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In this study, a copper brazing filler metal coating is fabricated on a 304 stainless steel (304SS) substrate using an electroplating technique. The effect of using electroplated copper brazing filler metal coatings compared to pure copper foil of the same thickness for vacuum brazing of stainless steel joints is investigated. The microstructure and microhardness of the brazed joints are characterized using X‐ray diffraction (XRD), scanning electron microscopy (SEM), and a Vickers hardness tester. The shear strength of the brazed joints is measured using an INSTRON 5869 universal testing machine. The results indicate that the electroplated Cu coating is dense, predominantly with a single cubic phase, with a few copper particles aggregating on the surface. Under electroplating conditions of 20 mA cm−2 for 1 h, the coating thickness was 56 μm. The shear strength of the brazed joint with this coating reached a maximum of 333.7 MPa, which is higher than that of a brazed joint with a 60 μm thick copper foil, which exhibits a shear strength of 303.2 MPa. The shear strength of the brazed joints shows an initial increase followed by a decrease as current density and electroplating time increase. This study provides significant technical support for brazing complex shapes or precision components. It suggests a method to simplify the brazing process, reduce production costs, and enhance the strength of brazed joints. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) have recently become highly attractive for selective hydrogenation reactions owing to their remarkably high selectivity. However, compared to their nanoparticle counterparts, atomically dispersed metal atoms in SACs often show inferior activity and are prone to aggregate under reaction conditions. Here, by theoretical calculations, we show that tuning the local electronic structures of metal anchor sites on g‐C3N4 by doping B atoms (BCN) with relatively lower electronegativity allows achieving zero‐valence Pd SACs with reinforced metal‐support orbital hybridizations for high stability and upshifted Pd 4d orbitals for high activity in H2 activation. The precise synthesis of Pd SACs on BCN supports with varied B contents substantiated the theoretical prediction. A zero‐valence Pd1/BCN SAC was achieved on a BCN support with a relatively low B content. It exhibited much higher stability in a H2 reducing environment, and more strikingly, a hydrogenation activity, approximately 10 and 34 times greater than those high‐valence Pd1/g‐C3N4 and Pd1/BCN with a high B content, respectively. [ABSTRACT FROM AUTHOR]

Artificial micro/nanomotors using active particles hold vast potential in applications such as drug delivery and microfabrication. However, upgrading them to micro/nanorobots capable of performing precise tasks with sophisticated functions remains challenging. Bubble microthruster (BMT) is introduced, a variation of the bubble‐driven microrobot, which focuses the energy from a collapsing microbubble to create an inertial impact on nearby target microparticles. Utilizing ultra‐high‐speed imaging, the microparticle mass and density is determined with sub‐nanogram resolution based on the relaxation time characterizing the microparticle's transient response. Master curves of the BMT method are shown to be dependent on the viscosity of the solution. The BMT, controlled by a gamepad with magnetic‐field guidance, precisely manipulates target microparticles, including bioparticles. Validation involves measuring the polystyrene microparticle mass and hollow glass microsphere density, and assessing the mouse embryo mass densities. The BMT technique presents a promising chip‐free, real‐time, highly maneuverable strategy that integrates bubble microrobot‐based manipulation with precise bioparticle mass and density detection, which can facilitate microscale bioparticle characterizations such as embryo growth monitoring. [ABSTRACT FROM AUTHOR]

Huanglian Jiedu decoction (HLJD) has been used to treat ischemic stroke in clinic. However, the detailed protective mechanisms of HLJD on ischemic stroke have yet to be elucidated. The aim of this study is to elucidate the underlying pharmacological mechanisms of HLJD based on the inhibition of neuroinflammation and the amelioration of nerve cell damage. A middle cerebral artery occlusion reperfusion (MCAO/R) model was established in rats and received HLJD treatment. Effects of HLJD on neurological function was assessed based on Bederson's score, postural reflex test and asymmetry score. 2, 3, 5‐Triphenyltetrazolium chloride (TTC) staining, Hematein and eosin (HE) and Nissl staining were used to observe the pathological changes in brain. Then, transcriptomics was used to screen the differential genes in brain tissue in MCAO/R model rats following HLJD intervention. Subsequently, the effects of HLJD on neutrophil extracellular trap (NET) formation‐related neuroinflammation, gamma‐aminobutyric acid (GABA)ergic synapse activation, nerve cell damage and proliferation were validated using immunofluorescence, western blot and enzyme‐linked immunosorbent assay (ELISA). Our results showed that HLJD intervention reduced the Bederson's score, postural reflex test score and asymmetry score in MCAO/R model rats. Pathological staining indicated that HLJD treatment decreased the cerebral infarction area, mitigated neuronal damage and increased the numbers of Nissl bodies. Transcriptomics suggested that HLJD affected 435 genes in MCAO/R rats. Among them, several genes involving in NET formation and GABAergic synapses pathways were dysregulated. Subsequent experimental validation showed that HLJD reduced the MPO+CitH3+ positive expression area, reduced the protein expression of PAD4, p‐P38/P38, p‐ERK/ERK and decreased the levels of IL‐1β, IL‐6 and TNF‐α, reversed the increase of Iba1+TLR4+, Iba1+p65+ and Iba1+NLRP3+ positive expression area in brain. Moreover, HLJD increased GABA levels, elevated the protein expression of GABRG1 and GAT3, decreased the TUNEL positive expression area and increased the Ki67 positive expression area in brain. HLJD intervention exerts a multifaceted positive impact on ischemia‐induced cerebral injury in MCAO/R rats. This intervention effectively inhibits neuroinflammation by mitigating NET formation, and concurrently improves nerve cell damage and fosters nerve cell proliferation through activating GABAergic synapses. [ABSTRACT FROM AUTHOR]

