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1.
Entropy (Basel) ; 26(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38667893

RESUMO

The adjoint function of connection number has unique advantages in solving uncertainty problems of water resource complex systems, and has become an important frontier and research hotspot in the uncertainty research of water resource complex problems. However, in the rapid evolution of the adjoint function, some problems greatly limit the application of the adjoint function in the research of water resources. Therefore, based on bibliometric analysis, development, practical application issues, and prospects of the hot directions are analyzed. It is found that the development of the connection number of water resource set pair analysis can be divided into three stages: (1) relatively sluggish development before 2005, (2) a period of rapid advancement in adjoint function research spanning from 2005 to 2017, and (3) a subsequent surge post-2018. The introduction of the adjoint function of connection number promotes the continuous development of set pair analysis of water resources. Set pair potential and partial connection number are the crucial research directions of the adjoint function. Subtractive set pair potential has rapidly developed into a relatively independent and important trajectory. The research on connection entropy is comparatively less, which needs to be further strengthened, while that on adjacent connection number is even less. The adjoint function of set pair potential can be divided into three major categories: division set pair potential, exponential set pair potential, and subtraction set pair potential. The subtraction set pair potential, which retains the original dimension and quantity variation range of the connection number, is widely used in water resources and other fields. Coupled with the partial connection number, a series of new connection number adjoint functions have been developed. The partial connection number can be mainly divided into two categories: total partial connection number, and semi-partial connection number. Among these, the calculation expression and connotation of total partial connection numbers have not yet reached a consensus, accompanied by the slow development of high-order partial connection numbers. Semi-partial connection number can describe the mutual migration movement between different components of the connection number, which develops rapidly. With the limitations and current situation described above, promoting the exploration and application of the adjoint function of connection number in the field of water resources and other fields of complex systems has become the focus of future research.

2.
Nature ; 626(8001): 1141-1148, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326620

RESUMO

The calcium-sensing receptor (CaSR) is a family C G-protein-coupled receptor1 (GPCR) that has a central role in regulating systemic calcium homeostasis2,3. Here we use cryo-electron microscopy and functional assays to investigate the activation of human CaSR embedded in lipid nanodiscs and its coupling to functional Gi versus Gq proteins in the presence and absence of the calcimimetic drug cinacalcet. High-resolution structures show that both Gi and Gq drive additional conformational changes in the activated CaSR dimer to stabilize a more extensive asymmetric interface of the seven-transmembrane domain (7TM) that involves key protein-lipid interactions. Selective Gi and Gq coupling by the receptor is achieved through substantial rearrangements of intracellular loop 2 and the C terminus, which contribute differentially towards the binding of the two G-protein subtypes, resulting in distinct CaSR-G-protein interfaces. The structures also reveal that natural polyamines target multiple sites on CaSR to enhance receptor activation by zipping negatively charged regions between two protomers. Furthermore, we find that the amino acid L-tryptophan, a well-known ligand of CaSR extracellular domains, occupies the 7TM bundle of the G-protein-coupled protomer at the same location as cinacalcet and other allosteric modulators. Together, these results provide a framework for G-protein activation and selectivity by CaSR, as well as its allosteric modulation by endogenous and exogenous ligands.


Assuntos
Proteínas Heterotriméricas de Ligação ao GTP , Receptores de Detecção de Cálcio , Humanos , Regulação Alostérica/efeitos dos fármacos , Cinacalcete/farmacologia , Microscopia Crioeletrônica , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Proteínas Heterotriméricas de Ligação ao GTP/metabolismo , Ligantes , Lipídeos , Nanoestruturas/química , Poliaminas/metabolismo , Conformação Proteica/efeitos dos fármacos , Receptores de Detecção de Cálcio/química , Receptores de Detecção de Cálcio/metabolismo , Receptores de Detecção de Cálcio/ultraestrutura , Especificidade por Substrato , Triptofano/metabolismo , Cálcio/metabolismo
3.
bioRxiv ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38234749

