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1.
Materials (Basel) ; 17(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39124508

RESUMEN

Fiber concrete exhibits superior performance in various aspects compared to plain concrete and has been widely researched and applied worldwide. However, many industrially made fibers are expensive, and their cost has to be considered before use; thus, it would be economically valuable to find inexpensive fibers with excellent properties to make fiber concrete. Rural areas have many rich straw resources to be disposed of; at the same time, the rapid development of the automobile industry has introduced a large number of used tires containing steel wire with a very low reuse rate. These two low-cost materials can be processed to make fibers, making the study of mechanical properties regarding their incorporation into concrete practically significant for reducing the cost of fiber concrete. Based on this, a three-factor, three-level orthogonal test was conducted to investigate the effects of different dosages of corn straw fibers and scrap steel fibers, as well as the water-cement ratio, on the mechanical properties of concrete. The optimum level of each factor for blended straw-waste-steel-fiber concrete with different mechanical properties was obtained using the polar and ANOVA methods. It was found that the compressive strength, splitting tensile strength, flexural strength, and impact resistance of the specimens after fiber dosing were better than those of plain concrete specimens with the same water-cement ratio. The maximum improvement was 14.96% in cubic compressive strength, 42.90% in tensile strength, and 16.30% in flexural strength, while the maximum improvement in impact energy consumption at the final crack was 228.03%. Combined with SEM microanalysis, the two fibers formed a stronger whole with the C-S-H gel. When the specimen was subjected to load, the two fibers were able to withstand part of the load, thus enhancing the load-bearing capacity. Finally, the optimal mix ratio of blended straw-scrap-steel-fiber concrete was determined to be 0.8% corn straw fibers by volume, 0.6% scrap steel fibers by volume, and a 0.45 water-cement ratio by combining the weights of the levels of each factor under its four different mechanical properties through hierarchical analysis. This analysis of mechanical properties provides a reference for practical applications in future projects.

2.
Am Nat ; 204(2): 165-180, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39008838

RESUMEN

AbstractIn recent years, ecological research has become increasingly synthetic, relying on revolutionary changes in data availability and accessibility. In spite of their strengths, these approaches may cause us to overlook natural history knowledge that is not part of the digitized English-language scientific record. Here, we combine historic and modern documents to quantify species-specific nesting habitat associations of bumblebees (Bombus spp. Latreille, 1802 Apidae). We compiled nest location data from 316 documents, of which 81 were non-English and 93 were published before 1950. We tested whether nesting traits show phylogenetic signal, examined relationships between habitat associations at different scales, and compared methodologies used to locate nests. We found no clear phylogenetic signals, but we found that nesting habitat associations were somewhat generalizable within subgenera. Landcover associations were related to nesting substrate associations; for example, surface-nesting species also tended to be associated with grasslands. Methodology was associated with nest locations; community scientists were most likely and researchers using nest boxes were least likely to report nests in human-dominated environments. These patterns were not apparent in past syntheses based only on the modern digital record. Our findings highlight the tremendous value of historic accounts for quantifying species' traits and other basic biological knowledge needed to interpret global-scale patterns.


Asunto(s)
Ecosistema , Comportamiento de Nidificación , Especificidad de la Especie , Animales , Abejas/fisiología , Filogenia
3.
Environ Res ; 257: 119370, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38851375

RESUMEN

In order to improve the level of mine ecological environment management and restoration, and to improve and enhance the overall environmental quality of mines. This study takes coal mine as the perspective, and constructs evaluation indexes in two steps, i.e., social network analysis method and relevant policy documents are combined to construct evaluation indexes. The indicator system contains 5 first-level indicators and 23 s-level indicators, and the triangular fuzzy number hierarchical analysis method is introduced to determine the comprehensive weight of each evaluation indicator, which overcomes the inadequacy of the objective empowerment method or the subjective empowerment method of single empowerment. The grey correlation analysis theory is used to establish a grey correlation evaluation model of mine ecological environment, which is applied to the evaluation of ecological environmental protection level of four coal mines in a province of China, making full use of the information of each index for quantitative evaluation, and finally obtaining the evaluated value of ecological environmental protection level of each coal mine. It is demonstrated that the evaluation model can make scientific and effective evaluation of the level of ecological environmental protection in mines. The study concludes that coal mines should pay attention to improving the comprehensive utilization rate of coal gangue in the next mine ecological environment management and restoration, and at the same time, reduce the ton of coal power consumption, ton of coal water consumption, and Increase in vegetation cover. This study provides a useful evaluation method for ecological environment management in mining areas, which is helpful to improve the quality of ecological management in mining areas.


