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Metal oxides are promising (photo)electrocatalysts for sustainable energy technologies due to their good activity and abundant resources. Their applications such as photocatalytic water splitting predominantly involve aqueous inter- faces at electrochemical conditions, but in situ probing oxide-water interfaces is proven to be extremely challenging. Here, we present an electrochemical scanning tunneling microscopy (EC-STM) study on the rutile TiO2(110)-water interface, and by tuning surface redox chemistry with careful potential control we are able to obtain high quality images of interfacial structures with atomic details. It is interesting to find that the interfacial water exhibits an unexpected double-row pattern that has never been observed. This finding is confirmed by performing a large scale simulation of a stepped interface model enabled by machine learning accelerated molecular dynamics (MLMD) at ab initio accuracy. Furthermore, we show that this pattern is induced by the steps present on the surface, which can propagate across the terraces by interfacial hydrogen bonds. Our work demonstrates that by combining EC-STM and MLMD we can obtain new atomic details of interfacial structures that are valuable to understand the activity of oxides at realistic conditions.

The quality of perovskite films plays a crucial role in the performance of the corresponding devices. However, the commonly employed perovskite polycrystalline films often contain a high density of defects created during film production and cell operation, including unsaturated coordinated Pb

Staphylococci are mainly found on the skin or in the nose. These bacteria are typically friendly, causing no harm to healthy individuals or resulting in only minor issues that can go away on their own. However, under certain circumstances, staphylococcal bacteria could invade the bloodstream, affect the entire body, and lead to life-threatening problems like septic shock. In addition, antibiotic-resistant Staphylococcus is another issue because of its difficulty in the treatment of infections, such as the notorious methicillin-resistant Staphylococcus aureus (MRSA) which is resistant to most of the currently known antibiotics. Therefore, rapid and accurate diagnosis of Staphylococcus and characterization of the antibiotic resistance profiles are essential in clinical settings for efficient prevention, control, and treatment of the bacteria. This chapter highlights recent advances in the diagnosis of Staphylococci in clinical settings with a focus on the advanced technique of surface-enhanced Raman spectroscopy (SERS), which will provide a framework for the real-world applications of novel diagnostic techniques in medical laboratories via bench-top instruments and at the bedside through point-of-care devices.

The cavity-based X-ray free-electron laser (XFEL) has promise in producing fully coherent pulses with a bandwidth of a few meV and very stable intensity, whereas the currently existing self-amplified spontaneous emission (SASE) XFEL is capable of generating ultra-short pulses with chaotic spectra. In general, a cavity-based XFEL can provide a spectral brightness three orders of magnitude higher than that of the SASE mode, thereby opening a new door for cutting-edge scientific research. With the development of superconducting MHz repetition-rate XFEL facilities such as FLASH, European-XFEL, LCLS-II, and SHINE, practical cavity-based XFEL operations are becoming increasingly achievable. In this study, megahertz cavity enhanced X-ray generation (MING) is proposed based on China’s first hard XFEL facility - SHINE, which we refer to as MING@SHINE.

EC-STM is applied to directly observe structural dynamics during the OER on LaNiO3 epitaxial thin films.

Copper is the most widely used substrate for Li deposition and dissolution in lithium metal anodes, which is complicated by the formation of solid electrolyte interphases (SEIs), whose physical and chemical properties can affect Li deposition and dissolution significantly. However, initial Li nucleation and growth on bare Cu creates Li nuclei that only partially cover the Cu surface so that SEI formation could proceed not only on Li nuclei but also on the bare region of the Cu surface with different kinetics, which may affect the follow-up processes distinctively. In this paper, we employ

Severe aplastic anemia (SAA) is a fatal bone marrow failure disease. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) with a matched sibling donor is the first-line treatment for older SAA patients. However, the number of CD34A 45-year-old male patient with SAA was treated with a sibling-matched allo-HSCT. Due to the low amount of donor CD34This study provides evidence that UCB-derived HSCs have a higher capacity for hematopoietic reconstitution, suggesting that UCB plus an HLA-matched sibling donor is a good alternative for older patients with SAA.

