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An efficient method to construct 4-aryl-substituted β-carbolines from indole-2-methyl-α-aminoketones via a TMSOTf-promoted annulation reaction was reported. High yield along with wide substrate scope and functional group tolerance make this reaction applicable to build various highly potential bioactive β-carboline derivatives.

The selective functionalization of trifluoromethyl groups through C–F cleavage poses a significant challenge due to the high bond energy of the C(sp3)–F bonds. Herein, we present dihydroacridine derivatives as photocatalysts that can functionalize the C–F bond of trifluoromethyl groups with various alkenes under mild conditions. Mechanistic studies and DFT calculations revealed that upon irradiation, the dihydroacridine derivatives exhibit high reducibility and function as photocatalysts for reductive defluorination. This process involves a sequential single-electron transfer mechanism. This research provides valuable insights into the properties of dihydroacridine derivatives as photocatalysts, highlighting the importance of maintaining a planar conformation and a large conjugated system for optimal catalytic activity. These findings facilitate the efficient catalytic reduction of inert chemical bonds.

Inflammatory bowel disease (IBD), consisting of Crohn’s disease and ulcerative colitis, is recognized across the world, though Canada has among the highest burdens of IBD in the world. The Canadian Gastro-Intestinal Epidemiology Consortium (CanGIEC) led a six-province study that demonstrated the compounding prevalence of IBD in Canada from 400 per 100,000 in 2002 to 636 per 100,000 in 2014. The prevalence in 2023 is estimated at 825 per 100,000, meaning that over 320,000 people in Canada are living with IBD. Prevalence is forecasted to rise by 2.44% per year such that 1.1% of the population, 470,000 Canadians, will live with IBD by 2035. The overall incidence of IBD in 2023 is 30 per 100,000 person-years, indicating that over 11,000 Canadians will be newly diagnosed with IBD in 2023. Incidence is forecasted to rise by 0.58% per year up to 32.1 per 100,000 by 2035. The rising incidence of IBD is propelled by pediatric-onset IBD, which is rising by 1.23% per year from 15.6 per 100,000 in 2023 to 18.0 per 100,000 in 2035. In contrast, incidence rates among adults and seniors are relatively stable. Understanding the determinates of IBD has expanded through prospective cohort studies such as the Crohn’s and Colitis Canada Genetic, Environmental, Microbial (CCC-GEM) project. Consensus recommendations towards diet, lifestyle, behavioural and environmental modifications have been proposed by international organizations with the goal of optimizing disease control and ultimately preventing the development of IBD. Despite these efforts, Canadian healthcare systems will need to prepare for the rising number of people living with IBD.Inflammatory bowel disease (IBD) is a disease that causes the intestines to inflame. IBD is something that is found in every country around the world. We have the highest number of people with IBD in the world compared to the total population. In 2002, one in every 250 (119,000) Canadians had IBD. In 2023, one in every 121 (320,000) Canadians has IBD. By 2035, one in every 91 (470,000) Canadians will have IBD. Roughly 11,000 Canadians will develop IBD in 2023. Rates of children developing IBD are rising. The rates of adults developing IBD are not changing. The rates of seniors developing IBD are also not changing. New research looks for better ways to care for IBD. New research also looks for ways to prevent IBD. One such project is Crohn’s and Colitis Canada Genetic, Environmental, Microbial project. This research suggests diet and lifestyle changes to improve the lives of people with IBD. The same changes may help reduce the number of people who develop IBD.

Polyhydroxyalkanoates (PHAs) are a family of natural microbial biopolyesters with the same basic chemical structure and diverse side chain groups. Based on their excellent biodegradability, biocompatibility, thermoplastic properties and diversity, PHAs are highly promising medical biomaterials and elements of medical devices for applications in tissue engineering and drug delivery. However, due to the high cost of biotechnological production, most PHAs have yet to be applied in the clinic and have only been studied at laboratory scale. This review focuses on the biosynthesis, diversity, physical properties, biodegradability and biosafety of PHAs. We also discuss optimization strategies for improved microbial production of commercial PHAs vianovel synthetic biology tools. Moreover, we also systematically summarize various medical devices based on PHAs and related design approaches for medical applications, including tissue repair and drug delivery. The main degradation product of PHAs, 3-hydroxybutyrate (3HB), is recognized as a new functional molecule for cancer therapy and immune regulation. Although PHAs still account for only a small percentage of medical polymers, up-and-coming novel medical PHA devices will enter the clinical translation stage in the next few years.

