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The construction of new towns is one of the main measures to evacuate urban populations and promote regional coordination and urban–rural integration in China. Mining the spatio-temporal pattern of new town hot spots based on multivariate data and analyzing the influencing factors of new town construction hot spots can provide a strategic basis for new town construction, but few researchers have extracted and analyzed the influencing factors of new town internal hot spots and their classification. In order to define the key points of Wuhan's new town construction and promote the construction of new cities in an orderly and efficient manner, this paper first constructs a space-time cube based on the luminous remote sensing data from 2010 to 2019, extracts hot spots and emerging hot spots in Wuhan New City, selects 14 influencing factor indicators such as population density, and uses bivariate Moran's index to analyze the influencing factors of hot spots, indicating that the number of bus stops and vegetation coverage rate are the most significant. Secondly, the disorderly multivariate logistic regression model is used to analyze the influencing factors of emerging hot spots. The results show that population density, vegetation coverage, road density, distance to water bodies, and distance to train stations are the most significant factors. Finally, based on the analysis results, some relevant suggestions for the construction of Wuhan New City are proposed, providing theoretical support for the planning and policy guidance of new cities, and offering reference for the construction of new towns in other cities, promoting the construction of high-quality cities. [ABSTRACT FROM AUTHOR]

In this work, the input–output finite-time stability (IO-FTS) of a class of continuous-time switched systems characterized by uncertainties and subjected to external disturbances is studied under asynchronous switching by means of the sliding mode control (SMC) method. The IO-FTS poses a finite-time constraint problem, which involves addressing two main issues: firstly, ensuring that the state trajectory of the switched system reaches the given sliding mode surface within the specified time, and secondly, achieving IO-FTS for the closed-loop switched system during asynchronous switching. To address these issues, we apply a partitioning strategy and construct asynchronous sliding mode controllers with adjustable parameters to ensure the reachability of the system's state trajectory within a finite time. Subsequently, we employ a multiple Lyapunov function (MLF) approach to provide sufficient conditions that ensure IO-FTS during the whole phase [ 0 , T ] for the resulting switched system. Additionally, we analyze the asynchronous characteristics concerning the reachability phase of the designed sliding surface, considering the system's switching properties. Finally, we demonstrate the efficacy of the proposed approach with a numerical example. [ABSTRACT FROM AUTHOR]

In this work, the sliding mode control (SMC) problem is investigated for a class of Lur'e nonlinear switched systems subject to finite channels constraints, which may lead to data collision. To solve this phenomenon, the Weighted Try-Once-Discard (WTOD) protocol is proposed on the sensor-to-controller (S/C) channels to regulate which one sensor node is permitted to send data via the communication network at each instant. A key issue of this work is how to integrate the WTOD protocol into the design of observer and the sliding mode controller for the switched systems. To this end, a token-dependent observer is constructed to estimate the unmeasured states, and then an observer-based SMC law is properly designed. Moreover, by constructing a Lur'e-type Lyapunov function interconnected with a cone-bounded nonlinearity, some sufficient conditions are established such that the reachability with a sliding domain around the specified sliding surface is achieved, meanwhile, the exponential stability of the resultant closed-loop switched systems is guaranteed. Finally, some numerical simulation results are provided. [ABSTRACT FROM AUTHOR]

Governmental attention towards the high-quality development of the Yellow River basin has brought new development opportunities for the hotel industry. This study aims to reveal the spatial-temporal evolution patterns and influencing factors of hotels in the Yellow River Basin from 2012 to 2022, based on economic, social, and physical geographic data of 190,000 hotels in the Yellow River flowing. With the help of a GIS technology system, the spatial-temporal evolution patterns of all hotels, star hotels, and ordinary hotels were explored, respectively. Then, the significant influencing factors of these patterns were revealed by using geographic detector and Person correlation analysis. The following conclusions were drawn: (1) the overall scale of the hotel industry in the Yellow River Basin expanded year by year, achieving rapid growth from 2016, and fluctuating around 2020 due to the impact of the novel coronavirus epidemic; the overall spatial distribution had significant regional differences, showing the structural characteristics of "southeast more, northwest less"; (2) there was a great difference in the degree of spatial autocorrelation agglomeration among prefecture-level cities, and the degree of agglomeration of both the hotel industry as a whole and general hotels decreased year by year, showing a random distribution in 2022; star hotels were always distributed randomly. Additionally, a strong synergistic correlation was shown between the number of ordinary hotels and the number of star hotels in local space; (3) overall, the development of the hotel industry was significantly affected by seven factors: structural force, macro force, ecological force, internal power, consumption power, intermediary power, and external power. There were differences in the forces acting on different types of hotels, which gives a pattern recognition in-depth. [ABSTRACT FROM AUTHOR]

