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In this paper, dynamic characteristics of the single-crystal GaN-passivated lateral AlGaN/GaN Schottky barrier diodes (SBDs) treated with proton irradiation were investigated. Radiation-induced changes including idealized Schottky interface and slightly degraded on-resistance (RON) were observed with 10-MeV proton irradiation at fluences of 1014 cm-2. Benefited from the existing negative polarization charges induced at GaN/AlGaN interface, the dynamic on resistance (RON,dyn) showed negligible degradation after a 1000-s-long forward current stress of 50 mA for devices irradiated or not. Furthermore, the normalized RON,dyn increased by only 14% than the initial case after a 100-s-long bias of -600 V for the irradiated devices. The high-performance lateral AlGaN/GaN SBDs with tungsten as anode metal and in-situ single-crystal GaN as passivation layer show a great potential in the harsh radiation environment of space.

Background: The treatment of bone defects remains a clinical challenge. The effect of negative pressure wound therapy (NPWT) on osteogenesis in bone defects has been recognized; however, bone marrow fluid dynamics under negative pressure (NP) remain unknown. In this study, we aimed to examine the marrow fluid mechanics within trabeculae by computational fluid dynamics (CFD), and to verify osteogenic gene expression, osteogenic differentiation to investigate the osteogenic depth under NP.Methods: The human femoral head is scanned using micro-CT to segment the volume of interest (VOI) trabeculae. The VOI trabeculae CFD model simulating the bone marrow cavity is developed by combining the Hypermesh and ANSYS software. The effect of trabecular anisotropy is investigated, and bone regeneration effects are simulated under NP scales of −80, −120, −160, and −200 mmHg. The working distance (WD) is proposed to describe the suction depth of the NP. Finally, gene sequence analysis, cytological experiments including bone mesenchymal stem cells (BMSCs) proliferation and osteogenic differentiation are conducted after the BMSCs are cultured under the same NP scale.Results: The pressure, shear stress on trabeculae, and marrow fluid velocity decrease exponentially with an increase in WD. The hydromechanics of fluid at any WD inside the marrow cavity can be theoretically quantified. The NP scale significantly affects the fluid properties, especially those fluid close to the NP source; however, the effect of the NP scale become marginal as WD deepens. Anisotropy of trabecular structure coupled with the anisotropic hydrodynamic behavior of bone marrow; An NP of −120 mmHg demonstrates the majority of bone formation-related genes, as well as the most effective proliferation and osteogenic differentiation of BMSCs compared to the other NP scales.Conclusion: An NP of −120 mmHg may have the optimal activated ability to promote osteogenesis, but the effective WD may be limited to a certain depth. These findings help improve the understanding of fluid mechanisms behind NPWT in treating bone defects.

In the existing modular joint design and control methods of collaborative robots, the inertia of the manipulator link is large, the dynamic trajectory planning ability is weak, the collision stop safety strategy is dependent, and the adaptability and safety to the changing environment are limited. This paper develops a six-degree-of-freedom lightweight collaborative manipulator with real-time dynamic trajectory planning and active compliance control. Firstly, a novel motor installation, joint transmission, and link design method is put forward to reduce the inertia of the links and improve intrinsic safety. At the same time, to enhance the dynamic operation capability and quick response of the manipulator, a smooth planning of position and orientation under initial/end pose and velocity constraints is proposed. The adaptability to the environment is improved by the active compliance control. Finally, experiments are carried out to verify the effectiveness of the proposed design, planning, and control methods.

Extracorporeal membrane oxygenation (ECMO) is a superior life support technology, commonly employed in critical patients with severe respiratory or hemodynamic failure to provide effective respiratory and circulatory support, which is especially recommended for the treatment of critical neonates. However, the vascular management of neonates with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is still under controversy. Reconstruction or ligation for the right common carotid artery (RCCA) after ECMO is inconclusive. This review summarized the existed studies on hemodynamics and neurological function after vascular ligation or reconstruction hoping to provide better strategies for vessel management in newborns after ECMO. After reconstruction, the right cerebral blood flow can increase immediately, and the normal blood supply can be restored rapidly. But the reconstructed vessel may be occluded and stenotic in long-term follow-ups. Ligation may cause lateralization damage, but there could be no significant effect owing to the establishment of collateral circulation. The completion of the circle of Willis, the congenital anomalies of cerebral or cervical vasculature, the duration of ECMO, and the vascular condition at the site of arterial catheterization should be assessed carefully before making the decision. It is also necessary to follow up on the reconstructed vessel sustainability, and the association between cerebral hemodynamics and neurological function requires further large-scale multi-center studies.

