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BACKGROUND: Robotic gastrectomy (RG) has been widely used to treat gastric cancer. However, whether the short-term outcomes of robotic gastrectomy are superior to those of laparoscopic gastrectomy (LG) for elderly patients with advanced gastric cancer has not been reported. METHODS: The study enrolled of 594 elderly patients with advanced gastric cancer who underwent robotic or laparoscopic radical gastrectomy. The RG cohort was matched 1:3 with the LG cohort using propensity score-matching (PSM). RESULTS: After PSM, 121 patients were included in the robot group and 363 patients in the laparoscopic group. Excluding the docking and undocking times, the operation time of the two groups was similar (P = 0.617). The RG group had less intraoperative blood loss than the LG group (P < 0.001). The time to ambulation and first liquid food intake was significantly shorter in the RG group than in the LG group (P < 0.05). The incidence of postoperative complications did not differ significantly between the two groups (P = 0.14). Significantly more lymph nodes were dissected in the RG group than in the LG group (P = 0.001). Postoperative adjuvant chemotherapy was started earlier in the RG group than in the LG group (P = 0.02). CONCLUSIONS: For elderly patients with advanced gastric cancer, RG is safe and feasible. Compared with LG, RG is associated with less intraoperative blood loss; a faster postoperative recovery time, allowing a greater number of lymph nodes to be dissected; and earlier adjuvant chemotherapy.
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Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Neoplasias Gástricas , Humanos , Idoso , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Pontuação de Propensão , Perda Sanguínea Cirúrgica , Resultado do Tratamento , Gastrectomia , Complicações Pós-Operatórias/cirurgia , Estudos RetrospectivosRESUMO
The comorbidity of autism spectrum disorder and anxiety is common, but the underlying circuitry is poorly understood. Here, Tmem74-/- mice showed autism- and anxiety-like behaviors along with increased excitability of pyramidal neurons (PNs) in the prelimbic cortex (PL), which were reversed by Tmem74 re-expression and chemogenetic inhibition in PNs of the PL. To determine the underlying circuitry, we performed conditional deletion of Tmem74 in the PNs of PL of mice, and we found that alterations in the PL projections to fast-spiking interneurons (FSIs) in the dorsal striatum (dSTR) (PLPNs-dSTRFSIs) mediated the hyperexcitability of FSIs and autism-like behaviors and that alterations in the PL projections to the PNs of the basolateral amygdaloid nucleus (BLA) (PLPNs-BLAPNs) mediated the hyperexcitability of PNs and anxiety-like behaviors. However, the two populations of PNs in the PL had different spatial locations, optogenetic manipulations revealed that alterations in the activity in the PL-dSTR or PL-BLA circuits led to autism- or anxiety-like behaviors, respectively. Collectively, these findings highlight that the hyperactivity of the two populations of PNs in the PL mediates autism and anxiety comorbidity through the PL-dSTR and PL-BLA circuits, which may lead to the development of new therapeutics for the autism and anxiety comorbidity.
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Transtorno do Espectro Autista , Transtorno Autístico , Complexo Nuclear Basolateral da Amígdala , Camundongos , Animais , Transtorno Autístico/genética , Transtorno do Espectro Autista/genética , Córtex Cerebral , Ansiedade , Córtex Pré-FrontalRESUMO
Efficient and multiple CO2 utilization into high-value-added chemicals holds significant importance in carbon neutrality and industry production. However, most catalysis systems generally exhibit only one type of CO2 transformation with the efficiency to be improved. The restricted abundance of active catalytic sites or an inefficient utilization rate of these sites results in the constraint. Consequently, we designed and constructed two metal hydrogen-bonded organic frameworks (M-HOFs) {[M3(L3-)2(H2O)10]·2H2O}n (M = Co (1), Ni (2); L = 1-(4-carboxyphenyl)-1H-pyrazole-3,5-dicarboxylic acid) in this research. 1 and 2 are well-characterized, and both show excellent stability. The networks connected by multiple hydrogen bonds enhance the structural flexibility and create accessible Lewis acidic sites, promoting interactions between the substrates and catalytic centers. This enhancement facilitates efficient catalysis for two types of CO2 transformations, encompassing both cycloaddition reactions with epoxides and aziridines to afford cyclic carbonates and oxazolidinones. The catalytic activities (TON/TOF) are superior compared with those of most other catalysts. These heterogeneous catalysts still exhibited high performance after being reused several times. Mechanistic studies indicated intense interactions between the metal sites and substrates, demonstrating the reason for efficient catalysis. This marks the first instance on M-HOFs efficiently catalyzing two types of CO2 conversions, finding important significance for catalyst design and CO2 utilization.
