Search

Oxidative stress damage caused by free radicals around the moist microenvironment of wound has been a clinical challenge in skin tissue healing. Here, a novel chitosan-based bioinspired asymmetric wound repair composite (BAWRC) film was designed by facilitated endogenous tissue engineering strategy through layer-by-layer self-assembly technology for accelerated wound healing. The asymmetric characteristics were skillfully reflected by two different functional layers: hydrophilic chitosan (CS)/silk fibroin (SF) repair layer, and a hydrophobic bacteriostatic tea tree oil (TTO) layer with a rough surface. Simultaneously, sodium ascorbate (SA)-entrapped poly (lactic-co-glycolic acid) (PLGA) microspheres are distributed homogeneously in the hydrophilic layer to induce antioxidant response for skin repair. The distinctive asymmetric structure of BAWRC film endows it with synergistic effects, i.e., protects against the risk of infection from the external environment and facilitates deep skin wound healing. Results show that the minimum inhibition and bactericidal concentration of the BAWRC film were 1.25 and 6.25 mg/mL, respectively, demonstrating good antibacterial properties. The content of biofilm formation was significantly reduced when the concentration of TTO exceeds 5 mg/mL, indicating TTO shows a positive effect on bacteriostasis. In addition, the DPPH rates of BAWRC film were up to 64.7 % after incubation for 12 h, which was ascribed to that the release of SA and TTO as a natural product could accelerate free radical scavenging. The BAWRC film exhibited excellent biocompatibility, and good antibacterial capacity, enhancing adhesion and proliferation of the NIH3T3 cell in vitro, further facilitating the healing of a rat full-thickness skin wounds model. Herein, this versatile asymmetric film possesses great potential for clinical management of wound healing and related soft tissue regeneration.

At the moment, the SARS-CoV-19 pandemic is still attacking the health of humanity, and vaccines are the primary health strategy to eradicate this global challenge. So, with the exception of the SARS-CoV-2 vaccine, no vaccine for any disease has been brought to clinical use so quickly. Therefore, even with strict management, it can still bring some special adverse effects. One of the most notable is the adverse cardiovascular reactions to SARS-CoV-2 vaccines. No case reports of individuals with irreversible arrhythmia complications following the SARS-CoV-2 vaccine have been found in the available literature. We report the first case of a postoperative man with Marfan syndrome with atrial fibrillation after receiving the SARS-CoV-2 vaccine.

Lodging-tolerance is one of the most important goals in rice breeding. Due to its semi-dwarfism phenotype, dep1 can potentially improve lodging-tolerance. In this study, dep1 together with other three alleles, gs3, gn1a and ipa1, were integrated into high yield breeding strategy by conventional crossing and four combinations including dep1-gn1a, dep1-gs3, dep1-ipa1, and dep1-gs3-ipa1 were obtained. Though all the combinations showed plant phenotype similar to dep1, such as semi-dwarfism, short dense panicle, and short and erect flag leaf, their 1000-grain weight were observed to increase. Both dep1-ipa1 and dep1-gs3-ipa1 were characterized with improved lodging resistance and high yielding potential, while grain yield in both dep1-gn1a and dep1-gs3 dramatically decreased due to their low seed setting rate. Furthermore, specifically altered expression pattern of auxin and cytokinin related genes and abnormal stigma structure were found in two double mutant lines. Overall, current study demonstrated the potential of pyramiding dep1 conferring lodging-resistant trait with other high-yield related genes in cultivating elite rice varieties and additionally, providing a series of novel core germplasm for new insights into the interplay of dep1, gn1a, gs3, and ipa1 in regulating rice morphogenesis.

With its excellent electrical and mechanical properties and the rapid development of its device fabrication technologies, laser-induced graphene (LIG) has played an important role in the field of wearable technologies since its discovery in 2014. In recent years, with the relentless development of wearable devices, newly developed LIG-based wearable devices also possess multifunction and intelligence characteristics. This review is aimed toward two of the most important fields related to the development of LIG, namely, health care and human–computer interaction (HCI). We introduce multifunctional and intelligent LIG-based wearable systems for health care and HCI developed over the recent years, sorting out their design ideas, preparation process, performance, and application. Furthermore, we discuss the future development direction of LIG-based wearable systems for health care and HCI.

The rational synthesis of iron-sulfur clusters with excellent control of the core ligands has been a significant challenge in biomimetic chemistry. In this work, the rational construction of versatile Mo-Fe-S cubane clusters was realized using a LEGO strategy. (LEGO is a line of plastic construction toys consisting of various interlocking plastic bricks which can be assembled and connected in different ways to construct versatile objects. Herein we use "LEGO strategy" as an analogy for the stepwise synthetic methodology, and we use "brick" to represent a corner atom of the cubane structure.) Through careful synthetic control, the ⟨Fe⟩, ⟨S⟩, and ⟨Cl⟩ bricks were mounted piece-by-piece onto the basic ⟨MoS

Despite the prevalence of turning maneuvers in everyday life, relatively little research has been conducted on joint angle kinematic coordination during whole-body rotations around a vertical axis. Ballet pirouettes provide an opportunity to study dynamically balanced, whole-body rotations on a single support and the potential to scale results to smaller angular displacements executed by general populations. The purpose of this study was to determine the supporting limb’s ankle, knee, hip, and pelvis-trunk joint angle excursions and kinematic coordination strategies utilized during the pirouette’s turn phase. Advanced dancers (n = 6) performed pirouettes while whole-body 3-dimensional kinematics were recorded. Group mean ankle ab/adduction excursion was significantly greater than all other excursions (P

