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The differences in the cross-sectional positions of cells in the detection area have a severe negative impact on achieving accurate characterization of the impedance spectra of cells. Herein, we proposed a threedimensional (3D) inertial focusing based impedance cytometer integrating sheath fluid compression and inertial focusing for the high-accuracy electrical characterization and identification of tumor cells. First, we studied the effects of the particle initial position and the sheath fluid compression on particle focusing. Then, the relationship of the particle height and the signal-to-noise ratio (SNR) of the impedance signal was explored. The results showed that efficient single-line focusing of 7–20 μm particles close to the electrodes was achieved and impedance signals with a high SNR and a low coefficient of variation (CV) were obtained. Finally, the electrical properties of three types of tumor cells (A549, MDA-MB-231, and UMUC-3 cells) were accurately characterized. Machine learning algorithms were implemented to accurately identify tumor cells based on the amplitude and phase opacities at multiple frequencies. Compared with traditional two-dimensional (2D) inertial focusing, the identification accuracy of A549, MDA-MB-231, and UM-UC-3 cells using our 3D inertial focusing increased by 57.5%, 36.4% and 36.6%, respectively. The impedance cytometer enables the detection of cells with a wide size range without causing clogging and obtains high SNR signals, improving applicability to different complex biological samples and cell identification accuracy. [ABSTRACT FROM AUTHOR]

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique, integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase (ALP), was developed. Initially, a pre-cured hydrogel of regenerated silk fibroin (RSF) with a small quantity of hydroxypropyl cellulose (HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate (Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization process. Moreover, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures. [ABSTRACT FROM AUTHOR]

As a new generation of chip-packaging materials, CaSiO 3 LTCC substrates have the characteristics of high frequency, low thermal expansion coefficient, and low dielectric loss. These materials are widely used in radar communication and other industries. However, in the condition of high heat density, it is difficult to adapt calcium silicate with a low thermal conductivity to the heat dissipation requirements. To improve the heat dissipation performance, high-aspect-ratio heat-dissipation microchannels must be prepared on the surface of the CaSiO 3 LTCC substrate. In this study, a new nanosecond laser and chemical milling-assisted micro-milling (NLCAM) method is proposed. The processing mechanism of the nanosecond laser ablation of CaSiO 3 is explored and the influence of the laser parameters on the depth of the etching groove, top width, and hardness of the residual modified layer are studied by establishing a laser energy superposition model and test method. The improvement of milling force and milling surface quality by laser is studied. The results demonstrate that the laser power has the most significant effect on the ablation depth and width of the top of the CaSiO 3 ; the excess heat diffuses outside the laser irradiation area, increasing the width of the top of the CaSiO 3 beyond the designed width. With an increase in the scanning speed and scanning distance, the ablation depth exhibited a decreasing trend, corresponding to the laser energy model. Nanosecond laser chemical milling (NLCM) can reduce the hardness of the material by 72.0–77.2%. The maximum reduction in the average axial milling force was 56.8%, and the fluctuation of milling force is reduced. Compared to pure micro milling, the tool wear area of NLCAM was reduced by 89.3% and the average roughness Sa of the bottom surface of the microgroove was reduced to 0.392 μm, which confirms the high-quality and efficient machining of the CaSiO 3 LTCC substrate. [ABSTRACT FROM AUTHOR]

Over the past decade, the field of holography has gained significant ground due to advances in computational imaging. However, the utilization of computational tools is hampered by the mismatch between experimental setups and the conceptual model. Differentiable holography (∂H$\bm{\partial }\mathbf {H}$), a novel framework for automatically self‐calibrating experimental imperfections in inverse holographic imaging, is presented here. The technique is demonstrated on auto‐focused complex field imaging from a single intensity‐only inline hologram. [ABSTRACT FROM AUTHOR]

To explore the predictive value of quantitative features extracted from conventional magnetic resonance imaging (MRI) in distinguishing Zinc Finger Translocation Associated (ZFTA)-RELA fusion-positive and wild-type ependymomas. Twenty-seven patients with pathologically confirmed ependymomas (17 patients with ZFTA-RELA fusions and 10 ZFTA-RELA fusion-negative patients) who underwent conventional MRI were enrolled in this retrospective study. Two experienced neuroradiologists who were blinded to the histopathological subtypes independently extracted imaging features using Visually Accessible Rembrandt Images annotations. The consistency between the readers was evaluated with the Kappa test. The imaging features with significant differences between the 2 groups were obtained using the least absolute shrinkage and selection operator regression model. Logistic regression analysis and receiver operating characteristic analysis were performed to analyze the diagnostic performance of the imaging features in predicting the ZFTA-RELA fusion status in ependymoma. There was a good interevaluator agreement on the imaging features (kappa value range 0.601–1.000). Enhancement quality, thickness of the enhancing margin, and edema crossing the midline have high predictive performance in identifying ZFTA-RELA fusion-positive and ZFTA-RELA fusion-negative ependymomas (C-index = 0.862 and area under the curve= 0.8618). Quantitative features extracted from preoperative conventional MRI by Visually Accessible Rembrandt Images provide high discriminatory accuracy in predicting the ZFTA-RELA fusion status of ependymoma. [ABSTRACT FROM AUTHOR]

Objective: To explore the value of magnetic resonance imaging (MRI) in fetuses with periventricular pseudocysts (PVPC) and the neurodevelopmental outcomes of these fetuses via meta-analysis. Methods: MEDLINE and EMBASE database were searched for studies reporting on the MRI assessment of fetuses diagnosed with PVPC on neurosonography. The neurosonography was conducted according to the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG) guidelines or standard axial, coronal and sagittal planes for advanced central nervous system (CNS) assessment. Single-shot fast spin-echo T2-weighted sequences of MRI technique in three orthogonal planes were necessarily performed. The pooled proportion of CNS anomalies missed on neurosonography and detected only at prenatal MRI was calculated. Subanalysis was performed according to the types of intracranial anomalies. The pregnancy outcomes (including normal, abnormal, termination of pregnancy, and perinatal death) of PVPC fetuses were also analyzed. Results: Five studies comprising 136 fetuses were included in this meta-analysis. Mean gestational age was 29.8 weeks (16–38 weeks) at ultrasonography and 31.5 weeks (25–37 weeks) at MRI. Overall, MRI detected exclusively CNS anomalies in 25.2% (95% CI 15.9–35.8%) of cases. Among them, the highest incidence was white matter abnormalities with the pooled proportion of 16.3% (95% CI 9.7–24.2%). When getting rid of white matter abnormalities, the risk of associated CNS anomalies only detected on MRI was reduced to 9.1% (95% CI 1.8–21.4%). Meanwhile, 130 cases were studied to assess the pregnancy outcomes with the scope of 1 month to 10 years. The pooled proportion of normal outcomes in isolated PVPC fetuses was as high as 95.0% (95% CI 83.9–99.8%). When analyzing the neurodevelopmental outcomes in non-isolated PVPC fetuses, the incidence of normal neurodevelopmental outcomes was about 22.1% (95% CI 5.6–45.5%) with mild and single additional abnormalities, the rate of abnormal neurodevelopmental outcomes was 19.5% (95% CI 11.0–29.7%) with apparent and/or multiple abnormalities. Besides, 53.6% (95% CI 35.4–71.3%) of non-isolated PVPC cases were terminated mainly due to infections, genetic anomalies, metabolic disorders and hemorrhage. Conclusions: MRI assessment of PVPC fetuses is recommended to detect associated intracranial anomalies that may be missed on dedicated neurosonography. White matter abnormalities on MRI account for the majority of additional anomalies, which might to be the clue of CMV infection, aminoacidopathy or white matter disease. Moreover, the neurodevelopmental outcome of isolated PVPC fetuses remains favorable, while the neurodevelopmental outcomes of non-isolated PVPC fetuses depend on the accompanying anomaly. [ABSTRACT FROM AUTHOR]

