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This paper examines the ways in which three external governance mechanisms, namely market preferences, institutional investors, and debtholder monitoring, influence dividend payout decisions under a family-governance system. We find that family firms issue lower dividends when the dividend premium is high in the market. Institutional investors and family-controlled governance mechanisms interact to increase dividend payouts. Family firms under greater debtholder monitoring pay out more cash to shareholders. Our findings generate important policy implications.

The burr influences the surface quality and the performance of the part. Nowadays, vibration-assisted drilling (VAD) is used to decrease the exit burr size. However, further analysis of the VAD burr formation mechanism is required. A mathematical burr prediction model of low-frequency VAD is proposed for the aluminum 7075-T6 alloy cutting. This model includes material deformation mechanisms, multi-region thrust force, and VAD kinematic characteristics. In the material deformation process of VAD, the Johnson-Cook model and fracture model are considered. The results indicate that the experimental burr height is consistent with the model prediction values, and the deviation is less than 8%. The average burr height of VAD decreases by 49.5 %–52.6 % compared with conventional drilling (CD). The parameter analysis shows that the vibration amplitude had the highest sensitivity to the burr height. In the Multivariate regression analysis (MRA), the regression coefficient sum of vibration-related parameters’ absolute values (0.676) approximates the sum of other parameters’ absolute values (0.817).

Among transition metal phosphides, CoNiP was considered to be the most promising electrocatalyst for hydrogen evolution reaction (HER) to replace the precious metal platinum for its excellent catalytic performance and durability. In this work, an approach combining impregnation with calcination and phosphorization was used to prepare highly dispersed CoNiP nanoparticles on nitrogen-doped carbon nanotubes (NCNTs). The CoNiP/NCNTs catalysts exhibited the advantages of low overpotential and high durability. The content of sodium hypophosphite as phosphorization agent was a crucial factor to affect the performance of the catalysts. The optimized CoNiP/NCNTs with an appropriate content of sodium hypophosphite exhibited best performance with an onset-overpotential of 44 mV and a overpotential of 75 mV at a current density of 10 mA cm−2 in 0.5M H2SO4. After the chronopotentiometry measurement for 24h, the overpotential presented a decrease of only 6 mV, indicating its excellent durability.

The efficiency improvements of large area (244.34 cm2) crystalline silicon solar cells have been receiving significant attention, especially in high-efficiency multi-crystalline silicon (mc-Si) Passivated Emitter and Rear Contact (PERC) cells. The large area boron-doped mc-Si PERC cells were treated with hydrogenation for a different duration based on high-intensity infrared (HI-IR) LEDs of 940 nm. Compared to the boron-doped monocrystalline silicon (mono-Si) PERC cells, different trends of efficiency improvement were displayed after various hydrogenation duration. The results showed that the amplitude of the efficiency improvement was enhanced to the maximum around 8 min but then slowly decreased with the increasing hydrogenation duration. Moreover, we found that the iron-boron (Fe-B) pairs may occupy the dominant role in hindering the improvement of efficiency and the light-induced degradation (LID) after hydrogenation. The trend of efficiency improvement depended on the density of interstitial iron ions (Fe i + ) and the formation and dissociation of Fe-B pairs. Therefore, a longer duration of hydrogenation was required for mc-Si PERC cells than for mono-Si PERC cells to enhance the efficiency and suppress the degradation. Additionally, the duration of hydrogenation was significantly shortened to 1 min when the pre-LID was applied, then the appropriate extension of the hydrogenation duration was more conducive to the efficiency improvement of mc-Si PERC cells.

To investigate the correlation and predictive value of serum matrix metalloproteinase-9 (MMP-9) level with cognitive dysfunction and total imaging load in patients with cerebral small vessel disease (CSVD).A total of 80 patients with CSVD who were admitted to the First Affiliated Hospital of Xinxiang Medical University between April 2019 and April 2020 were enrolled. All subjects underwent T1-weighted imaging (T1WI), T2WI, fluid-attenuated inversion recovery (FLAIR), diffusion weighted imaging (DWI), serum sample collection, and assessment of cognitive function at a specific time-point after admission. According to the results of the neuropsychological test, subjects were divided into cognitive dysfunction group (n=40) and normal cognitive function group (n=40). The total imaging load was estimated according to the neuroimaging findings. Serum MMP-9 level was measured by an enzyme-linked immunosorbent assay (ELISA) kit. Beside, serum MMP-9 level and total imaging load were compared between the two groups.Serum levels of MMP-9 and plasma total homocysteine (tHcy) were negatively correlated with cognitive function (P0.05). Serum MMP-9 level was found as a significant factor for diagnosing cognitive impairment due to CSVD (area under the curve (AUC), 0.756; sensitivity and specificity were 97.5% and 75.0%, respectively). THcy level was also found as significant factor for diagnosing cognitive impairment due to CSVD (area under the curve (AUC), 0.727; sensitivity and specificity were 97.5% and 75.0%, respectively).Serum MMP-9 level and tHcy level were significantly correlated with cognitive function in patients with CSVD. Serum MMP-9 level has a specific correlation with the total imaging load in patients with CSVD. It plays an important role in diagnosing cognitive impairment in patients with CSVD.

