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Accurate and internally coherent crop-yield forecasts are important for agricultural risk management, crop-insurance ratemaking, and regional risk assessment under climate variability. However, crop yields are influenced by high-dimensional and strongly correlated weather conditions, while forecasts produced at different spatial levels often violate aggregation constraints. Existing studies focus on yield prediction within individual regions and pay limited attention to weather-informed forecasting, hierarchical coherence, and insurance-oriented risk measurement. This paper develops an integrated framework for hierarchical crop-yield forecasting and risk assessment by combining dimensionality reduction for high-dimensional weather variables, probabilistic forecasting, and forecast reconciliation. Using county- and state-level spring and winter wheat yields in Montana from 1982 to 2022, we compare alternative base forecasting models and reconciliation methods under scenarios with and without weather information. Forecast performance is evaluated using point and probabilistic scoring rules, and the reconciled predictive distributions are used to construct scenario-based measures of downside yield risk. The results show that incorporating weather information and hierarchical reconciliation improves the quality and coherence of hierarchical yield forecasts. The resulting probabilistic forecasts provide a basis for loss-rate estimation, cross-county risk comparison, and spatial risk mapping and also support crop-insurance ratemaking under a retain–cede game between private insurers and the government.
An asymptotic theory is developed to investigate the interaction of surface water waves and a compressible muddy seabed in water of intermediate depth. The water column is treated as inviscid outside a thin bottom boundary layer, the thickness of which is assumed to be of the same order of magnitude as the wave amplitude. The seabed is modelled as an isotropic and homogeneous poro-viscoelastic layer with an incompressible solid skeleton and a compressible pore fluid. The thickness of the seabed is assumed to be comparable to the wave amplitude. Using a perturbation approach, the leading-order analytical solutions for the wave and mud flow are derived, while the evolution of the wave envelope, the mean Eulerian velocity and the mass transport velocity beneath progressive waves are obtained at the second order. Based on the present solution, the wave motion and the induced mass transport are analysed and compared with previous solutions that ignore the compressibility of the seabed. The results demonstrate that the compressibility of the seabed plays a critical role in modulating the flows within both the seabed and the overlying bottom boundary layer. Neglecting compressibility may lead to an underestimation of the interface vertical displacement in highly elastic beds and an overestimation in viscous-dominated cases. Consequently, the Reynolds stress distributions in these regions deviate significantly from predictions based on incompressible seabed theory. This inaccuracy further propagates to the prediction of second-order steady currents and mass transport velocities.
There are various types of nominal appositives. One is predicative, as in She invited Lulu Moppet, an old friend, to the party; one is specificational, as in She invited an old friend, Lulu Moppet, to the party; and a further type is equative, as in She invited Reginald Kenneth Dwight, Elton John, to the party. This paper argues that each type of nominal appositive comes from a reduced copular clause of a certain kind. Such a copular clause is base-generated as the complement of a categoryless functional head, like a low conjunct or a modifier. The combination of the reduced copular clause and the functional head is merged with, and categorized by, the matrix clause. Thus, a nominal appositive is not base-generated in the same proposition-denoting expression where its anchor occurs. Explicit steps of derivation for building a nominal appositive construction are proposed. The proposed syntactic derivations rule out unacceptable positions of nominal appositives. The research explores the general syntax of non-argument-taking relations.
The paper is trying to examine the changes between rational and irrational charitable donation of Chinese listed corporations under the background that an increasing number of Chinese listed corporations register charity foundations in recent years. Considering corporate income tax ratio as a proxy for tax preference, whether products are exposed to consumers directly or indirectly, as well as gross profit margin, debt financing scale and debt maturity structure as proxies for the reputation effect and strategic advantage, the indicators of rational charitable donation consist of the five factors mentioned above; The indicator of irrational charitable donation is disposal accrued profits calculated by Extended Jones Model. By the regression of data of charitable donations from Chinese A listed corporations during the year from 2008 to 2013, findings show that the behavior of rational charitable donation is weakened gradually, while, in contrast, the irrational charitable donation is strengthened. The listed corporations have strong motivation to transfer profits through registering and establishing charity foundations, which is a new tendency of transferring interests.
