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This paper details the development and verification tests of an open-source code named hy2LPTFoam intended for solving high-speed non-equilibrium gas-particle flows in OpenFOAM. The solver, based on hy2Foam for high-speed non-equilibrium gas flow, integrates multiple particle force models, heat transfer models, the diffusion-based smoothing method, and the MPPIC method. The verification tests incorporate interactions between shock waves and particle curtains with varying particle volume fractions, a JPL nozzle generating a two-phase gas–particle flow, and a Mars entry body with two particle inflow mass fractions. The tests yield good physical agreement with numerical and experimental data from the literature.

Abstract This paper aims at preparing a smart wearable purple ceramic that meet the color requirements of purple smart wear in the market after using zirconate neodymium as a chromogenic agent. However, the mechanical performance of zirconate neodymium purple ceramic is not satisfactory, especially it has an extremely low fracture toughness. To solve this, a 3 mol% yttria-stabilized zirconia (3YSZ) is added to zirconate neodymium in the preparation of multiphase ceramics to improve its mechanical properties. In this experiment, a series of ceramic samples with addition of increasing amount of 3YSZ 0, 20, 40, 50, 60, 70 and 80% were prepared in the 1400–1500 °C sintering temperature range. It was found that at the same temperature, the mechanical properties of the ceramic samples gradually improved with the increase in the 3YSZ content. Moreover, with the same content, the mechanical properties of the ceramic samples gradually improved with the decrease in temperature. The results show that when 3YSZ has a mass fraction of 80% and is sintered at 1400 °C, the fracture toughness of the prepared ceramic samples reaches 8.15 MPa‧m1/2, which is nearly two times higher than that of the monolithic neodymium zirconate 2.57 MPa‧m1/2. The Vickers hardness of the prepared ceramic samples reached 12.93 GPa, which is nearly 88% higher than the undoped neodymium zirconate. This indicates that the samples can be applied in smart wearables, such as mobile phone backplane, with a certain practical significance for engineering toughening of zirconate ceramics.

Coping capacity is a key aspect of driver-vehicle interaction when drivers observe and make decisions, and is of great importance for drivers. However, different drivers have different self-cognition and assess their driving abilities differently, especially for novice drivers. Based on questionnaire data, this study has investigated the coping capacities of drivers in both static environments and dynamic environments. With the ANOVA analysis method and the structural equation model (SEM), this study has verified the effects of gender and driving factors (driving years, driving frequency, driving time) on drivers' coping capacities based on drivers' self-assessment scores and mutual assessment scores. Drivers' self-assessment scores show significant effects of all factors on drivers' coping capacities, and drivers' mutual assessment scores show significant effects of all factors, excluding driving time, on drivers' coping capacities. Also, it has been found that all drivers in the driving year group have cognitive biases. It seems that first-year drivers are always overconfident with their driving skills, while drivers with a driving experience of more than three years usually score driving skills of themselves and other drivers most conservatively. With increased exposure to various traffic conditions, experienced drivers are more aware of their limitations in dealing with complex traffic situations, while novice drivers do not know their lack of capability to properly respond to any unexpected situation they could encounter.

The purpose of this paper is to reveal the effects of porous structure and surface acid-base sites on CO2 adsorption for those nitrogen-doped activated carbons, which were prepared in a tube furnace with anaerobic conditions (TF) and muffle furnace with oxygen-poor conditions (MF), respectively. Subsequently, the porous structure and surface group distribution of the prepared activated carbons TF and MF were characterized in detail through those methods such as scanning electron microscope (SEM), Brunauer-Emmett-Teller (BET), Barret-Joyner-Halenda method (BJH), Horvath-Kawazoe method (HK), Dubinin-Radushkevich method (DR), mercury intrusion porosimetry (MIP), non-local density functional theory method (NLDFT), (in-situ) Fourier transform infrared spectroscopy (FTIR), Raman spectra (RS), X-ray photoelectron spectroscopy (XPS), and temperature programmed desorption (TPD). Then the thermodynamic and kinetic characteristics of CO2 adsorption such as adsorption capacity, selectivity, and activation energy were systematically investigated based on the static volumetric method and dynamic adsorption method. The results showed that the anaerobic or oxygen-poor preparation atmosphere affected the micropore volume and surface functional group distribution of activated carbons. Thus the activated carbon TF exhibited a higher adsorption capacity of CO2 (7.9 mmol g−1, 100 kPa and 273 K) and longer dynamic breakthrough time due to the higher microporosity (Vmic/Vt = 90 %), while the activated carbon MF exhibited the higher selectivity (14.7, CO2/N2 molar ratio of 1:1) and adsorption rate due to the higher nitrogen and oxygen contents (11.23 %, 13.53 %) in the main forms such as pyrrole nitrogen (N-5), carbony, and carboxyl. Overall, CO2 adsorption on the activated carbons was verified to be a dominant physical adsorption and exothermic process, which was suitable to be described by a quasi-first-order dynamic model. Meanwhile, compared with TF, the activated carbon MF exhibited the higher activation energy of CO2 adsorption (12.98 kJ mol−1 for TF and 17.23 kJ mol−1 for MF), accompanied by the larger rate constants (k1) and diffusion coefficients (D). The higher activation energy for MF meant that the adsorption temperature had a stronger effect on the rate constant during CO2 adsorption.

