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Knowledge of the quantitative importance of the moisture transport pathways and mutual moisture exchange of the source regions of the Yangtze (SYZR) and Yellow (SYR) rivers' basins, the adjacent origins of China's two longest rivers, can provide insights into the regional atmospheric branch of the hydrological cycle over the source regions. The method with the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and a Lagrangian moisture source diagnostic to identify the major moisture transport pathways quantifies their importance to two types of daily precipitation events—daily precipitation more than 10 mm (PM) events and daily precipitation less than 10 mm (PL) events—for the two rivers' regions during the summer (June–August, 1986–2015) and finds the characteristics of mutual moisture exchange. The results indicated that both the Bay of Bengal group pathway and the northwest China group pathway play significant roles in PM and PL events over the SYZR, contributing 41.87% and 39.12% to PM events and 41.33% and 33.16% to PL events, respectively. The SYR has five main moisture path groups; the Bay of Bengal group pathway, the northwest China group pathway, and the southeast China group pathway play significant roles in PM and PL events over the SYR, contributing 32.34%, 23.28%, and 34.36% to PM events and 34.84%, 36.18%, and 19.83% to PL events, respectively. The volume of moisture passing from the SYZR to the SYR is approximately 60 times that of the reverse, constituting about 6.9% of the total moisture released in SYR precipitation. It is worth noting that the moisture release was concentrated in the nearer west group pathway, and the main moisture uptake locations were beyond the source region of the two rivers (remote sources) in the PM events. The aggregate moisture release high-frequency moisture transport path groups are found in the southeastern parts of Zhiduo County and the southeast of Zaduo County. [ABSTRACT FROM AUTHOR]

The study on the impact of consumer purchase intention on luxury goods has received widespread attention from the academic community. This study collected research data in Guilin, China, through questionnaire survey, and conducted an empirical study on the influencing factors of luxury consumers' purchase intention. The results show: The price level of luxury goods has a positive impact on consumers' face perception, while the positive impact of price level on expected regret has not been verified. Consumer's face perception has positive and negative effects on consumers' expected regret and consumers' purchase intention respectively. Consumer's downward expected regret and consumer's upward expected regret have different effects on consumers' purchase intention. Consumers' face perception and expected regret play a mediating effect in the research of influence relationship. This study is conducive to a better analysis of the psychology and behavior of Chinese luxury consumers, enriching the theoretical connotation of consumer psychology, and promoting the healthy development of the luxury goods industry. [ABSTRACT FROM AUTHOR]

The revisit intention of tourists is an important guarantee for the sustainable and healthy development of tourism destination, and has also received attention from the current academic community. However, there is still insufficient research on the antecedents of revisit intention from the perspectives of tourism destination, image and nostalgia emotion. This study takes China's ecological tourism scenic area (Guilin Lijiang Scenic Area) as a case study, and uses questionnaire survey method to obtain research data for empirical research. The results of this study confirm that tourism destination image has a positive impact on nostalgia emotions and local attachment, nostalgia emotion has a positive impact on local attachment, and local attachment has a positive impact on revisit intention. Perceived risk plays a negative moderating effect between local attachment and revisit intention. In addition, this study also examined the mediating effect of nostalgia emotion and local attachment. This study is beneficial for enriching the theory of the influence mechanism of revisit intention from the perspective of consumer psychology. It is an interdisciplinary research result of management and psychology, providing theoretical reference for improving revisit intention in tourism destinations and promoting their healthy development. [ABSTRACT FROM AUTHOR]

Biochar's underlying biochemical and physiological mechanisms in reducing irrigation and salinity stress are elusive. This paper investigates the effects of two types of biochar (wood biochar and poultry biochar) on the growth and physiology of tomato seedlings exposed to the combined effects of drought and salinity stress. Two types of biochar, wood biochar (WB) and poultry biochar (PB), were added to the soil separately, with three salinity gradients of 0, 100, and 200 mmol/L and two water supply conditions of full irrigation (FI) and deficit irrigation (DI). Results showed that biochar addition effectively improved the root water potential and osmotic potential of tomato plant under drought and salinity stress. Biochar application also mitigated leaf relative water content by 9.86% and 24.37% under drought and salinity stress, respectively. Furthermore, biochar application decreased abscisic acid concentrations in xylem sap under drought and salinity stress. Biochar altered the soil structure and increased field water holding capacity, indirectly increasing the soil water supply. While water use efficiency did not increase significantly after biochar application, a synergistic increase in seedling growth and water consumption occurred. In conclusion, biochar addition shows promise for promoting seedling growth to help mitigate the adverse impacts of drought and salinity stress on plant growth and physiology. [ABSTRACT FROM AUTHOR]

Climatological changes in rainfall affect the Tibetan Plateau's eco-hydrological processes and water resource regimes. To better understand these changes, we examined the historical and future changes in rain amount distribution (RAD) and rain frequency distribution (RFD) under Tibetan Plateau warming. Daily rain accumulation from two observed datasets (Climate Prediction Center and Climate Forecast System Reanalysis) and CMIP6 models under SSP126, SSP245, and SSP585 scenarios are used to estimate RAD and RFD at each grid point. To capture the full range of rainfall from light to heavy, we used logarithmically distributed rain-rate bins, whose coordinates enable mathematical operations. This means that each rain-rate bin is a percentage wider in log coordinates than the previous one, with the same bin center. Results showed that RAD magnitudes varied from 0.74 to 0.93 mm/day at moderate rain-rates, with the broadest and narrowest curves occurring in 2011–2020 and 1991–2000, respectively. These distributions changed strongly from moderate to heavier rain-rates at 2.8 mm/day/K. Furthermore, RFD magnitudes ranged from 13.03% (1991–2000) to 13.51% (2011–2020), with a negative response at light rain-rates (− 10.33%/K) and a positive response at moderate rain-rates (10%/K). Under future warming, RAD magnitudes were around 0.42 mm/day for the SSPs at moderate rain-rates, which shifted to heavier rain-rates, implying that the RAD curve will become larger with more rain at heavier rain-rates. Besides RAD whose response was around 2.85%/K under SSP126 at light rain-rate, most SSP126 responses were negative at light rain-rate but shifted positively and increased with SSP245 and SSP585 at heavier rain-rates. Overall, the rain distributions are moderately skewed and platykurtic, producing fewer and less extreme outliers than the normal distribution. Notably, there was no significant mean difference between the distributions; however, the change responses showed statistical differences (p < 0.05). This study will raise awareness of unexpected future events by showing how rain distribution changes with global warming. [ABSTRACT FROM AUTHOR]