In this paper, it is found that the preferential growth of secondary {117} facets of Bi24O31Br10 into dominant facets would lead to higher photocatalytic activity, although the original main {213} facet has a stronger molecular oxygen adsorption ability, which illustrates that the charge separation efficiency induced by dominant/secondary facet control plays a more important role than that of O2 adsorptive performance in improving activity.

Gas atomization uses a high-speed gas flow to impact alloy melt and crush it into small droplets. During this process, the kinetic energy of the high-speed gas flow is transformed into the surface energy of small droplets, and the droplets are dragged and cooled by the gas. In this study, a FeNiCrBSiC alloy was used to investigate the motion and solidification behavior of alloy droplets during gas atomization. A mathematical model of the cooling and solidification process of droplets is modified and used. The initial velocity of the droplets attributed to the breakup by the high-speed gas flow is considered a factor. The results suggest that the velocity difference between the droplet and the gas is appearing to be smaller, indicating that droplets are more likely to collide with each other; as the velocity difference between the droplet and the gas becomes smaller, the heat transfer coefficient decreases. Thus, the solidification process of the droplet needs a longer flight distance; the relation between the cooling rate and the particle size was determined from measured data and empirical formula and model validation was performed.

The purpose of this investigation was to evaluate the microstructure, high-temperature oxidation behaviour, and hardness of a seal coating under controlled exposures at 750 °C with different exposure times. The results reveal that the main phases in the coating are Ni, FeNi3, and hexagonal BN, with α-Al2O3 peaks appearing after 2-h oxidation. As the exposure time increases, the diffraction peak intensity of α-Al2O3 begins to decrease and Cr2O3 peaks appear after 200 h. After 1000 h, Cr2O3 becomes dominant with only small amounts of α-Al2O3 remaining. The high-temperature oxidation process of the coating includes three stages: the fast stage, transition stage, and slow stage. The oxidation rate is constant in each stage, and in the fast stage and slow stages with values of 7.59 × 10−4 and 8.37 × 10−5 mg2·cm−4·s−1, respectively. Initially, α-Al2O3 forms near the pores in the coating, followed by the formation of Cr2O3. As the exposure time increases, oxidation penetrates into the interior of the coating along phase boundaries to form island-shaped inner oxide layers with high concentrations of Cr, Ni, and Fe. Additionally, hardness increases with increasing oxide percentage.

In the current study, we sought to investigate whether T-type Ca(2+) channels (TCCs) in the brain are involved in generating post-anesthetic hyperexcitatory behaviors (PAHBs). We found that younger rat pups (postnatal days 9–11) had a higher incidence of PAHBs and higher PAHB scores than older pups (postnatal days 16–18) during emergence from sevoflurane anesthesia. The power spectrum of the theta oscillations (4 Hz–8 Hz) in the prefrontal cortex was significantly enhanced in younger pups when PAHBs occurred, while there were no significant changes in older pups. Both the power of theta oscillations and the level of PAHBs were significantly reduced by the administration of TCC inhibitors. Moreover, the sensitivity of TCCs in the medial dorsal thalamic nucleus to sevoflurane was found to increase with age by investigating the kinetic properties of TCCs in vitro. TCCs were activated by potentiated GABAergic depolarization with a sub-anesthetic dose of sevoflurane (1%). These data suggest that (1) TCCs in the brain contribute to the generation of PAHBs and the concomitant electroencephalographic changes; (2) the stronger inhibitory effect of sevoflurane contributes to the lack of PAHBs in older rats; and (3) the contribution of TCCs to PAHBs is not mediated by a direct effect of sevoflurane on TCCs.

