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Pumping coolant or using pulse flow through microchannels with novel structures on microelectronic devices is suitable for high heat flux dissipation and sensor development. This study proposes a novel microchannel designed as a series of biomimetic bark channel networks. Simulation and experimental testing of temperature distribution and heat transfer performance are conducted under different working conditions, including various fluid parameters. The results show that combining biomimetic bar microchannel and pulsation flow can improve heat transfer performance. The effect of pulsating flow frequency on the temperature is only evident outside the range of 10 mm from the inlet. Compared with non-slip boundaries, the boundary slip of pulsating flow slightly enhances heat transfer. Pulsating flow has an optimal frequency, minimizing thermal resistance for different inlet temperatures.

Due to cross-linked structures, thermoset polymers cannot provide sufficient free volume for nanofillers to maneuver. Related composites are therefore governed by phase separation where filler-deficit regions become mechanical weakness. This work discovers that carbon nanotubes can be redispersed in thermoset polymer through heat treatments, thus, enhancing strength, thermal, and electrical conductivity of composites. Experiments carried out on a different thermoset matrix gives a similar trend where heating induced tube displacement is also verified by molecular dynamic simulations and piezo-resistivity tests.

The crystal structures of zirconium diboride have been thoroughly explored up to 200 GPa by applying the particle‐swarm optimization technique in company with first‐principles calculations. The hexagonal ZrB2 with space group of P6/mmm is always stable in the pressure region of 0–200 GPa. Structurally, this structure consists of the intriguing regular ZrB12 hexagonal column and the planar hexagonal B ring unit. In addition, the stable AlB2–ZrB2 configuration is mechanically and dynamically stable as confirmed by the respective calculations of elastic constants and phonon dispersion curves. The hardness values exhibit a shrinking variation upon further compression, which mainly originates from the decreasing brittleness and degree of the directionality of the covalent bonds with the growing pressure. Interestingly, the analyses of the Poisson's ratio, density of states, electron location function and Bader charge substantiate that a combination of covalent and ionic characters exists in the AlB2–ZrB2 crystalline with the formidable covalent interaction in the BB bonds, and partially covalent and partially ionic interactions in the ZrB bonds. The hardness value for this phase unexpectedly reaches 45.41 GPa under ambient pressure, higher than the lower limit of superhard materials. [ABSTRACT FROM AUTHOR]

Under the global wave of brain science development, neurobiology, an important part of “brain project” needs strong support from existing neurobiologists and new blood infusion. Therefore, teaching of neuroscience becomes crucial. Combined with the characteristics of neurobiology teaching and scientific research in military colleges, a mode of “scientific research back-feeding teaching” was carried out. Through the integration of scientific spirit, scientific thinking, support of scientific research platform and off-curricular scientific projects into the multi-level teaching practice, the effect of scientific research back-feed teaching is significant, and the back feeding of scientific research to teaching greatly stimulates the students'learning interest of brain science, and improves the teaching quality, which also greatly supports the training of brain science talents.

A 4Kx8 innovative fuse (I-fuse)1 one-time programmable (OTP) based on a 1R1T metal-gate fuse with a strictly electromigration program mode has a 0.744 μm2 cell and 111 μm × 411 μm macro on 22-nm FD-SOI. This macro can be programmed at 1.0-1.45 V with

Recent experimental and theoretical studies have shown that a La-H system displays remarkable superconducting properties, and it is also possible to improve the superconducting state by introducing other elements into this system. In this study, we systematically investigated the crystal structures and physical properties of an H–S–La system by using first-principles calculations combined with the CALYPSO structure exploration technique. We predicted four stable stoichiometries containing H2SLa, H3SLa, H4Sla, and H6SLa. These compounds undergo a series of phase transitions under 50–300 GPa. The bonding characters and electronic properties were calculated. It was found that Cm-H2SLa, C2/c-H2SLa, and Cmcm-H6SLa exhibit good metallic nature, which stimulates us to further study their superconducting properties. The calculated superconducting transition temperatures (Tc) of Cm-H2SLa, C2/c-H2Sla, and Cmcm-H6SLa are 15.0 K at 200 GPa, 6.9 K at 300 GPa, and 23.6 K at 300 GPa, respectively. [ABSTRACT FROM AUTHOR]