Asunto(s)
Minas de Carbón , Lógica Difusa , Conservación de los Recursos Naturales , China , Monitoreo del Ambiente/métodos , Minería , Modelos Teóricos
4.
Sci Rep ; 14(1): 14365, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38906924

RESUMEN

A large number of tectonically mixed rock belts and complex tectonic zones are distributed in the southwestern part of China. In these areas, high geostress and tectonic stresses have caused some underground rock layers to be crushed and broken, eventually forming crushed rock zones. Which may undergo creep deformation under long-term loads. The manuscript is based on a typical crushed rock in the southwestern China. Firstly, the factors affecting creep deformation were analysed, and the response law of each influencing factor to rock creep is demonstrated. Then, the theory of uncorroborated measures and hierarchical analysis were used to systematically correlate the factors influencing creep. Thereby, a creep level qualitative evaluating model of crushed rock is established. Finally, this model was used to qualitatively evaluate the creep level of the crushed rock in the study area. It is concluded that the creep level qualitative evaluating of this crushed rock is rated as Class II, which is characterised by a low creep level and small creep deformations (0-10 mm). The research results can provide a reference for the creep analysis of crushed rock and provide a basis for the safe construction of engineering slopes.

5.
Rev. int. med. cienc. act. fis. deporte ; 24(95): 1-23, mar.-2024. graf, tab
Artículo en Inglés | IBECS | ID: ibc-ADZ-313

RESUMEN

CBA is a sports event that allows fans to enjoy themselves and players to give full play, and traditional Chinese cultural values have a profound influence on it. This paper takes the 100 sets of historical rating data of the fourteen teams in CBA league as the basic basis, firstly, we simply deal with the 100 sets of historical rating data and use Excel function formula to find out the mean, extreme deviation and variance of each team, then we carry out SAS normal test, and we find that except for the very few data with large deviation, the historical rating data satisfy the normal distribution. Through the outlier algorithm to screen the values, compare the confidence intervals as well as carry out hypothesis testing, to objectively and scientifically explore the probability of each team winning the championship in the CBA league. Compare the probability of winning the championship of these fourteen teams and predict the top four teams in the CBA league to ensure that the prediction results are as reasonable as possible. With the help of hierarchical analysis to qualitatively analyze the level of each team, and then through cluster analysis to compare these data, and combined with the trend of the development of the world's basketball movement, the use of multiple regression and SPSS to analyze the level of the team's factors, in-depth thinking about the league, a more reasonable to give a more scientific to improve the probability of the team's winning the championship, and to promote better development of the basketball movement. (AU)


Asunto(s)
Humanos , Intervalos de Confianza , Pruebas de Hipótesis , Predicción , Apoyo a la Investigación como Asunto , Baloncesto
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(1): 55-61, 2024 Feb.
Artículo en Chino | MEDLINE | ID: mdl-38433632

RESUMEN

Objective To build a whole-course nursing quality evaluation system for liver transplantation in children,so as to provide a basis for nursing quality evaluation and management. Methods With Donabedian's "structure-process-outcome" model as the theoretical framework,we employed literature analysis,Delphi method,and hierarchical analysis to determine the contents and weights of indexes in the whole-course nursing quality evaluation system for liver transplantation in children. Results The three rounds of survey based on questionnaires showed the questionnaire recovery rate of 100%,the expert authority coefficients of 0.95,0.96,and 0.98,and the Kendall's coefficients of concordance of 0.165,0.209,and 0.220,respectively(all P<0.001).The established nursing quality evaluation system included 3 first-level indexes,15 second-level indexes,and 67 third-level indexes. Conclusion The whole-course nursing quality evaluation system for liver transplantation in children that was built in this study can provide a basis for the evaluation of the nursing quality.


