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Inconsistent online reviews, which affect customers' purchase intention, are gaining increasing attention. In this paper we analyzed the mechanism of inconsistent online reviews that are posted by the same reviewer on customers' purchase intention. Our research was based on a psychological distance theory perspective, specifically in three dimensions: temporal distance, social distance, and hypothetical distance. Our findings were as follows: First, inconsistent online reviews had a significant negative effect on customers' purchase intention, and product type (experience vs. search) played a moderating role. Second, when customers faced inconsistent online reviews, temporal, social, and hypothetical distance significantly affected their purchase intention but this differed according to product type. The effect of temporal distance was more significant for a search product than it was for an experience product; however, social distance and hypothetical distance had more significant effects for the experience product. Our research conclusions enrich the literature on online reviews and provide suggestions for sellers on e-commerce platforms to manage inconsistent reviews according to product type.

The heat treatment process is a vital step for manufacturing high-speed railway spring fasteners. In this study, orthogonal experiments were carried out to obtain reliable optimised heat treatment parameters through a streamlined number of experiments. Results revealed that a better comprehensive mechanical performance could be obtained under the following combination of heat treatment parameters: quenching temperature of 850 °C, holding time of 35 min, medium of 12% polyalkylene glycol (PAG) aqueous solution, tempering temperature of 460 °C, and holding time of 60 min. As one of the most important testing criteria, fatigue performance would be improved with increasing strength. Additionally, a high ratio of martensite to ferrite is proven to improve the fatigue limit more significantly. After this heat treatment process, the metallographic microstructure and mechanical properties satisfy the technical requirements for the high-speed railway practical operation. These findings provide a valuable reference for the practical forming process of spring fasteners.

The carbon market relies on market-oriented financial means to solve the problem of carbon emissions. An effective carbon pricing mechanism can improve market efficiency and better serve the implementation of carbon emission reduction. The limited attention of investors increases the uncertainty of carbon market volatility and is an important exogenous factor affecting the price of carbon assets. This study innovatively mines keywords of investor attention on the carbon market through online news texts and eliminates those that have no causal link to carbon price forecasting in order to reduce noise. The results show that the keyword extraction method based on news text mining is better than that of nontext mining. Meanwhile, a carbon price forecasting model based on a particle-swarm-optimization LSTM model structure is constructed, and the forecasting accuracy is improved. The results show that carbon market investors pay more attention to carbon quota supply and demand, carbon prices, environmental change, and the energy market. The results have important implications for the development of effective carbon market policies and risk management.

The uncertainty of cyclists’ movements has a significant impact on predicting the risk of collisions between cyclists and vehicles. The purpose of this study was to provide a method for assessing collision risk using probability, taking into account the uncertainty of cyclists’ movements. A cyclist model was first developed using a first-order Markov model. Then, based on Monte Carlo sampling, the distribution characteristics of the minimum distance and the time-to-collision (TTC) between the vehicle and the cyclist were extracted. By fitting these features, the probability density functions of the collision distance and TTC were estimated to derive the collision probabilities. The effectiveness of the collision probability prediction model was benchmarked against a deterministic crash risk prediction model (autonomous emergency braking [AEB] system) applied to three real-world cases previously reconstructed in an in-depth crash database. The results show that the collision probability prediction model can effectively predict the risk of collisions between cyclists and vehicles with better accuracy than AEB systems using a fixed trigger threshold. This study is a valuable reference for the development of advanced vehicle collision avoidance systems to protect cyclists and other vulnerable road users.

Intermediate roll shifting (IRS) is widely used for improving the strip shape in the six-high tandem cold mill, but most related studies are limited to a single stand. To fill the knowledge gap, a three-dimensional (3D) multi-stand elastic–plastic finite element (FE) model was developed for a continuously variable crown (CVC)-6 tandem cold mill using data transfer, which was then validated by industrial experimental results. Based on this FE model, the effects of the IRS on the strip crown, strip flatness, loaded roll gap profile and contact normal stress between rolls at each stand were quantitatively analysed. The results show that from Stand 1 (S1) to Stand 5 (S5), the regulation ability of the IRS on the strip crown shows a decreasing trend, which depends on the strip plastic rigidity; in contrast, the regulation ability on the quadratic flatness experiences an obvious increase from S1 to Stand 4 (S4), then a drop at S5, while the IRS exerts little effect on the quartic flatness and quartic crown of the loaded roll gap. Moreover, the most uniform distribution of contact normal stress emerges at different IRSs from S1 to S5. These findings can contribute to a better understanding of the role of the IRS in controlling the strip shape during tandem cold rolling (TCR).

Skull fracture and brain injury are frequent head injuries in electric two-wheeler (ETW) accidents, and the type of helmet and impact conditions affect the effectiveness of the helmet in protecting the rider's head. The purpose of this study was to conduct in-depth reconstructions of rider's head-to-ground impacts in ten ETW accidents by using a multi-body system combined with a finite element approach and to evaluate the effect of two typical full-face helmets (FFH) and one half-coverage helmet (HCH) through head accelerations and intracranial biomechanics injury metrics in ground impacts. The results showed that all three helmets reduced the risk of skull fracture in most cases, however, FFH performed better due to its wider protection area. In addition, three helmets showed varying degrees of overall reduction in measuring all indicators of brain injury. Although the effectiveness of the helmets on angular acceleration was largely influenced by the angle and location of impact, it was certain that wearing an FFH was more likely to reduce rotational head movements than an HCH, and that the FFH also offered the better advantage in reducing diffuse axonal injury (DAI) risk due to its better resistance to ejection in a crash.

