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Climate warming and anthropogenic disturbances result in permafrost degradation in cold regions, including in the Qilian Mountains. These changes lead to extensive hillslope thermokarst (HT) formation, such as retrogressive thaw slumps, active-layer detachment slides, and thermal erosion gullies. These in turn cause, e.g., degradation of local vegetation, economic losses, infrastructure damages, and threats to human safety. However, despite its importance, there is currently no thermokarst inventory for the Qilian Mountains. Through manual visual interpretation and field validation, we therefore produce the first quantification of HT features. We count a total of 1064 HT features, with 67 % located in the upper reaches of the Heihe River basin, which encompasses ∼ 13 % of the Qilian Mountains region. We further identified that 187 HT features (18 %) existed before 2010, while the remaining 874 (82 %) were initiated in the recent period. More specifically, 392 sites (37 %) were initiated during 2010–2015 and 482 (45 %) after 2015. Thermokarst terrain is observed primarily in areas with shallow active-layer depths (average thickness 2.98 m) on northern shaded slopes of 3–25°, with low solar radiation and moderate elevations ranging from 3200 to 4000 m. This first inventory of HT features is an important and missing piece in documenting changes on the Qinghai–Tibetan Plateau, and this new dataset also provides an important basis for further studies, such as automated extraction of HT features, susceptibility analysis of HT, and estimation of losses caused by HT. The datasets are available from the National Tibetan Plateau/Third Pole Environment Data Center and can be downloaded from https://doi.org/10.11888/Cryos.tpdc.300805 (Peng and Yang, 2023).

ABSTRACT: Although high-concentrate diet feeding can temporarily increase milk production, it can cause a series of metabolic diseases, such as subacute ruminal acidosis (SARA) and milk fat depression. The main purpose of this experiment was to study the effects of a high-concentrate diet on the inflammatory response, oxidative stress, and milk fat synthesis in the mammary gland of dairy cows. Twelve Holstein cows equipped with rumen fistulas were randomly divided into 2 groups, each with 6 cows, fed a low-concentrate diet (LC) and a high-concentrate diet (HC). On d 20 and 21 of the experiment, rumen fluid was collected to measure pH, and milk samples were collected for milk component analysis and lipopolysaccharide (LPS) concentration testing. On d 21, mammary vein blood was collected to detect the LPS concentration. At the end of the 21-d experimental period, mammary gland tissue was collected, and the expression of inflammatory response-, oxidative stress-, and milk fat synthesis-related genes and proteins in the mammary gland was analyzed by real-time quantitative PCR and western blot. The pH of rumen fluid in the HC group was significantly lower than that in the LC group, and the pH of 2 time points in the HC group was lower than 5.6, indicating that a high-concentrate diet induced SARA. The LPS concentration of the peripheral blood in HC group increased significantly compared with that in the LC group. For the inflammatory response, the proinflammatory cytokines (IL-6 and IL-1α) and innate immune factors (lingual antimicrobial peptide and tracheal antimicrobial peptide) in the mammary gland of the HC group were significantly increased, and the TLR4-NF-κB signaling pathway was activated. For oxidative stress, after HC diet feeding, the content of malondialdehyde in mammary vein blood and mammary gland tissue increased, the content of glutathione in mammary vein blood decreased, the activity of superoxide dismutase and the total antioxidant capacity in mammary gland tissue and mammary vein blood decreased, and the expression of antioxidant enzymes and antioxidant transcription factor nuclear factor, erythroid 2 like 2 (NFE2L2) in mammary gland decreased. For milk fat metabolism, HC diet feeding reduced the milk fat content in milk samples and the triacylglycerol content in the mammary gland and inhibited the expression of de novo synthase (ACACA and FASN), long-chain fatty acid converting enzymes (ACSL1 and SCD), fatty acid transporters (CD36, FATP, FABP3, and LPL), triacylglycerol synthase (AGPAT6, DGAT1, and LPIN1), lipid droplet releasing enzyme (PLIN1), and transcription factors sterol regulatory element binding protein (SREBP1) and peroxisome proliferator activated receptor gamma (PPARG). In summary, a HC diet can induce SARA with increased concentration of LPS in the peripheral vein, stimulate inflammatory reactions and oxidative stress, and inhibit milk fat synthesis in the mammary gland of dairy cows.