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BACKGROUND: The role of minimally invasive surgery using robotics versus laparoscopy in resectable gastric cancer patients with a high body mass index (BMI) remains controversial. METHODS: A total of 482 gastric adenocarcinoma patients with BMI ≥ 25 kg/m2 who underwent minimally invasive radical gastrectomy between August 2016 and December 2019 were retrospectively analyzed, including 109 cases in the robotic gastrectomy (RG) group and 321 cases in the laparoscopic gastrectomy (LG) group. Propensity score matching (PSM) with a 1:1 ratio was performed, and the perioperative outcomes, lymph node dissection, and 3-year overall survival (OS) and disease-free survival (DFS) rates were compared. RESULTS: After PSM, 109 patients were included in each of the RG and LG groups, with balanced baseline characteristics. Compared with the LG group, the RG group had similar intraoperative estimated blood loss [median (IQR) 30 (20-50) vs. 35 (30-59) mL, median difference (95%CI) - 5 (- 10 to 0)], postoperative complications [13.8% vs. 18.3%, OR (95%CI) 0.71 (0.342 to 1.473)], postoperative recovery, total harvested lymph nodes [(34.25 ± 13.43 vs. 35.44 ± 14.12, mean difference (95%CI) - 1.19 (- 4.871 to 2.485)] and textbook outcomes [(81.7% vs. 76.1%, OR (95%CI) 1.39 (0.724 to 2.684)]. Among pathological stage II-III patients receiving chemotherapy, the initiation of adjuvant chemotherapy in the RG group was similar to that in the LG group [median (IQR): 28 (25.5-32.5) vs. 32 (27-38.5) days, median difference (95%CI) - 3 (- 6 to 0)]. The 3-year OS (RG vs. LG: 80.7% vs. 81.7%, HR = 1.048, 95%CI 0.591 to 1.857) and DFS (78% vs. 76.1%, HR = 0.996, 95%CI 0.584 to 1.698) were comparable between the two groups. CONCLUSION: RG conferred comparable lymph node dissection, postoperative recovery, and oncologic outcomes in a selected cohort of patients with BMI ≥ 25 kg/m2.
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Gastrectomia , Laparoscopia , Pontuação de Propensão , Procedimentos Cirúrgicos Robóticos , Neoplasias Gástricas , Humanos , Gastrectomia/métodos , Masculino , Procedimentos Cirúrgicos Robóticos/métodos , Feminino , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Laparoscopia/métodos , Sobrepeso/complicações , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Excisão de Linfonodo/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Intervalo Livre de DoençaRESUMO
BACKGROUND: Affective states, including sentiment and emotion, are critical determinants of health. However, few studies among men who have sex with men (MSM) have examined sentiment and emotion specifically using real-time social media technologies. Moreover, the explorations on their associations with sexual and health status among MSM are limited. OBJECTIVE: This study aimed to understand and examine the associations of affective states with sexual behaviors and health status among MSM using public data from the Blued (Blued International Inc) app. METHODS: A total of 843,745 public postings of 377,610 MSM users located in Guangdong were saved from the Blued app by automatic screen capture. Positive affect, negative affect, sexual behaviors, and health status were measured using the Simplified Chinese Linguistic Inquiry and Word Count. Emotions, including joy, sadness, anger, fear, and disgust, were measured using the Weibo Basic Mood Lexicon. A positive sentiment score and a positive emotion score were also calculated. Univariate and multivariate linear regression models on the basis of a permutation test were used to assess the associations of affective states with sexual behaviors and health status. RESULTS: A total of 5871 active MSM users and their 477,374 postings were finally selected. Both positive affect and positive emotions (eg, joy) peaked between 7 AM and 9 AM. Negative affect and negative emotions (eg, sadness and disgust) peaked between 2 AM and 4 AM. During that time, 25.1% (97/387) of negative postings were related to health and 13.4% (52/387) of negative postings were related to seeking social support. A multivariate analysis showed that the MSM who were more likely to post sexual behaviors were more likely to express positive affect (beta=0.3107; P<.001) and positive emotions (joy: beta=0.027; P<.001), as well as negative emotions (sadness: beta=0.0443; P<.001 and disgust: beta=0.0256; P<.001). They also had a higher positive sentiment score (beta=0.2947; P<.001) and a higher positive emotion score (beta=0.1612; P<.001). The MSM who were more likely to post their health status were more likely to express negative affect (beta=0.8088; P<.001) and negative emotions, including sadness (beta=0.0705; P<.001), anger (beta=0.0058; P<.001), fear (beta=0.0052; P<.001), and disgust (beta=0.3065; P<.001), and less likely to express positive affect (beta=-0.0224; P=.02). In addition, they had a lower positive sentiment score (beta=-0.8306; P<.001) and a lower positive emotion score (beta=-0.3743; P<.001). CONCLUSIONS: The MSM social media community mainly expressed their positive affect in the early morning and negative affect after midnight. Positive affective states were associated with being sexually active, whereas negative affective states were associated with health problems, mostly about mental health. Our finding suggests the potential to deliver different health-related intervention strategies (eg, psychological counseling and safe sex promotion) on a social media app according to the affective states of MSM in real time.