This paper aims to theorise how virtual reality (VR) can contribute to the development of contextual architecture. We start by considering how an architectural context may translate into a virtual domain, introducing preliminary definitions of what a virtual design context (VDC) could entail. We then discuss a proposed taxonomy that guides the creation of such a VDC, anchored in principles drawn from virtual realism in art philosophy and contextualism within architecture. This taxonomy is envisioned as a preliminary framework for developing VR-driven design environments with a focus on context. Next, we conducted expert user-testing with 24 architects using two VDCs developed according to the taxonomy. The goal of this step was to gain insights regarding the cognitive load of designers and their user experience while engaged in different types of VDCs. Results suggest that designing in these virtual environments enhanced contextual learning, supported conceptual and creative insight and helped maintain manageable cognitive load. The paper concludes by underscoring the real-world applicability of this taxonomy, highlighting how VR can breathe new life into contextual design, not by reducing context into a digital replica, but by opening new dimensions through which its richness can be explored, interpreted and reimagined.
Stress–velocity cross-spectra provide critical insights into the wall turbulence dynamics, where second-order cross-spectra have been used to characterise the amplitude modulation of large-scale motions on smaller scales. Here, we investigate the higher-order stress–velocity cross-spectra. Through theoretical analysis, we derive an exact relationship demonstrating that the difference in convection velocity between streamwise Reynolds normal stress fluctuations ($r$) and streamwise velocity fluctuations ($u$) – termed the $r{-}u$ convection velocity difference – is governed jointly by the second- and fourth-order cross-spectra. A new ‘coherence similarity’ (CS) model is proposed, which reveals an approximate similarity between higher-order and second-order cross-spectra. As a result, the $r{-}u$ convection velocity difference can be explained in terms of second-order cross-spectral properties. Numerical validation confirms that the CS model predicts higher-order cross-spectra and the convection velocity difference accurately. Furthermore, the contours of stress–velocity cross-spectra undergo a structural transition from single-lobe to triple-lobe patterns with increasing wall distance, suggesting the presence of complex space–time coupling between $r$ and $u$.
Kidneys are crucial for systemic lactate homeostasis, and a proper lactate balance subsequently supports normal kidney structure and function. The physiological lactate production-clearance axis along the proximal-distal tubular network may represent an important mechanism for maintaining tubulointerstitial microenvironmental balance. In the context of kidney diseases, the dynamic changes in lactate levels reveal the process of renal metabolic remodelling and even participate in the regulation of disease occurrence and progression.
Methods
This review systematically combs the maintenance of renal lactate homeostasis under physiological conditions and integrates current research findings on the roles of lactate in the initiation and progression of various kidney diseases, as well as the underlying core molecular mechanisms.
Results
Existing studies confirm that, in a variety of kidney diseases, abnormal lactate levels are closely associated with the occurrence of renal metabolic remodelling, and lactate itself can further regulate the progression of kidney diseases. Targeted regulation of lactate metabolism or lactate-related mechanisms of action is expected to provide a new perspective for the treatment of kidney diseases.
Conclusion
The exploration of lactate-related mechanisms offers potential insights for developing novel strategies for early diagnosis and therapeutic intervention of kidney diseases; however, more in-depth studies are still required to translate these findings into clinical practice.