This study examined the relationship between civil servants' work engagement and job-related well-being, and how it is moderated by work motivation. Participant were 496 Chinese civil servants (female = 41.7%; mean age = 40.5 years, SD = 14.14 years, 93.3% were 26-55 years old; managers = 57.5%). The participants completed surveys on work engagement, job-related well-being, and work motivation. Following moderation analyses, results indicated that moderate work engagement is optimal for job-related well-being. Further, work motivation moderated the relationship between work engagement and job-related well-being, such that the relationship was weakened when work motivation was high. In addition, younger age and working at the administrative level were associated with lower job-related well-being. Findings are consistent with the conservation of resources theory in that excessive work engagement reduces job-related well-being, resulting in resource scarcity. High work motivation buffers the effect of work engagement on job-related well-being. [ABSTRACT FROM AUTHOR]

Diamond is a versatile ultimate engineering material that has been recommended for numerous purposes, especially micro mills. Laser-assisted precision grinding is substantiated to be a promising approach for fabricating diamond micro tools. Yet, in practice, the short pulses that render express elimination will deteriorate the flatness of the tool surfaces, bringing about a boost in the risk of edge collapse and a shrink in yield during the subsequent precision grinding. The tactic of ambiance-assisted laser ablation, which introduces an auxiliary gas during the irradiation to promote the ablated domain quality, is proposed in this investigation. Specifically, a raster scanning-based transient temperature distribution simulation is erected to comprehend the ablation mechanism of the chemical vapor deposition (CVD) diamond. Additionally, it can be deduced that the inert nitrogen with high cohesive energy curbs the instantaneous deflagration of oxidation on the Knudsen layer and the activity of dangling bonds that are desorbed at high temperatures. The nitrogen-assisted laser ablation of the diamond sample leads to a maximum dwindling in surface roughness of 33% compared to that with non-ambiance-assisted. Subsequently, the laser-ablated surface optimized by an inert atmosphere is precisely ground with a fine abrasive grinding wheel. The detection of the sharp cutting edge (r β = 1.74 μm) with almost no notch and the ground flank surface with the roughness of 168 nm indicates that accessing the inert auxiliary atmosphere during ablation can enhance the surface quality of the machined diamond and the corresponding grindability. [ABSTRACT FROM AUTHOR]

Microchannel heat sinks (MCHSs) are among the most effective solutions for high-power heating elements; aluminium nitride (AlN) is widely used in various heat sinks owing to its high thermal conductivity. The study aims to investigate the effect of the spoiler column shape, number of rows, and position of the inlet/outlet on the temperature and pressure drop of AlN-based microchannel heat sink using a thermal fluid structure coupling simulation. The results showed that the circular spoiler column had the best dredging effect on the eddy current, which greatly improved the local Nusselt number and heat transfer efficiency. The maximum temperature of the heat sink with circular spoiler columns was 6.53 K lower than that without the spoiler column. The average flow velocity and heat transfer efficiency increased with an increase in the number of spoiler columns and the convective heat transfer area. However, the flow resistance and pressure drop between the inlet and outlet raised. When the inlet and outlet were arranged at the centreline, the flow velocity distribution in the heat sink is more uniform, and the maximum temperature was 160.78 K lower than that on the upper side. Heat transfer experiments were carried out by using three kinds of AlN-based microchannel heat sinks, which was machined by the pickling-assisted laser method. The heat transfer experiments showed that the error between simulation results and test data was less than 0.1%. [ABSTRACT FROM AUTHOR]

To identify the role of digital skill in the skill-biased technological changes caused by artificial intelligence, this study estimates the impacts of displacement risk on occupational wage and employment and examines the moderation effects of digital skill through the occupational data from the U.S. Bureau of Labor Statistics through the methods of fixed-effects modeling, heterogeneity analyzing and moderation effect testing. The results highlight three main points that (1) the displacement risk by artificial intelligence has significantly negative effects on occupational wage and employment, (2) the heterogeneous effects across occupational characteristics are significant, and (3) the digital skill exerts a significant moderation effect to protect against displacement risk. The core policy implication is suggested to emphasize digital skill in education and training across occupations to accommodate job requirements in the future. [ABSTRACT FROM AUTHOR]

The energy budget imbalance at the top of the atmosphere (TOA) and the energy flow in the Earth's system plays an essential role in climate change over the global and regional scales. Under the constraint of observations, the radiative fluxes at TOA have been reconstructed prior to CERES (Clouds and the Earth's Radiant Energy System) between 1985 and 2000. The total atmospheric energy divergence has been mass corrected based on ERA5 (the fifth generation ECMWF ReAnalysis) atmospheric reanalysis by a newly developed method considering the enthalpy removing of the atmospheric water vapor, which avoids inconsistencies due to the residual lateral total mass flux divergence in the atmosphere, ensuring the balances of the freshwater fluxes at the surface. The net surface energy flux (Fs) has been estimated using the residual method based on energy conservation, which is the difference between the net TOA radiative flux and the atmospheric energy tendency and divergence. The Fs is then verified directly and indirectly with observations, and results show that the estimated Fs in North Atlantic is superior to those from model simulations. This paper gives a brief review of the progress in the estimation of the observed energy flow in the Earth system, discusses some caveats of the existing method, and provides some suggestions for the improvements of the aforementioned data sets. [ABSTRACT FROM AUTHOR]

Fluid-attenuated inversion recovery vascular hyperintensity (FVH) is frequently observed in patients with acute ischemic stroke (AIS). FVH is associated with functional outcome at 3 months in AIS patients receiving endovascular thrombectomy. In the present study, we assessed whether FVH predicted early neurological deterioration (END) and hemorrhagic transformation (HT) within 72 h in AIS patients receiving endovascular thrombectomy. We retrospectively analyzed 104 patients with acute internal-carotid-artery or proximal middle-cerebral-artery occlusion within 16 h after symptom onset. Before thrombectomy, all patients underwent brain magnetic resonance imaging. END was defined as an increase of 4 points or more from baseline National Institutes of Health Stroke Scale (NIHSS) during 72 h following onset. HT was assessed by brain computed tomography. Statistical analyses were performed to predict END and HT. The proportion of high FVH score, high American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN/SIR) grade in non-END group was higher than that in END group (p < 0.001, p < 0.001, respectively). FVH score was positively correlated with ASITN/SIR grade (r = 0.461, p < 0.001). FVH score was a predictor factor for END (adjusted OR, 13.552; 95% CI, 2.408–76.260; p = 0.003), while FVH score was not a predictor factor for HT. Furthermore, NIHSS at admission (adjusted OR, 1.112; 95% CI, 1.006–1.228; p = 0.038) and high-density lipoprotein cholesterol (adjusted OR, 18.865; 95% CI, 2.998–118.683; p = 0.002) were predictor factors for HT. To assess FVH score before thrombectomy might be useful for predicting END in AIS patients receiving endovascular thrombectomy. [ABSTRACT FROM AUTHOR]

