average characteristic
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2021 ◽  
Vol 28 (5) ◽  
Author(s):  
I. V. Korablina ◽  
T. O. Barabashin ◽  
N. I. Katalevsky ◽  
◽  
◽  
...  

Purpose. The study is aimed at investigating metal accumulation in the 0–2 cm layer of the bottom sediments of the Black Sea northwestern shelf over 2000–2020, and at identifying the sea bottom areas subjected to the increased anthropogenic load through comprehensive assessment of the degree of their pollution taking into account their granulometric composition. Methods and Results. The bottom sediments were sampled annually from the 0–2 cm depth at the same stations. The detected metal concentrations were compared with their content in the Earth crust and the background values. The dynamics and trends of the individual metals’ content in the shelf bottom sediments were assessed for the whole period of observations. The notion of the average characteristic concentration of an element is introduced; the procedure for its calculation is represented. The pollution of bottom sediments was analyzed with the regard for the element average characteristic concentration in the bottom sediments of various granulometric types. Increase in the average content of lead, zinc and chromium was revealed from the beginning of the observation period to 2020. The seasonal dynamics of these elements was found in the whole water area under study (as well as the iron content at some areas). Conclusions. Multiple cases of the lead, manganese and chrome concentrations exceeding their content in the Earth crust were recorded; as for zinc and copper, such cases were few and sporadic. The tendencies in variation of the bottom sediments content were determined: the average long-term values of the lead concentration increased by 1.2 times, those of zinc – by 1.6 times, and those of chrome – by 2 times; the concentrations of iron, manganese and copper remained essentially the same. Seasonal dynamics of the zinc, chromium, lead and iron content was shown. For a number of metals, the cases when their absolute content exceeded their average characteristic concentration in the corresponding type of the bottom sediments had been found. The regions subjected to a multi-faceted anthropogenic load were identified; the areas of possible local inflow of the monitored elements were revealed. The bottom sediments sampled in 2019 were the most polluted.


Atmosphere ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 5
Author(s):  
Álvaro Gómez-Losada ◽  
José C. M. Pires

North African dust intrusions can contribute to exceedances of the European PM10 and PM2.5 limit values and World Health Organisation standards, diminishing air quality, and increased mortality and morbidity at higher concentrations. In this study, the contribution of North African dust in Mediterranean countries was estimated using the time series clustering method. This method combines the non-parametric approach of Hidden Markov Models for studying time series, and the definition of different air pollution profiles (regimes of concentration). Using this approach, PM10 and PM2.5 time series obtained at background monitoring stations from seven countries were analysed from 2015 to 2018. The average characteristic contributions to PM10 were estimated as 11.6 ± 10.3 µg·m−3 (Bosnia and Herzegovina), 8.8 ± 7.5 µg·m−3 (Spain), 7.0 ± 6.2 µg·m−3 (France), 8.1 ± 5.9 µg·m−3 (Croatia), 7.5 ± 5.5 µg·m−3 (Italy), 8.1 ± 7.0 µg·m−3 (Portugal), and 17.0 ± 9.8 µg·m−3 (Turkey). For PM2.5, estimated contributions were 4.1 ± 3.5 µg·m−3 (Spain), 6.0 ± 4.8 µg·m−3 (France), 9.1 ± 6.4 µg·m−3 (Croatia), 5.2 ± 3.8 µg·m−3 (Italy), 6.0 ± 4.4 µg·m−3 (Portugal), and 9.0 ± 5.6 µg·m−3 (Turkey). The observed PM2.5/PM10 ratios were between 0.36 and 0.69, and their seasonal variation was characterised, presenting higher values in colder months. Principal component analysis enabled the association of background sites based on their estimated PM10 and PM2.5 pollution profiles.


Universe ◽  
2020 ◽  
Vol 6 (11) ◽  
pp. 215
Author(s):  
Maxim Nikonov ◽  
Mikhail Chekal ◽  
Stanislav Shirokov ◽  
Andrey Baryshev ◽  
Vladimir Gorokhov

New observations of high-redshift objects are crucial for the improvement of the standard ΛCDM cosmological model and our understanding of the Universe. One of the main directions of modern observational cosmology is the analysis of the large-scale structure of Universe, in particular, in deep fields. We study the large-scale structure of the Universe along the line of sight using the latest version of the COSMOS2015 catalogue, which contains 518,404 high quality photometric redshifts of galaxies selected in the optical range of the COSMOS field (2×2 deg2), with depth up to the redshift z∼6. We analyze large-scale fluctuations in the number of galaxies along the line of sight and provide an estimate of the average linear sizes of the self-correlating fluctuations (structures) in independent redshift bins of Δz=0.1 along with the estimate of the standard deviation from homogeneity (the observed cosmic variance). We suggest a new method of the line-of-sight analysis based on previous works and formulate further prospects of method development. For the case of the theoretical form of approximation of homogeneity in the ΛCDM framework, the average standard deviation of detected structures from homogeneity is σmeanΛCDM=0.09±0.02, and the average characteristic size of structures is RmeanΛCDM=790±150 Mpc. For the case of the empirical approximation of homogeneity, the average standard deviation of detected structures from homogeneity is σmeanempiric=0.08±0.01, and the average characteristic size of structures is Rmeanempiric=640±140 Mpc.


2020 ◽  
Vol 77 (15) ◽  
pp. 1237-1242
Author(s):  
Sara A Atyia ◽  
Frank P Paloucek ◽  
Allison R Butts ◽  
Douglas R Oyler ◽  
Craig A Martin ◽  
...  

