Catalytic asymmetric synthesis of planar-chiral dianthranilides via (Dynamic) kinetic resolution.

Chirality constitutes an inherent attribute of nature. The catalytic asymmetric synthesis of molecules with central, axial, and helical chirality is a topic of intense interest and is becoming a mature field of research. However, due to the difficulty in synthesis and the lack of a prototype, less attention has been given to planar chirality arising from the destruction of symmetry on a single planar ring. Herein, we report the catalytic asymmetric synthesis of planar-chiral dianthranilides, a unique class of tub-shaped eight-membered cyclic dilactams. This protocol is enabled by cinchona alkaloid-catalyzed (dynamic) kinetic resolution. Under mild conditions, various C2- or C1-symmetric planar-chiral dianthranilides have been readily prepared in high yields with excellent enantioselectivity. These dianthranilides can serve as an addition to the family of planar-chiral molecules. Its synthetic value has been demonstrated by kinetic resolution of racemic amines via acyl transfer, enantiodivergent synthesis of the natural product eupolyphagin, and preliminary antitumor activity studies.

Experimental and Numerical Investigation of Shielding Gas Behaviors in Laser Welding of TC4 Alloy.

Gas protection is a crucial part of quality control in laser welding, especially for titanium alloy, which oxidizes easily at high temperatures. Substantial experiments concerning shielding gas characteristics in the welding process have been implemented. However, the common analysis conducted is simplistic and lacks a theoretical basis. This paper presented an investigation of the shielding gas behaviors based on numerical simulation and a titanium alloy laser welding experiment. The numerical model was established and validated by experiment. Subsequently, the temperature field and gas flow fields were calculated. By combining the two fields, the threshold temperature of gas protection was determined, and the influence of shielding gas parameters on the protection effect was examined. The results revealed that the protection of the high-temperature zone was primarily influenced by the nozzle height, nozzle inner diameter, and nozzle angle, while the plasma suppression effect was mainly correlated with the nozzle inner diameter and gas flow rate. These initial findings provide scientific guidance for the better quality production of laser beam welded components made of not only titanium alloy but also other metallic materials.

Fabrication of Black Silicon Microneedle Arrays for High Drug Loading.

Silicon microneedle (Si-MN) systems are a promising strategy for transdermal drug delivery due to their minimal invasiveness and ease of processing and application. Traditional Si-MN arrays are usually fabricated by using micro-electro-mechanical system (MEMS) processes, which are expensive and not suitable for large-scale manufacturing and applications. In addition, Si-MNs have a smooth surface, making it difficult for them to achieve high-dose drug delivery. Herein, we demonstrate a solid strategy to prepare a novel black silicon microneedle (BSi-MN) patch with ultra-hydrophilic surfaces for high drug loading. The proposed strategy consists of a simple fabrication of plain Si-MNs and a subsequent fabrication of black silicon nanowires. First, plain Si-MNs were prepared via a simple method consisting of laser patterning and alkaline etching. The nanowire structures were then prepared on the surfaces of the plain Si-MNs to form the BSi-MNs through Ag-catalyzed chemical etching. The effects of preparation parameters, including Ag+ and HF concentrations during Ag nanoparticle deposition and [HF/(HF + H2O2)] ratio during Ag-catalyzed chemical etching, on the morphology and properties of the BSi-MNs were investigated in detail. The results show that the final prepared BSi-MN patches exhibit an excellent drug loading capability, more than twice that of plain Si-MN patches with the same area, while maintaining comparable mechanical properties for practical skin piercing applications. Moreover, the BSi-MNs exhibit a certain antimicrobial activity that is expected to prevent bacterial growth and disinfect the affected area when applied to the skin.

Strength Degradation and Fracture Propagation of Repeatedly Immersed Artificial Dam Samples under Uniaxial Cyclic Loading-Unloading.

