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1.
PLoS One ; 18(6): e0286800, 2023.
Article in English | MEDLINE | ID: mdl-37289676

ABSTRACT

Understanding the spatial distribution of urban forest ecosystem services is essential for urban planners and managers to effectively manage cities and is an essential part of sustainable urban development. Mapping the spatial distribution of urban forest ecosystem services and improving the accuracy of its assessment scale will undoubtedly provide a more accurate reference basis for later management. In this study, we used the i-Tree Eco model and kriging interpolation to quantify and map urban forest ecosystem services and their spatial distribution in Zhengzhou, a city along the lower reaches of the Yellow River in China; analyzed the mapping errors and applicable conditions; and further explored the spatial differences using geographic probes. The i-Tree Eco model estimation results showed that the total carbon storage in the urban forest of Zhengzhou city was 75.7 tons, the annual carbon sequestration was 14.66 tons, the trees and shrubs in the urban area of Zhengzhou city could effectively avoid a total of 307.86 m3 of surface runoff per year, and trees and shrubs removed 411.8 kg/year of air pollution (O3, CO, NO2, PM2.5, PM10, and SO2). The spatial distribution of all urban forest ecosystem services showed significant heterogeneity, but the spatial evaluation precision of different factors varied. GDP and population data showed a negative correlation with ecosystem services, and ecosystem services were abundant in watershed and woodland areas. This study differs from traditional assessments based on regional data due to its improved spatial evaluation accuracy, and the results, discussion, and analysis not only help Zhengzhou's own urban development, but also provide a basis for the future construction and management of other cities, the Central Plains urban agglomeration, and the surrounding larger regions. This will contribute to the enhancement of ecosystem services and thus improve the ecological conditions of the region. This will also have a positive effect on the health of urban residents.


Subject(s)
Ecosystem , Forests , Cities , Trees , Spatial Analysis , China , Conservation of Natural Resources
2.
PLoS One ; 17(8): e0272626, 2022.
Article in English | MEDLINE | ID: mdl-35947622

ABSTRACT

Urban heat islands are major factors hindering the quality of present-day urban habitats. The ongoing acceleration of the worldwide urbanization process is leading to an exacerbation of the urban heat island effect; however, urban forestry can mitigate it. For a sustainable urban development, it is particularly important to evaluate the dual effect of both factors on the urban heat island phenomenon. In this study, we focused on Zhengzhou City (China), at the center of the Central Plains Forest City Cluster. The spatial and temporal evolutions of the local urban heat island and vegetation coverage were measured from Landsat 5 and Landsat 8 remote sensing images taken between 2006-2020 and the effects of urban construction and urban forestry on the urban heat island effect were evaluated. The results showed that, in the past 15 years, the high-temperature zone in the urban area of Zhengzhou City has gradually spread from its center to surrounding areas. Within the same period, the whole urban heat island has deteriorated and gradually improved: its area increased by 138.72 km2 between 2006-2014 and decreased by 135.66 km2 between 2014-2020. Notably, the development of vegetation coverage occurred consistently with the improvement of the heat island. A quantitative analysis of the relationship between urban construction, the urban forest, and the urban heat island has shown that factors like population density (representing urban construction), urban planning, and vegetation cover (representing the urban forest) all have an impact on the urban heat island. Based on the dynamic changes of the urban heat island in the urban area of Zhengzhou City between 2006-2020, we conclude that urban forest construction strategies are beginning to bear fruit. Overall, the findings of this study provide a theoretical basis for future urban construction and urban forest construction plans; moreover, they can support landscape pattern optimization and urban heat island mitigation.


Subject(s)
Hot Temperature , Urbanization , Cities , Environmental Monitoring/methods , Forestry
4.
Open Med (Wars) ; 17(1): 22-33, 2022.
Article in English | MEDLINE | ID: mdl-34950770

