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BACKGROUND: Parachutists are generally recognized as a “high-risk” group among military personnel. However, the findings came mostly from data analysis without soldiers as subjects. OBJECTIVE: This study aimed to investigate the injury prevalence in Chinese paratroopers on-site and determine the relationship between injury and risk factors encountered during parachuting and land-based training. METHODS: This study consisted of a field study with questionnaire and an experiment on muscle load during the simulated training exercise of platform jumping with surface electromyography (EMG), in which 7230 paratroopers and 38 soldiers were involved respectively. Chi-square test was used for the injury rate analysis, ANOVA and t-test for comparison of EMG data, and logistic regression for the analysis of multiple factors. Taking both intensity and time into consideration, jump-years (J-yrs) was used as a complex indicator for exposure to parachuting. Either injury per 1000 jumps or injured persons per 100 soldiers were calculated as injury prevalence. RESULTS: The overall injury rate among Chinese parachutists was found to be 13.9 injuries per 1000 parachute jumps and 24.5% based on personnel. The person-based injury rate increased with the exposure level significantly (χ2 = 142.06, 2-sided, P

COVID-19 is a highly contagious virus. Blood test is one of effective methods for COVID-19 diagnosis. However, the issues of blood test are time-consuming and lack of medical staff. In this paper, four deep learning hybrid models are proposed to address these issues (i.e., CNN+GRU, CNN+Bi-RNN, CNN+Bi-LSTM, CNN+Bi-GRU). In addition, two best models, CNN and CNN+LSTM, from Turabieh et al. and Alakus et al., are implemented, respectively. Blood test data from Hospital Israelita Albert Einstein is used to train and test six models. The proposed best model, CNN+Bi-GRU, is accuracy of 0.9415, precision of 0.9417, recall of 0.9417, F1-score of 0.9417, AUC of 0.91, which outperforms the best models from Turabieh et al. and Alakus et al. Furthermore, the proposed model can help patients to get blood test results faster than traditional manual tests without errors caused by fatigue. The authors can envisage a wide deployment of proposed model in hospitals to alleviate the testing pressure from medical workers, especially in developing and underdeveloped countries.

The increasing resistance to metronidazole impaired the efficacy of Helicobacter pylori eradication, and increasing the dose of metronidazole was recommended to overcome low-level resistance. For patients infected with highly resistant strains, the current empirical treatments, which generally used metronidazole in double doses or more, appeared impossibly to overcome the resistance and would only increase the incidence of adverse effects.

In this study, a total of 339 mesoscale convective systems (MCSs) are obtained in North China using the temperature of brightness blackbody (TBB) data from the FY-2E in the warm season from 2010 to 2018. The number of meso-α-scale convective systems (MαCSs) is much more than that of meso-β-scale convective systems (MβCSs). The number of mesoscale elongated convective systems (MECSs) is more than that of mesoscale circular convective systems (MCCSs). Most MCSs occur in July and August, which have the widest influence range, the longest duration, and the strongest convection. The MαCS develops slowly and weakens rapidly. The diurnal variation of MαCSs presents a bimodal distribution, most of MαCSs form in the afternoon, while some of MαCSs form in the evening. The MCSs activities in the warm season of North China are concentrated in two belts, namely, the east–west-oriented belt along Henan Province, Shandong Province and the Yellow Sea, and the south–north-oriented belt along central-western Shandong, Tianjin City, the west of Bohai Sea and the northeast of Hebei Province. MCSs mainly move eastward, and only some MECSs move southwestward and northwestward. The easterly and northerly moving MCSs are mainly affected by the steering flow, while the southerly moving MCSs are mainly affected by storm propagation. The MCSs of North China mainly form in the high temperature, high humidity and high energy area, with favorable dynamic conditions, such as middle-level trough or vortex, low-level shear line, surface inverted trough or surface convergence line, and the terrain. Meanwhile, the MCS pregnant environment is often accompanied by low-level jet and relatively strong vertical wind shear.

Pregnancy and lactation are a window period during which interventions on mothers bring beneficial effects to newborns.

As an efficient electron and proton donor, reduced nicotinamide adenine dinucleotide (NADH) coenzyme holds great promises in enzymatic industry, however, the high cost of NADH regeneration and its stoichiometric consumption...