Artificial graft serves as the primary grafts used in the clinical management of sports-related injuries. Until now, optimizing its graft-host integration remains a great challenge due to the excessive inflammatory response during the inflammatory phase, coupled with an absence of tissue-inductive capacity during the regeneration phase. Here, a multi-layered regenerated silk fibroin (RSF) coating loaded with curcumin (Cur) and Zn2+ on the surface of the PET grafts (Cur@Zn2+@PET) was designed and fabricated for providing time-matched regulation specifically tailored to address issues arising at both inflammatory and regeneration phases, respectively. The release of Cur and Zn2+ from the Cur@Zn2+@PET followed a time-programmed pattern in vitro. Specifically, cellular assays revealed that Cur@Zn2+@PET initially released Cur during the inflammatory phase, thereby markedly inhibit the expression of inflammatory cytokines TNF-a and IL-1β. Meanwhile, a significant release of Zn2+ was major part during the regeneration phase, serving to induce the osteogenic differentiation of rBMSC. Furthermore, rat model of anterior cruciate ligament reconstruction (ACLR) showed that through time-programmed drug release, Cur@Zn2+@PET could suppress the formation of fibrous interface (FI) caused by inflammatory response, combined with significant new bone (NB) formation during regeneration phase. Consequently, the implementation of the Cur@Zn2+@PET characterized by its time-programmed release patterns hold considerable promise for improving graft-host integration for sports-related injuries. Dual-loaded multi-layered RSF coating with curcumin and Zn2+ on PET grafts, which followed a time-programmed pattern of drugs release, could intervene anti-inflammatory and tissue regeneration in a time-matched way, and ultimately improve graft-host integration. [Display omitted] • Time-programmed drug release system by multi-layered RSF coating was designed on the surface of the PET grafts • The system could deliver corresponding therapeutic drug in line with pathophysiological rhythms of graft-host integration. • This system successfully achieved a superior quality, remarkably efficient integration of the graft and host. [ABSTRACT FROM AUTHOR]

The effects of CH3COOH and Na2SO3 pretreatment on the structural properties and hydrolyzability of fast-growing Paulownia elongate were investigated. Acetic acid increased cellulose's crystallinity and hydrolyzability when combined with alkaline sodium sulfite and sodium hydroxide. The cellulose content increased by 21%, the lignin content decreased by 6%, and the product showed better enzymatic digestibility. With a cellulase dose of 30 FPU/g DM, after 72 h hydrolysis, the hydrolysis yields of glucose and xylose were 78% and 83%, respectively, which were 51% and 69% higher than those of untreated materials. When the enzyme dosage was 20 FPU/g DM, after 72 h hydrolysis, the hydrolysis yields of glucose and xylose were 74% and 79%, respectively. The high hydrolyzability, low enzyme loading, and high hydrolysis yield demonstrate the potential of the proposed system for producing platform sugars from fast-growing Paulownia elongate. [ABSTRACT FROM AUTHOR]

Aluminium nitride high-temperature co-fired ceramic (AlN HTCC) substrate is a preferred electronic packaging material. It displays a low thermal expansion coefficient, low dielectric constant, low dielectric loss, and high thermal conductivity at a high frequency. It can also prefabricate the circuit inside. Considering the need to increase the specific surface area of AlN HTCC substrates and thereby enhance the heat dissipation performance, a rapid fabrication method involving chemically assisted laser ablation is proposed to machine microstructures on AlN HTCC substrates. The influence of power, atmosphere, and other factors on the ablation quality of AlN HTCC substrates was explored on this basis. The main component of the ablation products was Al in an Ar atmosphere. However, the modification layers in N 2 and O 2 atmospheres were composed of multiple components including Al, AlN, and Al 2 O 3. The accuracy of the top and bottom widths of the microgrooves in the Ar atmosphere was higher than those for the N 2 and O 2 atmospheres. However, the variation of atmosphere had a negligible effect on the ablation depth. When the laser-energy density was 100 J/mm2 and the scanning distance was 10 μm, the ablation depth increased linearly from 150 μm to 350 μm as the laser power increased from 8 W to 20 W. The deviation in laser-energy density was established to predict the surface roughness and optimise the laser parameters. It was observed that the surface roughness increased with an increase in the deviation in laser-energy density. The surface roughness could be reduced by two–three times from that obtained by laser ablation with optimisation. [ABSTRACT FROM AUTHOR]

Digital inline holography is an amazingly simple and effective approach for 3D imaging, to which particle tracking velocimetry is of particular interest. Conventional digital holographic particle tracking velocimetry techniques are computationally separated in particle and flow reconstruction, plus the expensive computations. Usually, the particle volumes are recovered first, from which fluid flows are computed. Without iterative reconstructions, This sequential space–time process lacks accuracy. This paper presents a joint optimization framework for digital holographic particle tracking velocimetry: particle volumes and fluid flows are reconstructed jointly in a higher space–time dimension, enabling faster convergence and better reconstruction quality of both fluid flow and particle volumes within a few minutes on modern GPUs. Synthetic and experimental results are presented to show the efficiency of the proposed technique. [ABSTRACT FROM AUTHOR]

SKD11 is widely used in manufacturing die. With the development of industrial level, the size of the die is further reduced, and the difficult processing problem of high aspect ratio (HAR) micro-structures is exposed. Micro-milling is a suitable method for machining HAR micro-structures; however, the inevitable generation of burrs deteriorates the machined surface. Previous studies have mostly focused on the burr formation process of shallow grooves but have ignored HAR grooves. This paper investigated the burr formation mechanism in HAR (2:1) grooves on harden steel (SKD11). Due to the fact that the burr formation process was difficult to be observed in the actual micro-milling process, a finite element model was established. A corresponding experimental research was conducted, which revealed a good consistency between simulation and experimental results. Moreover, a new burr type was formed on the sidewall of the HAR groove, which was transformed from top burrs and was named as side burr. The results demonstrated that the chip flow on the rake face of the micro-mill was hindered by the sidewall, which caused chip crumbling, chip accumulation, and surface scraping, seriously affecting the burr formation mechanism. This paper revealed the burr formation mechanism for HAR grooves on SKD11, which provides basic data for manufacturing die with complex structure and small size. [ABSTRACT FROM AUTHOR]

Aluminium nitride (AlN) ceramic is a typically difficult-to-machine material used in electronic packaging. Laser and chemical milling enhanced micro milling (LCMEM), a high-quality and efficient processing method for AlN, is proposed in this study. Rough machining is completed by repeated alternating laser ablation and chemical removal; the final finish is achieved by micro milling (MM). To achieve precise laser and chemical milling parameters based on the target structure, a laser and chemical milling (LCM) prediction model is established and verified; this can be used to predict the morphology of the grooves after LCM. The change trend of the grooves after LCM with the laser parameters is investigated. It was found that LCMEM can improve the surface quality by 60 %, and an optimal finishing surface with a surface roughness Ra value of 54 nm can be obtained when the feed per tooth is 0.4 µm/z. Lastly, this study uses LCMEM to produce a high aspect ratio groove with aspect ratio of 2.5 and depth of 1250 µm. Compared with conventional MM, LCMEM reduces the allowance of MM by 71.95 %, improves the groove accuracy, and reduces tool wear. [ABSTRACT FROM AUTHOR]