Summary: This article focuses on the sliding mode control of a class of interval type‐2 fuzzy systems with immeasurable states. During the data transmission from the sensor to the controller, the intermittent denial‐of‐service (DoS) attacks may be launched by vicious opponents. A key issue is to evaluate the tolerable region of the attacks for keeping the desired dynamic performance of the controlled interval type‐2 fuzzy systems. To this end, two weighting coefficients are first introduced to construct new membership functions. Based on this, a switched interval type‐2 fuzzy estimator is proposed to estimate the immeasurable state and compensate for the lost measurements caused by DoS attacks. And then, considering different DoS statues, a switched sliding mode controller transiting between the attack free and active cases is synthesized such that the specified sliding surface can be reached. In addition, the acceptable DoS region is quantitatively analyzed via a switched Lyapunov function. It is proven that the input‐to‐state stability of the sliding mode dynamics and the error system can be ensured within this tolerable DoS region. Finally, a simulation example is provided to illustrate the proposed control scheme. [ABSTRACT FROM AUTHOR]

This study copes with the guaranteed cost problem for a class of Markovian jump Lur'e systems via sliding mode control technique, in which the scheduling of controller signals towards the actuators is regulated by the Round‐Robin protocol. This means that at each transmission instant, only one actuator node can access the transmission network and the other actuators cannot obtain any new control information. In order to deal with this phenomenon, an updating rule as compensator is proposed, based on which the other actuators utilise the past control signals stored in the corresponding buffers. Then, a mode‐token‐dependent sliding mode controller is designed, in which the characteristic of the Lur'e non‐linearities is involved. Furthermore, by introducing a new token‐dependent Lur'e‐type Lyapunov function, the stochastic stability of the resultant closed‐loop systems is analysed, and the guaranteed cost performance is attained. Finally, a dynamic Leontief input–output model is adopted to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

Summary: This work considers the sliding mode control problem of a class of discrete‐time uncertain switched systems subject to detecting‐delay on mode signals, which may result in the asynchronous phenomenon between the controller and the switched system. Since the mode information of the controlled system is not available for the controller in time, a mode‐independent sliding surface will be introduced, by which an asynchronous sliding mode controller is designed, whose control gain and robust parameter will be changing according to the controller mode. In the analysis on the stability of the closed‐loop control system and the reachability of the specified sliding surface, the asynchronous characteristics are detailedly investigated. It is shown that the Lyapunov function may be not always decreasing along the state trajectories during the unmatched interval of controller modes and system modes. Nevertheless, it is proven that the state trajectories can be driven into a sliding region around the specified sliding surface in finite time. Finally, some numerical simulation results are provided. [ABSTRACT FROM AUTHOR]

The problem of sliding mode control (SMC) is investigated for a class of uncertain switched systems subject to unmeasurable state and assigned finite (possible short) time constraint. A key issue is how to ensure the finite-time boundedness (FTB) of system state during reaching phase and sliding motion phase. To this end, a state observer is constructed to estimate the unmeasured states. And then, a state estimate-based SMC law is designed such that the state trajectories can be driven onto the specified integral sliding surface during the assigned finite time interval. By means of partitioning strategy, the corresponding FTB over reaching phase and sliding motion phase are guaranteed and the sufficient conditions are derived via average dwell time technique. Finally, an illustrative example is given to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

