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1.
Water Res ; 256: 121591, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38615606

RESUMO

Risk assessment and adaptation have become key focuses in the examination of urban flooding risk. In recent decades, global climate change has resulted in a high incidence of extreme weather events, notably flooding. This study introduces a spatial multi-indicator model developed for assessing flood risk at the urban agglomeration scale. A crucial addition to the model is the incorporation of an adaptive capacity within the IPCC risk framework. The model systematically considers various flood risk indicators related to the economic, social, and geographic environments of the central and southern Liaoning urban agglomeration (CSLN). It generates a spatial distribution map of integrated flood risk for multiple scenario combinations. Furthermore, the intricate relationship between different risk indicators and flood risk was analyzed using correlation analysis and the Light Gradient Boosting Machine model (Light GBM). The findings reveal notable variations in flood risk under different scenarios. The inclusion of vulnerability indicators increased flood risk by 33 %, while the subsequent inclusion of adaptive indicators decreased flood risk by 45 %. Dense populations and assets contribute to high flood risk, while adaptive capacity significantly mitigates urban flood risk. The framework adopted in this paper can be applied to other areas where urban agglomeration-scale flood risk assessment is needed, and can contribute to advancing scientific research on flood forecasting and mitigation.


Assuntos
Cidades , Inundações , Medição de Risco , Modelos Teóricos , Mudança Climática
2.
Dent J (Basel) ; 11(12)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38132410

RESUMO

BACKGROUND: To compare fatigue, comfort, and muscle work associated with the use of two periodontal curettes during scaling: one with a novel adaptive design, the other with a conventional non-adaptive design. METHODS: Twelve hygienists scaled a typodont using two Universal Barnhart 5/6 curettes: (1) a prototype featuring an adaptive silicone-covered handle (Curette A), and (2) a stainless-steel curette (Curette B). Surface Electromyography (sEMG) traced muscle work. Hand positions, fatigue, comfort, pinch, and grasp strength were recorded. Paired t-tests and a repeated measures ANOVA with covariates were tested for differences. The significance level was set at p < 0.05. RESULTS: Curette A performed significantly better in all categories. Pinch and grasp strength and fatigue were significantly reduced post-instrumentation for Curette B. Curette A required significantly less (i) total muscle work and (ii) work in individual muscles. Comfort, correct grasp, and blade adaptation were significantly better using Curette A. CONCLUSIONS: A curette featuring a novel adaptive handle design demonstrated significantly improved ergonomic performance. Additional clinical studies are needed to solidify our understanding of the potential short- and long-term benefits of the novel curette handle design. PRACTICAL IMPLICATIONS: A novel adaptive curette handle design that enables the clinician to adapt the instrument across the index finger may reduce musculoskeletal burden and fatigue, as well as improve comfort during periodontal instrumentation.

3.
Sci Total Environ ; 905: 167181, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37758134

RESUMO

Freshwater availability in coastal areas depends on the withdrawal from tidal rivers. It is severely threatened by saltwater intrusion, especially in the dry season. Freshwater availability is associated closely with natural factors and human activities. Limited research has investigated how freshwater availability is influenced by saltwater intrusion, streamflow, projects, etc., and how the water supply security downstream is affected by the abovementioned factors. To fill these gaps, this paper presents a new framework, i.e., water supply regulation by avoiding saltwater withdrawal (RASW). The framework is based on data on streamflow, tide, wind, the salinity of withdrawal stations, capacities of withdrawal projects and reservoirs, and water demand, which holistically develops relationships among saltwater intrusion, upstream streamflow, and water supply. The RASW contains three phases, i.e., estuary salinity-exceedance simulation, upstream streamflow distribution design, and local water supply security analysis. The proposed intellectual framework and methodology have been tested on the water supply for Zhuhai-Macao of the Guangdong-Hong Kong-Macao Great Bay Area, South China. Results demonstrated that the meta-Gaussian copula efficiently simulated the six-dimensional monthly streamflow distribution and was appropriate for streamflow distribution scenario design. Water supply security benefited greatly from the joint river-reservoir regulation mode. Nevertheless, the water supply security was threatened in the extreme scenarios when the extremely low streamflow distribution happened in the late period or lasted for an extended period. The proposed framework facilitates integrated decision-making for water supply security in coastal areas. Utilizing the streamflow distribution as a management tool and controlling them to avoid extremely low streamflow and adjust their occurrence time can alleviate water supply pressure. Moreover, the capacities of local regulating facilities should be designed with full consideration.