ABSTRACT

Papillary thyroid carcinoma (PTC) is the most frequent histological type of differentiated thyroid carcinoma. Long noncoding RNAs (lncRNAs) have been widely reported to play a key role in human malignancies, and PTC is included. This study aimed to find out the functions and mechanism of lncRNA LINC00475 in PTC. LINC00475 was upregulated in PTC cells and was mainly located in the cytoplasm according to reverse-transcription polymerase chain reaction analyses and subcellular fractionation assays. As shown by cell counting kit-8 assays, ethynyl deoxyuridine incorporation assays, wound healing assays, and transwell assays, LINC00475 knockdown suppressed cell viability, proliferation, migration, and invasion. Mechanistically, LINC00475 upregulated the expression of messenger RNA zinc finger CCHC-type containing 12 (ZCCHC12) by binding to miR-376c-3p. ZCCHC12 was a direct target gene of miR-376c-3p in PTC cells. The relationship between miR-376c-3p and LINC00475 (or ZCCHC12) in PTC cells was probed by luciferase reporter assays, RNA pulldown assays, and RNA immunoprecipitation assays. In addition, both mRNA and protein levels of ZCCHC12 were downregulated due to miR-376c-3p overexpression or LINC00475 silencing. ZCCHC12 overexpression partially reversed the suppressive effect of LINC00475 knockdown on malignant behaviors of PTC cells. In conclusion, LINC00475 promotes PTC cell proliferation, migration, and invasion by upregulating ZCCHC12 via the interaction with miR-376c-3p.

5.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(5): 451-455, 2021 May.
Article in Chinese | MEDLINE | ID: mdl-34020732

ABSTRACT

OBJECTIVE: To study the clinical features of children with influenza A virus infection and neurological symptoms. METHODS: A retrospective analysis was performed for the clinical data of children with laboratory-confirmed influenza A and neurological symptoms who were treated in Xi'an Children's Hospital Affiliated to Xi'an Jiaotong University from January to December, 2019. RESULTS: A total of 895 children were diagnosed with influenza A, among whom 291 had neurological symptoms. Boys had a significantly higher incidence rate of influenza A than girls (P < 0.05), and the children aged 1-3 years had a significantly higher incidence rate than the other age groups (P < 0.05). Common neurological symptoms included seizures (97.3%), vomiting (24.1%), and headache (7.2%). Febrile seizures were the most common type of seizures, accounting for 88%. There was no significant difference in the time from disease onset to seizures and frequency seizures between the children with a history of febrile seizures and those without such history (P > 0.05). Of all the children, 3 were diagnosed with acute necrotizing encephalopathy (ANE), all of whom were girls and suffered seizures; the time from the first seizures to the occurrence of disturbance of consciousness was 0-7 hours, and 2 girls died within 2 days after disease onset. All children, except 2 who died of ANE and 1 with neurological sequelae, were cured. CONCLUSIONS: There is a high incidence rate of neurological symptoms in children with influenza A, and seizures are the most common symptom. Most of the patients with neurological symptoms tend to have a good prognosis, but those with ANE may have a poor prognosis.


Subject(s)
Brain Diseases , Influenza A virus , Influenza, Human , Child , Child, Preschool , Female , Humans , Infant , Influenza, Human/complications , Influenza, Human/epidemiology , Male , Retrospective Studies , Seizures
6.
PeerJ ; 9: e11346, 2021.
Article in English | MEDLINE | ID: mdl-33987020

ABSTRACT

BACKGROUNDS: Nonalcoholic fatty liver disease (NAFLD) has multiple causes, is triggered by individual genetic susceptibility, environmental factors, and metabolic disturbances, and may be triggered by acquired metabolic stress. The metabolic profiles of NAFLD show significant ethnic differences, and the metabolic characteristics of NAFLD in Chinese individuals are unclear. Our study aimed to identify the metabolites and pathways associated with NAFLD in a Chinese cohort. METHODS: One hundred participants, including 50 NAFLD patients and 50 healthy controls, were enrolled in this retrospective observational study at Jinling Hospital in Nanjing; serum samples were collected from the patients and healthy subjects. The metabolome was determined in all samples by liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry (LC-Q/TOF-MS). Univariate and multivariate statistical analyses were used to compare the metabolic profiles between the two groups. RESULTS: The comparison indicated that the levels of 89 metabolites were different between the two groups. The glycerophospholipid family of metabolites was the most abundant family of metabolites that demonstrated significant differences. L-acetylcarnitine, L-homocitrulline, and glutamic acid were the top three metabolites ranked by VIP score and had favorable effective functions for diagnosis. Moreover, pathway enrichment analysis suggested 14 potentially different metabolic pathways between NAFLD patients and healthy controls based on their impact value. Biological modules involved in the lipid and carbohydrate metabolism had the highest relevance to the conditions of NAFLD. Glycerophospholipid metabolism had the strongest associations with the conditions of NAFLD. CONCLUSIONS: Our data suggest that the serum metabolic profiles of NAFLD patients and healthy controls are different. L-Homocitrulline was remarkably increased in NAFLD patients.

