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Herein, we systematically investigated the reaction mechanism of n-pentane cracking on the Ag/ZSM-5 bifunctional catalyst featuring both dehydrogenation and cracking capabilities. Specifically, overall cracking network of n-pentane was comprehensively constructed to show the roles of metal dehydrogenation sites and acid sites respectively, in which metal Ag could substitute the H of the Brønsted acid site to form the Al-O-Ag linkage with enhanced adsorption and activation of n-pentane, while Brønsted acid site with weak acid strength relay to promote cracking reaction. Thanks to this synergy of the two active sites, the apparent activation energy of n-pentane cracking to light olefins was decreased from 82.77 KJ/mol to 68.26 KJ/mol and the proportion of specific path (C5H12→H2+C5H10) in n-pentane monomolecular cracking reaction increased from 14.62% to 69.24%. In addition, 0.57Ag/ZSM-5 catalyst exhibited the conversion of n-pentane up to 67.55wt%, which improved the performance of the parent ZSM-5 by 13.42wt%.

To summarize and analyze the clinical efficacy and safety of neuroendoscopic surgery (NES) in the treatment of patients for severe thalamic hemorrhage with ventricle encroachment (THVE). Eighty-three patients with severe THVE were treated in the Neurosurgery Department of Anqing Hospital Affiliated to Anhui Medical University from July 2019 to August 2021. Our study was approved by the ethics committee. The patients were randomly divided into NES group and extraventricular drainage (EVD) group. The hospital stay, Glasgow coma scale (GCS) scores on the 1st and 14th days postoperatively, the incidence of intracranial infections, and the clearance of postoperative hematomas were compared and analyzed between the two groups. The patients had follow-up evaluations 6 months postoperatively. The prognosis was evaluated based on the activity of daily living (ADL) score. A head CT or MRI was obtained to determine whether there was hydrocephalus, cerebral infarction, or other related complications. Eighty-three patients were randomly divided into 41 cases of NES group and 42 cases of EVD group. The length of postoperative hospital stay was 17.42 ± 1.53 days, the GCS scores were 6.56 ± 0.21, and 10.83 ± 0.36 on days 1 and 14, respectively; intracranial infections occurred in 3 patients (7.31%) and the hematoma clearance rate was 83.6 ± 5.18% in the NES group, all of which were significantly better than the EVD group (P 0.05). After 6 months of follow-up, 28 patients (68.29%) had a good prognosis, 5 patients (12.19%) died, and 4 patients (9.75%) had hydrocephalus in the NES group. In the EVD group, the prognosis was good in 15 patients (35.71%), 12 patients (28.57%) died, and 17 patients (40.47%) had hydrocephalus. The prognosis, mortality rate, and incidence of hydrocephalus in the NES group were significantly better than the EVD group (P 0.05). Compared to traditional EVD, NES for severe THVE had a higher hematoma clearance rate, and fewer intracranial infections and patients with hydrocephalus, which together improve the clinical prognosis and is thus recommended for clinical use.

Innate immunity plays critical antiviral roles. The highly virulent avian influenza viruses (AIVs) H5N1, H7N9, and H5N6 can better escape host innate immune responses than the less virulent seasonal H1N1 virus. Here, we report a mechanism by which transcriptional readthrough (TRT)-mediated suppression of innate immunity occurs post AIV infection. By using cell lines, mouse lungs, and patient PBMCs, we showed that genes on the complementary strand (“trans” genes) influenced by TRT were involved in the disruption of host antiviral responses during AIV infection. The trans-TRT enhanced viral lethality, and TRT abolishment increased cell viability and STAT1/2 expression. The viral NS1 protein directly bound to SSU72, and degradation of SSU72 induced TRT. SSU72 overexpression reduced TRT and alleviated mouse lung injury. Our results suggest that AIVs infection induce TRT by reducing SSU72 expression, thereby impairing host immune responses, a molecular mechanism acting through the NS1-SSU72-trans-TRT-STAT1/2 axis. Thus, restoration of SSU72 expression might be a potential strategy for preventing AIV pandemics.

Bionic perception, especially temperature-aware, is one of the important issues in soft robots research. This paper presents a method to implant temperature sensor network into soft robot finger by using optical fiber gratings. For avoiding strain disturbance, a dedicated metal tube is designed to package and protect the optical fiber gratings. For implanting the sensors firmly, a solution using two kinds of adhesive is proposed. The prototype is calibrated in high precision temperature bath and then measured under different temperatures and different bending conditions, respectively. The experimental results are compared with electronic temperature sensor (PT100 thermal resistance), which verifies the accuracy and repeatability of the design. With the dedicated coating and adhesive solution, the proposed temperature sensor network is suitable for implanting into soft robots for the temperature-aware ability.