4.
Sci Total Environ ; 902: 166361, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595901

RESUMO

In the context of current global climate change, accurate drought prediction is crucial for water resources management and agricultural production. Although traditional drought forecasting methods largely rely on historical climatic data, these methods cannot fully consider the long-term effects of factors, such as climate change, and the evaluation of prediction results is limited. Therefore, this study proposed a drought prediction and evaluation framework based on Long Short-Term Memory (LSTM), integrating multi-source factors to significantly enhance the accuracy and reliability of drought prediction models. This framework applied two distinct forecasting schemes. The first scheme utilized ten diverse factors, including precipitation, evaporation, bare soil percentage area coverage, percentage crop cover, leaf area index, runoff, surface runoff, soil moisture, temperature, and total vegetated percentage cover, to predict future precipitation and evaporation, which was then used to calculate the Standardized Precipitation-Evaporation Index (SPEI) to evaluate drought characteristics. The second scheme directly used these ten factors and historical SPEI to predict future SPEI, further assessing future drought characteristics. By comparing the drought prediction results of the two schemes in terms of data statistics, drought characteristics, and spatial patterns, it was found that the LSTM model significantly improved accuracy when handling high-dimensional complex data and predicting key factors such as precipitation, evaporation, temperature, and soil moisture. The first scheme was more accurate when predicting severe and extreme droughts, whereas the second scheme was more sensitive to predicting moderate and mild droughts and exhibited higher stability and regularity in predicting the spatial variability of drought. In summary, LSTM has made significant improvements in the accuracy, stability, and reliability of drought prediction, providing stronger support for practical applications, such as agriculture and water resources management, and offering a new research tool for further climate change research.

5.
Sci Total Environ ; 874: 162624, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36878300

RESUMO

As a major component of the cryosphere, permafrost plays important roles in the climate system and land surface processes of the Earth. Owing to the rapidly warming climate, permafrost over the globe has degraded in recent decades. However, quantifying the distribution and temporal changes in permafrost is challenging. In this study, we modified the widely used surface frost number model by considering the spatial distribution of soil hydrothermal properties and then revisited the spatiotemporal patterns of permafrost distribution and its changes during the past decades (1961-2017) in China. We found that the modified surface frost number model performs well in simulating permafrost extent in China, with the overall accuracy and kappa coefficients being 0.92 and 0.78 in the calibration (1980s) and 0.94 and 0.77 in the validation period (2000s). Based on the modified model, we also found that permafrost extent in China demonstrated a significant decreasing trend over the past decades, especially on the Qinghai-Tibet Plateau (QTP), with a trend of -1.15 × 104 km2/yr (P < 0.01). Moreover, there is a significant relationship between ground surface temperature and permafrost distribution area, with the R2 being 0.41, 0.42, and 0.77 in NE and NW China and on the QTP. The sensitivity of permafrost extent to ground surface temperature in NE China, NW China, and the QTP, respectively, was -8.56 × 104, -1.97 × 104, and -34.60 × 104 km2/°C, respectively. Permafrost degradation has accelerated since the late 1980s, possibly due to increased climate warming. This study is of great significance for improving permafrost distribution simulation at large spatial scales (trans-regional) and for offering vital information for adapting to climate change in cold regions.

6.
Curr Oncol ; 30(1): 1046-1053, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36661729

RESUMO

Late detection and specialist referral result in poor oral cancer outcomes globally. High-risk LRMU populations usually do not have access to oral medicine specialists, a specialty of dentistry, whose expertise includes the identification, treatment, and management of oral cancers. To overcome this access barrier, there is an urgent need for novel, low-cost tele-health approaches to expand specialist access to low-resource, remote and underserved individuals. The goal of this study was to compare the diagnostic accuracy of remote versus in-person specialist visits using a novel, low-cost telehealth platform consisting of a smartphone-based, remote intraoral camera and custom software application. A total of 189 subjects with suspicious oral lesions requiring biopsy (per the standard of care) were recruited and consented. Each subject was examined, and risk factors were recorded twice: once by an on-site specialist, and again by an offsite specialist. A novel, low-cost, smartphone-based intraoral camera paired with a custom software application were utilized to perform synchronous remote video/still imaging and risk factor assessment by the off-site specialist. Biopsies were performed at a later date following specialist recommendations. The study's results indicated that on-site specialist diagnosis showed high sensitivity (94%) and moderate specificity (72%) when compared to histological diagnosis, which did not significantly differ from the accuracy of remote specialist telediagnosis (sensitivity: 95%; specificity: 84%). These preliminary findings suggest that remote specialist visits utilizing a novel, low-cost, smartphone-based telehealth tool may improve specialist access for low-resource, remote and underserved individuals with suspicious oral lesions.