The use of underground reservoirs is a critical technique for achieving sustainable coal and water resources in many ecologically fragile mines in western China. Concrete samples subject to repeated water immersion and cyclic loading-unloading (CLU) operations were obtained from an underground artificial reservoir dam in Chahasu Colliery to study their strength damage and fracture propagation behavior. The variation in water content of the samples according to immersion times were divided into the rapid growth stage (0-10 h), slow growth stage (10-60 h), and stable stage (>60 h). With an increase in immersion times (IIT), the saturated water content of the coal samples logarithmically increased to 7.02%, and the ultrasonic wave velocity decreased by 10.44%. According to the increasing trend of plastic damage energy density, the total stress-strain curve was divided into four fracture stages. The total energy and elastic energy densities increased nonlinearly with the increase in cycles, whereas the plastic damage energy density first decreased and then increased. The plastic damage energy ratio at the stress peak point of the samples under different sequential times of immersion was 0.18, 0.29, 0.28, 0.58, and 0.61. The initial fracture development and fracture damage thresholds of the samples decreased by 20 and 50% with IIT, respectively. However, the proportion of the fracture closure and initial fracture development thresholds of the samples showed an increasing quadratic trend with IIT. Based on the low ratio of rise time to amplitude and high average frequency, the fracture mode of the samples under repeated water immersion was mainly tensile fracture. Acoustic emission events with energy higher than 104 aJ spread from the center with repeated water immersion. When the CLU was greater than 6, the plastic damage energy of the fitted three-dimensional surface increased nonlinearly with IIT. The energy parameter-plastic damage energy ratio was introduced to help develop a theoretical model for describing the complete stress-strain damage evolution of repeatedly immersed concrete samples under CLU. The paper provides technical references for improving the long-term strength design of concrete artificial dams of underground reservoirs.

Micro-structured P-N junction surfaces: large-scale preparation, antifouling properties, and a synergistic antibacterial mechanism.

Constructing an antifouling surface cost-effectively is vitally important for many applications. Herein, a series of silicon substrates with micro-pyramid structures and p-n junctions were fabricated following a simple industrial processing flow, among which the p+n-Si substrate, fabricated through boron doping of a micro-pyramid structured n-type silicon wafer, exhibited the most pronounced antibacterial performance. Broad-spectrum bactericidal and bacteriostatic activity of p+n-Si under ambient light illumination was observed, with an inhibition ability of 73-100% compared to that of a bare glass against both airborne and contact-transmitted bacteria in the intensive care unit. The synergetic effect of mechanical rupture and electric injury was supposed to be responsible for the potent antibacterial activity. This work proposes a state-of-the-art concept that p-n junctions enhance the anti-infection ability of micro-structured surfaces and provide a promising strategy for fabricating practical antifouling surfaces with a large-size, a facile manufacturing procedure, and gentle working conditions, as well as broad-spectrum and physical antibacterial mechanisms.

Germplasm resources and genetic improvement of Akebia: A new fruit crop in China.

Akebia species, belonging to Lardizabalaceae, are widespread from subtropical to temperate environments of China, Japan, and Korea. All known Akebia species have medicinal and dietary value and have been widely cultivated as a new fruit crop in many areas of China. However, compared with other crop species, the breeding improvement and commercial cultivation of Akebia remain in their infancy. This review systematically introduces the present germplasm resources, geographical distribution, biological characteristics, interspecific and intraspecific cross compatibility, molecular biology, and breeding progress in Akebia species. Akebia plants are widely distributed in Shanxi, Henan, Sichuan, Chongqing, Hunan, Hubei, Jiangxi, Zhejiang, and Fujian provinces of China, and wild Akebia plants exhibit abundant phenotypic and genetic diversity due to their wide range of geographical distribution and high adaptability in different habitats. Interspecific artificial hybridization experiments have been conducted in our Akebia germplasm resources nursery. The results showed that there was no reproductive isolation between Akebia species, and fertile progeny could be produced. The synthesis of knowledge on these species provides insights for the rational development and utilization of these germplasm resources, and can facilitate the development of new breeding lines or varieties for commercial cultivation or production. Finally, perspectives on Akebia breeding research are discussed and conclusions are provided. This review provided breeders with new insights into Akebia domestication and breeding, and we also proposed five basic steps in the domestication of new fruit crops.

The use of biological amniotic membranes in the treatment of recurrent macular holes.