Satellite-derived aerosol optical depth (AOD) is an indispensable parameter when conducting studies related to atmospheric environment, climate change, and biogeochemical cycle. However, current satellite-derived AOD products are limited in related applications due to the large proportion of missing data, and the existed methods mainly concentrate on recovering AOD from polar-orbit satellite sensors. In order to solve these issues and take full use of the preponderance of geostationary satellite sensors in high frequency observation, we propose a spatiotemporal AOD recovery framework integrating multi-time scale AOD products based on the nested Bayesian maximum entropy methodology (NBME), aimed to obtain satellite-derived AOD datasets with low data missing and high accuracy. The experiment results show that the spatial coverage of AOD datasets increases from 20.5% to 70.0%, and the R2 and RMSE of the recovered AOD against ground-based AERONET AOD are approximately 0.62 and 0.19, respectively. Moreover, the further simulated experiments indicate that the proposed method also performs better relatively when comparing with other popular recovery methods. Therefore, the proposed NBME recovery method can obtain a more convincing product both in applicable accuracy and visual quality.

A positioning system for ultra-wideband (UWB) electric micro-tillers suitable for complex greenhouse environments was designed as the basis for realizing unmanned micro-tillers to address the problem of the frequent safety accidents of existing micro-tillers. First, the positioning base station and tag were designed on the basis of the STM32 and DW1000 chip hardware. The real-time coordinate display of the micro-tiller in the greenhouse could also be realized with the design of the upper computer software. Then, the realization method of the positioning function, including the analysis of time difference of arrival (TDOA) and two-way ranging (TWR) positioning methods, and the selection of the best Taylor positioning algorithm through a MATLAB simulation were studied to reduce the influence of noise and measurement errors on measurement accuracy. Finally, a positioning system accuracy test was conducted. Test results revealed that the maximum positioning error of the micro-tiller positioning system is no more than 6 cm, and the average error is 4.4 cm. The optimized positioning error is reduced by 10.2 %, considering that the influence of the base station location on the accuracy. The positioning system of the greenhouse electric micro-tiller designed in this paper demonstrates a stable performance and positioning accuracy to meet the needs of greenhouse rotary tillage operations. This system has certain theoretical importance and reference value for the development of precise positioning technology for working tools in the greenhouse and the further realization of unmanned rotary tillage operations.

A six-wheeled companion exploration robot with an adaptive climbing mechanism is proposed and released for the complicated terrain environment of planetary exploration. Benefiting from its three-rocker-arm structure, the robot can adapt to complex terrain with its six wheels in contact with the ground during locomotion, which improves the stability of the robot. When the robot moves on the flat ground, it moves forward through the rotation of the wheels. When it encounters obstacles in the process of moving forward, the front obstacle-crossing wheels hold the obstacle, and the rocker arms on both sides rotate themselves with mechanical adaptivity to drive the robot to climb and cross the obstacle like crab legs. Furthermore, a parameterized geometric model is established to analyze the motion stability and the obstacle-crossing performance of the robot. To investigate the feasibility and correctness of design theory and robot scheme, a group of design parameters of the robot are determined. A prototype of the robot is developed, and the experiment results show that the robot can maintain stability in rugged terrain environments and has a certain ability to surmount obstacles.

Currently, near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) have become a research hotspot, however, the NIR phosphors continue to face the problems of narrowband emission and poor thermal stability. Therefore, in order to solve these problems, La3SnGa5O14:xCr3+ phosphors with ultra-broadband NIR emission were obtained by multiple lattice sites occupation, featuring ultra-broadband emission in the range of 650–1300 nm with full width at half-maximum (FWHM) up to 333 nm under 437 nm excitation. By tuning the concentration of Cr3+, the FWHM value can reach 333–417 nm La3SnGa5O14:Cr3+ also exhibits favorable thermal stability, maintaining 90.5% and 67% of the initial intensity at 373 K and 423 K, respectively. The NIR pc-LEDs were manufactured by combining the blue light chip with La3SnGa5O14:Cr3+ phosphor. When the NIR pc-LED was switched off, no image could be generated from the infrared camera. Instead, the image captured by the infrared camera was visible in the light of the NIR pc-LED lamp. Such results imply that La3SnGa5O14:Cr3+ may be a prospective candidate for future biological accurate nondestructive detection and night-vision technology.