Flexible pressure sensors possess superior conformal ability, great flexibility, and strong biocompatibility than conventional silicon-based sensors, thereby widely used in electronic skin, wearable devices, and robotic tactile sensing, among other fields. However, flexible pressure sensors are still limited by many challenges related to extended linearity and high sensitivity. In this paper, MXene with a loose layered structure was employed to fabricate high-performance flexible piezoresistive sensors comprising polydimethylsiloxane (PDMS) film with cylindrical microstructure, multilayer Ti3C2T x -MXene film, and interdigital electrodes. A cylindrical microstructured silicon wafer was designed and processed by deep silicon etching process, and PDMS flexible substrate was obtained by two inversions as the pressure sensing layer. The resulting flexible pressure sensor exhibited excellent performance in terms of excellent sensitivity up to 519 kPa−1 in the large detection range of 0–8 kPa coupled with great linearity, a response time of 62.7 ms, and a recovery time of 62.8 ms. The high sensitivity was associated with the compression of the interlayer spacing of multilayer MXene nanosheets. In addition, a single flexible pressure sensor and integrated array were utilized to detect the human physical signals and quantitative measurements of pressure distributions. Overall, these findings provided experimental verification for the design and manufacturing of highly sensitive and linear flexible pressure sensors.

We propose a general learning based framework for solving nonsmooth and nonconvex image reconstruction problems. We model the regularization function as the composition of the $l_{2,1}$ norm and a smooth but nonconvex feature mapping parametrized as a deep convolutional neural network. We develop a provably convergent descent-type algorithm to solve the nonsmooth nonconvex minimization problem by leveraging the Nesterov's smoothing technique and the idea of residual learning, and learn the network parameters such that the outputs of the algorithm match the references in training data. Our method is versatile as one can employ various modern network structures into the regularization, and the resulting network inherits the guaranteed convergence of the algorithm. We also show that the proposed network is parameter-efficient and its performance compares favorably to the state-of-the-art methods in a variety of image reconstruction problems in practice.

Aircraft stealth by avoiding radar detection relies on shape and materials, but these are ineffective in attenuating electromagnetic (EM) waves in the ultrahigh frequency (UHF) band. This article investigates broadband EM wave attenuation in dielectric-barrier discharge (DBD) plasmas. We used a simplified collisional-radiative model to determine the electron density distribution using 2-D emission spectra and found that the gas pressure has a great effect on electron density. An empirical relationship between the gas pressure and electron density is given. We introduce a parameter optimizing method for multilayer plasmas that combines the attenuation characteristics of EM waves in plasma. We also establish an ideal multilayer plasma model to calculate the EM wave attenuation in the UHF band. The results show that multilayer plasmas can effectively enlarge the effective attenuating frequency range of EM waves and also attenuate UHF EM waves. On the basis of the calculation results, we propose a single-layer plasma generator. A large-area and homogenous plasma under medium-to-high gas pressure can also be created by discharge with argon or a mixture of argon and helium.

Deep neural network architectures based on unrolling optimization algorithms have been widely adopted in deep-learning based image reconstruction applications in recent years. However, these architectures only mimic the iterative schemes of the corresponding algorithms, but lack rigorous convergence guarantee; and the learned network layers are difficult to interpret. These issues have hindered their applications in clinical use. In this paper, we develop an efficient Learned Descent Algorithm with a Line Search strategy (LDA-LS) and apply it to the nonconvex nonsmooth optimization problem of low-dose CT (LDCT) reconstruction. We show that LDA-LS yields a highly interpretable neural network architecture, where the regularization parameterized as multilayer perception is explicitly integrated into the iterative scheme and learned during the training process. We demonstrate that LDA-LS retains convergence guarantee as classical optimization algorithms, while achieving improved efficiency and accuracy in LDCT image reconstruction problems.

A novel direct torque control (DTC) method with copper loss minimization is proposed for the brushless dc motor (BLDCM) in electric vehicle (EV) application. In order to realize high efficiency and high torque control precision at the same time, a special stator flux linkage trajectory is designed based on pseudo-dq transformation for maximum torque per ampere (MTPA) control of BLDCM. The three-phase conduction voltage vectors switch table is used to realize the flux linkage tracking control for high dynamic performance of torque control. The torque ripple caused by the non-ideality of the back EMF and the commutation in traditional two-phase conduction voltage vector based DTC method can be eliminated, which improves the torque control precision. The validity and effectiveness of the proposed DTC scheme are verified through experimental results.