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Homossexualidade Masculina/psicologia , Comportamento Sexual/psicologia , Mídias Sociais/normas , Adulto , China , Humanos , MasculinoRESUMO
[This corrects the article DOI: 10.2196/13201.].
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PURPOSE: The purpose of this study was to investigate the maxillofacial morphologic characteristics of children with complete unilateral cleft lip and palate (UCLP) with and without surgical correction and better understand the relation between surgery and inhibition of maxillary growth. MATERIAL AND METHODS: Lateral cephalometric radiography was performed in 3 groups of 9-year-old children: 1) 20 whose UCLP was repaired in infancy; 2) 20 who had no surgical repair or any relevant treatments; and 3) 20 without UCLP who served as controls. RESULTS: Marked morphologic deviations of patients in groups 1 and 2 compared with the control group were observed in the cranial base angle, maxillary heights, length and shape of the mandible, and anteroposterior jaw relation. Facial morphology was similar between groups 1 and 2 except for less vertical maxillary height and more obtuse gonial angle in group 1. CONCLUSION: The facial morphology of children with UCLP differs markedly from that of normal children. The differences can be ascribed to the difference in the primary anomaly in the UCLP groups, but isolated surgery has minor effects on growth disturbances.
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Fenda Labial/cirurgia , Fissura Palatina/cirurgia , Desenvolvimento Maxilofacial , Transplante Ósseo , Estudos de Casos e Controles , Cefalometria , Criança , China , Fenda Labial/diagnóstico por imagem , Fissura Palatina/diagnóstico por imagem , Feminino , Humanos , Masculino , Estudos RetrospectivosRESUMO
AIM: Epigallocatechin-3-gallate (EGCG) is a major polyphenol in green tea. In this study, we investigated the effects of EGCG on insulin resistance and insulin clearance in non-alcoholic fatty liver disease (NAFLD) mice. METHODS: Mice were fed on a high-fat diet for 24 weeks. During the last 4 weeks, the mice were injected with EGCG (10, 20 and 40 mg·kg(-1)·d(-1), ip). Glucose tolerance, insulin tolerance and insulin clearance were assessed. After the mice were euthanized, blood samples and tissue specimens were collected. Glucose-stimulated insulin secretion was examined in isolated pancreatic islets. The progression of NAFLD was evaluated histologically and by measuring lipid contents. Insulin-degrading enzyme (IDE) protein expression and enzyme activity were detected using Western blot and immunocapture activity assays, respectively. RESULTS: The high-fat diet significantly increased the body weight and induced grade 2 or 3 liver fatty degeneration (steatosis, lobular inflammation and ballooning) accompanied by severe hyperlipidemia, hyperglycemia, hyperinsulinemia and insulin resistance in the model mice. Administration of EGCG dose-dependently ameliorated the hepatic morphology and function, reduced the body weight, and alleviated hyperlipidemia, hyperglycemia, hyperinsulinemia and insulin resistance in NAFLD mice. Furthermore, EGCG dose-dependently enhanced insulin clearance and upregulated IDE protein expression and enzyme activity in the liver of NAFLD mice. CONCLUSION: EGCG dose-dependently improves insulin resistance in NAFLD mice not only by reducing body weight but also through enhancing the insulin clearance by hepatic IDE. The results suggest that IDE be a potential drug target for the treatment of NAFLD.
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Camellia sinensis , Catequina/análogos & derivados , Hipoglicemiantes/farmacologia , Resistência à Insulina , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Catequina/farmacologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Insulina/sangue , Insulisina/metabolismo , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Fitoterapia , Plantas Medicinais , Fatores de TempoRESUMO
Ganglion cysts are common pseudocystic masses, whereas those arising from the temporomandibular joint (TMJ) are rare entities. We report a case of ganglion cyst of the right TMJ with symptomatic bilateral TMJ internal derangement in a 24-year-old man. Disk repositioning using bone anchors and excision of the ganglion cyst were performed. A unique characteristic of inflammatory infiltrates was revealed in the specimen, and the relationship between these 2 distinct entities and probable pathogenesis of infectious involvement are discussed.