In traffic accidents, multiple head injury types often occur simultaneously and cause severe brain injury for vulnerable road users (VRUs). In this study, a head-weighted injury criterion was developed to assess the risk of severe brain injury considering various injury types. Firstly, 50 in-depth accidents were reconstructed using a high-precision reconstruction method to reconstruct the overall kinematic response and head injury severity of VRUs and analyze the correlation between various head injury criteria and severe brain injury. Then, four injury criteria were selected that correlated well with severe brain injury, namely HIC15, angular acceleration, coup pressure, and maximum principal strain (MPS). Finally, weighted head injury criteria (WIC4) of severe injuries were established based on the four selected injury criteria, and the correlation between WIC4 and severe brain injury was validated based on the area under of receiver operating characteristic curve (AUROC) and the reconstructed results of another 10 selected accidents. The results showed that WIC4 had a good predictive capability for both severe and non-severe brain injury cases, and the AUROC was 0.983, which was significantly higher than that of the single head injury criterion. This study further improved the correlation between head injury criteria and severe brain injury.

To improve the quality of products produced from microforming, various nanolubricants have been applied in the field of micromanufacturing in recent years. In this paper, the effects of glycerol-based lubricant containing TiO2 NPs (NPs) on micro deep drawing (MDD) of austenitic stainless steel (ASS) SUS301 were studied, and the lubrication mechanism involved was discussed. The MDD experiments were conducted with the SUS301 foils under dry, 1, 2, and 4 wt% TiO2 NP lubrication conditions. The results show that the use of the TiO2 nanolubricants can significantly improve the quality of the drawn cups in terms of decreased wrinkling and surface roughness. Besides, the concentration of TiO2 NPs influences lubricity by reducing friction during the MDD process. The peak drawing force is the lowest when 2 wt% nanolubricant is applied, which drops to 72.54 N from 77.38 N under dry conditions. The micro cup drawn under 2 wt% TiO2 nanolubricant has the best quality among those obtained under all the lubrication conditions. The lubrication mechanisms are derived from the mending effects of TiO2 NPs and the formation of thin lubricant films associated with the open lubricant pockets (OLPs) and close lubricant pocket (CLPs) theory in the MDD. The CLPs function as reservoirs that retain lubricants to counteract the load pressure, whereas the OLPs lead to lubricant leakage due to the higher flow resistance. It was found that the lubricant film and NPs are insufficient at a low concentration (1 wt%), while the lubrication performance can be enhanced with increased NP concentration. However, there exist apparent agglomerations on the surface of the produced micro cup when using 4 wt% nanolubricant, which greatly deteriorates the lubricant performance in the MDD process. It is concluded that the lubricant containing 2 wt% TiO2 NPs demonstrates the best lubrication performance during the MDD of ASS SUS301.

The separation of SiC and Si3N4 inclusions from solar cell Si scraps to the slag phase during slag refining is essential to the recovery and production of high-purity Si. This study characterized the SiC and Si3N4 inclusions in solar cell Si scraps, which formed large clusters with complex shapes. According to the experimental and theoretical investigations, the inclusions with large diameters were found to be conducive to passing through the Si/slag interface and then being retained in the slag phase. The favorable conditions such as positive overall wettability, high operating temperature, low viscosity slag, and prolonged-time can promote the small inclusion removal from molten Si scraps.

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) continue to be major concerns for morbidity and mortality, especially in patients treated in the intensive care unit. With the rise in multidrug-resistant organisms, HAP and VAP treatment is challenged by the need for early appropriate treatment, with broad-spectrum agents, while still being aware of the principles of antibiotic stewardship. The two major society guidelines proposed a series of risk factors in their most recent guidelines to help identify patients who can most benefit from narrow- or broad-spectrum initial empiric antibiotic therapy. The guidelines reveal differences in the proposed risk factors and treatment approaches, as well as major similarities.

A series of highly dispersed and c-axis-penetrated mesoporous MWW oligolayers with enhanced properties was prepared via an efficient, green, and controllable method through H2O2-induced micro-explosion.

Silicon was recovered from solar cell Si scraps through 42.5 mol% SiO2–42.5 mol% CaO–15 mol% Al2O3 slag refining. The motion behaviors of Si3N4 and SiC were observed in situ and real-time using a high-temperature laser confocal microscope, and the recovery of Si through slag refining was carried out at 1,500°C for 30 min. Results indicated that both SiC and Si3N4 inclusions were concentrated in the slag, and this work provides a clear framework for recycling and reusing solar cell Si scraps.