There are several treatment options for patients with concomitant carotid and coronary artery disease, and it is difficult to identify an optimal treatment strategy that has consensus. Here, we performed a meta-analysis to compare the early and long-term outcomes of staged and synchronous carotid endarterectomy and coronary artery bypass grafting approaches.

Differently to most chemically synthesized medical materials, polyhydroxyalkanoates (PHAs) are intracellular carbon and energy storage granules, which is a family of natural bio‐polymers synthesized by microorganism's materials. Due to excellent biocompatibility reasonable biodegradability and versatile material difference, PHAs are well medical biomaterials candidates for applications in tissue engineering and drug delivery, including commercial PHB, PHBV, PHBHHx, PHBVHHx, P34HB and few uncommercial PHAs. Electrospinning nanofibers with the size of 10–10,000 nm can improve the mechanical properties and decrease the crystallinity of PHA, meanwhile simulate the structure and function of native extracellular matrix of cells. Hence, PHAs electrospinning nanofibers as engineered scaffolds have been widely used for tissue engineering scaffolds in cardiovascular, vascular, nerve, bone, cartilage and skin; also, as carriers for application in drug delivery system. In this review, we highlight the extraction and properties of medical PHAs from natural or engineered microorganism, and microstructure, current manufacturing techniques and medical applications of electrospinning nanofibers of PHAs. Moreover, the current challenges and prospects of PHAs electrospinning nanofibers are discussed rationally, providing an insight into developing vibrant fields of PHAs electrospinning nanofibers‐based biomedicine.

Two different ruthenium content (0.5%, 1.0%) of WC - (W, Ti, Ta) C - Co cemented carbide were prepared by conventional cemented carbide production process. The results showed that adding ruthenium powder can improve the microstructure of alloy compared with excluding ruthenium carbide. The microstructure of alloy with ruthenium addition had uniform structure with less coarse grain.The addition of ruthenium could obviously promote the transverse rupture strength of WC - (W, Ti, Ta) C-Co cemented carbide, and when the adding amount was 1.0%, transverse rupture strength increased by 30%. The addition of ruthenium slightly increased the hardness of the alloy. The results of Scanning electron microscopy and spectrum analysis showed that ruthenium mainly existed in the bonding phase Co. The cutting test showed that the alloy with Ru had better wear resistance.

Aim:We performed a meta-analysis to systematically assess the efficacy and safety of intravenous tranexamic acid in revision total hip arthroplasty. Method:Potential academic articles were identified from Cochrane Library, Medline, PubMed, EMBASE, ScienceDirect and other databases. The time range we retrieved from was that from the inception of electronic databases to February 2019. Gray studies were identified from the references of included literature reports. STATA version 11.0 was used to analyze the pooled data. Results:A total of eight articles were involved in our study. The overall participants of tranexamic acid (TXA) group were 3533, whereas it was 11,007 in the control group. Our meta-analysis showed that TXA is preferable for revision total hip arthroplasty because of its lower value of hemoglobin reduction (weighted mean difference = -1.277–1.405; 95% CI: -1.996 to -0.559; p < 0.001), the rate of blood transfusion (odds ratio: 0.233; 95% CI: 0.129–0.422; p < 0.001) and the number of red blood cell units transfused (weighted mean difference = -0.978; 95% CI = -1.631 to -0.324; p = 0.003). However, there was no difference in calculated blood loss (p = 0.075), operation duration (p = 0.569) and venous thromboembolism complications (p = 0.338). Conclusion:Based on available evidence, use of intravenous TXA for patients undergoing revision arthroplasty may reduce hemoglobin reduction, number of red blood cell units transfused and blood transfusion rate without increasing the risk of venous thromboembolism and length of operation duration. Given the relevant possible biases in our study, adequately powered and better-designed studies with long-term follow-up are required to reach a firmer conclusion.

