To meet the high-precision positioning requirements for hybrid machining units, this article presents a geometric error modeling and source error identification methodology for a serial–parallel hybrid kinematic machining unit (HKMU) with five axis. A minimal kinematic error modeling of the serial–parallel HKMU is established with screw-based method after elimination of redundant errors. A set of composite error indices is formulated to describe the terminal accuracy distribution characteristics in a quantitative manner. A modified projection method is proposed to determine the actual compensable and noncompensable source errors of the HKMU by identifying such transformable source errors. Based on this, the error compensation and comparison analysis are carried out on the exemplary HKMU to numerically verify the effectiveness of the proposed modified projection method. The geometric error evaluations reveal that the parallel module has a larger impacts on the terminal accuracy of the platform of the HKMU than the serial module. The error compensation results manifest that the modified projection method can find additional compensable source errors and significantly reduce the average and maximum values of geometric errors of the HKMU. Hence, the proposed methodology can be applied to improve the accuracy of kinematic calibration of the compensable source errors and can reduce the difficulty and workload of tolerance design for noncompensable source errors of such serial–parallel hybrid mechanism.

This paper retrospectively analysed the prevalence of macrolide-resistant Mycoplasma pneumoniae (MRMP) in some parts of China. Between January 2013 and December 2019, we collected 4,145 respiratory samples, including pharyngeal swabs and alveolar lavage fluid. The highest PCR-positive rate of M. pneumoniae was 74.5% in Beijing, the highest resistance rate was 100% in Shanghai, and Gansu was the lowest with 20%. The highest PCR-positive rate of M. pneumoniae was 74.5% in 2013, and the highest MRMP was 97.4% in 2019; the PCR-positive rate of M. pneumoniae for adults in Beijing was 17.9% and the MRMP was 10.48%. Among the children diagnosed with community-acquired pneumonia (CAP), the PCR-positive and macrolide-resistant rates of M. pneumoniae were both higher in the severe ones. A2063G in domain V of 23S rRNA was the major macrolide-resistant mutation, accounting for more than 90%. The MIC values of all MRMP to erythromycin and azithromycin were ≥ 64 μg/ml, and the MICs of tetracycline and levofloxacin were ≤ 0.5 μg/ml and ≤ 1 μg/ml, respectively. The macrolide resistance varied in different regions and years. Among inpatients, the macrolide-resistant rate was higher in severe pneumonia. A2063G was the common mutation, and we found no resistance to tetracycline and levofloxacin.

Based on 30 high-resolution U-Th dating controls, we reconstruct stalagmite δ18O records from 45 to 15 thousand years ago (ka B.P., before AD 1950) from the Shizhu Cave, which is located in southwestern China under the influence of both the Indian Summer Monsoon (ISM) and the East Asian Summer Monsoon (EASM). By integrating with the other stalagmite δ18O records in Asia during the middle to late last glacial, our results reveal two main moisture trajectories: one from the Indian Ocean, through the Shizhu Cave towards central China, and the other from the Pacific Ocean to central and northern China. The systematic decrease of the average values of stalagmite δ18O records from oceans to inland China reveals a spatial pattern of water vapour fractionation and moisture trajectory during the middle to late last glacial. In contrast, the variation amplitude, which is defined as the departures apart from the background δ18O records during Heinrich stadials 1 to 4 (HS1–HS4), show an increasing trend from the coastal oceans to mid-latitude inland China, presenting a ‘coastal-inland’ pattern, which can be interpreted by the enhanced East Asian Winter Monsoon (EAWM) and the weakened EASM. More specifically, the enriched stalagmite δ18O records in the EASM region during HS1 to HS4 are caused by the decreased summer rainfall amount or/and the increased proportion of summer moisture resources from the Pacific Ocean. These new observations deepen our understanding of the complicated stalagmite δ18O records in the EASM region.

Hydrophobicity, swellability, and dispersion are important properties for organo-montmorillonites (OMnt) and have yet to be fully characterized for all OMnt configurations. The purpose of the present work was to examine the preparation of OMnt from the reaction of Ca2+-montmorillonite (Ca2+-Mnt) with a high concentration of surfactant and to reveal the relevant properties of hydrophobicity and dispersion of the resultant OMnt. A series of OMnt samples were prepared using a small amount of water and cetyltrimethylammonium bromide (CTAB) with a concentration more than the CTAB critical micelle concentration (CMC). The relationship between OMnt microstructure and the hydrophobicity and swellability properties was investigated in detail. The resulting OMnt samples were characterized using powder X-ray diffraction patterns (XRD), Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric and differential thermogravimetry (TG-DTG), water contact angle tests, swelling indices, and transmission electron microscopy (TEM). The addition of CTAB and water in the OMnt preparation affected the OMnt microstructure and properties. An increase in CTAB concentration led to a more ordered arrangement of cetyltrimethylammonium (CTA+) cations in the interlayer space of the OMnt and a large amount of CTA+ cations on the outer surfaces of the OMnt. The swelling indices and the water contact angles of OMnt samples depended on the distribution of the CTAB surfactant on OMnt and the orientation of the surfactant hydrophilic groups on the inner and on the outer surfaces of OMnt. A maximum swelling index of 39 mL/g in xylene was achieved with an average water contact angle of 62.0° ± 2.0° when the amount of CTAB added was 2 times the cation exchange capacity (CEC) of Mnt and the lowest water to dry Mnt mass ratio was 3 during the preparation of OMnt samples. The platelets of OMnt aggregated together in xylene by electrostatic attraction and by hydrophobic interactions.