[Display omitted] • 322 closed lake catchments are grouped by topography and land surface descriptors. • Similar physical geography and climatology may cause different lake area responses. • Precipitation controlled the inconsistent growth of lakes within the same cluster. • During strong evaporation periods, it is common to observe a decrease in lake area. • Precipitation, temperature, and glaciers change more dramatically after 2000. Naturally closed lakes located on the Tibetan Plateau provide a more authentic depiction of climate change and have undergone significant but dissimilar changes over the past four decades. Although previous research has concentrated on closed lake changes at regional and continental scales, the dominant factors related to closed lakes at the catchment scale remain elusive. This study employed the hierarchical minimum variance clustering method, six representative topographies and land surface descriptors to classify the catchments of 322 closed lakes (>1 km2) across the Tibetan Plateau from 1981 to 2020. To better understand the factors driving the changes in catchment-scale lake areas, we assigned two distinct attribute classes to the resulting classifications: hydro-meteorological characteristics and geographical environmental aspects. Our analysis revealed that five clusters are geographically coherent and exhibit distinct hydro-meteorological characteristics. By assessing decadal-scale changes in catchment characteristics over time for lakes in five clusters with area change of greater than ± 50 %, we found that the most significant driver of catchment changes from 1981 to 2000 was a continuous decline in snowmelt, followed by a substantial increase in precipitation, temperature, and glacial meltwater from 2000 to 2020. Regarding trends and magnitude, different lake area responses may occur in areas with similar physical geography and climatology (i.e., the same cluster). During the past four decades, only 3 % of lakes (19) shrank in area and decreased in change rate. Also, intense evaporation corresponds to a period of decrease in lake area. Despite the variation in lake area change among clusters, precipitation dominates the inconsistent increase in lake area under similar physical geography and climatology, with some exceptions strongly related to groundwater and melted permafrost recharge. Our findings have laid the groundwork for understanding this region's catchment characteristics and the resulting complex hydrological behavior. [ABSTRACT FROM AUTHOR]

The investigation of atmospheric characteristics is of great significance in properly exploiting air and water resources, and quantitatively estimating and nowcasting precipitation. Microwave radiometers are widely used in this field because they can operate unattended for a long time under almost all weather conditions, and obtain high-quality remote sensing data. This research focuses on the applications of ground-based microwave radiometers in retrieving meteorological characteristics of the Qinghai–Tibet Plateau (QTP) during the East Asian winter monsoon (EAWM), such as humidity and temperature structures, stability/convection indices, and cloud and precipitation retrievals. Vertical structures of atmospheric temperature, pressure, humidity, and other variables were investigated under clear-sky and snowy-sky conditions. The statistical characteristics of stability/convection indices in the QTP region, such as convective available potential energy (CAPE) and convective inhibition (CIN), were investigated, with a special focus on snowy-sky conditions. The relationship between potential cloud water resources and atmospheric and thermodynamics and instability conditions were taken into consideration. The results showed that the peak CAPEs under clear-sky and snowy-sky conditions were 1349.11 J/kg and 1165.12 J/kg, which were relatively larger than the corresponding values during the summer monsoon. CINs during the EAWM were small enough to be negligible. For quantitative precipitation forecasting (QPF), brightness temperatures at 30.0 GHz and 51.24 GHz sampling channels were sensitive to the snowfall process. Within 1 h before snowfall, the precipitable water vapour (PWV) and liquid water content (LWC) increased sharply by 0.05 cm and 0.12 mm, respectively, while the CAPE and downwards CAPE decreased by 225.60 J/kg and 180.31 J/kg, respectively. The findings of this article may be meaningful for characterizing meteorology and precipitation in the QTP and similar regions during the winter monsoon. [ABSTRACT FROM AUTHOR]

The final outcome of diabetes is chronic complications, of which vascular complications are the most serious, which is the main cause of death for diabetic patients and the direct cause of the increase in the cost of diabetes. Type 1 and type 2 diabetes are the main types of diabetes, and their pathogenesis is completely different. Type 1 diabetes is caused by genetics and immunity to destroy a large number of β cells, and insulin secretion is absolutely insufficient, which is more prone to microvascular complications. Type 2 diabetes is dominated by insulin resistance, leading to atherosclerosis, which is more likely to progress to macrovascular complications. This article explores the pathogenesis of two types of diabetes, analyzes the pathogenesis of different vascular complications, and tries to explain the different trends in the progression of different types of diabetes to vascular complications, in order to better prevent diabetes and its vascular complications. [ABSTRACT FROM AUTHOR]

The transport of atmospheric moisture presents a crucial role in the global hydrological cycle. In this paper, we performed an empirical orthogonal function (EOF) investigation of integrated moisture transport (IVT) which was observed to be connected with the renowned regional climate phenomenon named El Nino–Southern Oscillation (ENSO) in China. Results explained that in the Eastern and Southern China Sea, and Southeastern China, IVT variances were high, and could change significantly yearly. However, in Northern China, variances were quite low, meaning that monthly IVT was more predictable. The spatial distribution of IVT anomalies was different with the seasons. Summer, in particular, exhibited significantly higher IVT values across the equatorial western Pacific, and there was also a transfer of moisture from the tropical Indian Ocean to the Northwestern and Southeastern China. The primary six modes of the EOFs together explained about 52.3%, which accounted for greater than half of the variation in the IVT anomalies. The main mode was related to ENSO and it explained approximately 16.4% variance in the Southern China Sea and central equatorial Pacific, while the second mode illustrated about 10.8% variance and was strongest in the East China Sea and entire Southeastern China. The cross-wavelet coherence indicated that the IVT and ENSO time-series were coherent, having a duration of about 2–8 years. This thus implied that increased IVT was linked with enhanced ENSO activities. This study could contribute to a better perception of how atmospheric circulation patterns could modify the general flow of the atmosphere to affect normal weather conditions in China. [ABSTRACT FROM AUTHOR]

Acoustic agglomerations have increasingly attracted widespread attention as a cost-effective and environmentally friendly approach for fog removal and weather modification. In this study, research on precipitation interference and the agglomeration performance of droplet aerosols under large-scale acoustic waves was presented. In total, 49 field experiments in the source region of the Yellow River in the summer of 2019 were performed to reveal the influences of acoustic waves on precipitation, such as the radar reflectivity factor Z, rain rate R, and raindrop size distribution (DSD). A monitoring system that consisted of rain gauges and raindrop spectrometers was employed to monitor near-ground rainfall within a 5-km radius of the field site. The ground-based observations showed that acoustic waves could significantly affect the rainfall distribution and microstructure of precipitation particles. The average values of rainfall increased by 18.98%, 10.61%, and 8.74% within 2, 3, and 5 km, respectively, of the operation center with acoustic application. The changing trend of microphysical parameters of precipitation was roughly in line with variation of acoustic waves for stratiform cloud. Moreover, there was a good quadratic relationship between the spectral parameters λ and μ. Raindrop kinetic energy eK and the radar reflectivity factor Z both exhibited a power function relationship with R. [ABSTRACT FROM AUTHOR]

• A long short-term memory (LSTM)-based framework was developed for runoff projection. • Runoff over the Tibetan Plateau under different climate scenarios was projected at grid scale. • Future runoff represents an increase trend over the TP region. Runoff projections in the Tibetan Plateau (TP) can provide a valuable basis for making decisions regarding water resource management and facilitating the assessment of potential risks to water security. This study estimated the runoff of the Tibetan Plateau (TP) at a grid resolution of 0.5°for the near-term period (2022–2051) and the long-term period (2052–2082) under various climate scenarios. A framework based on long short-term memory (LSTM) was used to project the impact of climate change on runoff by integrating input selection, LSTM modelling and runoff projection application. This novel framework was used to determine the variables that contribute to runoff occurrence in different grid cells, analyze the relationship between these variables and runoff, and predict how runoff may change in the future due to precipitation, temperature, and antecedent runoff under various climate scenarios. The projected results showed that the runoff would be approximately 450 mm/a for the period from 2022 to 2051 and approximately 465 mm/a during the period from 2052 to 2082, representing an increase of about 46 % compared to the period from 1982 to 2012. Future runoff will increase in a decreasing pattern from the southwest to the northeast across the TP region. These findings regarding the projected increase in runoff will assist in the development of proactive adaptation strategies and support long-term economic growth through effective water resource management plans. [ABSTRACT FROM AUTHOR]