To explore the longitudinal associations between a Chinese healthy diet and the progression of cardiometabolic multimorbidity (CMM) development among Chinese adults. A prospective analysis was conducted utilising data from 18 720 participants in the China Health and Nutrition Survey, spanning from 1997 to 2018. Dietary data were collected by three consecutive 24-h dietary recalls combined with the weighing method. A Chinese healthy diet score was developed by assigning scores to various food components. CMM was defined as the coexistence of two or more cardiometabolic diseases (CMD), including myocardial infarction, stroke and type 2 diabetes, diagnosed through blood indicators and clinical diagnosis. We employed a multistate model to examine the associations between the Chinese healthy diet and the longitudinal progression from being free of CMD to first CMD and then to CMM. Quantile G-computation was utilised to evaluate the relative contribution of each food component. Over a median follow-up period of 7·3 years, 2214 (11·8 %) participants developed first CMD, and 156 (0·83 %) progressed to CMM. Comparing participants in the highest quintile of dietary scores with those in the lowest, we observed a 55 % lower risk of transitioning from baseline to CMM (HR = 0·45, 95 % CI: 0·23, 0·87) and a 60 % lower risk of transition from first CMD to CMM (HR = 0·40, 95 % CI: 0·20, 0·81). Fresh fruits contributed to 42·8 and 43·0 % for delaying CMM and transition from first CMD to CMM, respectively. Our study revealed that greater adherence to the Chinese healthy diet is negatively associated with the risk of CMM.
It was found that a significant number of patients with major depressive disorder (MDD) did not respond to the treatment, leading to high ongoing costs and disease burden. The main objective of this study was to find neurobiological indicators that can predict the effectiveness of antidepressant treatment using diffusion tensor imaging (DTI). A group of 103 patients who were experiencing their first episode of MDD were included in the study. After 2 weeks of SSRI treatment, the group of patients was split into two categories: ineffectiveand effective. The FMRIB Software Library (FSL) was used for diffusion data preprocessing to obtain tensor-based parameters such as FA, MD, AD, and RD. Tract-Based Spatial Statistical (TBSS) voxel-wise statistical analysis of the tensor-based parameters was carried out using the TBSS procedure in FSL. We conducted an investigation to determine if there were notable variations in neuroimaging attributes among the three groups. Compared to HC, the effective group showed significantly higher AD and MD values in the left CgH. Correlating neuroimaging characteristics and clinical manifestations revealed a significant positive correlation between CgH-l FA and clinical 2-week HAMD-17 total scores and a significant positive correlation between CgH-r FA and clinical 2-week HAMD-17 total scores. Functional damage to the cingulum bundle in the hippocampal region may predispose patients to MDD and predict antidepressant treatment outcomes. More extensive multicenter investigations are necessary to validate these MRI findings that indicate treatment effectiveness and assess their potential significance in practical therapeutic decision-making.
The automation of assembly operations with industrial robots is pivotal in modern manufacturing, particularly for multispecies, low-volume, and customized production. Traditional programing methods are time-consuming and lack adaptability to complex, variable environments. Reinforcement learning-based assembly tasks have shown success in simulation environments, but face challenges like the simulation-to-reality gap and safety concerns when transferred to real-world applications. This article addresses these challenges by proposing a low-cost, image-segmentation-driven deep reinforcement learning strategy tailored for insertion tasks, such as the assembly of peg-in-hole components in satellite manufacturing, which involve extensive contact interactions. Our approach integrates visual and forces feedback into a prior dueling deep Q-network for insertion skill learning, enabling precise alignment of components. To bridge the simulation-to-reality gap, we transform the raw image input space into a canonical space based on image segmentation. Specifically, we employ a segmentation model based on U-net, pretrained in simulation and fine-tuned with real-world data, significantly reducing the need for labor-intensive real image segment labels. To handle the frequent contact inherent in peg-in-hole tasks, we integrated safety protections and impedance control into the training process, providing active compliance and reducing the risk of assembly failures. Our approach was evaluated in both simulated and real robotic environments, demonstrating robust performance in handling camera position errors and varying ambient light intensities and different lighting colors. Finally, the algorithm was validated in a real satellite assembly scenario, achieving a success rate of 15 out of 20 tests.
This study investigated the factors influencing the mental health of rural doctors in Hebei Province, to provide a basis for improving the mental health of rural doctors and enhancing the level of primary health care.