Modal regression is a good alternative of the mean regression, because of its merits of both robustness and high inference efficiency. This paper is concerned with modal regression based statistical inference for semivarying coefficient models with longitudinal data, which include modal regression generalized estimating equations, modal regression empirical likelihood inference procedure for the parametric component and smooth- threshold modal regression generalized estimating equations for variable selection. These methods can incorporate the correlation structure of the longitudinal data and inherit the robustness and efficiency superiorities of the modal regression by choosing an appropriate data adaptive tuning parameter. Under mild conditions, the large sample theoretical properties are established. Simulation studies and real data analysis are also included to illustrate the finite sample performance.

To accommodate the changing needs of the developing brain, microglia must undergo substantial morphological, phenotypic, and functional reprogramming. Here, we examined whether cellular metabolism regulates microglial function during neurodevelopment. Microglial mitochondria bioenergetics correlated with and were functionally coupled to phagocytic activity in the developing brain. Transcriptional profiling of microglia with diverse metabolic profiles revealed an activation signature wherein the interleukin (IL)-33 signaling axis is associated with phagocytic activity. Genetic perturbation of IL-33 or its receptor ST2 led to microglial dystrophy, impaired synaptic function, and behavioral abnormalities. Conditional deletion of Il33 from astrocytes or Il1rl1, encoding ST2, in microglia increased susceptibility to seizures. Mechanistically, IL-33 promoted mitochondrial activity and phagocytosis in an AKT-dependent manner. Mitochondrial metabolism and AKT activity were temporally regulated in vivo. Thus, a microglia-astrocyte circuit mediated by the IL-33-ST2-AKT signaling axis supports microglial metabolic adaptation and phagocytic function during early development, with implications for neurodevelopmental and neuropsychiatric disorders.

Streaming data analysis has drawn much attention, where large amounts of data arrive in streams. Because limited memory can only store a small batch of data, fast analysis without access to the historical data is necessary. Quantile regression has been widely used in many fields because of its robustness and comprehensiveness. However, in the streaming data environment, it is challenging to implement quantile regression by the conventional methods, because they are all based on the assumption that the memory can fit all the data. To fix this issue, this paper proposes a novel online renewable quantile regression strategy, in which the resulting estimator is renewed with current data and summary statistics of historical data. Thus, it is computationally efficient, and not storage-intensive. What is more, the theoretical results also confirm that the proposed estimator is asymptotically equivalent with the oracle estimator calculated using the entire data together. Numerical experiments on both synthetic and real data verify the theoretical results and illustrate the good performance of the new method.

In Alzheimer's disease (AD), dementia severity correlates most strongly with decreased synapse density in the hippocampus and cerebral cortex. Although studies in rodents have established that hippocampal long-term potentiation (LTP) is inhibited by soluble oligomers of beta-amyloid (Aβ), the synaptic mechanisms remain unclear. Here, field excitatory postsynaptic potentials (fEPSP) recordings were made in the CA1 region of mouse hippocampal slices. The medium of APP-expressing CHO cells, which contain soluble forms of Aβ including small oligomers, inhibited LTP and facilitated long-term depression (LTD), thus making the LTP/LTD curve shift toward the right. This phenomenon could be mimicked by the non-selective glutamate transporter inhibitor, DL-TBOA. More specifically, the Aβ impaired LTP and facilitated LTD were occluded by the selective astrocytic glutamate transporter inhibitors, TFB-TBOA. In cultured astrocytes, the Aβ oligomers also decrease astrocytic glutamate transporters (EAAT1, EAAT2) expression. We conclude that soluble Aβ oligomers decrease the activation of astrocytic glutamate transporters, thereby impairing synaptic plasticity.