In this paper, we perform unbiased structure searches combined with first-principles calculations to predict the stable structures and possible superconductivity of ErHn (n = 4~6) under pressures of 50~300 GPa. Two novel compounds, ErH4 and ErH6, are identified as thermodynamically and dynamically stable above 50 GPa; ErH4 and ErH6 can stabilize in clathrate structures with the I4/mmm and Im 3 ¯ m space groups, respectively. An analysis of the electronic density of states (DOS) suggests the metallic nature of the two phases. Then, the superconducting critical temperature (Tc) is estimated using the Allen–Dynes modified McMillan equation; the results are 130.9~181.2 K for Im 3 ¯ m-ErH6 at 100~300 GPa, and 74.4~79.8 K for I4/mmm-ErH4 at 150~300 GPa. The resultant high Tc superconductivity in this system can be traced back to the combination of high density of states at the Fermi level and strong electron–phonon interactions. [ABSTRACT FROM AUTHOR]

The micro-electromechanical system (MEMS) safety-and-arming (S&A) device has the features of integration and miniaturization, which is one of the important directions of weapon development. Confined by the fabrication process, the silicon-based devices are too fragile, and the metal-based devices are low precision. In order to solve the contradiction between high precision and high structure strength, a metal/silicon composite structure is proposed in this paper, and a hybrid fabrication process is introduced. This new method mainly consists of metal sputtering, electroplating, and (inductively−coupled-plasma) ICP etching. As the resolution of the thick dry film is limited, the process of a femtosecond laser is applied to refine the structure, and the Ni plate (a block of 1 mm × 3 mm × 0.3 mm with a cavity of ϕ 0.85 mm × 0.3 mm in the center) is fabricated on the silicon-on-insulator (SOI) wafer successfully. After the double sides are etched by ICP, the SOI wafer is immersed in a buffered-oxide-etch (BOE) etchant to remove the buried layer. The cover plate acts as the encapsulation and is bonded with the SOI wafer by the epoxy glue. Then, the temporary support beam of the device is broken by the probe, and the suspended composite structure can be fully released. The hybrid process is the integration of the silicon-based process and the metal-based process, which can combine the advantages of both high precision and a high structure strength. The process proposed here is suitable for the application of weapon miniaturization.

The design and characterization of microelectromechanical systems (MEMS) based on-chip SAD (Safety and Arming Device) are proposed. An encryption system has been integrated into the device to enhance its reliability during the electromagnetic interference. The conversion between safe status and arm status is reversible due to the bidirectional actuation design of the slider and pawl on the SOI (Silicon on Insulator) chip, being driven by the chevron electrothermal actuators. The width of each tooth on the slider, which contains coding information, is different from that of its adjacent neighbor. Additionally, the different teeth width, respectively 32 μm, 82 μm, requiring different decoding displacement of 100 μm and 150 μm, corresponds to the different decoding voltage of 13.5 V and 14.8 V. The travel range of interrupter in the SAD will only be limited by the chip dimension and be able to cover the motion of ±1 mm in the present research, due to the capability of motion retention. Finally, the SAD is integrated with a copper azide exploding chip to measure the average velocity of the titanium flyer for the application feasibility validation.