To evaluate the clinical therapeutic effects of a technique in which biological amniotic membranes (bAMs) are used in the treatment of patients with recurrent macular holes. In this prospective nonrandomized case series study, 23 eyes of 23 patients with recurrent macular holes who had already undergone surgery with pars plana vitrectomy with internal limiting membrane peeling were evaluated. In the surgery, a bAM was used to cover the macular area, and C3F8 tamponade was performed on these patients. Phacoemulsification combined with intraocular lens implantation was performed simultaneously in patients who had cataracts. Patients were followed up for at least half a year. The main outcomes were whether the macular hole closed, the morphological changes in the macular graft, the best-corrected visual acuity, intraocular pressure (IOP) and other indicators. In all eyes, the recurrent macular holes were closed. Two cases (8.69%, 2/23) had bAM shifting half a month after surgery, and these patients underwent a second surgery to adjust the position of the bAM and perform C3F8 tamponade. In the 6-month follow-up, 21 patients (91.30%, 21/23) had improved visual acuity (VA), and 2 patients (8.69%, 2/23) had no change in VA. The mean VA increased from 1.73 ± 0.32 before surgery to 1.12 ± 0.42 after surgery (t = 10.63, P = 0.00 < 0.01), and the mean IOP decreased from 22.13 ± 5.56 before surgery to 17.23 ± 1.71 after surgery (t = 5.14, P = 0.00 < 0.01). No serious complications occurred in any of the cases. The technique of using a biological amniotic membrane can be an effective treatment for patients with recurrent macular holes.

Visible light-induced N-radical 5-exo/6-endo cyclization of alkenyl amides: facile access to isoindolinones/isoquinolinones.

An efficient N-centered radical intramolecular cyclization reaction of alkenyl amides induced by visible light was described. In this process, an alkenyl amide underwent 5-exo/6-endo cyclization to selectively yield two critical alkaloid structures, namely isoindolinones and isoquinolinones.

NiMoFe/Cu nanowire core-shell catalysts for high-performance overall water splitting in neutral electrolytes.

A bifunctional NiMoFe/Cu NW core-shell catalyst assembled into a practical solar-driven overall water splitting system leads to an unprecedented solar-to-hydrogen (STH) efficiency of 10.99% in neutral electrolytes, attributed to the synergic combination of a unique 3D self-supported core-shell architecture and rapid electron/mass transfer properties.

Adsorption of organic and inorganic arsenic from aqueous solution: Optimization, characterization and performance of Fe-Mn-Zr ternary magnetic sorbent.

Arsenic is a highly toxic pollutant and exists in inorganic and organic forms in groundwater and industrial wastewater. It is of great importance to reduce the arsenic content to lower levels in the water (e.g., <10 ppb for drinking) in order to minimize risk to humans. In this study, a Fe-Mn-Zr ternary magnetic sorbent was fabricated via precipitation for removal of inorganic and organic arsenate. The synthesis of sorbent was optimized by Taguchi method, which leads to an adsorbent with higher adsorption capacity. The adsorption of As(V) was pH dependent; the optimal removal was achieved at pH 2 and 5 for inorganic and organic As(V), respectively. Contact time of 25 h was sufficient for complete adsorption of both inorganic and organic As(V). The adsorption isotherm study revealed that the adsorbent performed better in sequestration of inorganic As(V) than that of organic As(V); both adsorption followed the Langmuir isotherm with maximum adsorption capacities of 81.3 and 16.98 mg g-1 for inorganic and organic As(V), respectively. The existence of anions in the water had more profound effect on the adsorption of organic As(V) than the inorganic As(V). The co-existing silicate and phosphate ions caused significantly negative impacts on the adsorption of both As(V). Furthermore, the existence of humic acid caused the deterioration of inorganic As(V) removal but showed insignificant impact on the organic As(V) adsorption. The mechanism study demonstrated that ion exchange and complexation played key roles in arsenic removal. This study provides a promising magnetic adsorptive material for simultaneous removal of inorganic and organic As(V).

Heterostructure of core-shell IrCo@IrCoOxas efficient and stable catalysts for oxygen evolution reaction.

Although researches on non-noble metal electrocatalysts have been made some progress recently, their performance in proton exchange membrane water electrolyzer is still incomparable to that of noble-metal-based catalysts. Therefore, it is a more practical way to improve the utilization of precious metals in electrocatalysts for oxygen evolution reaction (OER) in the acidic medium. Herein, nanostructured IrCo@IrCoOxcore-shell electrocatalysts composed of IrCo alloy core and IrCoOxshell were synthesized through a simple colloidally synthesis and calcination method. As expected, the hybrid IrCo-200 NPs with petal-like morphology show the best OER activities in acidic electrolytes. They deliver lower overpotential and better electrocatalytic kinetics than pristine IrCo alloy and commercial Ir/C, reaching a low overpotential (j = 10 mA cm-2) of 259 mV (versus RHE) and a Tafel slope of 59 mV dec-1. The IrCo-200 NPs displayed robust durability with life time of about 55 h in acidic solution under a large current density of 50 mA cm-2. The enhanced electrocatalytic activity may be associated with the unique metal/amorphous metal oxide core-shell heterostructure, allowing the improved charge transferability. Moreover, the *OH-rich amorphous shell functions as the active site for OER and prevents the further dissolution of the metallic core and thus ensures high stability.