Asunto(s)
Trasplante de Hígado , Niño , Humanos
7.
BMC Public Health ; 24(1): 816, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38491478

RESUMEN

BACKGROUND: Cardiovascular diseases (CVDs) are the leading cause of death in Indonesia, accounting for 38% of the total mortality in 2019. Moreover, healthcare spending on CVDs has been at the top of the spending under the National Health Insurance (NHI) implementation. This study analyzed the association between the presence of CVDs with or without other chronic disease comorbidities and healthcare costs among adults (> 30 years old) and if the association differed between NHI members in the subsidized group (poorer) and non-subsidized households group (better-off) in Indonesia. METHODS: This retrospective cohort study analyzed the NHI database from 2016-2018 for individuals with chronic diseases (n = 271,065) ascertained based on ICD-10 codes. The outcome was measured as healthcare costs in USD value for 2018. We employed a three-level multilevel linear regression, with individuals at the first level, households at the second level, and districts at the third level. The outcome of healthcare costs was transformed with an inverse hyperbolic sine to account for observations with zero costs and skewed data. We conducted a cross-level interaction analysis to analyze if the association between individuals with different diagnosis groups and healthcare costs differed between those who lived in subsidized and non-subsidized households. RESULTS: The mean healthcare out- and inpatient costs were higher among patients diagnosed with CVDs and multimorbidity than patients with other diagnosis groups. The predicted mean outpatient costs for patients with CVDs and multimorbidity were more than double compared to those with CVDs but no comorbidity (USD 119.5 vs USD 49.1, respectively for non-subsidized households and USD 79.9 vs USD 36.7, respectively for subsidized households). The NHI household subsidy status modified relationship between group of diagnosis and healthcare costs which indicated a weaker effect in the subsidized household group (ß = -0.24, 95% CI -0.29, -0.19 for outpatient costs in patients with CVDs and multimorbidity). At the household level, higher out- and inpatient costs were associated with the number of household members with multimorbidity. At the district level, higher healthcare costs was associated with the availability of primary healthcare centres. CONCLUSIONS: CVDs and multimorbidity are associated with higher healthcare costs, and the association is stronger in non-subsidized NHI households. Households' subsidy status can be construed as indirect socioeconomic inequality that hampers access to healthcare facilities. Efforts to combat cardiovascular diseases (CVDs) and multimorbidity should consider their distinct impacts on subsidized households. The effort includes affirmative action on non-communicable disease (NCD) management programs that target subsidized households from the early stage of the disease.


Asunto(s)
Enfermedades Cardiovasculares , Multimorbilidad , Adulto , Humanos , Estudios Retrospectivos , Indonesia/epidemiología , Análisis Multinivel , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/terapia , Costos de la Atención en Salud
8.
Am J Clin Pathol ; 161(6): 535-542, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38365314

RESUMEN

OBJECTIVES: The human papillomavirus (HPV) screening assays from Atila Biosystems, including the new AmpFire (14 type) and ScreenFire RS (13 type), were subjected to a series of validation tests. METHODS: We used a set of samples from the Chinese Multi-Site Screening Trial (previously tested with cobas 4800 and the next-generation SeqHPV) to satisfy Meijer's criteria for clinical end-point validation. We selected 556 self-collected specimens composed of 273 high-risk HPV (hrHPV) positives and 283 hrHPV negatives on the cobas 4800 and SeqHPV. Of the 273 hrHPV-positive cases, 108 had a disease end point of cervical intraepithelial neoplasia grade 2 (CIN2) or higher, including 47 with cervical intraepithelial neoplasia grade 3 (CIN3+) or higher. We simulated the VALGENT framework for inter- and intralaboratory validation and evaluated the new 4-channel risk-stratified ScreenFire assay in a hierarchal fashion. RESULTS: Both AmpFire and ScreenFire detected 106 (98.1%) of 108 cases with CIN2 or higher, with specificities of 56.7% and 58.1%, respectively. Intralaboratory concordance for 2 runs of AmpFire and ScreenFire was 95.13% and 96.03%, respectively, for overall hrHPV types and 99.10% and 99.46%, respectively, for HPV 16. The interlaboratory concordance of AmpFire and ScreenFire was 93.68% and 94.04% for overall hrHPV and 98.92% and 99.28%, respectively, for HPV 16. Other genotype correlation percentages were similarly high, with κs ranging from 0.86 to 0.94. The ScreenFire RS assay demonstrated excellent "genotype-specific concordance" when evaluated for "clinical guidance" in a hierarchal fashion (noting only the highest risk channel) with both the cobas 4800 and SeqHPV for less than CIN2, CIN2, and CIN3 or higher. CONCLUSIONS: The excellent intra- and interlaboratory reproducibility and the established clinical performance, together with the platforms' simplicity, make these assays particularly applicable to low-resource settings.