Objective: Hypomyelinating disorders are a group of clinically and genetically heterogeneous diseases characterized by neurological deterioration with hypomyelination visible on brain MRI scans. This study was aimed to clarify the clinical and genetic features of HMDs in Chinese population. Methods: 119 patients with hypomyelinating disorders in Chinese population were enrolled and evaluated based on their history, clinical manifestation, laboratory examinations, series of brain MRI with follow-up, genetic etiological tests including chromosomal analysis, multiplex ligation probe amplification, Sanger sequencing, targeted enrichment-based next-generation sequencing and whole exome sequencing. Results: Clinical and genetic features of hypomyelinating disorders were revealed. Nine different hypomyelinating disorders were identified in 119 patients: Pelizaeus-Merzbacher disease (94, 79%), Pelizaeus-Merzbacher-like disease (10, 8%), hypomyelination with atrophy of the basal ganglia and cerebellum (3, 3%), GM1 gangliosidosis (5, 4%), GM2 gangliosidosis (3, 3%), trichothiodystrophy (1, 1%), Pol III-related leukodystrophy (1, 1%), hypomyelinating leukodystrophy type 9 (1, 1%), and chromosome 18q deletion syndrome (1, 1%). Of the sample, 94% (112/119) of the patients were genetically diagnosed, including 111 with mutations distributing across 9 genes including PLP1, GJC2, TUBB4A, GLB1, HEXA, HEXB, ERCC2, POLR3A, and RARS and 1 with mosaic chromosomal change of 46, XX,del(18)(q21.3)/46,XX,r(18)(p11.32q21.3)/45,XX,-18. Eighteen novel mutations were discovered. Mutations in POLR3A and RARS were first identified in Chinese patients with Pol III-related leukodystrophy and hypomyelinating leukodystrophy, respectively. Significance: This is the first report on clinical and genetic features of hypomyelinating disorders with a large sample of patients in Chinese population, identifying 18 novel mutations especially mutations in POLR3A and RARS in Chinese patients, expanding clinical and genetic spectrums of hypomyelinating disorders. [ABSTRACT FROM AUTHOR]

Central core disease is a rare inherited neuromuscular disorder caused by mutations in ryanodine receptortype 1 gene. The clinical phenotype of the disease is highly variable. We report a Chinese pedigree with central core disease confirmed by the gene sequencing. All 3 patients in the family presented with mild proximal limb weakness. The serum level of creatine kinase was normal, and electromyography suggested myogenic changes. The histologic analysis of muscle biopsy showed identical central core lesions in almost all of the muscle fibers in the index case. Exon 90-106 in the C-terminal domain of the ryanodine receptor type 1 gene was amplified using polymerase chain reaction. One heterozygous missense mutation G14678A (Arg4893Gln) in exon 102 was identified in all 3 patients. This is the first report of a familial case of central core disease confirmed by molecular study in mainland China. [ABSTRACT FROM AUTHOR]

In this paper, we used the same four-parameter function as Hathaway, Wilson, and Reichmann (1994) proposed and studied the temporal behavior of sunspot cycles 12–22. We used the monthly averages of sunspot areas and their 13-point smoothed data. Our results show the following. (1) The four-parameter function may reduce to a function of only two parameters. (2) As a cycle progresses, the two-parameter function can be accurately determined after 4–4.5 years from the start of the cycle. A good prediction can be made for the timing and size of the sunspot maximum and for the behavior of the remaining 5–10 years of the cycle. (3) The solar activity in the remaining and forthcoming years of cycle 23 is predicted. (4) The smoothed monthly sunspot areas are more suitable to be employed for prediction at the maximum and the descending period of a cycle, whereas at the early period of a cycle the (un-smoothed) monthly data are more suitable. [ABSTRACT FROM AUTHOR]

There is controversy about whether the amniotic fluid contains bacteria. With the use of sequencing-based methods, recent studies report that the amniotic fluid is colonized by microorganisms. However, background-contaminating DNA might lead to false-positive findings when such a low microbial biomass sample is examined. The purpose of this study was to determine whether the midtrimester amniotic fluid of patients who subsequently had normal pregnancy outcomes contains a microbial signature. In this prospective cohort study, 42 amniotic fluid samples were collected from 37 pregnancies (5 twin and 32 singletons) during genetic amniocentesis in the midtrimester. The subsequent pregnancy outcomes of all the participants were followed. Multiple methods were used to detect the presence of microorganisms in this study, which included cultivation, quantitative real-time polymerase chain reaction, and 16S ribosomal RNA gene sequencing. Multiple positive control samples (n=16) served as quality control samples and included 3 adult fecal samples, 4 vaginal swabs, and 9 artificial bacterial communities that were run in parallel with negative control samples (n=12) that included 4 samples from the hospital operating room and 8 samples from the laboratory, to account for background-contaminating DNA during each step of the experiments. No bacteria under anaerobic or aerobic conditions or genital mycoplasmas were cultured from any of the amniotic fluid samples. Quantitative polymerase chain reaction did not reveal greater copy numbers of 16S ribosomal RNA gene in amniotic fluid samples than in negative control samples. 16S Ribosomal RNA gene sequencing did not indicate a significant difference in the microbial richness or community structures between amniotic fluid and negative control samples. With multiple methods of microbiologic inquiry, no microorganisms were identified in the midtrimester amniotic fluid of healthy pregnancies with a normal pregnancy outcome. [ABSTRACT FROM AUTHOR]