We present an algorithm for multi-scale tumor (chimeric cell) detection in high resolution slide scans. The broad range of tumor sizes in our dataset pose a challenge for current Convolutional Neural Networks (CNN) which often fail when image features are very small (8 pixels). Our approach modifies the effective receptive field at different layers in a CNN so that objects with a broad range of varying scales can be detected in a single forward pass. We define rules for computing adaptive prior anchor boxes which we show are solvable under the equal proportion interval principle. Two mechanisms in our CNN architecture alleviate the effects of non-discriminative features prevalent in our data - a foveal detection algorithm that incorporates a cascade residual-inception module and a deconvolution module with additional context information. When integrated into a Single Shot MultiBox Detector (SSD), these additions permit more accurate detection of small-scale objects. The results permit efficient real-time analysis of medical images in pathology and related biomedical research fields.

Drug repurposing is a quick and economical strategy for developing new therapies with approved drugs. H5N1 is a highly pathogenic avian influenza virus subtype that can cause severe acute lung injury (ALI) and a high mortality rate due to limited treatments. The use of RNA interference (RNAi) is a reliable approach to identify essential genes in diseases. In most genomewide RNAi screenings, virus replication is the readout of interference. Since H5N1 virus infection could induce significant cell death and the percentage of cell death is associated with virus lethality, we designed a genomewide RNAi screening method to identify repurposable drugs against H5N1 virus with cell death as the readout. We discovered that the neurological drug ifenprodil and the anticancer drug flavopiridol could effectively ameliorate murine ALI after influenza A H5N1 virus infection, suggesting that they might be novel remedies for H5N1 virus-induced ALI in addition to the traditional indications., Due to the limitations of effective treatments, avian influenza A H5N1 virus is the most lethal influenza virus strain that causes severe acute lung injury (ALI). To develop effective drugs ameliorating H5N1-induced ALI, we explore an RNA interference (RNAi) screening method to monitor changes in cell death induced by H5N1 infection. We performed RNAi screening on 19,424 genes in A549 lung epithelial cells and examined cell death induced by H5N1 infection. These screens identified 1,137 host genes for which knockdown altered cell viability by over 20%. DrugBank searches of these 1,137 host genes identified 146 validated druggable target genes with 372 drug candidates. We obtained 104 commercially available drugs with 65 validated target genes and examined their improvement of cell viability following H5N1 infection. We identified 28 drugs that could significantly recover cell viability following H5N1 infection and tested 10 in an H5N1-induced-ALI mouse model. The neurological drug ifenprodil and the anticancer drug flavopiridol markedly decreased leukocyte infiltration and lung injury scores in infected mouse lungs, significantly ameliorated edema in infected mouse lung tissues, and significantly improved the survival of H5N1-infected mice. Ifenprodil is an antagonist of the N-methyl-d-aspartate (NMDA) receptor, which is linked to inflammation and lung injury. Flavopiridol is an inhibitor of cyclin-dependent kinase 4 (CDK4), which is linked to leukocyte migration and lung injury. These results suggest that ifenprodil and flavopiridol represent novel remedies against potential H5N1 epidemics in addition to their proven indications. Furthermore, our strategy for identifying repurposable drugs could be a general approach for other diseases. IMPORTANCE Drug repurposing is a quick and economical strategy for developing new therapies with approved drugs. H5N1 is a highly pathogenic avian influenza virus subtype that can cause severe acute lung injury (ALI) and a high mortality rate due to limited treatments. The use of RNA interference (RNAi) is a reliable approach to identify essential genes in diseases. In most genomewide RNAi screenings, virus replication is the readout of interference. Since H5N1 virus infection could induce significant cell death and the percentage of cell death is associated with virus lethality, we designed a genomewide RNAi screening method to identify repurposable drugs against H5N1 virus with cell death as the readout. We discovered that the neurological drug ifenprodil and the anticancer drug flavopiridol could effectively ameliorate murine ALI after influenza A H5N1 virus infection, suggesting that they might be novel remedies for H5N1 virus-induced ALI in addition to the traditional indications.