The differential diagnosis of renal tumors and abscesses is crucial owing to their different treatments. Although antibacterial administration and radiological examination are excellent means for distinction, misdiagnosis is common and may lead to severe consequences, such as the need for nephrectomy. Here, we report a case involving a 52-year-old Asian woman with a renal mass for which a differential diagnosis was challenging. The mass persisted after administration of intravenous antibiotic therapy for 1 month. A computed tomography scan indicated an inflammatory lesion, whereas magnetic resonance imaging suggested a diagnosis of a tumor. Despite these indications, a right renal abscess was suspected during robot-assisted laparoscopic surgery, and nephron-sparing surgery was performed, which allowed confirmation of the final pathological result by biopsy specimen. Postoperatively, the mass gradually decreased in size after antibiotic therapy for a further month. This case, in which a renal abscess mimicked a tumor and the patient almost underwent a nephrectomy, highlights the need for caution in establishing therapeutic schedules for patients with inaccurate diagnoses. The management strategies for such patients must be reviewed and improved.

Extensive studies have been conducted on the effect of roll bending on strip shape in tandem hot rolling (THR). However, most of them are limited to a single stand. In this study, a three-dimensional (3D) multi-pass elastic–plastic thermal–mechanical finite element (EPTMFE) model for the THR was developed using data transfer technologies and validated by industrial trials. The effects of work roll bending (WRB) on the strip crown, deflection and flattening deformation of work roll (WR) were quantitatively studied employing the developed finite element (FE) model. The results show that with an increase in WRB, the crown of relative deflection difference (RDD) decreases quickly, while the crown of relative flattening deformation difference (RFD) increases slowly; consequently, the strip crown shows a decreasing trend. This suggests that the deflection and flattening deformation of WR influence the strip crown simultaneously, but the former plays a decisive role. In addition, the influence efficiency of WRB on the crown of RFD increases from 0.0077[Formula: see text][Formula: see text]m/kN at [Formula: see text]1 to 0.345 [Formula: see text][Formula: see text]m/kN at [Formula: see text]7, which is dependent on the deformation resistance of the strip. These findings can contribute to a deeper understanding of the influence mechanism of WRB on the strip crown in the THR.

The aim of this study was to examine the effects of emergency avoidance behaviors on the kinematics and injuries of electric two-wheeler (ETW) riders. Four typical riding postures of ETW riders before collisions, including one normal posture and three avoidance postures, were identified through analysis of 298 videos of vehicle to ETW accidents. Crash simulations were then performed using the Total Human Model of Safety (THUMS) occupant model, ETW and a sedan finite element (FE) model, and the kinematics of ETW riders were compared. The risk of head injury and lower extremity injury was also investigated. When the struck foot position of the ETW rider was lower than the ETW pedal, the lower extremity was struck by the sedan bumper and ETW frame from the right and left side respectively, and the upper body of the rider rotated around the hood leading edge. At a car velocity of 40 km/h, the rider was at high risk of head injury and the tibia was fractured. The medial cruciate ligament (MCL) was ruptured in both the 20 km/h and 40 km/h collisions. When the struck foot position of the ETW rider was higher than the pedal, the lower extremity was hit by the bumper and then rebounded. In this situation, the bending moments of the femur and tibia, as well as the bending angle and shear displacement of the knee joint were less than the injury threshold in all crash simulations. Furthermore, when the head was turned toward the colliding car, the risk of head injury varied with the emergency avoidance posture. The height of the struck foot relative to the ETW pedal influenced the rider’s global kinematics, and head and lower extremity injuries risk. In the struck side foot landing and both feet landing postures, the lower extremity was restrained and compressed by the ETW frame, resulting in a high risk of tibia fracture and MCL rupture. Reducing the impact velocities could effectively mitigate the injury risk of the ETW riders; however, loading patterns remain an important factor influencing the risk of lower extremity injury.

This study aimed to report the three-dimensional reconstruction of the foramen ovale (FO) based on computed tomography angiography and describe its shape and related angles. A retrospective analysis of 199 adult patients who were hospitalised at the Department of Neurosurgery, The Second Affiliated Hospital of Bengbu Medical College, Bengbu, China, from January to December 2020 was conducted. The original DICOM files of patients' computed tomography scans were processed by 3D Slicer software to reconstruct the three-dimensional skull. The morphological characteristics of the FO on both sides were analysed. Their size, related angles and volumes, and the differences between the two sides and gender were compared. A total of 398 FO from 199 patients were studied. The most frequent shape of the FO was oval, accounting for 54.27%. The mean lengths of the right and the left sides were 5.40±1.51 and 5.10±1.18mm, respectively. The mean width on the right and left sides was 3.23±1.16 and 3.33±1.19 mm, respectively. The FO is most commonly oval in shape. Clinicians may use the anatomical characteristics regarding the size and shape of the FO for diagnosis and treatment. Key Words: Foramen ovale, Computed tomographic angiography, 3-Dimensional anatomy.