Background:
The aim of this study was to understand the mental health of rural doctors in Hebei Province, identify the factors that influence it, and propose ways to improve their psychological status and the level of medical service of rural doctors.
Methods:
Rural doctors from 11 cities in Hebei Province were randomly selected, and their basic characteristics and mental health status were surveyed via a structured questionnaire and the Symptom Checklist-90 (SCL-90). The differences between the SCL-90 scores of rural doctors in Hebei Province and the Chinese population norm, as well as the proportion of doctors with mental health problems, were compared. Logistic regression was used to analyse the factors that affect the mental health of rural doctors.
Results:
A total of 2593 valid questionnaires were received. The results of the study revealed several findings: the younger the rural doctors, the greater the incidence of mental health problems (OR = 0.792); female rural doctors were more likely to experience mental health issues than their male counterparts (OR = 0.789); rural doctors with disabilities and chronic diseases faced a significantly greater risk of mental health problems compared to healthy rural doctors (OR = 2.268); rural doctors with longer working hours have a greater incidence of mental health problems; and rural doctors with higher education backgrounds have a higher prevalence of somatization (OR = 1.203).
Conclusion:
Rural doctors who are younger, male, have been in medical service longer, have a chronic illness or disability, and have a high degree of education are at greater risk of developing mental health problems. Attention should be given to the mental health of the rural doctor population to improve primary health care services.
The Chinese pangolin Manis pentadactyla is categorized as Critically Endangered on the IUCN Red List, but the development of effective conservation strategies is hindered by a lack of data on its distribution range and population dynamics. In addition, standardized survey and analysis methods are required to facilitate the sharing of results and maximize conservation effectiveness. To fill these knowledge and methodological gaps, we investigated the occurrence of pangolin burrows in the subtropical forest ecosystem of Fujian, China. We surveyed a total of 70 transects across five land-cover types within the Fujian Junzifeng National Nature Reserve and detected 87 burrows. The majority of burrows (87%) were located in mixed conifer and broadleaf forests. We used six environmental variables in a generalized linear model to examine the relationship between the occurrence of burrows and environmental factors. The average model results from the best model set showed that the distribution of burrows was significantly influenced by forest type. For effective pangolin conservation, we recommend that local conservation authorities prioritize the protection of mixed conifer and broadleaf forests. Our findings support the local conservation of the Chinese pangolin and the standardization of surveys and conservation efforts across the species’ range.
We propose a B-integral management strategy for manipulating the nonlinear effects by employing a discrete single-crystal fiber (SCF) configuration, enabling direct amplification of 2-μm femtosecond pulses at high repetition rates without additional pulse picking, stretching and compression. The system delivers an average power of more than 56 W at 75.45 MHz with extremely high extraction efficiency (>55%) and near-diffraction-limited beam quality (M2 < 1.2). The dynamic evolution of the optical spectra and temporal properties in the power amplifier reveals that detrimental nonlinear effects are largely suppressed due to the low accumulated nonlinear phase shift in the discrete SCF layout. This straightforward, compact and relatively simple approach is expected to open a new route to the amplification of 2-μm ultrashort pulses at MHz and kHz repetition rates to achieve high average/peak powers, thereby offering exciting prospects for applications in modern nonlinear photonics.
In this article, we study an optimization problem for a couple including two breadwinners with uncertain life times. Both breadwinners need to choose the optimal strategies for consumption, investment, housing, and life insurance purchasing to maximize the utility. In this article, the prices of housing assets and investment risky assets are assumed to be correlated. These two breadwinners are considered to have dependent mortality rates to include the breaking heart effect. The method of copula functions is used to construct the joint survival functions of two breadwinners. The analytical solutions of optimal strategies can be achieved, and numerical results are demonstrated.