Asunto(s)
Infecciones por Papillomavirus , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Humanos , Femenino , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/virología , Neoplasias del Cuello Uterino/diagnóstico , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/virología , Papillomaviridae/genética , Papillomaviridae/aislamiento & purificación , Adulto , Detección Precoz del Cáncer/métodos , Persona de Mediana Edad , Sensibilidad y Especificidad , Tamizaje Masivo/métodos , Reproducibilidad de los Resultados
9.
Sci Rep ; 14(1): 4551, 2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38402302

RESUMEN

The proposed study presents an enhanced combination weighting cloud model for accurate assessment of coal and gas outburst risks. Firstly, a comprehensive evaluation index system for coal and gas outburst risks is established, consisting of primary indicators such as coal rock properties and secondary indicators including 13 factors. Secondly, the improved Analytic Hierarchy Process (IAHP) based on the 3-scale method and the improved CRITIC based on indicator correlation weight determination method are employed to determine subjective and objective weights of evaluation indicators respectively. Additionally, the Lagrange multiplier method is introduced to fuse these weights in order to obtain optimal weights. Subsequently, a prominent danger assessment model is developed based on cloud theory. Finally, using a mine in Hebei Province as an example, the results obtained from IAHP combined with improved CRITIC weighting method are compared with those from traditional AHP method and AHP-CRITIC combination weighting method. The findings demonstrate that among all methods considered, IAHP combined with improved CRITIC exhibits superior performance in terms of distribution expectation Ex, entropy value En, and super entropy He within cloud digital features; thus indicating that the risk level of coal and gas outbursts in this particular mine can be classified as general risk. These evaluation results align well with actual observations thereby validating the effectiveness of this approach. Consequently, this constructed model enables rapid yet accurate determination of coal and gas outburst risks within mines.

10.
Comput Biol Med ; 171: 108142, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38394805

RESUMEN

As the alternative solution to the conventional guidewire, the magnetic robot can help interventionists perform percutaneous coronary intervention (PCI) because magnetic fields are transparent and safe for biological tissues. Despite extensive research on magnetic robots, the exploration of their deflection control for practical applications still requires further research. In this paper, a hierarchical analysis framework (HAF) is proposed to control the magnetic robot's deflection. Six deflection subpatterns are analyzed through HAF, incorporating statistical and regression analyses to establish governing equations of magnetic robots. The performance of the control equations is validated through precise control of the magnetic continuum robot (MCR) and magnet-tipped robot (MTR) in both uniform and gradient magnetic fields. Experimental results show that under the uniform magnetic field, the average root mean square error (RMSE) of governing equation of MCR is 0.08±0.05°, 0.41±0.34°, 1.47±0.49° and 1.07±0.66° for four-types horizontal deflection, 0.19±0.07mm and 0.16±0.10mm for two-types vertical deflection, respectively. Based on the governing equations, the MTR is able to precisely navigate to coronary arteries with various degrees of stenosis (30%, 52%, and 60%), and successfully pass through a series of rings, with an average error of 1.05 mm. The research successfully demonstrates the potential of HAF in creating robust and reliable governing equations for magnetic actuation in medical robotics, with significant implications for enhancing the precision and safety of PCI procedures.