This study employs copula model to discuss joint relationship and design scenarios between precipitation (P), surface temperature (T), and precipitable water (PW) in seven regions and mainland China over 1980–2016 within a bivariate framework. Markov Chain Monte Carlo modeling in a Bayesian framework was applied to calculate copula parameters while best fitted copulas were assessed using Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), Root Mean Squared Error (RMSE), Nash‐Sutcliffe Efficiency (NSE), and maximum likelihood criteria. Results showed that the spatial variations of P decreased from South to Northwest, T decreased from South to North and from East to West. Distributions of P and T were similar, with higher values in regions c and d. PW was higher in the south, with more than 64.54 mm in the southwest, 25 mm in the north‐central. The correlation between PW and P as well as PW and T were higher than 0.74. Birnbaum Saunders distribution was considered appropriate to fit P in regions a and f while P and PW in other regions are good with Generalized Pareto. T performed better with generalized extreme in all regions. Moreover, Gumbel, Frank, and Joe copulas provided good fit for PW and P in regions b, f, and g, respectively while in regions a, c, d, and e, Nelson provided perfect fit. For PW and T, Nelson was a good fit in all regions. The bivariate probabilities and design scenarios in various regions suggest tremendous variations, with regions having high probabilities associated with low return periods. We showed that joint analysis of climate variables gives more robust design quantiles. Key Points: We present a framework for modeling the joint relationship between precipitation, temperature, and precipitable waterBirnbaum Saunders distribution was discovered for fitting precipitation in regions a and fWe estimated copula parameters using Markov Chain Monte Carlo simulation in a Bayesian framework [ABSTRACT FROM AUTHOR]

Atmospheric precipitable water (PW) is the basis of precipitation (P) formation, and the spatial difference between them is one of the focus of water resources research. Based on daily P from 552 meteorological stations and four reanalysis datasets during 1980–2016, the spatial–temporal pattern of PW and precipitation conversion rate (PWCR) in China are investigated using the whole layer atmospheric PW calculation formula, univariate linear regression, and inverse distance weighting. Results showed that ERA‐Interim reanalysis seems to match the magnitude and pattern of P over China with small regional differences. At daily scale, an increase (decrease) in P was connected with an increase (decrease) of PW in most regions, and the temporal change showed that PW was highest in summer and lowest in winter. Across China, the mean daily PW for CFSR, ERA‐Interim, JRA 55, and NCEP‐1 varied between 41.18–48.43 mm, 39.02–43.13 mm, 37.41–41.79 mm, and 43.06–48.33 mm, respectively in summer and between 11.67–13.79 mm, 10.21–11.87 mm, 9.96–11.83 mm, 11.92–13.73 mm in winter. The spatial pattern of PW showed increased moisture over the southwest, with a maximum positive trend of about 0.25 mm per day, particularly over the Tibet Plateau. Moreover, summer and autumn had the highest and lowest PWCR, respectively. During summer, PWCR for CFSR, ERA‐Interim, JRA 55 and NCEP‐1 ranged between 8.3–11.9%, 8.1–9.7%, 10.3–11.7% and 9.4–14.1%, while in autumn, 6.4–9.8%, 5.9–7.7%, 7.1–9.5%, and 8.1–12.3% were reported, respectively. Therefore, the potential of P arising from PW was great in summer. The PWCR had a declining trend from east to west and from south to north in space and the regional fluctuation was large, making the regional development potential of atmospheric water resources obvious. These results that lead to a better understanding of water vapour conversion over China will help to rationally develop and utilize atmospheric water resources. [ABSTRACT FROM AUTHOR]

• Acoustic agglomeration of liquid droplets in acoustic field is numerically studied. • The CFD-DEM model is validated against experimental data. • Effect of droplet fragmentation on acoustic agglomeration is investigated. • Effect of acoustic and granular parameters on aerosol agglomeration is analyzed. Acoustic agglomeration is widely considered a potentially effective technology for application in artificial defogging and precipitation. A coupled three-dimensional Computational Fluid Dynamics and Discrete Element Method (CFD-DEM) model was constructed to investigate the agglomeration performance of liquid droplets in the acoustic field. The acoustic field is calculated by solving the Linearized Navier-Stokes Equations (LNSEs) in the time domain, and the background flow is initially obtained using the Reynolds-averaged Navier-Stokes (RANS) equations with a k – ε turbulence model. The motion of the droplet aerosol follows Newton's second law with fluid-particle and particle-particle interactions, including collision, agglomeration, and fragmentation. The agglomeration performance of liquid droplets under high-intensity acoustic waves was numerically investigated in terms of the effects of the acoustic properties as well as the droplet characteristics. The numerical results show that it is necessary to consider droplet fragmentation in the process of acoustic agglomeration under the action of high-speed jet. The sprayed droplets are more likely to collide and condense than those without a breakup model, which has rarely been reported in previous studies. Acoustic frequency has a significant effect on agglomeration behavior, with optimal frequencies of about 225 Hz, 150 Hz, and 125 Hz corresponding to droplets with mode diameters of 15.97 μm, 25.85 μm, and 42.88 μm, respectively. However, despite the fact that most studies favoured large acoustic intensity for agglomeration performance, the agglomeration performance of aerosol particles is not always positively correlated with acoustic intensity, especially for large droplets. The optimal intensity of droplet with d p = 42.88 μm is in the range of 120-130 dB, which is smaller than the maximum operation pressure of 150 dB used in this study. In addition, an effective approach to increase the agglomerate size is to extend the residence time that liquid droplets are exposed in the acoustic and flow field, especially because the typical acoustic intensity of actual operation is usually not that high. [ABSTRACT FROM AUTHOR]

As a method for the effective removal of aerosol particles, acoustic agglomeration technology has been widely used in the field of dust removal and defogging. In this study, a coupled Computational Fluid Dynamics and Discrete Element Method model was developed to investigate acoustic agglomeration performance of aerosol droplets in a high-temperature and high-pressure environment. A four-way coupling strategy including flow-parcel and inter-parcel interactions was fully considered. A simple parcel-parcel interaction model was introduced with an elastic coefficient calibrated as 1 × 10−14 kg·s−2. A comprehensive investigation focused on determination of the agglomeration characteristics of droplet aerosols under the action of acoustic waves. The acoustic wave significantly influences the agglomeration behavior of aerosol droplets by changing the acoustic pressure structure in an agglomeration chamber and changing the acoustophoretic force exerted on the droplet. The environmental parameters of operating pressure and ambient temperature indirectly affect the interaction processes of transient flow and aerosol droplets. In general, the results showed better aerosol agglomeration performance in high-temperature and high-pressure environments. Unlabelled Image • Aerosol dynamics with and without sound application is conducted. • Effect of operating pressure on acoustic agglomeration is investigated. • Effect of temperature on acoustic agglomeration is investigated. • Effect of interaction between droplets on acoustic agglomeration is analyzed. • Agglomeration efficiency of water mist in acoustic field is numerically studied. [ABSTRACT FROM AUTHOR]