A major driving force behind China's low-carbon, environmentally friendly development of agriculture and the accomplishment of the "dual-carbon" goal is the digital transformation of rural areas. In this study, on the basis of clarifying the degree of rural digitization and agricultural carbon emissions efficiency in China from 2010 to 2021, the degree of coupled coordination and the spatiotemporal pattern characteristics between the two are examined using the coupled coordination model. Then, the influencing factors are analyzed in depth using the spatial Durbin model. Our findings reveal that, first, in terms of the degree of rural digitization, the index increases overall and the spatial imbalance is obvious, with a spatial distribution pattern of "high in the east and low in the west". Regarding the efficiency of agricultural carbon emissions, there is an overall "N-shaped" change, which is mainly influenced by technological progress in agricultural production, and the regional annual averages are, in descending order, the Western, Eastern, Northeastern, and Central regions, with obvious regional differences. Second, the coupling coordination index shows a fluctuating upward trend, from "extreme disorder" to "high-level coordination". Furthermore, there are obvious regional characteristics. The regional growth rates are, in descending order, the Western, Eastern, Central, and Northeastern regions. Third, coupling coordination is jointly influenced by a variety of factors, including government input, educational level, industrial structure, energy use, urbanization rate, living standards, driving temporal patterns, and regional differences. This study not only helps to clarify the relationship between the two, offering a reference for the realization of the "dual-carbon" goal, but also broadens the concepts of the low-carbon and environmentally friendly development of agriculture. [ABSTRACT FROM AUTHOR]

Background: The influenza A virus is the primary cause of respiratory infections and poses a global health risk. Pudilan Xiaoyan oral liquid (PDL) exhibits anti-inflammatory and immunomodulatory properties. PDL is commonly employed in clinical practice to manage upper respiratory tract infections. However, there is still much to uncover regarding its potential therapeutic mechanism. Methods: Institute of cancer research mice were infected with influenza A virus via nasal drip. The general state of the mice, lung index, and lung index inhibition rate were used to evaluate the efficacy of PDL. Enzyme-linked immunosorbent assay, western blotting, and immunohistochemistry were used to observe the presence of proteins and cytokines in the lung tissue. Apoptosis was evaluated using the TUNEL assay. Results: PDL improved the mental state of influenza A virus-infected mice, reduced the lung index, and inhibited viral replication. The expression of interleukin-1β and tumor necrosis factor-α were decreased, whereas the expression of interleukin-10 in the lung tissue was increased due to PDL treatment. In addition, PDL treatment modulated Toll-like receptor 4 and MyD88 expressions in the lung tissues. PDL significantly reduced apoptosis and decreased cleaved caspase-3 and PARP levels, whereas increased B-cell lymphoma-2 expression in the lung tissue. Notably, the moderate-dose group of PDL exhibited a more pronounced effect. These findings indicate that PDL exerts a protective effect against pneumonia injury in influenza A virus-infected mice. Conclusion: PDL inhibited the inflammatory response and regulated apoptosis by regulating Toll-like receptor 4 and MyD88 protein expressions, thereby protecting the lung tissue from viral infection-induced lung tissue injury. [ABSTRACT FROM AUTHOR]

High aspect ratio (HAR) structures are widely utilized in diverse applications, including the defense industries, medical treatment, and aerospace. Studies show that the micro-milling has superiorities such as high efficiency and high flexibility over other methods. Currently, the biggest problem of micro-milling is the influence of burrs on the milling performance, which is an enormous challenge to remove. In the present study, numerical simulations through the finite element method (FEM) and experiments are carried out to optimize cutting parameters of the specimen made of Cr12MoV alloy. Moreover, an improved constitutive model is proposed by considering the size effect of the micro-milling. The proposed model is based on the J-C constitutive model, and it is concluded that the cutting force error is 4.6% through the comparison of experiment and FEM, which further proves the convergence of the improved constitutive model. It is also found that the side burr of HAR slots and the top burr of shallow slots are the biggest factors affecting the surface quality. The depth of cut (DoC) affects the maximum bending angle of the tool, the feed per tooth (FpT) affects the size of the unremoved area, and the spindle speed (SpS) affects the dynamic balance of the micro-mill, through the exploration of the above cutting parameters which can effectively improve the cutting state of the tool and finally achieve the purpose of curbing burr. [ABSTRACT FROM AUTHOR]

Due to the exceptional thermal conductivity and material hardness, CVD diamonds have been ideal materials for cutting tools; however, the specific properties of CVD diamonds vary with the grain size. An experimental study was carried out on chemical vapor deposition (CVD) diamonds with varying grain sizes in laser processing. This study aims to analyze the behavior of polycrystalline CVD diamonds under different thermal processing based on its thermal conductivity model. The pit formed under a single laser pulse on the material with a small grain size is shallow and tiny, because of its small thermal conductivity, a value calculated using the established model. The results show that for laser-machined surface, the material with a small grain size can obtain a better machined surface but a small material-removal depth; conversely, material with a large grain size provided opposite experimental results. Additionally, reasonable laser parameters achieved the desired material-removal depth of up to or even exceeding 180 μm and surface roughness Sa as low as 0.2 μm. Overall, both the grain sizes of polycrystalline CVD diamonds and laser parameters affect the machining result. However, there are considerable obstacles in simultaneously achieving a good surface and massive material removal. Hence, a tradeoff between the two aspects is essential in an actual machining process, and this study provides some useful guidance to practitioners and academicians. [ABSTRACT FROM AUTHOR]

Tool wear monitoring is deemed as an essential technology of the intelligent manufacturing to guarantee the processing quality and improve the machining efficiency. In this paper, a prediction model based on adaptive particle swarm optimization (APSO) algorithm and least squares support vector machine (LS-SVM) algorithm is proposed for the recognition of drill wear. Cutting force signal and vibration signal are used for tool wear monitoring. And these signals are preprocessed through wavelet threshold de-noising algorithm. Multiple signal feature extraction methods are carried out to process the sample data related to drill wear status. The mean absolute error of the tool wear recognition model is 0.91%, better than the standard LS-SVM algorithm under the same condition. [ABSTRACT FROM AUTHOR]

A series of aromatic or long-chain chrysin derivatives (1–10) were synthesized by esterification of chrysin and acyl chloride. The chemical structures of these compounds were determined by mass spectrum (MS), 1H NMR, and 13C NMR spectra. Though aromatic chrysin derivatives (1–9) with a rigid structure were hard to dissolve in common organic solvents, the long-chain chrysin derivative (10) with a flexible structure had better solubility, and its anticancer activity (IC50 = 14.79 μmol/L) against liver cancer cell lines was 5.4 times better than chrysin (IC50 = 74.97 μmol/L), which showed superposition of pharmacological activity. [ABSTRACT FROM AUTHOR]

