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Introduction and hypothesis: There were few data about the long-term outcomes of bio-compatible patches for pelvic organ prolapse (POP). The efficacy of poly (L-lactide-co-caprolactone) blended with fibrinogen [P(LLA-CL)/Fg] bio-patches were investigated for anterior vaginal wall prolapse treatment in a 6-year follow-up. Methods: The P(LLA-CL)/Fg bio-patch was fabricated through electrospinning. Nineteen patients with symptomatic anterior prolapse (Pelvic Organ Prolapse Quantification [POP-Q] stage ≥ 2) were treated with anterior pelvic reconstruction surgery using a P(LLA-CL)/Fg bio-patch and were followed up at 1, 2, 3, 6 months, and 6 years. The primary outcome was objective anatomical cure (anterior POP-Q stage ≤ 1). Secondary outcomes included complications, MRI evaluation, and scores of the Pelvic Floor Impact Questionnaire-7 (PFIQ-7) and the Pelvic Floor Distress Inventory-20 (PFDI-20). Results: The micro-morphology of the bio-patch resembled the extracellular matrix, which was suitable for the growth of fibroblasts. Sixteen (84.2%) patients were finally assessed, with a mean follow-up of 6.08 ± 0.18 years. The cure rate without anterior prolapse recurrence was 93.8% at 6 years. Compared with baseline, the POP-Q measurements of Aa, Ba, and C points and scores of PFIQ-7 and PFDI-20 manifested significant differences at all times (all p < 0.05). One (5.26%) case of bio-patch-related infection, 1 (5.26%) case of urinary retention, and no exposures and erosion occurred. MRI evaluation showed that the bio-patch gradually degraded to fragments at 1 month and was completely absorbed at 3 months. Conclusions: Among long-term follow-ups, anterior pelvic reconstruction surgery with a P(LLA-CL)/Fg bio-patch demonstrated significant improvements in anatomical correction of anterior pelvic prolapse and pelvic function without severe morbidity. [ABSTRACT FROM AUTHOR]

Cell cycle studies in plants and algae are highly dependent on reliable methods for detecting cellular DNA replication. With its short growth cycle and ease of genetic transformation, Phaeodactylum tricornutum is an important model organism for the study of pennate diatoms. Here we explored two different methods to detect the cell cycle of P. tricornutum, one using SYBR‐green I to via flow cytometry, and the other using EdU labeling to observe cell cycle changes under fluorescence microscopy. Both EdU labeling fluorescence microscopy and SYBR‐green I staining flow cytometry accurately indicated that the cells of P. tricornutum enter the G2/M phase after 12 h of light exposure. The results indicate that SYBR Green I was an adequate detection method for nuclear DNA quantitation in cells of P. tricornutum using a flow cytometer and without RNase A treatment. In addition, EdU can be applied to P. tricornutum to reliably detect cell proliferation. Besides, Mg‐ProtoIX was able to reverse the cell cycle division inhibition of P. tricornutum and allow the nuclear DNA replication to proceed normally. Taken together, the photoperiodic division time point was clearly identified, which sheds light on the regulation of cell division mechanism in P. tricornutum. [ABSTRACT FROM AUTHOR]

The computation offloading problem in mobile edge computing (MEC) has received a lot of attention, but service caching is also a research topic that cannot be ignored in MEC. Due to the limited resources available on the Edge Server (ES), a wise computation offloading and service caching policy must be formulated in order to maximize system offload efficiency. In this paper, a many-objective joint optimization computation offloading and service caching model (MaJOCOSC) is designed. The model takes into account the limited computing and storage resources of ES, the delay and energy consumption constraints of different types of tasks, and multiple processing modes of user tasks, and sets delay, energy consumption, task hit service rate, service cache balancing, and load balancing as the five optimization objectives of MaJOCOSC. Meanwhile, a non-dominated sorting genetic algorithm (NSGAIII-ASF&WD) based on achievement scalar function (ASF) and the k-nearest neighbor weighted distance mating selection strategy is proposed for better solving the model. The ASF ensures that the given strategy performs well for each objective value, and the k-nearest neighbor weighted distance provides the user with a diversity of strategies. Simulation results show that NSGAIII-ASF&WD can obtain better objective values when solving the model compared with other many-objective evolutionary algorithms, and a suitable computation offloading and service caching strategy is obtained. [ABSTRACT FROM AUTHOR]

Herein, we have developed a novel single-molecular probe (NORP) for selective and accurate determination of NTR in living cells. It was discovered that up-regulation of endogenous NTR occurred in response to hypoxic stimulation, and there was a dependence between the NTR levels and the degree of hypoxia. [ABSTRACT FROM AUTHOR]