Abstract Objective To compare the accuracy of the European Randomized Study of Screening for Prostate Cancer (ERSPC) RC, MRI‐ERSPC‐RC, and Prostate Biopsy Collaborative Group (PBCG) RC in patients undergoing transperineal prostate biopsy. Patients and methods We identified 392 patients who underwent mpMRI before transperineal prostate biopsy across multiple public and private institutions between January 2017 and August 2019. The estimated probabilities of detecting PCa and significant PCa were calculated using the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC. Receiver operating characteristic (ROC) curves for each calculator were generated and the area underneath the curve (AUC) was compared. Calibration and clinical utility were assessed with calibration plots and decision curve analysis, respectively. Results PCa was detected in 285 patients (72.7%) with significant PCa found in 200 patients (51.1%). ROC curve analysis found the MRI‐ERSPC‐RC outperformed the ERSPC‐RC and PBCG‐RC. For the prediction of PCa, the AUC was 0.756, 0.696, and 0.675 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively. The AUC for the prediction of significant PCa was 0.803, 0.745, and 0.746 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively. Conclusions Our study validated the ERSPC‐RC, MRI‐ERSPC‐RC, and PBCG‐RC in a cohort undergoing transperineal prostate biopsy with the MRI‐ERSPC‐RC performing the best. These RCs may enable improved shared decision making and help to guide patient selection for biopsy.

Evapotranspiration (ET) is a major component of the land surface process involved in energy fluxes and energy balance, especially in the hydrological cycle of agricultural ecosystems. While many models have been developed as powerful tools to simulate ET, there is no agreement on which model best describes the loss of water to the atmosphere. This study focuses on two aspects, evaluating the performance of four widely used ET models and identifying parameters, and the physical mechanisms that have significant impacts on the model performance. The four tested models are the Shuttleworth–Wallace (SW) model, Penman–Monteith (PM) model, Priestley–Taylor and Flint–Childs (PT–FC) model, and advection–aridity (AA) model. By incorporating the mathematically rigorous thermodynamic integration algorithm, the Bayesian model evidence (BME) approach is adopted to select the optimal model with half-hourly ET observations obtained at a spring maize field in an arid region. Our results reveal that the SW model has the best performance, and the extinction coefficient is not merely partitioning the total available energy into the canopy and surface but also including the energy imbalance correction. The extinction coefficient is well constrained in the SW model and poorly constrained in the PM model but not considered in PT–FC and AA models. This is one of the main reasons that the SW model outperforms the other models. Meanwhile, the good fitting of SW model to observations can counterbalance its higher complexity. In addition, the detailed analysis of the discrepancies between observations and model simulations during the crop growth season indicate that explicit treatment of energy imbalance and energy interaction will be the primary way of further improving ET model performance.

Introduction Multiple hospitalisations towards the end of life is an indicator of poor-quality care. Understanding the characteristics of patients who experience hospitalisations at the end-of-life and how they vary is important for improved care planning. Objectives To describe socio-demographic and clinical characteristics of patients diagnosed with serious mental illness who experienced multiple hospitalisations in the last 90 days of life. Methods Data for all adult patients with a diagnosis of serious mental illness who died in 2018-2019 in England, UK were extracted from the National Mental Health Services Data Set linked with Hospital Episode Statistics and death registry data. Variables of interest included age, gender, marital status, underlying and contributory cause of death, ethnicity, place of death, deprivation status, urban-rural indicator, and patient’s region of residence. The number of hospitalisations and patient’s sociodemographic & clinical were described using descriptive statistics and percentages, respectively. Results Of the 45924 patients, 38.1% (n=17505, Male=42.9%, Female=57.1%, Mean age:78.4) had at least one hospitalisation in the last 90 days of life. The median number of hospitalisations was 2(StdDev:1.64, Minimum=1,Maximum=23). Most of those hospitalised (n=11808, 67.5%), died in a health care establishment (e.g. Hospital or hospice). There were marked geographic differences in the proportions of hospitalisations.The North West region of England recorded the most hospitalisations (n= 2906,16.6%), compared to other regions. Conclusions Further analysis is needed to understand factors independently associated with hospitalisations in people with serious mental illness. Funding: This project is supported by the National Institute for Health Research (NIHR) Applied Research Collaborations (ARC) South London.