Assuntos
Telemedicina , Populações Vulneráveis , Humanos , Telemedicina/métodos
7.
Cancer Immunol Immunother ; 72(3): 679-695, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36040519

RESUMO

BACKGROUND: Tumor heterogeneity plays essential roles in developing cancer therapies, including therapies for breast cancer (BC). In addition, it is also very important to understand the relationships between tumor microenvironments and the systematic immune environment. METHODS: Here, we performed single-cell, VDJ sequencing and spatial transcriptome analyses on tumor and adjacent normal tissue as well as axillar lymph nodes (LNs) and peripheral blood mononuclear cells (PBMCs) from 8 BC patients. RESULTS: We found that myeloid cells exhibited environment-dependent plasticity, where a group of macrophages with both M1 and M2 signatures possessed high tumor specificity spatially and was associated with worse patient survival. Cytotoxic T cells in tumor sites evolved in a separate path from those in the circulatory system. T cell receptor (TCR) repertoires in metastatic LNs showed significant higher consistency with TCRs in tumor than those in nonmetastatic LNs and PBMCs, suggesting the existence of common neo-antigens across metastatic LNs and primary tumor cites. In addition, the immune environment in metastatic LNs had transformed into a tumor-like status, where pro-inflammatory macrophages and exhausted T cells were upregulated, accompanied by a decrease in B cells and neutrophils. Finally, cell interactions showed that cancer-associated fibroblasts (CAFs) contributed most to shaping the immune-suppressive microenvironment, while CD8+ cells were the most signal-responsive cells. CONCLUSIONS: This study revealed the cell structures of both micro- and macroenvironments, revealed how different cells diverged in related contexts as well as their prognostic capacities, and displayed a landscape of cell interactions with spatial information.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Leucócitos Mononucleares , Linfonodos/patologia , Prognóstico , Perfilação da Expressão Gênica , Microambiente Tumoral
8.
J Periodontol ; 94(4): 509-518, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35980316

RESUMO

BACKGROUND: Gingivitis is a nonspecific inflammatory lesion in response to the accumulation of oral biofilm and is a necessary precursor to periodontitis. Enhanced oral hygiene practices are necessary to reverse gingivitis and a dentifrice that could provide significant clinical reductions in plaque accumulation and gingival inflammation would be desirable to treat gingivitis and potentially prevent progression to periodontitis. This clinical study aimed to investigate the effect of a novel stannous fluoride-containing dentifrice with 2.6% ethylenediamine tetra-acetic acid (EDTA) as an antitartar agent to reduce Plaque Index (PI) and Gingival Index over a 3-month study period. METHODS: This double-blind, randomized controlled clinical study evaluated plaque, gingival inflammation, and sulcular bleeding in patients using either a novel dental gel containing 0.454% stannous fluoride and 2.6% EDTA or a dentifrice with 0.24% sodium fluoride. Sixty subjects participated over a 3-month period. Co-primary endpoints were improvements in PI and Modified Gingival Index (mGI) from baseline values. No professional cleaning was performed during the study period. RESULTS: All subjects in the study demonstrated statistically significant improvements in all measures of oral hygiene over the 3-month study period. Subjects using the novel dental gel showed statistically significantly greater reductions in PI (ΔPI) [(-1.43 ± 0.34; -0.49 ± 0.13) (p < 0.00001)], mGI (ΔmGI) [(-1.11 ± 0.22; -0.16 ± 0.12) (p < 0.00001)], and modified sulcular bleeding index (ΔmSBI) [(-1.15 ± 0.18; -0.20 ± 0.07) (p < 0.00001)]. CONCLUSIONS: The novel dental gel demonstrated significant improvements in clinical parameters associated with gingivitis compared to a commercially available sodium fluoride dentifrice.