Stroke-associated pneumonia (SAP) is a common cause of disability or death. Although the researches on SAP have been relatively mature, the method that can predict SAP with great accuracy has not yet been determined. It is necessary to discover new predictors to construct a more accurate predictive model for SAP. We continuously collected 2,366 patients with acute ischemic stroke, and then divided them into the SAP group and non-SAP group. Data were recorded at admission. Through univariate analyses and multivariate regression analyses of the data, the new predictive factors and the predictive model of SAP were determined. The receiver operating characteristic (ROC) curve and the corresponding area under the curve (AUC) were used to measure their predictive accuracy. Of the 2,366 patients, 459 were diagnosed with SAP. International normalized ratio (INR) (odds ratio = 37.981; 95% confidence interval, 7.487–192.665; P < 0.001), age and dysphagia were independent risk factors of SAP. However, walking ability within 48 h of admission (WA) (odds ratio = 0.395; 95% confidence interval, 0.287–0.543; P < 0.001) was a protective factor of SAP. Different predictors and the predictive model all could predict SAP (P < 0.001). The predictive power of the model (AUC: 0.851) which included age, homocysteine, INR, history of chronic obstructive pulmonary disease (COPD), dysphagia, and WA was greater than that of age (AUC: 0.738) and INR (AUC: 0.685). Finally, we found that a higher INR and no WA could predict SAP in patients with acute ischemic stroke. In addition, we designed a simple and practical predictive model for SAP, which showed relatively good accuracy. These findings might help identify high-risk patients with SAP and provide a reference for the timely use of preventive antibiotics.

This paper investigates the intensity noise and pulse oscillation characteristics of an InAs/GaAs quantum dot laser epitaxially grown on germanium. We show that the relative intensity noise of the free-running laser generally decreases with increasing pump current, and the minimum value reaches down to about $-$ 126 dB/Hz. The intensity noise is hardly affected by the optical feedback, unless there is a resonance or pulse oscillation in the noise spectrum. The laser pumped at a high current is more sensitive to the optical feedback. Interestingly, it is found that the free-running Ge-based quantum dot laser generates self-sustained pulse oscillations with one period or two periods upon the pump current, without incorporating saturable absorbers. This behavior is valuable for both self-generation of photonic microwaves and for understanding nonlinear dynamics of semiconductor lasers.

Chronic unpredicted mild stress(CUMS) combined with isolated feeding was used to induce depressed rat model. The anti-depressant effects of Zhizichi Decoction(ZZCD) and its solid fermented product(ZZC) were analyzed by behavioral test and comparison of pathological tissues of hippocampus and liver, metabolic characteristics of intestinal flora, and relative abundance of species. The results showed that ZZC could increase sucrose preference, shorten the immobility time in the forced swim test and tail suspension test(Plt;0.05), and repair damaged hippocampus and liver tissues, and the effect was superior to that of ZZCD. The results of Biolog ECO plates showed that the average well color development(AWCD) of intestinal flora in the model group significantly decreased and the metabolic levels of sugar and amino acids were reduced, while the AWCD of the treatment groups increased. The metabolic levels of the two carbon sources were improved in the ZZC group, while only sugar metabolic level was elevated in the ZZCD group. Metagenomic analysis of intestinal flora showed that the ratio of Firmicutes/Bacteroidetes was 3.87 in the control group, 21.77 in the model group, 5.91 in the ZZC group, and 18.48 in the ZZCD group. Lactobacillus increased by 3.28 times, and Prevotella and Bacteroidetes decreased by 75.59% and 76.39%, respectively in the model group as compared with that in the control group. Lactobacillus decreased by 31.13%, and Prevotella and Bacteroidetes increased by more than three times in the ZZC group as compared with that in the model group, while the corresponding changes in the ZZCD group were not significant. ZZC could improve depression-like beha-viors by regulating the structure of intestinal flora and metabolic functions and repairing damaged hippocampus and liver tissues in depressed rats, showing an anti-depressant effect superior to that of ZZCD. This study is expected to provide a basis for the development of new anti-depressant food products.