Photothermal therapy (PTT) has gained extensive interest in tumor treatments due to its non-invasive and low-toxic nature. However, the currently available photothermal agents (PTAs) mostly show unsatisfactory photothermal conversion efficiency (PCE). Besides, as a local cancer treatment modality, PTT fails to inhibit metastasis of tumors. To address these issues, in this study, two aza-boron-dipyrromethene (aza-BODIPY)-based organic photothermal agents (OPTAs), Fc-aza-BODIPY and TPA-aza-BODIPY, were rationally coined by introducing two strong electron-donating ferrocene (Fc) moieties and two triphenylamine (TPA) rotors, which could boost intramolecular photo-induced electron transfer (PET) and molecular rotation respectively, thereby improving the PCE of aza-BODIPY dyes. After encapsulation of hydrophobic Fc-aza-BODIPY (or TPA-aza-BODIPY) and quercetin with biodegradable PLGA and DSPE-mPEG2000, the resulting nanoparticles (FAQ NPs and TAQ NPs) showed excellent optical properties with PCE of ∼72.0% and ∼79.7% and specific tumor accumulations through enhanced permeability and retention (EPR) effects. Consequently, these two NPs possessed prominent antitumor effects under 880 nm laser irradiation. Moreover, both FAQ NPs and TAQ NPs loaded with quercetin could inhibit tumor metastasis efficiently. These two multifunctional nanomaterials integrating OPTAs and anti-metastasis agents constructed a cooperative treatment program, which may provide a potential opportunity for future clinical cancer treatment.

Wound dressing is a kind of significant artificial materials for protecting injured tissues and promoting wound healing. However, fabrication of antibacterial wound dressing usually involves tedious procedures and toxic components. Herein, we demonstrate a multifunctional chitosan/silver/tannic acid (CS/Ag/TA) cryogel based on an economic method to block acute hemorrhage and promote wound healing. The prepared CS/Ag/TA cryogel not only performs steady stability and compressibility, but also shows good antibacterial ability for both S. aureus and E. coli. Attributing to TA molecules, the CS/Ag/TA cryogel can effectively scavenge more than 95% of free radicals, showing effective oxidation resistance. Due to the porous structure and positive charge of CS, the prepared cryogel exhibits good hemostatic capability with a hemostasis time less than 20 s. Benefitting from the good biocompatibility and cell proliferation, the CS/Ag/TA cryogel can significantly promote wound repair in the skin incision model. All the results indicated that the greenly fabricated cryogel can be widely applied in clinic for hemostasis and wound healing.

Incorporation of monatomic 2p ligands into the core of iron-sulfur clusters has been researched since the discovery of interstitial carbide in the FeMo cofactor of Mo-dependent nitrogenase, but has proven to be a synthetic challenge. Herein, two distinct synthetic pathways are rationalized to install nitride ligands into targeted positions of W-Fe-S clusters, generating unprecedented nitride-ligated iron-sulfur clusters, namely [(Tp*)2 W2 Fe6 (μ4 -N)2 S6 L4 ]2- (Tp*=tris(3,5-dimethyl-1-pyrazolyl)hydroborate(1-), L=Cl- or Br- ). 57 Fe Mossbauer study discloses metal oxidation states of WIV 2 FeII 4 FeIII 2 with localized electron distribution, which is analogous to the mid-valent iron centres of FeMo cofactor at resting state. Good agreement of Mossbauer data with the empirical linear relationship for Fe-S clusters indicates similar ligand behaviour of nitride and sulfide in such clusters, providing useful reference for reduced nitrogen in a nitrogenase-like environment.

Flexible strain sensor devices were fabricated by depositing Pd nanoclusters on PET membranes patterned with interdigital electrodes. The sensors responded to the deformation of the PET membranes with the conductance changes of the nanocluster films and were characterized by both high gauge factor and wide detection range. The response characteristics of the strain sensors were found to depend strongly on the nanocluster coverage, which was attributed to the percolative nature of the electron transport in the closely spaced nanocluster arrays. By controlling the nanocluster deposition process, a strain sensor composed of nanocluster arrays with a coverage close to the effective percolation threshold was fabricated. The sensor device showed a linear response with a stable gauge factor of 55 for the applied strains from the lower detection limit up to 0.3%. At higher applied strains, a gauge factor as high as 200 was shown. The nanocluster films also demonstrated the ability to response to large deformations up to 8% applied strain, with an extremely high gauge factor of 3500.

In order to improve the capability of soft fault diagnosis in an analog circuit, an integrated diagnosis method based on KSLPP feature extraction and ELM is proposed. The KSLPP feature extraction ability is firstly used to construct the principal component feature set from the fault sample set. Then, the advantage of ELM on solving the complicated nonlinearity problem is applied to build the fault identification model from the principal component feature. Finally, the sample sets of soft fault diagnosis for the analog circuit are respectively established by waveform parameter and wavelet packet transform to conduct the diagnostic test for the built model. The simulation of Elliptic Filter shows that, based on the fault sample set gotten by waveform parameter, the total correct rate of the integrated method is 98.2%; on the basis of the fault sample set built by wavelet packet transform, the total correct rate is 100%. The feasibility and effectiveness of this method are also validated.