In this article, an improved pulsewidth modulation (PWM) strategy is introduced for three-level active neutral point clamped converters based on a hybrid configuration of silicon carbide (SiC) mosfets and silicon (Si) insulated gate bipolar transistor (IGBTs). Compared with the conventional PWM strategies in the literature, this proposed PWM strategy enables the SiC switches only to interface with small commutation loops, thus the turn- off voltage overshoots caused by the parasitic loop inductance and high $\boldsymbol{di}/\boldsymbol{dt}$ are much lower. Soft switching is achieved across all the IGBTs, and the switching losses of the converter only dissipate from the SiC mosfets , leading to high efficiency of the converter. Also, with this improved PWM strategy, the conduction loss at zero voltage output of this converter is reduced due to the turn- on of two parallel conduction paths. Furthermore, this proposed PWM strategy can protect the body diodes of the SiC mosfets from conducting large load current. All these advantages with the proposed PWM strategy are experimentally verified in a megawatt-scale three-phase three-level “SiC+Si” hybrid active neutral point clamped inverter developed for electric aircraft propulsion applications.

Communication and adoption of modern study design and analytical techniques is of high importance for the improvement of clinical research from observational data.To compare a modern method for statistical inference, including a target trial emulation framework and doubly robust estimation, with approaches common in the clinical literature, such as Cox proportional hazards models.This retrospective cohort study used longitudinal electronic health record data for outcomes at 28-days from time of hospitalization within a multicenter New York, New York, hospital system. Participants included adult patients hospitalized between March 1 and May 15, 2020, with COVID-19 and not receiving corticosteroids for chronic use. Data were analyzed from October 2021 to March 2022.Corticosteroid exposure was defined as more than 0.5 mg/kg methylprednisolone equivalent in a 24-hour period. For target trial emulation, exposures were corticosteroids for 6 days if and when a patient met criteria for severe hypoxia vs no corticosteroids. For approaches common in clinical literature, treatment definitions used for variables in Cox regression models varied by study design (no time frame, 1 day, and 5 days from time of severe hypoxia).The main outcome was 28-day mortality from time of hospitalization. The association of corticosteroids with mortality for patients with moderate to severe COVID-19 was assessed using the World Health Organization (WHO) meta-analysis of corticosteroid randomized clinical trials as a benchmark.A total of 3298 patients (median [IQR] age, 65 [53-77] years; 1970 [60%] men) were assessed, including 423 patients who received corticosteroids at any point during hospitalization and 699 patients who died within 28 days of hospitalization. Target trial emulation analysis found corticosteroids were associated with a reduced 28-day mortality rate, from 32.2%; (95% CI, 30.9%-33.5%) to 25.7% (95% CI, 24.5%-26.9%). This estimate is qualitatively identical to the WHO meta-analysis odds ratio of 0.66 (95% CI, 0.53-0.82). Hazard ratios using methods comparable with current corticosteroid research range in size and direction, from 0.50 (95% CI, 0.41-0.62) to 1.08 (95% CI, 0.80-1.47).These findings suggest that clinical research based on observational data can be used to estimate findings similar to those from randomized clinical trials; however, the correctness of these estimates requires designing the study and analyzing the data based on principles that are different from the current standard in clinical research.

ImportanceCommunication and adoption of modern study design and analytical techniques is of high importance for the improvement of clinical research from observational data.ObjectiveTo compare (1) a modern method for causal inference including a target trial emulation framework and doubly robust estimation to (2) approaches common in the clinical literature such as Cox proportional hazards models. To do this, we estimate the effect of corticosteroids on mortality for moderate-to-severe coronavirus disease 2019 (COVID-19) patients. We use the World Health Organization’s (WHO) meta-analysis of corticosteroid randomized controlled trials (RCTs) as a benchmark.DesignRetrospective cohort study using longitudinal electronic health record data for 28 days from time of hospitalization.SettingsMulti-center New York City hospital system.ParticipantsAdult patients hospitalized between March 1-May 15, 2020 with COVID-19 and not on corticosteroids for chronic use.InterventionCorticosteroid exposure defined as >0.5mg/kg methylprednisolone equivalent in a 24-hour period. For target trial emulation, interventions are (1) corticosteroids for six days if and when patient meets criteria for severe hypoxia and (2) no corticosteroids. For approaches common in clinical literature, treatment definitions used for variables in Cox regression models vary by study design (no time frame, one-, and five-days from time of severe hypoxia).Main outcome28-day mortality from time of hospitalization.Results3,298 patients (median age 65 (IQR 53-77), 60% male). 423 receive corticosteroids at any point during hospitalization, 699 die within 28 days of hospitalization. Target trial emulation estimates corticosteroids to reduce 28-day mortality from 32.2% (95% CI 30.9-33.5) to 25.7% (24.5-26.9). This estimate is qualitatively identical to the WHO’s RCT meta-analysis odds ratio of 0.66 (0.53-0.82)). Hazard ratios using methods comparable to current corticosteroid research range in size and direction from 0.50 (0.41-0.62) to 1.08 (0.80-1.47).Conclusion and RelevanceClinical research based on observational data can unveil true causal relationships; however, the correctness of these effect estimates requires designing the study and analyzing the data based on principles which are different from the current standard in clinical research.Key PointsQuestionHow do modern methods for causal inference compare to approaches common in the clinical literature when estimating the effect of corticosteroids on mortality for moderate-to-severe coronavirus disease 2019 (COVID-19) patients?FindingsIn an analysis using retrospective data for 3,298 hospitalized COVID-19 patients, target trial emulation using a doubly robust estimation procedure successfully recovers a randomized controlled trial (RCT) meta-analysis benchmark. In contrast, analytic approaches common in the clinical research literature generally cannot recover the benchmark.MeaningClinical research based on observational data can unveil true causal relations. However, the correctness of these effect estimates requires designing and analyzing the data based on principles which are different from the current standard in clinical research. Widespread communication and adoption of these analytical techniques are of high importance for the improvement of clinical research.