In this paper, it is found that the preferential growth of secondary {117} facets of Bi

Macroautophagy (referred to as autophagy hereafter) is a highly conserved catabolic process in eukaryotic cells. Autophagy is essential for cellular homeostasis through elimination and recycling of large cytoplasmic components, such as abnormal protein aggregates and damaged organelles, via lysosomal degradation. Since being originally identified by genetic screening in yeast, autophagy-related (ATG) genes have played a central role in autophagy research in different organisms, including plants, worms, flies, and mammals. Mouse models for monitoring autophagic activity or clarifying its biological functions have also been established. These mice are powerful tools to investigate roles of autophagy in vivo. Owing to the rapid technological advances in molecular biology, it is ever more efficient and simpler to manipulate autophagy-associated genes. Herein, we will introduce some commonly used approaches of gene silencing in mammalian cells, including CRIPSR/Cas9-mediated gene knockout and siRNA- and shRNA-mediated gene knockdown. We also summarized the common mouse models used for assessing autophagy. We hope to bring the researchers some useful information as they study autophagy.

OBJECTIVES The purpose of this study was to reveal the correlation between superior mesenteric artery (SMA) blood flow in the first 12 hours of life and the risk of necrotizing enterocolitis (NEC) in preterm neonates. METHODS We conducted a prospective study. There were 104 preterm neonates included in our study. The SMA blood flow of each neonate was measured during the first 12 hours of life if the hemodynamic situation was stable. The results of Doppler ultrasound were confidential to the neonatologists and nurses. All of the demographics, comorbidities, and outcomes were recorded and analyzed. RESULTS Among all of the demographics and comorbidities, the gestational age was related to the measurements of SMA blood flow. We conducted a single-factor analysis of the occurrence of NEC, including the peak systolic velocity (PSV), end-diastolic velocity, time-averaged mean velocity, differential velocity (DV), resistive index, and pulsatility index. A higher PSV (median [interquartile range], 54.165 [42.423-68.463] versus 42.195 [34.278-48.553] cm/s; P = .027) and DV (median [interquartile range], 47.445 [35.010-60.043] versus 32.565 [27.545-39.073] cm/s; P = .020) were significantly related to the risk of NEC. In the logistic analysis including gestational age, PSV, and DV, NEC was significantly associated with gestational age (odds ratio [95% confidence interval], 0.644 [0.456-0.908]; P = .012) and DV (odds ratio [95% confidence interval], 1.144 [1.058-1.237]; P

A palladium-catalyzed cross-coupling of unactivated alkylzinc reagents with 2-bromo-3,3,3-trifluoropropene (BTP) has been developed, which was used as a key step to prepare a series of trifluoromethylated and difluoromethylated amino acids that are of great interest in peptide/protein based chemical biology. The advantages of the synthesis of these fluorinated amino acids are synthetic simplicity and diversity from a simple and readily available key intermediate α-trifluoromethylalkene-containing amino acid, providing a facile route for applications in medicinal chemistry and life science.

Sonic-spray ionization (SSI) is a previously developed soft ionization technique which does not need auxiliary methods such as voltage, heating, laser, or corona discharge. Spray ionization can be achieved under normal temperature and atmospheric pressure by inputting high-speed gas coaxial within the capillary. As an atmospheric pressure ion source, this technique was widely used as the interface of liquid chromatography-mass spectrometry at the beginning of its development. Based on the principles of sonic-spray ionization, a variety of easy ambient sonic-spray ionization derived techniques have been developed, which can be used for the in-situ, rapid and real-time analysis of samples with little or without any sample pretreatment. In this paper, the principless and characteristics of sonic-spray ionization were elaborated, and the progress of its application in life sciences, food safety, forensic chemistry, reaction monitoring, and other related fields were summarized.