The application portfolio empowerment method and ELECTRE-I for optimising the control of ammonia release during the aerobic fermentation process.

Aerobic fermentation composting can transform solid organic waste into biological organic fertiliser, while reducing resource wastage and ecological damage. However, in the composting process, a serious loss of nitrogen occurs, primarily in the form of the release of ammonia gas. The release of ammonia gas not only pollutes the environment, but also diminishes the presence of nutrient elements, resulting in compost products that are lower in quality. Given that many factors influence the release of ammonia gas during the aerobic fermentation process, it is difficult to determine optimal process parameters. In an effort to address this issue, we propose herein a combinational weighting method based on the analytic hierarchy process (AHP) and entropy weighting method to determine the weight of each secondary index. We also establish a parametric optimisation model based on the ammonia release conditions of the ELECTRE-I method that provides a theoretical underpinning and a decision basis for optimising the process parameters that mediate the release of ammonia during the aerobic fermentation process. This method can be widely employed to reduce the release of ammonia gas and may be of significance to the future development of bioengineering-based composting technology.

Conversion therapy from N3 unresectable lung adenocarcinoma to radical surgery: a case report.

Patients with N3 non-small cell lung cancer (NSCLC) have unresectable tumors. Although significant progress has been made in the past decades for such tumors, the average median survival time remains at 10 months. Equally dismal long-term survival rates were reported with the average 5-year-suvival rate at 9%. Here, we report on a case of a patient with locally advanced disease that was treated with conversion therapy using targeted anti-PD-1 immunotherapy with platinum-based chemotherapy. Following this therapeutic regimen, the tumor showed a reversion to pN0 from pN3 and the patient showed a progression free survival time of at least 33 months.

Low-cost and environmentally friendly synthesis of an Al3+ and Mn4+ co-doped Li4Ti5O12 composite with carbon quantum dots as an anode for lithium-ion batteries.

To increase the specific capacity and conductivity of lithium titanate (LTO), low-cost and environmentally friendly carbon quantum dots (CQDs) were used to composite with Al3+ and Mn4+ co-doped Li4Ti5O12 (LTO-Al/Mn) to improve its electrical properties. The Al3+ and Mn4+ were successfully substituted for Ti located at (16d) sites in the LTO and the CQDs formed a composite with LTO-Al/Mn. The specific capacity of the first cycle at 0.1C increased to 296.5 mA h g-1, and the impedance decreased to 16.8 Ω. The specific capacity maintained 236.0 mA h g-1 after 100 cycles.

Visible light driven metal-free intramolecular cyclization: a facile synthesis of 3-position substituted 3,4-dihydroisoquinolin-1(2H)-one.

A visible-light metal-free photocatalytic synthesis of 3-position substituted 3,4-dihydroisoquinolin-1(2H)-one derivatives under mild conditions in moderate to good yields is described. EosinY Na, an organic dye, which is of low cost and has good availability, is used as the photocatalyst. A wide range of substrates are tolerated and the gram-scale reaction can also proceed smoothly. Mechanistic studies indicate that a plausible free radical process is proposed.

Gene Ontology-based function prediction of long non-coding RNAs using bi-random walk.