Low-temperature thermochronology is used widely in the Tibet plateau uplift. Some researches, however, have defined the time of rapid denudation as simply rock uplift and have neglected the fact that the rock denudation recorded by fission track (FT) data was controlled by both surface incision and rock uplift. The incision of the Yarlung Zangbo River had a significant influence on uplift history inversion in Southern Tibet. This paper simulated the bedrock denudation and river incision histories using apatite fission track (AFT) data sampled from the Gangdese conglomerate belt, which is located in the middle of Southern Tibet, and analyzed the geological meaning of the AFT age of each sample. The results showed the following: (1) In the early Miocene (22–16 Ma), both the value of the denudation rate and the incision rate were high (0.56 mm/yr and 0.24 mm/yr). (2) In the middle-late Miocene, the incision rate (0.12 mm/yr) was similar to the denudation rate (0.09–0.11 mm/yr). (3) The historical model between river incision and bedrock denudation revealed a significant difference in the denudation rate during the period ca. 8–6 Ma. Combining these data with previously published thermochronological ages and synthesizing these ages with regional geological, we arrived at the following conclusions: (1) In the early Miocene, the denudation event probably was caused by a combined result of Indian plate rollback and the incision of the Yarlung Zangbo River. (2) In the middle-late Miocene, the denudation rate was consistent with the incision rate, which suggested that the denudation episode was caused by climate change associated with Asian monsoon intensification. (3) After 8 Ma, the stable and slow incision rate indicated that regional drastic uplift had ceased. The paleo-elevation of the research area had approached, and even exceeded, the present-day elevation in the late Miocene.

We report the first imported case of Rift Valley fever (RVF) in China. The patient returned from Angola, a non-epidemic country, with an infection of a new reassortant from different lineages of Rift Valley fever viruses (RVFVs). The patient developed multiorgan dysfunction and gradually recovered with continuous renal replacement therapy and a short regimen of methylprednisolone treatment. The disordered cytokines and chemokines in the plasma of the patient revealed hypercytokinemia, but the levels of protective cytokines were low upon admission and fluctuated as the disease improved. Whole-genome sequencing and phylogenetic analysis revealed that the imported strain was a reassortant comprising the L and M genes from lineage E and the S gene from lineage A. This case highlights that RVFV had undergone genetic reassortment, which could potentially alter its biological properties, cause large outbreaks and pose a serious threat to global public health as well as the livestock breeding industry.

Prediction of electron density is crucial to numerically evaluate the attenuation of electromagnetic waves in plasmas and to optimize the parameters. In this paper, a simple collisional-radiative model (CRM) to determine the electron density of Ar dielectric barrier discharge (DBD) plasmas for pressures ranging from 0.2 to 1 atm is introduced, and then, the attenuation of electromagnetic waves is analyzed. First, the radial average electron density of Ar DBD plasma is estimated by combining the measured current and a 1-D self-consist fluid numeric model. Second, based on a simple CRM, an optical emission spectroscopy method is used to determine the radial electron density distribution. Finally, according to the radial electron density distribution, the attenuation of electromagnetic waves is calculated at a frequency range from 10 MHz to 10 GHz. The result indicates that the electromagnetic waves with a relatively low frequency can be effectively attenuated by the plasma and the edge distribution of the plasma clearly affects the attenuation.

Background: Due to the limits of effective treatments, avian influenza A H5N1 virus is the most lethal influenza virus strain that causes severe acute lung injury (ALI). To develop effective drugs ameliorating H5N1-induced ALI, we explore an RNA interference (RNAi) screening method to monitor changes in cell death induced by H5N1 infection. According to the estimation of the Bernard Munos, a drug-development advocacy organization in Washington DC, "the proportion of drugs that in theory could be repositioned is probably approximately 75%." Methods: We screened 19,424 RNAi in A549 lung epithelial cells and examined cell death induced by H5N1 infection. These screenings identified 1137 host genes for which knockdown altered cell viability by over 20%. DrugBank searches of these 1137 host genes identified 146 validated druggable target genes with 372 drug candidates. We obtained 104 commercially available drugs with 65 validated target genes and examined their improvements in cell viability following H5N1 infection. We identified 28 drugs that could significantly recover cell viability following H5N1 infection and tested 10 in an H5N1-induced ALI mouse model. Findings: The neurological drug ifenprodil and the anticancer drug flavopiridol markedly decreased infiltrated leukocytes and lung injury scores in infected mouse lungs and significantly ameliorated lung edema in infected mouse lung tissue. Interpretation: Ifenprodil is an antagonist of the N-methyl-D-aspartate (NMDA) receptor, which is linked to inflammation and lung injury. Flavopiridol is an inhibitor of CDK4, which is linked to leukocyte migration and lung injury. These results suggest that ifenprodil and flavopiridol are novel remedies against potential H5N1 epidemics in addition to their proven indications. Furthermore, our strategy for identifying repurposable drugs could serve as a general approach for other diseases. Funding Statement: This work was supported by the National Natural Science Foundation of China (81788101, 81490531), the Ministry of Science and Technology of China (2015CB553406) and the CAMS Innovation Fund for Medical Sciences (2017-I2M-1-009). Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: Animal experiments in this work were approved by the Ethics Committee of the Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences (ACUC-A02-2017-014).