A highly ordered mesoporous nickel sulfides/nitrogen-doped mesoporous carbon (NiSx/NMC, wherein NiSx represents the combination of NiS and Ni3S4, where 1 < x < 4/3) nanohybrid was synthesized by the assistance of a NMC template as an advanced bifunctional electrocatalyst for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The use of NMC as a template improves the electronic conductivity of the catalyst, while the high specific surface area increases the number of active sites and the highly ordered mesoporous structure enables fast mass transfer. As a result, the Ni3S4/NMC catalyst shows a half-wave potential (E1/2) of 0.89 V vs. RHE for the ORR in 0.1 M KOH and a potential of 1.57 V vs. RHE at 10 mA cm−2 (Ej=10) for the OER in 1.0 M KOH. The potential gap ΔE (ΔE = Ej=10 − E1/2) is 0.68 V, which is significantly lower than the 0.8 V for 10 wt% Pt/C + IrO2. The primary Zn–air battery shows a maximum power density of 186 mW cm−2 and an energy density as high as 805 W h kg−1 at 100 mA cm−2. The battery also exhibits favorable long-term cycling behaviour (the polarization voltage increased by only 0.05 V after 300 charge/discharge cycles for 100 h). This work provides an effective strategy for the design of metal–carbon nanohybrid electrocatalysts for low-cost energy storage and conversion devices.

Mechanical properties of solid-electrolyte interphases (SEIs) play pivotal roles in maintaining reversible cycling of Li metal anode. However less attentions have been paid to the integration of kinds of SEIs on Li nuclei, and precise characterization of mechanical properties of SEIs also appear challenging. Herein, we employ combined in-situ atomic force microscope (AFM) based nanoindentation and peak force quantitative nanomechanics (QNM) methods to explore structures, thickness and Young’s moduli of three kinds of SEIs which may appear in “anode-free” Li metal batteries, and correlate mechanical properties with chemical and/or electrochemical origins. Results show that SEIs formed by electrochemical reduction bear conventional double layer structures and are much thicker with smaller Young’s moduli, compared with the inorganic-organic hybrid SEIs formed with involvement of chemical reactions. In-situ AFM monitoring of morphology evolution shows that coexistence of different kinds of SEIs on individual Li nuclei, even with apparently minor differences in thickness and Young’s moduli, could result in breakages of SEI shells upon dissolution of Li nuclei. Our work reveals the importance of integration of kinds of SEIs on Li nuclei and demonstrates the advantage of combined use of nanoindentation and QNM methods in understanding the cause mechanical point of view.

Learning interpretable and interpolatable latent representations has been an emerging research direction, allowing researchers to understand and utilize the derived latent space for further applications such as visual synthesis or recognition. While most existing approaches derive an interpolatable latent space and induces smooth transition in image appearance, it is still not clear how to observe desirable representations which would contain semantic information of interest. In this paper, we aim to learn meaningful representations and simultaneously perform semantic-oriented and visually-smooth interpolation. To this end, we propose an angular triplet-neighbor loss (ATNL) that enables learning a latent representation whose distribution matches the semantic information of interest. With the latent space guided by ATNL, we further utilize spherical semantic interpolation for generating semantic warping of images, allowing synthesis of desirable visual data. Experiments on MNIST and CMU Multi-PIE datasets qualitatively and quantitatively verify the effectiveness of our method., ICPR 2020

