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Hydrogen fuel cell vehicles have always been regarded as the main direction for developing new energy vehicles in the future due to their advantages of zero emission, high cruising range, and strong environmental adaptability. Currently, although the related technologies have gradually matured, there are still many factors hindering its development. One of the main reasons is that the price of hydrogen fuel increases the cost of using vehicles, which puts it at a competitive disadvantage compared with traditional fuel vehicles and pure electric vehicles. Herein, we summarize the recent development status of hydrogen fuel cell vehicles at home and abroad, and analyze the cost and sustainability brought by the latest scientific research progress to the hydrogen production industry, which is derived from basic research on electrocatalysts used in industrial electrocatalytic water splitting with an alkaline electrolyte. Finally, the development of hydrogen fuel cell vehicles was analyzed and prospected, which is one of the main application fields of hydrogen in the future.

Biofilm formation is easily found in patients suffered from ventilator-associated pneumonia (VAP) in neonatal intensive care unit (NICU) and makes the VAP infections not only harder to be treated but easier to relapse. In order to find some novel ways to inhibit biofilm formation, this study describe a previously unrecognized role for the human umbilical cord mesenchymal stem cells (hUCMSCs). In addition to multiple differentiation, hUCMSCs have the ability to prevent the biofilms formation in vitro by secreting antibacterial peptides (LL-37 and hBD-2). This occurred while P. aeruginosa PA27853 and hUCMSCs were cocultured, and the filtrated medium, which was the supernatant containing antibacterial peptides (5.9 ng/ml of LL-37, 1.77 ng/ml of hBD-2), and inhibited the growth of the bacterial biofilm on the surface of tracheal tube (2.5#, for preterm infant). Using microarrays, we were able to demonstrate that the antibacterial peptides from hUCMSC affected biofilm formation by downregulating the gene-encoded polysaccharide biosynthesis protein. In addition, in order to find out the most suitable concentration of hUCMSCs, P. aeruginosa was cocultured with eight-level concentrations of hUCMSCs, and we found that the concentration of LL-37 was positively correlated with the concentration of hUCMSCs. Meanwhile, the concentration of LL-37 became stable while the hUCMSC concentration reaches higher than 5 × 10 6 cells / ml . But the concentration of hBD-2 had no significant correlation with hUCMSCs. The collection of these stem cells is not only limited by ethics but also reduces host rejection. This makes it possible to use autologous hUCMSCs to treat neonatal VAP.

Three new alkali-metal manganese fluoride selenates, A2Mn(SeO4)F3 (A = K, Rb, Cs), were prepared through hydrothermal redox reactions. The products consisted of one-dimensional polymeric anionic ∞[Mn(SeO4)F3]2- chains, where the A+ cations are connected by O and/or F atoms to form blocks with two-dimensional layers. A2Mn(SeO4)F3 (A= Rb, Cs) is isostructural with the monoclinic space group P21/c, while K2Mn(SeO4)F3 crystallizes in the orthorhombic space group Pbcn. A2Mn(SeO4)F3 (A = K, Rb, Cs) forms spin chains of Mn3+ with different Mn-F-Mn bridges, which showed canting antiferromagnetic behaviors. Single-crystal magnetic measurements revealed that the magnetic moments of the Mn ions were more canted for larger alkali-metal compounds in an antiferromagnetically ordered state.