A highly efficient, green and sustainable protocol for rhodium(III)-catalyzed C-H alkylation of heterocycles with allylic alcohols has been achieved, which affords a series of β-aryl ketones in high yields. The reaction proceeds smoothly in water under air, and works well with heterocycles such as indoles, indolines, pyrroles and carbazoles. Notably, the expensive rhodium catalyst in water could be easily separated from the organic products, and reused for at least five times without loss of its catalytic activity and selectivity, which is a promising, green and sustainable pathway for the synthesis of β-aryl ketones. To the best of our knowledge, this is the first example for the reuse of expensive rhodium catalyst in water.

Structural mimicking of the nitrogenase FeMo cofactor has long been a challenge in synthetic inorganic chemistry and bioinorganic chemistry. This already very tough task had become even harder after the discovery of an interstitial light atom, which was later evidenced to be carbide. From a synthetic point of view, to introduce such a 2p atom into the core of a Fe–S cluster would have to overcome the coordination competition from overwhelming sulfide ligands. Recently, we have reported a controlled synthetic strategy named redox metathesis based on template-assisted structure design, and have successfully synthesized a couple of nitride-incorporated edge-bridged double cubane (N-EBDC) W–Fe–S clusters. In this work, we have systematically studied the terminal ligand substitutions of heteroleptic N-EBDC clusters, utilizing ethanethiolate, thiophenolate, p-thiocresolate, azide, and methoxide to replace the terminally bound chloride ligands. Structural analysis of this family of N-EBDC clusters reveals that different terminal ligands affect the fine structures of the cluster cores at different levels. Further studies by cyclic voltammetry indicate that these N-EBDC clusters with distinct terminal ligands exhibit different redox behaviors, furnishing in-depth information on the electronic structure of these clusters potentially related to their reactivity. This study provided useful information for the investigation of nitrogenase related Fe–S clusters toward structural and functional mimicking of the nitrogenase FeMo cofactor.

Additional file 1: Table S1. PERMANOVA results for the analysis of demographic characteristics associated with gut microbial community in 53 individuals based on BrayΓÇôCurtis distance.

Development of the drug with high therapeutic efficacy and low toxicity is crucial to cancer ablation. In this study, we have demonstrated a red light-responsive prodrug BDP-TK-CPT by connecting the chemotherapeutic agent camptothecin with a boron dipyrromethene (BDP)-based photosensitizer via a reactive oxygen species (ROS)-labile thioketal chain. Since camptothecin is modified by a BDP-based macrocycle at the active site, the formed prodrug displays an extremely low toxicity in dark. However, upon illumination by red light, it can efficiently generate ROS leading to cell death by photodynamic therapy. Meanwhile, the ROS generated can destroy thioketal group to release free camptothecin which further results in local cell death by chemotherapy. The combined antitumor effects of the prodrug have been verified in HepG2, EC109, and HeLa cancer cells and mice bearing H22 tumors. This study may provide an alternative strategy for stimuli-responsive combination treatment of tumors by conjugation of ROS-activatable prodrugs with photosensitizing agents.

Background: Paraquat is highly toxic pesticide, which usually led to acute lung injury and subsequently develop pulmonary fibrosis, the exact mechanisms of PQ-induced lung fibrosis remain largely unclear and no specific drugs for this disease have been approved. Methods: Our study aimed to identify its potential mechanism though modeling study in vitro and bioinformatics analysis. Gene expression datasets associated with PQ-induced lung fibrosis were obtained from the Gene Expression Omnibus and differentially expressed genes (DEGs) were identified using GEO2R. Functional enrichment analyses were performed using the Database for Annotation. Results: The DEGs in the two datasets, of which 92 overlapping genes were found in two microarray datasets. Functional analysis demonstrated that the 92 DEGs were enriched in the ‘TNF signaling pathway’, ‘CXCR chemokine receptor binding’, and ‘core promoter binding’. Moreover, nine hub genes were identified from a protein‑protein interaction network. Conclusions: This integrative analysis firstly identified candidate genes and pathways in PQ-induced lung fibrosis, as well as benefit to research novel approaches for treating for control of PQ-induced pulmonary fibrosis.

Jujube (Ziziphus jujuba Mill.) is an important perennial fruit tree with a range of interesting horticultural traits. It was domesticated from wild jujube (Ziziphus acidojujuba), but the genomic variation dynamics and genetic changes underlying its horticultural traits during domestication are poorly understood. Here, we report a comprehensive genome variation map based on the resequencing of 350 accessions, including wild, semi-wild and cultivated jujube plants, at a >15× depth. Using the combination of a genome-wide association study (GWAS) and selective sweep analysis, we identified several candidate genes potentially involved in regulating seven domestication traits in jujube. For fruit shape and kernel shape, we integrated the GWAS approach with transcriptome profiling data, expression analysis and the transgenic validation of a candidate gene to identify a causal gene, ZjFS3, which encodes an ethylene-responsive transcription factor. Similarly, we identified a candidate gene for bearing-shoot length and the number of leaves per bearing shoot and two candidate genes for the seed-setting rate using GWAS. In the selective sweep analysis, we also discovered several putative genes for the presence of prickles on bearing shoots and the postharvest shelf life of fleshy fruits. This study outlines the genetic basis of jujube domestication and evolution and provides a rich genomic resource for mining other horticulturally important genes in jujube.