Statistical analysis of massive data is becoming more and more common. Distributed composite quantile regression (CQR) for massive data is proposed in this paper. Specifically, the global CQR loss function is approximated by a surrogate one on the first machine, which relates to the local data only through their gradients, then the estimator is obtained on the first machine by minimizing the surrogate loss. Because the gradients of local datasets can be efficiently communicated, the communication cost is significantly reduced. In order to reduce the computational burdens, the induced smoothing method is applied. Theoretically, the resulting estimator is proved to be statistically as efficient as the global CQR estimator. What is more, as a direct application, a smooth-threshold distributed CQR estimating equations for variable selection is proposed. The new methods inherit the robustness and efficiency advantages of CQR. The promising performances of the new methods are supported by extensive numerical examples and real data analysis.

As nickel-rich cathodes materials begin to attract immense attentions for its ultra-high capacity for Li-ion batteries (LIBs), their cycling stability remains insufficient for electric vehicles. Surface coating is regarded as an efficient approach in the enhancement of Ni-rich cathodes. Unfortunately, surface modification of cathode via a simple and effective way is still great challenges. Here we report a facile one-step chemical approach using nanoscale polycrystalline of solid electrolyte Li3.2Zr0.4Si0.6O3.6 (NP-LZSO) to build a conductive protective coating on Ni-rich cathode LiNi0.8Co0.15Mn0.05O2 (NCM). The NP-LZSO coating layer facilitates the transportation of Li-ions, significantly suppresses the undesired side reactions in cycling process, and effectively stabilizes the electrolyte-NCM interface. This approach remarkably improves the cycling stability with a capacity retention rate of 79.9% over 400 cycles at 0.2C. This effective strategy provides a new insight using nanoscale polycrystalline of solid electrolyte to modify surface of nickel-rich cathodes to improve its cyclic performance.

Modal regression is a good alternative of the mean regression and likelihood based methods, because of its robustness and high efficiency. A robust communication-efficient distributed modal regression for the distributed massive data is proposed in this paper. Specifically, the global modal regression objective function is approximated by a surrogate one at the first machine, which relates to the local datasets only through gradients. Then the resulting estimator can be obtained at the first machine and other machines only need to calculate the gradients, which can significantly reduce the communication cost. Under mild conditions, the asymptotical properties are established, which show that the proposed estimator is statistically as efficient as the global modal regression estimator. What is more, as a specific application, a penalized robust communication-efficient distributed modal regression variable selection procedure is developed. Simulation results and real data analysis are also included to validate our method.

Carbon fiber reinforced plastics (CFRP) /Titanium alloy (Ti) stacks are being extensively applied in aerospace area for superior mechanical properties. During drilling of CFRP/Ti stacks, irreparable thermal damage in CFRP at the stack interface can be easily induced by high interface temperature. This paper contributes to scientific understandings of cutting temperature characteristics, heat dissipation and resulting surface integrity in CFRP at the stack interface in both Ultrasonic Assisted Drilling (UAD) and Conventional Drilling (CD) of CFRP/Ti stacks. Results show that, similar to cutting temperature characteristics, a sudden drop of interface temperature occurs in UAD rather than a slight increase in CD. Compared with CD, the maximum interface temperature and duration of temperature beyond the glass transition temperature at stack interface in UAD are reduced by about 22.8% and 52.2% at n = 1000 rpm and f = 5 μm/rev respectively. With the aid of those findings, the relationships between temperature distribution in CFRP at the stack interface and drilling parameters have been discovered and temperature effects on CFRP hole exit damages have been elucidated. The findings of this paper can contribute to identifying the heat affected zone of CFRP and providing guidance for industrial practice to reduce the negative temperature effect in drilling of CFRP/Ti stacks.

The safety issues of lithium batteries caused by liquid organic electrolyte have been driving people to seek safer solid-like electrolytes. Herein, we report effort to employ Polyurethane acrylate (PUA) elastomer and Succinonitrile (SN)-based plastic crystal electrolyte (PCE) to fabricate a composite PCE (CPCE) by solution blending followed by rapid UV curing. During fabrication process, the phase separation between PUA and SN-based PCE can be suppressed by adding Tetrahydrofuran (THF). Consequently, the improved compatibility results in an improved mechanical strength in the CPCE and makes PUA impart the good stretching and resilient properties to the CPCE. The optimized CPCE presents a maximum stretching strain of 90.6% and can bear cyclic stretching-releasing test. Besides, the CPCE exhibits a high ionic conductivity of 0.91 × 10 −3 S cm −1 at 30 °C and a wide electrochemical stability window of 4.8 V. Thus, this stretchable CPCE could be used in flexible batteries for emerging applications such as wearable electronic devices and flexible sensors.