Highlights: Fe3+, Co2+, H3BTC, and collagen peptide are used to achieve a one-step assembly of stable FeCo-MOG/CP by manipulating the complexation effect and solution polarity. By optimizing pyrolysis, two kinds of nitrogen-doped carbon aerogels loaded with virus-shaped and nanospherical magnetic particles are obtained. FeCo/Fe3O4/NC and FeCo/NC aerogels exhibit excellent electromagnetic wave absorbing and radar stealth performances. Metal–organic gel (MOG) derived composites are promising multi-functional materials due to their alterable composition, identifiable chemical homogeneity, tunable shape, and porous structure. Herein, stable metal–organic hydrogels are prepared by regulating the complexation effect, solution polarity and curing speed. Meanwhile, collagen peptide is used to facilitate the fabrication of a porous aerogel with excellent physical properties as well as the homogeneous dispersion of magnetic particles during calcination. Subsequently, two kinds of heterometallic magnetic coupling systems are obtained through the application of Kirkendall effect. FeCo/nitrogen-doped carbon (NC) aerogel demonstrates an ultra-strong microwave absorption of − 85 dB at an ultra-low loading of 5%. After reducing the time taken by atom shifting, a FeCo/Fe3O4/NC aerogel containing virus-shaped particles is obtained, which achieves an ultra-broad absorption of 7.44 GHz at an ultra-thin thickness of 1.59 mm due to the coupling effect offered by dual-soft-magnetic particles. Furthermore, both aerogels show excellent thermal insulation property, and their outstanding radar stealth performances in J-20 aircraft are confirmed by computer simulation technology. The formation mechanism of MOG is also discussed along with the thermal insulation and electromagnetic wave absorption mechanism of the aerogels, which will enable the development and application of novel and lightweight stealth coatings. [ABSTRACT FROM AUTHOR]

The corrosion behavior and surface conductivity of type 446 stainless steel were investigated in the simulated cathode environment of proton exchange membrane fuel cell with 0.0005 M H2SO4 + 0.1 ppm F− solution at 80 °C under different polarization potentials by using electrochemical measurement methods, X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectroscopy (ICP-OES). The 446 stainless steel passivates spontaneously in the simulated environment. The current density and interface contact resistance (ICR) enlarge slightly with increasing the anodic polarization potential in the passive region. As the potential changes from 0.7 to 1.5 V vs. SCE, the current density and ICR increase markedly due to the occurrence of transpassivation, secondary passivation, and oxygen evolution. The ICR values are larger by about 24 mΩ cm2 after the polarization above 0.7 V vs. SCE. The polarization potential shifts from the passive region to oxygen evolution region, resulting in higher oxidized Fe and Mo contents in the product film on specimen surface and relatively more release of alloying constituents (especially Cr and Mo) into the solution. These are mainly responsible for the degradation of corrosion and surface conductivity properties. [ABSTRACT FROM AUTHOR]

The studies on the preparation of high-quality and long-wavelength-emitting silicon quantum dots and their application in biochemical detections have attracted increasing interests from researchers. In particular, the exploration of the effect of SiQDs and their complex in antibacterial and inhibition of biofilm areas, is of great significance to human health. This paper reports the fast synthesis of green-fluorescent SiQDs (TC-SiQDs, QYs=25%, Em=520 nm) with the synergistic effect of thiourea and catechol through microwave-assisted one-step hydrothermal route. Based on internal filtering effect, TC-SiQDs were then successfully employed as selective probes to detect vitamin B 12 , with detection range at 0.05–30 μM and limit of detection at 50 nM. Thanks to the excellent biocompatibility and fluorescence property of TC-SiQDs, they have been applied in bacterial imaging. The prepared TC-SiQDs also exhibit certain antibacterial ability with their minimum inhibitory concentration (MIC) against Staphylococcus aureus (S. aureus) at 250 μg/mL, but their inhibitory ability is effective to the growth of S. aureus biofilm only when the concentration reaches 1.3 mg/mL. TC-SiQDs-lysozyme complex were prepared, based on the effects of singlet oxygen, charge effect and lysozyme hydrolysis of peptidoglycan in the cell wall, the complex exhibits high inhibiting activity with MIC against S. aureus at 10 μg/mL and exhibits superior inhibition activity against S. aureus biofilm at a concentration of only 62.5 μg/mL. This paper provides good theoretical and practical basis for the synthesis of long-wavelength emission and ultra-bright SiQDs and their applications in detection, antibacterial and biofilm growth inhibition, and other biomedical fields. [Display omitted] • The green-emitting TC-SiQDs have been prepared through synergistic effect. • The sensitive detection of VB 12 has been realized based on inner filter effect. • TC-SiQDs exhibit broad-spectrum antibacterial and bacterial imaging abilities. • TC-SiQDs-LZM shows strong antibacterial ability to certain bacteria and biofilm. [ABSTRACT FROM AUTHOR]