•The safety of Saussurea involucrataliquid tonic for postpartum medication was evaluated for the first time.•The pharmacokinetic characteristics and milk distribution of main components of Saussurea involucrataliquid tonic were conducted.•The quantitative method for detecting the main components of Saussurea involucrataliquid tonic in the matrix of milk by LC-MS/MS was established.

Aim:The purpose of this study was to conduct a meta-analysis to systematically compare the clinical outcomes between knee barbed sutures (KBS) and knee traditional sutures (KTS) for wound closure in total knee arthroplasty (TKA). Method:This study retrieved potential academic articles comparing the clinical outcomes between KBS and KTS in TKA from the MEDLINE database, the PubMed database, the EMBASE database and the Cochrane Library. The reference articles for the identified studies were carefully reviewed to ensure that all available documents were represented in the study. Results:A total of 14 articles (eight randomized controlled trials [RCTs], six non-RCTs) were involved in our study. The overall participants of barbed Sutures group were 1255, whereas it was 1247 in the traditional sutures. Our meta-analysis showed that KBS is preferable for wound closure of TKA as its shorter lower total cost (weighted mean difference [WMD] = -276.281, 95% CI = -480.281 to -72.280; p = 0.008) and wound closure time (WMD = -4.895,95% CI = -6.105 to -3.685; p < 0.001). However, there was no difference in any complications (p = 0.572), wound complications (p = 0.550), superficial infection (p = 0.918), deep infection (p = 0.654), wound dehiscence (p = 0.649), suture abscess (p = 0.939), arthrofibrosis (p = 0.970), needle sticks (p = 0.158), suture breakage (p = 0.371) and knee society scores (KSS; p = 0.073). Conclusion:The use of KBS in TKA is associated with significantly shortened wound closure times and total closure cost without increased risk of intraoperative needle sticks and suture breakage and postoperative incision complications. Given the relevant possible biases in our study, adequately powered and more RCTs with long-term follow-up are needed to compare the efficacy and safety between KBS and KTS.

Due to the structural advantages displayed by Metal–Organic Frameworks (MOFs), integrating Valence Tautomerism (VT) systems within MOFs could be an effective strategy in order to break through the constraints of the traditional ones. Herein, we report the first successful integration of a VT system into a MOF termed VT-MOF-1. The structural characteristics of VT-MOF-1, such as dinuclear cobalt-catechol clusters and solvent-accessible pores, are both innovative and novel, potentially yielding new vitality within VT field. In addition, VT-MOF-1exhibits specific behaviors responsive to temperature and different solvent molecules as n-butanol, tert-butanol, and isopropyl alcohol. The entropy values and configurations of the solvent molecules might be responsible for the tunable sensing behaviors.

The adsorption mechanism and desorption properties of volatile organic compounds (VOCs) in a zeolitic imidazolate framework (ZIF-7) were studied by on-line thermal desorption-gas chromatography (TD-GC), and a high efficiency method for determination of harmful indoor gas levels has been developed. The loading volume, loading flow rate and desorption temperature were optimized. Additionally, ZIF-7 has been proved to be an effective adsorbent and its adsorption performance is superior to that of commercial Tenax TA and activated carbon. It has been proved that ZIF-7 is an ideal adsorbent for VOCs. It was suggested that there are hydrophobic interactions, π–π stacking effects, “gate-opening” effects and molecular size effects between adsorbates and ZIF-7. Therefore, the developed ZIF-7-based TD-GC method offered an excellent performance with a detection limit of 1.22–2.38 ng (S/N = 3), a quantification limit of 4.05–7.94 ng (S/N = 10), and a good linearity (R2= 0.99), and relative standard deviation values (RSD, n= 5) were found to be in the range of 1.69–7.97%, and tube-to-tube reproducibility for three parallel tubes was 8.01%.

