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Groundwater extraction from aquifers is a common practice for human use, and variations in groundwater levels can provide valuable information on the hydrogeological properties of the aquifer. However, reliable data on pumping rates and distribution are often lacking due to unsupervised groundwater pumping activities. This study presents a new mathematical model for transfer function modeling that depicts the drawdown response caused by pumping in an unconfined aquifer system. To account for the dense and unsupervised pumping events, the uniform pumping approach was used to estimate these effects. To more accurately represent unconfined flow, the model first integrates lagging theory into a response function derived from the Boussinesq equation. The lagging theory accounts for the effects of both inertial force and capillary suction. Furthermore, the model has been used to derive both specific yield and transmissivity along with two lagging parameters simultaneously using only groundwater level information from the Choshui River region in Taiwan. The estimated results suggest that this approach provides reliable estimates of hydrogeological parameters, demonstrating its usefulness for water resource management and water budget evaluation. Plain Language Summary: This study examines the process of extracting water from underground sources, known as aquifers, and how monitoring changes in water levels can provide valuable insights into the characteristics of the aquifer. It can be challenging to obtain accurate information on the amount of water being pumped out due to inadequate monitoring. The researchers have developed a novel approach to comprehending the impact of water extraction on the water levels in these subterranean regions. This method considers the general pattern of water use to pump out water without close monitoring. It also incorporates realistic ideas about how water moves through the ground, taking into account factors such as the delay in water movement and the role of different forces in the soil. The study applied this method to data from Taiwan's Choshui River area and was able to determine important details about the aquifer using only water level information. These findings hold promise for effective water resource management and the wise use of water. [ABSTRACT FROM AUTHOR]

Baseline determination is a prerequisite for desertification monitoring and assessment and also for the sustainable development of drylands. In this study based on long‐term remote sensing net primary production (NPP) data and combined with a local NPP scaling method, the desertification status in Central Asia is quantified, and NPP‐based objective baseline of desertification (potential NPP, NPPp), which could be more convenient and enables the desertification status measurable from local to global scales, is established by integrating space‐for‐time substitution, isolation forest (iForest) algorithm, and Monte Carlo simulations. More reliable than a fixed percentile‐based reference with subjective preference, the analyzed results show that across Central Asia over the past four decades, the NPPp ranged from 46.4 to 639.5 gC m−2 yr−1 with different land cover types and regions, and the general desertification status in the region was rated as a moderate degree with an average of 50.5%. From the 1980s to the 2000s in most regions of Central Asia, reversals of desertification occurred, but it intensified in the 2010s. This study may contribute to improving the existing framework of SDG Indicator 15.3.1. [ABSTRACT FROM AUTHOR]

There is a limited understanding of agricultural land dynamics across global drylands and the impacts of transitions between agricultural land and land cover on net primary productivity (NPP) changes. This study attempted to fill this gap by examining agricultural land changes and NPP responses in drylands. A data‐driven assessment of effects on the NPP of individual agricultural land displacement was carried out using three methods: the mean difference method, a newly introduced ridge‐regression method, and a proposed method based on actual change excluding climate impact. Increases in NPP were accompanied by agricultural land transitions from natural land cover and expected forests. The agricultural expansion mainly replaced sparse vegetation and grassland and increased the overall NPP of the dryland ecosystem. The mean difference method and ridge‐regression method overestimated the NPP increase caused by agricultural land expansion. Land use change contributed more than 70% to NPP increase in the new agricultural area. However, land use change has less effect on total NPP in drylands than climate change. Monitoring agricultural land dynamics and distinguishing NPP changes caused by different agricultural land transitions is helpful for targeted management and sustainable development of agriculture in drylands. [ABSTRACT FROM AUTHOR]

In recent years, hazardous e‐mails arose, such as the e‐mails infected with 'viruses' or 'worms' spreading destructive programs and the 'Phishing Mails' defrauding e‐mail accounts of the users. The number of spams continue to grow. With the related problems of spam coming to be more severe, the spam topics have become significant in various research domains. The common filtering methods include black/white list, rule learning, and those based on text classification, such as Naïve Bayes, support vector machine, and boosting trees, multi‐agent and genetic algorithm. Among these, the methods based on text classification are most widely applied. Moreover, some efficient methods were proposed to consider only the e‐mail's header section, based on which both operating efficiency and classification efficiency could be improved. By applying machine learning technique and decision tree data mining algorithm C4.5, this study aims to propose an efficient spam filtering method with the following features: (i) proposing a two‐phase filtering mechanism to scan mainly e‐mail's header and auxiliary content. (ii) Reducing the problem of false positive. The experimental results show that the authors' method has a considerably high accuracy rate of 98.76%. Compared with some other methods of using the same spam data sets or of deep learning‐based, their method obviously has an excellent performance. [ABSTRACT FROM AUTHOR]