In order to summarize the relationship between reasonably well pattern and artificial fracture in Fuyu reservoir which using the vertical well development, we determined the fracture network scale of overlay channel and a single channel sand body on the basis of the fracture network fracturing test and the downhole microseismic fracture monitoring data and annulus testing data. The reasonable fracture network sizes of different sand bodies were obtained by establishing a typical well fracture-matrix model and applying numerical simulation of the production of 16 different fracture networks in 5 years. Under the premise of established reasonable scale of the fracture network, it provides reference for the reasonably well pattern in the new area with similar reserves in geological conditions by the comparing of the 5-year oil production in 6 different well spacing.

Pressure transmission inside a large-volume cubic press was examined using finite-element (FE) simulations. Calculations were carried out for the pyrophyllite P-transmitting mediums (32.5 × 32.5 × ...

The temperature field in a high-pressure synthetic cavity for diamond production is optimized by adjusting the cavity assembly. This paper aims to propose design rules for high-pressure cavity assembly and apply finite element simulation for analysis. Three assemblies, namely, conventional, D1, and D2, are presented and compared. The temperature field of each assembly is visualized via the finite element method. High-pressure experiments are then performed in a diamond synthesis factory. Compared with conventional assembly, D1 and D2 assemblies established on the basis of the proposed design rules can improve the conditions for diamond synthesis.

This paper presents a systematic derivation of a small signal model of current-fed half bridge isolated dc/dc converter for the hybrid electric vehicle based on the lithium battery and fuel cell. The reflected output voltage across the power semiconductor devices can naturally be clamped at V°/n by a secondary-modulation strategy without any additional circuit, which can reduce footprints and cost. Moreover, the soft switch of all can be achieved resulting in low switching losses and higher efficiency due to ZCS/ZVS. In order to maintain the constant bus voltage and the balanced two-way inductor current, a small signal model using state-space averaging technique is deduced and the dual closed loop controller is designed in detail. The co-simulation of PSIM and MATLAB/SIMULINK is used to verify the effectiveness of the controller when the load step-changes in case of the different input voltage.

The temperature-field in diamond synthesis cell was simulated by a finite element method. A three-dimensional model of the China-type cubic press with large deformation of the synthesis cell was established successfully, which has been verified by situ measurements of synthesis cell. In addition, the distributions of temperature and its gradient in the synthesis sample were described. We found there is a large temperature drop in the synthesis sample, which brings some uncertainties in a synthesis process, such as the phenomenon of “wasteland, on which there is no nucleation and growth of diamond”. Furthermore, the formation mechanism of wasteland was studied in detail. It indicates that the wasteland is inevitably exists in the synthesis sample, the distribution of growth region of the diamond with hex-octahedral is move to the center of the synthesis sample from near the heater as the power increasing, and the growth conditions of high quality diamond is locate at the center of the synthesis sample. This work can offer suggestion and advice to the development and optimization of a diamond production process.

Stealth technology plays an important role in modern military conflicts, and because of its many practical advantages, plasma stealth technology has gained a lot of attention. In this paper, we describe our study of the reflection and absorption characteristics of waves propagating in multilayer plasma slabs. Our results show that positive effects on the attenuation can be obtained by optimizing the plasma parameters and by increasing the number of plasma layers. We also found that multilayer plasma slabs can effectively widen absorption bands, especially for low frequency bands.

Bulk metallic glasses (BMGs) with large supercooled liquid region are promising materials for superplastic forming. In this paper, we demonstrate a microstructure-based strategy to pinpoint the composition with the largest supercooled liquid region in La86−xAl14Cux (x=16 at%–20 at%) metallic glass system. By monitoring the changes in crystallization behavior of the glassy alloys with composition to search for the alloys exhibiting eutectic crystallization, the glassy alloys with the largest supercooled liquid region in the given alloy system can be found. The metallic glasses with Cu contents of 16 at%–19 at% exhibited two crystallization peaks, and the primary crystallization product was identified to be α-La by means of DSC, XRD and TEM. The increase in Cu content resulted in the decay of the primary crystallization peak and the increase in onset temperature of crystallization, leading to the enlargement of supercooled liquid region. By further suppressing the α-La primary crystallization with increasing Cu content up to 20 at%, the eutectic crystallization of α-La and LaCu13 through one crystallization reaction occurred upon heating, where the largest supercooled liquid region of 65 K for La66Al14Cu20 glassy alloy was located. This study indicats that, in a given glassy alloy system, a larger supercooled liquid region can be achieved by optimizing the alloy compositions to suppress the primary crystallization.