The Tuluanshan Formation of the eastern Coastal Range of Taiwan overlies an andesitic core complex presumed to be the source of hydrothermal fluids responsible for the Si- and Mg-rich mineralization of sepiolite and palygorskite (attapulgite) which are found in veins within fissures and in fracture zones of the volcanic rocks of the region. This study was undertaken in order to understand these relationships better by characterizing sepiolite and palygorskite in this Formation and by examining their occurrence and distribution in the Tungho (TH) and Chunjih (CJ) areas. Samples were analyzed using X-ray diffraction (XRD), thermal analysis, Fourier-transform infrared (FTIR) spectroscopy, and petrographic, scanning (SEM), and transmission (TEM) electron microscopic methods. Sepiolite and palygorskite are blocky and earthy-type materials that display fibrous characteristics when viewed using TEM and SEM and occurred alone or with chalcedony in veins. The fibers of blocky sepiolite are commonly intercalated with smectite but the earthy type of sepiolite and palygorskite observed in this study displayed precipitation from fluid enriched in Si, Al, Mg, and minor Fe and depleted in other ions at an earlier stage of offset of the andesitic veins. Continuation of reverse faulting and high shearing stress caused the precipitation of a significant quantity of interlaminated sepiolite. Sepiolite and palygorskite were formed at an earlier stage of fluid interaction relative to smectite in the Tuluanshan Formation.

Montmorillonite (Mnt)-based solid acids have a wide range of applications in catalysis and adsorption of pollutants. For such solid acids, the acidic characteristic often plays a significant role in these applications. The objective of the current study was to examine the effects of H3PO4-activation and supporting WO3 on the textural structure and surface acidic properties of Mnt. The Mnt-based solid acid materials were prepared by H3PO4 treatment and an impregnation method with a solution of ammonium metatungstate (AMT) and were examined as catalysts in the dehydration of glycerol to acrolein. The catalysts were characterized by nitrogen adsorption-desorption, powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance ultraviolet-visible (DR UV-Vis) spectroscopy, temperature programmed desorption of NH3 (NH3-TPD), diffuse reflectance Fourier-transform infrared (DR FTIR) spectroscopy of adsorbed pyridine, and thermogravimetric (TG) analyses. The phosphoric acid treatment of Mnt created Brönsted and Lewis acid sites and led to increases in specific surface areas, porosity, and acidity. WO3 species influenced total acidity, acid strength, the numbers of Brönsted and Lewis acid sites, and catalytic performances. A high turnover frequency (TOF) value (31.2 h−1) based on a maximal 60.7% yield of acrolein was reached. The correlation of acrolein yield with acidic properties indicated that the cooperative role of Brönsted and Lewis acid sites was beneficial to the formation of acrolein and a little coke deposition (<3.3 wt.%). This work provides a new idea for the design of solid acid catalysts with cooperative Brönsted and Lewis acidity for the dehydration of glycerol.

Rodents and shrews are major reservoirs of various pathogens that are related to zoonotic infectious diseases. The purpose of this study was to investigate co-infections of zoonotic pathogens in rodents and shrews trapped in four provinces of China. We sampled different rodent and shrew communities within and around human settlements in four provinces of China and characterised several important zoonotic viral, bacterial, and parasitic pathogens by PCR methods and phylogenetic analysis. A total of 864 rodents and shrews belonging to 24 and 13 species from RODENTIA and EULIPOTYPHLA orders were captured, respectively. For viral pathogens, two species of hantavirus (Hantaan orthohantavirus and Caobang orthohantavirus) were identified in 3.47% of rodents and shrews. The overall prevalence of Bartonella spp., Anaplasmataceae, Babesia spp., Leptospira spp., Spotted fever group Rickettsiae, Borrelia spp., and Coxiella burnetii were 31.25%, 8.91%, 4.17%, 3.94%, 3.59%, 3.47%, and 0.58%, respectively. Furthermore, the highest co-infection status of three pathogens was observed among Bartonella spp., Leptospira spp., and Anaplasmataceae with a co-infection rate of 0.46%. Our results suggested that species distribution and co-infections of zoonotic pathogens were prevalent in rodents and shrews, highlighting the necessity of active surveillance for zoonotic pathogens in wild mammals in wider regions.