RESUMO

Drugs acting as positive allosteric modulators (PAMs) to enhance the activation of the calcium sensing receptor (CaSR) and to suppress parathyroid hormone (PTH) secretion can treat hyperparathyroidism but suffer from side effects including hypocalcemia and arrhythmias. Seeking new CaSR modulators, we docked libraries of 2.7 million and 1.2 billion molecules against transforming pockets in the active-state receptor dimer structure. Consistent with simulations suggesting that docking improves with library size, billion-molecule docking found new PAMs with a hit rate that was 2.7-fold higher than the million-molecule library and with hits up to 37-fold more potent. Structure-based optimization of ligands from both campaigns led to nanomolar leads, one of which was advanced to animal testing. This PAM displays 100-fold the potency of the standard of care, cinacalcet, in ex vivo organ assays, and reduces serum PTH levels in mice by up to 80% without the hypocalcemia typical of CaSR drugs. Cryo-EM structures with the new PAMs show that they induce residue rearrangements in the binding pockets and promote CaSR dimer conformations that are closer to the G-protein coupled state compared to established drugs. These findings highlight the promise of large library docking for therapeutic leads, especially when combined with experimental structure determination and mechanism.

4.
Proc Natl Acad Sci U S A ; 121(1): e2310727120, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38150499

RESUMO

Intrinsically disordered regions (IDR) and short linear motifs (SLiMs) play pivotal roles in the intricate signaling networks governed by phosphatases and kinases. B56δ (encoded by PPP2R5D) is a regulatory subunit of protein phosphatase 2A (PP2A) with long IDRs that harbor a substrate-mimicking SLiM and multiple phosphorylation sites. De novo missense mutations in PPP2R5D cause intellectual disabilities (ID), macrocephaly, Parkinsonism, and a broad range of neurological symptoms. Our single-particle cryo-EM structures of the PP2A-B56δ holoenzyme reveal that the long, disordered arms at the B56δ termini fold against each other and the holoenzyme core. This architecture suppresses both the phosphatase active site and the substrate-binding protein groove, thereby stabilizing the enzyme in a closed latent form with dual autoinhibition. The resulting interface spans over 190 Šand harbors unfavorable contacts, activation phosphorylation sites, and nearly all residues with ID-associated mutations. Our studies suggest that this dynamic interface is coupled to an allosteric network responsive to phosphorylation and altered globally by mutations. Furthermore, we found that ID mutations increase the holoenzyme activity and perturb the phosphorylation rates, and the severe variants significantly increase the mitotic duration and error rates compared to the normal variant.


Assuntos
Proteína Fosfatase 2 , Proteína Fosfatase 2/metabolismo , Jordânia , Fosforilação , Mutação , Holoenzimas/genética , Holoenzimas/metabolismo
5.
J Chem Phys ; 158(21)2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37260014

RESUMO

Mutations in protein phosphatase 2A (PP2A) are connected to intellectual disability and cancer. It has been hypothesized that these mutations might disrupt the autoinhibition and phosphorylation-induced activation of PP2A. Since they are located far from both the active and substrate binding sites, it is unclear how they exert their effect. We performed allosteric pathway analysis based on molecular dynamics simulations and combined it with biochemical experiments to investigate the autoinhibition of PP2A. In the wild type (WT), the C-arm of the regulatory subunit B56δ obstructs the active and substrate binding sites exerting a dual autoinhibition effect. We find that the disease mutant, E198K, severely weakens the allosteric pathways that stabilize the C-arm in the WT. Instead, the strongest allosteric pathways in E198K take a different route that promotes exposure of the substrate binding site. To facilitate the allosteric pathway analysis, we introduce a path clustering algorithm for lumping pathways into channels. We reveal remarkable similarities between the allosteric channels of E198K and those in phosphorylation-activated WT, suggesting that the autoinhibition can be alleviated through a conserved mechanism. In contrast, we find that another disease mutant, E200K, which is in spatial proximity of E198, does not repartition the allosteric pathways leading to the substrate binding site; however, it may still induce exposure of the active site. This finding agrees with our biochemical data, allowing us to predict the activity of PP2A with the phosphorylated B56δ and provide insight into how disease mutations in spatial proximity alter the enzymatic activity in surprisingly different mechanisms.