Asunto(s)
Intervención Coronaria Percutánea , Robótica , Robótica/métodos , Campos Magnéticos , Imanes , Diseño de Equipo
11.
Int J Mol Sci ; 25(4)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38396790

RESUMEN

Platelet-activating factor (PAF) is a phospholipid-derived inflammatory mediator that triggers various inflammatory conditions, including eosinophil activation and recruitment. This study aimed to evaluate the expressions of PAF-metabolism-associated genes, namely genes coding the enzymes involved in PAF synthesis (LPCAT1, LPCAT2, LPCAT3, and LPCAT4), PAF degradation (PAFAH1B2, PAFAH1B3, and PAFAH2), and the gene for the PAF receptor (PTAFR) in subtypes of CRSwNP classified by clinical- or hierarchal-analysis-based classifications. Transcriptomic analysis using bulk RNA barcoding and sequencing (BRB-seq) was performed with CRSwNP, including eosinophilic CRS (ECRS) (n = 9), nonECRS (n = 8), ECRS with aspirin-exacerbated respiratory disease (Asp) (n = 3), and controls with a normal uncinate process mucosa (n = 6). PTAFR was only upregulated in ECRS and nonECRS. In the hierarchical cluster analysis with clusters 1 and 2 reflecting patients with low-to-moderate and high levels of type 2 inflammation, respectively, cluster 1 exhibited a significant downregulation of LPCAT2 and an upregulation of PTAFR expression, while cluster 2 showed an upregulation of LPCAT1, PAFAH1B2, and PTAFR and downregulation of PAFAH2 expression. Understanding this strong PAF-associated pathophysiology in the severe type 2 inflammation group could provide valuable insights into the treatment and management of CRSwNP.


Asunto(s)
Pólipos Nasales , Rinitis , Rinosinusitis , Sinusitis , Humanos , Rinitis/patología , Factor de Activación Plaquetaria/genética , Factor de Activación Plaquetaria/metabolismo , Mucosa Nasal/metabolismo , ARN/metabolismo , Pólipos Nasales/patología , Sinusitis/metabolismo , Inflamación/metabolismo , Enfermedad Crónica , Análisis por Conglomerados , Eosinófilos/metabolismo
12.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-1031462

RESUMEN

ObjectiveTo construct traditional Chinese medicine (TCM) diagnostic scale of turbid toxin syndrome in order to provide corresponding reference for the standardization of TCM syndromes and studies. MethodsWe systematically searched the Chinese Medical Dictionary (CMD), China Knowledge Network (CNKI), Wanfang Data Knowledge Service Platform (WF) and VIP database for TCM classics and modern literature on turbid toxin syndrome, and initially screened the four diagnosis information of turbid toxin syndrome, established a pool of information entries, and conducted a cross-sectional clinical survey. Discrete trend method, correlation coefficient method, Cronbach's coefficient method, and factor analysis method were applied to objectively screen the entries. The diagnostic scale of turbid toxin syndrome were constructed through three rounds of Delphi method expert survey to determine the scale entries, using hierarchical analysis to get the judgement matrix scores and relative weight of each entry, after passing consistency test and then isometric expansion of the relative weight of the entries to get the weight of each entry and assign the value. ResultsA total of 35 articles were included, 45 entries were obtained after the initial screening. After the clinical investigation, 12 entries were not suitable by the discrete trend method, 23 entries not suitable by correlation coefficient method, 13 entries by the internal consistency screening were removed with the Cronbach's alpha coefficient rising, and 10 entries not suitable by the factor analysis method. Twenty-two entries were retained after objective screening by the combined use of the four statistical methods. The positive coefficients of experts in the three rounds of Delphi method of expert consultation were 96.67%, the coefficients of expert authority were 0.834, 0.856, and 0.867, and the coefficients of co-ordination were 0.126, 0.326, and 0.312, respectively. After consulting with clinical experts, and three rounds of Delphi method survey and hierarchical analysis method weight assignment, the diagnostic scale entries of turbid toxin syndrome were finally established. Primary symptoms: dark red or purple and dusky tongue, yellowish greasy or dry coating (10 points); sticky and unpleasant stools (8 points); disharmony of tastes including halitosis, sticky and greasy taste in the mouth, dry mouth and bitter taste in the mouth (6 points); unfavourable or yellowish or red urination (5 points); and dark complexion (4 points). Secondary symptoms: heavy body (3 points); dizziness (3 points); profuse, sticky, foul-smelling secretions (2 points); wiry and slippery, or slippery, or slippery and rapid pulse (2 points); feeling of hardness in the abdomen (1 point). ConclusionUsing Delphi method combined with the hierarchical analysis method, combining qualitative and quantitative study, a diagnostic scale of turbid toxin syndrome was initially developed.