Using density functional theory and semiclassical Boltzmann transport equation, the lattice thermal conductivity and electronic transport performance of monolayer SnI2 were systematically investigated. The results show that its room temperature lattice thermal conductivities along the zigzag and armchair directions are as low as 0.33 and 0.19 W/mK, respectively. This is attributed to the strong anharmonicity, softened acoustic modes, and weak bonding interactions. Such values of the lattice thermal conductivity are lower than those of other famous two-dimensional thermoelectric materials such as MoO3, SnSe, and KAgSe. The two quasi-degenerate band valleys for the valence band maximum make it a p-type thermoelectric material. Due to its ultralow lattice thermal conductivities, coupled with an ultrahigh Seebeck coefficient, monolayer SnI2 possesses an ultrahigh figure of merits at 800 K, approaching 4.01 and 3.34 along the armchair and zigzag directions, respectively. The results indicate that monolayer SnI2 is a promising low-dimensional thermoelectric system, and would stimulate further theoretical and experimental investigations of metal halides as thermoelectric materials. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the cost-effectiveness of camrelizumab immunotherapy versus docetaxel or irinotecan chemotherapy as second-line therapy for advanced esophageal squamous cell carcinoma (ESCC), which was evaluated in the ESCORT trial. Materials and Methods: A partitioned survival model was developed to reflect the costs and effectiveness of the ESCORT trial. The clinical efficacy data, safety data, and health-related costs and utilities were derived from published data from clinical trials or health administration departments in China. Adverse event-related costs, drug administration, and other expenses were derived from a single center of Fujian Medical University Cancer Hospital in 2021. All survival analyses were performed with SPSS software. Overall survival was estimated with the Kaplan–Meier method, and progression-free survival was estimated with the life table method. Sensitivity analyses were conducted to assess the uncertainty of the model. Incremental cost, quality-adjusted life years (QALYs), and the incremental cost-effectiveness ratio (ICER) were calculated. Results: Camrelizumab therapy had 0.232 QALYs at an incremental cost of USD$9959.44 compared with the chemotherapy group with 0.158 QALYs at an incremental cost of USD$8601.67. The ICER was USD$18393.12/QALY. Probabilistic sensitivity analyses showed that when the willingness-to-pay threshold reached USD$31200/QALY, which is nearly three times the Chinese gross domestic product per capita, camrelizumab had an 80% possibility of being cost-effective versus docetaxel or irinotecan chemotherapy. Conclusion: Camrelizumab is a cost-effective option compared with docetaxel or irinotecan chemotherapy in patients with advanced ESCC as second-line therapy in China. [ABSTRACT FROM AUTHOR]

Purpose: Comorbid anxiety and depression in people with epilepsy (PWE) are highly prevalent and contribute to low quality of life (QOL) and may even lead to poor outcomes of epilepsy. Among the various factors that affect these negative emotional comorbidities, possible gender differences remain poorly understood and are often neglected. This research aimed to determine whether there are discrepancies in the incidence and influence factors of anxiety and depression between men and women with epilepsy in a hospital in northwest China. Methods: A total of 158 adult PWE (female: N = 65; 41.1%) completed self-report questionnaires, including the Self-rating Anxiety Scale (SAS), the Self-rating Depression Scale (SDS), the Chinese version of the Quality of Life in Epilepsy-31 (QOLIE-31) inventory and the Pittsburgh Sleep Quality Inventory (PSQI). The comparison between male and female PWE was made by regression analysis. Results: For the prevalence of anxiety and depression in PWE, no gender difference was found in this study. However, the moderating factors of psychiatric comorbidities were significantly different between men and women: male PWE with comorbid anxiety were more likely to be affected by sleep quality, while anxiety symptoms in female PWE were closely associated with the frequency of seizures. Education years and QOL social function were significant indicators of depression in male PWE but not in female PWE. The important and common predictor for anxiety and depressive symptoms in PWE was QOL energy/fatigue, with male patients being more affected. Conclusion: For the PWE included in this study, the incidence of comorbid anxiety and depression in PWE was similar for men and women, but the moderating factors affecting comorbid anxiety and depressive disorders differed between genders: male PWE were more likely to be affected by psychosocial factors, while female PWE were more influenced by epilepsy itself. This exploration suggests that gender-specific health care should be considered in epilepsy therapy to improve the psychiatric condition and QOL of PWE, and different treatments should be conducted for male and female PWE to prevent negative emotional comorbidities. [ABSTRACT FROM AUTHOR]