This paper proposes an innovative and systematic approach for synthesizing mechanical structures of wheeled mobile robots. The principle and terminologies used for the proposed synthesis method are presented by adopting the concept of modular design, isomorphic and non-isomorphic, and set theory with its associated combinatorial mathematics. The modular-based innovative synthesis and design of wheeled robots were conducted at two levels. Firstly at the module level, by creative design and analysing the structures of classic wheeled robots, a wheel module set containing four types of wheel mechanisms, a suspension module set consisting of five types of suspension frames and a chassis module set composed of five types of rigid or articulated chassis were designed and generalized. Secondly at the synthesis level, two kinds of structure synthesis modes, namely the isomorphic-combination mode and the non-isomorphic combination mode were proposed to synthesize mechanical structures of wheeled robots; which led to 241 structures for wheeled mobile robots including 236 novel ones. Further, mathematical models and a software platform were developed to provide appropriate and intuitive tools for simulating and evaluating performance of the wheeled robots that were proposed in this paper. Eventually, physical prototypes of sample wheeled robots/rovers were developed and tested so as to prove and validate the principle and methodology presented in this paper.

This paper presents a novel bio-inspired modular robotic arm that is purely evolved and developed from a mechanical stem cell. Inspired by stem cell whilst different from the other robot "cell" or "molecule", a fundamental mechanical stem cell is proposed leading to the development of mechanical cells, bones and a Sarrus-linkage-based muscle. Using the proposed bones and muscles, a bio-inspired modular-based five-degrees-of-freedom robotic arm is developed. Then, kinematics of the robotic arm is investigated which is associated with an optimization-method-based numerical iterative algorithm leading to the inverse kinematic solutions through solving the non-linear transcendental equations. Subsequently, numerical example of the proposed robotic arm is provided with simulations illustrating the workspace and inverse kinematics of the arm. Further, a prototype of the robotic arm is developed which is integrated with low-level control systems, and initial motion and manipulation tests are implemented. The results indicate that this novel robotic arm functions appropriately and has the virtues of lower cost, larger workspace, and a simpler structure with more compact size.

Using a formula for the total settlement of deep soil and the Winkler foundation model, the force model for underground pipelines is simplified to obtain the ultimate bending moments and to calculate the stress and strain due to double parallel shield tunneling construction. The effects of soil conditions, tunnel horizontal spacing L, pipeline material, pipeline depth h and soil loss ratioηl/ηf on the force on an underground pipeline are investigated. The results show that changing the soil conditions and value of L can have a significant effect on the shape and magnitude of the pipeline’s ultimate moment curve, although changing the value of h has less of an effect. It is found that the larger the bending stiffness of the pipeline, the larger the distribution range of the ultimate bending moment and its peak value, but there is less of an effect on the shape of the curve. Changes in the ratioηl/ηf have some influence on both the shape of the curve and the values of the bending stiffness of the pipeline.

The identification of priority management areas (PMAs) is essential for the control of non-point-source (NPS) pollution, especially for a large-scale watershed. However, previous studies have typically focused on small-scale catchments adjacent to specific assessment points; thus, the interactions between multiple river points remain poorly understood. In this study, a multiple-assessment-point PMA (MAP-PMA) framework was proposed by integrating the upstream sources and the downstream transport aspects of NPS pollution. Daning River watershed was taken as a case study in this paper, which has demonstrated that the integration of the upstream input changes was vital for the final PMAs map, especially for downstream areas. Contrary to conventional wisdom, this research recommended that the NPS pollutants could be best controlled among the upstream high-level PMAs when protecting the water quality of the entire watershed. The MAP-PMA framework provided a more cost-effective tool for the establishment of conservation practices, especially for a large-scale watershed.