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Cistos Glanglionares/cirurgia , Cisto Sinovial/cirurgia , Transtornos da Articulação Temporomandibular/cirurgia , Síndrome da Disfunção da Articulação Temporomandibular/cirurgia , Cistos Glanglionares/diagnóstico , Cistos Glanglionares/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Âncoras de Sutura , Cisto Sinovial/diagnóstico , Cisto Sinovial/patologia , Articulação Temporomandibular/cirurgia , Disco da Articulação Temporomandibular/cirurgia , Transtornos da Articulação Temporomandibular/diagnóstico , Transtornos da Articulação Temporomandibular/patologia , Síndrome da Disfunção da Articulação Temporomandibular/diagnóstico , Síndrome da Disfunção da Articulação Temporomandibular/patologia , Adulto JovemRESUMO
Studying the spatiotemporal variation in vegetation net primary productivity (NPP) and exploring its influencing factors are of considerable practical significance for understanding the spatiotemporal variation in vegetation and for guiding ecological restoration and management projects based on local conditions. Based on MODIS NPP data, combined with in situ meteorological data, land use data, and vegetation type data, this study explores the spatiotemporal variation in different types of vegetation NPP in southwest China via the Mann-Kendall significance test and Theil-Sen Median slope estimator. It reveals the influencing factors of spatial differentiation of different types of vegetation NPP and the interaction between influencing factors in combination with stability analysis and Geo Detectors. The results revealed that on the temporal scale, from 2000 to 2021, vegetation NPP, NPPPre (vegetation NPP exclusively under the influence of climate change), and NPPRes (vegetation NPP exclusively under the influence of human activities) in southwest China showed a fluctuating upward trend. Among different vegetation types, NPP, NPPPre, and NPPRes exhibited an upward trend, except for a minor decline in NPPRes of tree vegetation at a rate of -0.183 g·(m2·a)-1. Among them, NPP, NPPPre, and NPPRes of economic vegetation showed the most significant upward rates, 5.96, 3.09, and 2.94 g·(m2·a)-1, respectively. On the spatial scale, the tree vegetation NPP with the most significant downward trend was mainly distributed in Tibet and southern Yunnan, while the economic vegetation NPP with the highest upward trend was primarily distributed in eastern Sichuan Province. The stability of vegetation NPP in southwest China presented a spatial distribution pattern of "low in the south and high in the north," and the average value of the correlation coefficient increased in the ascending order of arbor vegetation (0.101), shrub vegetation (0.105), herb vegetation (0.110), and economic vegetation (0.114). The interaction between surface temperature and relative humidity was the main influencing factor for spatial differentiation of vegetation NPP, while the interaction between sunshine duration and warmth index had the most significant impact on vegetation in southwest China, with an increasing percentage of 30.91%. Different types of vegetation had different requirements for different climatic factors, but their requirements for surface temperature and warmth index were significantly consistent. When the surface temperature was 21.03-28.49â, and the warmth index was 106.46-167.2, the NPP of different vegetation types peaked. Under natural succession, the impact of climate change on vegetation was inversely proportional to the stability of the vegetation community. The arbor vegetation community with high stability was less affected, while the herb vegetation community with low stability was highly affected by climate. In contrast, the stability of economic vegetation was directly proportional to the impact of climate due to the influence of human activities. This study establishes a theoretical foundation for evaluating the impact of regional climate on the growth of different vegetation types and can be crucial for formulating ecological restoration and management strategies in southwest China that are adapted to the local conditions.
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Ecossistema , Modelos Teóricos , Humanos , China , Tibet , Temperatura , Mudança ClimáticaRESUMO
Quantitatively determining the direct, indirect, and comprehensive effects of climatic factors on the growing season of the vegetation GPP (GPPGS) in the middle and lower reaches of the Yangtze River at the regional and vegetation type scales can provide a scientific basis for the management and restoration of regional vegetation resources under the background of global climate change. Using MODIS GPP data, meteorological data, and vegetation type data, combined with Theil-Sen Median trend analysis and the Mann-Kendall significance test, the spatiotemporal characteristics of the GPPGS in the middle and lower reaches of the Yangtze River were investigated at different temporal and spatial scales. Path analysis was used to further reveal the direct, indirect, and comprehensive effects of climate factors on GPPGS variation in different vegetation types. The results showed that:â from 2000 to 2021, the vegetation GPPGS in the middle and lower reaches of the Yangtze River showed a fluctuating upward trend, with a rising rate (in terms of C, same below) of 2.70 g·(m2·a)-1 (P<0.01). The GPPGS of different vegetation types all showed a significant upward trend (P<0.01), with shrubs having the highest upward rate of 3.31 g·(m2·a)-1 and cultivated vegetation having the lowest upward rate of 2.54 g·(m2·a)-1. â¡ The proportion of the area with an upward trend in GPPGS in the middle and lower reaches of the Yangtze River was 88.11%. The proportion of the area with an upward trend in GPPGS was greater than 84% for all different vegetation types, with shrubs (49.76%) and cultivated vegetation (44.36%) having significantly higher proportions of the area with an upward trend than that in other vegetation types. ⢠The path analysis results showed that precipitation and the maximum temperature had a significant positive direct effect on vegetation GPPGS (P<0.05), whereas solar radiation had a non-significant positive effect (P ≥ 0.05). The indirect effects of maximum temperature, precipitation, and solar radiation on vegetation GPPGS were all non-significantly negative (P ≥ 0.05). Under the combined effects of direct and indirect influences, precipitation and maximum temperature had a non-significant positive effect on vegetation GPPGS (P ≥ 0.05), whereas solar radiation had a non-significant negative effect on vegetation GPPGS (P ≥ 0.05). Among different vegetation types, precipitation was the main climate factor affecting the changes in GPPGS of cultivated vegetation, whereas the maximum temperature was the main climate factor affecting the changes in GPPGS of coniferous forests, broad-leaved forests, shrubs, and grasslands. ⣠The changes in vegetation GPPGS in the middle and lower reaches of the Yangtze River were mainly influenced by the direct effects of maximum temperature, precipitation, and solar radiation, with the direct effect of precipitation dominating 56.72% of the changes in GPPGS. The research results can provide a reference for quantifying the carbon sequestration potential of vegetation in the middle and lower reaches of the Yangtze River and formulating ecological restoration governance policies tailored to local conditions under the background of global climate change.