Polytetrafluoroethylene (PTFE) is extensively used in equipment used for manufacturing semiconductor components and wet etching equipment. However, achieving ideal dimensional accuracy when cutting PTFE is challenging. In this study, we performed cutting experiments using a curvilinear tool and analyzed cutting force, cutting temperature, groove width, and surface roughness in PTFE grooving. The results indicated that the cutting force was most notably affected by the feed rate in Stage I of grooving. The rate of change in cutting force was the largest in Stage II because of the increase in the tool contact area. In Stage III, the shear area of the rake face was the largest, and the cutting force tended to be stable. The groove width was measured with a minimum error rate of 0.95% at a feed rate of 0.05 mm/rev. Moreover, the groove exhibited a time—independent springback. The minimum groove surface roughness was 0.586 at a feed rate of 0.05 mm/rev. The ideal feed rate was 0.05 mm/rev with groove width, surface quality, and chip curl as the key parameters. The processing parameters obtained in this study can be applied to actual production for the optimization of manufacturing accuracy.

Selective attention is an efficient processing strategy to allocate computational resources for pivotal optical information. However, the hardware implementation of selective visual attention in conventional intelligent system is usually bulky and complex along with high computational cost. Here, programmable ferroelectric bionic vision hardware to emulate the selective attention is proposed. The tunneling effect of photogenerated carriers are controlled by dynamic variation of energy barrier, enabling the modulation of memory strength from 9.1% to 47.1% without peripheral storage unit. The molecular polarization of ferroelectric P(VDF-TrFE) layer enables a single device not only multiple nonvolatile states but also the implementation of selective attention. With these ferroelectric devices are arrayed together, UV light information can be selectively recorded and suppressed the with high current decibel level. Furthermore, the device with positive polarization exhibits high wavelength dependence in the image attention processing, and the fabricated ferroelectric sensory network exhibits high accuracy of 95.7% in the pattern classification for multi-wavelength images. This study can enrich the neuromorphic functions of bioinspired sensing devices and pave the way for profound implications of future bioinspired optoelectronics.

β-ammonium tetramolybdate [β-(NH4)2Mo4O13] is an important product of molybdenum metallurgy because of its uniform crystal structure and excellent thermal stability. The yield of molybdenum strip produced with β-(NH4)2Mo4O13 as raw material and various processing properties have been significantly improved. However, the crystallization process of β-(NH4)2Mo4O13 is very complex, including neutralization, polymerization, nucleation, and crystal growth stages, resulting in a variety of polymerization morphology. In this work, a concentric structure reactor was used to segment these stages with directional regulation of each stage. Residence time distribution (RTD) was used to evaluate the simulation of flow field characteristics in the concentric structure reactor. Determination of the influence of inlet-outlet positions, size and position of paddle, and baffle setting on the fluid behavior in a single tank suggested measures to improve the abnormal flow condition and reduce the dead zone volume fraction. In the concentric structure reactor, the dead zone volume fraction was only 2.36% when the clapboards were arranged alternately in an up-down design, using an inlet flow rate of 100 mL/min. β-(NH4)2Mo4O13 was prepared continuously by adding aqueous ammonia and product slurry for crystallization in the concentric structure reactor.

On the morning of July 21, 2017, a localized rainstorm event occurred in the Shijiazhuang area of Hebei Province, with the heavy rain mainly concentrating in the Shijiazhuang urban area and its eastern and northern parts. But this rainstorm process was omitted by both numerical and subjective forecasts. In this paper, the triggering mechanisms of the mesoscale convective systems that have caused this localized rainstorm are analyzed by using the intensified surface observation data, Doppler radar data, the four-dimensional variational Doppler radar analysis system (VDRAS), the National Centers for Environmental Prediction (NCEP) reanalysis data and the ERA5 reanalysis. The observation analysis shows that when the heavy rain was occurring, the Shijiazhuang area was controlled by the western Pacific subtropical high, and the high temperature and high humidity environment has provided favorable vapor, thermal and energy conditions for the rainfall. Three key factors are responsible for the triggering of this severe convective weather. First, the strong thunderstorm high pressure and cold pool formed in Qinhuangdao and Tangshan areas in the northeastern Hebei. The surface wind field was affected by the pressure-gradient force generated by the thunderstorm high pressure, and consequently the northeasterly wind gradually strengthened, which guided the tongue-shaped cold pool to gradually move southwestward to the northern Shijiazhuang. Thus, a long lasting cold-warm boundary (the leading edge of the cold tongue) was formed in the key precipitation area, which provided low-level convergence and the ascending motion for the occurrence and development of this severe convective weather. Second, the northeasterly wind in the east side of Taihang Mountain was forced to ascend by the topography of Taihang Mountain, which strengthened the upward motion. Third, as the direction of the Taihang Mountains shifts from a northeast–southwest direction to a northwest–southeast direction in the west side of Shijiazhuang, the surface northeasterly airflow is changed to a northwesterly airflow here, forming a convergence in the key area of precipitation in front of the mountain. Thus, an unstable vertical structure that features low-level convergence and middle-level divergence is formed. The above three factors work together in the region where the severe convections occurred, and triggered the release of the conditional instability energy, finally resulting in this short-time heavy rain. The results indicate that in the forecast of severe convections in midsummer, we should pay extra attention to the complex terrain and the effects of the cold pool.