Aims: This study aimed to evaluate the safety of reducing or withdrawing anti‐seizure medications (ASMs) in a cohort comprising both adults and children with drug‐resistant epilepsy (DRE) undergoing ketogenic diet therapy (KDT). Methods: We conducted a comprehensive analysis of clinical profiles in adults and children with DRE who had adhered to KDT for at least 6 months. Successful withdrawal or reduction of an ASM was defined as discontinuation or dose reduction without subsequent resumption or increase and without initiation of any new ASM throughout the entire follow‐up period. Changes in the ASM load were calculated specifically for adult patients. Results: The study enrolled 56 participants (34 children and 22 adults) with DRE, with 64.3% achieving successful withdrawal of at least one ASM. The probability of ASM withdrawal remained consistent for children (64.7%) versus adults (63.6%), as well as for responders (62.5%) versus non‐responders (68.8%), and it was not associated with other clinical factors. Early ASM reduction (including withdrawal) after diet initiation occurred in 15 patients (26.8%), with treatment outcomes comparable to those of the remaining participants. Among the 22 adults, the mean values of ASM load reduced by 24.5%, with a similar magnitude observed for responders (24.2%) versus non‐responders (25.1%). In addition, adults tend to have a slower elevation in serum ketone levels compared to children. Conclusion: This study demonstrates the safe achievability of ASM withdrawal through KDT in most patients with DRE, irrespective of age or seizure frequency reduction. [ABSTRACT FROM AUTHOR]

A numerical method is proposed to evaluate the effect of non‐Gaussian roughness on point contact elastohydrodynamic lubrication (EHL). A mixed EHL model of point contact, considering non‐Gaussian roughness, is developed. The oil film pressure in the model was controlled by the Reynolds equation of average flow, and the contact pressure of asperity was obtained by the rough surface micro‐contact model. The influence of non‐Gaussian roughness parameters on contact pressure distribution, film thickness profile and the ratio of asperity pressure to contact load (asperity load ratio) are investigated based on the mixed EHL model. The results show that the asperity pressure increases as root mean square (RMS) roughness increases, skewness and kurtosis. The film thickness also increases with RMS roughness and skewness, but is not sensitive to kurtosis. [ABSTRACT FROM AUTHOR]

In an article published in Angewandte Chemie, Junling Lu et al. discuss the use of single-atom catalysts (SACs) for selective hydrogenation reactions. SACs are known for their high selectivity but often have lower activity and are prone to aggregation. The researchers found that by tuning the electronic structures of anchor sites on g-C3N4 through the doping of boron atoms with low electronegativity, they were able to achieve zero-valence Pd SACs with improved hydrogenation activity and stability. This research provides insights into enhancing the performance of SACs for advanced hydrogenation applications. [Extracted from the article]

In the treatment of kidney diseases such as chronic kidney disease (CKD) and acute tubular necrosis (ATN), prolonged contact between conductivity sensors and patients' bodily fluids is required, necessitating high biocompatibility for the electrodes. However, the widely used graphite electrodes exhibit limited biocompatibility, showing a cell survival rate of only 88% under indirect contact conditions, and <56% under direct contact conditions. Here, the surface detachment of graphite electrodes in liquid environments leading to cell death upon contact is observed and a solution is proposed to enhance biocompatibility and ensure conductivity, by forming a layer of interface‐stable coating (ISC) as a conductive isolation membrane on their surface. For applications with contact requirements, graphite‐like carbon (GLC) coated graphite electrodes are investigated and developed, resulting in an exceptional cell survival rate exceeding 96% under indirect contact conditions, and a relatively high survival rate exceeding 91% under direct contact conditions, both accompanied by significant proliferation. GLC‐coated graphite electrodes are successfully to monitor the dialysate conductivity in a hemodialysis machine and achieve stable monitoring with temperature compensation. The results demonstrate ISC graphite electrodes' potential in biomedical fluid monitoring, with the developed process applicable to other fields. [ABSTRACT FROM AUTHOR]