SUMMARY STATEMENT Simulation played a critical role in our institution's response to the COVID-19 pandemic in New York City. With the rapid influx of critically ill patients, resource limitations, and presented safety concerns, simulation became a vital tool that provided solutions to the many challenges we faced. In this article, we describe how simulation training was deployed at our institution throughout the course of the pandemic, which included the period of our medical surge. Simulation helped refine protocols, facilitate practice changes, uncover safety gaps, and train redeployed healthcare workers in unfamiliar roles. We also discuss the obstacles we encountered with implementing simulations during the pandemic, the measures we took to adapt to our limitations, and the simulation strategies and end products that were derived from these adaptations.

Introduction The treatment of intestinal perforation caused by the SBC enters the small intestine in elderly patients is a challenge for urologists. The report is to share our experience of conservative treatment after a 90-year-old male with the suprapubic bladder catheter enters the small intestine. Presentation of case Because of the device was obstructed, a 90-year-old male went to our hospital with his family and requested to replace the SBC. When the fistula tube was replaced, it entered the intestine through the intestinal injury site instead of entering the bladder. During the hospitalization, the patient was given supportive treatments and the SBC was dynamically monitored daily and it was intermittently withdrawn out during this period. After the drainage volume was less than 10 mL for three consecutive days and the intestinal fistula was healing gradually, the catheter was taken out. Discussion According to our experience, the common complications in the process include failure to pull out the SBC, abnormal position of the SBC, and poor drainage of the SBC. However, the drainage tube placing into the small intestine through the original hole of the suprapubic bladder fistula during the replacement process is quite rare. When elderly patients have traumatic small bowel perforation, the diagnosis and treatment of intestinal perforation in elderly patients was particularly important. Conclusion The conservative treatment of intestinal perforation is suitable for elderly patients who are unsuitable or unwilling to undergo a surgical operation. Of course, it should be in accordance with the patient's condition to make the right choice of treatment.

High-power-density high-speed electric motors for aircraft hybrid-electric propulsion (HEP) applications require high fundamental output frequency from power inverters. Conventional silicon (Si)-based megawatt (MW)-scale power inverters typically have low switching frequency that is not sufficient to meet the dynamic and harmonic requirements for such applications. An MW-scale medium-voltage three-level active neutral-point-clamped (ANPC) inverter based on a hybrid utilization of silicon carbide (SiC) and Si power devices (i.e., “SiC+Si”) has been developed for high-speed HEP drive applications, which has a rated output frequency of 1.4 kHz at 1-MW active power. To evaluate the power capability and efficiency of this ANPC inverter in the laboratory, power pump-back tests need to be carried out. In this article, control methods for single- and three-phase inverter pump-back tests have been developed to evaluate the performance of such high-frequency propulsion drives. The implementation and experimental results are presented to verify the efficacy of the control methods and the performance of the MW-scale “SiC+Si” ANPC inverters.

A gliding arc plasma source designed for high efficient ignition has been studied with the help of numerical simulation and experiments. A coupled 3D–0D approach has been proposed to model the gliding arc from ignition (the equilibrium stage) to extinguish (the non–equilibrium stage). The model takes the measured discharge morphology, voltage, current, and velocity as inputs, and has been validated by comparing the calculated temperature with experimental results from an independent group. The temporal evolution of the temperature as well as active species, and the effective penetration length of the gliding arc has been studied; the influence of the gliding arc-based plasma igniter on the ignition delay time of a premixed pentane-air gas has also been theoretically analyzed.

Controllable liquid transportation is of great value in various practical applications. Here, we experimentally demonstrate a method of actuating high-speed droplet transport with large manipulation controllability on lubricated surfaces using a corona discharge generated by a simple needle-plate electrode configuration. Linear motion of droplets is realized with a maximum velocity of 30 mm/s. Factors affecting the velocity of these droplets are analyzed systematically, and the mechanism of droplet transport is explained. The lubrication film flow induced by charge deposition is shown to be the dominating factor in the droplet manipulation controllability. The new method presented here opens a new path of high-performance manipulation of liquid droplets by controlling the lubrication liquid film flow with charge deposition.

This study proposed a strategy for the production of lactide from biomass-derived carbohydrate with excellent yield, involving sugar to racemic lactic acid conversion over Sn-containing Beta zeolite and racemic lactic acid to lactide conversion over H-Beta zeolite. Structural characteristics of the resulting lactide and extensive applicability for various substrates are also presented.