This study evaluated the effects of chenodeoxycholic acid (CDCA), a farnesoid X receptor (FXR) potential activator, on growth performance, antioxidant capacity, glucose metabolism and inflammation in largemouth bass (Micropterus salmoides) (initial body weight: 5·45 ± 0·02 g) fed a high-carbohydrate diet. Experimental diets included a positive control (5 % α-starch), a negative control (10 % α-starch) and two diets containing 10 % α-starch supplemented with either 0·05 % or 0·10 % CDCA. After 8 weeks, the high-carbohydrate diet reduced growth performance and increased hepatosomatic and viscerosomatic indexes, which were mitigated by 0·10 % CDCA supplementation. The high-carbohydrate diet also increased hepatic glycogen and crude lipid content, both of which were reduced by 0·10 % CDCA. Furthermore, the high-carbohydrate diet-induced oxidative stress, histopathological changes and reduced liver lysozyme activity, which were ameliorated by CDCA supplementation. Molecular analysis showed that the high-carbohydrate diet suppressed FXR and phosphorylated AKT1 (p-AKT1) protein expression in the liver, downregulated insulin signalling (ira, irs, pi3kr1 and akt1), gluconeogenesis (pepck and g6pc) and glycolysis genes (gk, pk and pfkl). CDCA supplementation upregulated fxr expression, activated shp, enhanced the expression of insulin signalling and glycolytic genes (gk, pk and pfkl) and inhibited gluconeogenesis. Additionally, CDCA reduced inflammatory markers (nf-κb and il-1β) and restored anti-inflammatory mediators (il-10, iκb and tgf-β). In conclusion, 0·10 % CDCA improved carbohydrate metabolism and alleviated liver inflammation in largemouth bass fed a high dietary carbohydrate, partially through FXR activation.
This paper provides an overview of the current status of ultrafast and ultra-intense lasers with peak powers exceeding 100 TW and examines the research activities in high-energy-density physics within China. Currently, 10 high-intensity lasers with powers over 100 TW are operational, and about 10 additional lasers are being constructed at various institutes and universities. These facilities operate either independently or are combined with one another, thereby offering substantial support for both Chinese and international research and development efforts in high-energy-density physics.
The Early-Middle Jurassic impression/compression macroflora and the palynoflora from the Qaidam Basin in the northeastern Qinghai-Xizang (Tibetan) Plateau have been well studied; however, fossil wood from this region has not been previously documented systematically. Here, we describe an anatomically well-preserved fossil wood specimen from the Lower Jurassic Huoshaoshan Formation at the Dameigou section in northern Qinghai Province, northwestern China. This fossil exhibits typical Metapodocarpoxylon Dupéron-Laudoueneix et Pons anatomy with usually araucarian radial tracheid pits and variable cross-field pits, representing a new record for Metapodocarpoxylon in the Qaidam Basin. This discovery indicates that trees with this type of wood anatomy were not confined to northern Gondwana but also grew in more northerly regions in Laurasia. The wood displays distinct growth rings, with abundant, well-formed earlywood and narrow latewood. This observation, along with previous interpretations based on macroflora, palynoflora and sedimentological data, suggests that a warm and humid climate with mild seasonality prevailed in the region during the Early Jurassic.
The ubiquitous marine radiocarbon reservoir effect (MRE) constrains the construction of reliable chronologies for marine sediments and the further comparison of paleoclimate records. Different reference values were suggested from various archives. However, it remains unclear how climate and MREs interact. Here we studied two pre-bomb corals from the Hainan Island and Xisha Island in the northern South China Sea (SCS), to examine the relationship between MRE and regional climate change. We find that the MRE from east of Hainan Island is mainly modulated by the Southern Asian Summer Monsoon-induced precipitation (with 11.4% contributed to seawater), rather than wind induced upwelling. In contrast, in the relatively open seawater of Xisha Island, the MRE is dominated by the East Asian Winter Monsoon, with relatively more negative (lower) ΔR values associated with high wind speeds, implying horizontal transport of seawater. The average SCS ΔR value relative to the Marine20 curve is –161±39 14C years. Our finding highlights the essential role of monsoon in regulating the MRE in the northern SCS, in particularly the tight bond between east Asian winter monsoon and regional MRE.