BACKGROUND: With the development of sequencing technology, more and more long non-coding RNAs (lncRNAs) have been identified. Some lncRNAs have been confirmed that they play an important role in the process of development through the dosage compensation effect, epigenetic regulation, cell differentiation regulation and other aspects. However, the majority of the lncRNAs have not been functionally characterized. Explore the function of lncRNAs and the regulatory network has become a hot research topic currently. METHODS: In the work, a network-based model named BiRWLGO is developed. The ultimate goal is to predict the probable functions for lncRNAs at large scale. The new model starts with building a global network composed of three networks: lncRNA similarity network, lncRNA-protein association network and protein-protein interaction (PPI) network. After that, it utilizes bi-random walk algorithm to explore the similarities between lncRNAs and proteins. Finally, we can annotate an lncRNA with the Gene Ontology (GO) terms according to its neighboring proteins. RESULTS: We compare the performance of BiRWLGO with the state-of-the-art models on a manually annotated lncRNA benchmark with known GO terms. The experimental results assert that BiRWLGO outperforms other methods in terms of both maximum F-measure (Fmax) and coverage. CONCLUSIONS: BiRWLGO is a relatively efficient method to predict the functions of lncRNA. When protein interaction data is integrated, the predictive performance of BiRWLGO gains a great improvement.

Novel human microbe-disease associations inference based on network consistency projection.

Increasing evidence shows that microbes are closely related to various human diseases. Obtaining a comprehensive and detailed understanding of the relationships between microbes and diseases would not only be beneficial to disease prevention, diagnosis and prognosis, but also would lead to the discovery of new drugs. However, because of a lack of data, little effort has been made to predict novel microbe-disease associations. To date, few methods have been proposed to solve the problem. In this study, we developed a new computational model based on network consistency projection to infer novel human microbe-disease associations (NCPHMDA) by integrating Gaussian interaction profile kernel similarity of microbes and diseases, and symptom-based disease similarity. NCPHMDA is a non-parametric and global network based model that combines microbe space projection and disease space projection to achieve the final prediction. Experimental results demonstrated that the integrated space projection of microbes and diseases, and symptom-based disease similarity played roles in the model performance. Cross validation frameworks and case studies further illustrated the superior predictive performance over other methods.

A novel approach for predicting microbe-disease associations by bi-random walk on the heterogeneous network.

Since the microbiome has a significant impact on human health and disease, microbe-disease associations can be utilized as a valuable resource for understanding disease pathogenesis and promoting disease diagnosis and prognosis. Accordingly, it is necessary for researchers to achieve a comprehensive and deep understanding of the associations between microbes and diseases. Nevertheless, to date, little work has been achieved in implementing novel human microbe-disease association prediction models. In this paper, we develop a novel computational model to predict potential microbe-disease associations by bi-random walk on the heterogeneous network (BiRWHMDA). The heterogeneous network was constructed by connecting the microbe similarity network and the disease similarity network via known microbe-disease associations. Microbe similarity and disease similarity were calculated by the Gaussian interaction profile kernel similarity measure; moreover, a logistic function was applied to regulate disease similarity. Additionally, leave-one-out cross validation and 5-fold cross validation were implemented to evaluate the predictive performance of our method; both cross validation methods performed well. The leave-one-out cross validation experiment results illustrate that our method outperforms other previously proposed methods. Furthermore, case studies on asthma and inflammatory bowel disease prove the favorable performance of our method. In conclusion, our method can be considered as an effective computational model for predicting novel microbe-disease associations.

N-Doped nanodots/np(+)-Si photocathodes for efficient photoelectrochemical hydrogen generation.

Carbon nanodots treated with N2-plasma are effective catalysts for solar-driven hydrogen-evolved-reaction on np(+)-Si photocathodes and a support for Pt allowing for the reduction in Pt loading by a factor of about 3.5 while improving the photoelectrochemical activity.

Uptake of arsenate by an alginate-encapsulated magnetic sorbent: process performance and characterization of adsorption chemistry.

Arsenate removal by a calcium alginate-encapsulated magnetic sorbent was studied. The morphology, microstructure, and composition properties of the sorbent were explored using X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). The SEM study demonstrates that there are many protuberances and pores on the sorbent surface; the XRD analysis reveals that the sorbent consists of Fe(3)O(4). The EDX analysis indicates that the adsorption on the surfaces of sorbent is highly location dependent. The interaction characteristics between the arsenic and the functional groups on the sorbent were studied by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). These studies indicate that the lattice oxygen in magnetite and the oxygen in hydroxyl of the calcium alginate play important roles in the sorption of arsenate ions onto the sorbent. More importantly, the XPS analysis demonstrates that the arsenate is reduced to arsenite after its adsorption onto the sorbent. It is proposed that divalent iron and the alcoholic group in alginate provide electrons to arsenate. A conceptual model for the adsorption is proposed to illustrate the mechanisms.