α2-Adrenegic receptors (α2Rs) are important presynaptic modulators of central noradrenergic function (auto receptors) and postsynaptic mediators of many of the widespread effects of catecholamines and related drugs. Studies have shown that ruminants (such as goats and cattle) express special α2DR subtypes in addition to α2BR and α2CR. Real-time quantitative PCR and Western blotting were used to investigate the distribution and density of α2R in different nuclei of the goat central nervous system, selected regions of the spinal cord (L4-L6), and in various peripheral tissues. α2-AR subtype-specific antibodies were injected intrathecally and intracerebroventricularly into the tested goats to block the corresponding subtype of receptors. Pain threshold and physiological parameters were evaluated to explore the functional characteristics of α2BR, α2CR and α2DR in goats. Our results suggest that the expression of the mRNAs and proteins of all three α2R subtypes are widely but unevenly distributed in the goat CNS and peripheral tissues. Furthermore, α2DR plays a more important role in α2R-mediated analgesia in goats than α2BR and α2CR, whereas α2CR activation exerts a greater effect on body temperature than α2BR and α2DR.

A new kavalactone, 4'-hydroxyl dihydro-5, 6-dehydrokavain (

Drug resistance is a crucial obstacle to achieve satisfactory chemotherapeutic effects. Numerous studies have shown that the PI3K/Akt signaling pathway plays a significant role in various processes of cellular events and tumor progression, while few studies have focused on the PI3K/Akt signaling pathway in drug resistance of endothelial cells. The present study aims to explore the relationship of PI3K/Akt signaling and cellular resistance to anticancer drugs in human microvessel endothelial cells (HMEC-1). We established stable sunitinib-resiatant human microvessel endothelial cells (HMEC-su) after long-term exposure to sunitinib (a small-molecule tyrosine kinase receptor inhibitor) for 12 months. HMEC-su showed significant alternations of cell morphology and exhibited a 2.32-fold higher IC50 of sunitinib than parental HMEC-1 cells. Expression of P-glycoprotein (P-gp) and breast cancer-resistance protein (ABCG2) which mediates drug efflux, increased significantly in HMEC-su lines compared with HMEC-1 cells by western blots assay. Our study further demonstrates that LY294002 (blocking the PI3K/Akt pathway) enhances the sensibility of HMEC-su to suntinib and inhibits the gene transcription and protein expression of P-gp, ABCG2 in HMEC-su cells. In conclusion, these results indicate that LY294002 could reverse P-gp and ABCG2 mediated-drug resistance to sunitinib in HMEC-su cells by inhibiting PI3K/Akt signaling.

Induced pluripotent stem cells (iPSCs) have become an essential research platform to study different human diseases once being discovered by Dr. Shinya Yamanaka in 2006. Another breakthrough in biomedical research is the application of CRISPR/Cas9 system for genome editing in mammalian cells. Although numerous studies have been done to develop methods for gene editing in iPSCs, the current approaches suffer from several limitations, including time and labor consuming, low editing efficiency, and potential off-target effects. In the current study, we report an electroporation-mediated plasmid CRISPR/Cas9 delivery approach for genome editing in iPSCs. With this approach, an edited iPSC cell line could be obtained within 2 weeks. In addition, the transit introducing of CRISPR/Cas9 machinery could minimize genomic integration of Cas9 gene, which avoided potential long-term side effects of Cas9 enzyme. We showed that CRISPR/Cas9-mediated genomic editing did not affect pluripotency and differentiation ability of iPSCs. With the quickly evolving of both iPSC and CRISPR/Cas9-mediated genome editing research fields, we believe that our method can significantly facilitate the application of genome editing in iPSCs research.

The objective of this study was to investigate the effect of a striking vehicle steering maneuvers on the kinematics and head injury risk of cyclists using the finite element (FE) modeling method. ...

Ara h 1 is recognized as a major peanut allergen. The effects of high hydrostatic pressure (HHP) on the immunoreactivity and structure of Ara h 1 were investigated in this study. The immunoreactivity of Ara h 1 was considerably reduced (P

A hybrid-electric propulsion system is an enabling technology to make the aircraft more fuel saving, quieter, and lower carbide emission. In this article, a megawatt (MW) scale power inverter based on a three-level active neutral-point-clamped (3L-ANPC) topology will be developed. To achieve high efficiency, the switching devices operating at carrier frequency in the power converter are configured by the emerging silicon carbide (SiC) metal–oxide–semiconductor field-effect transistors, while the conventional silicon (Si) insulated-gate bipolar transistors are selected for switches operating at the fundamental output frequency. To obtain high power density, dc bus voltage is increased from the conventional 270 V to medium voltage of 2.4 kV to reduce cable weight. Also, unlike the traditional 400 Hz dominated aircraft ac systems, the rated fundamental output frequency here is boosted to 1.4 kHz to drive the high-speed motor, which helps further to reduce the motor weight. Main hardware development and control modulation strategies are presented. Experimental results are presented to verify the performance of this MW-scale medium-voltage “SiC+Si” hybrid 3L-ANPC inverter. It is shown that the 1-MW 3L-ANPC inverter can achieve a high efficiency of 99% and a high power density of 12 kVA/kg.

This study aimed to revise and validate a Chinese Version of the Acquired Capability for Suicide Scale (ACSS-CV). In study 1 of 395 Chinese college students, a two-factor model comprising fearlessness about death and pain tolerance achieved satisfactory model fit. In study 2 of 491 different students, the ACSS-CV had good internal consistency, test-retest reliability, convergent validity, and discriminant validity. The ACSS-CV may be considered a useful instrument for measuring the acquired capability for suicide in Chinese college students.