To investigate the prognostic evaluation value of neutrophil-lymphocyte ratio (NLR) in patients with newly diagnosed angioimmunoblastic T cell lymphoma (AITL).Clinical data of 39 patients with newly diagnosed AITL in our hospital from March 2010 to August 2018 were colleated and retrospective analyzied, and the relationship between NLR before treatment and the prognosis of AITL patients was analyzed.Among 39 AITL patients, the median value of NCR was 5.43. Based on the cut-off value (5.43), all the patients were divided into 2 groups: high NLR group (5.43, n=20) and a low NLR group (＜5.43, n=19). The total effective rate of treatment was lower in the high NLR group as compered with low NLR group (P=0.041). Univariate analysis showed that, age ＞60 years old, extranodal involvement＞1 as well as high NLR were the independent risk factors that affected overall survival (OS) in newly diagnosed AITL patients. Multivariate Cox analysis showed that extranodal involvement＞1 and high NLR were the independent risk factors that affected OS in newly diagnosed AITL patients.The NLR may be an independent prognostic factor in patients with newly diagnosed AITL. High NLR associated with poor prognosis.中性粒细胞/淋巴细胞比值在初诊血管免疫母细胞性T细胞淋巴瘤患者预后分析中的价值.探讨外周血中性粒细胞/淋巴细胞比值（NLR）在初诊血管免疫母细胞性T细胞淋巴瘤（AITL）患者预后评估中的价值.回顾性分析2010年3月至2018年8月在皖南医学院第一附属医院收治的AITL初诊患者临床资料39例，分析治疗前NLR与AITL患者预后的关系.39例AITL患者初诊NLR中位数为5.43，以此中位值为临界值，将AITL患者分成高NLR组（NLR≥5.43，20例）和低NLR组（NLR＜5.43，19例）。与低NLR患者相比，高NLR组患者治疗总有效率更低（P=0.041）。单因素分析结果显示，年龄＞60岁、结外受累部位2个及以上及高NLR是影响患者总生存的不良预后因素。Cox多因素分析结果显示，结外受累部位2个及以上和高NLR是影响患者预后的独立危险因素.外周血NLR水平是影响初诊AITL患者的预后因素，NLR升高提示患者预后不良.

Land cover classification aims at classifying each pixel in a satellite image into a particular land cover category, which can be regarded as a multi-class semantic segmentation task. In this paper, we propose a deep aggregation network for solving this task, which extracts and combines multi-layer features during the segmentation process. In particular, we introduce soft semantic labels and graph-based fine tuning in our proposed network for improving the segmentation performance. In our experiments, we demonstrate that our network performs favorably against state-of-the-art models on the dataset of DeepGlobe Satellite Challenge, while our ablation study further verifies the effectiveness of our proposed network architecture.

An electrochemical method is presented for fabricating cobalt thin films for single-molecule electrical transport measurements. These films are electroplated in an aqueous electrolyte, but the crucial stages of electrochemical reduction to remove surface oxide and adsorption of alkane(di)thiol target molecules under electrochemical control to form self-assembled monolayers which protect the oxide-free cobalt surface are carried out in an ionic liquid. This approach yields monolayers on Co that are of comparable quality to those formed on Au by standard self-assembly protocols, as assessed by electrochemical methods and surface infrared spectroscopy. Using an adapted scanning tunneling microscopy (STM) method, we have determined the single-molecule conductance of cobalt/1,8-octanedithiol/cobalt junctions by employing a monolayer on cobalt and a cobalt STM tip in an ionic liquid environment and have compared the results with those of experiments using gold electrodes as a control. These cobalt substrates could therefore have future application in organic spintronic devices such as magnetic tunnel junctions.

Aroma significantly contributes to flavor, which directly affects the commercial quality of strawberries. The strawberry aroma is complex as many kinds of volatile compounds are found in strawberries. In this review, we describe the current knowledge of the constituents and of the biosynthesis of strawberry volatile compounds, and the effect of postharvest treatments on aroma profiles. The characteristic strawberry volatile compounds consist of furanones, such as 2,5-dimethyl-4-hydroxy-3(2H)-furanone and 4-methoxy-2,5-dimethyl-3(2H)-furanone; esters, including ethyl butanoate, ethyl hexanoate, methyl butanoate, and methyl hexanoate; sulfur compounds such as methanethiol, and terpenoids including linalool and nerolidol. As for postharvest treatment, the present review discusses the overview of aroma volatiles in response to temperature, atmosphere, and exogenous hormones, as well as other treatments including ozone, edible coating, and ultraviolet radiation. The future prospects for strawberry volatile biosynthesis and metabolism are also presented. © 2018 Society of Chemical Industry.

Titania nanoparticles were successfully synthesized through an easily controlled and simple autothermal gelation process. Effects of H2O2 concentrations, solvent quantity and dissolving temperature were investigated in detail. DSC–TGA and XRD analysis showed that the synthesized TiO2 nanoparticles were in anatase phase at 400°C and in rutile phase at 650°C. TEM image indicated that the titania nanoparticles were uniform and approximately spherical, the average grain size of the product was about 20 nm.