The investigation on antibiotic stewardship in neonatal intensive care unit in China is scarce. This study aimed to analyze the effect of a comprehensive 2-year antibiotic stewardship in a level 4 NICU. During this baseline period from October 1st 2017 to October 1st 2019, continuation of empirical antibiotic therapy for ruled-out sepsis courses was beyond 72 h and for pneumonia was more than 7 days. Meropenem or vancomycin was used even if they were not the only bacterial sensitive antibiotics. The intervention period was from October 2nd 2019 to August 23rd 2021. Three areas for quality improvement were targeted in our center: discontinuation of antibiotic use in ruled-out sepsis within 72 h, treatment duration for culture-negative pneumonia less than 7 days, and vancomycin or meropenem was not used unless the cultured bacteria was only susceptible to them. The total antibiotic consumption decreased from 791.1 to 466.3 days of therapy per 1000 patient days from baseline to intervention period. Antibiotics were stopped within 72 h for 47.48% patients with rule-out sepsis and within 7 days for 75.70% patients with pneumonia compared with 11.56% and 37.69% during the baseline period respectively. The prevalence of multi-drug resistance bacteria decreased from 67.20 to 48.90%. The total use rate of meropenem or vancomycin decreased from 7.6 to 1.8%. Our quality improvement approach on antibiotic strategy significantly reduced antibiotic use and prevalence of multi-drug resistance bacteria in our NICU.

Air pollution is a risk factor for increased hospital admissions due to mental disorders, while green spaces have been linked with better mental health. We linked daily hospital admission records from Wuhan's 74 municipal hospitals from 2017 to 2019 with modeled annual average NO

As a critical content of condition-based maintenance (CBM) for mechanical systems, remaining useful life (RUL) prediction of rolling bearing attracts extensive attention to this day. Through mining the bearing degradation rule from operating data, the deep learning method is often used to perform RUL prediction. However, due to the complexity of operating data, it is usually difficult to establish a satisfactory deep learning model for accurate RUL prediction. Thus, a novel convolutional neural network (CNN) prediction method based on similarity feature fusion is proposed. In this paper, the similarity features are extracted based on the correlation between statistical features and time series. After sensitive feature screening, eligible features are applied to develop a health indicator (HI), which can be used to define the bearing failure stages and reduces the complexity of the CNN model. Subsequently, a one-dimensional CNN is established to predict the RUL of bearing, and the HI is utilized to train the prediction model. The proposed approach is verified by FEMTO bearing datasets and IMS bearing datasets. And the experimental results reveal the superiority and effectiveness of the feature fusion-based CNN method in constructing HI and accurate RUL prediction.

To investigate histopathological placental lesions and adverse neonatal outcomes by Pre-eclampsia (PE) with Gestational Diabetes Mellitus (GDM).This was a retrospective cohort study of pregnancies with PE delivered between 1 January 2012 to 1 January 2014. Pregnant women with PE were recruited, and divided into PE with GDM (PE + GDM) group (The (PE + GDM) group was significantly associated with high placenta weight (534.8 ± 124.1 vs 519.3 ± 132.3 g,GDM increased the offspring's complication in pregnancy with PE, the potential mechanism might be that GDM increased the placenta inflammation.

Four transition-metal monofluorophosphates, with a chemical formula of Ba2M2(PO3F)F6 (M = Mn, Co, Ni, and Cu), have been synthesized hydrothermally using phosphoric and fluorophosphoric acids. The ...

Four new alkali metal copper chlor-tellurites, [Cs(NH4)]layer[Cu4Te2O6Cl6]layer (I), [Rb3(NH4)2(OH)0.5]layer[Cu12Te6Cl16.5O18]layer (II), [K(NH4)]layer[Cu4Te2O6Cl6]layer (III) and [NaCl]layer[Cu4Te2O6Cl4]layer (IV), have been synthesized via hydrothermal reactions using mixtures of AF (A = Cs, Rb, K, Na), CuCl2·2H2O, TeO2, and hydrazine monohydrate. They have two-dimensional (2D)-layered [Cu4Te2Cl5+x–yO6]∞ (x = 0, 2/3, 1; y = 0, 1/6) structures that are separated by different layers comprised of various cations and anions, including A+, NH4+ Cl− OH−, etc. The blocks feature S-shaped ∞[Cu2O3Cl3−x] chains linked by TeO3 trigonal pyramids. The magnetic susceptibility shows a broad maximum at 220 K for I and 240 K for III, which is well simulated by using an alternating antiferromagnetic chain model. The J2/J1 ratio within the alternating chain is estimated to be 0.60(1), and the spin gaps are refined to be 152 K for I and 136 K for III.