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Mudança Climática , Ecossistema , Rios , Estações do Ano , Florestas , Temperatura , ChinaRESUMO
BACKGROUND: The effects of the dynamics of serum tumor markers (CA72-4, CEA, CA19-9, CA125 and AFP) before and after neoadjuvant chemotherapy (NACT) on the prognosis of gastric cancer(GC) patients remain unclear. METHODS: The training set contained 334 GC patients from Fujian Medical University Union Hospital (FJMUUH) and 113 GC patients in Qinghai University Affiliated Hospital (QhUAH) were used as an external validation set. Tumor marker regression load (ΔTMRL) indicator, including ΔCA72-4, ΔCEA, ΔCA19-9, ΔCA125, and ΔAFP, is defined as [(postNACT marker- preNACT marker)/preNACT marker]. Tumor marker regression load score (TMRLS) consists of ΔCA72-4, ΔCEA and ΔCA125. The predictive performance of the nomogram-TMRLS was evaluated using the area under the receiver operating characteristic(ROC) curve(AUC), decision curve analysis(DCA), and C-index. RESULTS: Patients from FJMUUH were divided into two groups, TMRLS-low and TMRLS-high, determined by R package maxstat. Survival analysis revealed a higher 3-year overall survival(OS) in the TMRLS-low than in the TMRLS-high group. The TMRLS-high group who received postoperative adjuvant chemotherapy(AC) showed a significantly higher 3-year OS rate than those who did not. Multivariate COX regression analysis indicated that TMRLS was an independent prognostic factor for OS. A nomogram for predicting OS based on TMRLS showed a significantly higher C-index and AUC than the ypTNM stage. The above results were also found in the QhUAH external validation cohort. CONCLUSION: TMRLS is a novel independent prognostic factor for GC who underwent NACT and a radical gastrectomy. Furthermore, the TMRLS-high group, who received postoperative AC, may achieve better survival outcomes. Notably, the predictive performance of the nomogram-TMRLS significantly outperformed that of the ypTNM stage.
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Antígenos Glicosídicos Associados a Tumores , Biomarcadores Tumorais , Gastrectomia , Terapia Neoadjuvante , Nomogramas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/cirurgia , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Biomarcadores Tumorais/sangue , Antígenos Glicosídicos Associados a Tumores/sangue , Antígeno Ca-125/sangue , Idoso , Antígeno Carcinoembrionário/sangue , Quimioterapia Adjuvante , Antígeno CA-19-9/sangue , Taxa de Sobrevida , Curva ROC , Estudos Retrospectivos , Adulto , alfa-FetoproteínasRESUMO
Vegetation net primary productivity (NPP) is an important parameter for evaluating the quality of terrestrial ecosystems. It is of great importance to study the spatio-temporal evolution of vegetation NPP and its driving force for regional ecological environment protection and sustainable development. On the basis of MODIS NPP data, meteorological data, DEM data, population density data, GDP data, and land use type data, this study used linear regression analysis, R/S analysis, and a Geodetector model to analyze the spatio-temporal variation in vegetation NPP and its future changing trend on both regional and landform scales and to detect the influencing factors that affect the spatial differentiation of vegetation NPP. The results showed that the vegetation NPP exhibited an extremely significant upward trend in southwest China from 2000 to 2020. On the landform scale, the vegetation NPP had showed an upward trend in all landforms, except for the southern Tibet Plateau; among them, the vegetation NPP in the Sichuan Basin showed the most obvious upward trend. The variation in vegetation NPP exhibited obvious spatial heterogeneity in southwest China, with the changing rate of "high in the east and low in the west." The areas with an upward trend of vegetation NPP were greater than the areas with a downward trend, but the changing trend was dominated by a decreasing trend in the future, both in southwest China and each landform unit. The Geodetector results showed that elevation was the dominant factor controlling the spatial differentiation of vegetation NPP in southwest China and all landform units, except for the Yunan-Guizhou Plateau, in which the spatial differentiation of vegetation NPP was mostly dominated by temperature. The interaction detection results showed that the interaction between the influencing factors was manifested as two-factor enhancement or nonlinear enhancement. The interaction between elevation and temperature showed the highest impact on vegetation NPP distribution. On the landform scale, the spatial differential of vegetation NPP was dominated by the interaction between elevation and climate factors or elevation and GDP in the Guangxi Hills, Sichuan Basin, Zoige Plateau, Hengduan Mountains, and southern Tibet Plateau and between climate factors in the Yunan-Guizhou Plateau. The above results indicated that vegetation NPP variation and the influencing factors that dominate its spatial differential in southwest China showed obvious scale effects. Therefore, exploring the dynamic variation in vegetation NPP and its influencing factors at different spatial scales has practical significance for a comprehensive understanding of the vegetation cover situation and formulating regional ecological restoration plans in southwest China.