In this work, we developed a new organic electrochemical probe, 4-(prop-2-yn-1-yloxy)phenol, for the determination of tyrosinase. The designed probe contained a 4-hydroxybenzyloxy moiety for the specific determination of Tyr and a terminal alkyne group for chemical adsorption onto the electrode surface. The oxidation peak of the phenolic group from Pyyp decreased but increased for o-diphenol or o-quinone generated after the reaction between Tyr and Pyyp. The present sensor demonstrated a good linearity with Tyr activity in a dynamic range of 1.0–30 U mL−1. The limit of detection was as low as 0.28 ± 0.12 U mL−1. Moreover, this sensor demonstrated high selectivity for Tyr determination against metal ions, amino acids, ROS and neurotransmitters due to the specific recognition of Tyr. Finally, the developed sensor with high accuracy, high selectivity and long-term stability was successfully applied for evaluating Tyr activity in normal brain homogenate and brain homogenate with Parkinson's disease. [ABSTRACT FROM AUTHOR]

Water electrolysis is the most clean and high-efficiency technology for production of hydrogen, an ultimate clean energy in future. Highly efficient non-noble electrocatalysts for hydrogen evolution reaction (HER) are desirable for large scale production of hydrogen by water electrolysis. Especially, exposing as many active sites as possible is a vital way to improve activities of the catalysts. Herein, a series of new hydrangea like composite catalysts of ultrathin Mo 2 S 3 nanosheets assembled uprightly and interlacedly on N, S-dual-doped graphitic biocarbon spheres were facilely prepared. The unique structure endowed the catalysts highly exposed edge active sites and prominently high activities for HER. Especially, the optimized catalyst Mo 2 S 3 /NSCS-50 exhibited as low as 106 mV of overpotential at 10 mA/cm2 (denoted as ƞ 10). The catalyst also showed low Tafel slope of 53 mV/dec, low electron transfer resistance of 34 Ω and high stability evidenced by the result that the current density only attenuated 11.7% after 10 h i-t test. The catalyst has shown broad prospect for commercial application in water electrolysis. • New Mo 2 S 3 ultrathin nanosheets based catalysts have been fabricated for HER. • Mo 2 S 3 ultrathin nanosheets assembled uprightly and interlacedly on carbon spheres. • Hydrangea like composite catalysts were formed based on the above assembly. • The unique structure can provide plenty of exposed edge active sites. • The catalysts exhibited prominent activities and high stabilities for HER. [ABSTRACT FROM AUTHOR]

The effect of surface roughness on the interfacial contact resistance (ICR) and the corrosion behavior of 446 stainless steel in simulated anode environments for proton exchange membrane fuel cell (PEMFC) (i.e., 0.5 mol L−1 H2SO4 + 2 ppm F− and 5 × 10−4 mol L−1 H2SO4 + 0.1 ppm F− bubbled with hydrogen gas at 80 °C) was investigated by means of atomic force microscopy, potentiodynamic polarization, electrochemical impedance spectroscopy and ICR test. The surface roughness (Ra) produced by mechanical grinding increases noticeably with the decrease of sandpaper grit size from 1000# to 240#. 446 stainless steel shows the active state under free corrosion conditions in the two test solutions and the passive state at the typical anode working potential of PEMFC after the activation-passivation transition. The corrosion resistance decreases with the increase of roughness in both solutions. The corrosion product films formed in the solution with lower acidity are more protective, leading to the appearance of the diffusion process. The enlargement of surface roughness results in the gradual reduction of ICR, but the acceleration of active and passive dissolutions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 S 4 @Co 3 O 4 /N, S-doped carbon core@shell structural composites were constructed. • Interfacial and structural engineering were comprehensively employed. • Interfacial effect optimizes the adsorption properties of the active sites. • Synergistic effect among the composites can modulate the electron configuration. • The optimal catalyst has excellent OER/ORR performances for metal-air batteries. Herein, a class of Co 3 S 4 @Co 3 O 4 /NSC (N, S-doped carbon) composites with core@shell nanostructures were facilely fabricated through a two-step pyrolysis-oxidation strategy using methyl orange and cobalt chloride as raw materials. By constructing heterointerfaces between different components and controlling the surface oxidation degree, the interfacial and synergistic effects endowed the composited catalysts tailorable and excellent bifunctional electrocatalytic activities on oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). A rechargeable Zn-air battery (ZAB) with the optimized catalyst Co 3 S 4 @Co 3 O 4 /NSC-260-8 as air cathode has shown excellent performance with a high specific capacity of 885 mAh·g Zn −1 and energy density of 948 Wh·kg Zn −1 (at 20 mA·cm−2), which is higher than 836 mAh·g Zn −1 and 929 Wh·kg Zn −1 of the one employing Pt/C (20%) + RuO 2 as air cathode under the same conditions. The catalyst also showed robust stability and no obvious decrease in the voltage was observed after 200 h charging and discharging cycles. This work presents a feasible concept to design and construct heterostructural and multifunctional composite catalysts with heterointerfaces. [ABSTRACT FROM AUTHOR]