International audience; Mixed anion compounds AFe3(SeO3)2F6 (A=K, Rb) have been synthesized by hydrothermal reactions. Prior results obtained for the isostructural Cs analog have revealed original 2D-ferrimagnetic (FI) blocks, antiferromagnetically (AFM) ordered around 120 K. Surprisingly, the whole series orders at a nearly constant TN temperature with similar field-induced magnetization steps, despite significant changes of the interlayer thickness. The metamagnetic transition from AFM to FI on oriented single crystals and Cp measurements prove an in-plane easy-magnetic axis confirmed by neutron powder diffraction (NPD). The ferrimagnetic alignment [Fe(1)↑−Fe(2)↓−Fe(1)↑] in each 2D subunit is robust, but the AFM-ordering between them is broken under weak field leaving field-aligned 2D-macrospins, with weak magnetocrystalline anisotropy. DFT+U calculations validate the exchange ratio Jinter/Jintra of 5.10-3 for all compounds and the relatively high TN value is well predicted by a modified random-phase approximation (RPA) like relation, established for Quasi-Low-Dimensional Heisenberg Antiferromagnets. However, our calculations of intralayer magnetic dipole-dipole (MDD) interactions indicate a non-neglectable values and suggest the latter to assist the in-plane spin orientation below TN. At TN, under field a 3D-Heisenberg model was deduced for the AFM →FI transition from the critical behavior using modified Arrott plots.

Compaction is an important standard in evaluating the quality of earth filling work. The EDG, an electrical density gauge, is a new type of fast and nondestructive compaction detection equipment. It is used to test the dry density and water content of the soil by establishing a soil calibration model while the accuracy of measurement is mainly based on the precision of equation of calibration model. In this paper, the factors affecting the accuracy of the soil calibration model were studied by an indoor calibration test, and soil samples were prepared to verify the accuracy of the soil calibration model. The test results showed that the dry density range, water content range, and sample quantity 13 samples of soil had a significant influence on the correlation coefficient (R2) of the equation of the soil calibration model. In addition, when using the calibration model with different sample numbers and sample combinations but similar correlation coefficients to test multiple groups of density and moisture content, there are also differences in the expected value and standard deviation of the error probability curve of the test results. In the engineering practice, the reasonable sample quantity was determined by the applicable range of dry density and water content obtained from the measurement error analysis of the soil calibration model.

Two M

Digital technology is being increasingly designed and employed to support the preservation and restoration of ancient murals. The contributions of digital technologies to this study were planned from the very beginning, as the complexity of this restoration necessitated the design of innovative procedures to manage the restoration and reconstruction processes and to record the details and deformation of the mural. This paper takes the digital restoration of the "maid holding a fan" mural in the Tang Zhaoling Duan Jianbi tomb as an example. In view of the large number and dislocation of mural fragments, the application of digital restoration technology and its achievements in the restoration of this ancient mural are preliminarily explored in combination with high-precision digital information collection and recording. Technical suggestions and details regarding the digital restoration of the mural are put forward to serve as guidance for the preservation and restoration of ancient murals.

International audience; Two M2(SeO3)F2 fluoro-selenites (M = Mn 2+ , Ni 2+) have been synthesized using optimized hydrothermal reactions. Their 3D framework consists of 1D-[MO2F2] 4chains of edge-sharing octahedra with a rare topology of O-O and F-F alternating µ2 bridges. The inter-chain corner sharing connections are assisted by the mixed O vs. F anionic nature and develop a complex set of M-X-M super-exchanges calculated by LDA+U. Their interplay induce prominent in-chain antiferromagnetic frustration while the interchain exchanges are responsible for the cycloidal magnetic structure observed below TN ~21.5 K in the Ni 2+ case. For comparison the Mn 2+ compound develops a nearly collinear spin (canted) ordering below TN ~26 K with ferromagnetic chain-units.