A tandem phospha‐Michael addition/N‐acylation/intramolecular Wittig reaction of in situ formed aza‐o‐QMs is disclosed. This approach features high functional group tolerance and provides a convenient and practical access to biologically significant indole derivatives (37 examples, up to 91% yield) under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Summary: A mega‐frame with a vibration control substructure (MFVCS) is a tuned mass damper system that converts substructures into a tuned mass. In this study, a kind of MFVCS using lead–rubber bearings (LRBs) to connect the vibration control substructure to the mega‐frame was proposed. To investigate the damping effect of this MFVCS, a series of shaking table tests were conducted, and the seismic responses of the MFVCS were compared with those of the traditional mega‐frame structure (TMFS). The results show that the seismic responses of the MFVCS are clearly smaller than those of the TMFS; additionally, the proposed MFVCS can provide a sufficient damping effect under different ground motions. Finite element (FE) models of the TMFS and MFVCS were established and validated by experimental results. Finally, the simulation results adopting different LRB models (equivalent linear and nonlinear elements) were compared, and the results indicate that simulation results can be obtained with greater accuracy from the FE model with a nonlinear LRB model than that with a linear LRB model. [ABSTRACT FROM AUTHOR]

Combatting land degradation and achieving land degradation neutrality are crucial to securing a globally sustainable future. Wuepper et al. (Global Change Biology, 2021) propose an integrated approach to delineate global land degradation based on the concept of natural resources 'debt' that combines a diverse range of soil and vegetation indicators. The research is novel both in considering a variety of indicators and in distinguishing between the current state and historical/natural status with (or without) human impact. This novel framework will implement more effective regulatory interventions and land‐use policies, and assist in achieving the long‐term sustainability of terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Objective: Early screening of non‐alcoholic fatty liver disease (NAFLD) is of great significance for the early detection and intervention in NAFLD. MicroRNAs (miRNAs) are important regulators of metabolic diseases including NAFLD. The aim of this study was to investigate the association of serum miR‐29a‐c with NAFLD in a Chinese population. Methods: Participants were divided into four groups based on the presence or absence of NAFLD and/or type 2 diabetes mellitus (T2DM). Quantitative polymerase chain reaction analysis was performed to quantify serum level of miR‐29a‐c. The association of miR‐29a‐c with NAFLD was evaluated. Results: Serum miR‐29b, but not miR‐29a or miR‐29c, was positively associated with NAFLD (odds ratio [OR] 2.04 [1.16‐ 3.58], P = 0.013). Additionally, age, serum triglyceride and fasting plasma glucose (FPG) levels were independently associated with miR‐29b (β ± standard error [SE] = 0.004 ± 0.002, P = 0.019 for age; β ± SE = 0.110 ± 0.054, P = 0.042 for triglyceride; and β ± SE = 0.389 ± 0.161, P = 0.016 for FPG). MiR‐29b level was positively correlated with intrahepatic lipid content (β ± SE = 6.055 ± 2.630, P = 0.024) after adjusted for age, sex, and body mass index. Conclusions: Serum miR‐29b was associated with intrahepatic lipid content and NAFLD in a Chinese population‐based study. [ABSTRACT FROM AUTHOR]