Since Li-ion batteries made of Li-rich layered materials might work at extreme environments, understanding the low temperature properties of Li-rich layered materials is of great importance. In this article, the low temperature properties and corresponding mechanism of Li-rich layered materials with a great amount of activated Li 2 MnO 3 are unraveled through a comparison of the low temperature characteristics of Li-rich layered materials with a small amount of activated Li 2 MnO 3 versus the former. Our findings indicate that in the electrode with a large amount of activated Li 2 MnO 3, the sluggish kinetics of the electrode reaction at low temperatures suppresses greatly the Mn 4+ /Mn 3+ reduction reaction, leading to much smaller initial discharge capacity and much better cyclic performance compared with situations at room temperature. Moreover, the increasingly suppressed Mn 4+ /Mn 3+ reduction reaction stop the discharge voltage fading, which might mitigate the layered-to-spinel phase transformation.

A high tap density for cathode active material is desirable because it is beneficial to the improvement of volumetric energy density of Li-ion battery. However, a high tap density for lithium rich layered cathode material was hardly achieved because of the low tap density of spherical precursors with a loose packing of the plate-shaped long rectangular primary particles prepared by the conventional NH3-bearing co-precipitation method in atmosphere of flowing nitrogen. In this article, irregular Li1.2Mn0.54Ni0.13Co0.13O2 particles with a high tap density were prepared using irregular precursors with a tight packing of the spherical primary particles synthesized by a NH3-free co-precipitation method in atmosphere of flowing air. The galvanostatic charge/discharge measurement indicates that the irregular Li1.2Mn0.54Ni0.13Co0.13O2 particles possess a high gravimetric capacity of 259 mAh g−1 and a volumetric capacity of 926 mAh cm−3. The superior electrochemical performance of as-prepared material can be attributed to that the irregular secondary particle have a large specific surface area and small pore volume detected by both nitrogen absorption method and mercury intrusion method and that the primary particle possesses more active planes exposure observed through HR-TEM images.

Incorporation of drug nanocrystal (DNC) into a particulate carrier to form the DNC delivery system was conducted in this study, where 10-hydroxycamptothecin (HCPT) was selected as the model drug and zein was the carrier. The supercritical anti-solvent (SAS) process or the built-in ultrasonic dialysis process (BUDP) was applied to prepare HCPT NC-loaded zein microspheres (HCPT NC-Zein MS) at first respectively, but the results showed that the products obtained were unsatisfactory in their particle microstructures. Fortunately, by combining the SAS process with BUDP, i.e. the co-precipitation of HCPT and zein prepared using the SAS process was dispersed into ethanol–water as the dialysis solution for BUDP, the results showed that desirable HCPT NC-Zein MS were obtained. The formulations were evaluated quantitatively by an overall desirability function (DF), and the optimized HCPT NC- Zein MS was prepared according to the range analysis results of DF. Under the optimized conditions, HCPT NC-Zein MS with a mean particle size=1.10±0.12 µm, drug loading=5.98% and encapsulation efficiency=95.68% were obtained. The further characterizations of SEM, FT-IR, XRD and DSC demonstrated that HCPT NC was successfully incorporated into the interior of zein microspheres. The effects of the process parameters and the formation mechanism of HCPT NC-Zein MS were discussed in detail. Furthermore, it is presented that HCPT NC-Zein MS sustained HCPT release rate successfully, where about 50% HCPT was fast released in the first 20 h, then the release trend followed zero order kinetics and reached 70% in 82 h.

Light injection and cooling conditions can induce some differences in the temperature-raising time of multi-crystalline silicon (mc-Si) solar cells. Through real-time tracking and monitoring of sample surface temperature, the temperature-raising steps for achieving the optimum efficiency improvement and degradation mitigation were optimized and modified. Then the corresponding hydrogenation treatments under a high-intensity infrared LEDs source were carried out based on improved steps. The results indicated that the optimal temperature-raising time should be manipulated at around 60 s and then followed by a 2-min hydrogenation treatment. Furthermore, the temperature-raising process should keep the temperature rising continuously without interruption or temperature drop. However, excessive thermal treatment time damaged the formation of defect precursors and extended the hydrogenation time. Moreover, the Fourier Transform Infrared spectrum curves illustrated that the peak intensity of the Si–H bonds treated at the 60-s temperature-raising time was more significant than that of other temperature-raising time treatments.