Previous studies on the extraneous water problem (or infiltration/inflow) in sanitary sewer systems assumed that the wastewater flow is mainly composed of foul sewage (FS), groundwater infiltration (GWI) and rainfall-derived inflow and infiltration (RDII). Most existing assessment methods are based on this assumption. In 2018, China initiated the ‘Protection of the Yangtze River Program’, and the two-year research data showed that it was neither the GWI nor the RDII but the direct surface water intrusion (DSWI), which has rarely been reported in literatures, that serves as the main source of the extraneous water in many local sewer systems. The discovery has enriched the understanding of the extraneous water in sewer systems. Meanwhile, it brings new challenges for the assessment of extraneous water. In this study, starting from the analysis of the low influent concentration of chemical oxygen demand (COD) of the wastewater treatment plant in a southeastern city in China, a river water intrusion point was successfully localized and the volume of river water intrusion was quantified by a series of field experiments. The methodology used in this study can also be applied in other areas with DSWI.

Objective. ANGPTL7 is a member of the angiogenin-like protein family. Compared to other members, ANGPTL7 is the least known. Recent studies have explored the relationship between ANGPTL7 and multiple pathological processes and diseases. However, there is no research about ANGPTL7 in neonates. This study was designed to investigate the concentration of ANGPTL7 in cord blood of preterm infants. Method. Singleton infants born in November 2017 to June 2019 in the study hospital were enrolled in the study. Maternal and neonatal clinical data were collected. ANGPTL7 levels in cord blood and serum on the third day after birth were measured by an enzyme-linked immunosorbent assay. Result. A total of 182 infants were enrolled in this study. Patients were categorized into two groups by gestational age (102 preterm, 80 full-term). ANGPTL7 levels in preterm infants were significantly higher than that in full-term babies ( t = 15.4 , P < 0.001 ). In multiple line regression analysis, ANGPTL7 levels independently correlated with gestational age ( β = − 0.556 , P < 0.001 ). There is also no correlation between preterm outcomes and ANGPTL7 levels. Cord blood levels of ANGPTL7 were significantly higher than those in serum on the third day after birth ( t = 13.88 , P < 0.001 ). Conclusion. Cord blood ANGPTL7 levels are higher in preterm infants than full-term babies. The levels are independently influenced by gestational ages and attenuated significantly after birth. The underlying mechanism needs to be further studied.

Four new alkali metal copper chlor-tellurites, [Cs(NH4)]layer[Cu4Te2O6Cl6]layer (I), [Rb3(NH4)2(OH)0.5]layer[Cu12Te6Cl16.5O18]layer (II), [K(NH4)]layer[Cu4Te2O6Cl6]layer (III) and [NaCl]layer[Cu4Te2O6Cl4]layer (IV), have been synthesized via hydrothermal reactions using mixtures of AF (A = Cs, Rb, K, Na), CuCl2·2H2O, TeO2, and hydrazine monohydrate. They have two-dimensional (2D)-layered [Cu4Te2Cl5+x-yO6]∞ (x = 0, 2/3, 1; y = 0, 1/6) structures that are separated by different layers comprised of various cations and anions, including A+, NH4+ Cl- OH-, etc. The blocks feature S-shaped ∞[Cu2O3Cl3-x] chains linked by TeO3 trigonal pyramids. The magnetic susceptibility shows a broad maximum at 220 K for I and 240 K for III, which is well simulated by using an alternating antiferromagnetic chain model. The J2/J1 ratio within the alternating chain is estimated to be 0.60(1), and the spin gaps are refined to be 152 K for I and 136 K for III.