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Ecossistema , Modelos Teóricos , China , Mudança Climática , TibetRESUMO
Studies on the spatio-temporal variation and driving mechanism of PM2.5 concentration in the Chengdu-Chongqing urban agglomeration are of great significance for regional atmospheric environment protection and national economic sustainable development. Based on PM2.5 remote sensing data, DEM data, in situ meteorological data, MODIS NDVI data, population density data, nighttime lighting data, road network data, and land use type data, a series of mathematical methods such as Theil-Sen Medium analysis and Mann-Kendall significance test, combined with the Geo-detector model were used to analyze the spatio-temporal variation and multi-dimensional detection of the driving mechanism of PM2.5 concentration in the Chengdu-Chongqing urban agglomeration. The results showed that the overall PM2.5 concentration showed a fluctuating downward trend in the Chengdu-Chongqing urban agglomeration from 2000 to 2021, and the PM2.5 pollution was the most prominent in winter. PM2.5 concentration exhibited obvious spatial heterogeneity with "high in the middle and low in the surrounding areas." The high-PM2.5 concentration areas were mainly concentrated in Zigong, Neijiang, Ziyang, and Guang'an, and the areas with a PM2.5 concentration decrease were mainly concentrated in the west of Chongqing. Influencing detection results showed that the spatial heterogeneity of PM2.5 concentration in the Chengdu-Chongqing urban agglomeration was influenced by the combined effects of climate factors, topographic factors, vegetation cover, and anthropogenic factors. Furthermore, elevation, slope, and road network density were regarded as the dominant factors influencing the spatial heterogeneity of PM2.5 concentration in the study area. Topographic factors and climate factors showed the highest and lowest contribution rate to the spatial heterogeneity of PM2.5 concentration, respectively. The contribution rate of topographic factors and anthropogenic factors had gradually increased, and the contribution rate of climate factors and vegetation cover had gradually decreased in the study area from 2000 to 2021. Interaction detection results showed that the spatial heterogeneity of PM2.5 concentration in the Chengdu-Chongqing urban agglomeration was mostly affected by the interaction effects of elevation and road network density, slope, precipitation, sunshine duration, and land use type. The interaction detection results exhibited obvious regional differences on the city level. For instance, the spatial heterogeneity of PM2.5 concentration in Chengdu, Deyang, and Leshan was mostly affected by the interaction between different influencing types, and the spatial heterogeneity of PM2.5 concentration in Dazhou, Meishan, Ya'an, Ziyang, Neijiang, and Zigong was mostly affected by the interaction within a single influencing type.
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Using the MOD13A3 NDVI time series from 2000 to 2020, climate date from 1999 to 2020, and land use type data in 2000 and 2020, the spatio-temporal variation in vegetation cover and the driving mechanisms of climate change and human activities to vegetation variation were analyzed based on Theil-Sen Median analysis, the Mann-Kendall significance test, the multi-collinearity test, residual analysis, and relative analysis. The results showed that the vegetation cover exhibited a fluctuating and increasing trend with a magnitude of 0.0016 a-1 in southwest China from 2000 to 2020. The increasing trend of vegetation cover was mostly significant in the Guangxi Hills and Yunnan-Guizhou Plateau and slightly significant in the Tibet Plateau. The vegetation cover had increased in the context of climate change and human activities, with an increasing rate of 0.0010 a-1 and 0.0006 a-1, respectively. The vegetation improvement was mostly dominated by the combination effects of climate change and human activities. The vegetation improvement was dominated by climate change, and the relative role of climate change reached 61.86%. What is more, the vegetation degradation was dominated by human activities, and the relative role of human activities reached 58.39%. Vegetation cover was positively related to minimum temperature, precipitation, maximum temperature, potential evapotranspiration rate, and relative humidity and negatively related to mean temperature, atmosphere pressure, sunshine duration, warmth index, and humidity index. As a whole, the minimum temperature, sunshine duration, and precipitation were the dominant climate factors affecting the vegetation variation in southwest China. Furthermore, the land use and land cover change were significantly related to vegetation variation in southwest China. The implementation of ecological afforestation projects could be beneficial to regional vegetation improvement, whereas the vegetation degradation was mostly conducted by the built-up land expansion.