Ultraviolet irradiation was used to tailor the surface plasmon band of the densely distributed aluminium nanoparticle arrays fabricated by gas-phase deposition. We showed that the broad surface plasmon resonance band of the as-prepared sample could be tuned to a sharp and strong resonance band in the deep ultraviolet optical range, with a large blue shift of the peak wavelength. The evolution of the surface plasmon resonance properties was attributed to the ultraviolet irradiation-improved surface oxidation of the nanoparticles, which eliminated the near-field couplings between the closely spaced nanoparticles by increasing their interspacing.

Highly reflective diffuse boards or integrating spheres illuminated with lamps are routine laboratory equipment for 2D radiometric calibration. The traceability chain to validate the measurement results is from absolute cryogenic radiometer (spectral power and then spectral power responsivity) through filter radiometer (spectral radiance at single wavelength), standard blackbody radiation sources (spectral radiance over a wavelength range), and calibrated spectroradiometers (spectral radiance responsivity over a wavelength range), to the large area spectral radiance sources for large area optical sensors and imaging spectroradiometers. However, due to (1) the fairly long traceability chain, (2) the non-uniformity of lamp illuminated diffuse boards and integrating spheres, (3) the relatively low spectral power from the broadband source for high spectral resolution, and so on, the calibration uncertainties for spectral radiance and irradiance responsivity are above the level of a few per cents. In order to improve the calibration performance, tunable lasers have been widely adopted to generate a large, uniform radiometric calibration source. For instance, an integrating sphere can be illuminated with a wavelength tunable laser to form a good spectral radiance field. Though very high laser power is necessary if the exit port of the integrating sphere is large. An alternative way is to directly unify and expand the laser beam for a good spectral irradiance field. In this work, we built a large, uniform, spectrally tunable irradiance field based on a Ti-Sapphire laser. First, two double-convex lenses were employed as a beam expander; second, a rotary diffuser was placed at the common focal point of the two lenses; thirdly, the expanded optical beam was then delivered onto and through a micro lens array to form a highly uniform spectral irradiance field with a size of 30 mm by 30 mm. The non-uniformity was measured to be 0.24% over a 20 mm by 20 mm area. The total optical losses through the beam expansion and unification system would be significantly reduced compared with integrating sphere method. The traceability chain is from the absolute cryogenic radiometer (spectral power and then spectral power responsivity) and the effective radiometric aperture area to the photodetector with a precision aperture (spectral irradiance responsivity), and then to the large, uniform, laser-based spectrally tunable irradiance field (spectral irradiance) for the calibration large size optical sensors and imaging spectroradiometers. The traceability chain is short, the non-uniformity is low, and the signal-to-noise ratio is high, compared to that based on the lamp illuminated boards and integrating spheres. Furthermore, the laser-based spectral irradiance field can be easily converted to a large, uniform spectrally tunable radiance field by simply placing a large-size, highly reflective diffuse board in the irradiance field. The laser-based irradiance and radiance field would play an important role for radiometric calibrations with low uncertainties.

Laser sources have been well adopted in spectrophotometry and optical materials measurements with excellent advantage of high spectral output power and hence large signal-to-noise ratio compared with traditional lamp sources. However, continuous wave lasers normally have very small tuning spectral range, due to either the limited bandwidth of the gain profile or low conversion efficiency due to the limited amount of pump power. Pulsed laser sources can be generated via nonlinear processes such as optical parametric oscillation or amplification and so on to cover a wide spectral range. For instance, supercontinuum laser sources have been developed with above 1 W/nm collimated spectral power over the visible to mid-infrared range. The output of the supercontinuum laser sources can be extended to cover UV range via second harmonic generation. Normally the spectral bandwidth of the output can be from tens to thousands nm and a monochromator or its equivalents can be used to select or tune the desired working wavelengths. The repetition rate of the laser sources can be from a few Hz to more than 1 GHz, with reduced pulse interval and efficiency due to more distributed pulse energy and hence peak power. A pulsed laser source with an original pulse width of ~ 130 fs, a repetition rate of ~ 80 MHz, and the spectral range from 280 to 2000 nm is applied for spectrophotometry calibration and research works have been devoted to converting the pulsed laser into continuous wave in order to improve the measurement linearity. Optical fiber bundles were used to divide each laser pulse into hundreds of small pulses via different optical path length and then recombine them for a temporally further distributed pattern. Two different types of optical fibers were adopted for the bundle, one for 280 nm ~ 700 nm wavelength range, and the other for 700 nm ~ 2000 nm. The numerical aperture of the optical fiber is 0.22 and the core diameter is ~ 200 μm. Each bundle has 100 pairs of optical fibers with different lengths. The refractive indices were extrapolated over the wide spectral range and used to calculate the optical fiber lengths for uniform time interval after recombination. The optical losses of the optical fibers over the wide spectral range were evaluated. After taking the spectral optical losses, fiber lengths, and input beam spatial power distribution into account, the arrangement of the optical fibers with different lengths at the input terminal was optimized for overall high performance over the two desired working spectral range. The time interval, relative power, spatial distribution of the distributed pulses throughout the designed optical fiber bundles were validated using a highspeed photodetector and oscilloscope. The optical fiber bundles can be useful for a variety of spectrophotometry calibration and optical materials measurement works using pulsed laser sources.