With the popularity of drones and driverless cars, vehicular crowdsensing (VCS) becomes increasingly widely-used by taking advantage of their high-precision sensors and durability in harsh environments. Since abrupt sensing tasks usually cannot be prepared beforehand, we need a generic control logic fit-for-use all tasks which are similar in nature, but different in their own settings like Point-of-Interest (PoI) distributions. The objectives include to simultaneously maximize the data collection amount, geographic fairness, and minimize the energy consumption of all vehicles for all tasks, which usually cannot be explicitly expressed in a closed-form equation, thus not tractable as an optimization problem. In this paper, we propose a deep reinforcement learning (DRL)-based centralized control, distributed execution framework for multi-task-oriented VCS, called "DRL-MTVCS". It includes an asynchronous architecture with spatiotemporal state information modeling, multi-task-oriented value estimates by adaptive normalization, and auxiliary vehicle action exploration by pixel control. We compare with three baselines, and results show that DRL-MTVCS outperforms all others in terms of energy efficiency when varying different numbers of tasks, vehicles, charging stations and sensing range.

Four transition-metal monofluorophosphates, with a chemical formula of Ba

International audience; The new oxofluoride Co15F2(TeO3)14 has been prepared by optimized hydrothermal synthesis involving complex mineralization process. The crystal structure consists of a three-dimensional network of CoO5(O,F) octahedra, distorted CoO5 square pyramids, TeO3 trigonal pyramids and grossly distorted TeO3+3 octahedra, which are linked by sharing corners and edges. The Te(IV) lone pairs are accommodated within novel pyritohedron-shaped [(TeO3)14] 28units. This special framework provides a much larger free space that allows Te atoms to vibrate with large amplitude, which leads to extremely low lattice thermal conductivity. Magnetic susceptibility data for Co15F2(TeO3)14 show antiferromagnetic ordering below 9.6 K with a substantial orbital component to the effective magnetic moment. An S=3/2 honeycomblike spin network was carefully analyzed by experimental techniques and first principles calculation.

A new oxofluoride Co

Two open-framework transition metal fluorophosphates (NH4)M3(PO3F)2(PO2F2)F2 (M = Mn and Co) have been synthesized under fluoride-rich hydrothermal conditions at 493 K. The structure consists of triplets of face-sharing trans-MO4F2 octahedra linked by PO3F groups to form 2D layers. These 2D layers with formula [M3(PO3F)2O2F2]3- in the ab plane are bridged by PO2F2 groups to generate a 3D open framework with 1D channels filled with ammonium cations. The XPS spectra suggested the existence of Mn(ii) and Co(ii) in the corresponding compounds. Further, the XPS F 1s spectra indicated that fluorine anions bridged both the M and P centres. The two compounds feature transition metal layers with a staircase Kagome network. This topology promotes magnetic frustration, which exhibits a canted antiferromagnetic ground state (Tc = 8.0 K for Mn and Tc = 9.2 K for Co).

Two open frameworks fluorophosphates materials (NH4)2M2F2(PO4)(PO3F)OH (M ​= ​Fe and V) have been synthesized via fluoride-rich hydrothermal routes at 493 ​K. The two isostructural compounds revealed three-dimensional (3D) frameworks, composed of trans-MO4F2, cis-MO4F2, trans-MO2F2(OH)2 octahedra, and PO4, PO3F and NH4 tetrahedra. The anionic backbone of (NH4)2M2F2(PO4)(PO3F)OH consists of a series of parallel zigzag [M2F2O7OH] chains cross-connected with each other, bridged by PO4 tetrahedra within two-dimensional (2D) layer, and bridged by PO3F groups vertical to 2D layer. It generates a three 3D open framework. The XPS spectra revealed the valence of Fe and V are III in the corresponding compounds. The isostructural compounds feature transition metal zigzag chains, which promotes robust antiferromagnetic (AFM) interactions in (NH4)2Fe2F2(PO4)(PO3F)OH in contrast to weak AFM in (NH4)2V2F2(PO4)(PO3F)OH.