A series of tensile tests, Charpy impact tests, optical microscopy observations, and field emission-scanning electron microscopy examinations, were carried out to investigate the mechanical properties and microstructural evolution of 20Cr32Ni1Nb steel. Experimental results indicate that the as-cast microstructure of the steel typically consists of a supersaturated solid solution of austenite matrix with a network of interdendritic primary carbides (NbC and M23C6). In the ex-service samples, large amounts of secondary carbides precipitate within austenite matrix. Besides the growth and coarsening of NbC and M23C6carbides during service condition, the Ni-Nb silicides known as G-phase (Ni16Nb6Si7) are formed at the interdendritic boundaries. The microstructural evolution results in the degradation of the mechanical properties of the ex-service steel. In addition, the precipitate rate of G-phase, depending in part on Si content, varies greatly for the 20Cr32Ni1Nb steel, which plays a key role in the long-term microstructural stability of the steel. Based on the X-ray diffraction data, time–temperature–transformation curve for the steel is obtained from the aged specimens.

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For the need of simulation research of technical support and obtain basic rush repair data of certain ground-to-air electrical equipment in battlefield condition, this paper studies on the simulation for damage of certain electrical power equipment in battlefield. It analyzes threat mechanisms and basic damage theories of power unit and compiles simulation procedure adopting Monte Carlo method. By simulation, it can analyze vulnerability and distributing of damage parts for electrical power equipment. All this provides reference for rush repair and instruct to defend in battlefield condition.

We demonstrated a model to realize the growth of indium-silver alloy nanocrystals in borosilicate glass by sol-gel method. The presence of spherical indium-silver alloy nanoparticles with 5 nm average grain size and finely dispersed form in borosilicate glass was confirmed by transmission electron microscopy imaging. Reduction of indium-silver ions to indium-silver alloy neutral nanoparticles was revealed through X-ray powder diffraction and X-ray photoelectron spectra. Remarkably, Indium-silver alloy nanocrystal-borosilicate glass exhibited fluorescence at around 423 nm.

A novel new algorithm of path planning is proposed for the robot path planning based on the local data map in the robot autonomous navigation. The algorithm is used to search for the local optimal path from the current position of the robot to the target according to the known sensor data. If the robot cannot reach the target directly, the temporary target point which the robot can reach will be set up according to the optimal path. The algorithm is effective under the complicated unknown environment and moving obstacle situation which fast searching speed, it can be adapted into the practical applications and the multi-robot harmony easily. The simulation result shows that this method can provide a better planning path by comparing with the traditional planning algorithms such as artificial potential field and wall-following

The low cerium oxygen-storage materials of Ce-Zr-Mn composite oxide were prepared by co-precipitation method. The materials were characterized by XRD,BET, OSC and so on. The results show that the precursor is prepared using ammonia as the precipitant at pH=10-13, T≥20℃. The precursor is calcined to form a fresh oxygen-storage materials at 700 ℃ for 5h. It has single crystalline phase -the solid solution Ce 0.45 Zr0.45-x Mn x Y 0.1 O 1.95 ,which has the cube structure of ZrO2 and contains Mn,Y. Phase structure in the materials is stable in the aging process.The addition of Mn in the oxygen-storage materials contributes to raise oxygen-storage performance of the materials. The materials has the better oxygen-storage performance and heat stability when Mn content in the materials is 0.03.

Wind farms with vanadium battery energy storage system are recognized and welcomed. Against the phenomenon of current distribution unreasonable while vanadium batteries are directly paralleled, a control strategy of vanadium battery parallel based on the state of charge (SOC) is proposed. The current control formula is given in this paper. Vanadium batteries are paralleled to adjust the power grid at the exit of wind farms by the bidirectional DC/DC converter. A wind farm model with vanadium battery energy system is simulated on MATLAB/Simulink. The simulation results show that this system can adjust the power grid of wind farms and achieve the goal that the charging and discharging of vanadium batteries are determined by their SOC, avoiding the overcharge or over-discharge.

It is difficult to finish fully and professional testing about frequency converter sets when it was broken or repaired. Aimed at this problem, monitoring system for frequency converter sets is designed. Its hardware circuit is based on IPC platform and PCI bus and software platform is based on Visual Basic and VI (Virtual instrument) technology. It can finish controlling the work status and checking voltage, power etc. and temperature of key parts real-time about the set. Simultaneously it can give an alarm when the status is abnormal. Its results has characteristics of high reliability, high speed and intuitionistic. So it can improve efficiency of test system maximum and save repair expenditure. The system helps for improving reliability of gas turbo-generator set and power quality.

