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With the global proliferation of 5G technology, advancing electronic interconnection technologies has become critically important. The development of high-quality electrolytic copper foils, essential for efficient signal transmission, has garnered considerable attention. To mitigate the "skin effect" that could impair signal transmission and to ensure robust adhesion of electrolytic copper foils to the substrate, it's necessary to roughen the copper foils. This roughening process aims to substantially enhance the peel strength of the copper foils without exceeding the bounds of acceptable roughness. An effective strategy to achieve this involves the use of additives to refine the micro-coarsened surface of the copper foils. In this context, we have explored the impact of additives such as carrageenan, guar gum, and SPS on the surface morphology, roughness, and peel strength of electrolytic copper foils. Three types of additives can improve the performance of micro-roughened copper foil. Through electrochemical tests, it was found that all three types of additives have the effect of increasing cathodic polarization. The adsorption behavior of different additives was studied through theoretical calculations. By hybriding the three additives, two micro-coarsening systems were screened to obtain the lowest roughness and the highest peel strength, respectively. At the same time, the relationship between peel strength and surface area was verified, with the larger surface area resulting in greater peel strength. Finally, the synergistic effect of the three additives on increasing cathodic polarization was verified through chronopotentiometry. [ABSTRACT FROM AUTHOR]

Human multidrug resistance protein 5 (hMRP5) effluxes anticancer and antivirus drugs, driving multidrug resistance. To uncover the mechanism of hMRP5, we determine six distinct cryo-EM structures, revealing an autoinhibitory N-terminal peptide that must dissociate to permit subsequent substrate recruitment. Guided by these molecular insights, we design an inhibitory peptide that could block substrate entry into the transport pathway. We also identify a regulatory motif, comprising a positively charged cluster and hydrophobic patches, within the first nucleotide-binding domain that modulates hMRP5 localization by engaging with membranes. By integrating our structural, biochemical, computational, and cell biological findings, we propose a model for hMRP5 conformational cycling and localization. Overall, this work provides mechanistic understanding of hMRP5 function, while informing future selective hMRP5 inhibitor development. More broadly, this study advances our understanding of the structural dynamics and inhibition of ABC transporters. Human multidrug resistance protein 5 (hMRP5) effluxes anticancer and antivirus drugs, driving multidrug resistance. Here, the authors present cryo-EM structures of hMRP5 in different states, showing that hMRP5 can be autoinhibited by a short peptide from its N-terminal tail, which prevents the entry of substrates into hMRP5's transport pathway. [ABSTRACT FROM AUTHOR]

Myricetin is a kind of natural flavonoid with a variety of physiological activities. Nanosized liposomes made of myricetin have various advantages. Therefore, the preparation of myricetin nanoliposomes by film-ultrasonic dispersion method was studied. Under optimal preparation conditions, the encapsulation efficiency of myricetin liposome suspensions was over 90%, the particle size was 158.1 ± 12.4 nm, the polydispersity index was 0.282, and the zeta potential was − 36.64 mV. After lyophilization and rehydration, myricetin liposomes were stable, the particle size was 171.3 ± 11.6 nm, and the polydispersity index was 0.273. When myricetin liposome suspensions were placed at 4 °C for 72 h, its particle size was maintained at 193.9 ± 10.8 nm, and the polydispersity index was 0.312. The aforementioned results showed that this preparation process has more advantages. In addition, scanning electron microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimeter were used to characterize the nanoliposome. The morphology of the liposomes was nanosized and spherical. Fourier transform infrared spectroscopy exhibited that the myricetin had been successfully loaded into the nanoliposomes. Differential scanning calorimeter suggested that myricetin was dispersed well in the carriers. The 90-day accelerated stability test confirmed that embedding myricetin in nanoliposomes improved its stability. The obtained myricetin nanoliposomes had excellent performance, which provided potential use in pharmaceutical application and functional food. [ABSTRACT FROM AUTHOR]