Twenty-seven compounds, including a new diarypropane and two new lignans were isolated from the twigs and leaves of Endocomia macrocoma. Their structures were elucidated by spectroscopic analysis. Cytotoxicity evaluation of the new compounds against five human tumor lines showed no inhibitory effects. [ABSTRACT FROM AUTHOR]

Two new dibenzylbutyrolactol lignans and three known dibenzylbutyrolactone lignans were isolated from the twigs and leaves of Horsfieldia kingii. Their structures were elucidated by spectroscopic analysis. Cytotoxicity evaluation of these compounds against five human tumour lines showed no inhibitory effects. [ABSTRACT FROM AUTHOR]

Purpose: This study’s aim was to investigate the beneficial effects of branched-chain amino acids (BCAAs) on the neuronal survival and axon regeneration of retinal ganglion cells (RGCs) after optic nerve (ON) transection. Method: The experimental rats received daily BCAA injections through the caudal vein after left intra-orbital ON transection. Neuroprotection was evaluated by counting Fluorogold-labeled RGCs. The role of mammalian target of rapamycin (mTOR) pathway activation in promoting RGC survival was studied after rapamycin administration. Moreover, a peripheral nerve (PN) graft was transplanted onto the transected ON to study the effects of BCAAs on axon regeneration of injured RGCs. Results: Our results showed that BCAAs alleviated the death of RGCs 7 and 14 days after ON transection, accompanied by an activation of mTOR pathway in RGCs. Blocking mTOR pathway with rapamycin eliminated such neuroprotective effects of BCAAs. Moreover, BCAAs also promoted axon regeneration of injured RGCs into a PN graft. Conclusion: Our results suggest a neuroprotection of BCAAs through the activation of mTOR pathway. BCAAs also have a beneficial effect on axon regeneration of injured RGCs. Therefore, BCAAs could be considered for the clinical treatment of ON injury. [ABSTRACT FROM AUTHOR]

Five compounds, including a new dimeric diarylpropane, were isolated from the petroleum ether extract of the twigs and leaves of Horsfieldia tetratepala. The structures of these compounds were elucidated by spectroscopic analysis. Moreover, the antiproliferative activities of these compounds were tested on cancer cell lines, but none is active. [ABSTRACT FROM AUTHOR]

Aescin has many physiological functions that are highly relevant to spinal cord injury (SCI), including anti-inflammation, anti-oxidation, anti-oedema, and enhancing vascular tone. The present study investigated the putative therapeutic value of aescin in SCI, with a focus on its neuroprotective, anti-inflammatory, and anti-oxidative properties. Sodium aescinate (1.0 mg/kg body weight) or equivalent volume of saline was administered 30 min after injury by intravenous injection, with an additional dose daily for seven consecutive days after moderate SCI in rats. After contusion injury of the 8th thoracic (T8) spinal cord, aescin-treated rats developed less severe hind limb weakness than saline controls, as assayed by the Basso-Beattie-Bresnahan scale, the beam walking test, and a footprint analysis. The improved locomotor outcomes in aescin-treated rats corresponded to markedly decreased immune response, oxidative stress, neuronal loss, axon demyelination, spinal cord swelling, and cell apoptosis, measured around T8 after impact. Our data suggest aescin treatment as a novel, early, neuroprotective approach in SCI. Given the known safety of aescin in clinical applications, the results of this study suggest that it is a good candidate for SCI treatment in humans. [ABSTRACT FROM AUTHOR]