Projection micro-stereolithography (PμSL) technique has been demonstrated effective in fabricating the micro lattices. However, the complex fabrication process would inevitably yield stochastic geometric defects within the target structure. In this paper, compressive mechanical properties and deformation modes of the micro gyroid cylinder shell structure with defects originated from the PμSL process were examined through experimental test and numerical simulation. Both the synchrotron X-ray tomography (SR-μCT) investigation and interrupted in-situ compression experiment were conducted to study the role of process-induced defects on the mechanical behavior. Testing results indicated that the fabricated thickness value was much larger than the design value, which had a non-negligible effect on the mechanical properties of the gyroid cylinder shell structure. Then, the reconstructed 3D true model was proposed based on the 2D tomography images. Simulation results indicated that the true model predicted results were more consistent with the experimental results when compared with the ideal model.

Inspired by the self-assembly process of biological macromolecules, MnL2n cage-lattices with distinct structural characteristics were proposed. The five cage-lattices of MnL2n family (i.e. M6L12, M12L24, M24L48, M30L60, M60L120) had huge hollow volume and additive manufacturability. The elastic properties and large strain response of the MnL2n cage-lattices were both investigated numerically and experimentally. Numerical results revealed that the M24L48 cage-lattice had obvious advantage in tensile stiffness, but its shear resistance was insufficient. Through the compression experiment on the stainless steel 316 L samples manufactured by selective laser melting, it was found that the Young's modulus of M30L60 and M60L120 cage-lattices were the lowest, while the energy absorption capacities of M30L60 and M60L120 cage-lattices were close to the other cage-lattices owing to the high hardening rate at the macroscopic level. This paper presented a family of novel MnL2n cage-lattice materials with distinct structural characteristics and additive manufacturability, which broadened the design idea of lightweight multifunctional metamaterials.

Malignant peripheral nerve sheath tumor (MPNST) is a rare tumor that can develop on the lining of nerves and within the network of nerve fibers in different organs, and it is commonly found in the head and neck, limbs, and trunk. These tumors can occur in patients of any age. They most commonly occur in adults aged 20 to 50 years; however, fewer cases of this tumor in children have been reported. To date, no neonatal case of MPNST in the nasal cavity has been reported. Here, we report the case of a 4-day-old female newborn who presented with a nasal mass that re-enlarged after surgery and was diagnosed as MPNST of the nasal cavity on the basis of pathological results. This is the first report of MPNST in the nasal cavity of a neonate. Differential diagnosis and treatment of nasal masses have been proposed in the related literature.

Ni is usually used as the catalyst for the CO2 methanation to generate the substitute natural gas (SNG) due to the low cost. However, it often possesses relatively worse low-temperature catalytic activity than the noble metal counterparts. In order to solve this problem, a series of Ca doped Ni based ordered mesoporous materials had been facilely fabricated via the one-pot evaporation induced self-assembly (EISA) strategy and directly used as the catalysts for CO2 methanation. These materials had been systematically characterized by XRD, N2 adsorption-desorption, TEM, SAED, EDS, XPS, H2-TPR, and CO2-TPD measurements. It was discovered that the large specific surface areas (210.7–240.7 m2/g), big pore volumes (0.37–0.46 cm3/g), and narrow pore size distributions (8.3–9.5 nm) of these materials had been successfully retained after 700 °C calcination. In these materials, Ni species were homogenously dispersed among the Al2O3 matrix via the one-pot fabrication strategy and the strong interaction between Ni and mesoporous framework had been formed. Thus, the seriously thermal sintering of the metallic Ni nanoparticles could be successfully inhibited. Hence, they displayed no deactivation after 50 h stability test toward CO2 methanation. More importantly, the doping of the Ca greatly enhanced the surface basicity, which could favor the chemisorption and activation of CO2. As a result, the apparent activation energies of CO2 could be remarkably decreased from 75.2 to 53.6 kJ/mol and the low-temperature catalytic activity had been significantly promoted. Therefore, these Ca doped Ni based ordered mesoporous materials promised potential catalysts for CO2 methanation.