The effects of Al and Sc on mechanical properties of FeCoNi multi-element alloys (MEAs) were investigated by compressive tests. The microstructures of FeCoNi MEAs with different contents of Al and Sc were characterized and the strengthening mechanisms were discussed. The results show that FeCoNi MEA with a low content of Al has a face-centered cubic (FCC) structure. The yield strength increases linearly with the increase of Al content, which is largely caused by solid solution hardening. Further addition of Sc can promote the formation of a new phase in (FeCoNi)1−xAlx MEAs. A minor addition of Sc can significantly increase the yield strengths of (FeCoNi)1−xAlx MEAs with a low Al content and improve the compressive plasticity of (FeCoNi)1−xAlx MEAs with a high Al content.

α2-Adrenegic receptors (α2Rs) are important presynaptic modulators of central noradrenergic function (auto receptors) and postsynaptic mediators of many of the widespread effects of catecholamines and related drugs. Studies have shown that ruminants (such as goats and cattle) express special α2DR subtypes in addition to α2BR and α2CR. Real-time quantitative PCR and Western blotting were used to investigate the distribution and density of α2R in different nuclei of the goat central nervous system, selected regions of the spinal cord (L4-L6), and in various peripheral tissues. α2-AR subtype-specific antibodies were injected intrathecally and intracerebroventricularly into the tested goats to block the corresponding subtype of receptors. Pain threshold and physiological parameters were evaluated to explore the functional characteristics of α2BR, α2CR and α2DR in goats. Our results suggest that the expression of the mRNAs and proteins of all three α2R subtypes are widely but unevenly distributed in the goat CNS and peripheral tissues. Furthermore, α2DR plays a more important role in α2R-mediated analgesia in goats than α2BR and α2CR, whereas α2CR activation exerts a greater effect on body temperature than α2BR and α2DR.

Objective To determine whether surge conditions were associated with increased mortality. Design Multicenter cohort study. Setting U.S. ICUs participating in STOP-COVID. Patients Consecutive adults with COVID-19 admitted to participating ICUs between March 4 and July 1, 2020. Interventions None Measurements and Main Results The main outcome was 28-day in-hospital mortality. To assess the association between admission to an ICU during a surge period and mortality, we used two different strategies: (1) an inverse probability weighted difference-in-differences model limited to appropriately matched surge and non-surge patients and (2) a meta-regression of 50 multivariable difference-in-differences models (each based on sets of randomly matched surge- and non-surge hospitals). In the first analysis, we considered a single surge period for the cohort (March 23 – May 6). In the second, each surge hospital had its own surge period (which was compared to the same time periods in matched non-surge hospitals). Our cohort consisted of 4342 ICU patients (average age 60.8 [sd 14.8], 63.5% men) in 53 U.S. hospitals. Of these, 13 hospitals encountered surge conditions. In analysis 1, the increase in mortality seen during surge was not statistically significant (odds ratio [95% CI]: 1.30 [0.47-3.58], p = .6). In analysis 2, surge was associated with an increased odds of death (odds ratio 1.39 [95% CI, 1.34-1.43], p Conclusions Admission to an ICU with COVID-19 in a hospital that is experiencing surge conditions may be associated with an increased odds of death. Given the high incidence of COVID-19, such increases would translate into substantial excess mortality.

Background Currently, there are relatively few studies on the effects of changes in oestrogen and androgen levels on prostatic microvessel density (MVD). This article aimed to study the changes in prostatic MVD in Sprague-Dawley (SD) rats after castration under the effect of oestrogen/androgen at different concentrations. Methods Male SD rats aged 3–4 months were randomly divided into a control group, a castration group, and groups with different concentrations of oestrogen/androgen treatment after castration. Dihydrotestosterone (DHT) and oestradiol (E) were administered daily by subcutaneous injection for one month. All the rats were killed by cervical dislocation after one month, and the serum DHT and E concentrations of the rats in each group were measured by ELISA. Prostate tissue specimens were immunohistochemically stained with monoclonal antibodies against CD34 and factor VIII for MVD. Results Compared with the control group, the MVD decreased significantly in the castration group (P P P Conclusions Androgens play an important role in the regulation of prostatic MVD in SD rats, and a decrease in DHT concentration can induce a decrease in prostatic MVD. In contrast, prostatic MVD can be increased with increasing DHT concentration. In addition, prostatic MVD can be increased gradually with increasing oestrogen concentration.

To investigate the efficacy and safety of percutaneous micro-balloon compression (PBC) assisted by Dyna-CT-based image fusion technique in the treatment of trigeminal neuralgia (TN). This study is the retrospective analysis of the efficacy and safety of 18 patients with TN treated by PBC assisted with Dyna-CT-based image fusion technique from May 2020 to May 2021. The puncture route from the skin to the foramen ovale（FO）was reconstructed after Dyna-CT scanning; and the puncture direction was adjusted according to the virtual puncture route until the puncture was completed. Dyna-CT-assisted puncture was successful in all 18 patients. The puncture was accurate and effectively shortened the operation time. Importantly, pain was relieved in all patients, and no puncture-related complications occurred. Dyna-CT-based image fusion real-time-assisted PBC for the treatment of TN is safe and effective, making the operation easier and faster, greatly improving the success rate of the puncture, and reducing the risk of operation-related complications. Key Words: Dyna-CT, Percutaneous micro-balloon compression, Trigeminal neuralgia.