BACKGROUND: Bone marrow adipocytes are derived from mesenchymal stem cells. It has been found that mesenchymal stem cells can also differentiate into osteoblasts, chondrocytes and myocytes. Current results show that marrow adipose tissue could negatively regulate the osteogenesis process because mesenchymal stem cells can differentiate into adipocytes in priority. Exercise promotes bone formation and plays an important role in preventing fractures. Exercise, diet, and rosiglitazone are shown to affect the generation of marrow adipose tissue, but the relationship between them is not clear. OBJECTIVE: To summarize the effects of exercise, diet and rosiglitazone on marrow adipose tissue and their relationship with bone mineral density. METHODS: Studies related to exercise regulating marrow adipose tissue published from January 1999 to June 2019 in CNKI, WanFang and PubMed databases were retrieved. The search terms were "marrow adipose tissue, exercise, rosiglitazone, high fat-diet, mesenchymal stem cell" in English and Chinese, respectively. Finally 66 eligible articles were enrolled for analysis. RESULTS AND CONCLUSION: Based on the current research results, exercise can affect the regulation of high-fat diet and rosiglitazone on the formation of bone marrow adipose tissue. Exercise intervention can inhibit the differentiation of mesenchymal stem cells into marrow adipose tissue. In the process of exercise intervention on marrow adipose tissue, there are many other ways participating in the regulation of fat synthesis, lipid absorption, bone metabolism, bone marrow hematopoietic function. Therefore, exercise intervention has an important part in regulating the above metabolic processes. In the future, the specific mechanism of exercise intervention in bone marrow adipose tissue should be further explored to make exercises become an important measure for regulating the above metabolic processes. [ABSTRACT FROM AUTHOR]

[Display omitted] • A strategy for the preparation of carbon nanosheets by electrochemical stripping of precursors by laser induced graphitization was proposed. • The effect of electrochemical stripping on the friction coefficient of carbon nanosheets was studied. • The carbon nanosheets can reduce the relative wear rate of diamond matrix by 4.1–15.4 times. Diamond tools experience severe chemical wear when machining ferrous metals, which hinders their practical applications. In order to improve the wear resistance of diamond cutting tools, in the diamond-graphite strong covalent structure prepared by laser induced solid-phase diffusion, carbon nanosheets (CNS) can be obtained by electrochemical stripping of the graphite layer onto the diamond matrix, which provides a new way to improve the limitations of diamond tools in application. After 14,400 cycles of reciprocating sliding against the GCr15 ball at a normal load of 2–8 N, friction was reduced by 45.9 %–65.6 % with high durability. The oxygen content is reduced by an order of magnitude during this process, suggesting that the CNS can prevent oxidation behavior at the sliding interface. The bare diamond had a relative wear rate of 4.1–15.4 times that of the CNS. It showed competitive inhibition of mechanochemical wear. Our work provides a convenient and green method of preparing in-situ CNS covalently bonded on a diamond surface, extending the way for the prospect of carbon materials. [ABSTRACT FROM AUTHOR]

Diamond and graphene are the most widely used carbon allotropes and offer great potential for developing mechanical, electronic, energy-storage, and sensor applications. Their combination, especially interfacial covalent bonding, can impart excellent properties. However, achieving interfacial covalent bonding with superior performance using flexible and low-power strategies remains challenging. This study developed a novel instantaneous transformation method from diamond to graphene to prepare a new covalent structure of diamond–nano-graphite–graphene (CDGG). That is, a nanosecond-pulse laser induces sp3-to-sp2 instantaneous transformations from diamond to graphite in air, and the subsequent mechanical cleavage overcomes the weak van der Waals forces to achieve the final transformation of graphite to graphene. First, the key factors influencing laser-induced graphitization and mechanical cleavage were investigated, and a covalent carbon structure with multidirectional graphene was obtained. Furthermore, the mechanisms encompassing the lattice transformation, interface relationships, transformation time, and interface bonding were elucidated. The obtained new structure synergized the excellent properties of diamond, nano-graphite, and graphene, exhibiting superior lubrication, mechanochemical wear resistance, durability, and load-capacity. Compared to polished diamond, the obtained structure exhibited a significant decrease in the stable coefficient of friction by 49–59 % and a reduction of more than one order of magnitude in the relative wear rate under high friction against ferrous metals with a normal load of 1–9 N. Even under a heavy load of 100 N, it still exhibited superior lubrication and mechanochemical wear resistance. Finally, the preparation and patterning of covalent carbon structures were achieved on various diamond surfaces with high efficiency, environmental friendliness, and low power. This study is expected to broaden the scope of developing and applying diamond, diamond films, and graphene devices. [Display omitted] • Proposing a novel strategy for an instantaneous formation of covalently bonded graphene on diamond surface. • Generating a new covalent structure of diamond–nano-graphite–graphene (CDGG). • Revealing the mechanisms of lattice transformation, plastic flow, unilateral graphite cleavage, instantaneous transformation. • Effectively inhibiting the mechanochemical wear of the diamond surface and improve the friction state. • Realizing CDGG preparation on various diamond surfaces with high efficiency, environmental friendliness, and patterning. [ABSTRACT FROM AUTHOR]

The CVD diamond material with high wear resistant has been frequently used as the material of micro mills. The laser-based pre-treatment of CVD diamond has been identified as a favorable technique for subsequent precision machining in terms of efficiency and surface quality. This study is aimed to investigate the effect of CVD diamond material on the ablation depth and surface roughness (Sa and Sz) in laser-based machining, so as to improve the overall machined surface quality. Controlling ablation depth and high surface finish are the key indicator for the follow-up accurate treatment. In addition, the energy density distribution (EDD) model was established to better explain the microstructural changes in CVD diamond material after performing the laser machining. Through EDD model, the variation in ablation depth and surface roughness were evaluated at different laser parametric levels. The results showed that the ablation depth and surface roughness of EDD model are basically consistent with the experimental values. Moreover, at the same total energy density, the ablation depth and surface roughness Sa and Sz values are lower under the condition of low average laser power, large filling pitch and small laser scanning speed. In a nutshell, minimum surface roughness and a controlled ablation depth are achieved on CVD diamond by adjusting laser parameters. • The energy density distribution model is established to explain the changes of ablation depth and surface roughness. • The ablation depth increases when power increases, and decreases when filling pitch and scanning speed increase. • Surface roughness values increase when power increases, and decease when filling pitch andscanning speed increase. • Small power, large filling pitch and scanning speed are benefit to surface quality but harmful to the material ablation. [ABSTRACT FROM AUTHOR]

Juvenile xanthogranuloma (JXG) is a benign, self-limiting histiocytic disorder of infancy and early childhood, usually presented as a single or multiple cutaneous lesions. The central nervous system is rarely affected by JXG. There were only a few reports of intracranial JXG cases which described its features on MR spectroscopy (MRS) and diffusion-weighted imaging (DWI), but its features on susceptibility-weighted imaging (SWI) and perfusion-weighted imaging (PWI) have not been reported yet. Here, we reported an intracranial JXG case which underwent multimodal MRI examinations including DWI, SWI, and PWI. The multimodal MRI provided a thorough insight into this disease and we found that intense enhancement and high perfusion may be important clues for the diagnosis. [ABSTRACT FROM AUTHOR]