Macroautophagy (referred to as autophagy hereafter) is a highly conserved catabolic process in eukaryotic cells. Autophagy is essential for cellular homeostasis through elimination and recycling of large cytoplasmic components, such as abnormal protein aggregates and damaged organelles, via lysosomal degradation. Since being originally identified by genetic screening in yeast, autophagy-related (ATG) genes have played a central role in autophagy research in different organisms, including plants, worms, flies, and mammals. Mouse models for monitoring autophagic activity or clarifying its biological functions have also been established. These mice are powerful tools to investigate roles of autophagy in vivo. Owing to the rapid technological advances in molecular biology, it is ever more efficient and simpler to manipulate autophagy-associated genes. Herein, we will introduce some commonly used approaches of gene silencing in mammalian cells, including CRIPSR/Cas9-mediated gene knockout and siRNA- and shRNA-mediated gene knockdown. We also summarized the common mouse models used for assessing autophagy. We hope to bring the researchers some useful information as they study autophagy.

To compare the clinical effect on intestinal dysfunction of spinal cord injury (SCI) between the comprehensive therapy ofA total of 60 patients with intestinal dysfunction of SCI were randomized into a comprehensive therapy group and a rehabilitation group, 30 cases in each one (3 cases were dropped out in each group). On the base of the routine western medicine treatment and rehabilitation training, the bowel training and rectal function training were provided, once a day in the rehabilitation group. In the comprehensive therapy group, on the base of the treatment as the rehabilitation group, theAfter treatment, the total effective rate was 88.9% (24/27) in the comprehensive therapy group, which was higher than 74.1% (20/27) in the rehabilitation group (The comprehensive treatment of

This work demonstrates that a free-running Fabry-Perot quantum dot laser generates chaotic oscillations without any external perturbations, which is owing to the multimode Risken-Nummerdal-Graham-Haken instability.

OBJECTIVE The aim of the study was to investigate the biochemical and functional properties of a rat acellular pancreatic bioscaffolds (APBs). METHODS Fresh pancreata from 10 rats were soaked and perfused through portal veins using Easy-Load Digital Drive peristaltic pumps. The histological structure, extracellular matrix composition, and the DNA content of the APBs were evaluated. Biocompatibility studies had also been performed. The proliferation and differentiation of AR42J pancreatic acinar cells were assessed. RESULTS The pancreatic tissue became translucent after decellularization. There were no visible vascular endothelial cells, cellular components, or cracked cellular debris. The extracellular matrix components were not decreased after decellularization (P > 0.05); however, the DNA content was decreased significantly (P < 0.05). The subcutaneous implantation sites showed low immunological response and low cytotoxicity around the APB. The proliferation rate was higher and the apoptosis rate was lower when AR42J cells were cultured on APB (P < 0.05). The gene expression and the protein expression were higher for the APB group (P < 0.001). CONCLUSIONS Our findings support the biological utility of whole pancreas APBs as biomaterial scaffolds, which provides an improved approach for regenerative medicine.

In order to study the process and characteristic of the fragments in the warhead with one end cap under full constraint condition, we established a cylindrical casing with two end caps which one of them was fully constrained using the simulation analysis. The result showed that the fragmentation of cylindrical casing with one end full constrained has its own characteristic. The Mach stem was generated when the detonation wave propagated to the fully constrained end cap under the condition of one end detonation, working on unreactive explosives and causing the nearby fragment subjected to nearly 2.5 times the normal pressure to obtain a higher speed. The cylindrical casing first ruptured at the contact surface with the fully constrained end, and then at the end cover of the initiating end, and then the rupture extends to the whole cylindrical casing. The detonation products started to leak out from the rupture. driving fragments to fly, and forming two dense flying areas. The analysis of this paper can provide a reference for the optimal design of this kind of warhead.

Attribute-based access control is an effective cryptographic mechanism that allows a data owner to perform attribute-level access control over users’ access capabilities. In the application background of blockchain, it is urgent to use attribute-based access control to solve a series of security problems. Although there exist several similar schemes, they do not consider attribute revocation. By adopting the attribute revocation technique based on binary trees, we extended Waters’ ciphertext policy attribute-based encryption (CP-ABE) scheme into a revocable CP-ABE (RCP-ABE) scheme. By combining our RCP-ABE with blockchain, we constructed a revocable attribute-based access control system. The new system supports expressive access control policies and allows the attribute authority to revoke users’ attributes or part of their attributes. The security analysis shows that the new system satisfies several ideal properties, i.e., forward security, backward security, confidentiality, and integrity.

