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2021 ◽  
Vol 14 (1) ◽  
pp. 156
Author(s):  
Mirel Pop ◽  
Iulia Bucur ◽  
Dan Zoldan ◽  
Kálmán Imre ◽  
Ileana Nichita ◽  
...  

The aim of this study was to assess the microbiological and chemical air quality in a municipal solid waste landfill and its inhabited surroundings, in a particular context in which Romania struggles with the incapacity to comply with its environmental commitments. The research was conducted on a landfill near the capital Bucharest between November 2018 and September 2019. To evaluate the chemical (oxygen, carbon dioxide, methane, hydrogen sulfide, ammonia and carbon monoxide–MX6 iBrid™ Détector multigas) and microbiological (airborne bacteria and fungi–aspiration method) parameters, eight sampling points were established, located both on the perimeter of the landfill and within its surroundings. CO and CH4 were not detected in any of the sampling points, during the study period; O2 was in normal values 20.09–21.05%; CO2 had a maximum average concentration of 620 ± 215; H2S had values between 0.1 and 5.0 ppm only in the sampling points inside the landfill; NH3 was present only once in a single sampling point with values between 1.0 and 3.0 ppm. The microbiological results provide an overview of the total plate count and total fungal count, with no significant differences between the level of contamination inside the landfill and within its surroundings (p > 0.05). Ten bacterial species and fungi from six genera have been identified. It was also found that the number of microorganisms in the air was significantly lower during the winter, spring and early summer months compared with the late summer and autumn months (p < 0.05).


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Zhiqiang Liu ◽  
Bo Xu ◽  
Bo Cheng ◽  
Xiaomei Hu

Although DEM occupies an important basic position in spatial analysis, so far, the quality of DEM modeling has still not reached a satisfactory accuracy. This research mainly discusses the influence of interpolation parameters in the inverse distance-weighted interpolation algorithm on the DEM interpolation error. The interpolation parameters to be studied in this paper are the number of search points, the search direction, and the smoothness factor. In order to study the optimization of IDW parameters, the parameters that have uncertain effects on DEM interpolation are found through analysis, such as the number of search points and smoothing factor. This paper designs an experiment for the optimization of the interpolation parameters of the polyhedral function and finds the optimal interpolation parameters through experimental analysis. Of course, the “optimum” here is not the only one, but refers to different terrain areas, which makes the interpolation results relatively good. The selection of search points will be one of the research focuses of this article. After determining the interpolation algorithm, the kernel function is also one of the important factors that affect the accuracy of DEM. The value of the smoothing factor in the kernel function has always been the focus of DEM interpolation research. Different terrains, different interpolations, and functions will have different optimal smoothing factors. The search direction is to ensure that the sampling points are distributed in all directions when the sampling points are sparse and to improve the contribution rate of the sampling points to the interpolation points. The selection of search shape is to improve computing efficiency and has no effect on DEM accuracy; the search radius is mainly controlled by the number of search points, and there are two methods: adaptive search radius and variable length search radius. When the weight coefficient k = 1 , 2 , 3 , 4 , the number of sampling points involved in the interpolation calculation is different, and the error in the residual varies greatly, and both increase with the increase of the number of sampling points in the parameter interpolation calculation. This research will help improve the quality evaluation of DEM.


Author(s):  
Kang Gu ◽  
Sheng Chen ◽  
Xiaoyu You ◽  
Yifei Li ◽  
Jianwei Cui ◽  
...  

Abstract The coordinate measuring machine (CMM) becomes an extensive and effective method for high precision inspection of free-form surfaces due to its ability to measure complex and irregular surfaces. Sampling strategy and surface restoration method have an important influence on the efficiency and precision of CMM. In this paper, a sparse sampling strategy and surface reconstruction method for free-form surfaces based on low-rank matrix completion (LRMC) is proposed. In this method, the free-form surface is sampled randomly with uniform distribution in the cartesian coordinate system to obtain sparse sampling points, and then optimizes the scanning path to obtain the shortest path through all measurement points, and finally, the LRMC algorithm based on alternating root mean square prop was used to reconstruct the surface with high precision. The simulation and experimental results show that under the premise of ensuring accuracy, the number of sampling points is greatly reduced and the measurement efficiency is greatly improved.