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Condução de Veículo , Humanos , China , Tibet , Atividades Humanas , Mudança Climática , Temperatura , EcossistemaRESUMO
Studying the spatial-temporal variation in net primary productivity (NPP) in terrestrial vegetation ecosystems and its driving forces in southwest China is of great importance for regional eco-environmental protection. The spatial and temporal changes in net primary productivity (NPP) in terrestrial vegetation ecosystems and its responding characteristics to climate change and human activities were explored in this study on the basis of the Moderate Resolution Imaging Spectroradiometer (MODIS) NPP from 2000 to 2021, in situ meteorological data from 1999 to 2021, and land use type datasets from 2000 to 2020 using principal component analysis, residual analysis, Theil-Sen Median analysis, and partial correlation analysis. The results showed that on a temporal scale, the vegetation NPP showed a fluctuating upward trend, with a rate of 3.54 g·(m2·a)-1in southwest China from 2000 to 2021. Meanwhile, under the influence of climate change and human activities, NPP of farmland, grassland, and forests all showed an upward trend, but the magnitude of the increasing trends of farmland NPP was the most significant. On the spatial scale, the areas with an upward trend in vegetation NPP accounted for 89.06% in southwest China, and the areas with significant and extremely significant increases were mainly distributed in southern Guangxi, eastern Sichuan, western Chongqing, and the junction areas of Yunnan and Guizhou. Climate change and human activities had dual effects on vegetation growth in southwest China, and the proportions of the areas with upward trends in farmland NPP were higher than that of grassland and forests both under the influences of climate change and human activities. The correlations between vegetation NPP and climate factors showed obvious regional differences in southwest China. On the regional scale, the areas with a positive correlation between vegetation NPP and temperature, precipitation, and sunshine duration were greater than that of the areas with a negative correlation. However, an opposite relationship could be found between vegetation NPP and biological aridity/humidity index. Among them, the areas with a positive correlation between vegetation NPP and temperature were greater than that with other climate factors. In terms of different vegetation ecosystems, temperature, precipitation, and sunshine duration had a stronger role in promoting NPP variation in the grassland ecosystem than in farmland and forest ecosystems. The transformation of other land use types to forest land had contributed to vegetation improvement in southwest China.
Assuntos
Ecossistema , Modelos Teóricos , Humanos , China , Florestas , Temperatura , Mudança ClimáticaRESUMO
This study explored the temporal and spatial variation in PM2.5 concentration and its relationship with the vegetation landscape pattern in three typical economic zones in China, which is of great significance for regional PM2.5pollution control and atmospheric environmental protection. In this study, the pixel binary model, Getis-Ord Gi* analysis, Theil-Sen Median analysis, Mann-Kendall significance test, Pearson correlation analysis, and multiple correlation analysis were used to explore the spatial cluster and spatio-temporal variation in PM2.5 and its correlation with the vegetation landscape index in the three economic zones of China on the basis of PM2.5 concentration data and MODIS NDVI data set. The results showed that PM2.5 in the Bohai Economic Rim was mainly dominated by the expansion of hot spots and the reduction in cold spots from 2000 to 2020. The proportion of cold spots and hot spots in the Yangtze River Delta showed insignificant changes. Both cold and hot spots in the Pearl River Delta had expanded. PM2.5 showed a downward trend in the three major economic zones from 2000 to 2020, and the magnitudes of increasing rates were higher in the Pearl River Delta, followed by those in the Yangtze River Delta and Bohai Economic Rim. From 2000 to 2020, PM2.5 exhibited a downward trend in the context of all vegetation coverage grades, and PM2.5 had most significantly improved within extremely low vegetation coverage in the three economic zones. On the landscape scale, PM2.5 values were mostly correlated with aggregation index in the Bohai Economic Rim, with the largest patch index in the Yangtze River Delta and Shannon's diversity in the Pearl River Delta, respectively. Under the context of different vegetation coverage levels, PM2.5showed the highest correlation with aggregation index in the Bohai Economic Rim, landscape shape index in the Yangtze River Delta, and percent of landscape in the Pearl River Delta, respectively. PM2.5 showed significant differences with vegetation landscape indices in the three economic zones. The combined effect of multiple vegetation landscape pattern indices on PM2.5 was stronger than that of the single vegetation landscape pattern index. The above results indicated that the spatial cluster of PM2.5 in the three major economic zones had changed, and PM2.5 showed a decreasing trend in the three economic zones during the study period. The relationship between PM2.5 and vegetation landscape indices exhibited obvious spatial heterogeneity in the three economic zones.