7.
Clin Exp Hepatol ; 7(4): 437-444, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35402723

ABSTRACT

Aim of the study: To explore the correlation of the liver-to-spleen (L/S) ratio on computed tomography (CT) with colorectal polyps. Material and methods: Consecutive participants from Jinling Hospital Affiliated to Nanjing University who underwent routine biochemical tests, colonoscopies, and CT between January 2018 and December 2019 were selected. The L/S ratio on CT was used to measure the liver fat content. Colonoscopy findings were applied to create the polyp-free group and colorectal polyp group. All included subjects were also classified in the non-alcoholic fatty liver disease (NAFLD) group or the non-NAFLD group according to the CT (L/S) ratio to identify risk factors for colorectal polyps. All data were analysed with SPSS 25 software. Results: Among 481 participants, 27.8% (79/284) of the patients were diagnosed with NAFLD in the colorectal group, which was higher than the corresponding proportion of the polyp-free group [9.1% (18/197)]. In NAFLD patients, most adenomatous polyps were found in the transverse colon, and hyperplastic polyps were largely located in the rectum. Linear regression suggested that the CT (L/S) ratio correlated with the number of colorectal polyps and with the number of adenomatous polyps. After adjusting for confounding factors, multivariate analysis indicated that NAFLD was an independent risk factor for adenomatous polyps and hyperplastic polyps. Conclusions: A lower CT (L/S) ratio (higher liver fat content) was significantly correlated with a higher risk of colorectal polyps. This finding suggested that NAFLD patients with a reduced CT (L/S) ratio need to undergo colonoscopy examinations to detect high-risk colorectal polyps in a timely manner.

8.
Stat Methods Med Res ; 29(2): 421-436, 2020 02.
Article in English | MEDLINE | ID: mdl-30868935

ABSTRACT

The 5-parameter logistic (5PL) model is frequently used to model and analyze responses from bioassays and immunoassays which can be skewed. Various types of optimal experimental designs for 2, 3 and 4-parameter logistic models have been reported but not for the more complicated 5PL model. We construct different types of optimal designs for studying various features of the 5PL model and show that commonly used designs in bioassays and immunoassays are generally inefficient for statistical inference. To facilitate use of such designs in practice, we create a user-friendly software package to generate various tailor-made optimal designs for the 5PL model and evaluate robustness properties of a design under a variation of criteria, model forms and misspecification in the nominal values of the model parameters.


Subject(s)
Biological Assay/statistics & numerical data , Data Interpretation, Statistical , Immunoassay/statistics & numerical data , Algorithms , Bias , Logistic Models
9.
Oncol Res ; 26(5): 713-723, 2018 Jun 11.
Article in English | MEDLINE | ID: mdl-28800788

ABSTRACT

MicroRNAs (miRNAs) are small noncoding RNAs that are involved in human carcinogenesis and progression. miR-204 has been reported to be a tumor suppressor in several cancer types. However, the function and underlying molecular mechanism of miR-204 in cervical cancer (CC) are still unclear. In the present study, the expression level of miR-204 was measured using the qRT-PCR method in 30 paired CC clinical samples and in 6 CC cell lines. We found that the expression of miR-204 was significantly downregulated in CC tissues and cell lines compared to normal cervical tissues and cell line. miR-204 was overexpressed by transfection with the miR-204 mimic in HeLa and C33A cell lines in the following experiments. The results showed that overexpression of miR-204 dramatically suppressed cell proliferation, migration, and invasion, caused cell cycle arrest at the G0/G1 phase, promoted cell apoptosis in vitro, and inhibited tumor growth in vivo. Western blot results indicated that overexpressing miR-204 decreased the expressions of CDK2, cyclin E, MMP2, MMP9, Bcl2, whereas it enhanced Bax expression and suppressed the activation of the PI3K/AKT signaling pathways in CC cells. Ephrin type B receptor 2 (EphB2) was identified as a direct target of miR-204 in CC cells according to bioinformatics analysis and luciferase reporter assay. Furthermore, knockdown of EphB2 mimicked the inhibitory effect of miR-204 on the proliferation, invasion, and migration of CC cells. These findings suggested that miR-204 might serve as a tumor suppressor in the development of CC by directly targeting EphB2.