Author(s):  
K. Arun Kumar ◽  
B. S. Shilpa ◽  
S. Sandeep

Among air pollution control strategies, air cleaning with Advanced Oxidation Processes (AOPs) has been drawing more and more attention because of the restraints in the production of secondary pollution. AOPs have a wide range of applications such as air (odour elimination, purification), soil (remediation) and water decontamination. Ideally, the photo catalyst, titanium dioxide, is introduced in the top layer of the concrete pavement for best results. In addition, the combination of TiO2 with cement-based products offers some synergistic advantages, as the reaction products can be adsorbed at the surface and subsequently be washed away by rain. The main aim of this research work is to measure the effect of titanium dioxide as photo catalyst in purifying nitrogen oxide (NOX) and Carbon Oxides (COX) on pavement surface and outdoor environment condition. For that, TiO2 is replaced for cement at different proportions of 5%, 10% & 15% in terms of weight in the cement concrete moulds of 10 mm uniform thickness and curing is done for seven days, then same were exposed to the sunlight at Ijoor circle sampling point Rama Nagar Town for 21 days of observation. From the Energy Dispersive Spectroscopy (EDS) analysis, result it is observed that atom percentage increased maximum of 59.05 for carbon atoms for 10% proportion specimen. Then, check the amount of  percentage for carbon atoms adsorbed by 10% proportion specimen at police/Kandaya Bhavan circle and Railway station circle sampling points of Rama Nagar Town for 21 days of observations and the results shows that, carbon atom percentage increased maximum of 42.99 and 58.69 for carbon atoms respectively at above sampling points. From this work, it is conclude that the  Carbon atoms and Nitrogen atoms present in the atmosphere will be reduce up to some level when replace 10% of Titanium dioxide with cement in the concrete  moulds of 10 mm thickness by Photo catalytic activity.


2021 ◽  
Vol 3 (2) ◽  
pp. 107-113
Author(s):  
Gabriel Valentin Serban ◽  
◽  
Marcela Niculescu ◽  
Vasile Iancu ◽  
Iuliana Paun ◽  
...  

The purpose of the paper was to create databases that would allow a proper assessment of the degree of marine pollution generated by the shipyard industrial sector. The study was conducted over a period of three years, between 2015 and 2017. The parameters determined for the waters collected from the shipyard were within the maximum allowed limits according to the norms in force. However, values very close to the maximum allowable limit were observed in the case of groundwater for nickel, determined from the drilling located near the fuel depot in 2015 and chlorides determined from the drilling located near the galvanizing workshop, both in 2016 and in 2017. The analyzed parameters for the soil samples, collected from various sampling points and different depths, were below the value of the alert thresholds for less sensitive soils, according to Order 756/97. The databases created for this study can contribute as an incipient basis for the development of larger studies that include other industrial sectors as well as a longer evaluation period.


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261015
Author(s):  
Zhen Yang ◽  
Chenchen Wang ◽  
Yanwu Nie ◽  
Yahong Sun ◽  
Maozai Tian ◽  
...  