Assuntos
Placa Dentária , Dentifrícios , Gengivite , Humanos , Dentifrícios/uso terapêutico , Fluoreto de Sódio/uso terapêutico , Fluoretos de Estanho/uso terapêutico , Ácido Edético , Índice de Placa Dentária , Placa Dentária/terapia , Gengivite/tratamento farmacológico , Método Duplo-Cego , Inflamação/tratamento farmacológico
9.
J Environ Manage ; 320: 115813, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35963070

RESUMO

Drought, as a natural disaster, has widespread consequences and is notoriously difficult to manage. Critical to developing a drought management strategy is the identification and assessment of drought. To that end, this study developed a new composite index, called the standardized water cycle index (SWCI) based on the water cycle and water balance. The SWCI couplesd the key elements of the water cycle, including precipitation, evapotranspiration, leaf area index, surface runoff, and subsurface runoff, and requires the joint distribution of these elements which was determined using the D-vine copula. The Kendall transform was used to reduce the dimensionality of the five-element joint probability density function, which was then inversed to obtain the SWCI which was then evaluated with the data from the Pearl River basin obtained using the CMIP6. Results showed that the SWCI satisfactorily evaluated drought conditions, while reflecting the drought-mitigating effect of vegetation and subsurface runoff. The SWCI was also able to evaluate drought in areas with a high level of human activity.


Assuntos
Secas , Rios , China , Atividades Humanas , Humanos , Ciclo Hidrológico
10.
Sci Total Environ ; 847: 157620, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35901899

RESUMO

Aquaculture is one of the fastest growing fields of global food production industry in recent years. To maintain the ecological health of aquaculture water body and the sustainable development of aquaculture industry, the treatment of aquaculture tail water (ATW) is becoming an indispensable task. This paper discussed the demand of environmentally friendly and cost-effective technologies for ATW treatment and the potential of algal-bacterial symbiosis system (ABSS) in ATW treatment. The characteristics of ABSS based technology for ATW treatment were analyzed, such as energy consumption, greenhouse gas emission, environmental adaptability and the possibility of removal or recovery of carbon, nitrogen and phosphorus as resource simultaneously. Based on the principle of ABSS, this paper introduced the key environmental factors that should be paid attention to in the establishment of ABSS, and then summarized the species of algae, bacteria and the proportion of algae and bacteria commonly used in the establishment of ABSS. Finally, the reactor technologies and the relevant research gaps in the establishment of ABSS were reviewed and discussed.


Assuntos
Gases de Efeito Estufa , Purificação da Água , Aquicultura , Bactérias , Carbono , Nitrogênio/análise , Fósforo/análise , Simbiose , Águas Residuárias/microbiologia
11.
Magn Reson Imaging ; 88: 108-115, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35181470

RESUMO

BACKGROUND: The purpose of this study was to explore the prognostic value of imaging features and related models in nasopharyngeal carcinoma (NPC) patients that received neoadjuvant chemotherapy. MATERIALS AND METHODS: We systematically reviewed the data of 110 NPC patients who received radiotherapy and neoadjuvant chemotherapy. The patients were randomly divided into the training cohort (n = 88) and the verification cohort (n = 22). The imaging data collected in this study were screened via Pyramidics and used to construct prediction models based on histology and clinical nomographs. The models' accuracy was evaluated via calibration curves and the consistency index (C-index). In addition, we also explored the correlation between radiomics expression patterns, quantitative histological characteristics, and clinical data and then constructed a model to predict the prognosis of NPC. RESULTS: The models that integrated radiomics contours with all the clinical data were superior to those based on the clinical data alone (C-index 0.746 vs. C-index 0.814, respectively) and the calibration curves showed good consistency. The heat map showed that the radiomics expression pattern and selected histological characteristics were correlated with the clinical stage, T stage, and N stage (p < 0.05), and no radiomics feature was associated with lactate dehydrogenase expression, lymphocyte count, or mononuclear cell count. CONCLUSION: MRI-based radiomics can significantly improve the efficacy of traditional TNM staging and clinical data in predicting the progression-free survival (PFS) of patients with advanced NPC, which may provide an opportunity for precision medicine.