Ventilated roofs can improve thermal performance and reduce the energy consumption of building roofs. In this study, the optimal design parameters and adaptability of naturally ventilated roofs were determined through numerical investigations of the effects of different influencing factors on their thermal performance. A three-field coupling numerical simulation method considering temperature, flow, and solar radiation fields was used to improve simulation accuracy. The research results show that the optimal air gap layer thickness of a naturally ventilated roof increases with increasing roof length, which has not been considered in previous studies. The peak interior surface temperature of the ventilated roof increases with increasing outdoor atmospheric pressure. Ventilated roofs with a 30°–40° slope have a stronger stack effect and can better discharge solar heat gains when compared to roofs with other slopes. Interior surface temperature is reduced when phase change materials is set in the upper rather than the lower roof during summer. Phase change materials should be set in the upper roof to save energy. Small damage holes in the upper roof don't apparently affect the ventilated roof thermal performance. The findings of this study can guide optimization design and help evaluate the energy-saving effects of naturally ventilated roofs. • A three-field coupling simulation method is proposed to improve simulation accuracy. • Effect of roof length on thermal performance of ventilated roof is investigated. • Effect of atmospheric pressure on thermal performance of ventilated roof is studied. • Effects of CPCM and damage hole on thermal performance of ventilated roof are studied. • Optimum design parameters of naturally ventilated roofs are presented. [ABSTRACT FROM AUTHOR]

A weakly compressible smoothed particle hydrodynamics (WCSPH) method was developed to model open-channel flow over rough bed. An improved boundary treatment is proposed to quantitatively characterize bed roughness based on the ghost boundary particles (GBPs). In this model, the velocities of GBPs are explicitly calculated by using evolutionary polynomial regression with a multiobjective genetic algorithm. The simulation results show that the proposed boundary treatment can well reflect the influence of wall roughness on the vertical flow structure. A fully developed open channel is established, and its flume length, processing time, and turbulent model are discussed. The mixed-length-based subparticle scale (SPS) turbulence model is adopted to simulate uniform flow in open channel, and this model is compared with the Smagorinsky-based one. For the modified WCSPH model, the results show that the calculated vertical velocity and turbulent shear stress distribution are in good agreement with experimental data and fit better than the calculations obtained from the traditional Smagorinsky-based model. [ABSTRACT FROM AUTHOR]

[Display omitted] • The theoretical analysis is applied to investigate acoustic agglomeration of aerosol particle. • Droplet agglomeration induced by acoustic waves and turbulent flow is considered. • The probability of collision and agglomeration of particles is investigated. • The rapid refilling process of aerosols after an orthokinetic motion is considered. • Effects of environmental parameters on aerosol agglomeration are conducted. This study meticulously explores the agglomeration mechanisms in microscale droplet aerosols, specifically focusing on acoustic and turbulent agglomeration mechanisms. Our theoretical analysis reveals a significant impact of orthokinetic and hydrodynamic processes on acoustic agglomeration. The acoustic wake effect elucidates the swift replenishment of small particles subsequent to an orthokinetic phase. An optimal frequency, varying for different droplets, was identified in orthokinetic agglomeration within the 50–250 Hz range. Hydrodynamic agglomeration remained relatively stable at an acoustic frequency exceeding 1000 Hz. The aggregation kernel function, denoted as K ij , exhibited a significant increase with increasing sound pressure levels, reaching up to 10−8 s−1. Environmental temperature had a predominantly positive effect on orthokinetic and Brownian agglomeration, although it exhibited an inhibitory effect on hydrodynamic agglomeration. For raindrops, a correlation was identified between particle spacing and K ij ; a larger particle spacing corresponded to a smaller K ij. Despite an increase in particle spacing to 50 times the particle diameter, the hydrodynamic effect persisted. The aggregation kernel function linked to Brownian thermal motion was found to be 3–4 orders of magnitude lower than that of orthokinetic and hydrodynamic interactions. Additionally, the turbulent agglomeration kernel function for fog, cloud, and rain droplets with corresponding parent nuclei of 100 μm was of the same order of magnitude as the acoustic agglomeration kernel function. [ABSTRACT FROM AUTHOR]

In this paper, an efficient proposal for quantum controlled teleporatation of arbitrary multi-qubit states is presented via three-qubit non-maximally entangled states. The successful probability is viewed as one of the most important performance parameters for quantum teleportation. The significant advantage of our scheme is that the successful probability is independent of the coefficients of partially entangled states, and is always equal to 100% in spite of using non-maximally quantum channel. From the concrete implementation processes of this proposal, it could be found that only the usual Bell-state measurement, simple single-qubit projective measurement and common single-qubit local unitary operations, of which the physical realization has been widely explored, need to be performed without the introduction of auxiliary particles. [ABSTRACT FROM AUTHOR]

An efficient scheme for controlled dense coding is presented with the aid of the introduction of auxiliary particles, appropriate local unitary operations and measurement basis. In this proposal, the four-qubits maximal slice state, which belongs to partially entangled states, is used as quantum channel. The concrete implementation procedures for our scheme with one sender, one receiver and two controllers are given in detail, and the average transmitted classical information from the sender to the receiver is calculated. Additionally, the physical realization of this proposal is discussed based on the optical elements. [ABSTRACT FROM AUTHOR]

In this paper, an efficient scheme for controlled dense coding is presented via partially entangled states with the aid of auxiliary particles and appropriate local unitary operations. The detail implementation producers for our proposal are given, and the total average amount of classical information, which is depending on the superposition factors of quantum channel and measurement basis of the controller, is calculated. Moreover, it is demonstrated that this proposal can be realizable based on quantum circuits. [ABSTRACT FROM AUTHOR]

We propose a novel and efficient scheme for probabilistic controlled remote state preparation of an arbitrary two-qubit quantum state with the aid of the introduction of auxiliary particles and some appropriate local unitary operations. In this scheme, two partially three-qubit entangled states are used as quantum channel. The controlled preparation with one sender, two receivers and one controller can be realized when the information of nonmaximally entangled states are only available for the sender. Furthermore, the concrete implementation processes of this proposal are presented, and the successful probability of our scheme are calculated in the general case and special case, respectively. [ABSTRACT FROM AUTHOR]

In most parts of China, water resources development and utilization has reached or exceeded the international warning level, especially in the northern arid and semi-arid regions, the serious water stress have aroused worldwide concerns. Many issues of water resources are closely and some inseparably associated with human activities. In this study, the water footprint (WF) and related indicators were applied as comprehensive indicators to assess real water use by humans from the consumption perspective. A Fuzzy Comprehensive Evaluation Model (FCE) was used for the evaluation in its role to assess water stress. And the index system of water stress assessment including four aspects, namely water supply and demand balance, socio-economy, agricultural production and ecological environment was established. Taking the case of Hebei province of China where there is serious conflict between water supply and demand, water stress assessment of all eleven administrative areas for the period 2000–2013 was analyzed. The findings showed that water stress was denoted by three levels, namely high water stress (red zone), general water stress (yellow zone) and low water stress (blue zone), which lays the foundation of the further research on water risk warning. According to the results of water stress assessment and the socio-economic development trends of Hebei, a Markov Chain Risk Warning model was built to describe the risk state of water system and to predict the transition probability of future states. This was intended to focus on the possibility that water stress levels might change into higher water stress level. The current study aims at extending earlier research by making a first step from water footprint estimation towards water stress assessment and providing reference for scientific management of water resources in arid and semi-arid regions. [ABSTRACT FROM AUTHOR]