In order to fabricate copper coatings with excellent brightness, a cationic additive was screened by applying the electrochemical method and the theoretical calculation method. The adsorption-coordination coupling inhibition mechanism was proposed to illustrate the influence of the additive methylene blue (MB). The electrochemical behavior of copper electrodeposition influenced by MB was investigated by cyclic voltammetry and chronoamperometry. The copper electrodeposition under the influence of MB is diffusion-controlled, while the nucleation and growth of coating are 3D diffusion-controlled instantaneous nucleation processes. The electroplating process was optimized and bright copper coating can be obtained at wide range of current density according to SEM analysis and AFM analysis. The XRD was used to study the phase structure under the influence of current density and (1 1 1) surface is obtained preferentially with the increase of current density. The mean grain size is within 100 nm according to Scherrer's formula, illustrating that nanocrystalline copper coating is obtained. [ABSTRACT FROM AUTHOR]

In order to realize high-quality through-hole (TH) interconnection with high aspect ratio, the mechanism of reverse pulse on TH electrodeposition process was systematically studied. In this paper, the mechanism of sodium thiazolinyl dithio propane sulfonate (SH110) was studied by electrochemical methods and molecular dynamics (MD) simulation. Under different direction of electric fields, the binding energies of SH110 and on Cu (111) are different. The behavior changes of SH110 in reverse pulse process under different convection conditions and the competitive adsorption relationship with other additives were explained. In addition, the results of TH electroplating verify the possibility of the additive system in practical application. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of carbon dioxide is an attractive and challenging strategy to solve the problems of renewable energy storage and carbon neutral. However, activity, selectivity, and stability of present developing catalysts for production of C2H4 are not as high as required for practical applications. Herein, we report dezincified copper nanowires (pre-CuZn-CuNW) derived from an electrodeposited CuZn alloy by a wet chemical method for electrochemical reduction of carbon dioxide to C2H4. Compared with pre-Cu-CuNW (the copper nanowires derived from a bulk Cu), the pre-CuZn-CuNW significantly enhances the catalytic activity and the selectivity for C2H4. The partial normalized current density of the pre-CuZn-CuNW for production of C2H4 increases to 183 mA∙cm−2, which is about twice relative to pre-Cu-CuNW. The faradaic efficiency (FE) of the pre-CuZn-CuNW for C2H4 can be maintained over 46% for 24 h during carbon dioxide reduction reaction. The improved catalytic performance can be attributed to the formation of a special nanowire structure with larger electrochemical active surface area and higher intrinsic activity of the pre-CuZn-CuNW during the dealloying process. [ABSTRACT FROM AUTHOR]

With the gradual development of high density and high integration of printed circuit board (PCB), the electroplating technology of PCB has been widely paid attention by researchers and enterprises, among which the through-hole (TH) electroplating of PCB is the key to realize the multi-layer interconnection. Many researches improve the electroplating quality of TH by optimizing the technological conditions. In this paper, the development trend and challenges of TH electroplating are introduced. In addition, the research mechanism of TH electroplating as well as the influence of additives and periodic pulse reverse electroplating on TH electroplating are also introduced. In addition, the methods of studying the electroplating process through numerical model and optimizing the electroplating process are analyzed and summarized. By adding additives to the bath and deeply studying the mechanism of TH electroplating through numerical simulation, the technological parameters of TH interconnection were optimized. The research status of TH electroplating was reviewed. The deposition mechanism was studied by theoretical calculation method and the electrode process was changed by using additives to improve the quality of TH electroplating. [ABSTRACT FROM AUTHOR]