RESUMO
Studies on the dynamic variation in vegetation cover and detecting its influencing factors are highly valuable for monitoring regional ecological environment quality and evaluating forestry restoration project effects. In this study, on the basis of the MODIS normalized difference vegetation index (NDVI), in situ climate data, digital elevation model, population density, nighttime lights using Theil-Sen Median analysis, Mann-Kendall significance test, stability analysis, and geographical detector model, the spatiotemporal variation and stability of vegetation cover in the context of multi-spatiotemporal scales were analyzed, and the dominant influencing factors that affect the spatial differentiation of vegetation cover were further detected. The results showed that the vegetation cover showed a fluctuant increasing trend, and the changing trend exhibited obvious spatial heterogeneity with the increasing rate being higher in the middle and lower in the east and west portion of the Yangtze River basin from 2000 to 2020. At the sub-basin scale, except for that in the Taihu Lake basin, the vegetation cover in all sub-basin units exhibited an increasing trend during the study period. The areas with an increasing trend accounted for 84.09% of the study area, in which the areas with extremely significant increases and significant increases accounted for 53.67%, which were mainly distributed in the Wujiang River basin, Yibin-yichang, Jialing River basin, Han River basin, and Dongting Lake basin. The vegetation cover showed lower stability in the upper reaches of the Jinsha-shigu River basin and Taihu Lake basin and higher stability in other sub-basin units of the study area. Elevation was an important factor affecting the vegetation variation in all sub-basin areas. Climatic factors presented the highest impact on vegetation variation in the upper reaches of the Jinsha-shigu River basin, and human activities exhibited the greatest impact on vegetation variation in the Wujiang River basin, lower reaches of Hukou basin, and Taihu Lake basin. The interaction of the two influencing factors on vegetation variation showed mutual and non-linear enhancement, and the interaction between elevation and wind speed presented the highest value, with an explanatory power of 68%. The ecological exploration results showed that human activities combined with topographic factors and climate factors, except for slope and relative humidity, significantly differed in the explanatory power of vegetation variation in the Yangtze River basin. These results can provide a basis for formulating comprehensive vegetation resource management in the Yangtze River basin that takes into account regional climate, topography, and human activities.
Assuntos
Lagos , Plantas , Rios , Clima , Plantas/classificação , VentoRESUMO
The aim of the study was to evaluate the efficacy and preliminary outcomes of using a postauricular-groove approach without endoscopic assistance for the excision of parotid tumors. Patients who underwent parotidectomy using a postauricular-groove incision were selected for this study. For patients in which parotidectomy was difficult, namely, for tumors located in the deep lobe area, the parotid gland sternocleidomastoid space was fully utilized, and the tumor was resected from the posterior plane. A total of fifty-eight patients with parotid tumor were enrolled and divided into superior lobe group (n = 46) and deep lobe group (n = 12). The difference in operation time (94 vs 119 min) and postoperative drainage (20.18 vs 45.33 mL) was statistically significant between the tumors in the superficial and deep lobes. However, postoperative cosmetic VAS score was 10 (extremely satisfied) for all patients. The incidence of transient facial nerve paralysis was comparable (8.7% vs 16.7%), and all of them resolved spontaneously within 3 months. No recurrence of tumors was found in either group in the median follow-up interval of 26.45 months (range 22.2-35.3 months), which was comparable to the result using the conventional "S" approach. After making full use of the parotid gland sternocleidomastoid space, the postauricular-groove approach demonstrated satisfactory facial nerve protection, as well as easy maneuverability without the risk of surgical complications for tumors located in the deep lobe area. Importantly, the postauricular-groove approach showed excellent cosmetic outcomes for all patients and should be considered an alternative approach for parotidectomy of selected cases.
Assuntos
Paralisia Facial , Neoplasias Parotídeas , Paralisia Facial/etiologia , Estudos de Viabilidade , Humanos , Glândula Parótida/cirurgia , Neoplasias Parotídeas/cirurgia , Complicações Pós-OperatóriasRESUMO
Studying vegetation cover variation and its responding mechanism to climate change and human activities is of great significance for regional ecological protection and vegetation restoration. In this study, on the basis of MODIS NDVI, in situ climate data, and land use type data using Theil-Sen Median analysis, the Mann-Kendall significance test, residual analysis, partial correlation analysis, and multi-correlation analysis, the spatial and temporal variation in vegetation cover and its response to climate change and the land use/land cover change in each geomorphological unit in southwest China were analyzed. The vegetation cover showed a fluctuant increasing trend, and the changing trend exhibited obvious spatial heterogeneity, with the increasing rate being higher in the southeast and lower in the northwest of southwest China from 2000 to 2020. The vegetation variation was dominated by positive effects of the climate change and human activities in southwest China, and the positive effects were stronger in Guangxi Hill than those in other geomorphological units. Furthermore, from 2000 to 2020 the vegetation cover was positively associated with precipitation and temperature and negatively correlated with relative humidity and sunshine duration in southwest China. Temperature was considered to be the dominate climate factor controlling the vegetation variation in the study area. Urban expansion had decreased the region vegetation cover, but the overall vegetation cover had increased in southwest China due to the suitable regional climate conditions and the implementation of ecological reforestation projection. These results can provide scientific references for ecological protection and economic sustainable development in southwest China.