Vibration-assisted machining (VAM) is implemented in titanium alloy processing to solve some challenges, such as difficulty in chip breaking, large cutting forces, and high cutting temperatures. Based on the multi-region dynamic angles and the double-side wedge angle deformation mechanism, this study improves the vibration-assisted drilling (VAD) cutting forces and chip breaking model. The dynamic kinematics angles, the behavior of parameter influence, and the cutting strain effect of intermittent VAM are analyzed. VAD and conventional drilling (CD) experiments are carried out for model validation and mechanism analysis. The experiments show that the maximum deviation of the drilling forces simulation value and the experimental value is 9.13 %. Compared with the CD, the cutting force of the VAD is decreased by 10.1 %–46.2 %. The dynamic feed angle causes multiple cutting angles fluctuations, which affects cutting performance. The adjustment of the VAD cutting parameter value could reduce the chip length by 26.6 %–43.9 %. Material cutting strain presents multi-region characteristic, which influences the chip morphology. This study provides a reference for VAM parameter optimization.

Epileptic activity may be more prevalent in early stage Alzheimer’s disease (AD) than previously believed. Several studies report spontaneous seizures and interictal discharges in mouse models of AD undergoing age-related Aβ accumulation. The mechanism by which Aβ-induced neuronal excitability can trigger epileptiform activity remains unknown. Here, we systematically examined field excitatory postsynaptic potentials in stratum radiatum and population spikes in the adjacent stratum pyramidale of CA1 in wild-type mouse hippocampal slices. Soluble Aβ oligomers (oAβ) blocked hippocampal LTP and EPSP-spike (E-S) potentiation, and these effects were occluded by prior treatment with the glutamate uptake inhibitor TBOA. In accord, oAβ elevated glutamate levels in the hippocampal slice medium. Recording population spikes (PS) revealed that oAβ increased PS frequency and reduced LTP, and the latter effect was occluded by pretreatment with the GABAA antagonist picrotoxin. Whole-cell recordings showed that oAβ significantly increased spontaneous EPSC frequency. Decreasing neuronal activity by increasing GABA tone or partially blocking NMDAR activity prevented oAβ impairment of hippocampal LTP. Finally, treating slices with two antiepileptic drugs rescued the LTP inhibition induced by oAβ. We conclude that soluble Aβ oligomers at the low nanomolar levels present in AD brain increase neuronal excitability by disrupting glutamatergic/GABAergic balance, thereby impairing synaptic plasticity.

Zebrafish (Danio rerio) are rapidly emerging as an important model organism for aquatic neuropharmacology and toxicology research. The behavioral/phenotypic complexity of zebrafish allows for thorough dissection of complex human brain disorders and drug-evoked pathological states. As numerous zebrafish models become available with a wide spectrum of behavioral, genetic, and environmental methods to test novel drugs, here we discuss recent zebrafish phenomics methods to facilitate drug discovery, particularly in the field of biological psychiatry. Additionally, behavioral, neurological, and endocrine endpoints are becoming increasingly well-characterized in zebrafish, making them an inexpensive, robust and effective model for toxicology research and pharmacological screening. We also discuss zebrafish behavioral phenotypes, experimental considerations, pharmacological candidates and relevance of zebrafish neurophenomics to other 'omics' (e.g., genomic, proteomic) approaches. Finally, we critically evaluate the limitations of utilizing this model organism, and outline future strategies of research in the field of zebrafish phenomics.

Aims Circular RNA PRKCI (circPRKCI) and poly ADP-ribose polymerase 9 (PARP9) are related to the development of cancers. In this study, we aimed to explore the regulatory mechanisms between circPRKCI and PARP9 in EC progression and radioresistance. Materials and methods The levels of circPRKCI, PARP9 mRNA, and miR-186-5p were assessed by quantitative real time polymerase chain reaction (qRT-PCR). Western blot analysis was employed to examine the levels of several proteins. The viability, colony formation, cell cycle progression, and apoptosis of EC cells were determined with CCK-8, colony formation, or flow cytometry assays. The relationship between circPRKCI or PARP9 and miR-186-5p was verified with the dual-luciferase reporter and RIP assays. Key findings We observed that circPRKCI and PARP9 were upregulated while miR-186-5p was downregulated in EC tissues and cells. Furthermore, circPRKCI knockdown decreased tumor growth in vivo and constrained cell viability, colony formation, cell cycle progression, elevated cell radiosensitivity in EC cells in vitro. Importantly, circPRKCI modulated PARP9 expression through sponging miR-186-5p. Besides, PARP9 overexpression overturned circPRKCI silencing-mediated effects on the viability, colony formation, cell cycle progression, and radiosensitivity of EC cells. Significance CircPRKCI regulated cell malignancy and radioresistance through modulating the miR-186-5p /PARP9 axis in EC, which provided a might target for EC treatment.