Gel polymer electrolytes are one of the candidates for solid electrolytes to solve safety issues and improve the energy density of solid-state lithium batteries. Gel polymer electrolyte has high ionic conductivity at room temperature (~ 10−3 S cm−1), but its mechanical properties are poor. Herein, we prepared a series of composite gel polymer electrolytes by N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide, poly(vinylidene fluoride-hexafluoropropylene), LiTFSI, and various inorganic fillers. The addition of 5 wt% TiO2 can not only increase the ionic conductivity of gel polymer electrolytes but also improve the mechanical properties of gel polymer electrolytes. Besides, as a semiconductor, the TiO2 has safety risk when uses in composite gel polymer electrolyte. TiO2-ILGPE safety is investigated by cyclic voltammetry and battery performance. Additionally, TiO2-ILGPE displays a perfect flame-retarding ability, and TiO2 would not be reduced by the lithium metal anode. [ABSTRACT FROM AUTHOR]

As a crucial material for fabrication of lithium-ion battery current collector, the properties of electrodeposited copper foil are closely related to the battery performances. How to improve its properties is thus of great importance for battery design and manufacturing. In this paper, we reported a novel composite additive, consisting of collagen, glycerol, hydroxyethyl cellulose, and sodium polydisulfide dipropane sulfonate, for electrodeposition of high-quality copper foil from conventional acid copper sulfate bath. Meanwhile, a pulse superimposed on direct current was used during the preparation process of copper foil. It was demonstrated that the additive could improve the foil's performances, through changing the kinetic parameters of copper electrodeposition in sulfate bath. The optimized bath has a higher allowable current density during superimposed current electrodeposition, in contrast to the situation in direct current electrodeposition. This may then lead to an increase in deposition rate of copper foil, and a further improvement in surface roughness, grain size, residual stress, as well as elongation. Specially, the superimposed current offers a number of adjustable parameters for modulating copper foil's properties in a wide range. [ABSTRACT FROM AUTHOR]

Highlights: A promising solar-powered environmentally friendly process for the synthesis and application of catalysts for hydrogen evolution reaction has been proposed. A delicate NiCo(OH)x-CoyW catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by electrochemical etching process. The excellent catalytic effect of NiCo(OH)x-CoyW for the hydrogen evolution reaction was systematically investigated through various physical and electrochemical analyses.To achieve high efficiency of water electrolysis to produce hydrogen (H2), developing non-noble metal-based catalysts with considerable performance have been considered as a crucial strategy, which is correlated with both the interphase properties and multi-metal synergistic effects. Herein, as a proof of concept, a delicate NiCo(OH)x-CoyW catalyst with a bush-like heterostructure was realized via gas-template-assisted electrodeposition, followed by an electrochemical etching-growth process, which ensured a high active area and fast gas release kinetics for a superior hydrogen evolution reaction, with an overpotential of 21 and 139 mV at 10 and 500 mA cm−2, respectively. Physical and electrochemical analyses demonstrated that the synergistic effect of the NiCo(OH)x/CoyW heterogeneous interface resulted in favorable electron redistribution and faster electron transfer efficiency. The amorphous NiCo(OH)x strengthened the water dissociation step, and metal phase of CoW provided sufficient sites for moderate H immediate adsorption/H2 desorption. In addition, NiCo(OH)x-CoyW exhibited desirable urea oxidation reaction activity for matching H2 generation with a low voltage of 1.51 V at 50 mA cm−2. More importantly, the synthesis and testing of the NiCo(OH)x-CoyW catalyst in this study were all solar-powered, suggesting a promising environmentally friendly process for practical applications. [ABSTRACT FROM AUTHOR]

For improving performance of silicon anode in lithium ion batteries, a two-step preparation method was applied for synthesis of silicon carbon powder. The first step was to prepare Si/Ni composite powder by magnesiothermic reduction reaction in which Tetraethoxysilane (TEOS) was silicon source and NiCl2∙6H2O was nickel source. The second step was to prepare silicon carbon in which triethylene glycol was carbon source and reduced by nickel catalyzed reactions on the surface of Si/Ni composite particles. Strawberry-like porous silicon attached with graphene-like carbon was found in the sample of Si-C powder treated by 1 M FeCl3 and 5 wt.% HF. Charge/discharge performance of anode materials were measured in button cells. The highest discharge specific capacity of Si-C powder can reach to 1275 mAh g−1, but the cycle performance was not as good as Si/Ni composite powder. At the 50th cycle, the discharge specific capacity of Si/Ni composite powders and Si-C powders were 415 mAh g−1 and 395 mAh g−1, respectively. [ABSTRACT FROM AUTHOR]