BackgroundThe ability to regenerate lost or damaged body parts is an ancient animal characteristic with a wide yet variable distribution across all phyla. Sponges, likely the sister group to all other animals, have remarkable regenerative abilities including whole body regeneration and re-development from dissociated cells. The calcareous sponge Sycon ciliatum has been subject to various regeneration studies since the beginning of the last century. However, the early steps of wound healing of S. ciliatum have not been addressed from the molecular perspective.ResultsIn this study, we combined electron microscopy with gene expression analysis to investigate wound healing after transverse sectioning of S. ciliatum. Microscopic analysis revealed massive transdifferentiation and collective migration behaviour of choanocytes and pinacocytes early upon injury (6-12h) as the main mechanisms for quick closure of the wound surface. RNA-sequencing identified upregulation of components of the conserved metazoan Wnt and TGFβ signalling pathways within 3h, preceding morphologically detectable wound healing events. De novo upregulation after a decline in expression coincides with morphologically visible polarity establishment. Moreover, by integrating the new wound healing data set with previously published data derived from intact sponge, we demonstrate similarity between gene activity during early wound healing and osculum maintenance. Whole mount in situ hybridisation of the TGFβ signalling pathway ligand SciTGFβU and signal transducer SciSmadRa show that the early activation of both is initially encompassing a large area surrounding the cut surface with gradual restriction to the edge of the forming regenerative membrane as wound healing progresses. While SciTGFβU transcripts are localised to exo- and endopinacocytes, SciSmadRa expression appears across all cell types. Using an EdU cell proliferation assay, we found that a global increase in cell proliferation is not visible before 12h into wound healing. Hence, the initial stages to cover the injury site including cell transdifferentiation and migration seem to be executed by cells remaining after injury. Gene expression clustering coupled with GO term enrichment analysis confirmed that expression of genes involved in processes related to cell proliferation, DNA repair as well as apoptotic processes at 3 and 6h of wound healing was not upregulated. On the other hand, genes associated with positive regulation of transcription, signal transduction, actin filament and chromatin organisation, as well as the Wnt signalling pathway are upregulated at early wound healing stages.ConclusionWe have analysed wound healing in the calcareous sponge Sycon ciliatum using microscopic and genomic methods. This study highlights a remarkable mechanism of interplay between cell transdifferentiation and collective migration we hypothesise to be regulated by conserved metazoan developmental pathways and numerous taxonomically restricted genes. Expression of these genes in regenerating and intact sponges sheds light on the long-standing question whether embryonic developmental pathways are redeployed in regeneration.

PurposeTo evaluate the association between body mass index (BMI) and clinical outcomes other than death in patients hospitalised and intubated with COVID-19.MethodsThis is a single-centre cohort study of adults with COVID-19 admitted to New York Presbyterian Hospital-Weill Cornell Medicine from 3 March 2020 through 15 May 2020. Baseline and outcome variables, as well as lab and ventilatory parameters, were generated for the admitted and intubated cohorts after stratifying by BMI category. Linear regression models were used for continuous, and logistic regression models were used for categorical outcomes.ResultsThe study included 1337 admitted patients with a subset of 407 intubated patients. Among admitted patients, hospital length of stay (LOS) and home discharge was not significantly different across BMI categories independent of demographic characteristics and comorbidities. In the intubated cohort, there was no difference in in-hospital events and treatments, including renal replacement therapy, neuromuscular blockade and prone positioning. Ventilatory ratio was higher with increasing BMI on days 1, 3 and 7. There was no significant difference in ventilator free days (VFD) at 28 or 60 days, need for tracheostomy, hospital LOS, and discharge disposition based on BMI in the intubated cohort after adjustment.ConclusionsIn our COVID-19 population, there was no association between obesity and morbidity outcomes, such as hospital LOS, home discharge or VFD. Further research is needed to clarify the mechanisms underlying the reported effects of BMI on outcomes, which may be population dependent.

The synergistic effect of electrostatically enhanced fibrous filtration originates from the charging characteristics of aerosol particles and electret fibers in an electric field. Two electrostatically enhanced fibrous filter systems are designed in this study to investigate the mechanism of the effects of the charging characteristics of oily aerosol on the filtration efficiency. We investigate the charging characteristics and their effects on the filtration efficiency of dioctyl-phthalate (DOP) aerosol particles of various sizes by setting different filter systems and electric field intensities. The experimental results show that the charge of DOP particles increases with the strength of the electric field, and the average charge increases with the particle size. The maximum charge of DOP particles reaches 4760 eC/P, and the filtration efficiency of the coupled system improves when DOP particles are amply charged. For 0.25 μm DOP particles as the most penetrating particle size, the system had good long-term stability, and the filtration efficiency is approximately 72% higher than that of the fiber acting alone. Meanwhile, the problem of oily aerosol deposition reducing the electret filtration efficiency is solved, providing a basis for long-term filtration and oily aerosol purification by electret fiber.