Assuntos
Proteína Fosfatase 2 , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/química , Proteína Fosfatase 2/metabolismo , Fosforilação/genética , Domínios Proteicos , Mutação , Ligação Proteica
6.
bioRxiv ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37066309

RESUMO

An increasing number of mutations associated with devastating human diseases are diagnosed by whole-genome/exon sequencing. Recurrent de novo missense mutations have been discovered in B56δ (encoded by PPP2R5D), a regulatory subunit of protein phosphatase 2A (PP2A), that cause intellectual disabilities (ID), macrocephaly, Parkinsonism, and a broad range of neurological symptoms. Single-particle cryo-EM structures show that the PP2A-B56δ holoenzyme possesses closed latent and open active forms. In the closed form, the long, disordered arms of B56δ termini fold against each other and the holoenzyme core, establishing dual autoinhibition of the phosphatase active site and the substrate-binding protein groove. The resulting interface spans over 190 Šand harbors unfavorable contacts, activation phosphorylation sites, and nearly all residues with ID-associated mutations. Our studies suggest that this dynamic interface is close to an allosteric network responsive to activation phosphorylation and altered globally by mutations. Furthermore, we found that ID mutations perturb the activation phosphorylation rates, and the severe variants significantly increase the mitotic duration and error rates compared to the wild variant.

7.
J Environ Manage ; 339: 117913, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37060697

RESUMO

The development of social economy often requires a large consumption of water resources, and will also discharge a large amount of pollutants to the environment. Currently, the rapid development of regional water resources, social economy and ecological environment (WSE) complex system encounters significant challenges, and the coordination development of WSE complex system becomes important and necessary condition of regional sustainable development. Therefore, to scientifically evaluate the coordination development state of WSE system, based on the establishment of evaluation index system, the connection number and distance coordination model coupling approach for the coordination development evaluation of WSE complex system was proposed in this manuscript. The application results of the proposed method in Anhui Province, China indicate that, during 2011-2020, the coordination level of Anhui province is relatively high, and the coordination grade of most cities are in grade I or II. The coordination development degree of Anhui province presented a distinct improving trend with time, from most cities in grade IV or V in 2011 to most cities in grade II in 2020, from the worst 0.0580 in 2011 to the best 0.9200 in 2020. In terms of space, the coordinated development level of southern Anhui is higher than that of northern Anhui. Meanwhile, the coordination development status of the 16 cities in Anhui province can be divided into three patterns according to its historical variation characteristics, i.e., coordination development mode, ecological environment backward mode, and social and economic backward mode. Compared with the commonly used coordination evaluation method, the method of this paper can solve the problem of homogenization, and its calculation results are more reasonable and practical.


Assuntos
Conservação dos Recursos Naturais , Recursos Hídricos , Desenvolvimento Econômico , Ecossistema , Desenvolvimento Sustentável , Cidades , China
8.
Entropy (Basel) ; 25(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36832548

RESUMO

Currently, the implementation of water resource spatial equilibrium strategy is a fundamental policy of water resource integrated management in China; it is also a considerable challenge to explore the relationship structure features of water resources, society, economy and ecological environment (WSEE) complex system. For this purpose, firstly, we applied information entropy, ordered degree and connection number coupling method to reveal the membership characteristics between different evaluation indicators and grade criterion. Secondly, the system dynamics approach was introduced to describe the relationship features among different equilibrium subsystems. Finally, the ordered degree, connection number, information entropy and system dynamics integrated model was established to conduct relationship structure simulation and evolution trend evaluation of the WSEE system. The application results in Hefei city, Anhui Province, China, demonstrated that: (1) the variation of overall equilibrium conditions of WSEE system in Hefei city, 2020-2029 was higher compared to that of 2010-2019, though the increasing rate of ordered degree and connection number entropy (ODCNE) became slower after 2019; and (2) the annual ODCNE value from 2020 to 2029 of WSEE system under dry year scenarios increased about 0.0812, which indicated that the construction of Yangtze-Huaihe Diversion (YHD) project could play significant positive role in mitigating the equilibrium situation of WSEE system in Hefei city in the future. On the whole, this study is capable of providing the guidance basis for constructing a theoretical framework of structure simulation and equilibrium evaluation analysis of WSEE complex system.

9.
Cell ; 186(1): 80-97.e26, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36608661

RESUMO

Glucose is a universal bioenergy source; however, its role in controlling protein interactions is unappreciated, as are its actions during differentiation-associated intracellular glucose elevation. Azido-glucose click chemistry identified glucose binding to a variety of RNA binding proteins (RBPs), including the DDX21 RNA helicase, which was found to be essential for epidermal differentiation. Glucose bound the ATP-binding domain of DDX21, altering protein conformation, inhibiting helicase activity, and dissociating DDX21 dimers. Glucose elevation during differentiation was associated with DDX21 re-localization from the nucleolus to the nucleoplasm where DDX21 assembled into larger protein complexes containing RNA splicing factors. DDX21 localized to specific SCUGSDGC motif in mRNA introns in a glucose-dependent manner and promoted the splicing of key pro-differentiation genes, including GRHL3, KLF4, OVOL1, and RBPJ. These findings uncover a biochemical mechanism of action for glucose in modulating the dimerization and function of an RNA helicase essential for tissue differentiation.