Assuntos
Neoplasias Nasofaríngeas , Terapia Neoadjuvante , Humanos , Imageamento por Ressonância Magnética/métodos , Carcinoma Nasofaríngeo/diagnóstico por imagem , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos
12.
J Contam Hydrol ; 242: 103860, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34333299

RESUMO

Soil moisture is an important indicator for monitoring land degradation and plays an important role in soil biogeochemistry. Mapping the spatial distribution of soil moisture provides fundamental information for soil management and agricultural production. In this study, 225 sampling points in the study area, Nanxiong basin, were investigated to map the spatial distribution of soil moisture in the typical ecological degradation red beds area. Four interpolation methods including inverse distance weighting (IDW), ordinary kriging (OK), radial basis function (RBF) and empirical bayesian kriging (EBF) were used to estimate the continuous soil moisture distribution. The results showed that the soil moisture of the study area ranged from 8.12% to 32.82% with an average of 18.42% and a median of 18.20%. The annual average temperature and soil bulk density had significantly negative correlations with soil moisture, of-0.53 and - 0.31, respectively. The regional soil moisture had a moderate variation with the variation coefficient of 21.66% and strong spatial dependence with the nugget-to-sill ratios of 32.23%. The IDW method obtained a more accurate estimation on the spatial variability of soil moisture in the Nanxiong basin. The spatial distribution of soil moisture in the study area was drawn by different interpolation methods. The results show that the red bed degradation in the eastern part of the Nanxiong basin is more severe than in other areas, in which the geomorphic characteristics of red bed desert have appeared with the lowest soil moisture in this study. In addition, the spatial heterogeneity of soil moisture is also pertinent to human disturbance and land use. The results of spatial soil moisture distribution are of great significance for monitoring land degradation and agricultural drought in the red bed area.


Assuntos
Monitoramento Ambiental , Solo , Teorema de Bayes , China , Humanos , Análise Espacial
13.
J Periodontol ; 92(9): 1286-1294, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33331040

RESUMO

BACKGROUND: Compliance to periodontal maintenance therapy (PMT) is essential for long-term periodontal health. Between PMT visits, patients must maintain good oral hygiene. A dentifrice with demonstrable clinical benefits for use between PMT visits would be highly desirable. The aim of this clinical study was to investigate the effect of a novel dental gel on probing depths (PD) and inflammation when used as a home care dentifrice in Stage I and II periodontitis patients. METHODS: This double-blind clinical study randomized 65 subjects with Stage I and II periodontitis to the novel dental gel containing 2.6% EDTA, and a commercially available anti-gingivitis dentifrice with 0.454% stannous fluoride. Primary endpoint was PD at 6 months for those sites with baseline PD ≥ 4 mm and secondary endpoints included whole mouth mean scores of modified gingival index (MGI), modified sulcus bleeding index (mSBI) and plaque index (PI). No SRP was performed at baseline. RESULTS: Subjects using the novel dentifrice showed significant PD reductions of 1.18 mm (from 4.27 mm at baseline to 3.09 mm at 6 months) compared to 0.93 mm (from 4.23 mm at baseline to 3.30 mm at 6 months) shown for those using the positive control dentifrice. Difference between treatments at 6 months was 0.21 mm with P-value = 0.0126. Significant improvements in MGI (P = 0.0000), mSBI (P = 0.0000), and PI (P = 0.0102) were also observed in 6 months. CONCLUSION: The novel dentifrice showed significant reductions in PD and gingival inflammation over 6 months solely as a home care dentifrice without baseline SRP in Stage I and II periodontitis maintenance patients.


Assuntos
Dentifrícios , Gengivite , Periodontite , Índice de Placa Dentária , Dentifrícios/uso terapêutico , Método Duplo-Cego , Humanos , Periodontite/tratamento farmacológico , Periodontite/prevenção & controle , Fluoretos de Estanho
14.
ERJ Open Res ; 6(2)2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32607373

RESUMO

The first case of #COVID19 in Foshan provides a reference for the treatment of severe #SARSCoV2 pneumonia https://bit.ly/3eD81qj.