• Most of the extreme precipitation events (EPEs) occurred within the southern foothills of the Tibetan Plateau (TP) • Climatology of integrated moisture transport and precipitation conversion efficiency during EPEs were evaluated. • Moisture for EPEs primarily originated from the Arabian sea, Bay of Bengal, Indian landmass areas, and local moisture within the TP. • Results obtained from PSCF and CWT shared similar characteristics, demonstrating the potential moisture source areas effectively. Understanding moisture sources and transport mechanisms during extreme precipitation events (EPEs) is imperative for sustainable development. Here, potential moisture sources, contributions, and transport pathways were evaluated during EPEs over Tibet Plateau (TP) between 1951 and 2015, employing three back-trajectory approaches, including Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT), Potential Source Contribution Function (PSCF), and Concentration Weighted Trajectory (CWT). Results showed that all twenty-three selected EPEs occurred within the TP's southern foothill. Back-trajectories from the EPEs target are then clustered into five, and analysis revealed that moisture sources and pathways showed a similar pattern. Generally, moisture largely originates from three sources, including airflow trajectories from the Arabian Sea, Bay of Bengal, and tropical-subtropical area of the Indian landmass. Besides, local moisture transport within TP also has key influences. For instance, analysis from the first EPEs target showed southwesterly (Cluster 1; 12 %, Cluster 2; 20 %, Cluster 3; 22 %) and southeasterly (Cluster 4; 30 %, Cluster 5; 16 %) moisture paths originating from the Arabian Sea and Northern India, respectively. Moisture transport (IVT) path analysis for this target showed that all IVT clusters in descending order were 3 > 4 > 2 > 5 > 1, with a mean of 243 kg/m/s. Conversely, above-average IVT clusters ranged from 305 to 345 kg/m/s and had a mean of 334 kg/m/s, while cluster 2 had the highest contribution of 37 %. Moisture transport source regions obtained utilizing PSCF and CWT methods naturally share comparable features, proving the credibility and accuracy of the results. Based on the EPEs and back-trajectory analysis in this study, we demonstrated unique moisture sources and dominant moisture pathways for each EPEs target. This is important in modeling, simulating, and predicting extremes in space and time and, consequently, for resource management. This may also aid in mitigating numerous natural disasters arising from EPEs and provide significant scientific references for coordinated atmospheric research. [ABSTRACT FROM AUTHOR]

In this paper, we put forward two novel schemes for probabilistic remote preparation of an arbitrary quantum state with the aid of appropriate local unitary operations when the sender and the receiver only have partial information of non-maximally entangled state, respectively. The concrete implementation procedures of the novel proposals are given in detail. Additionally, the physical realizations of our proposals are discussed based on the linear optics. Because of that neither the sender nor the receiver need to know fully the information of the partially entangled state, our schemes are useful to not only expand the application range of quantum entanglement, but also enlarge the research field of probabilistic remote state preparation (RSP). [ABSTRACT FROM AUTHOR]

Atmospheric rivers (ARs) have been reported to be related to Extreme Precipitation Events (EPEs). Hence, we made an assessment in the Yangtze River Basin (YRB) to understand the nexus between EPEs and ARs since the YRB has frequently encountered flooding. We threshold 6-hly fields of ERA-Interim Integrated Vapor Transport (IVT) based on the 85th percentile and a lower limit of 100 kg/m/s, and check for geometry requirements and other considerations indicative of ARs conditions. Large-scale climate modes were used to examine linkages between the frequency of ARs and the atmospheric circulation system. We recorded 75 EPEs for all 16 heavy precipitation-related flood events that occurred on days when precipitation exceeded 95% of the 3-day moving average from 1985 to 2019. Further, huge moisture transport amounts between 500 and 1000 kg/m/s were recorded some days before these identified events. Consequently, 14,347 ARs were identified, and the statistics showed that the length, width, length-width ratio, IVT, and coherent in IVT direction had medians of 3733 km, 615 km, 6.39, 350 kg/m/s, and 0.89, respectively. During most of the flood events, ARs frequencies were relatively high, with about 24% making landfall on YRB. Moreover, the deviance between the entire mean and mean composites during ARs days for the selected events in their respective study periods were in the range of 1.00–2.37 mm and 10–75 kg/m/s for precipitation and IVT, respectively, which could have resulted in the observed flood events. The positive tendencies of the NINO 3.4 and MeiV.2 indices enhanced ARs activities, thereby leading to more extreme events. The ARs distribution and associated impacts indicate a significant role of ARs in shaping the global hydrological cycle. These results could further bridge the gap to more robust hydrometeorological studies in China. • Sixteen extreme precipitation-related flood events were observed over YRB. • Seventy-three persistent ARs made frequent landfall during the summer flood events. • ARs frequencies were higher than 24% during the occurrence of the flood events. • ARs contribute substantially to the flood events over YRB, and could be enhanced by ENSO activities. [ABSTRACT FROM AUTHOR]

We propose two novel schemes for probabilistic remote preparation of an arbitrary quantum state with the aid of the introduction of auxiliary particles and appropriate local unitary operations. The first new proposal could be used to improve the total successful probability of the remote preparation of a general quantum state, and the successful probability is twice as much as the one of the preceding schemes. Meanwhile, one can make use of the second proposal to realize the remote state preparation when the information of the partially entangled state is only available for the sender. This is in contrast to the fact that the receiver must know the non-maximally entangled state in previous typical schemes. Hence, our second proposal could enlarge the applied range of probabilistic remote state preparation. Additionally, we will illustrate how to combine these novel proposals in detail, and our results show that the union has the advantages of both schemes. Of course, our protocols are implemented at the cost of the increased complexity of the practical realizations. [ABSTRACT FROM AUTHOR]

Highlights: [•] We estimate RAM requirements for multi-reservoir dynamic programming (DP) problems. [•] We parallelize DP considering distributed computing and distributed computer memory. [•] The parallel DP algorithm is efficient, scalable and practical. [•] The parallel DP algorithm solves previously unsolvable multi-reservoir DP problems. [ABSTRACT FROM AUTHOR]

Low-frequency acoustic interference in clouds can be regarded as a potential artificial precipitation technology in extreme environmental conditions such as the plateau with low temperature and oxygen content, particularly those areas with altitudes above 4000 m. In this study, 49 field tests were performed in the source region of the Yellow River (SRYR) during the East-Asian summer monsoon to reveal the influence of strong acoustic interference on cloud and precipitation, including the radar reflectivity factor (Z), liquid water content (L wc), and rain rate (R). Research on precipitation interference and rainfall microphysical results under large-scale acoustic waves were investigated in detail via Ka cloud and KaKu weather radars. Ground-based observations showed that Z , L wc , and R values were sensitive to acoustic application, especially for stratiform clouds. The effects of acoustic intervention were found to be weakened by severe acoustic attenuation near sampling altitudes of 1200 m. The Z -value difference ranged from −4.18 to −0.31 dBZ for stratiform rain during the East-Asian summer monsoon of the Darlag region of China. The differences in Z , L wc , and R between operating and monitoring periods of rainfall samples overall decreased with increased height. The average values of L wc and R with acoustic applications below 1800 m were 0.12 g·m−3 and 2.42 mm·h−1 stronger than that above 1800 m, respectively. • Field tests were performed to reveal the effect of acoustic interference on clouds. • Precipitation microphysical results were investigated via Ka and KaKu radars. • Precipitation process in the source region of the Yellow River (SRYR) was investigated. • Inversion methods of clouds and precipitation in SRYR were investigated. [ABSTRACT FROM AUTHOR]