Airborne Laser Scanning (ALS) has been a well-established tool for the measurement of surface topography as well as for the estimation of biophysical canopy variables, such as tree height and vegetation density. By combining GPS and INS together, ALS could acquire surface information effectively in getting the mass production of DEM and DOM. However, up to now most approaches are built upon single-wavelength Lidar system, which could only provide structure information of the vegetation canopy, the intensity information was rarely used to monitor vegetation growing state as its limitation on spectral characteristics. On the other hand, positive multi/hyper-spectral imaging instruments highly rely on the effects of weather, shadow and the background noise etc. The attempts to fuse single-wavelength Lidar data with multi/hyper-spectral data also been effected this way. Thus, a concept for a multi-wavelength, active canopy Lidar has been tested in this paper. The proposed instrument takes measurement at two vegetation-sensitive bands separately at 556 nm and 780 nm, which, according to the correlation analysis between the wavelengths and biochemical content with plenty of ground ASD reflectance dataset, showed a high correlation coefficient on the chlorophyll concentration as well as nitrogen content. The instrumentation of the multi-wavelength canopy Lidar employs low power, solid and semiconductor laser diodes as its laser source and the receiver consists of two channels, one for 556 nm back-scatter signal and the other for 780 nm. The system calibration has also been done by using a standard white board. Multi-wavelength back-scatter signals were collected from a scene consists of stones, healthy broad-leaf trees and unhealthy trees that suffer from disease(part of its leaves were yellow). It is shown that the multi-wavelength canopy Lidar could not only capture the structure information, but also could pick up the spectral characteristics. A further test of three dimensional reconstruction and SVM based classification were also done and the results showed that the spatial resolution could be as high as 5 mm and the accuracy of classification on those three features (woody/un-woody, healthy/unhealthy) reached to 86%. Therefore, the multi-wavelength canopy Lidar shows its potential capability on vegetation monitoring in a new effective way.

Hourly values of the critical frequency of the ionospheric F region, foF2, obtained at Chongqing ionospheric observatory (geographic 29.50N, 106.40E), China, during the interval of 1977 to 1997 (solar cycle 21 and 22) have been used to investigate the dependence of the monthly median foF2 on solar activity and geomagnetic activity, and to construct single-station model (SSM) using Fourier expansion. The results of the present analysis show that there is a significant nonlinear relationship between monthly median foF2 and sunspot number R especially at daytime in each month and nighttime in summer. Furthermore, introducing geomagnetic index Ap further improves the description of variation of monthly median foF2, and the standard deviations decrease also dependently on time and month. Thus the complex influence of solar activity and geomagnetic activity may be approximately expressed by a general multiple nonlinear function at Chongqing station, China. The basic aim of this paper is to show that considering the nonlinear influence both of solar activity and geomagnetic activity improves the monthly median model. The SSM is in good agreement with observations, with standard deviation 0.65MHz, while IRI model has a lower accuracy with standard deviation 0.96MHz.

Abstract The international GEOTRACES program has been instrumental in demonstrating how marine sediments are a critical source of dissolved Fe to the world's oceans. Here, we present dissolved iron (dFe) from the GEOTRACES North Pacific GP15 section, which, alongside other sediment‐source tracers (including dissolved δ56Fe, Mn, 228Ra, and particulate Fe), allows for identification of the dFe provenance of three distinct dFe depth maxima at the Alaskan margin. Two of these (shelf and abyssal depths) are of local Alaskan sedimentary origin. The third, a mid‐depth dFe maximum with an absence of 228Ra, is an advected signal that, based on tracer data from Western Pacific GEOTRACES transects and circulation models, must be advected from sedimentary sources on the Asian margin, ∼5,000 km away. This study illustrates the importance of measuring diagnostic sedimentary tracers like radium when assigning local margins as sedimentary sources of marine trace metal budgets.