Assuntos
RNA Helicases DEAD-box , Glucose , Queratinócitos , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , RNA Helicases DEAD-box/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Glucose/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Humanos
10.
Elife ; 112022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35924897

RESUMO

Protein phosphatase 2A (PP2A) holoenzymes target broad substrates by recognizing short motifs via regulatory subunits. PP2A methylesterase 1 (PME-1) is a cancer-promoting enzyme and undergoes methylesterase activation upon binding to the PP2A core enzyme. Here, we showed that PME-1 readily demethylates different families of PP2A holoenzymes and blocks substrate recognition in vitro. The high-resolution cryoelectron microscopy structure of a PP2A-B56 holoenzyme-PME-1 complex reveals that PME-1 disordered regions, including a substrate-mimicking motif, tether to the B56 regulatory subunit at remote sites. They occupy the holoenzyme substrate-binding groove and allow large structural shifts in both holoenzyme and PME-1 to enable multipartite contacts at structured cores to activate the methylesterase. B56 interface mutations selectively block PME-1 activity toward PP2A-B56 holoenzymes and affect the methylation of a fraction of total cellular PP2A. The B56 interface mutations allow us to uncover B56-specific PME-1 functions in p53 signaling. Our studies reveal multiple mechanisms of PME-1 in suppressing holoenzyme functions and versatile PME-1 activities derived from coupling substrate-mimicking motifs to dynamic structured cores.


Assuntos
Proteína Fosfatase 2 , Microscopia Crioeletrônica , Desmetilação , Holoenzimas/metabolismo , Metilação , Proteína Fosfatase 2/metabolismo
11.
Entropy (Basel) ; 24(7)2022 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-35885096

RESUMO

To promote the application of entropy concepts in uncertainty analysis of water resources complex system, a quantitative evaluation and obstacle factor diagnosis model of agricultural drought disaster risk was proposed using connection number and information entropy. The results applied to Suzhou City showed that the agricultural drought disaster risks in Suzhou during 2007-2017 were all in middle-risk status, while it presented a decreasing trend from 2010. The information entropy values of the difference degree item bI were markedly lower than those of the difference degree b, indicating that bI provided more information in the evaluation process. Furthermore, the status of drought damage sensitivity and drought hazard were improved significantly. Nevertheless, high exposure to drought and weak drought resistance capacity seriously impeded the reduction of risk. Thus, the key to decreasing risk was to maintain the level of damage sensitivity, while the difficulties were to reduce exposure and enhance resistance. In addition, the percentage of the agricultural population, population density, and percentage of effective irrigation area were the main obstacle factors of risk and also the key points of risk control in Suzhou. In short, the results suggest that the evaluation and diagnosis method is effective and conducive to regional drought disaster risk management.

12.
Environ Res ; 212(Pt A): 113163, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35346656

RESUMO

The threshold level method for drought identification is challenging due to the problems of selection of drought index reflecting the drought process associated with water supply and demand as well as the underlying physical meaning of drought thresholds. The frequently used hydrological drought indices (e.g., runoff) are susceptible to being affected by human activities, and drought characteristics are incapable of revealing spatial and temporal comparability. Furthermore, the drought process with the same severity but a longer duration is more likely to be evaluated as a more severe event, which contradicts the actual drought situation. In this study, the Palmer drought severity index (PDSI) method, in which the meteorological factors less influenced by human activities were taken as the input, was adopted to determine the dry/wet states and the PDSI value at each period firstly. The dry/wet states were defined with dry period, wet period, transition period, transition period in dry spell, and transition period in a wet spell. Following that, drought identification criteria were established through the dry/wet states and PDSI value according to the consistency of the identified results and the actual drought situations. Particularly, drought severity and peak intensity were taken as drought characteristics in this paper, and the joint return periods of the characteristics were estimated based on the Gumbel-Hougaard copula function. And eventually, a case study was conducted in Huaibei Plain, China. The results showed that the most severe droughts identified by PDSI had a good consistency with the actual drought situations, drought severity and peak intensity were applicable to reflect the drought impacts. It is worth noting that the implications of the joint return period and the relationships among different types of them. The occurrence probability of a multi-characteristic drought event should be calculated by the integration of joint probability density function over the region corresponding to the event of interest, and the joint frequency of drought characteristics should not be used as the occurrence probability of the drought disaster losses greater (or less) than that caused by the drought with the same characteristics. In addition, drought processes identified by PDSI and standardized precipitation indices (SPI) from monthly and seasonal scales were compared, indicating the drought identified results through PDSI are almost consistent with the actual situations.