• A novel communication-efficient federated recommendation model is proposed. • A many-objective evolutionary method is used to achieve parameter reduction. • Recommended performances and communication cost are optimized simultaneously. The federated recommendation system (FedRS), which is the application of the recommendation system (RS) in federated learning, has been creatively developed as increasing attention has been paid to user privacy protection. However, traditional federated learning consumes excessive communication time and resource, which seriously limits the development of the FedRS. To reduce the communication cost and improve the recommendation performance of FedRS, an improved many-objective federated recommendation model with a novel parameter reduction strategy is proposed in this paper. The model aims to optimize the number of parameters shared between the server and client to improve communication efficiency in the federated process. Optimal parameter selection solutions can be obtained using the many-objective evolutionary algorithm (MaOEA), which can optimize the recommendation accuracy, novelty, diversity, and communication efficiency of FedRS simultaneously. Furthermore, the reference vector guided evolutionary algorithm (RVEA) was adopted to evaluate the proposed model. Experiments were performed on two famous recommendation datasets to examine the superiority of RVEA for the evaluation. The performance results indicated that the proposed model can not only provide accurate, diverse, and novel recommendations for the client, but can also realize efficient communication. [ABSTRACT FROM AUTHOR]

Development of effective non-noble electrocatalysts for hydrogen evolution reaction (HER) is crucial for hydrogen production by water electrolysis. Herein, several composite catalysts of non-stoichiometric Mo 6 S 9.5 films grown on graphene-like N-doped carbon films were prepared and evaluated for HER in 0.5 M H 2 SO 4. The unique structure endowed the catalysts with highly exposed edge active sites, high specific surface area and prominently high activities for HER. The optimized catalyst exhibited a low overpotential of 113 mV at 10 mA/cm2, a low Tafel slope of 64 mV/dec, and a low charge transfer resistance of 40 Ω along with a highly catalytic stability. [Display omitted] • New Mo 6 S 9.5 ultrathin films based catalysts have been fabricated for HER. • Mo 6 S 9.5 ultrathin films were grown on graphene-like N-doped carbon films. • The unique structure can provide plenty of exposed edge active sites. • The carbon films can improve the conductivity of the catalysts. • The catalysts exhibited prominent activities and high stabilities for HER. [ABSTRACT FROM AUTHOR]

Highly efficient multifunctional earth-abundant elements based electrocatalysts are key important for development of clean energy transformation technologies, such as metal-air batteries, fuel cells and water electrolysis. Herein, composite catalysts of N-doped carbon wrapping Co x P hollow spheres have been successfully prepared by pyrolysis of precursors from self-assembly of cobalt salt, terephthalic acid and PVP followed by carbonization and phosphatization in the presence of sodium hypophosphite. The resulted composites showed high specific surface areas, pore volumes and nitrogen contents, especially more than 47% of pyridinic-N. The electrocatalytic activity tests showed that the optimized Co x P-NC-420 sample exhibited superior multifunctional performances and high stabilities for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) under alkaline conditions. A low overpotential of 125/273 mV (at 10 mA cm−2) and Tafel slope of 66/81 mV dec−1 was obtained for HER and OER, respectively. As for ORR, as high as 0.860 V of half-wave potential was obtained, which is even 36 mV higher than that of Pt/C (20%). The catalyst also exhibited high practical performances on water electrolysis and Zn−air battery. Only 1.61 V of cell voltage was needed to reach 10 mA cm−2 for water electrolysis, and 1.374 V of open-circuit potential and 52 mW cm−2 of power density were obtained for Zn−air battery, which was 16 mW cm−2 higher than that of Pt/C (20%). Moreover, a highly effcient self-driven water electrolyzer has been designed with Co x P-NC-420 as both anode and cathode catalyst, powered by two-series-connected Co x P-NC-420-based Zn–air batteries. This work provides a new strategy for fabrication of non-precious multifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]