Subject(s)
Gene Expression Regulation, Neoplastic/genetics , MicroRNAs/genetics , Neoplasm Invasiveness/genetics , Receptor, EphB2/biosynthesis , Uterine Cervical Neoplasms/pathology , Animals , Cell Line, Tumor , Cell Proliferation/genetics , Female , Heterografts , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Invasiveness/pathology , Receptor, EphB2/genetics , Uterine Cervical Neoplasms/genetics
10.
Accid Anal Prev ; 83: 197-202, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26310800

ABSTRACT

Truck-related crashes contribute to a significant percentage of vehicle crashes in the United States, which often result in injuries and fatalities. The amount of truck miles traveled has increased dramatically with the growing rate of freight movement. Regarding truck crashes in the highway work zones, many studies indicated that there was a significant increase in crash severity when a truck crash occurred in work zones. To mitigate the risk of truck crashes in work zones, a portable changeable message sign (PCMS) was frequently utilized in addition to standard temporary traffic control signs and devices required by the Manual on Uniform Traffic Control Devices. To justify the use of a PCMS in work zones, there is a need to study the effective location of a PCMS deployed in a work zone by measuring the changes of truck and passenger car speed profiles. The difference of speed changes between trucks and passenger cars was considered as one of the major reasons which caused truck-related crashes in work zones. Therefore, reducing the difference of speed changes between trucks and passenger cars could potentially improve safety in work zones. The outcomes of this study will provide required knowledge for traffic engineers to effectively utilize the PCMS in work zones with the purpose of reducing truck-related crashes. In addition, the success of this study will provide a roadmap to investigate the effective deployment of other temporary traffic control devices on mitigating the risk of truck-related crashes in work zones.


Subject(s)
Accidents, Traffic/prevention & control , Automobile Driving/psychology , Communication , Motor Vehicles , Environment Design , Humans , Risk , Safety , United States
11.
J Opt Soc Am A Opt Image Sci Vis ; 29(4): 426-30, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22472817

ABSTRACT

Luneburg lenses are able to form perfect focus that is free of aberration. Because of the varying refractive index throughout the lens, incoming electromagnetic waves can travel in a curved path and be guided to focus at the back of the lens. The implementation of Luneburg lenses is often difficult due to the challenges in creating a medium with varying refractive index using normal materials. This problem can be overcome with the use of gradient index metamaterials. We report a two dimensional Luneburg lens made of gradient index metamaterials. It consists of 17 concentric shells with etched patterns on a printed circuit board working in microwave X band frequency. The broad properties of the Luneburg lens are then discussed.

12.
J Opt Soc Am A Opt Image Sci Vis ; 29(4): 473-5, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22472823

ABSTRACT

We present a device that is designed with varying permittivity ε(r) such that an electromagnetic wave in the K-band of the microwave regime entering it will bend inward towards the core. The core is made of silicon composites. We follow the distribution formula of the permittivity for the device derived by Narimanov and Kildishev using the optical-mechanical analogy. The diameter of the device is 14 cm, and it is constructed out of 21 rings of two different types of etched printed circuit boards, as well as dielectric powders as adding filling materials. The experimental wave intensity profile, based on parallel plate measurements for the cases where the incident plane wave is slightly displaced to the top of the center of the device and the case of on center incidence, are presented and discussed. In spite of some mismatch of the core and metamaterial structures of the device found, approximately 80% of the wave still manages to reach the core of the device and gets trapped and absorbed. Broadband properties of the device are also investigated.

13.
Cancer Inform ; 9: 1-9, 2010 Jan 21.
Article in English | MEDLINE | ID: mdl-20148167

ABSTRACT

BACKGROUND: Gene set enrichment analysis (GSEA) is an analytic approach which simultaneously reduces the dimensionality of microarray data and enables ready inference of the biological meaning of observed gene expression patterns. Here we invert the GSEA process to identify class-specific gene signatures. Because our approach uses the Kolmogorov-Smirnov approach both to define class specific signatures and to classify samples using those signatures, we have termed this methodology "Dual-KS" (DKS). RESULTS: The optimum gene signature identified by the DKS algorithm was smaller than other methods to which it was compared in 5 out of 10 datasets. The estimated error rate of DKS using the optimum gene signature was smaller than the estimated error rate of the random forest method in 4 out of the 10 datasets, and was equivalent in two additional datasets. DKS performance relative to other benchmarked algorithms was similar to its performance relative to random forests. CONCLUSIONS: DKS is an efficient analytic methodology that can identify highly parsimonious gene signatures useful for classification in the context of microarray studies. The algorithm is available as the dualKS package for R as part of the bioconductor project.

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