To mimic multilevel nerve root compression and intervertebral foramina stenosis in human, we established a new animal model of the chronic compression of unilateral multiple lumbar DRGs (mCCD) in the rat. A higher occurrence of signs of spontaneous pain behaviors, such as wet-dog shaking and spontaneous hind paw shrinking behaviors, was firstly observed from day 1 onward. In the meantime, the unilateral mCCD rat exhibited significant bilateral hind paw mechanical and cold allodynia and hyperalgesia, as well as a thermal preference to 30°C plate between 30 and 35°C. The expression of activating transcription factor 3 (ATF3) was significantly increased in the ipsilateral and contralateral all-sized DRG neurons after the mCCD. And the expression of CGRP was significantly increased in the ipsilateral and contralateral large- and medium-sized DRG neurons. ATF3 and CGRP expressions correlated to evoked pain hypersensitivities such as mechanical and cold allodynia on postoperative day 1. The results suggested that bilateral neuropathy of primary sensory neurons might contribute to bilateral hypersensitivity in the mCCD rat. [ABSTRACT FROM AUTHOR]

Based on the layout principles of inlet and outlet pipes, using the cavity acoustic modes to design muffler can get good acoustic attenuation, and for the inlet and outlet pipes are not coaxial, the pressure loss is larger when it is caused by the blocked air flow. Taking the expansion chamber and flow-reversing chamber as examples, firstly, comparative study about the effects of chamfer transition and circular arc transition on the pressure loss and transmission loss were made based on the finite element method. The results showed that the smooth transition of outlet pipe could decrease the pressure loss and did not affect the transmission loss at the same time; moreover, the properties of muffler with circular arc transition were much better than those of chamfer transition. On this basis, the coupling influences of transition circular arc radius and muffler size on the pressure loss and transmission loss were analyzed. It turned out that the transition circular arc of outlet pipe almost had no effect on the transmission loss but could effectively decrease pressure loss; moreover, this is a universal law and will not be changed with the change of type and size of the muffler. And with the increase of transition circular arc radius, the change rates of the pressure loss were decreasing. Further, under the premise of keeping the overall size, an automobile muffler was made a preliminary improvement by applying the layout principles of inlet and outlet pipes based on the cavity acoustic modes. After the preliminary improvement, the average transmission loss was increased by 15.8 dB in the frequency range of 750-1500 Hz, but the pressure loss was increased by 7.78% with the inlet velocity of 60 m/s. In order to decrease the pressure loss on the base of good acoustic attenuation performance, the further improvement of car muffler was made. The first chamber and third chamber of muffler could be seen as two simple flow-reversing mufflers, and 10 mm transition circular arcs were added at the entrance of outlet pipes on the basis of the preliminary improvement. Compared with the original muffler, the average transmission loss of final improved muffler in the frequency range of 750-1500 Hz was increased by 15.3 dB and slightly lower than that of preliminary improved muffler, however, the pressure loss was reduced by 25.20% with the inlet velocity of 60 m/s. In conclusion, the properties of muffler have been greatly improved after the further improvement. Integrated use of the layout principle of inlet and outlet based on the cavity acoustic modes and the effect laws of outlet pipe transition circular arc on the pressure loss can guide the muffler design. [ABSTRACT FROM AUTHOR]

Effects of charge state and interatomic distance on the magnetic properties of C-doped MgO system are explored by a revised PBE (PBEsol) functional plus U method. Both PBEsol and PBEsol + U results demonstrate that single neutral C substituted at the O site can induce a stable magnetic moment of 2 μ B into the doped system. We mainly find that the size of the magnetic moment is determined by the charge states of the C dopant and strongly depended on the distance between two C dopants. These results are expected to stimulate future experimental work on the dilute magnetic semiconductors. [ABSTRACT FROM AUTHOR]

To the multi-parameter optimization problem of SVM with mixtures kernels, this paper proposed an improved chaotic particle swarm optimization (ICPSO) to find the best combination of the basic parameters (penalty parameter, kernel parameter et.) and mixtures adjustable kernels parameter of SVM. The experimental results further demonstrate that the proposed method can effectively search the best parameters combination, and has better generalization ability and better regression effect. This method has good modeling and higher prediction accuracy for coal and gas outbursts. [ABSTRACT FROM AUTHOR]