Highlights • A new mechanistic model is established to determine the ploughing force in micro end-milling of soft-brittle crystals. • The ploughing force can be controlled less than shearing force with the suitable cutting edge radius and feed rate. • The increased energy consumption is mainly caused by the ploughing effect, especially for the large cutting edge radius. • The small cutting edge radius or large cutting edge radius (under the condition that the feed per tooth is nearly equal to cutting edge radius) are recommended. Abstract The ploughing force can be assigned to supervisory control of the tool wearing and machining process on-line in micro milling, for the reason that the ploughing force is closely related with the processed surface quality and radius of cutting edge. A new theoretical model is established to determine the ploughing force in micro milling of crystals with soft-brittle characters in consideration of the cutting edge roundness, and it is verified by Finite Element Method. The ploughing force decreases quickly with an decrease of the cutting edge roundness, and it can be controlled to be less than the shearing force, which helps for obtaining a good machined surface quality, under the condition that the radius of cutting edge is less than 2.8 μm or the feed speed is larger than 5 μ m/z when the radius of cutting edge is larger than 4.2 μm. Meanwhile, a large feed speed would bring heavy tool traces on the processed surface of soft-brittle crystals, destroying the processed quality. The energy consumption is researched by investigating the specific cutting force, showing that the energy consumption has a sharp increase with a small feed speed. The energy consumption is mainly caused by the ploughing effect, especially for tools with blunt cutting edge. Therefore, both the micro mill with sharp tool edge or blunt tool edge (under the cutting condition that the feed speed almost have equal value to the radius of cutting edge) are highly recommended for micro end milling of soft-brittle crystals. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Abstract Facing the challenge of huge population and prominent contradiction between land supply and demand in China, improving the land use efficiency will be a crucial way to solve this contradiction. Based on microscopic sampling data for 703 forestland plots, maintained by 290 rural households, in 30 villages in Liaoning province, and using forestland plots as the decision making unit, the influencing factors of forestland production efficiency were analysed by means of econometric analysis. The results show that increasing household labour and mechanical services helps to improve the production efficiency of forestland. Rural households' willingness to transfer forestland is weak and the frequency of forestland transfers is relatively low; without action, forestland transfers can be expected to continue to fail to fulfil their potential in stimulating production efficiency. Collective forestland (predominantly public welfare forest) made a limited contribution to forestry production efficiency. From the perspective of property security, although the certification work has more or less been implemented, the factors of property rights certificates, management duration and forestland rights exerted no significant effect on forestland production efficiency. The security and stability of households' forest property rights urgently need to be consolidated. Moreover, although forest insurance has an important effect on forestland production efficiency, the proportion of households purchasing forest insurance is still low and needs to be improved. The development of forest rights mortgage loans is blocked, and these have not played a significant role in forestland production efficiency to date. Forestry subsidy mechanisms were not sound, and non-subsidized forestland production efficiency was far higher than that of subsidized forest. As such, we conclude that forestry subsidies have failed to play a positive role in increasing efficiency. In order to promote forestland production efficiency and the sustainable growth of forestry, it is essential that emphasis be placed on forestland inputs, plot characteristics, property security and policy subsidies for micro-plots. [ABSTRACT FROM AUTHOR]

The accurate determination of the tool-wear state helps workers maximise tool utilisation while reducing waste. It also ensures the machining quality and improves the machining efficiency. This study proposed a deep learning network based on the self-attention mechanism that enabled global modeling and long-term dependence for better tool wear state recognition by cutting signals. The Hierarchical Temporal Transformer Network (HTT-Net) was constructed by improving the Swin Transformer backbone network to enable the global modeling of the input temporal sequence signal. The token merging layer is used to build a hierarchical feature map, that enables the model to continuously increase the receptive field and improve its global modeling capability. Self-attention calculation is performed on the temporal sequence data partition window, which reduces the complexity of the model from a quadratic into a linear form of the sequence length. The shifted window enables information interaction between non-overlapping windows, which can improve the global modeling capability of the model. PHM2010 public cutting data and TC4 milling data were used for model training and test. The results showed that the tool wear state recognition capability of HTT-Net on the PHM2010 dataset outperformed the models in existing studies, with up to 16.13% improvement in recognition accuracy on the relevant dataset. The recognition accuracy on the TC4 milling dataset can reach 98.87%, which further verified the actual application capability of the model. At last, The Q-Q graph analysis verified that the model had strong robustness and stability, and the ablation experiment verified that each module of the model had positive gain on the recognition results. [ABSTRACT FROM AUTHOR]

A novel ultrasound-based approach for the deposition of an octacalcium phosphate (OCP) and nanocrystalline apatite (ncAp)-based coating on the magnesium alloy AZ31 as a biodegradable implant material is established. The studies consider both the structural analysis and the resulting corrosion protection and correlate the related findings with cytocompatibility. The ultrasound-based approach is shown to lead to the deposition of an OCP and ncAp-based coating with a trilayer structure on AZ31. The coatings consist of two inner compact layers and an open porous top layer. The formation of the functional OCP/ncAp coating and deposition on the AZ31 surface take place within minutes in a single processing step and do not require any pre-heating, mediators or post-deposition treatment for the achievement of corrosion protection and cytocompatibility. The obtained coatings were characterized by means of FTIR and Raman spectroscopy as well as FE-SEM and X-ray crystallography. Electrochemical impedance spectroscopy revealed corrosion inhibition especially in the initial phase after immersion in physiological electrolyte. Moreover, this corrosion protection resulted in a strongly improved cytocompatibility of AZ31 as verified by in vitro viability tests using human mesenchymal stromal cells. [ABSTRACT FROM AUTHOR]

The energy levels and binding energies of a hydrogenic impurity in GaAs spherical quantum dots with radiusRare calculated by the finite difference method. The system is assumed to have an infinite confining potential well with radiusR, which can be viewed as a hard wall boundary condition. The parabolicity of the conduction band profile for GaAs material can be viewed as a parabolic potential well. The energy levels and binding energies are depended dramatically on the radius of the quantum dot and the parabolic potential well. The results show that parabolic potential can remarkably alter the energy level ordering and binding energy level ordering of hydrogenic impurity states for the quantum dot with a smaller radiusR. [ABSTRACT FROM AUTHOR]

Many critics view deontology (focusing largely on the merits of an action itself) and utilitarianism (evaluation of an action based on its projected consequences) as rival approaches to ethical decision making. This survey of public relations students at three universities in the United States and one each in Hong Kong and mainland China suggest that, as various theorists propose, many people adhere to both schools of thought, with utilitarianism being the dominant view overall. Furthermore, belief in both schools appears to correlate with high-minded ethical thinking as measured by assessments of several hypothetical ethical decisions. Implications for teaching are suggested. [ABSTRACT FROM AUTHOR]

Submerged fermentation is promising for producing secondary metabolites of Inonotus obliquus, a folk medicine to treat cancer and other diseases. However, there limited progress work in strain selection or process optimization in order to enhance production of its bioactive metabolites. In this work, a new Inonotus obliquus strain was isolated from the sclerotia collected in Belarus, which was identified by ITS sequencing and phylogenetic analysis. The dissolved oxygen (DO) condition was optimized, it showed that 50% DO level facilitated secondary metabolites production. Finally, a glucose fed-batch integrated DO control strategy was developed by feeding 10 g/L glucose when residual sugar decreased to 10 g/L, while controlling DO level at 50%. The biomass, polysaccharide, triterpenoids and inotodiol production enhanced by 52%, 31%, 54% and 65%, respectively. This study demonstrated that the new strain shown good fermentation property. Glucose fed-batch integrated DO control strategy effectively enhanced secondary metabolites production in fermentation of Inonotus obliquus . [ABSTRACT FROM AUTHOR]