Assuntos
Desastres , Secas , China , Demografia , Humanos , Hidrologia
13.
Nat Cancer ; 3(1): 43-59, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121987

RESUMO

Metastatic breast cancer is a leading health burden worldwide. Previous studies have shown that metadherin (MTDH) promotes breast cancer initiation, metastasis and therapy resistance; however, the therapeutic potential of targeting MTDH remains largely unexplored. Here, we used genetically modified mice and demonstrate that genetic ablation of Mtdh inhibits breast cancer development through disrupting the interaction with staphylococcal nuclease domain-containing 1 (SND1), which is required to sustain breast cancer progression in established tumors. We performed a small-molecule compound screening to identify a class of specific inhibitors that disrupts the protein-protein interaction (PPI) between MTDH and SND1 and show that our lead candidate compounds C26-A2 and C26-A6 suppressed tumor growth and metastasis and enhanced chemotherapy sensitivity in preclinical models of triple-negative breast cancer (TNBC). Our results demonstrate a significant therapeutic potential in targeting the MTDH-SND1 complex and identify a new class of therapeutic agents for metastatic breast cancer.


Assuntos
Endonucleases/metabolismo , Proteínas de Membrana/metabolismo , Nuclease do Micrococo , Proteínas de Ligação a RNA/metabolismo , Neoplasias de Mama Triplo Negativas , Animais , Moléculas de Adesão Celular/genética , Humanos , Proteínas de Membrana/genética , Camundongos , Proteínas de Ligação a RNA/genética , Fatores de Transcrição
14.
Environ Res ; 210: 112913, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35151656

RESUMO

The comprehensive evaluation analysis of water resource spatial equilibrium (WRSE) system is a fundamental and crucial facet to construct national water resource network system and implement socio-economy equilibrium development strategy in China. To clearly understanding of the structural relationship of WRSE system, we firstly proposed the definition of WRSE system from the perspective of coordination variation between water resource carrying pressure and support force subsystems in this study, then, the multi-dimensional connection cloud and coupling coordination degree approaches were applied to construct integrated evaluation model (MCCD) of WRSE system, and finally, the obstacle degree model was utilized as well to recognize the primary influence factors which resulted in the variation of WRSE system. Eventually, it can be revealed from the application results of MCCD model that, the overall situation of WRSE system in Anhui Province, China was improved obviously during the past 10 years, with the average coupling coordination degree (CCD) increased from 0.58 in 2011 to 0.68 in 2018. In addition, water resources availability per capita (S1) and agricultural irrigation quota (P8) were the two primary indicators causing the variation of water resource carrying support and pressure force subsystems. The above application analysis results were reliable and consistent with the evolution trend of actual historical observed statistics, and could also provide scientific decision-making basis for the implementation of prediction and regulation schemes of WRSE system.


Assuntos
Conservação dos Recursos Naturais , Recursos Hídricos , China , Cidades , Desenvolvimento Econômico , Análise Fatorial
15.
J Biol Chem ; 297(1): 100908, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34171357