Acoustics can cause particles/droplets to agglomerate in the air medium, thereby accelerating gravity sedimentation. To assess the microphysical characteristics and environmental isotope effects of micro-droplet groups under the action of acoustic waves, an air chamber experimental platform was established, and 100 groups of controlled experiments were conducted. The characteristic particle size, size spectrum, isotope values, corresponding linear relationships with hydrogen and oxygen, and d values were analyzed. The isotope exchange equation between the micro-droplet groups and environmental water vapor inside the air chamber was investigated. The results showed that the peak size values of the micro-droplet groups increased under the action of acoustic waves. The characteristic particle size (D90) showed a "trigger effect" with the acoustic operation with a positive deviation in the size spectrum and isotope exchange between the micro-droplet groups and environmental water vapor. The relative variations in theoretical values for different sedimentation conditions were consistent with those of the experimental results. Environment isotopes could be used to trace the acoustic agglomeration process of micro-droplets in the future. [ABSTRACT FROM AUTHOR]

The pancreatic duodenum homeobox-1 (PDX-1) is a transcription factor encoded by a Hox-like homeodomain gene that plays a crucial role in pancreatic development, β-cell differentiation, and the maintenance of mature β-cell functions. Research on the relationship between PDX-1 and diabetes has gained much attention because of the increasing prevalence of diabetes melitus (DM). Recent studies have shown that the overexpression of PDX-1 regulates pancreatic development and promotes β-cell differentiation and insulin secretion. It also plays a vital role in cell remodeling, gene editing, and drug development. Conversely, the absence of PDX-1 increases susceptibility to DM. Therefore, in this review, we summarized the role of PDX-1 in pancreatic development and the pathogenesis of DM. A better understanding of PDX-1 will deepen our knowledge of the pathophysiology of DM and provide a scientific basis for exploring PDX-1 as a potential target for treating diabetes. [ABSTRACT FROM AUTHOR]

With the advent of the internet era, wearable electronic devices and flexible electronic technology are rapidly emerging, and new resistive random access memory (RRAM) based on flexible substrates have thus gained extensive attention. Here, the flexible Bi 0·95 Er 0·05 FeO 3 /ZnO/La 0·66 Sr 0·34 MnO 3 (BEFO/ZnO/LSMO) heterostructure is prepared on Mica substrate using the sol-gel method. The high resistance state (HRS) to low resistance state (LRS) ratio consistently surpasses 102 under the flat and the 15 mm bending radius state. There is no significant change in the resistive switching (RS) behavior after 30 I–V curve cycles and 103 write/erase operations on the BEFO/ZnO/LSMO heterostructure, which reflects excellent stability. In addition, the device still works properly at 175 °C for dynamic conversion between HRS and LRS. The observed RS behavior in the BEFO/ZnO/LSMO heterostructure is attributed to ion migration and alterations in the potential barrier height at the interfaces. These results suggest that the BEFO/ZnO/LSMO heterostructure based on a flexible Mica substrate plays a crucial role in the development of next-generation portable and flexible electronic systems due to its excellent flexibility and thermal stability. [ABSTRACT FROM AUTHOR]

Understanding the risks of planktonic algal proliferation and its environmental causes is crucial for protecting water quality and controlling ecological risks. Reservoirs, due to the characteristics of slow flow rates and long hydraulic retention times, are more prone to eutrophication and algal proliferation. Chlorophyll-a (Chl-a) serves as an indicator of planktonic algal biomass. Exploring the intricate interactions and driving mechanisms between Chl-a and the water environment, and the potential risks of algal blooms, is crucial for ensuring the ecological safety of reservoirs and the health of water users. This study focused on the Danjiangkou Reservoir (DJKR), the core water source of the Middle Route of the South-to-North Water Diversion Project of China (MRSNWDPC). The multivariate statistical methods and structural equation modeling were used to explore the relationships between chlorophyll-a (Chl-a) contents and water quality factors and understand the driving mechanisms affecting Chl-a variations. The Copula function and Bayesian theory were combined to analyze the risk of changes in Chl-a concentrations at Taocha (TC) station, which is the core water source intake point of the MRSNWDPC. The results showed that the factors driving planktonic algal proliferation were spatially heterogeneous. The main factors affecting Chl-a concentrations in Dan Reservoir (DR) were water physicochemical factors (water temperature, dissolved oxygen, pH value, and turbidity) with a total contribution rate of 60.18%, whereas those in Han Reservoir (HR) were nutrient factors (total nitrogen, total phosphorus, and ammonia nitrogen) with a total contribution rate of 73.58%. In TC, the main factors were water physicochemical factors (turbidity, pH, and water temperature) and nutrient factors (total phosphorus) with total contribution rates of 39.76% and 45.78%, respectively. When Chl-a concentrations in other areas of the DJKR ranged from the minimum to the uppermost quartile, the probabilities that Chl-a concentrations at the TC station exceeded 3.4 μg/L (the benchmark value of Chl-a for lakes in the central-eastern lake area of China) owing to the influence of these areas were all less than 10%. Thus, the risk of planktonic algal proliferation at the MRSNWDPC intake point is low. This study developed an integrated framework to investigate spatiotemporal changes in algal proliferation and their driving factors in reservoirs, which can be used to support water quality management in mega hydro projects. [ABSTRACT FROM AUTHOR]

The characteristics of plateau precipitation and atmosphere, once accurately and comprehensively understood, can be used to inform sound air–water resource development practices. In this study, atmospheric exploration of the Tibet Plateau (TP) was conducted using ground-based microwave radiometer (MWR) data collected during the East Asian summer monsoon. Atmospheric temperature, pressure, humidity, and other variables were gathered under clear-sky, cloudy-sky, and rainy-sky conditions. Statistical characteristics of the air parcel height and stability/convection indices such as convective available potential energy (CAPE) and convective inhibition (CIN) were investigated, with a special focus on the rainy-sky condition. Two retrieval applications for characterizing precipitation, namely short-term precipitation forecast and quantitative precipitation estimation were presented. Results showed that CAPE values in the Darlag region reached extremes around 18:00–20:00 (UTC+8) for cloudy-sky and rainy-sky conditions with corresponding peaks of about 1046.56 J/kg and 703.02 J/kg, respectively. When stratiform or convective–mixed precipitation occurs, the precipitable water vapor (PWV) and CAPE values were generally greater than 1.7 cm and 1000 J/kg, respectively. CAPE values are likely to decrease before the occurrence of precipitation due to the release of the latent heat in the atmosphere. [ABSTRACT FROM AUTHOR]

• A new integrated framework for daily streamflow forecasting is developed. • Data classification and input selection leads to improved performance. • Structure validation based on understanding of physical systems leads to more confident results. Data-driven models can achieve high accuracy and low computational cost without a priori knowledge of hydrological system, which have been successfully applied in streamflow forecasting for decades. However, it is still a challenging task to improve the performance of these models, especially for the rivers with dramatic flow changes. In this paper, a new integrated framework for daily streamflow forecasting based on different flow regimes is developed. The framework integrates a Fuzzy C-means (FCM) clustering for streamflow regime identification, a partial mutual information (PMI) for input selection, Deep Belief Networks (DBN) for mapping the nonlinear relationships between the selected inputs and streamflow during different streamflow dynamics processes, and a rigorous validation process considering structure validity to interpret the physical processes simulated using the DBN models. The framework was applied to three streamflow stations with different climate conditions in USA, and the results show that the framework has significantly improved modelling performance (approximately 12%) compared to single data-driven models. The integration of data-driven models and physical process classification also leads to improved integration of physical understanding of the complex characteristic of different flow regimes into the modelling process, leading to overall improved confidence in the developed daily streamflow forecasting models. [ABSTRACT FROM AUTHOR]