13.
Acta Crystallogr A Found Adv ; 80(Pt 1): 65-71, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-37955517

RESUMEN

Topological analysis of crystal structures faces the problem of the `correct' or the `best' assignment of bonds to atoms, which is often ambiguous. A hierarchical scheme is used where any crystal structure is described as a set of topological representations, each of which corresponds to a particular assignment of bonds encoded by a periodic net. In this set, two limiting nets are distinguished, complete and skeletal, which contain, respectively, all possible bonds and the minimal number of bonds required to keep the structure periodicity. Special attention is paid to the skeletal net since it describes the connectivity of a crystal structure in the simplest way, thus enabling one to find unobvious relations between crystalline substances of different composition and architecture. The tools for the automated hierarchical topological analysis have been implemented in the program package ToposPro. Examples, which illustrate the advantages of such analysis, are considered for a number of classes of crystalline substances: elements, intermetallics, ionic and coordination compounds, and molecular crystals. General provisions of the application of the skeletal net concept are also discussed.

14.
BMC Public Health ; 23(1): 2009, 2023 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-37845650

RESUMEN

INTRODUCTION: Needlestick injuries (NSIs) are a major hazard in the workplace for healthcare workers. To prevent these injuries, it is essential to determine the important factors affecting the occurrence of them. This study aimed to identify, classify and prioritize these factors using techniques of Delphi and fuzzy analytical hierarchy process (FAHP). METHODS: This descriptive-analytical study was conducted in 2022. Firstly, the factors affecting the occurrence of needlestick injuries were identified by the literature review. Moreover, the Delphi technique was used to identify the factors. 20 experts (physicians, nurses, and occupational health experts) participated in the steps of the Delphi method. Then, these factors were grouped into six groups. In the next step, the fuzzy analytical hierarchy process (FAHP) was applied to prioritize the factors. For this purpose, the pairwise comparison questionnaire was designed and filled out by 20 experts. Finally, data were analyzed using MATLAB software (version 2018a). RESULTS: 42 factors (31 factors extracted from the literature review and 11 factors obtained from the Delphi technique) were identified in this study. These factors were categorized into six groups. Based on the results, the relative weight of non-demographic personal factors, tool and technology factors, job factors, organizational factors, demographic personal factors, and environmental factors were computed by 0.200, 0.185, 0.184, 0.157, 0.142, and 0.133, respectively. CONCLUSION: These results determined the importance of the factors affecting the occurrence of needlestick injuries. These findings can be useful for planning preventive measures.


Asunto(s)
Lesiones por Pinchazo de Aguja , Salud Laboral , Médicos , Humanos , Lesiones por Pinchazo de Aguja/epidemiología , Proceso de Jerarquía Analítica , Personal de Salud
15.
Ecol Appl ; 33(4): e2821, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36806368

RESUMEN

Invasive species science has focused heavily on the invasive agent. However, management to protect native species also requires a proactive approach focused on resident communities and the features affecting their vulnerability to invasion impacts. Vulnerability is likely the result of factors acting across spatial scales, from local to regional, and it is the combined effects of these factors that will determine the magnitude of vulnerability. Here, we introduce an analytical framework that quantifies the scale-dependent impact of biological invasions on native richness from the shape of the native species-area relationship (SAR). We leveraged newly available, biogeographically extensive vegetation data from the U.S. National Ecological Observatory Network to assess plant community vulnerability to invasion impact as a function of factors acting across scales. We analyzed more than 1000 SARs widely distributed across the USA along environmental gradients and under different levels of non-native plant cover. Decreases in native richness were consistently associated with non-native species cover, but native richness was compromised only at relatively high levels of non-native cover. After accounting for variation in baseline ecosystem diversity, net primary productivity, and human modification, ecoregions that were colder and wetter were most vulnerable to losses of native plant species at the local level, while warmer and wetter areas were most susceptible at the landscape level. We also document how the combined effects of cross-scale factors result in a heterogeneous spatial pattern of vulnerability. This pattern could not be predicted by analyses at any single scale, underscoring the importance of accounting for factors acting across scales. Simultaneously assessing differences in vulnerability between distinct plant communities at local, landscape, and regional scales provided outputs that can be used to inform policy and management aimed at reducing vulnerability to the impact of plant invasions.