Here, we have synthesized and characterized a novel activatable photosensitizer (PS) 8a in which two well-designed boron dipyrromethene (BODIPY) derivatives are utilized as the photosensitizing fluorophore and quencher respectively, which are connected by a disulfide linker via two successive Cu (І) catalyzed click reactions. The fluorescence emission and singlet oxygen production of 8a are suppressed via intramolecular fluorescence resonance energy transfer (FRET) from the excited BODIPY-based PS part to quencher unit, but both of them can be simultaneously switched on by cancer-related biothiol glutathione (GSH) in phosphate buffered saline (PBS) solution with 0.05% Tween 80 as a result of cleavage of disulfide. Also, 8a exhibits a bright fluorescence image and a substantial ROS production in A549 human lung adenocarcinoma, HeLa human cervical carcinoma and H22 mouse hepatoma cells having a relatively high concentration of GSH, thereby leading to a significant photocytotoxicity, with IC50 values as low as 0.44 μM, 0.67 μM and 0.48 μM, respectively. In addition, the photosensitizer can be effectively activated and imaged in H22 transplanted hepatoma tumors of mice and shows a strong inhibition on tumor growth. All these results suggest that such a GSH-responsive photosensitizer based on FRET mechanism may provide a new strategy for tumor-targeted and fluorescence imaging-guided cancer therapy.

Molybdenum-dependent nitrogenases catalyze the transformation of dinitrogen into ammonia under ambient conditions. The active site (FeMo cofactor) is the structurally and electronically complex weak-field metal cluster [MoFe 7 S 9 C] built of Fe 4 S 3 and MoFe 3 S 3 C portions connected by three sulfur bridges and containing an interstitial carbon atom centered in an Fe 6 trigonal prism. Chemical synthesis of this cluster is a major challenge in biomimetic inorganic chemistry. One synthetic approach of core ligand metathesis has been developed based on the design and synthesis of unprecedented incomplete ([(Tp*)WFe 2 S 3 Q 3 ] − ) and complete ([(Tp*)WFe 3 S 3 Q 4 ] 2− ) cubane-type clusters containing bridging halide (Q = halide). These clusters are achieved by template-assisted assembly in the presence of sodium benzophenone ketyl reductant; products are controlled by reaction stoichiometry. Incomplete cubane clusters are subject to a variety of metathesis reactions resulting in substitution of a μ 2 -bridging ligand with other bridges such as N 3 − , MeO − , and EtS − . Reactions of complete cubanes with Me 3 SiN 3 and S 8 undergo a redox metathesis process and lead to core ligand displacement and formation of [(Tp*)WFe 3 S 3 ( μ 3 -Q)Cl 3 ] − (Q = Me 3 SiN 2− , S 2− ). This work affords entry to a wide variety of heteroleptic clusters derivable from incomplete and complete cubanes; examples are provided. Among these is the cluster [(Tp*)WFe 3 S 3 ( μ 3 -NSiMe 3 )Cl 3 ] − , one of the very few instances of a synthetic Fe–S cluster containing a light atom (C, N, O) in the core, which constitutes a close mimic of the [MoFe 3 S 3 C] fragment in FeMo cofactor. Superposition of them and comparison of metric information disclose a clear structural relationship [Tp* = tris(3,5-dimethyl-1-pyrazolyl)hydroborate(1−)].

The functionalized ligand 9,10-anthraquinone-1,4-dicarboxylate acid (H2AQDC) was designed and synthesized in order to develop metal-organic coordination polymers as heterogeneous catalysts with a photosensitizing feature. Two major considerations of the ligand design are anthraquinone moieties for photosensitizing to harvest light and carboxylate groups for polymeric coordination toward less solubility. A series of transition metal complexes based on this ligand were synthesized subsequently, namely {Co(AQDC)(H2O)3·2H2O}n (Co-AQDC), {Ni(AQDC)(H2O)3·2H2O}n (Ni-AQDC), {[Cu(AQDC)(H2O)3][Cu(AQDC)(H2O)2(DMF)]·(H2O)4}n (Cu-AQDC), {Zn1.5(AQDC)(OH)(H2O)2·H2O}n (Zn-AQDC), {Ag2(AQDC)(CH3OH)}n (Ag-AQDC). Both the ligand and its transition metal complexes are able to catalyze the visible-light driven oxidation reactions of alkynes into 1,2-diketones in air under mild conditions, in which compound Ni-AQDC demonstrates the best activity. This catalyst can be easily isolated from the reaction mixture by filtration with a trace amount of loss in solution and is ready for recycled use after simple washing and drying without any need for regeneration. Remarkably, the catalyst shows no loss of activity after five catalytic cycles and X-ray powder diffraction proves no change in the structure after five runs. This designed metal-organic coordination polymer represents an environmentally friendly, economical and recyclable photocatalyst, constituting a good candidate for photocatalytic organic syntheses in terms of green chemistry.

Osteoarthritis disease can easily lead to articular cartilage degeneration and subchondral bone damage, so the demand for suitable articular substitutes is gradually increasing. In order to simulate the complex environment of different layers in natural joint, we fabricate the continuous one-phase gradient scaffold. In the study, CS (chitosan) was modified with SH (sodium hyaluronate) and GO (graphene oxide) to form the whole scaffold. nHAP (Nano-hydroxyapatite) was in situ generated with gradient distribution in the scaffold. Continuous interface can better imitate the combination style of cartilage and subchondral bone at joint. The diverseness of scaffold’s different layer in water absorption/retention rate and mechanical property is similar to the difference of articular cartilage and subchondral bone. Meanwhile, the cell experiments demonstrated that the bionic scaffold can well promote the proliferation of bone marrow mesenchymal stem cell. Articular defect model further confirmed that the scaffold can better induce articular regeneration. Herein, the prepared scaffold might be an excellent candidate for endogenous articular repair.