A convenient method for the preparation of 2-bromo-1, 1, 2, 2-tetrafluoroethyl arenes, using commercially available anilines and BrCF2CF2Br as starting materials is developed. The reaction processes in high efficiency under the irradiation of blue LED, enables installation of amino and fluoroalkyl moieties. Moreover, the product can easily transformed to many other 1, 1, 2, 2-tetrafluoroethylated reagents, thus demonstrates its high potential use for further modifications in the synthesis of functional molecules.

In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.

The impact of impurities on the microstructure and thermal shock resistance of YSZ TBCs was investigated. ZrO2-7.5wt%Y2O3 (7.5YSZ) coatings of 5 spices of compositions (4 of them were doped with one type of impurity, namely, Al2O3, Fe2O3, SiO2 and TiO2, and the other was not doped) were manufactured by APS. Thermal shock tests of these TBCs were carried out at 1100 °C, and the samples were quenched in cold water in the temperature range from 20 to 25°C. The microstructure evolution and phase analysis were performed before and after the thermal shock tests by scanning electron microscope (SEM) and X-ray diffractometer (XRD). The results showed that the thermal shock lifetime of YSZ TBCs doped with impurities was obviously reduced compared to that of no-impurity TBCs. Additionally, the differences in the microstructure and phases of YSZ TBCs were ascertained and the elements distribution was tested by Energy Dispersive Spectrometer (EDS) and Energy Dispersive X-Ray Spectroscopy (EDX).

A simple and efficient protocol for the direct N-difluoromethylation of imidazoles and pyrazoles has been developed. The reaction makes use of commercially available, non-ozone-depleting and easy handling BrCF2PO(OEt)2 as difluorocarbene precursor, and provides a cost-efficient and environmentally benign access to some difluoromethylated biologically relevant molecules.

InAs/GaAs quantum dot (QD) lasers monolithically grown on Ge or Si are a promising method to achieve low cost, large scale, and high yield optical sources for photonic integrated circuits [1]. This work shows that a free-running Ge-based QD laser can output periodic pulse oscillations with one, two and three periods, without incorporating saturable absorber or employing any external perturbations [2,3]. The QD laser under study was epitaxially grown on a 4-inch Ge-wafer by the gas-source molecular beam epitaxy, and the active region consists of five stacked dot-in-well layers [4]. The wafer was fabricated into a ridge-waveguide laser with a ridge width of 4.0 μm and a cavity length of 4.4 mm. The laser shows a lasing threshold of 60 mA at 20 °C, and the lasing peak is at 1213 nm. Figure 1(a) shows that the relative intensity noise (RIN) of the Ge-based laser pumped at 80 mA exhibits a common resonance with continuous-wave output. However, the resonance of the laser pumped at 160 mA does not become overdamped, but evolves into pulse oscillations with a high and sharp peak. Figure 1(b) shows the resonance frequency and the damping factor extracted from the RIN spectra. The resonance frequency increases with the pump current from 0.4 GHz at 80 mA up to 1.1 GHz at 170 mA, whereas the damping factor declines from 4.0 GHz down to 0.03 GHz. The damping reduction confirms the onset of peculiar pulsing dynamics for pump currents above 140 mA.

α-Trifluoromethyl alkenes can be used as peptide isosteres, moreover, the pre-installed vinyl group make it possible that transformation to diverse fluorine-containing unities. However, the cross-coupling of benzyl group with α-trifluoromethyl alkenes has yet to be developed. In this report, we describe a general method for the cross-coupling of benzylzinc reagents with 2-bromo-3,3,3-trifluoropropene (BTP) to afford diverse α-trifluoromethylalkene derivatives by using Pd(TFA)2 as catalyst. This method takes advantage of cheap industrial available fluorine building blocks and easily prepared benzylzinc reagents to generate α-trifluoromethylalkene derivatives, which features with mild reaction conditions, wide substrate scope and feasibility of product transformations.