Asunto(s)
Biodiversidad , Ecosistema , Humanos , Especies Introducidas , Plantas , Geografía
16.
Environ Monit Assess ; 195(3): 384, 2023 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-36763310

RESUMEN

Land use change and ecological sensitivity studies are relevant to the dynamic stability of the overall regional ecological environment. In this study, Nanyang City, a South-North Water Transfer water source area, was used as the study area to analyse land use changes and landscape pattern changes in Nanyang City from 1990 to 2020 based on land use data. Hierarchical analysis (AHP method) was used and combined with six sensitivity factors to conduct a multi-factor comprehensive ecological sensitivity evaluation of Nanyang City. The results show that: (1) between 1990 and 2020, the transfer of water and construction land in Nanyang City was larger, increasing by 30.25% and 99.56% respectively, with a small decrease in the area of cultivated land and a small increase in the area of forest land; the overall rate of land use change in Nanyang City during the 30-year period was first slow and then fast. (2) At the level of patch types, the fragmentation of cultivated land and construction land is the highest; during the study period, the overall fragmentation of the study area tends to decrease; at the level of landscape, each landscape type develops in the direction of equilibrium. (3) The ecological sensitivity increases gradually from the urban cluster in the central plain area to the periphery, with the highly sensitive areas distributed in the water area, the medium sensitive areas in the mountainous area, and the low sensitive areas and insensitive areas in the cultivated land and town planning area.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Agua , Monitoreo del Ambiente/métodos , Bosques , Ciudades , China
17.
Environ Sci Pollut Res Int ; 30(6): 14091-14103, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36571682

RESUMEN

Top coal caving is a process for the rational extraction of large amounts of coal resources. However, this process readily causes release of excessive amounts of gangue during the coal release process. The conventional technique, which involves visual inspection, is not only labor-intensive but also can introduce inaccuracies. Coal and gangue identification methods used during the top coal caving process are reviewed herein. The methods developed and studied over the last 20 years, such as gamma identification, acoustic identification, radar detection, vibration technology, image identification, and infrared positioning, are described separately, and their principles for use are explained. The advantages and disadvantages of these methods are analyzed, and an evaluation index for coal gangue identification methods is established by using hierarchical analysis (AHP). The results indicate that the γ-ray method is optimal to use under the current system. A future gangue identification method is conceived and proposed, which has reference value for the research and applications of gangue identification technology.


Asunto(s)
Carbón Mineral , Carbón Mineral/análisis , China
18.
Artículo en Inglés | MEDLINE | ID: mdl-36554734

RESUMEN

In the post-epidemic era, there is an endless supply of epidemic prevention products that cover a wide range of public areas. The introduction of such products has eased the tense pattern of virus proliferation in the context of the epidemic, and effectively demonstrated the initiatives implemented by the Chinese people in response to the outbreak. This paper therefore begins with the study of contactless epidemic prevention products, which appear in a form that meets the needs of contemporary society and offers a new mode of living to it. It enriches the measures for epidemic prevention and control. By obtaining satisfaction ratings from the user community, the performance of such products can be understood in time to provide a substantial basis for the subsequent upgrading and optimization or transformation of such products. This study uses the KJ method and questionnaires to construct an index system for contactless epidemic prevention products, grasp users' needs for epidemic prevention products in real time, classify and identify such products, and select such products as epidemic prevention smart security gates, medical delivery robots, infrared handheld thermometers, thermographic body temperature screening, contactless inductive lift buttons, and contactless medical vending machines. The questionnaire was designed with four dimensions: safety, intelligence, aesthetics and economy. A sample size of 262 was collected through the distribution of questionnaires. We used AHP and entropy weighting methods for the comprehensive evaluation; AHP basically tells us how satisfied most users are with this type of product. The use of the entropy weighting method can achieve objectivity in the weighting process. Combining the two approaches helps to improve the scientific nature of the weighting of the evaluation indexes for contactless and epidemic-proof products. It is clear from the AHP analysis that, firstly, there are differences in the perceptions of the performance of this type of product between different age groups. Secondly, the user group rated the perceived performance of the product presented as high (Bn>0.200), which users can subjectively and directly perceive. Next, the perceived future sustainable economic development of this product category is low (Bn≤0.200), and users place low importance on its economic aspects as an objective additional condition. The entropy method of analysis shows that, under reasonable government control of the market for intelligent products, the safety, intelligence and aesthetic effects of these products are significant (Cm≤0.100); further, the economic presentation of these products has yet to be optimized and upgraded (Cm>0.100).