Background and objectives Xinjiang is one of the areas in China with extremely severe iodine deficiency. The health of Xinjiang residents has been endangered for a long time. In order to provide reasonable suggestions for scientific iodine supplementation and improve the health and living standards of the people in Xinjiang, it is necessary to understand the spatial distribution of iodine content in drinking water and explore the influencing factors of spatial heterogeneity of water iodine content distribution. Methods The data of iodine in drinking water arrived from the annual water iodine survey in Xinjiang in 2017. The distribution of iodine content in drinking water in Xinjiang is described from three perspectives: sampling points, districts/counties, and townships/streets. ArcGIS was used for spatial auto-correlation analysis, mapping the distribution of iodine content in drinking water and visualizing the distribution of Geographically Weighted Regression (GWR) model parameter. Kriging method is used to predict the iodine content in water at non-sampling points. GWR software was used to build GWR model in order to find the factors affecting the distribution of iodine content in drinking water. Results There are 3293 sampling points in Xinjiang. The iodine content of drinking water ranges from 0 to 128 μg/L, the median is 4.15 μg/L. The iodine content in 78.6% of total sampling points are less than 10 μg/L, and only that in the 3.4% are more than 40 μg/L. Among 1054 towns’ water samples in Xinjiang, 88.9% of the samples’ water iodine content is less than 10 μg/L. Among the 94 studied areas, the median iodine content in drinking water in 87 areas was less than 10 μg/L, those values in 7 areas were between 10–40 μg/L, and the distribution of water iodine content in Xinjiang shows clustered. The GWR model established had found that the effects of soil type and precipitation on the distribution of iodine content in drinking water were statistically significant. Conclusions The iodine content of drinking water in Xinjiang is generally low, but there are also some areas which their drinking water has high iodine content. Soil type and precipitation are the factors affecting the distribution of drinking water iodine content, and are statistically significant (P<0.05).


PLoS ONE ◽  
2021 ◽  
Vol 16 (12) ◽  
pp. e0261283
Author(s):  
Jeronimo Alencar ◽  
Cecilia Ferreira de Mello ◽  
Paulo José Leite ◽  
Amanda Queiroz Bastos ◽  
Shayenne Olsson Freitas Silva ◽  
...  

The present study aims to analyze the effectiveness of ovitraps in the capture of Hg leucocelaenus eggs and evaluate the influence of the dry and rainy seasons on their abundance and hatching rates. The eggs were collected in the Atlantic Forest of State of Rio de Janeiro, Brazil, an area in which the yellow fever virus is known to circulate. We distributed 15 ovitraps in three sampling points, with five ovitraps per point. We distributed 15 ovitraps in three sampling points on trees within a forested area, which were sequentially numbered, monitored, and replaced every two weeks from October 2016 to April 2018. There was a high dominance of Hg. leucocelaenus eggs (98.4%) and a variation in egg hatching rates between the wet and dry seasons. These rates were 1.5 times higher in the rainy season than in the dry season. The rainy season also showed a greater abundance of eggs and higher values of ovitrap positivity and egg density indexes in the installed ovitraps. The abundances of Hg. leucocelaenus eggs were positively correlated with mean monthly temperature and air humidity but not significantly correlated with accumulated precipitation. These results, as well as their implications for the possible use of ovitraps to monitor vector mosquitoes of yellow fever in the study region, are discussed.


2021 ◽  
Author(s):  
Xiaolei Yan ◽  
Bin Du ◽  
Juan Lu ◽  
Wenkun Zhang

The distribution and changes of constitutional water, immobilized water and free water and the effects of the sorbitol on three kinds of water during the curing of fresh meat were studied in this paper. The low-field Nuclear Magnetic Resonance were used to measure water and its distribution in meat. The test parameters are as follows: magnetic field strength of the NMR spectrometer is 0.5Tesla, corresponding resonance frequency for protons is 22MHz, sampling points is 160128, repeated scanning number is 16, repetition time is 1.6s, echo time is 1.6s. The results showed that: the relaxation time T2 can be divided into three parts: T21 (0∼10ms), T22 (10∼100ms), T23 (100∼1000ms). And the area of T21, T22, T23 represents the contents of constitutional water, immobilized water and free water. The addition of sorbitol can keep water during curing. The sorbitol can reduce the activity of the immobilized water and free water during curing of the fresh meat.


Open Heart ◽  
2021 ◽  
Vol 8 (2) ◽  
pp. e001869
Author(s):  
Ingvild Maria Tøllefsen ◽  
Christian Shetelig ◽  
Ingebjørg Seljeflot ◽  
Jan Eritsland ◽  
Pavel Hoffmann ◽  
...  