To study the predictive value of procalcitonin as a serum biomarker in diagnosis of late periprosthetic joint infection(PJI) for providing theoretical reference basis for diagnosis of PJI.A total of 77 cases were retrospective included from January 2015 to December 2017 for revision of total hip arthroplasty and total knee arthroplasty, according to the diagnostic criteria of Musculoskeletal Infection Society(MISI). All cases were divided into infection group and non-infection group. Infection group included 21 cases, 7 cases for male and 14 cases for female, with an average age of (60.70±8.75) years old (ranged 43 to 75 years old). Non-infection group 56 included cases, 24 cases for male and 32 cases for female, with an average age (64.40±12.14) years old (ranged 43 to 85 years old). Concentration of preoperative serum procalcitonin was examined and the chi-square test was used to compare positive rate between the two groups.Two cases in the infection group had positive serum procalcitonin, 0.06 ng/L and 0.10 ng/L respectively, with the positive rate of 9.52%; 4 cases in non-infected group had positive serum procalcitonin, 0.05 ng/L, 0.06 ng/L, 0.06 ng/L, 0.16 ng/L respectively, with the positive rate of 7.14%. No statistically significant difference was observed between the two groups (Most of PJI were low toxicity infection with little systemic inflammatory response, so the concentration of serum procalcitonin was normal or slightly higher level, had little clinical significance for diagnosis of PJI. But the cases of this retrospective study are not enough, more cases are needed for further study.

This work experimentally investigates the optical feedback sensitivity of InAs/GaAs quantum dot (Qdot) lasers epitaxially grown on Ge substrate. In comparison with a Qdot laser on GaAs substrate with identical epilayer and cavity structures, the Ge-based laser is found to exhibit lower sensitivity to the optical feedback, although it has a higher epitaxial defect density. Theoretical analysis proves that the high defect density strongly increases the damping factor while slightly reduces the linewidth broadening factor, which lead to high tolerance to the optical feedback. This work suggests the high potential of Qdot lasers on Ge for isolator-free operation in photonic integrated circuits.

In order to solve the problems of low planning accuracy and high cost in traditional landscape plant landscape planning methods, a plant landscape planning method based on discrete particle swarm optimisation (DPSO) was proposed. The three-dimensional coordinate system of plant landscape planning path is transformed to determine the plant landscape planning path. The nonlinear programming mathematical model is used to constrain the plant landscape planning path, and the fitness objective function of plant landscape planning is obtained. The particle swarm optimisation algorithm is used to optimise the plant landscape planning path, and the particle swarm optimisation algorithm is used to improve the plant landscape planning path. The convergence was optimised to complete the plant landscape planning. The experimental results show that the accuracy of path planning is up to 98% and the aesthetic degree of plant landscape is more than 95%.

Silver nanowires–epoxy composites were prepared via cryomilling dispersion and hot-press forming process. The microstructure of the silver nanowires was studied by SEM. Dependence of dielectric properties of the composites on volume fraction of silver nanowires and frequency was investigated RF impedance material analyzer. The percolation threshold of the composites was 0.16, the value of the dielectric constant of the composite was as high as 100.

Barium ferrite micro/nanofibers were successfully prepared via the electrospinning by using dimethyl formamide (DMF) as the solvent, poly vinyl pyrrolidone (PVP) as the spinning auxiliaries and iron nitrate and barium nitrate as raw materials. The effect of poly vinyl pyrrolidone on the structure, morphology, magnetic and microwave absorbing properties were investigated by scanning electron microscope (SEM), X-ray diffraction analysis (XRD), vibration sample magnetometer (VSM) and vector network analyzer (VNA). XRD patterns of the samples confirmed that when the additive content of PVP was up to 10%, (wt%) pure barium ferrite fibers formed under the condition of the same heat treatment. Also, the FE-SEM images showed that the morphology of the fibers improved with the increase of PVP content. Moreover, the VSM results demonstrated that the saturation magnetization can reach 54.7 emu/g when the PVP dosage is 14% (wt%) in the precursor solution.