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Entropía , Encuestas y Cuestionarios
19.
Heliyon ; 8(11): e11629, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36439750

RESUMEN

As a new, high-strength and clean cast iron material, nitrogen-containing gray cast iron has excellent properties and a wide range of application prospects. However, the excellent material properties of the material not only make the machinability challenging, but also the high efficiency and quality of the machining process is a pressing issue. Therefore, it is necessary to study the machining characteristics of nitrogen-containing gray cast iron to obtain the optimal machining parameters to enrich the research work on nitrogen-containing gray cast iron. In this paper, the machining characteristics of nitrogen-containing gray cast iron are systematically studied, and the effects of cutting parameters on milling force, milling temperature, and surface roughness are analyzed. And, based on the machinability assessment, the objective function weights under different production requirements are determined by using hierarchical analysis trade-offs, and an integrated optimization model based on non-dominated ranking genetic algorithm and hierarchical analysis (AHP) is proposed. The model outputs the optimal combination of milling parameters by inputting the cutting speed (vc), feed rate per tooth (fz) and cutting depth (ap), surface roughness and cutting efficiency as the objective functions. The experimental results show that cutting depth has the greatest effect on the cutting force and cutting speed has the greatest effect on the cutting temperature and the surface roughness. The passivation effect of nitrogen on the graphite tip resulted in an increase in both cutting force and cutting temperature. The parameter optimization results indicated that the optimized roughing parameters significantly improve the surface quality while machining efficiently; the optimized finishing parameters improve Ra by 23.53% while ensuring higher MRR, which can achieve efficient and high-quality machining under different production requirements and provide an experimental basis for practical engineering applications of nitrogen-containing gray cast iron.

20.
Front Nutr ; 9: 991907, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36276824

RESUMEN

Objective: Metabolic syndrome (MetS) is a global problem that increasingly violates human health and quality of life. We explored the relationship between dietary inflammatory potential represented by dietary inflammatory index (DII) and the occurrence of MetS to provid data support for the prevention of it through dietary structure intervention. Methods: The data was come from National Health and Nutrition Examination Survey 2007-2018, including demographic, dietary, questionnaire variables and laboratory indicators. MetS was defined according to the criteria proposed by the American Endocrine Association (ACE) and the American Society of Clinical Endocrinology (ACCE). DII was calculated using the scoring method established by Shivappa. We divided DII scores into 4 quartiles, the chi-square test was used to compare the variable difference between DII quartiles groups. A logistic regression model was used to analyze the association between DII and MetS. We also performed subgroup analysis. A generalized linear regression model was used to explore the association of DII level and the levels of seven MetS related biochemical indicators. Results: The final sample size was 8,180, and the DII scores of the subjects were -5.50 to 5.22. The proportions of men, young people, non-Hispanic blacks, poor people, smokers, and MetS patients in the Q1-Q4 DII quantiles groups were gradually increased. The risk of MetS in the Q4 group which had highest dietary inflammatory degree was 1.592 (1.248, 2.030) times higher than that in the Q1 group, respectively (P < 0.001). After subgroup analysis, women, youth, non-smokers and alcohol drinkers were found to be more sensitive to the dietary inflammation. Then we found that the level of DII was significantly positively correlated with waist circumference (WC), body mass index (BMI), triglyceride (TG), systolic blood pressure (SBP) and diastolic blood pressure (DBP), but negatively correlated with high density lipoprotein cholesterol (HDL-C). Conclusions: In the research subjects, the degree of dietary inflammation was associated with the occurrence of MetS and significantly affected WC, BMI, blood pressure, and blood lipid levels. It is necessary to conduct investigations and early dietary interventions for women and young people to prevent the occurrence of chronic metabolic diseases.

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