15.
Water Res ; 175: 115670, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32171096

RESUMO

Numerous genetic markers have been developed to establish microbial source tracking (MST) assays in the last decade. However, the selection of suitable markers is challenging due to a lack of understanding of fundamental factors such as sensitivity, specificity, and concentration in target/nontarget hosts, especially in East Asia. In this study, a total of 506 faecal samples comprised of human and 12 nonhuman hosts were collected from 28 cities across China and tested for marker performance characteristics. We firstly tested 40 host-associated markers based on a binary (presence/absence) criterion. Here, 15 markers (7 human-associated, 4 pig-associated, 3 ruminant-associated, and 1 poultry-associated) showed potential applicability in our study area. The selected 15 markers were then tested using qualitative and quantitative methods to characterise their performance. Overall, Bacteroidales markers presented higher sensitivity and concentrations in target samples compared to other bacterial or viral markers, but their specificity was low. Among nontarget samples, pets accounted for 43.7% and 35.7% of cross-reactivity with human-associated and poultry-associated markers, respectively. Noncommon animals, including horse and donkey, contributed 61.3% of cross-reactivity with ruminant-associated markers. When considering the quantitative distribution of markers, their concentration in nontarget samples were 1-3 orders of magnitude lower than in target samples. Moreover, a novel classification method was proposed to classify the nontarget hosts into four groups spanning "no cross-reactivity", "weak cross-reactivity", "moderate cross-reactivity", and "strong cross-reactivity" animal hosts. There were 77.9% nontarget samples identified as no cross-reactivity and weak cross-reactivity hosts, suggesting that these nontarget hosts produce little interference for corresponding markers. Our findings elucidate the performance of host-associated markers around China in a qualitative and quantitative manner, and reveal the interference degree of cross-reactivity from nontarget animals to genetic markers, which will facilitate tracking of multiple faecal pollution sources and planning timely remedial strategies in China.


Assuntos
Bacteroidetes , Poluição Ambiental , Animais , China , Monitoramento Ambiental , Fezes , Marcadores Genéticos , Cavalos , Humanos , Suínos , Microbiologia da Água , Poluição da Água
16.
Sci Rep ; 9(1): 1961, 2019 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-30760736

RESUMO

This research examined the distribution features of red beds and 1,100 Danxia landform sites across China, while probing the relationship between these spatial patterns and geological elements. This study is based on geological and tectonic maps of China. ArcGIS software was used to process the adjacent index, then perform a spatial analysis of Danxia landforms and red beds, and a coupling analysis of Danxia landforms and red beds with tectonics. Based on a point pattern analysis of Danxia landforms, the adjacent index is 0.31, and the coefficient of variation verified by Thiessen polygon reaches 449%. These figures reflect the clustered distribution pattern of the Danxia landforms. Across the country, Danxia landforms are concentrated into three areas, namely, the Southeast China region, the Sichuan Basin region and the Qilian-Liupan region. The exposure of red beds covers 9.16 × 105 km2, which accounts for 9.5% of the total land area of China. With this research background, the geological elements of tectonics and their effects on the distribution, number, and spatial pattern of Danxia landforms and red beds were analyzed.

17.
PeerJ ; 7: e6342, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30723625

RESUMO

Soil pH is the main factor affecting soil nutrient availability and chemical substances in soil. It is of great significance to study the spatial variability of soil pH for the management of soil nutrients and the prediction of soil pollution. In order to explore the causes of spatial variability in soil pH in red-bed areas, the Nanxiong Basin in south China was selected as an example, and soil pH was measured in the topsoil by nested sampling (0-20 cm depth). The spatial variability characteristics of soil pH were analyzed by geostatistics and classical statistical methods, and the main factors influencing spatial variability in soil pH are discussed. The coefficient of variation in the red-bed areas of Nanxiong Basin was 17.18%, indicating moderate variability. Geostatistical analysis showed that the spherical model is the optimal theoretical model for explaining variability in soil pH, which is influenced by both structural and random factors. Analysis of the spatial distribution and pattern showed that soil pH is relatively high in the northeast and southwest, and is lower in the northwest. These results indicate that land use patterns and topographic factors are the main and secondary influencing factors, respectively.

18.
J Dent Oral Sci ; 1(3)2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31893264

RESUMO

OBJECTIVE: Overall aim of this prospective, randomized, positive controlled, double-blind in vivo study was to identify the effects of a test dental gel containing 2.6% edathamil with an added carrier and permeability enhancer vs. a positive control dentifrice on periodontal health measures in patients with Stage II and III periodontitis. METHODS: In this prospective double-blinded, randomized study, 33 subjects were randomly assigned in a 1:1 ratio to brushing their teeth with either the test gel (LivFresh®, Livionex Dental Gel, Los Gatos, CA 95030) or the positive control toothpaste (Crest ProHealth®, P&G, Cincinnati, OH 45202).Full-mouth gingival index, modified sulcus bleeding index, and periodontal pocket probing depths were recorded for all teeth at baseline, and on days 90 and 180.Subjects brushed with the study material twice a day. RESULTS: The test dental gel reduced gingival inflammation and bleeding, as well as periodontal pocket probing depths significantly more than a control dentifrice. CONCLUSIONS: In this pilot study in subjects with Stage II and III periodontitis, a test dental gel was found to improve gingival inflammation and bleeding, as well as periodontal pocket depths significantly better than a control dentifrice.