In practical applications of cylindrical explosive-filled casing, non-explosive materials or structures need to be filled at two ends, which make the ends of the casing have no corresponding explosive charge drive. If the non-explosive materials or structures are regarded as air, it is called cylindrical casing with air parts at two ends. The casing of air parts at two ends will be accelerated by the shock waves and detonation products generated from explosive charge, which cannot be predicted by Gurney formula because the mass ratio of explosive charge to metal casing is 0. In the present work, according to theoretical analysis and simulation, it was found that the existence of air parts at two ends would have no effect on the velocity distribution of fragments generated from the casing with explosive charge. In addition, the fragment velocities generated from air parts decreased exponentially with the increase of the distance from two ends, and the fragment velocities generated from air part at non-detonation end would also present an exponential decay with the increase of the length of air part at non-detonation end. A new formula was proposed to predict the axial distribution of fragment velocities of cylindrical casing with different length of air parts at two ends, which was detonated at one end. The proposed formula was further validated by experimentally verified numerical simulations, and the results showed that the average relative error was no more than 6.28%, RMSE was no more than 60.23 m/s, and R a d j 2 was more than 0.958, which indicated that the new formula could predict the axial distribution of fragment velocities very well. This work could provide reference for the theoretical analysis and the design of similar warhead.

In this paper, the microstructure of laser cladding layer was studied under two laser conditions. The microstructure of laser cladding layer was characterized as directional rapid solidification. On the premise of forming a good metallurgical bond between the coating and the matrix, higher laser energy density was harmful to refine the coating structure and reduce the microhardness of the coating.

This work theoretically investigates the four-level pulse-amplitude modulation characteristics of quantum dot lasers subject to optical injection. The rate equation model takes into account carrier dynamics in the carrier reservoir, in the excited state, and in the ground state, as well as photon dynamics and phase dynamics of the electric field. It is found that the optical injection significantly improves the eye diagram quality through suppressing the relaxation oscillation, while the extinction ratio is reduced as well. In addition, both the adiabatic chirp and the transient chirp of the signal are substantially suppressed.

This work demonstrates that the relative intensity noise of Ge-based epitaxial InAs quantum dot lasers are weakly sensitive to the temperature, while it is more sensitive to the optical feedback at higher bias currents.

To improve gas turbine performance, it is essential to decrease back flow gases in the high-temperature combustion region of turbo machine by reducing the shroud/rotor gap. An abradable seal coating will function effectively. Therefore, it is significant to identify and characterize the main wear mechanisms occurring on turbo machinery seals. A high temperature and speed test rig has been developed by BGRIMM for testing the AlSi–hBN abradable seal coating and Ti-6Al-4V dummy blade. Impact velocities between 150 and 300m·s-1 and incursion rates between 5.0 and 480 μm·s-1 have been applied. It was found that incursion rate has a greater impact on the wear mechanism of the AlSi–hBN coating, with tests at low incursion rate showing a obvious grooving and little micro-rupture, whereas tests at high incursion rate showing significant cutting and adhesion. The present work also shown that tests at low incursion rate related to a higher IDR, which means that blade suffered a serious wear. The investigation together with SEM and XRD analysis on the coating revealed both wear and adhesion occurred at the end of the test.

In this paper, discusses the school bus problem, given the mathematical model of route optimization, put forward an improved cuckoo search algorithm. Finally, take school bus routes running problem of Gansu Normal College for Nationalities as an example, the algorithm was experimented and the experimental results show that the algorithm to be successful.

A simple and efficient protocol for difluoromethylation of isoflavones, flavonoids, and coumarins has been developed. The protocol uses readily available, non-ozone-depleting and easy handling BrCF2PO(OEt)2 as difluorocarbene precursor. The reaction underwent the formation of difluorocarbene under mild reaction conditions with relatively weak base therefore demonstrates high selectivity. Application of the reaction led to difluoromethylated biologically relevant molecules.

In this paper, according to the characteristics of nonlinear equations. A Novel Firefly Algorithm was used to solve the nonlinear equations problem, the algorithm was experimented and the experimental results show that the new algorithm to be successful in locating multiple solutions and better accuracy. The experimental result demonstrates that the Improve firefly algorithm can get better solutions to nonlinear equations.