BackgroundMusculoskeletal disorders (MSDs) are critical occupational and social problems. With the improvement of production mechanization and automation, and the widespread application of computers, more occupations are exposed to static postures and load. This study explored the role of inflammation in the association between static postures exposure and MSDs.MethodsThis study adopted a prospective nested case-control design in which 66 lower back MSDs cases and 66 healthy controls were selected from a cohort study of university employees. The personal information, postural load, musculoskeletal symptoms, pressure pain thresholds (PPTs), and inflammatory cytokines were collected. Logistic and linear regressions were used to investigate the association among postural load, inflammatory cytokines, and lower back MSDs. Mediation analysis was used to calculate the mediation effect.ResultsThe results of logistic and linear regressions showed that postural load and inflammatory cytokines were positively associated with lower back MSDs (P < 0.05), and postural load was positively associated with inflammatory cytokines (P < 0.05). Further, mediation analysis showed that the mediation effect of postural load on the lower back MSDs through TNF-α was 0.073 (95%CI: 0.025–0.128), and the mediation effect of posture load on the lower back MSDs through IL-6 was 0.098 (95%CI: 0.041–0.179), respectively.ConclusionStatic postures were associated with the occurrence of MSDs through inflammatory cytokines, and low-level inflammation may be a critical early event in the generation of MSDs. This study may help bridge the gap of potential mechanisms linking static postures to increased risks of MSDs, and provide new evidence for targeted protection against the global increasing MSDs.

The vast majority of people with cystic fibrosis (CF) are now eligible for CF transmembrane regulator (CFTR) modulator therapy. The remaining individuals with CF harbor premature termination codons (PTCs) or rare CFTR variants with limited treatment options. Although the clinical modulator response can be reliably predicted using primary airway epithelial cells, primary cells carrying rare CFTR variants are scarce. To overcome this obstacle, cell lines can be created by overexpression of mouse Bmi-1 and human TERT (hTERT). Using this approach, we developed 2 non-CF and 6 CF airway epithelial cell lines, 3 of which were homozygous for the W1282X PTC variant. The Bmi-1/hTERT cell lines recapitulated primary cell morphology and ion transport function. The 2 F508del-CFTR cell lines responded robustly to CFTR modulators, which was mirrored in the parent primary cells and in the cell donors' clinical response. Cereblon E3 ligase modulators targeting eukaryotic release factor 3a (eRF3a) rescued W1282X-CFTR function to approximately 20% of WT levels and, when paired with G418, rescued G542X-CFTR function to approximately 50% of WT levels. Intriguingly, eRF3a degraders also diminished epithelial sodium channel (ENaC) function. These studies demonstrate that Bmi-1/hTERT cell lines faithfully mirrored primary cell responses to CFTR modulators and illustrate a therapeutic approach to rescue CFTR nonsense mutations.

We designed three cholesterol-modified carboxylated pullulan (CHSP) polymers modified with different degrees of substitution (DS). Nuclear magnetic resonance (NMR) was used to characterize CHSP pol...

Enormous synaptic devices are required to build a parallel, precise, and efficient neural computing system. To further improve the energy efficiency of neuromorphic computing, a single high-density synaptic (HDS) device with multiple nonvolatile synaptic states is suggested to reduce the number of synaptic devices in the neural network, although such a powerful synaptic device is rarely demonstrated. Here, a photoisomerism material, namely, diarylethene, whose energy level varies with the wavelength of illumination is first introduced to construct a powerful HDS device. The multiple synaptic states of the HDS device are intrinsically converted under UV-vis regulation and remain nonvolatile after the removal of illumination. More importantly, the conversion is reconfigurable and reversible under different light conditions, and the synaptic characteristics are comprehensively mimicked in each state. Finally, compared with a two-layer multilayer perceptron (MLP) architecture based on static synaptic devices, the HDS device-based architecture reduces the device number by 16 times to achieve a minimalist neural computing structure. The invention of the HDS device opens up a revolutionary paradigm for the establishment of a brain-like network.