The algorithm for star identification is a crucial technology for determining the orientation of spacecraft using star sensors. Traditional star identification algorithms achieve matching by seeking a unique or a few optimal solutions. However, in high-noise environments, some solutions may be lost, which could result in matching failure. A new lost-in-space architecture algorithm aimed at rapid identification under high star position noise conditions by directly using star positions for final matching is proposed in this paper. The main idea of this algorithm is to construct sufficiently redundant navigation triangles, fully utilizing the physical relationships of the features and forming a screening method from high to low dimensions and from loose to strict. During identification, a multi-layer joint screening matching method is adopted to screen triangles as a whole, narrowing the range of matches quickly while retaining error tolerance. In a series of simulation experiments, this algorithm achieved identification rates of 99.51%, 99.06%, and 98.42% for 2.0 pixel star position noise, 1.0 Mv star magnitude noise, and 5 false stars, respectively. In terms of practical application, all 1000 star images taken by the star sensor in orbit have been successfully identified, and it only takes 28ms to identify each image. In addition, star images taken by consumer-grade cameras from the ground also show that the algorithm has strong robustness to star position noise, magnitude error and false star interference in more severe environments. This method provides partial algorithmic reference for non-specialized design of star sensors for low-cost, large-scale satellites in the future.

In order to reveal the thermodynamic properties of CO2 adsorption on a promising nitrogen-doped biochar under isothermal and isovolumetric conditions, the adsorption isotherms based on 391 data points were experimentally obtained to investigate the mass and energy transfer process during CO2 adsorption by combining with model analysis. Then a series of interesting phenomena were found by analyzing those thermodynamic parameters in the equilibrium and non-equilibrium states. The capacity of CO2 on the biochar non-linearly increases with an increase of the initial pressure and volume-mass ratio but the decrease of the adsorption temperature. It can be up to 7.6 mol/kg at 273 K and 100 kPa. The adsorption system exchanges the energy with the surrounding environment mainly by heat transfer. And the interfacial energy of the adsorbent can be affected by the adsorbate system in three parts: pressure change from gas phase, molecular force from adsorbed phase and heat transfer. Then the conditions with low adsorption temperature, high initial pressure and large volume-mass ratio can provide a strong driving force for CO2 adsorption. These phenomena that have not been reported before will help us get a better technical process for CO2 capture.

Abstract Background In recent years, the safety and effectiveness of one-stage percutaneous nephrolithotomy (PCNL) for the treatment of calculous pyonephrosis have been proven. In order to further reduce postoperative pain and hospital stay, we first proposed and practiced the idea of one-stage tubeless percutaneous nephrolithotomy for calculous pyonephrosis. Methods A retrospective analysis was performed of case data of 30 patients with asymptomatic calculous pyonephrosis treated in our center with one-stage PCNL from January 2016 to January 2021. Patients were routinely given 20 mg of furosemide and 10 mg of dexamethasone sodium phosphate injection intravenously at the beginning of anesthesia. Among them, 27 patients successfully underwent one-stage tubeless percutaneous nephrolithotomy, while 3 cases were given indwelling nephrostomy tubes because of proposed second-stage surgery or the number of channels was greater than or equal to 3. All patients were operated on by the same surgeon. Results Preoperatively, 11 of 30 patients (8 men and 22 women) had positive urine bacterial cultures, and all were given appropriate antibiotics based on drug sensitivity tests. All patients completed the surgery successfully. The mean operative time was 66.6 ± 34.7 min, the mean estimated blood loss was 16.67 ± 14.34 mL and the mean postoperative hospital stay was 5.0 ± 3.1 days. The mean postoperative hospital stay was 4.6 ± 2.5 days among the 27 patients with one-stage tubeless percutaneous nephrolithotomy. Of the 3 patients with postoperative fever, 2 had the tubeless technique applied. One patient with 3 channels was given renal artery interventional embolization for control of postoperative bleeding. None of the 30 patients included in the study developed sepsis. The final stone-free rate was 93.3% (28/30) on repeat computed tomography at 1 month postoperatively. The final stone-free rate was 92.6% in the 27 patients undergoing one-stage tubeless percutaneous nephrolithotomy (25/27). Conclusions One-stage tubeless PCNL is an available and safe option in carefully evaluated and selected calculous pyonephrosis patients.