ObjectiveInflammation has emerged as a new treatment target in patients with coronary artery disease and inflammation seems to play an important role in ischaemia/reperfusion injury that follows ST-elevation myocardial infarction (STEMI). We aimed to explore the role of acute and sustained interleukin 6 (IL-6) signalling, including soluble IL-6 receptor (IL-6R), with regard to infarct size, adverse remodelling and future cardiovascular events in patients with STEMI.MethodsWe included 269 patients with first-time STEMI, symptom duration <6 hours and treated with percutaneous coronary intervention. Blood sampling and cardiac MRI were performed in the acute phase and after 4 months. Clinical events and all-cause mortality were registered during 12-month and 70-month follow-up, respectively.ResultsIL-6 levels above median at all sampling points were significantly associated with increased infarct size and reduced left ventricular ejection fraction (LVEF). IL-6 levels in the highest quartile were at all sampling points associated with an increased risk of having an adverse clinical event during the first 12 months and with long-term all-cause mortality. IL-6R was not associated with infarct size, LVEF, myocardial salvage or long-term all-cause mortality.ConclusionAcute and sustained elevation of IL-6 measured 4 months after STEMI were associated with larger infarct size, reduced LVEF and adverse clinical events including all-cause mortality. The results add important information to the sustained role of inflammation in patients with STEMI and IL-6 as a potential target for long-term intervention.Trial registration numberNCT00922675.


2021 ◽  
Vol 43 (11) ◽  
pp. 679-687
Author(s):  
Sung Woo Yang ◽  
Seung Hyeon Reo ◽  
Seung Jun Kim ◽  
Jeong Wook Jo ◽  
Yong-Keun Choi ◽  
...  

Objectives : The purpose of this study was to investigate the effect of spitting behavior on microbial public health in smoking areas. Through this investigation, bacterial concentration and spread of bacteria from the smoking areas were evaluated for the prospective public health and environment.Methods : The number of spitting and the spitting location in the smoking areas were measured visually by observers. For the microbial analysis, filter papers (5 × 5 cm) as sample collectors had been attached to the surface of the smoking areas for a given time. Using the collected filter paper, ATP bioluminescence measurement (RLU), colony forming unit (CFU) were measured. For the estimation of spitting behaviors in the smoking area on the spread microorganisms, saliva containing filters were selected from the areas, and fluorescent powder (0.01 g/cm2) was added to the papers. After 4 hours, the papers around the smoking areas were collected and the fluorescence activity was measured.Results and Discussion : The results showed that there was a clear relationship between the spitting behavior and the microbial activity in the smoking areas. In the case of sampling area A, the highest number of spitting was observed at the lunch hour (102 ± 16 times), and the RLU from the sample collected near the smoking area showed about 5,139 ± 1,267 RLU. When the RLU around the smoking area was measured, the lowest values were found at distance of 11 and 17 m from the cigarette bin (1,329 ± 148 and 1,204 ± 203 RLU), and it was confirmed that smoking and spitting did not occur at this sampling points. In the case of sampling area B, the highest number of spitting (45 ± 6 times) was observed at evening hour, and the RLU from the sample collected near the smoking area showed about 5,274 ± 1,297 RLU. The lowest value was in the sampling area B shown at 11 and 18 m (1,181 ± 243 RLU and 1,148 ± 168 RLU) from the cigarette bin, and it was also confirmed that smoking and spitting did not occur at this sampling points. The results indicate that the spitting during the smoking induced the increases of the microbial contamination of the public environment. The fluorescence powder diffusion analysis indicated that the saliva on the ground surface would enhance the spread of the microorganisms from the smoking area.Conclusions : Spitting in smoking areas can pose a high risk of microbial infection for smokers and non-smokers in smoking areas. Thus extensive and systematic attention related to the smoking manner must be paid to protect our public health.


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