As a potentially effective technology for particle removal, acoustic agglomeration technology has been tested for airport defogging and weather modification. Small-scale experiments and simulation studies have shown that acoustic waves can accelerate agglomeration of droplets and aerosol particles, but this has not been confirmed by large-scale field experiments and observations. In this study, field experiments were conducted in a high-altitude and non-interference environment to investigate cloud and precipitation interference by low-frequency acoustic waves. Field tests were carried out in the source region of the Yellow River (SRYR) from July 21, 2019 to November 20, 2019. Macro- and micro- physical characteristics of cloud and precipitation in stratiform and convective–mixed precipitation systems were monitored by disdrometer, micro rain radar, and microwave radiometer. The results showed sensitivity of microphysical parameters of rain rate (R), radar reflectivity factor (Z), liquid water content (L wc) and height of cloud base (H c) to acoustic operation. Of these, values of R , Z, and L wc became larger under the action of acoustic waves, and H c values became lower with acoustic operation. Spectral parameters λ against μ , Z against R , and L wc against R at different sampling altitudes and for different precipitation systems follow a quadratic function, power function, and linear function, respectively. The results of this study should be instructive for further efforts to investigate and develop atmospheric interference technology with low-frequency strong acoustic waves. • Field tests were conducted to investigate acoustic interference on rainfall. • Vertical microphysical characteristics of precipitation were investigated. • Precipitation process in the source region of the Yellow River was investigated. • Quantitative precipitation estimation with acoustic operation was performed. • Characteristics of stratiform and convective precipitations were compared. [ABSTRACT FROM AUTHOR]

Quantum direct communication (QDC) uses the basic principle of quantum mechanics to realize the secure communication between legal parties. Deterministic secure quantum communication (DSQC), as a branch of QDC, is a way to transmit secret message with the aid of classical bits. In this paper, a multi-party DSQC based on d -dimension k -particles GHZ states is proposed, in which unitary operation is not required. On the basis of d -dimension single-photon measurement results, the communication parties encode and decode the message through performing modulo addition and subtraction. In addition, the scheme uses the added d -dimension single photon for eavesdropping detection. The scheme has expansibility and universality. It can scale to as many parties in any dimension as required. Based on the star-shaped communication structure, it can be extended to a network to achieve the rapid communication of secret message across regions. [ABSTRACT FROM AUTHOR]

• The LASSO-FCM-DBN approach can improve the performance of streamflow prediction. • The performance of the FCM classification is more stable than the threshold method. • DBNs performed better than traditional ANNs in all three statistical measures considered. Streamflow prediction is a challenging task due to the different processes involved in streamflow generation. These different processes have different characteristics of the relationships between hydro-meteorological variables and streamflow, which make it a challenging task to develop single data-driven stream flow prediction models that can map the input-output relationships for all different streamflow regimes. To improve the performance of streamflow prediction, we proposed a flow-regime-dependent approach to map the relationships between hydro-meteorological variables and streamflow based on hydro-meteorological condition classification. This approach integrates the least absolute shrinkage and selection operator (LASSO), Fuzzy C-means (FCM) and Deep Belief Networks (DBN) and therefore referred to as the LASSO-FCM-DBN approach. This approach employs LASSO to select the hydro-meteorological variables which have a significant impact on streamflow, FCM to identify different streamflow regimes, and DBN as a data-driven model to map the nonlinear and complex relationships between the selected hydro-meteorological variables and streamflow within different flow regimes. To assess the performance of the proposed approach, two comparative studies were carried out – 1) the multi-variable FCM was compared to the traditional single-variable threshold-based method; and 2) the performance of the DBN was compared to a traditional Artificial Neural Networks (ANNs) model. Two stations in the Tennessee River, USA were used as the case study. The results demonstrate that the performance of the multi-variable-based FCM classification method is better and more stable than the traditional threshold-based single-variable method, due to the sensitivity of the single-variable method to different threshold values. In addition, DBNs performed better than traditional ANNs in all three statistical measures considered. Overall, the LASSO-FCM-DBN multi-model system significantly improved the performance of streamflow prediction and is therefore a valuable tool for water resources management and planning. [ABSTRACT FROM AUTHOR]

It is necessary to comprehensively understand the hydro-dynamic behavior of spilled oil contained by the floating oil boom, especially for emergency response after an oil spill accident. In the present study, the profile evolution process and principal containment failure mechanism of moderate-viscous oil in wave-current coupling condition are experimentally investigated by considering the effects of the oil viscosity and the spilled volume as well as the boom characteristics of material stiffness, skirt length and buoyancy-weight ratio. A series of empirical formulae in terms of slick length, peak thickness as well vortex scale near the boom, initial failure velocity and loss rate of spilled oil considering the oil properties, the spilled volumes and boom characteristics are proposed using a non-linear global stepwise regression method, namely evolutionary polynomial regression technique with multi-objective genetic algorithm. In addition, protective measures are proposed to reduce the loss of oil spill. [ABSTRACT FROM AUTHOR]

• A physically-based drought index (SZI) was appraised for regional drought monitoring. • SZI is more reliable in monitoring multi-category and multi-scalar drought senecios. • CAFEC precipitation is more reliable than PET in estimating Atmospheric water demand. • SZI performs much better than SPEI and ScPDSI in both humid and non-humid regions. The uncertainties in atmospheric water demand used in evaluating drought indices are the primary cause of discrepancies between them, especially in water-limited regions. This study evaluated Standardized Moisture Anomaly Index (SZI) using a combined water-energy balance approach, and compared the performance with the Standardized Precipitation Evapotranspiration Index (SPEI) and self-calibrated Palmer Drought Severity Index (ScPDSI) over seven climatic regions in China from 1948 to 2017. The atmospheric water demand in SZI is evaluated using climatically appropriate precipitation for existing conditions (CAFEC) , which takes into account most parts of the surface water-energy balance (i.e., precipitation, evapotranspiration, runoff, and soil moisture recharge and loss). The relative performances of SZI , SPEI , and ScPDSI for multicategory and multi-scalar drought identification are reported in terms of Pearson correlation coefficient. Through a series of cross-comparisons, our result explains that the SZI , SPEI , and ScPDSI drought indices presented dissimilar abilities in different regions, which of course, raises the issue of regional applicability. The performance of SZI is better than SPEI and ScPDSI in both humid and non-humid regions. Although the consistency of SPEI is similar to SZI across different temporal scale, it is more appropriate for multi-scalar drought analysis in humid regions. The ScPDSI are inconsistent in identifying multicategory drought. The enhanced drought appraisal with the SZI is the consequence of a more objective evaluation of atmospheric water demand by incorporating precipitation, runoff, and change in water storage, all that control meteorological, hydrological, and agricultural droughts, respectively. The SZI can offer a better multi-category and multi-scalar droughts information, which could aid in providing valuable early warning of rapidly evolving drought most notably in the water-limited region. [ABSTRACT FROM AUTHOR]