RESUMO

The cAMP response element-binding protein (CREB) is an important regulator of cell growth, metabolism, and synaptic plasticity. CREB is activated through phosphorylation of an evolutionarily conserved Ser residue (S133) within its intrinsically disordered kinase-inducible domain (KID). Phosphorylation of S133 in response to cAMP, Ca2+, and other stimuli triggers an association of the KID with the KID-interacting (KIX) domain of the CREB-binding protein (CBP), a histone acetyl transferase (HAT) that promotes transcriptional activation. Here we addressed the mechanisms of CREB attenuation following bursts in CREB phosphorylation. We show that phosphorylation of S133 is reversed by protein phosphatase 2A (PP2A), which is recruited to CREB through its B56 regulatory subunits. We found that a B56-binding site located at the carboxyl-terminal boundary of the KID (BS2) mediates high-affinity B56 binding, while a second binding site (BS1) located near the amino terminus of the KID mediates low affinity binding enhanced by phosphorylation of adjacent casein kinase (CK) phosphosites. Mutations that diminished B56 binding to BS2 elevated both basal and stimulus-induced phosphorylation of S133, increased CBP interaction with CREB, and potentiated the expression of CREB-dependent reporter genes. Cells from mice harboring a homozygous CrebE153D mutation that disrupts BS2 exhibited increased S133 phosphorylation stoichiometry and elevated transcriptional bursts to cAMP. These findings provide insights into substrate targeting by PP2A holoenzymes and establish a new mechanism of CREB attenuation that has implications for understanding CREB signaling in cell growth, metabolism, synaptic plasticity, and other physiologic contexts.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteína Fosfatase 2/química , Animais , Sítios de Ligação , Células Cultivadas , Células HeLa , Humanos , Camundongos , Fosforilação , Ligação Proteica , Proteína Fosfatase 2/metabolismo , Transdução de Sinais , Ativação Transcricional
16.
Sci Total Environ ; 779: 146533, 2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34030269

RESUMO

The establishment of comprehensive drought index is a fundamental task for the analysis of drought hazard system evolution. To fully explore the characteristics of drought variation process, the cloud uncertainty reasoning method was applied to construct comprehensive drought index integrating precipitation with soil moisture indicators. The application results of the proposed drought index in Anhui Province, China revealed that, (1) The overall drought evolution presented significant intensifying trend with the drought occurrence frequency increasing from 32% to 41% from south to north in Anhui Province, and the primary drought type in the northern area was moderate-level drought events and above, while the drought type in the central and southern region was dominated by light-level drought events. (2) Autumn drought was the dominant type from 1960 to 2007 in Anhui Province, with the average drought occurrence frequency of 40%. In addition, the evolution of spring and autumn drought all presented intensifying trends from 1960 to 2007, while the summer and winter drought evolution trends were opposite. (3) The Mann-Kendall trend test results revealed that the drought evolution presented evidently intensifying trend from August 1967 to February 1969, but slight declining trend from May 1974 to August 1978, July 1989 to August 2001 and February 2003 to December 2007, and the mutation of drought evolution occurred in November 1972, February 1978 and August 1998, etc. The above results were basically consistent with the historical statistics, indicating that the proposed comprehensive drought index and its construction framework were reliable, which can be further applied in the related research field of regional drought risk management.

17.
Chinese Journal of School Health ; (12): 1768-1771, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-906801

RESUMO

Objective@#To understand the current situation of school tuberculosis prevention and control system and the implementation of daily prevention and control measures, and to provide a reference for strengthening the prevention and control of tuberculosis in schools.@*Methods@#A random sampling method was used to select schools where on site questionnaire survey was carried out, including 156 junior high schools, 78 senior high schools and 6 universities. SPSS 25.0 was used for descriptive analysis and chi square test.@*Results@#The average annual screening rates of junior high school, senior high school and university from 2015 to 2020 were 58.84%, 71.71% and 84.41% respectively, and the difference was statistically significant ( χ 2=61 247.39, P <0.01). The average annual TB detection rates were 8.69/10 5, 50.89/10 5 and 36.51/10 5 respectively, and the difference was statistically significant ( χ 2=101.20, P <0.01). The screening rate of TB screening in 2015-2020 years increased by year( χ 2 trend =70 052.10, 86 182.82 , 22 213.56, P <0.01). The detection rate of TB among junior high schools and high schools has been increasing year by year( χ 2 trend =9.27, 12.23, P <0.01). From 2015 to 2020, the proportion of tuberculosis screening, contact history, PPD and chest screening increased by year in junior high school and senior high school freshmen, and the difference was statistically significant ( χ 2=129.10, 118.10, 206.92, 37.67; 108.79, 84.90, 139.84, 51.82, P <0.01). The proportion of chest X ray screening in universities increased by year( χ 2 trend =18.33, P <0.01). In 2019, poor performance on TB control in universities mainly included, including the school responsibility system for tuberculosis prevention and control, the school s annual TB work plan and absenteeism registration and etiology tracing, the proportion was 50.00 %, 0 and 16.67% respectively, compared with junior high school and senior high school, the difference was statistically significant( P <0.05). The prevalence rates of junior high school, senior high school and university students were 33.75/10 5, 90.10/10 5 and 54.20/10 5 respectively in 2019, and the difference was statistically significant ( χ 2=104.36, P <0.01).@*Conclusion@#The proportion of TB screening for freshmen in Chongqing increased significantly during 2015- 2020. High school students are still the focus of school based tuberculosis prevention and control. Improving the proportion of tuberculosis screening,strengthening and standardizing physical examination and screening,and establishing a clear responsibility system for prevention and control are effective means to prevent and control the spread of tuberculosis on campus.