In order to study the juice cooling process after sterilization to obtain the accurate process and reduce the energy used in the cooling, the orange juice in can high temperature short time (HTST) sterilization process was calculated. The maximum temperature of juice in can was defined as 60℃. By using FLUENT, a kind of software which combines hydrodynamics, mathematics and computer technology, we were able to put different fluids into analog computation and numerical experiment to solve problems related to hydrodynamics. Orange juice cooling numerical experiment after HTST sterilization was carried out. The optimization cooling process was obtained: 20℃(293K),14 minutes;15℃(288K),13 minutes; 10℃(283K) ,13minutes; 5℃(278K), 12minutes and 0℃(273K), 12minutes. Using Carnot efficiency in Reverse Carnot cycle, the energy consumption was: 288W, 325W, 348W, 391W, 417W in accordance. And in the result, the optimized process was : 20℃(293K),12 minutes.

The surfaces of carbon black were modified by nitric acid oxidation. The surface structures of the original and oxidized carbon black were investigated by means of FT-IR and XPS, respectively. Furthermore, the oxidized carbon black and distilled water were mixed to form the self-dispersal nanometer carbon black pigment. The particle size distribution and dispersion stability of the carbon black pigment were investigated by means of particle-size analyzer and spectrometer, respectively. The results showed that some highly marked hydrophilic character functional groups on carbon black surfaces were increased greatly by nitric acid oxidation.

The 2D axisymmetric, real gas model was developed to calculate the ejector in the ejector cooling system. The calculation of the real gas model occupies more computer resources, but its result can be more authentic. The CFD model was validated with available experimental data. Predictions at the operating conditions in the ejector cooling system were discussed. The aim of the prediction is to obtain the ejector performance in the non-design condition and variable operating condition. There is an optimum evaporator condition te=20℃ (Pe=0.65bar) with the giving geometry parameters. In the calculation range, when te increase, the entrainment ratio would increase, and the system mechanical COP would also increase. In the paper, the cause of the result was analyzed using the CFD technique. The ejector entrainment ratio was affected by the operation condition and the ejector structure in the same time.

L-Cystine was successfully used as a novel kind of sulfur source to synthesize the nanostructure of ribbon-like Sb2S3. The nanoribbons were usually tens of micronmeters in length, typically 100-300 nm in width. The nanostructure of ribbon-like Sb2S3 were examined using diverse techniques including X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected-area electron diffraction, and high-resolution TEM.

The work functions of LnB6(Ln = Pr, Nd, and Gd) at (100) plane are systematically studied by first‐principles calculation based on density functional theory. It reveals that the work function of LnB6at (100) plane obeys the relation of Φ(PrB6) < Φ(NdB6) < Φ(GdB6). The high‐quality CexLayPryNd0.05Gd0.05B6(x= 0.5, y= 0.2 or x= 0.6, y= 0.15 or x= 0.7, y= 0.1) single crystals are successfully prepared by the optical float‐zone technique. The crystal quality and emission properties of single crystals are characterized by rotating target X‐ray diffraction, X‐ray single‐crystal diffraction, X‐ray Laue diffraction, and the thermal electron emission measurements. The results present that the as‐grown single crystals are of high quality and lower work function than single crystal CeB6. The maximum emission current density of 60.69 A cm−2obtained at 1873 K under the applied voltage of 4000 V belongs to the Ce0.5La0.2Pr0.2Nd0.05Gd0.05B6single crystal with (100) surface. The preparation, crystalline qualities, and thermionic emission properties of single crystalCexLayPryNd0.05Gd0.05B6(x= 0.5, y= 0.2 or x= 0.6, y= 0.15 or x= 0.7, y = 0.1) are reported. The optimized emission properties of Jmax= 60.69 A cm−2and Ф= 2.62 eV for Ce0.5La0.2Pr0.2Nd0.05Gd0.05B6single crystal are superior over CeB6single crystal. It is proved doping rare earth elements can reduce the work function and enhance the thermionic emission performance.