19.
Hum Immunol ; 80(3): 195-203, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576702

RESUMO

T cell receptors (TCRs) are a class of T cell surface molecules that recognize the antigen-derived peptides presented by the major histocompatibility complex (MHC) and are able to trigger a series of immune responses. TCRs are important members of the adaptive immune system that arose in the jawed fish 500 million years ago. T cell receptor beta variable (TRBV) genes have been widely used to characterize TCR repertoires. Studying the evolution of TRBV may help us to better understand the adaptive immune system. To investigate TRBV evolution and its impacts on the usages of TRBV genes in human populations, we compared the TRBV genes and their homologous sequences among humans, mouse, rhesus and chimpanzee, analyzed the single-nucleotide polymorphisms (SNPs) located at TRBV loci, and sequenced TCR repertoires in the peripheral blood of 97 healthy donors. We found that functional TRBVs are more evolutionarily conserved but possess more SNPs in human populations than do nonfunctional (pseudo) TRBVs. Based on the conservation levels in the four species, we classified the functional TRBVs into 2 groups: old (conserved between mouse and humans) and new (conserved only in primates). The new TRBVs evolve faster and possess more SNPs than the old TRBVs. The variations in TRBV genes frequencies in the peripheral blood of healthy donors are negatively correlated with SNP density. These observations suggest that TRBV usages may be influenced by TCR-MHC co-evolution.


Assuntos
Evolução Molecular , Variação Genética , Genética Populacional , Polimorfismo de Nucleotídeo Único , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Animais , Voluntários Saudáveis , Humanos , Camundongos , Filogenia , Primatas , Linfócitos T/metabolismo
20.
Front Immunol ; 9: 2729, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30524447

RESUMO

There is increasing evidence that deep sequencing-based T cell repertoire can sever as a biomarker of immune response in cancer patients; however, the characteristics of T cell repertoire including diversity and similarity, as well as its prognostic significance in patients with cervical cancer (CC) remain unknown. In this study, we applied a high throughput T cell receptor (TCR) sequencing method to characterize the T cell repertoires of peripheral blood samples from 25 CC patients, 30 cervical intraepithelial neoplasia (CIN) patients and 20 healthy women for understanding the immune alterations during the cervix carcinogenesis. In addition, we also explored the signatures of TCR repertoires in the cervical tumor tissues and paired sentinel lymph nodes from 16 CC patients and their potential value in predicting the prognosis of patients. Our results revealed that the diversity of circulating TCR repertoire gradually decreased during the cervix carcinogenesis and progression, but the circulating TCR repertoires in CC patients were more similar to CIN patients than healthy women. Interestingly, several clonotypes uniquely detected in CC patients tended to share similar CDR3 motifs, which differed from those observed in CIN patients. In addition, the TCR repertoire diversity in sentinel lymphatic nodes from CC patients was higher than in tumor tissues. More importantly, less clonotypes in TCR repertoire of sentinel lymphatic node was associated with the poor prognosis of the patients. Overall, our findings suggested that TCR repertoire might be a potential indicator of immune monitoring and a biomarker for predicting the prognosis of CC patients. Although functional studies of T cell populations are clearly required, this study have expanded our understanding of T cell immunity during the development of CC and provided an experimental basis for further studies on its pathogenesis and immunotherapy.


Assuntos
Biomarcadores Tumorais , Regiões Determinantes de Complementaridade , Receptores de Antígenos de Linfócitos T , Neoplasias do Colo do Útero , Adulto , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Regiões Determinantes de Complementaridade/sangue , Regiões Determinantes de Complementaridade/genética , Regiões Determinantes de Complementaridade/imunologia , Feminino , Humanos , Linfonodos/imunologia , Linfonodos/metabolismo , Linfonodos/patologia , Pessoa de Meia-Idade , Prognóstico , Receptores de Antígenos de Linfócitos T/sangue , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Neoplasias do Colo do Útero/sangue , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/imunologia
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