Background: A challenge for R2 and R2* methods in measuring liver iron concentration (LIC) is that fibrosis, fat, and other hepatic cellular pathology contribute to R2 and R2* and interfere with LIC estimation.Purpose: To examine the interfering effects of fibrosis, fat, and other lesions on R2* LIC estimation and to use quantitative susceptibility mapping (QSM) to reduce these distortions.Study Type: Prospective.Phantoms, Subjects: Water phantoms with various concentrations of gadolinium (Gd), collagen (Cl, modeling fibrosis), and fat; nine healthy controls with no known hepatic disease, nine patients with known or suspected hepatic iron overload, and nine patients with focal liver lesions.Field Strength/sequence: The phantoms and human subjects were imaged using a 3D multiecho gradient-echo on clinical 1.5T and 3T MRI systems.Assessment: QSM and R2* images were postprocessed from the same gradient-echo data. Fat contributions to susceptibility and R2* were corrected in signal models for LIC estimation.Statistical Tests: Polynomial regression analyses were performed to examine relations among susceptibility, R2* and true [Gd] and [Cl] in phantoms, and among susceptibility and R2* in patient livers.Results: In phantoms, R2* had a strong nonlinear dependency on [Cl], [fat], and [Gd], while susceptibility was linearly dependent (R2  > 0.98). In patients, R2* was highly sensitive to liver pathological changes, including fat, fibrosis, and tumors, while QSM was relatively insensitive to these abnormalities (P = 0.015). With moderate iron overload, liver susceptibility and R2* were not linearly correlated over a common R2* range [0, 100] sec-1 (P = 0.35).Data Conclusion: R2* estimation of LIC is prone to substantial nonlinear interference from fat, fibrosis, and other lesions. QSM processing of the same gradient echo MRI data can effectively minimize the effects of cellular pathology.Level Of Evidence: 1 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;48:1069-1079. [ABSTRACT FROM AUTHOR]

Under earthquake action, the reinforced concrete structure at the edge of the CAP1400 nuclear power plant foundation slab will be uplifted. In order to determine the seismic performance of this structure, a 1 : 12 scale shaking table test model was fabricated using gypsum as simulated concrete in order to meet scaled design requirements. By testing this model, the seismic response of the structure with consideration of the foundation uplift was obtained. Numerical analyses of the test model and the prototype structure were conducted to gain a better understanding of the structural seismic performance. When subjected to earthquakes, the foundation slab of the nuclear power plant experiences a slight degree of uplift but remains in the elastic stage due to the weight of the structure above, which provides an antioverturning moment. The numerical simulation is in general agreement with the test results, suggesting numerical simulations could be accurately employed in place of physical tests. The superstructure displacement response was found not to affect the safety of adjacent structures, and the seismic performance of the structure was shown to meet the relevant design requirements, demonstrating that this approach to modelling can serve as a design basis for the CAP1400 nuclear power demonstration project. [ABSTRACT FROM AUTHOR]

With the third-generation normalized difference vegetation index and a multiple-timescale drought index [standardized precipitation and evapotranspiration index (SPEI)], the relationships between vegetation activity in the growing season and drought occurrences during various seasons and at different timescales were investigated in northern China. Although poorly understood previously, knowledge of these relationships is crucial for climate, vegetation and hydrological studies. Our results show that over the past three decades, vegetation activity during the growing season was significantly correlated ( p < 0⋅05) with drought occurrences over 78⋅5% of northern China and highly significantly correlated ( p < 0⋅001) in semi-arid regions. In addition, there were spatially variable responses of vegetation activity to the seasonality of drought events across northern China. When drought events occurred in pre-season in the northern part of Inner Mongolia and Heilongjiang, parts of Shaanxi and Shanxi, and the western part of Xinjiang, they appear to have impacted vegetation activity, as indicated by the short and medium timescales of the drought indices (SPEI-3 and SPEI-6, with 3 and 6 months of accumulation, respectively). In the eastern part of Inner Mongolia, eastern part of Gansu and Qinghai, and southern parts of Ningxia, droughts during the growing season played a key role in vegetation growth, as recorded by the drought indices at all four timescales (SPEI-3, SPEI-6, SPEI-12 and SPEI-24). In addition, we also observed spatial variations in the responses of vegetation activity to droughts in northern China. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In our previous study, we have prepared a novel antibacterial ultra-high molecular weight polyethylene/chlorhexidine acetate-montmorillonoid (UHMWPE/CA-MMT) composites and examined its crystallization process and kinetics [1]. In this work, the rheological behaviors of pure UHMWPE, UHMWPE/MMT, UHMWPE/CA, and UHMWPE/CA-MMT were characterized. The results showed that MMT can increase the viscosity of the polymer composites and CA can act as a plasticizer in the composites. Compared with UHMWPE/CA, UHMWPE/CA-MMT had lower η*, G′, and G″. The TGA result indicated that CA-MMT has higher thermostability than CA. Hence, CA-MMT has the lower thermal decomposition ratio at high temperature than CA when it is blended with polymer. The TGA result could be used to explain that UHMWPE/CA-MMT composites had better plasticizer effect than UHMWPE/CA composites. POLYM. COMPOS., 36:47-50, 2015. © 2014 The Authors Polymer Composites published by Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Changes in the wind-energy environment between AD 1359 and 2010 in the Taklimakan Desert (central Asia) are recorded by the evolution of Chinese tamarisk ( Tamarix taklamakanensis) nebkhas. The carbonate component and sedimentological properties of the nebkha excavated during the study, together with AMS 14 C dating control, indicate that significant regional environmental changes have occurred in the central Taklimakan Desert during the last 700 years. The nebkha data presented show that in the periods of AD c. 1480-1560, c. 1640-1690, c. 1760-1820, c. 1860-1930 and c. 1970-1980 the Taklimakan Desert was a relatively high wind-energy environment. Although changes in the wind-energy regime in the desert were mainly in phase with fluctuations of the Siberian High, the wind systems and the variations in wind energy exhibit slight differences when compared with the Tarim Basin. Nebkhas that develop in this region originate from the surfaces of mobile dunes or sand sheets, which differs from the origins of nebkhas found in other arid regions of China. [ABSTRACT FROM AUTHOR]