Micro-milling is a promising approach to repair the micro-defects on the surface of potassium dihydrogen phosphate (KDP) crystal. However, KDP crystal is difficult to machine due to its properties of soft-brittle and easy deliquescence. This study investigates the minimum undeformed chip thickness h m and the size effect in micro end-milling of KDP crystal by comprehensively analyzing cutting force, specific cutting force and machined surface quality. A model of the chip formation, which is capable of connecting the minimum undeformed chip thickness, the undeformed chip thickness and the periodicity of cutting force together, is developed to predict the value of minimum undeformed chip thickness. The normalized minimum undeformed chip thickness λ e in terms of the ratio of the minimum undeformed chip thickness to the cutting edge radius r e , is estimated to be 0.43 ≤ λ e ≤ 0.48. The significantly non-proportional increase of specific cutting force indicates the existence of size effects when the ratio of feed per tooth to cutting edge radius f t / r e is less than 0.7. The machined surface quality also reflects severe size effect by the phenomenon that the micro cracks and brittle pits appear on the groove base, and the value of surface roughness R a is large when the ratio f t / r e is less than 0.5. Furthermore, the surface quality deteriorates and the brittle cutting appears when the ratio f t / r e is much larger than 1 which seems similar to macro-milling. The perfect machined surface with almost no ploughing effect and brittle cutting is achieved at a ratio f t / r e of 0.7. Therefore, a feed per tooth, slightly larger than the minimum undeformed chip thickness but smaller than cutting edge radius, is recommended for micro-milling of KDP crystal or soft-brittle crystal. [ABSTRACT FROM AUTHOR]

The forestry industry in China is undergoing a transformation, with integrated development and improved productivity seen as crucial to achieving efficient and healthy growth. In this study, we used the Herfindahl index method, coupling Super-CCR model, Malmquist index method, and spatial Durbin model to measure and analyze the level of forestry industry integration, total factor productivity of the forestry industry, and effects of the former on the latter of each province in China from 2005 to 2019. Results showed that, first, the level of forestry industry integration increased, but there were differences in the Northeast-Central-West-East cascade. The integration level of the forestry industry in each province was mostly at the moderate or medium-high integration stage. Second, the total factor productivity of the forestry industry increased overall, with the Central, Eastern, Western, and Northeastern regions having regional annual average values from high to low, respectively. The main driving force for the advancement of technology was the sub-index. Third, forestry industry integration played a major role in promoting total factor productivity of the forestry industry by promoting pure technical efficiency. Forestry industry integration not only affected the improvement of total factor productivity of forestry industry in the region but also had a spatial spillover effect on adjacent areas. Efforts to boost integrated forestry industry development will enhance total factor productivity growth by leveraging high-productivity agglomeration effects, strengthening regional communication and cooperation, and promoting integrated forestry industry development with adjacent regions. This work may contribute to understanding this relationship and to creating effective regional forestry development policies. [ABSTRACT FROM AUTHOR]

Potassium dihydrogen phosphate (KH 2 PO 4 or KDP) crystal is a typical soft-brittle optical crystal, and the size effect and brittle cutting mode are easy to appear in micro ball end-milling of KDP crystal. In this paper, micro-grooving experiments are conducted to study the size effect and brittle cutting in micro ball end-milling of KDP crystal with different feed rate and depth of cut. The cutting force, machined groove base quality and chip morphology are collected and analyzed carefully. The size effect is discovered by the phenomena of the existence of oscillations and relaxations in cutting force and hyper-proportional increase of specific cutting force, when the ratio of feed per tooth to cutting edge radius f t / r e is less than 1. While the brittle cutting mode is detected through the existence of sharp fluctuations in cutting force and cracks on the groove base when the ratio f t / r e is larger than 2. From the further comprehensive analysis of cutting force, specific cutting force, machined groove base quality and chip morphology, the cutting parameters with ratios of the maximum undeformed chip thickness in one cutting circle to cutting edge radius h max / r e around 0.14, 0.2 and 0.4 are regarded as size effect, optimal and brittle cutting points, respectively. The size effect, ductile cutting and brittle cutting zones are divided by the size effect and brittle cutting boundaries (points). Among the optimal points, the depth of cut of 2 μm with the ratio f t / r e of 1 is the optimal cutting parameter for micro ball end-milling of KDP crystal. [ABSTRACT FROM AUTHOR]

The delamination of an epoxy-adhesive film from a zinc coated steel substrate was studied by means of the electrochemical Height Regulated Scanning Kelvin Probe Blister Test (HR-SKP-BT 1 1 HR-SKP-BT: Height Regulated Scanning Kelvin Probe Blister Test. ) under controlled atmospheric conditions, applied pressure and interfacial electrode potential. The experimental studies focused on the analysis of the critical environmental water activity that leads to a corrosive delamination process under applied mechanical load and the analysis of the corrosion and delamination mechanisms at the front of delamination. The influence of applied pressure and relative humidity on the increase in the maximum blister height and the delamination rate was measured under constant polarization of the defect. 90° peel-tests were performed in order to correlate the water activity with the resulting peel force. The corrosion products that formed across the delamination front were analyzed by Raman microscopy. Through these HR-SKP-BT studies, a critical value was found for relative humidity for the delamination process. A transition zone was detected in which electrochemical degradation precedes mechanical delamination. In addition to the experimental studies, the critical energy release rates of the blister were calculated in finite element (FE 2 2 FE: Finite Element. ) simulations so as to enable a better understanding of the delamination of adhesives on metal surfaces. The combined experimental and theoretical studies show that the delamination process is controlled by the interfacial electrochemical reactions at the delamination front and that a transition area of few hundred micrometers exists in which the adhesion strength is lowered by the cathodic oxygen reduction process to a value which can be overcome by the mechanical stress in this area. [ABSTRACT FROM AUTHOR]

The antioxidative response mediated by transcription factor NRF2 is thought to be a pivotal cellular defense system against various extrinsic stresses. It has been reported that activation of the NRF2 pathway confers cells with resistance to ionizing radiation-induced damage. However, the underlying mechanism remains largely unknown. In the current research, it was found that α-particle radiation has the ability to stimulate NRF2 expression in human osteosarcoma U-2 OS cells. Knockdown of cellular NRF2 level by shRNA-mediated gene silencing decreased the survival rate, increased the micronucleus formation rate and apoptosis rate in irradiated cells. Consistently, knockdown of NRF2 resulted in decreased expression of p65 and Bcl-2, and increased expression of p53 and Bax. Besides, it was observed that increased expression of NRF2 was partially dependent on radiation induced phosphorylation of ERK 1/2. Further results showed that radiation promoted autophagy flux which leads to the enhanced phosphorylation of ERK 1/2, as evidenced by the resultls that knockdown of ATG5 (Autophagy protein 5) gene by shRNA suppressed both radiation induced ERK 1/2 phosphorylation and NRF2 upregulation. Based on these results, it is proposed that attenuation of NRF2 antioxidative pathway can sensitize U-2 OS cells to radiation, where NRF2 antioxidative response is regulated by autophagy mediated activation of ERK 1/2 kinases. [ABSTRACT FROM AUTHOR]

This study is a mega-analysis to reconcile Carl Botan's Grand Strategy Models for strategic communication with actual cases. Invoking Botan's six-factor and four grand-strategy models proposition as an analytical framework, this study conducted a multi-case analysis on selected Chinese and international brands during the period of 2005-2014. Its preliminary findings revealed significant differences between Chinese and international corporations in applying strategic communication to brand crisis communication and management. The results also showed that, first, Chinese corporations tended to have lower level of understanding on all the six dimensions of grand strategies; second, they were more likely to rely on resistant strategy (70%), with 30% on intransigent strategy, but NONE on cooperative strategy and integrative strategy. This study hence asserts that the differences between the Chinese and international corporations in handling brand crises via strategic communication are, first and foremost, rooted in their different values attached to brands; second, effected by their different attitudes toward publics and competencies in issue management; and third, as a result of their different maturity level in crisis management. [ABSTRACT FROM AUTHOR]