Learning concepts in chemistry through recitations often makes learners unable to comprehend the structure of chemical compounds. Therefore, the study aims to develop an educational game Valence Bond© for chemical bond learning, which combines with scientific visualization and provides learners with mechanisms for manipulation. The study also explores learners' learning effectiveness in the game, their technology acceptance and flow. This game helps learners' chemical bond learning through the mechanism of scientific visualization and the challenge from tower defense game. Based on our empirical evaluation, learners in this study have high flow and technology acceptance for this game. Learners with more prior knowledge are also more easily involved in the game. Finally, learners' learning effectiveness reaches significant difference after using the game.

The immobilization of thiol-derivatized DNA on a Au (111) single crystal surface by self-assembly has been investigated by electrochemical scanning tunneling microscopy (EC-STM). Continuous potential-dependent orientation changes of double-stranded oligodeoxynucleotides (ODN) have been observed in a certain potential range from 200 to 600 mV (versus SCE). It is suggested that the DNA duplexes stand straight on the gold surface at potentials negative of the potential of zero charge (pzc) and then lay down on the surface when the potential shifts positively. These results are in agreement with the expectation based on the Coulombic interaction consideration between negatively charged DNA helices and gold surface. As the applied potential shifts positively, the surface charge changes from negative to positive, that is, the Coulombic force between negatively charged DNA helices and gold surfaces changes from repulsion to attraction. However, for the single-stranded oligodeoxynucleotides, no distinct changes in the surface structure were observed with the applied potential.

Self-assembled monolayers (SAMs) of alkanols (1-C(N)H(2N+1)OH) with varying carbon-chain lengths (N = 10-30) have been systematically studied by means of scanning tunneling microscopy (STM) at the interfaces between alkanol solutions (or liquids) and Au(111) surfaces. The carbon skeletons were found to lie flat on the surfaces. This orientation is consistent with SAMs of alkanols on highly oriented pyrolytic graphite (HOPG) and MoS2 surfaces, and also with alkanes on reconstructed Au(111) surfaces. This result differs from a prior report, which claimed that 1-decanol molecules (N = 10) stood on their ends with the OH polar groups facing the gold substrate. Compared to alkanes, the replacement of one terminal CH3 group with an OH group introduces new bonding features for alkanols owing to the feasibility of forming hydrogen bonds. While SAMs of long-chain alkanols (N > 18) resemble those of alkanes, in which the aliphatic chains make a greater contribution, hydrogen bonding plays a more important role in the formation of SAMs of short-chain alkanols. Thus, in addition to the titled lamellar structure, a herringbone-like structure, seldom seen in SAMs of alkanes, is dominant in alkanol SAMs for values of N < 18. The odd-even effect present in alkane SAMs is also present in alkanol SAMs. Thus, the odd N alkanols (alkanols with an odd number of carbon atoms) adopt perpendicular lamellar structures owing to the favorable interactions of the CH3 terminal groups, similar to the result observed for odd alkanes. In contrast to alkanes on Au(111) surfaces, for which no SAMs on an unreconstructed gold substrate were observed, alkanols are capable of forming SAMs on either the reconstructed or the unreconstructed gold surfaces. Structural models for the packing of alkanol molecules on Au(111) surfaces have been proposed, which successfully explain these experimental observations.

Biological materials with hierarchically laminated structures usually exhibit a good synergy between strength and fracture toughness. Here, we show that a bio-inspired (polyelectrolyte (PE)/TiO2)4 nanolayered composite with a thickness ratio of TiO2 and amorphous PE layers of about 1.1 has been prepared successfully on Si substrates by layer-by-layer self-assembly and chemical bath deposition methods. Microstructures of the nanolayered composite were investigated by scanning electron microscopy, secondary ion mass spectroscopy, and high-resolution transmission microscopy. Mechanical performance of the composite was characterized by instrumented indentation. The composite consisting of 17.9-nm-thick nanocrystalline TiO2 and 16.4-nm-thick amorphous PE layers has a strength of about 245 MPa, which is close to that of shells, while the fracture toughness of the composite, KIC = 1.62 ± 0.30 MPa · m1/2, is evidently higher than that of the bulk TiO2. A possible strategy to build the composite at nanoscale for high mechanical performance was addressed.

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