The integration of terrestrial- and satellite-based quantum key distribution (QKD) experiments has markedly advanced global-scale quantum networks, showcasing the growing maturity of quantum technologies. Notably, the use of unmanned aerial vehicles (UAVs) as relay nodes has emerged as a promising method to overcome the inherent limitations of fiber-based and low-Earth orbit (LEO) satellite connections. This paper introduces a protocol for measurement-device-independent QKD (MDI-QKD) using photon orbital angular momentum (OAM) encoding, with UAVs as relay platforms. Leveraging UAV mobility, the protocol establishes a secure and efficient link, mitigating threats from untrusted UAVs. Photon OAM encoding addresses reference frame alignment issues exacerbated by UAV jitter. A comprehensive analysis of atmospheric turbulence, state-dependent diffraction (SDD), weather visibility, and pointing errors on free-space OAM-state transmission systems was conducted. This analysis elucidates the relationship between the key generation rate and propagation distance for the proposed protocol. Results indicate that considering SDD significantly decreases the key rate, halving previous data results. Furthermore, the study identifies a maximum channel loss capacity of 26 dB for the UAV relay platform. This result is pivotal in setting realistic parameters for the deployment of UAV-based quantum communications and lays the foundation for practical implementation strategies in the field. [ABSTRACT FROM AUTHOR]

• The rainfall-runoff relationship has changed under climate change and human activities in the TRH region. • The impacts climate indicators of rainfall-runoff ratio in the sub-basins of TRH region were different. • The contribution rates of human activity in the YRB were a little higher than that in the YARB. Identifying the impact of climate change and human activities on rainfall-runoff relationship in the Three-River Headwaters (TRH) region is essential for water source conservation, ecological security, and biodiversity maintenance of China and East Asia. In this paper, the runoff-rainfall ratio was used as the index of rainfall-runoff relationship. Different methods were employed to identify the impact indicators and quantitative assessment of rainfall-runoff relationship from 1957 to 2016. The results are the following: (1) the rainfall-runoff relationship has changed in the source regions of Yangtze River basin (YARB) and Yellow River (YRB), and runoff-rainfall ratio has increased by 2.9% and decreased by 3.2%, respectively; (2) the main climate indicators of runoff-rainfall ratio were rainfall, potential evaporation and sunshine hours in the YARB, and rainfall, potential evaporation and temperature in the YRB; (3) the contribution rates of human activity in the YRB were a little higher than that in the YARB, and the contribution rates of climate change and human activity were 90.9% and 9.1% in the YARB and 42.9% and 57.1% in the YRB. The results can provide invaluable information for managing water resources and taking ecological protection measures. [ABSTRACT FROM AUTHOR]

We propose an efficient scheme for joint remote state preparation (JRSP) of arbitrary multi-qubit states from two senders to one receiver with the 100% successful probability. Quantum channel is composed of maximally three-qubit entangled states, and several special mutually orthogonal measurement basis are constructed without the introduction of auxiliary particles. We also calculate the total classical communication cost required in the JRSP processes. The concrete JRSP procedures for remotely preparing single-qubit and two-qubit states are illustrated to prove explicitly the feasibility of this JRSP protocol. [ABSTRACT FROM AUTHOR]

As the longest tributary of the Yangtze River, the Hanjiang River has been a "lifeline" for the "Yangtze River Economic Belt of China". The water quality of the middle and lower reaches of the Hanjiang River (MLHR) has received considerable attention due to environmental degradation, increasing population, and water diversion project operations during the past decade. In this study, 16 water quality parameters from 14 national water quality monitoring stations along the MLHR were collected monthly from January 2021 to December 2022. Water quality index (WQI) methods coupling multivariate statistical techniques, e.g., seasonal Mann-Kendall test (SKT) and Mantel's test, were applied to analyze and evaluate the spatiotemporal variations of water quality under different environmental and hydrological conditions. The Hazard Quotients (HQs) were used to assess the non-carcinogenic and carcinogenic risk for adults and children via ingestion and dermal pathways. The results showed that the overall water quality in the MLHR was classified as "excellent", with the average WQI higher than "91", and each single water quality indicator met Class I or Class II surface water quality standards of China. Ammonia (NH3-N), Total phosphorus (TP), Permanganate (CODMn), pH, and Arsenic (As) were significantly correlated with water level variations. CODMn and TP were decisive in explaining the WQI variations of the MLHR. NH3-N, water temperature, pH, and dissolved oxygen were key parameters for explaining WQI variations in most regions of the MLHR. As, Cadmium (Cd), and Chromium (Cr) presented potential health risks in the MLHR and should warrant close monitoring due to their significant health implications. Due to the continuous construction and operation of cascade hydro-projects, the synchronous monitoring of water quality and hydrological data of the MLHR should be conducted in the future. This study provides a scientific reference for managing water quality in the MLHR and similar natural riverine water bodies. [ABSTRACT FROM AUTHOR]

Based on the logic Bell states, we present two novel multi-party quantum key agreement (QKA) protocols under collective noise. The proposed protocols make full use of four-qubit logic Bell states as quantum resources and perform the novel encoding operation to generate the shared key. The security analysis shows that these two protocols can resist against both participant and outsider attacks. Furthermore, compared with the other existing multi-party QKA protocols over collective noise, our protocols have higher qubit efficiency. Finally, we perform the simulation of the relationship between efficiency and security, which is completely consistent with the conclusion of the security analysis of the protocols. [ABSTRACT FROM AUTHOR]

In this paper, we present an efficient scheme for remote state preparation of arbitrary n-qubit states with real coefficients. Quantum channel is composed of n maximally two-qubit entangled states, and several appropriate mutually orthogonal bases including the real parameters of prepared states are delicately constructed without the introduction of auxiliary particles. It is noted that the successful probability is 100% by using our proposal under the condition that the parameters of prepared states are all real. Compared to general states, the probability of our protocol is improved at the cost of the information reduction in the transmitted state. [ABSTRACT FROM AUTHOR]

The reference-frame-independent quantum key distribution (RFI-QKD) allows the authorized users to share secrete keys without active alignment of the reference frames, which is beneficial for the implementation over free-space channel. However, the performance of free-space RFI-QKD could notably degrade due to the influence of atmospheric conditions. In this paper, we investigate the transmission attenuation of free-space channel in uplink and downlink scenario, respectively. Furthermore, we also simulate the relationships between the diffraction-caused attenuation and the apertures of sending and receiving optics. Then, the key generation rate of RFI-QKD and BB84 protocol are compared in different links with reference frame deviations. Simulation results show that the transmission attenuation due to diffraction can be reduced by choosing appropriate optical apertures, and better performance of free-space RFI-QKD can be achieved in downlink configuration. [ABSTRACT FROM AUTHOR]

In this paper, we propose a two-party and a three-party controlled quantum key agreement (QKA) protocols with three-qubit GHZ states and Bell measurements. Compared with previous protocols, the significant change of our schemes is that a supervisor is introduced for controlling the agreement process to improve the controllability. Moreover, our protocols ensure each communication participant contribute equally to the agreement keys, and all participants can negotiate the shared keys without exchanging classical bits between them. The performance analysis shows that our protocols can be immune to outsider and participant attack. [ABSTRACT FROM AUTHOR]