This work focuses on establishing a kind of extended adsorption model equation including four variables relevant to preparation conditions (activation temperature and heating rate) except adsorption situations (adsorption temperature and adsorption pressure). And the equation is used for thermodynamic analysis of CO2 adsorption on a promising cyclodextrin based porous material. Novelty, those isotherms of CO2 adsorption on the porous materials prepared at different activation temperatures and heating rates are experimentally obtained to investigate the effects of activation temperature and heating rate on CO2 adsorption. Then the parameters of the model equation are quantified based on 589 data points from the isotherms by the least squares regression method combined with the steepest descent mode. Research results indicate that high performance for CO2 uptake appears on the porous material prepared at high activation temperature and low heating rate. Differently with the previous studies, the adsorption site energy distribution is found to exhibit an asymmetrical peak and the peak site energy increases with an increase of activation temperature but the decrease of heating rate. Moreover, a series of interesting phenomena of those thermodynamic state parameters via adsorption temperature and pressure are verified based on both extended Slip model and D-R model, which have not been reported before.

Black zirconia ceramics has many problems, such as uneven color and poor phase stability. The reason for this phenomenon is that the colorant uses a colorant with a complex black spinel structure, and also the application of a dyeing method. To improve the color uniformity and phase stability of black ceramics, TiO2 was introduced to replace the traditional complex black spinel, a high-temperature reduction method (HTR) was employed to prepare a black Ti-doped zirconia ceramic, stead of the conventional dyeing method. After the HTR at 1400 °C, the concentration of Ti3+ and oxygen vacancies increased, and the lightness of the ceramic samples decreased from 93.48 to 44.17. The black ceramic is uniform in color and stable in phase, avoiding the disordered phase of the spinel doped multiphase zirconia ceramic. The results indicate that the overall color of the samples depends on the development mechanism of the color center. The formation of color centers (F+ centers) in this work was related to the electronic transition of Ti 3d states and oxygen vacancies generated during the HTR. F+ centers cause a strong light absorbance over the entire visible light range (400–750 nm), so that the color of the ceramics is black. Based on their good color attributes, black ceramics have great potential in industry, for example as the back plate of mobile phones.

The participation of silent mating type information regulation 2 homolog 1 (SIRT1) in amyotrophic lateral sclerosis (ALS) has been reported in many studies. However, the role of the expression and function of SIRT1 in the hypothalamus in ALS remains unknown. In the current study, we performed western blot, co-immunoprecipitation and immunofluorescence analyses to determine the expression and in-depth mechanism of SIRT1 in the hypothalamus in SOD1G93A transgenic mice. We found that SIRT1 was overexpressed in the hypothalamus after motor symptom onset. In addition, SIRT1 interacted with prepro-orexin, a molecule involved in energy balance and the sleep/wake cycle, in both preclinical and clinical ALS regardless of whether SIRT1 levels were elevated. These findings indicate that SIRT1 might participate in sleep and metabolic changes in ALS, suggesting that SIRT1 is a new target for ALS treatment.