Perovskite Solar Cells (PSCs) have drawn tremendous attentions from scientific community due to their advantages of high efficiency and low-cost. However, the mechanism of photoelectron generation is unclear because the light field distribution is difficult to be quantitively characterized by conventional methods. The Optical Transfer Matrix Method (OTMM) has been applied in organic devices based on p-n structures. We have applied different materials as back electrode to examine the light propagation inside of planar p-i-n solar cells with regular structure (Glass/ITO/SnOx/CH3NH3PbI3/Spiro-OMeTAD/Back electrode). The simulations were performed by using OTMM to carry out the optical field modeling of simulated solar cells in visible-near infrared (NIR) range. Among the simulation models, it has been found that perovskite solar cells based on sliver electrode has highest light intensity oscillation and faster charge generation rate. But sliver electrode has lower stability because the iodine can diffuse to the interface and form AgI with the assist of NIR-induced thermal effect. By contrast, the independent graphene electrode has disadvantages of interlayer conductivity and transparency. Based on the simulation result, we recommend that the graphene can be applied as a buffer layer between perovskite and sliver electrode instead of being an independent electrode.

As the most common cause of progressive cognitive decline in humans, Alzheimer’s disease (AD) has been intensively studied, but the mechanisms underlying its profound synaptic dysfunction remain unclear. Here we confirm that exposing wild-type mice to an enriched environment (EE) facilitates signaling in the hippocampus that promotes long-term potentiation (LTP). Exposing the hippocampus of mice kept in standard housing to soluble Aβ oligomers impairs LTP, but EE can fully prevent this. Mechanistically, the key molecular features of the EE benefit are an upregulation of miRNA-132 and an inhibition of histone deacetylase (HDAC) signaling. Specifically, soluble Aβ oligomers decreased miR-132 expression and increased HDAC3 levels in cultured primary neurons. Further, we provide evidence that HDAC3 is a direct target of miR-132. Overexpressing miR-132 or injecting an HDAC3 inhibitor into mice in standard housing mimics the benefits of EE in enhancing hippocampal LTP and preventing hippocampal impairment by Aβ oligomers in vivo. We conclude that EE enhances hippocampal synaptic plasticity by upregulating miRNA-132 and reducing HDAC3 signaling in a way that counteracts the synaptotoxicity of human Aβ oligomers. Our findings provide a rationale for prolonged exposure to cognitive novelty and/or epigenetic modulation to lessen the progressive effects of Aβ accumulation during human brain aging.

In orthopedics and surgery, bone drilling is an important operation. Increasing demands call for bone drilling force prediction and minimization. Vibration-assisted drilling (VAD) provides an opportunity to reduce the force. In the study, the information feedback self-adaptive harmony search (IFSHS) algorithm is presented for the thrust force minimization in bovine cortical bone VAD. The IFSHS improves the drilling parameters which leads to the optimal cutting state. The dynamic searching parameters, optimization parameters evaluation, and evaluation information feedback are applied to search the optimal solution. This force model was developed and employed with IFSHS. The VAD drilling experiments and parameters analysis are carried out. Experimental results have shown that the VAD has the potential to reduce the thrust force. Compared with conventional drilling (CD), the thrust force decreased by 18.4%–33.2% under suitable VAD parameters. Compared with the results of the original VAD parameters, the optimized thrust force decreased by 20.19%.

Considering the high harmfulness of NO2 to the environment and human healthy, it is pressing to develop NO2 sensors with high sensitivity and selectivity. In this work, we successfully fabricated a novel hierarchical SnO2–Sn3O4 n–n heterostructure through the solvothermal method and subsequent annealing. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FESEM), and high-resolution transmission electron microscopy (HRTEM) characterization of the material confirmed the hierarchical microsphere structure and the formation of SnO2–Sn3O4 n–n heterojunction. The gas sensing experiment demonstrated that the sample annealed at 600 °C exhibited excellent NO2 sensing performances at 150 °C. Its sensitivities to 5 and 10 ppm NO2 were as high as 48 and 43.6 ppm−1 respectively, and its limit of detection was lower than 20 ppb. Additionally, it possessed excellent selectivity to NO2 as well as good repeatability and stability. With further exploration of the sensing mechanism of hierarchical SnO2–Sn3O4 n–n heterostructure, we proposed that the unique microstructure with a large specific surface area and the formation of n–n-type heterojunctions contribute to the excellent NO2 sensing performance.

A porous carbon electrode incorporating considerations both heteroatom doping and pore structure design with: combination of melamine and PEO–PPO–PEO (polyethylene oxide–polypropylene oxide–polyethylene oxide) micelles for the nitrogen-doping and optimization the micron-duct formation; integration of CO2-etching into the carbonization process for the formation of abundant micropores. The structure of these nitrogen-doped carbon xerogels (NCXs) are indeed comprised of a multi-scaled pores having nano-porous carbon in a network of micron-size percolated hollow-channels. The resulted material has an ultrahigh surface area of 4279 m2 g−1 when used as electrode for supercapacitor, which deliver a high specific capacitance of 271 F g−1 with excellent cycle stability and good rate capability.