Due to the excellent intrinsic activity of platinum, developing a Pt-based oxygen reduction catalyst with both high performance and low loading is highly desirable but still challenging. How to improve the utilization of platinum-based materials has become one of the most critical issues. Herein, a synthesis strategy using the 5,5-dimethylhydantoin (DMH) as complexing agent is designed to synthesize the Pt catalyst via pulse electrodeposition. On the one hand, the platinum nanoparticles prepared by electrodeposition are exposed on the surface of support materials, which effectively avoids performance degradation caused by the coverage of binder and support. On the other hand, the strong coordination affinity between DMH and platinum ions significantly inhibits the electrodeposition process, resulting in a smaller size of platinum nanoparticles. The effect of plating composition and pulse plating parameters on the Pt/KB catalyst activity for oxygen reduction reaction (ORR) has been investigated. The deposited Pt nanoparticles show a face-centered cubic (fcc) crystal structure with a size ranging from 3 to 10 nm. The optimized Pt/KB catalyst exhibits an enhanced activity (i.e., a half-wave potential of 0.906 V) and stability in the acidic media, even with lower loading of platinum. Moreover, the vital role of the DMH in the pulse electrodeposition process is further verified by using linear sweep voltammetry and cyclic voltammetry. [ABSTRACT FROM AUTHOR]

Long polar fimbria (LPF) is one of the few fimbrial adhesins of enterohemorrhagic Escherichia coli (E. coli) O157:H7 associated with colonization on host intestine, and both two types of LPF (including LPF1 and LPF2) play essential roles during the bacterial infection process. Though the fimbriae had been well studied in intestinal pathogenic E. coli strains, new evidences from our research revealed that it might be the key virulence for bovine mastitis pathogenic E. coli (MPEC) as well. This article summarizes the current knowledge on the LPF in E. coli, focusing on its genetic characteristics, prevalence, expression regulation, and adherence mechanism in different pathotypes of E. coli strains. [ABSTRACT FROM AUTHOR]

Lamellar tin deposits were prepared by galvanostatical electroplating from the aqueous acidic-sulfate bath, with gelatin and benzalacetone dissolved in ethanol (A) as additive, and their morphologies were investigated by scanning electron microscopy. Cathodic polarization curves revealed that the absorbability of A on the cathode surface was higher than that of gelatin. X-ray diffraction analysis indicated preferred orientations of tin growth led to the formation of lamellar structure and distortion of tin lattice. The growth mechanism of lamellar tin was also discussed. [ABSTRACT FROM AUTHOR]

Magnetron sputtered permalloy films are treated by wet chemical etchings with acid etchant as well as fluorine based reactive ion etch (RIE). Upon these treatments, the resistivity and coercivity of the permalloy film increase is within 10 %. No significant increase observed with prolonged etching time. The effective magnetization change of the permalloy films are within 5 % post the treatments. Atomic force microscope (AFM) and transmission electron microscope (TEM) are used to study the surface and interface evolution of permalloy film upon etching. The small impact on the electrical and magnetic properties of permalloy films can be correlated with the surface oxide protecting layer formation during the etch. Consequently, sputtered NiFe is a safe material to expose to these etching processes for write pole shield application. [ABSTRACT FROM AUTHOR]