Abstract: Pinewood nematode (PWN) is the causal agent of the pine wilt disease. Previous studies have suggested that secretions from the esophageal glands of PWN play an important role in pathogenicity. A cluster of three venom allergen-like protein genes and one pseudogene, Bx-vap-1, Bx-vap-2, Bx-vap-3 and Bx-vap-P, were identified within a 3.7-kb region. Additionally, three putative modification, transport and regulatory protein genes were also detected in the same flanking region of the Bx-vap gene cluster. Genes vap-1, -2 and -3 are functional and encode three major allelic variants of PWN venom allergen-like proteins. But Bx-vap-P is an untranscribed pseudogene. Genes vap-1, -2 and -3 produce predicted products of 204, 206 and 203 amino acid residues, respectively, including the putative signal peptide sequence at the amino termini. In situ mRNA hybridization analysis showed that the transcripts of genes vap-1, -2 and -3 accumulated exclusively within the esophageal gland cells of Bursaphelenchus xylophilus. [ABSTRACT FROM AUTHOR]

A time series of Hα filtergrams and two-dimensional Hα spectral data of the well-known post-flare loop system of April 27, 1981 are obtained at the Yunnan Observatory. The two-dimensional spectral data are analyzed quantitatively by means of the `multi-cloud model'' method. The line-of-sight velocity fields of the post-flare loop system are derived for three different times. The post-flare loop system is composed of a loop and an ejection. The loop almost faces the observer and the ejection is along the line-of-sight. A `double-loop'' model is proposed in order to explain the structure and evolution of the post-flare loop system. The distributions of the line-of-sight velocity and the evolution time of the post-flare loop system derived from a free-fall model are similar to those obtained from the observations. [Copyright &y& Elsevier]

We analysed precipitation and river water samples from the Lijiang River basin with the aim of understanding the important role of acid rain components, especially NH 4 , in chemical weathering of karst areas. First, analysis of the hydrochemical characteristics revealed the following: In the precipitation samples, the volume-weighted mean pH was 4.91, and the acid rain rate was 65%. The major ion composition was characterized by a dominance of NH 4 , Ca, SO 4 and NO 3 , accounting for 40.0%, 35.3%, 46.3% and 30.5%, respectively, of the total cation and anion concentrations. In the river water samples, the pH ranged from 6.75 to 9.16, with an average of 7.55. The major hydrogeochemical species in the river water samples were Ca–HCO 3 and Mg–HCO 3. Second, by employing chloride-normalized ratios of the other major ions in precipitation, we estimated that the contributions of SO 4 and NO 3 from the atmosphere to the river were53.6% and 35.0%, respectively. Third, combining the hydrochemical index with the value of δ13C DIC and using the hydrochemical composition method showed that the proportion of carbonate weathered (R) by NH 4 , H 2 SO 4 and HNO 3 from acid rain accounted for 9.3%, 9.4% and 3.1% of the total weathering rate, respectively, and the proportions in the upper reaches were significantly higher than those in the lower reaches of the river. The average values of the carbonate weathering proportion (R) and the carbonate weathering rate (CWR) due to acid rain were approximately 22.0% and 2.1 t/km2/yr, respectively. Taken together, our results revealed that carbonate weathering by acid rain can significantly increase the carbonate weathering rate, which is essential information for accurate estimation of the carbon cycle (namely, inorganic carbon sources and sinks). Image 1 • Analysis of hydrochemical characteristics of precipitation and river water. • NH 4 (H), H 2 SO 4 and HNO 3 may provide the required protons for weathering reactions. • Carbonate weathering by acid rain can significantly increase weathering rate. [ABSTRACT FROM AUTHOR]

Ganoderma triterpenes (GTs) are the major secondary metabolites of Ganoderma lucidum, a traditional Chinese medicine, popularly used for complementary cancer therapy. GTs are lanostane-tetracyclic triterpenes. They have been reported to possess anti-tumor, anti-inflammation, antioxidant, antimicrobial and blood fat reducing effects. To date, 316 GTs have been found and their similar chemical structures have proved difficult to elucidate. This paper compiles 316 naturally occurring triterpenes from Ganoderma based on the literature published through January 2013 along with their structures, physiological activities and 13C-NMR spectral data.