In this work, α-MoO 3 nanoparticles are grown on the surface of nitrogen doped carbon nanotubes (N-CNTs) via a facile electrodeposition method. The morphology of as-prepared nanocomposite shows that the interconnected α-MoO 3 nanoparticles are homogeneously distributed on the surface of N-CNTs. When investigated as a cathode material for lithium ion batteries, the nanocomposite reveals a high reversible discharge capacity of 250 mA h g −1 at a current density of 30 mA g −1 , simultaneously with good cycling performance and excellent rate capability compared with pristine MoO 3 powder. Kinetics of this process is investigated by electrochemical impedance spectroscopy to understand the difference in electrochemical performance and the interface properties between the α-MoO 3 /N-CNTs nanocomposite and pristine MoO 3 powder electrode. The correlation between the unique structural features of α-MoO 3 /N-CNTs nanocomposite and its excellent electrochemical performance is also discussed. The excellent performance makes the as-prepared α-MoO 3 /N-CNTs nanocomposite a promising cathode material for high-performance lithium ion batteries.

The performance of lithium sulfur (Li/S) battery was greatly improved by the employment of nitrogen doped carbon nanotubes (N-CNTs) based cathode. By manipulating its structure thereby creating more defects, N-CNTs presents better dispersion of sulfur particles on N-CNTs and higher electrical conductivity compared with their non-doped counterpart, which explain the reason why N-CNTs/S composite shows improved performance. The specific discharge capacity was maintained at 625 mAh g−1 and 513 mAh g−1 after 100 cycles at 0.2 C and 0.5 C, respectively, which was about 2 times as that of CNTs. This method is proved to be a promising way to develop cathode materials for lithium sulfur batteries.

Using 205 Taiwanese firms spanning five years, this research examines how corporate governance factors specific to emerging economies determine the extent of diversification and moderate its performance. The analyses reveal that controlling family ownership is significantly associated with a greater extent of diversification, which impairs firm value. Conversely, domestic bank ownership significantly decreases diversification, which in turn increases diversification performance. These findings present the evidence of controlling family entrenchment through diversification and the significant role domestic banks play in the principal–principal corporate governance framework.

We examine the effect of a country's governance environment on its propensity to trade. Using an updated framework of governance environment, we classify countries based on the dominant mode of governance into three types: (1) rule-based (strong public rule of law), (2) relation-based (weak rule of law and strong informal network based on private relations), and (3) family-based (absence of both public rules and private network). We then examine how different governance types affect trade patterns among 44 countries representing 89% of world trade. We find that overall, rule-based countries trade more than relation-based or family-based countries. A large positive effect on trade flows exists between two highly rule-based countries and between two relation-based countries. Any trade relationship involving a family-based country negatively affects trade flows, even between two family-based countries. Our study contributes to the trade literature by examining the effects of different types of governance environment on trade flows and more successfully explaining why some countries still trade almost nothing even after scholars and policy makers have convincingly proven that freer trade leads to higher welfare for a country.

Assessing the overall quality of Chinese financial data is important to both academic researchers and regulators. Using data from the industrial census of China, we examine the institutional pattern of the manipulation of reported profit statistics by manufacturing firms. This manipulation of profits is called “earnings management.” We find that earnings management is more pervasive in China than in mature market economies such as the U.S., and that Chinese firms appear to follow a “keep silent, make money” strategy by managing their reported earnings to zero. Specifically, we find that increased earnings management is associated with state-owned firms, firms reporting to higher levels of government, and firms in more marketized regions.

Summary Previous studies have primarily focused on the relative success of collectively owned enterprises (COEs) in China during the early years of reform, but they have ignored the agency problems inherent in this type of organizational form that may be an obstacle to further improving performance in a changing environment. Drawing on agency theory and the privatization literature, we argue that the transformed COEs in the ongoing organizational transformation process may achieve better performance by reducing agency costs. We examine a sample of COEs in Chinese manufacturing industries and track their ownership statuses from 2000 to 2005. Our findings reveal that the transformed firms achieved better performance than the traditional, untransformed COEs by mitigating agency problems.