Taurine (Tau) is reported to have a key role in the regulation of the innate immune response and thus reduce tissue damage induced by bacterial infection. In this study, the effects of Tau on a rat model of mastitis induced by Streptococcus uberis ( S. uberis) and the changes of T regulatory cells (Tregs) were assessed. Starting on gestation day 14 and continuing until parturition, 100 mg/kg of taurine (group TS) or an equal volume of physiological saline (group CS) was administered daily, per os. Seventy-two hours after parturition, rats were infused with approximately 100 cfu of S. uberis into each of two mammary glands. The results showed that the resultant inflammation, evidenced by swelling, secretory epithelial cell degeneration, increased adipose tissue and neutrophil (PMN) infiltration were evident in mammary tissue following injection with S. uberis. Pre-treatment with Tau attenuated these morphologic changes, the expression of interleukin (IL)-2, interferon (INF)-γ mRNA, myeloperoxidase (MPO) activity and N-acetyl- β-D-glucosaminidase (NAGase) in mammary tissue. The percentages of Foxp3 + CD25 + CD4 +/lymphocytes (Tregs) were dramatically increased after the S. uberis challenge. Significant differences ( P < 0.05) were observed at 24, and 72 h post S. uberis - injection (PI) in CS. Pre-treatment further increased the percentage of Tregs and a significant difference between CS and TS ( P < 0.05) was apparent at 24 h PI. Our data indicate that in rats, Tau can be used to regulate the immune response following infection by S. uberis and consequently prevent mammary tissue damage by increasing Tregs. [ABSTRACT FROM AUTHOR]

Embryonic stem (ES) cells are pluripotent cells that can self-renew or differentiate into many cell types. A unique network of transcription factors and signalling molecules are essential for maintaining this capability. Here, we report that a spalt family member, Sall4, is required for the pluripotency of ES cells. Similarly to Oct4, a reduction in Sall4 levels in mouse ES cells results in respecification, under the appropriate culture conditions, of ES cells to the trophoblast lineage. Sall4 regulates transcription of Pou5f1 which encodes Oct4. Sall4 binds to the highly conserved regulatory region of the Pou5f1 distal enhancer and activates Pou5f1 expression in vivo and in vitro. Microinjection of Sall4 small interfering (si) RNA into mouse zygotes resulted in reduction of Sall4 and Oct4 mRNAs in preimplantation embryos and significant expansion of Cdx2 expression into the inner cell mass. These results demonstrate that Sall4 is a transcriptional activator of Pou5f1 and has a critical role in the maintenance of ES cell pluripotency by modulating Oct4 expression. The data also indicates that Sall4 is important for early embryonic cell-fate decisions. [ABSTRACT FROM AUTHOR]

SnO2/graphene composite with superior cycle performance and high reversible capacity was prepared by a one-step microwave-hydrothermal method using a microwave reaction system. The SnO2/graphene composite was characterized by X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy, scanning electron microscope, X-ray photoelectron spectroscopy, transmission electron microscopy and high resolution transmission electron microscopy. The size of SnO2 grains deposited on graphene sheets is less than 3.5 nm. The SnO2/graphene composite exhibits high capacity and excellent electrochemical performance in lithium-ion batteries. The first discharge and charge capacities at a current density of 100 mA g−1 are 2213 and 1402 mA h g−1 with coulomb efficiencies of 63.35%. The discharge specific capacities remains 1359, 1228, 1090 and 1005 mA h g−1 after 100 cycles at current densities of 100, 300, 500 and 700 mA g−1, respectively. Even at a high current density of 1000 mA g−1, the first discharge and charge capacities are 1502 and 876 mA h g−1, and the discharge specific capacities remains 1057 and 677 mA h g−1 after 420 and 1000 cycles, respectively. The SnO2/graphene composite demonstrates a stable cycle performance and high reversible capacity for lithium storage. [ABSTRACT FROM AUTHOR]

An erratum is presented concerning the article "MicroRNAs to Nanog, Oct4 and Sox2 coding regions modulate embryonic stem cell differentiation," which was published in the 2008 volume 455 issue.