SARS-CoV-2 rapidly spreads among humans via social networks, with social mixing and network characteristics potentially facilitating transmission. However, limited data on topological structural features has hindered in-depth studies. Existing research is based on snapshot analyses, preventing temporal investigations of network changes. Comparing network characteristics over time offers additional insights into transmission dynamics. We examined confirmed COVID-19 patients from an eastern Chinese province, analyzing social mixing and network characteristics using transmission network topology before and after widespread interventions. Between the two time periods, the percentage of singleton networks increased from 38.9$ \% $ to 62.8$ \% $$ (p<0.001) $; the average shortest path length decreased from 1.53 to 1.14 $ (p<0.001) $; the average betweenness reduced from 0.65 to 0.11$ (p<0.001) $; the average cluster size dropped from 4.05 to 2.72 $ (p=0.004) $; and the out-degree had a slight but nonsignificant decline from 0.75 to 0.63 $ (p=0.099). $ Results show that nonpharmaceutical interventions effectively disrupted transmission networks, preventing further disease spread. Additionally, we found that the networks’ dynamic structure provided more information than solely examining infection curves after applying descriptive and agent-based modeling approaches. In summary, we investigated social mixing and network characteristics of COVID-19 patients during different pandemic stages, revealing transmission network heterogeneities.

Childhood maltreatment has been suggested to have an adverse impact on neurodevelopment, including microstructural brain abnormalities. Existing neuroimaging findings remain inconsistent and heterogeneous. We aim to explore the most prominent and robust cortical thickness (CTh) and gray matter volume (GMV) alterations associated with childhood maltreatment. A systematic search on relevant studies was conducted through September 2022. The whole-brain coordinate-based meta-analysis (CBMA) on CTh and GMV studies were conducted using the seed-based d mapping (SDM) software. Meta-regression analysis was subsequently applied to investigate potential associations between clinical variables and structural changes. A total of 45 studies were eligible for inclusion, including 11 datasets on CTh and 39 datasets on GMV, consisting of 2550 participants exposed to childhood maltreatment and 3739 unexposed comparison subjects. Individuals with childhood maltreatment exhibited overlapped deficits in the median cingulate/paracingulate gyri simultaneously revealed by both CTh and GM studies. Regional cortical thinning in the right anterior cingulate/paracingulate gyri and the left middle frontal gyrus, as well as GMV reductions in the left supplementary motor area (SMA) was also identified. No greater regions were found for either CTh or GMV. In addition, several neural morphology changes were associated with the average age of the maltreated individuals. The median cingulate/paracingulate gyri morphology might serve as the most robust neuroimaging feature of childhood maltreatment. The effects of early-life trauma on the human brain predominantly involved in cognitive functions, socio-affective functioning and stress regulation. This current meta-analysis enhanced the understanding of neuropathological changes induced by childhood maltreatment.

Coastal eutrophication and hypoxia remain a persistent environmental crisis despite the great efforts to reduce nutrient loading and mitigate associated environmental damages. Symptoms of this crisis have appeared to spread rapidly, reaching developing countries in Asia with emergences in Southern America and Africa. The pace of changes and the underlying drivers remain not so clear. To address the gap, we review the up-to-date status and mechanisms of eutrophication and hypoxia in global coastal oceans, upon which we examine the trajectories of changes over the 40 years or longer in six model coastal systems with varying socio-economic development statuses and different levels and histories of eutrophication. Although these coastal systems share common features of eutrophication, site-specific characteristics are also substantial, depending on the regional environmental setting and level of social-economic development along with policy implementation and management. Nevertheless, ecosystem recovery generally needs greater reduction in pressures compared to that initiated degradation and becomes less feasible to achieve past norms with a longer time anthropogenic pressures on the ecosystems. While the qualitative causality between drivers and consequences is well established, quantitative attribution of these drivers to eutrophication and hypoxia remains difficult especially when we consider the social economic drivers because the changes in coastal ecosystems are subject to multiple influences and the cause–effect relationship is often non-linear. Such relationships are further complicated by climate changes that have been accelerating over the past few decades. The knowledge gaps that limit our quantitative and mechanistic understanding of the human-coastal ocean nexus are identified, which is essential for science-based policy making. Recognizing lessons from past management practices, we advocate for a better, more efficient indexing system of coastal eutrophication and an advanced regional earth system modeling framework with optimal modules of human dimensions to facilitate the development and evaluation of effective policy and restoration actions.