The objective of this paper is to analyze the relationship between the carbon emission, GDP and its growth rate, energy consumption, and unemployment rate in case of the United States and moreover, we also aim to explore where US and the fifty states now lie on the Kuznets curve. By using the panel data to investigate five different districts from 2000 to 2015 and the US as a whole, the empirical results indicate a long-run equilibrium relationship between variables and the positions the United States and its different states now lie on the curve. These findings suggest that the United States should adopt other low-carbon supporting policies and technologies to real-ize the movement from the left side of the curve to the right side of it, with the major goal to abstain from negatively affecting economic development by decreasing vitality utilization.

With the development of electric power system, Power-frequency Magnetic Field (MF) has become a matter of concern recently. In order to speed up the computation and modeling process, the small-scale experimental technique and simplified model for air-core reactors are introduced as a novel way to assess the MF of air-core reactors in this paper. Firstly, the scaling rules of the parameters for air-core reactors are summarized. Then, the scaling rules modification is put forward to reduce the error. Thirdly, three simplified models were established for air-core reactors, including one loop model, two loops model and three loops model. It is concluded after that the two loops model in configuration 2 can be considered as the optimal simplified model.

Air-core reactors have become the main source of electromagnetic contamination in substations. In this project, the scaling methods for small-scale experimental technique will be studied, in order to provide validation of the analytical and numerical calculation, and to help to predict the MF around air-core reactors. Firstly, the scaling rules of the parameters for air-core reactors are summarized firstly. Then a full size, 1/2 size 1/6 size of air-core reactors are put forward in order to study the MF of the origin size by analytical calculation, numerical simulation and small-scale experiment. All the results verify the effectiveness of the scaling rules and the equivalency of small-scale experiments.

the reliability and vibration performance test of vibratory rollers have been done in the test field to ensure that the vibratory roller meet the quality requirement. At present, the indoor test stand for vibratory roller has not yet been studied at home and abroad. This paper designs the indoor test stand for vibratory roller and makes simulation analysis by the numerical model of vibration-drum and test stand. The vibration isolation system of test stand is determined as a function of the test stand mass (m2), the stiffness of rubber tire (k1) and the stiffness of the vibration isolation block (k2). The test results showed that the vibration drum-test stand model can account for the vibration isolation system.

In this work, the degradation of GaN-based packaged white light-emitting diodes (LEDs) caused by accelerated humidity testing will be investigated using non-destructive failure analysis tools, namely the mixed statistical distribution, spectrum analysis and parameters extraction. Physical failure analysis techniques are then used to verify and conclude the deduced failure mechanisms obtained by the non-destructive failure analysis tools.

An automatic multi-wavelength filter radiometer (MWFR) was developed at the National Metrology Centre (NMC) of Singapore to realize the spectral irradiance scale in the wavelength range from 250 nm to 1600 nm. The UV–VIS range (250 nm to 900 nm) is covered by a silicon trap detector with 17 filters, while the near IR range (900 nm to 1600 nm) is covered by an InGaAs photodiode with 7 filters. A complete run of measurements at all 24 wavelength points takes only 12 min. The spectral irradiance scales of NMC and MIKES/TKK (Finland) in the spectral range from 280 nm to 900 nm were compared successfully using this instrument. Measurement results of three standard lamps calculated using MIKES/TKK's algorithm showed excellent repeatability and very good agreement with their assigned values. It is concluded that, compared with the conventional monochromator based spectroradiometers, a properly designed MWFR with sufficient spectral coverage is a good alternative instrument for spectral irradiance comparison owing to its faster speed and better short-term reproducibility.

The cascading (step-down) technique is often employed in spectral regular transmittance measurement of high optical density samples using a spectrometer in order to improve its measurement accuracy and to extend its measuring range. The uncertainty evaluation for such a measuring process is more complicated than that for a single-step measurement. In this paper, we focus on the evaluation of the uncertainty induced by wavelength-setting in the spectrometer, which is of particular importance when the transmittance of the sample at the wavelength of measurement is not spectrally flat, making its contribution to the total uncertainty dominant. It is shown that for glass filters commonly used for calibration of spectrometers the evaluation can be greatly simplified after taking into account the correlation effect arising from the cascading process. The proposed methods were validated by direct experimental verification.