Background: The flowers of Carthamus tinctorius L. are widely used in traditional Chinese medicine to treat cerebrovascular and cardiovascular diseases. Hydroxysafflor yellow A (HSYA), the main constituent of C. tinctorius L. flowers, is known for its multiple biological activities. The present study investigated the effects of HSYA on angiogenesis in vitro and in a mouse hindlimb ischemia model. Methods: Using human umbilical vein endothelial cells (HUVEC) in vitro and a mouse hindlimb ischemia model in vivo, the angiogenic role of HSYA was evaluated. Results: HSYA significantly increased the capillary-like tube formation and migration of HUVEC. HSYA not only induced a rise in the expression of angiopoietin 1 and Tie-2 but it also increased phosphorylation of Tie- 2, Akt, and extracellular signal-regulated kinase 1/2. Furthermore, an anti-Tie-2 neutralizing antibody significantly inhibited HSYA-induced HUVEC tube formation and migration. In vivo, the recovery of perfusion of ischemic hindlimb tissue after femoral artery interruption was significantly increased in HSYA-treated mice compared to vehicle controls. Consistent with these results, the arteriole and capillary densities in ischemic gastrocnemius muscles were significantly increased in HSYA-treated mice. Conclusions: These results indicate the potential utility of HSYA for the treatment of ischemic diseases. [ABSTRACT FROM AUTHOR]

The energy levels and binding energies of hydrogenic impurity associated with the ground state and some low-lying states in GaAs/AlGaAs core/shell quantum dots are theoretically studied by using the finite difference method. It is shown that energy levels and binding energies are depended dramatically on the size of the quantum dot due to quantum size effect. The change of the level ordering for hydrogenic impurity can be found and then to cause the corresponding changes in the binding energies, which can be adjusted by the radius of the quantum dot. Based on the analysis of these energy levels, the third-harmonic generation susceptibility in this quantum dot with (or without) impurity is investigated by using the compact-density-matrix approach. The results show that the third harmonic generation susceptibility obtained in the two cases can reach the magnitude of ∼10 −7 m 2 V −2 by choosing a large radius of quantum dot. For the large quantum dot with impurity, it is found that the third-harmonic generation susceptibility can be effectively enhanced about 1.3 ∼ 1.5 times than the case regardless of the impurity. Finally, the resonant peak and its corresponding to resonant energy are also taken into account. [ABSTRACT FROM AUTHOR]

LiF crystal is a kind of soft brittle crystal used as optical functional material. However, severe wear, especially chemical wear for micro cemented carbide end mill which was encountered at the early stage of micro milling process, was firstly found in this paper. Wear regularities and mechanisms were revealed through micro milling experiments and later analysis. Firstly, micro milling of LiF crystal was conducted, and the effect of spindle speed and feed per tooth on the tool wear and surface roughness of the machined workpiece was studied. Then, main wear patterns and their respective mechanisms were analyzed through the SEM micrographs and energy spectrum analysis. Further component analysis and contrast experiments between fused silica and LiF crystal revealed that chemical reactions, especially oxidation reactions should be occurred. Subsequent experiments proved that micro cubic boron nitride (CBN) end mill was suitable for the milling of LiF crystal and the roughness value of the machined surface was still below 30 nm even after a long cutting distance. The paper can provide guidance for tool material election for milling LiF crystal. [ABSTRACT FROM AUTHOR]

Electric field effect on the second-order nonlinear optical properties in semiparabolic quantum wells are studied theoretically. Both the second-harmonic generation susceptibility and nonlinear optical rectification depend dramatically on the direction and the strength of the electric field. Numerical results show that both the second-harmonic generation susceptibility and nonlinear optical rectification are always weakened as the electric field increases where the direction of the electric field is along the growth direction of the quantum wells, which is in contrast to the conventional case. However, the second-harmonic generation susceptibility is weakened, but the nonlinear optical rectification is strengthened as the electric field increases where the direction of the electric field is against the growth direction of the quantum wells. Also it is the blue (or red) shift of the resonance that is induced by increasing of the electric field when the direction of the electric field is along (or against) the growth direction of the quantum wells. Finally, the resonant peak and its corresponding to the resonant energy are also taken into account. [ABSTRACT FROM AUTHOR]

Micro-milling is a promising approach to repair the micro-defects on the surface of KH 2 PO 4 (KDP) crystal. The geometrical parameters of micro ball end mill will greatly influence the repairing process as a result of the soft brittle properties of KDP crystal. Two types of double-edged micro ball end mills were designed and a three-dimensional finite element (FE) model was established to simulate the micro milling process of KDP crystal, which was validated by the milling experiments. The rake angle of −45°, the relief angle of 45° and the cutting edge radius of 1.5–2 μm were suggested to be the optimal geometrical parameters, whereas the rake angle of −25° and the relief angle of 9° were optimal just for micro ball end mill of Type I, the configuration with the rake angles ranging from 0° to 35°, by fully considering the cutting force, and the stress–strain distribution over the entire tool and the cutting zone in the simulation. Moreover, the micro polycrystalline diamond (PCD) ball end mills adopting the obtained optimal parameters were fabricated by wire electro-discharge machining (WEDM) and grinding techniques, with the average surface roughness Ra of tool rake face and tool flank face ∼0.10 μm, and the cutting edge radius of the tool ∼1.6 μm. The influence of tool's geometrical parameters on the finished surface quality was verified by the cutting experiments, and the tool with symmetric structure was found to have a better cutting performance. The repairing outlines with Ra of 31.3 nm were processed by the self-fabricated tool, which could successfully hold the growth of unstable damage sites on KDP crystal. [ABSTRACT FROM AUTHOR]

Understanding the responses of soil erosion processes to land cover changes would benefit catchment ecological management. Landsat thematic mapper images in 1987, 1995, and 2007 were collected to obtain the historical normalized difference vegetation index and land cover data of the Beiluo River basin, one of the catchments in the Loess Plateau. The sediment load data of five subcatchments were collected in the corresponding periods. A set of location-weighted landscape contrast indices was used to analyze the effect of land cover changes on soil erosion processes, as specified by the following indices: slope gradient, flow path length, relative altitude, and relative distance. Results showed that vegetation cover (VC) notably increased from 41.12% to 63.43% in the basin from 1987 to 2007. The increased VC was mainly concentrated in the hilly-gully area from 18.40% in 1987 and 20.21% in 1995 to 41.65% in 2007. The mean annual sediment load modulus in the region over the same periods significantly decreased by 90%. All the indices for each subcatchment exhibited a decreasing trend. The change extent of the indices revealed a significantly positive correlation with that of sediment load modulus. Slope gradient and flow path length were the most important influential factors on soil erosion. Results implied that the improvement in land cover in the Beiluo River basin from 1987 to 2007 led to sediment entrapment in the sink area and changed the soil erosion processes, especially the slope gradient and flow length of the soil erosion source area. This study contributed to improving catchment ecological management and evaluating erosion control practices in the Loess Plateau. [ABSTRACT FROM AUTHOR]

A detailed investigation of the second harmonic generation in symmetrical and asymmetrical Gaussian potential quantum wells under the influence of applied electric field by using the compact-density-matrix approach and the finite difference method. The results show that the second-harmonic generation susceptibility obtained in two cases can reach the magnitude of 10 −4 m/V, which depend dramatically on the applied electric field and the structural parameters. Finally, the resonant peak and its corresponding to the resonant energy are also taken into account. [ABSTRACT FROM AUTHOR]