A systematic simulation study of the $n/m=1/1$ instability driven by energetic counter-passing particles in tokamak plasmas has been carried out using the kinetic-MHD (Magnetohydrodynamics) hybrid code M3D-K. The safety factor's radial profile is monotonically increasing with central value $q_0$ less than unity. The linear simulation results show that the instability is either a $m/n=1/1$ energetic particle mode or a $m/n=1/1$ global Alfvén eigenmode depending on the value of the central safety factor. The mode frequencies are close to the tip of Alfvén continuum spectrum at the magnetic axis. The excited modes are radially localized near the magnetic axis well within the safety factor $q=1$ surface. The main wave particle resonance is found to be $\omega _\phi +2\omega _\theta =\omega$, where ω is the mode frequency. The nonlinear simulation results show that there is a long period of quasi-steady-state saturation phase with frequency chirping up after initial saturation. Correspondingly, the energetic particle distribution with low energies is flattened in the core of the plasma. After this quasi-steady phase, the mode amplitude grows again and frequency jumps down to a low value corresponding to a new mode similar to the energetic co-passing particle-driven low-frequency fishbone while the energetic particle distribution is flattened for higher energies in the core of plasma.

Adolescence is a significant period for the formation of relationship networks and the development of internalizing problems. With a sample of Chinese adolescents (N = 3,834, 52.01% girls, Mage = 16.68 at Wave 1), the present study aimed to identify the configuration of adolescents’ relationship qualities from four important domains (i.e., relationship quality with mother, father, peers, and teachers) and how distinct profiles were associated with the development of internalizing problems (indicated by depressive and anxiety symptoms) across high school years. Latent profile analysis identified a five-profile configuration with four convergent profiles (i.e., relationship qualities with others were generally good or bad) and one “Father estrangement” profile (i.e., the relationship quality with others were relatively good but that with father was particularly poor). Further conditional latent growth curve analysis indicated the “Father estrangement” profile was especially vulnerable to an increase in the internalizing problems as compared with other relationship profiles. This study contributes to understanding the characteristics of interpersonal relationship qualities and their influences on adolescent internalizing problems in a non-Western context. Results were further discussed from a culturally specific perspective.

An experimental investigation of the stereocamera's systematic error is carried out to optimize three-dimensional (3-D) dust observation on the HL-2A tokamak. It is found that a larger 3-D region occupied by all calibration points is able to reduce the 3-D reconstruction systematic error of the stereocamera. In addition, the 3-D reconstruction is the most accurate around the region where the calibration points are located. Based on these experimental results, the design of the stereocamera on the HL-2A tokamak is presented, and a set of practical procedures to optimize the 3-D reconstruction accuracy of the stereocamera are proposed.

To integrate the uneven terrain adaptivity of legged robots and the fast capacity of wheeled robots on even terrains, a four wheel-legged robot is addressed and the cooperative control strategy of wheels and legs based on attitude balance is investigated. Firstly, the kinematics of wheel-legged robot is analyzed, which contains the legged and wheeled motion modal. Secondly, the cooperative control strategy of wheel-legged robot based on attitude balance is proposed. The attitude is calculated by using the quaternion method and complementary filtering, and the attitude stability control of the wheel-legged robot is studied. The trajectory planning of leg motion including walk and trot gait is implemented, and the differential control of wheeled motion is deduced. And then, the cooperative motion control of wheels and legs is achieved by keeping the attitude balance of robot body. Finally, a small prototype is set up to validate the feasibility and effectiveness of proposed method. The experimental results show that the established wheel-legged robot can do walk, trot, and wheel-leg compound motion to overcome many complex terrains and environments.

Coronavirus disease 2019 (COVID-19) asymptomatic cases are hard to identify, impeding transmissibility estimation. The value of COVID-19 transmissibility is worth further elucidation for key assumptions in further modelling studies. Through a population-based surveillance network, we collected data on 1342 confirmed cases with a 90-days follow-up for all asymptomatic cases. An age-stratified compartmental model containing contact information was built to estimate the transmissibility of symptomatic and asymptomatic COVID-19 cases. The difference in transmissibility of a symptomatic and asymptomatic case depended on age and was most distinct for the middle-age groups. The asymptomatic cases had a 66.7% lower transmissibility rate than symptomatic cases, and 74.1% (95% CI 65.9–80.7) of all asymptomatic cases were missed in detection. The average proportion of asymptomatic cases was 28.2% (95% CI 23.0–34.6). Simulation demonstrated that the burden of asymptomatic transmission increased as the epidemic continued and could potentially dominate total transmission. The transmissibility of asymptomatic COVID-19 cases is high and asymptomatic COVID-19 cases play a significant role in outbreaks.