To observe the chronic combined effects of sodium fluoride and sodium arsenite on the Runx2 and downstream related factors of bone metabolism in SD rats.SD rats were divided randomly into nine groups of 6 each by factorial experimental design (half female and half male) , and supplied with the different doses of fluoride, arsenite and fluoride plus arsenite containing in deionized water (untreated control containing 0 mg/kg fluoride and 0 mg/kg arsenite, and low-fluoride and high supplemented with 5 and 20 mg/kg fluoride, and low-arsenite and high supplemented with 2.5 and 10 mg/kg arsenite, and low-fluoride plus low-arsenite, and low-fluoride plus high-arsenite, and high-fluoride plus low-arsenite, and high-fluoride plus high-arsenite, respectively) . After 6 months exposure, the concentration of Runx2, matrix metallopeptidase 9 (MMP-9) ,Osterix, Receptor activator for nuclear factor-κ β ligand (RANKL) were detected by enzyme-linked immunosorbent assay method, respectively.There were no dental fluorosis found in the control group, low-arsenic group and high-arsenic group. There were significant differences in the constituent ratio of dental fluorosis among the rats from low-fluoride and high-fluoride (that is 5 rats out of 6 and 6 rats out of 6) compared with the control group (0 rat out of 6) (χ(2) = 8.57, 12.00, P0.05). The bone fluorine level increased with the increase of fluoride dose, the groups without fluoride supply (control group, low-arsenite and high-arsenite group's geometric mean (minimum-maximum) were 0.005 (0.003-0.009), 0.006 (0.003-0.021), 0.003 (0.002-0.100) mg/g, respectively), low-fluorine groups (low-fluoride group, low-fluoride plus low-arsenite, and low-fluoride plus high-arsenite group were 3.395 (2.416-5.871), 3.809 (1.471-7.799), 1.471 (1.473-6.732)mg/g, respectively) , the high-fluorine groups (high-fluoride, high-fluoride plus low-arsenite, and high-fluoride plus high-arsenite group were 70.086 (46.183-131.927), 69.925 (40.503-96.183), 40.503 (52.622-89.487) mg/g, respectively) and the differences between groups was significant (P0.05). The bone arsenic level increased with the increase of arsenite dose. The low-arsenic groups (low-arsenite group, low-arsenite plus low-fluoride, and low-arsenite plus high-fluoride group were 7.195 (5.060-9.860), 6.518 (2.960-12.130), 6.970 (3.400-9.730) µg/g, respectively), the high-arsenic groups (high-arsenite, high-arsenite plus low-fluoride, and high-fluoride plus high-arsenite group's geometric mean(minimum-maximum) were 8.823 (5.760-10.840), 9.470 (7.230-12.860), 8.321 (2.420-17.540) µg/g, respectively) were significantly higher than that in the groups without arsenic supply (control group, low-fluoride and high-fluoride group were 1.785 (0.300-3.750), 2.226 (1.410-3.980), 2.030 (1.040-3.850)µg/g, respectively) (P0.05). There was no significant difference of the bone arsenic concentration between low-arsenic and high arsenic group. There was significant positive correlation between fluoride concentration and Runx2, MMP-9, Osterix, RANKL level (the correlation coefficient was 0.647, 0.354, 0.582, 0.613 between fluorine gavage concentration and protein level, the correlation coefficient was 0.559,0.387, 0.487, 0.525 between bone fluorine concentration and protein level, respectively, P0.01). There was negative correlation between arsenite gavage concentration with Runx2 level (r = -0.527, P0.05) and was no correlation between arsenite gavage concentration with MMP-9, RANKL,Osterix level (P0.05). There was interaction between fluoride and arsenite to Runx2, MMP-9, RANKL,Osterix (F = 3.88, 15.66, 2.92, 6.42, respectively, P = 0.01,0.01, 0.031,0.01, respectively).The combined effects of fluoride and arsenic on the Runx2, MMP-9, RANKL, Osterix of bone metabolism showed antagonistic effects.

The effects on the calibration uncertainties of industrial ultraviolet radiometers of spatial non-uniformity in the irradiance beam and detector response are studied both theoretically and experimentally. The results show that an error of a few parts in 102 or more could easily arise from the non-uniformity of the beam used in calibration if the effective receiving area of the test meter head differs significantly from that of a standard meter head. This error can be removed effectively by an area-correction technique based on a charge-coupled-device (CCD) camera.

Human ALR gene sequence was amplified by PCR from human total DNA and inserted into pIRES(2)-EGFP vector. The bicistronic eukaryotic expression vector, pIRES-EGFP/ALR, expressing EGFP, Neo(r) and ALR genes was constructed. Sheep fetal fibroblast cells (sEFCs) were transfected with pIRES-EGFP/ALR by the induction of lipofectAMINE(TM). The positive cell clones were selected with medium containing G418 (800 μg/mL). The fluorescence of transgenic cells was examined with a confocal laser scanning microscope. The expression of ALR gene was tested by PCR, RT-PCR and immuno-histochemical staining. The transgenic cells were used as donors for nuclear transfer to enucleated ovine oocytes. Transgenic embryos were tested by confocal laser scanning microscope and immuno-histochemical staining. Results showed that the EGFP and ALR genes linked with IRES were coexpressed simultaneously in sFFCs; the blastocysts formed by nuclear transfer using tranfected donor cells are all transgenic blastocysts. EGFP, ALR and Neo(r) gene were all expressed in the transgenic embryos. In conclusion that a method to construct the positive embryos before pre-implantation which stably express ALR gene by the indication of EGFP expression has been successfully established. The application of this method can simplify the procedure of testing the targets and contribute to the efficiency increasing of transgenic domestic animal production.

The time-of-flight method was used to calibrate an optical fiber length standard and its uncertainty of measurement was evaluated theoretically and experimentally according to the Evaluation of measurement data - Guide to the expression of uncertainty in measurement (GUM), JCGM 100:2008. The major uncertainty components in the measurement of transit time difference were identified and analyzed. The uncertainty due to temperature instability was investigated experimentally in the temperature range from 20 °C to 25 °C using a temperature chamber with precise temperature control. The temperature coefficient of the fiber length standard was derived by linear regression of the measurement data. The experimental results showed that the temperature control is critical for the calibration of optical fiber length standard. When the temperature instability was improved from ± 2 °C to ± 0.1 °C, the expanded measurement uncertainties for the optical fiber length standard (optical length : ~11780 m) were significantly reduced from 0.16 m to 0.014 m at wavelength of 1310 nm and from 0.19 m to 0.015 m at wavelength of 1550 nm.

