta3 gene expression in human umbilical vein endothelial cells. Protein level and mRNA level of integrin beta3 expression were determined using enzyme-linked immunoadsorbent assay and reverse transcription-polymerase chain reaction. Four plasmids of 5'-different deletion of integrin beta3 gene promoter were constructed to transiently transfected into cells to uncover the region in response to angiotensin II.

TSC-36/FRP inhibits vascular smooth muscle cell proliferation and migration.

Objective: In-stent restenosis is a vascular proliferation/migration disorder characterized by hyperplasia of vascular smooth muscle cells (VSMCs). Because mounting evidence suggests that the therapeutic potential of anti-proliferation and anti-migration therapy, we investigated possible inhibitory effects of the matricellular protein TGF-beta-stimulated clone 36 (TSC-36) on vascular smooth muscle cell proliferation and migration in vitro and in vivo.

Methods: Human umbilical artery smooth muscle cells (SMCs) were treated with inducting agents daidzein or estradiol.

Roles of NF-kappaB and SP-1 in oxidative stress-mediated induction of platelet-derived growth factor-B by TNFalpha in human endothelial cells.

Platelet-derived growth factor-B (PDGF-B) is upregulated by proinflamatory stimuli in the early stages of atherosclerosis. However, its mechanisms are not fully elucidated. In the present study, by using the antioxidant N-acetylcysteine (NAC), we investigated in human umbilical vein endothelial cells (HUVECs) the roles of oxidative stress in PDGF-B expression induced by tumor necrosis factor alpha (TNFalpha) and its underlying mechanisms.

[Identification of a novel splice mutation of low density lipoprotein receptor gene in a Chinese family with familial hypercholesterolemia].

Objective: To identify the mutation of low density lipoprotein receptor(LDLR) gene in a large Chinese family with familial hypercholesterolemia(F H) and make a discussion on the pathogenesis of FH at the molecular level.

Methods: Investigations were made on a patient with the clinical phenotype of homozygous FH and his parents for mutations of promoter and all 18 exons of LDLR gene. Screening was carried out using Touch down PCR and a g arose gel electrophoresis, combined with DNA sequence analysis.