Driven by important megatrends such as cloud computing, artificial intelligence, and the Internet of Things, as a device used to store programs and data in computing systems, memory is struggling to catch up with the explosive growth of data and bandwidth requirements in the system. However, the “storage wall” between non-volatile memory and volatile memory retards the further improvement of modern memory computing systems. Herein, a quasi-volatile transistor memory based on organic polymer/perovskite quantum dot blend was fabricated using the vertical transistor configuration. Contributing to vertical structure and appropriate doping ratio of blend film, the quasi-volatile memory device displayed 1,560 times longer data retention time (> 100 s) with respect to the dynamic random access memory and fast data programming speed (20 µs) in which was far more quickly than that of other organic non-volatile memories to fill the gap between volatile and non-volatile memories. Moreover, the device retention characteristics could be further promoted under the photoelectric synergistic stimulation, which also provided the possibility to reduce electric writing condition. Furthermore, the quasi-volatile memory device showed good electrical performance under bending conditions. This work provides a simple solution to fabricate multi-level quasi-volatile memory, which opens up a whole new avenue of “universal memory” and lays a solid foundation for low power and flexible random access memory devices.

The transmembrane Hsp40 DNAJB12 and cytosolic Hsp70 cooperate on the endoplasmic reticulum’s (ER) cytoplasmic face to facilitate the triage of nascent polytopic membrane proteins for folding versus degradation. N1303K is a common mutation that causes misfolding of the ion channel CFTR, but unlike F508del-CFTR, biogenic and functional defects in N1303K-CFTR are resistant to correction by folding modulators. N1303K is reported to arrest CFTR folding at a late stage after partial assembly of its N-terminal domains. N1303K-CFTR intermediates are clients of JB12-Hsp70 complexes, maintained in a detergent-soluble state, and have a relatively long 3-h half-life. ER-associated degradation (ERAD)-resistant pools of N1303K-CFTR are concentrated in ER tubules that associate with autophagy initiation sites containing WIPI1, FlP200, and LC3. Destabilization of N1303K-CFTR or depletion of JB12 prevents entry of N1303K-CFTR into the membranes of ER-connected phagophores and traffic to autolysosomes. In contrast, the stabilization of intermediates with the modulator VX-809 promotes the association of N1303K-CFTR with autophagy initiation machinery. N1303K-CFTR is excluded from the ER-exit sites, and its passage from the ER to autolysosomes does not require ER-phagy receptors. DNAJB12 operates in biosynthetically active ER microdomains to triage membrane protein intermediates in a conformation-specific manner for secretion versus degradation via ERAD or selective-ER-associated autophagy.

Leaching of scheelite ore with phytate is a novel and clean hydrometallurgical method of isolating tungsten, which achieves efficient decomposition under atmospheric pressure. However, realizing the separation and recycling of tungstate and phytate has become an additional and subsequent problem, which had not been encountered in the traditional tungsten metallurgical process. In determining ways to overcome this obstacle, ion exchange methods exhibit promising routes to separate tungstate and phytate. Before performing this new method, it is prudent to study the kinetics of the ion exchange process. The effects of WO3 concentration, phytate concentration, resin particle size, and reaction temperature were investigated. Results show that a pseudo-second-order model can describe the adsorption kinetic behavior of phytate and tungstate in the mixed solution. The apparent activation energies of WO3 and phytate, based on the Arrhenius expression, were calculated as 21.4 kJ/mol and 21.8 kJ/mol, indicating that the adsorption processes of phytate and tungstate are diffusion-controlled.

Vertical transistors have attracted enormous attention in the next-generation electronic devices due to their high working frequency, low operation voltage and large current density, while a major scientific and technological challenge for high performance vertical transistor is to find suitable source electrode. Herein, an MXene material, Ti3C2Tx, is introduced as source electrode of organic vertical transistors. The porous MXene films take the advantage of both partially shielding effect of graphene and the direct modulation of the Schottky barrier at the mesh electrode, which significantly enhances the ability of gate modulation and reduces the subthreshold swing to 73 mV/dec. More importantly, the saturation of output current which is essential for all transistor-based applications but remains a great challenge for vertical transistors, is easily achieved in our device due to the ultra-thin thickness and native oxidation of MXene, as verified by finite-element simulations. Finally, our device also possesses great potential for being used as wide-spectrum photodetector with fast response speed without complex material and structure design. This work demonstrates that MXene as source electrode offers plenty of opportunities for high performance vertical transistors and photoelectric devices.