18.
Entropy (Basel) ; 22(1)2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-33285881

RESUMO

Drought is one of the most typical and serious natural disasters, which occurs frequently in most of mainland China, and it is crucial to explore the evolution characteristics of drought for developing effective schemes and strategies of drought disaster risk management. Based on the application of Cloud theory in the drought evolution research field, the cloud transformation algorithm, and the conception zooming coupling model was proposed to re-fit the distribution pattern of SPI instead of the Pearson-III distribution. Then the spatio-temporal evolution features of drought were further summarized utilizing the cloud characteristics, average, entropy, and hyper-entropy. Lastly, the application results in Northern Anhui province revealed that the drought condition was the most serious during the period from 1957 to 1970 with the SPI12 index in 49 months being less than -0.5 and 12 months with an extreme drought level. The overall drought intensity varied with the highest certainty level but lowest stability level in winter, but this was opposite in the summer. Moreover, drought hazard would be more significantly intensified along the elevation of latitude in Northern Anhui province. The overall drought hazard in Suzhou and Huaibei were the most serious, which is followed by Bozhou, Bengbu, and Fuyang. Drought intensity in Huainan was the lightest. The exploration results of drought evolution analysis were reasonable and reliable, which would supply an effective decision-making basis for establishing drought risk management strategies.

19.
BMC Infect Dis ; 20(1): 531, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698763

RESUMO

BACKGROUND: China is a country with a high burden of pulmonary tuberculosis (PTB). Chongqing is in the southwest of China, where the notification rate of PTB ranks tenth in China. This study analyzed the temporal and spatial distribution characteristics of PTB in Chongqing in order to improve TB control measures. METHODS: A spatial-temporal analysis has been performed based on the data of PTB from 2011 to 2018, which was extracted from the National Surveillance System. The effect of TB control was measured by variation trend of pathogenic positive PTB notification rate and total TB notification rate. Time series, spatial autonomic correlation and spatial-temporal scanning methods were used to identify the temporal trends and spatial patterns at county level. RESULTS: A total of 188,528 cases were included in this study. A downward trend was observed in PTB between 2011 and 2018 in Chongqing. The peak of PTB notification occurred in late winter and early spring annually. By calculating the value of Global Moran's I and Local Getis's Gi*, we found that PTB was spatially clustered and some significant hot spots were detected in the southeast and northeast of Chongqing. One most likely cluster and three secondary clusters were identified by Kulldorff's scan spatial-temporal Statistic. CONCLUSIONS: This study identified seasonal patterns and spatial-temporal clusters of PTB cases in Chongqing. Priorities should be given to southeast and northeast of Chongqing for better TB control.


Assuntos
Monitoramento Epidemiológico , Análise Espaço-Temporal , Tuberculose Pulmonar/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , China/epidemiologia , Análise por Conglomerados , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estações do Ano , Tuberculose Pulmonar/microbiologia , Adulto Jovem
20.
Sci Total Environ ; 710: 136324, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923681

RESUMO

Water resource carrying capacity modelling is a fundamental task to explore the interaction mechanism between socio-economic development and water resource carrying system. To reasonably quantify regional water resource carrying capacity, firstly, the water resource carrying system was divided into pressure, support and regulation forces subsystems, then the multi-dimensional precondition cloud algorithm was introduced to quantify the belonging degree of single evaluation index, and the comprehensive belonging degree of each sample was further obtained through risk matrix and index weight, and finally the multi-dimensional precondition cloud and risk matrix coupling model (PCRM) was established to recognize carrying grade and reveal carrying mechanism. The application results of PCRM model indicated that water resource carrying capacity in Anhui province, China presented a slightly improving trend in both provincial and city scales during 2005 to 2015. Meanwhile, evaluation result of PCRM model was more approaching to the average characteristic value of different approaches, which indicated that PCRM coupling model is effectively to explore properties of indexes and subsystems of water resource carrying system, and could be further applied in other system evaluation and regulation research fields in the future.

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