An increasing body of evidence suggests that soluble assemblies of amyloid beta-protein (Abeta) play an important role in the initiation of Alzheimer disease (AD). In vitro studies have found that synthetic Abeta can form soluble aggregates through self-assembly, but this process requires Abeta concentrations 100- to 1000-fold greater than physiological levels. Tissue transglutaminase (TGase) has been implicated in neurodegeneration and can cross-link Abeta. Here we show that TGase induces rapid aggregation of Abeta within 0.5-30 min, which was not observed with chemical cross-linkers. Both Abeta40 and Abeta42 are good substrates for TGase but show different aggregation patterns. Guinea pig and human TGase induced similar Abeta aggregation patterns, and oligomerization was observed with Abeta40 concentrations as low as 50 nm. The formed Abeta40 species range from 5 to 6 nm spheres to curvilinear structures of the same width, but up to 100 nm in length, that resemble the previously described self-assembled Abeta protofibrils. TGase-induced Abeta40 assemblies are resistant to a 1-h incubation with either neprilysin or insulin degrading enzyme, whereas the monomer is rapidly degraded by both proteases. In support of these species being pathological, TGase-induced Abeta40 assemblies (100 nm) inhibited long term potentiation recorded in the CA1 region of mouse hippocampus slices. Our data suggest that TGase can contribute to AD by initiating Abeta oligomerization and aggregation at physiological levels, by reducing the clearance of Abeta due to the generation of protease-resistant Abeta species, and by forming Abeta assemblies that inhibit processes involved in memory and learning. Our data suggest that TGase might constitute a specific therapeutic target for slowing or blocking the progression of AD.

Antagonists at presynaptic muscarinic autoreceptors increase endogenous acetylcholine (ACh) release and enhance cognition but little is known regarding their actions on plasticity at glutamatergic synapses. Here the mechanisms of the persistent enhancement of hippocampal excitatory transmission induced by the M2/M4 muscarinic ACh receptor antagonist methoctramine were investigated in vivo . The persistent facilitatory effect of i.c.v. methoctramine in the CA1 region of urethane-anesthetized rats was mimicked by gallamine, an M2 receptor antagonist, supporting a role for this receptor subtype. Neither the N -methyl- d -aspartate (NMDA) receptor antagonists d -(−)-2-amino phosphonopentanoic acid ( d -AP5) and memantine, nor the metabotropic glutamate receptor subtype 1a antagonist (S)-(+)-α-amino-4-carboxy-2-methylbenzeneacetic acid (LY367385) significantly affected the methoctramine-induced persistent synaptic enhancement, indicating a lack of requirement for these glutamate receptors. The selective kinase inhibitors Rp-adenosine-3′, 5′-cyclic monophosphorothioate (Rp-cAMPS) and the myrostylated pseudosubstrate peptide, Myr-Ser-Ile-Tyr-Arg-Arg-Gly-Ala-Arg-Arg-Trp-Arg-Lys-Leu-OH (ZIP), were used to investigate the roles of protein kinase A (PKA) and the atypical protein kinase C, protein kinase Mζ (PKMζ), respectively. Remarkably, pretreatment with either agent prevented the induction of the persistent synaptic enhancement by methoctramine and post-methoctramine treatment with Rp-cAMPS transiently reversed the enhancement. These findings are strong evidence that antagonism of M2 muscarinic ACh receptors in vivo induces an NMDA receptor-independent persistent synaptic enhancement that requires activation of both PKA and PKMζ.

Summary It is commonly accepted that state-owned enterprises (SOEs) are inefficient and that non-state firms drive the phenomenal growth in China. However, why SOEs are not dying out and how the non-state firms thrive in a poor institutional environment remain unanswered. We apply the institutional and principal-agent perspectives to explain how firms with different ownerships deploy their resources and formulate strategies to achieve their goals. Using China’s industrial census data, we find that SOEs tend to adopt strategies conducive to fulfilling administrative tasks and empire-building, whereas the non-state firms tend to be more profitable in the market. Policy and strategic implications are discussed.

Traditionally, the Chinese government used an “iron fist” to control the economy and firms under central planning. However, the economic reforms since 1978 have substantially changed the institutional landscape. After more than two decades of dramatic economic transition, the economy is now neither planned nor market-based. Drawing from institutional theory, we examine the relationship between the government and firms and propose a number of hypotheses regarding how this relationship affects firm performance in China. We then test our hypotheses based on so far the largest and most authoritative industrial census data ever available to organizational research, which represents more than 90% of China's total industrial output. We find that government control at different levels, type of ownership, degree of privatization, and the government–firm bargaining relationship significantly affect firm performance. Our examination into the lishu relationship sheds light on an important heretofore unknown issue in firm performance during China's transitional economy. Implications for research, policy, and strategy are discussed.