Inspired by biological neuromorphic systems, which can simultaneously perceive, remember, and process enormous information through parallel, energy-efficient processes, artificial synaptic transistors have shown great potential in paving a way to overcome the von Neumann bottleneck for neuromorphic computing. Artificial synapses capable of effectively emulating both the excitatory postsynaptic current (EPSC) and inhibitory postsynaptic current (IPSC) responses, and particularly reconfiguration, are crucial for building neuromorphic systems with desirable versatility. However, it is still challenging to realize emblematical neurobehavior in unipolar transistors owing to the unbalanced carrier concentration. Therefore, for the first time, a facile light-adjustable organic photoelectric synaptic transistor based on bulk heterojunction blends is developed. In addition, typical synaptic properties including the excitatory/inhibition postsynaptic current, paired pulse facilitation/inhibition, frequency-dependent characteristics, the transformation from short-term to long-term plasticity are successfully simulated and modulated by light illumination. Moreover, the mechanism of light illumination on the neuroplasticity of our synaptic device is discussed. Notably, the recognition accuracy of our synaptic device can be efficaciously modulated by the light intensity and achieves 86% accuracy with appropriate light exposure conditions. The artificial synaptic devices based on bulk heterojunction open up a whole new path for the urgent need of neuromorphic computation, in which light illumination can be utilized for modifying the circuit learning rate.

The great interest in using nanoparticles (NPs) for biomedical applications is transversal to various materials despite the poorly understood correlation between their physicochemical properties and effects on the immune system. NPs, such as gold and Fe3O4, are generally regarded as safe, but the immunotoxicological profile of Au/Fe3O4 composite NPs with different physicochemical properties is not well documented. This study investigated the biological impact of Au/Fe3O4 composite NPs with different morphologies (spherical core-shell and flower-like) and shell composition in vitro to analyze their potential cytotoxic effects and inflammatory responses on RAW 264.7 cells. Au/Fe3O4 composite NPs with a flower-like structure (FLNPs) induce a pronounced reduction in cell viability compared with Au/Fe3O4 composite NPs with a spherical core-shell structure (CSNPs). The increased production of reactive oxygen species, which damages cellular membranes, might contribute to the cytotoxicity effect of FLNPs. However, CSNPs presented more RAW 264.7 cell adhesion and uptake than FLNPs. Remarkably, a significant TNF-α release was observed with CSNP treated RAW 264.7 cells other than that of FLNPs. Protein corona analysis revealed the adsorption of a distinct amount and profile of proteins on the surface of CSNPs and FLNPs. Given the similar particle size and ζ-potential of CSNPs and FLNPs under the cell culture condition, results indicate that the impact of Au/Fe3O4 composite NPs on the macrophage activity highly depends on their morphology, shell composition and protein corona profile.

High-fidelity and high temporal precision synaptic propagation, which are mainly determined by the decay kinetics of synaptic currents, are crucial for neuromorphic computing that has emerged as a promising avenue towards building the next generation of intelligent computing systems. However, the precise control of the decay kinetics of synaptic currents in the fixed synaptic device has rarely been reported in the synaptic transistors. In this work, a type of synaptic field-effect transistors (SFETs) based on the polymer bulk p–n heterojunction (BHJ) was invented, in which decay constant was able to be well controlled. The essential functionalities of synapses, such as excitatory/inhibitory postsynaptic current (EPSC/IPSC) and paired-pulse facilitation (PPF), were successfully used in this artificial synaptic device. More importantly, small angle-neutron scattering (SANS) was used to elucidate the current decay mechanism of these devices, which was found to be significantly impacted by the aggregation and connectivity of n-type fullerene. This work provided a universal synaptic transistor device with tunable decay constant, shedding light on the future development of high-fidelity and high temporal precision synaptic propagation neuromorphic computing systems.

Organic phototransistors with high sensitivity and responsivity to light irradiance have great potential applications in national defense, meteorology, industrial manufacturing, and medical security. However, undesired dark current and photoresponsivity limit their practical applications. Here, a novel vertical organic phototransistor combined with ferroelectric materials is developed. The device structure has nanometer channel length, which can effectively separate photogenerated carriers and reduce the probability of carrier recombination and defect scattering, thus improving the device performance of phototransistors. Moreover, by inserting the poly(vinylidene fluoride-co-trifluoroethylene) (P(VDF-TrFE)) ferroelectric layer, the Schottky barrier at the interface between the semiconductor and source can be adjusted by the polarization of the external electric field, which can effectively reduce the dark current of the phototransistor to further improve the device performance. Therefore, our phototransistors exhibit a high photoresponsivity of more than 5.7 × 105A/W, an outstanding detectivity of 1.15 × 1018 Jones, and an excellent photosensitivity of 5 × 107 under 760 nm light illumination, which are better than those of conventional lateral organic phototransistors. This work provides a new approach for the development of high-performance phototransistors, which opens a new pathway for organic phototransistors in practical application.