In China, it is more and more difficult and expensive to see a doctor. One of the deep reasons goes to the situation that the hospitals and medicine are bound together and that medicine is supplemental to support the hospitals. This article sets forth a brief and direct balance model on supply and demand in pharmaceutical market and analyses the policy of separation of pharmacies from hospitals on Micro-Economics. The construction of the models and analysis has provided a new solution to solve the problem of fostering hospitals with medicine and to implement the separation of hospitals and medicine.

Phase conjugation reflectivity greater than unity has been obtained in BSO in the wavelength range 570–590 nm via degenerate four-wave mixing in the usual retroreflection geometry by applying an audio-frequency ac-sinusoidal electric field. An intensity modulation at twice the field frequency in the generated signals was observed for the first time.

This study was purposed to investigate the angiogenin (ANG) expression in COS-7 cells and its biological activity. The gene of angiogenin was obtained from mononuclear cells of peripheral blood by using RT-PCR and inserted into eukaryotic expression vector of pcDNA3.1. After being transfected into COS-7 cells, the recombinant ANG was identified by Western blot assay. The function of promoting proliferation of ANG to ECV304 cells was detected by MTT method, and its activity of vascularization was analyzed by chick embryo chorioallantois treated by the culture supernatant after transfection with pcDNA3.1-ang. The result showed that recombinant ANG was expressed in COS-7 cells after transfection for 24 to 36 hours. It could specifically react with monoclonal antibody against ANG. The recombinant ANG could obviously promote the proliferation of ECV304 cells. In contrast with the control group, the culture supernatant of pcDNA3.1-ang transfected group could stimulate the angiogenesis in embryo chorioallantois. It is concluded that the ang transiently expresses in COS-7 cells, and its expression product obviously stimulates the cell proliferation and angiogenesis.

Fertilin beta may play an important role in sperm-egg plasma membrane adhesion and fusion. To explore the effects of fertilin beta, the sperm membrane protein subunit, in the sheep fertilization process, we used RACE technique for cloning the full length cDNA of the coding region (CDS) of fertilin beta. The coding region was 2, 217 bp, which consists of 738 amino acids. The fertilin beta in the sperm membrane of sheep shares 79.4%, 66.7%, and 58.1% sequence identity with that in bovine, pig and human, respectively. The phylogenetic analysis of the fertilin beta gene family indicated the fertilin beta was clustered with bovine, and is closest to the one of bovine. This result is consistent with the result of the traditional classification. The protein structure analysis showed the disintegrin domain of sheep fertilin beta contains a TDE. Besides the above tripeptide sequence, the family member of ADAM (A Disintegrin and A Metalloprotease) follow the conserved sequence of ECD of X-D/E-E, and formed the conserved sequence of X-D/E-ECD. The pentapeptide sequence of the sheep fertilin beta is TDECE.

User adaptation is critical in the future design of human-computer interaction systems. Many pattern recognition problems, such as handwriting/sketching recognition and speech recognition, are user dependent since different users' handwritings, drawing styles, and accents are different. Hence, the classifiers for solving these problems should provide the functionality of user adaptation so as to let all users experience better recognition results. However, the user adaptation functionality requires the classifiers have the incremental learning ability in order to learn fast. In this paper, an SVM-based incremental active learning algorithm is presented to solve this problem. By utilizing the support vectors and only a small portion of the nonsupport vectors as well, in addition to the new interrogative samples, in the iterative training and reclassification cycle, both the training time and the storage space are saved with only very little classification precision being lost. Theoretical analysis, experimentation, evaluation, and real application samples in our online graphics recognition system are presented to show the effectiveness of this algorithm.

A special calibration tool has been developed for a CCD camera based vision system in an automatic assembly machine. The machine is used to attach orifice plates onto a silicon wafer in a production process. The center locations of the positioning circular holes on the plate must be controlled accurately to coincide with those on the wafer die before they are attached together by UV curing. Although CCD camera based vision systems are widely used for accurate positioning and dimensional measurements in precision engineering, electronics and semiconductor industry, their calibrations are normally done by artefacts with plane patterns. These artefacts are therefore restricted to only two dimensional measurements. The calibration tool we developed was to check the positioning accuracy of circular objects in a two-layered structure. It can also be used to determine parallax errors, non-linearity and spatial non- uniformity errors as well as repeatability of the vision system with an uncertainty at sub-micrometer level. The design, calibration and performance of the tool are described in detail in this paper.

We have constructed a laser measurement system for automatic calibration of height setting micrometer. This automation is accomplished by an interactive software tool which performs essential calibration functions. The instrument incorporates a double frequency stabilized laser based on the heterodyne measurement technique. Positioning of height setting micrometer is undertaken by a X-Y stage driven by the servo motors and calibration is performed by combining laser and electronic probe readings. Abbe offset tilting error is eliminated by using the double-path interferometer scheme. The instrument has a capability of measurement range 0 - 350 mm, resolution 40 nm, expanded uncertainty of height measurement better than 0.5 micrometer at the 95% confidence level over the full range. The whole calibration procedure can be completed in two hours making it much more efficient than the conventional method of gauge block comparison. The instrument can also be applied to various linear measurements with high accuracy to reduce the measuring time and to simplify the measurement setup.