Abstract Background The evaluation of respiratory system health status in hospitalized patients is usually based on many laboratory examinations and imaging examinations. Medical examinations require a lot of manpower, material resources, financial resources, and may cause a certain degree of mechanical damage and radiation damage. It is not easily used widely and economically to assess the respiratory health status of community adults. Therefore, researchers developed a brief adult respiratory system health status scale-community version (BARSHSS-CV) and tested its reliability and validity. Methods Using clinical characteristics and pathogenic factors of respiratory system diseases as a theoretical basis and through reference to relevant literature, researchers developed an initial scale. A randomized cluster sampling strategy was used to recruit adults in the communities of Baoding City, Shijiazhuang City, Cangzhou city and Chifeng City in China. Researchers randomly selected 1 district from each city. Subsequently, 4 communities were respectively randomly selected from 4 districts. Then, researchers conducted the questionnaire survey in 4 communities. Finally, researchers investigated 615 community adults. 584 valid questionnaires were recovered. By applying exploratory factor analysis, confirmatory factor analysis, content validity index, Cronbach’s α coefficient, mean inter-item correlation coefficient and test-retest reliability, researchers tested the reliability and validity of scale and created the final BARSHSS-CV. Results BARSHSS-CV Cronbach’s α=0.951, content validity = 0.933, test-retest reliability = 0.963 and factor cumulative contribution rate = 67.168% by exploratory factor analysis. By confirmatory factor analysis, Chi square value (χ2) was 442.117, degrees of freedom (df) was 161, Chi square value/degrees of freedom (χ2 /df) was 2.746, root-mean-square error of approximation (RMSEA) was 0.065, goodness of fit index (GFI) was 0.902, incremental fit index (IFI) was 0.955, comparative fit index (CFI) was 0.955, normed fit index (NFI) was 0.931, Tueker-Lewis index (TLI) was 0.947. BARSHSS-CV consisted of 20 items and 3 dimensions. Conclusions BARSHSS-CV with good test-retest reliability and content/construct validity is a brief and economical tool for assessing the state of respiratory system amongst adult communities. BARSHSS-CV may help medical staff in community primary medical institutions quickly, conveniently and economically assess the status of respiratory system and the main problems of respiratory system in community adults.

Abstract Background Haze leads to many direct serious public health impacts. Understanding haze related knowledge can not only help adolescents organize health protection awareness to prevent the harmful effects that haze has on the body, but also promote their normal growth and development. Methods By considering, as the theoretical basis, the reasons behind the formation of haze and the underlying mechanisms of the diseases that it causes, in addition to also investigating extensive literature references, our research team developed the Adolescent Haze Related Knowledge Awareness Assessment Scale (AHRKAAS-I). After 6 experts reviewed AHRKAAS-I, and 6 adolescents tested the scale, the research team further revised and improved AHRKAAS-I to form AHRKAAS-II. After which, researchers randomly selected 2 districts from the 20 districts of Baoding, and subsequently randomly selected 2 middle schools from these 2 districts. Conducting a stratified cluster sampling method, considering class as a unit, the research team randomly selected 22 classes. Finally, a total of 1100 adolescents were investigated and 1034 valid questionnaires were recovered. By analyzing the data of 1034 valid questionnaires, the researchers tested the reliability and validity of the scale and obtained the final scale (AHRKAAS). Results AHRKAAS Cronbach’s α=0.923, content validity = 0.940, criterion validity = 0.444, and factor cumulative contribution rate = 66.178% by exploratory factor analysis. Using confirmatory factor analysis, Chi square value = 662.780, degrees of freedom = 242, Chi square value/degrees of freedom = 2.739, root-mean-square error of approximation = 0.049, goodness of fit index = 0.929, adjusted goodness of fit index = 0.905, comparative fit index = 0.964, normed fit index = 0.944, and Tueker-Lewis index = 0.955. AHRKAAS consisted of 25 items and 4 dimensions. Conclusion AHRKAAS with a good reliability and validity can be used to assess the cognition level of haze related knowledge among the adolescents, help medical workers and coordinators in schools when conducting targeted behavior interventions. Furthermore, it can be used for health guidance for adolescents relating to the health prevention of haze.

Ionocovalency (IC), a quantitative dual nature of the atom, is defined and correlated with quantum-mechanical potential to describe quantitatively the dual properties of the bond. Orbiotal hybrid IC model scale, IC, and IC electronegativity scale, XIC, are proposed, wherein the ionicity and the covalent radius are determined by spectroscopy. Being composed of the ionic function I and the covalent function C, the model describes quantitatively the dual properties of bond strengths, charge density and ionic potential. Based on the atomic electron configuration and the various quantum-mechanical built-up dual parameters, the model formed a Dual Method of the multiple-functional prediction, which has much more versatile and exceptional applications than traditional electronegativity scales and molecular properties. Hydrogen has unconventional values of IC and XIC, lower than that of boron. The IC model can agree fairly well with the data of bond properties and satisfactorily explain chemical observations of elements throughout the Periodic Table.