Changes in the crystal morphology, crystallinity, and the melting process of thermoplastics resulted in significant changes in the processability and mechanical behavior of composites. In our former study, we prepared a novel antibacterial UHMWPE/CA-MMT composite. In this study, the crystal process and crystallization kinetics of pure UHMWPE, UHMWPE/MMT, UHMWPE/CA, and UHMWPE/CA-MMT were characterized by differential scanning calorimeter (DSC). The results showed that the chlorhexidine acetate (CA) and montmorillonite (MMT) could cause strong heterogeneous nucleation. The results of crystallization kinetics indicated that the addition of CA could decrease the crystallization rate constant K value and widen the range of the crystal growth temperature. The reological behaviors of four samples were carried out by a physical MCR301 rheometer. The results showed that the CA could bring down the complex viscosity of composites, thus affecting the crystal process or crystallization kinetics. POLYM. COMPOS., 33:1987-1992, 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

A grading system was developed to classify shiitake automatically into various grades of quality in terms of size, shape and color. A shiitake is scanned with a color charge-coupled-device camera and then various geometrical and color characteristics are determined by image processing. The online grading procedure includes the following sequences in processing dried shiitake: (a) color abnormality is eliminated by image analysis; (b) broken caps are detected by calculation of the area-to-perimeter ratio; and (c) size is determined by pixel counting from the bottom view. Image processing and algorithmic manipulations are done on a personal computer (PC) while grading is carried out by a programmable logic controller (PLC). The PLC accepts grading instructions from the PC, hence controls the grading mechanisms. Pilot system validation was done on 250 dried shiitake samples and resulted in a 97.6% accuracy rate. This result is better than that by visual inspection. A complete grading cycle takes 4.8 s, of which the PC unit participates 0.3–0.7 s depending on the physical complexity of the shiitake being processed. [ABSTRACT FROM AUTHOR]

The critical breakthrough pressure related to the membrane surface wettability and pore size is a key parameter determining membrane performance in particular applications, such as oil–water mixture separations. A series of hydrophilic polysulfone hollow‐fiber membranes with different pore sizes were prepared and characterized to evaluate the separation performance of oil‐in‐water emulsions and to develop an optimum membrane for such emulsions. For the optimum membrane, the absolute value for the cosine of the surface oil droplet contact angle (0.72) was close to the ratio of the outer surface pore size to the oil droplet size (0.71); it was also similar to the absolute value of the cosine of the underwater oil contact angle on the polysulfone material (0.65). From the point of view of the surface wettability, theoretical calculations were performed to select a suitable membrane with the aim of reaching the maximum efficiency in practical oil–water mixture separation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47615. [ABSTRACT FROM AUTHOR]

The maleo­nitrile moiety of the title compound, (2 Z)-2,3-bis­[(4-nitro­benzyl)­sulfanyl]­but-2-ene­di­nitrile, C18H12N4O4S2, is almost planar. The two benzene rings are nearly parallel to each other and perpendicular to the maleo­nitrile plane. Intermolecular S⃛S and π-π interactions are observed in the crystal structure. [ABSTRACT FROM AUTHOR]