Abstract Purpose The disparity between the number of applicants for postgraduate year 1 (PGY1) pharmacy residency positions and the number of available residency positions increases the need to optimize how applicants are evaluated. The purpose of the study described here was to evaluate the correlation of ratings of residency candidate characteristics by academic and professional references listed on residency applications with overall application score, applicant ranking, and the likelihood of candidates receiving an invitation to interview. Methods A multicenter, retrospective study was conducted to evaluate the correlation of reference writers’ ratings of 13 candidate characteristics and their overall recommendations with program-determined outcomes (eg, final application score, applicant ranking, and invitation to interview) through analysis of PGY1 applications submitted through the Pharmacy Online Residency Centralized Application System (PhORCAS) from 2015 through 2018. Keywords and themes within the open-ended section of letters of reference were also analyzed for correlation with overall application score. Results A total of 5,923 references listed on 1,867 applications to 4 PGY1 pharmacy residency programs processed by PhORCAS were included in the analysis. For the majority of applicant characteristic ratings (ie, 74% of 56,872 ratings overall), reference writers rated candidates as exceeding expectations, and applicants were “highly recommended” by these evaluators in 91% of cases. References’ average characteristic ratings and overall recommendations were poorly correlated with final application score (R2 = 0.12 [P < 0.0001] and R2 = 0.08 [P < 0.0001], respectively), final ranking (R2 = 0.02 [P < 0.0001] and R2 = 0.03 [P < 0.0001], respectively), and invitation to interview (R2 = 0.07 [P < 0.0001] and R2 = 0.04 [P < 0.0001], respectively). For the themes evaluated, references’ use of teaching words best correlated with normalized final application score, although the correlation was poor (R2 = 0.007, P = 0.0001). Conclusion Reference writers’ ratings of PGY1 residency candidate characteristics in PhORCAS are poorly correlated with application score, applicant ranking, and invitation to interview. The results of this study suggest that the existing PhORCAS standardized form for submitting references is of limited utility in its current state.


Author(s):  
Jumei Xu ◽  
Zhongkai Jiang ◽  
Zuoxiang Zeng ◽  
Weilan Xue

The adsorption behavior of sodium bisulfate on silica gel was studied. The adsorption isothem of sodium hydrogen sulfate on silica gel were measured in the temperature range of 298.15 ~ 328.15 K, and the Langmuir model and the Dubini-Radushkevich (D-R) model were used to fit the experimental isotherm data. The average characteristic concentration (Ce') of NaHSO4 was determined at different temperatures to distinguish chemisorption from physisorption. The values of the mean free energy (E) calculated from the D−R isotherm equation indicated that the adsorption of NaHSO4 on silica gel occurs by sequential chemical and physical mechanisms.


Author(s):  
Indrani Dalui ◽  
SurajitGoon ◽  
Avisek Chatterjee

Fractal image compression depends on self-similarity, where one segment of a image is like the other one segment of a similar picture. Fractal coding is constantly connected to grey level images. The simplest technique to encode a color image by gray- scale fractal image coding algorithm is to part the RGB color image into three Channels - red, green and blue, and compress them independently by regarding each color segment as a specific gray-scale image. The colorimetric association of RGB color pictures is examined through the calculation of the relationship essential of their three-dimensional histogram. For normal color images, as a typical conduct, the connection necessary is found to pursue a power law, with a non- integer exponent type of a given image. This conduct recognizes a fractal or multiscale self-comparable sharing of the colors contained, in average characteristic pictures. This finding of a conceivable fractal structure in the colorimetric association of regular images complement other fractal properties recently saw in their spatial association. Such fractal colorimetric properties might be useful to the characterization and demonstrating of natural images, and may add to advance in vision. The outcomes got demonstrate that the fractal-based compression for the color image fills in similarly with respect to the color image.


2019 ◽  
Vol 35 ◽  
pp. 365-375
Author(s):  
Matt Hudelson ◽  
Judi McDonald ◽  
Enzo Wendler

B. Shader and W. So introduced the idea of the skew adjacency matrix. Their idea was to give an orientation to a simple undirected graph G from which a skew adjacency matrix S(G) is created. The -adjacency matrix extends this idea to an arbitrary field F. To study the underlying undirected graph, the average -characteristic polynomial can be created by averaging the characteristic polynomials over all the possible orientations. In particular, a Harary-Sachs theorem for the average-characteristic polynomial is derived and used to determine a few features of the graph from the average-characteristic polynomial.


2019 ◽  
Vol 4 (1) ◽  
pp. 106-112
Author(s):  
Sergey Mikhailuta ◽  
Anatoly Lezhenin ◽  
Pavel Gudovsky

The paper presents the results of a full-scale survey of the urban air pollution in industrial and residential areas of the Krasnoyarsk. The features of the spatial distribution of acetaldehyde concentrations in the atmospheric air on the territory of Krasnoyarsk are shown. The average, characteristic level of acetaldehyde in residential areas is more than 10 µg / m3, and in industrial areas it reaches values more than 140 µg / m3.


2018 ◽  
Vol 42 (3) ◽  
Author(s):  
Yusuf Kurniawan ◽  
Rukmiasih Rukmiasih ◽  
Mokhamad Fahrudin ◽  
Peni Soeprapti Hardjosworo

The study was conducted to analyze the characteristic of eggs (temperature of eggshell, weight loss, and air sac alteration) at various hatching period of local duck hatched (H) and unhatched (UH) at the final observation, and to find out the effective time for estimating the life of embryo during the end of incubation. A total of 146 eggs were incubated and observed between 1 and 25 days of incubation (DOI). The results of weight loss and air sac change showed a significant difference (P<0,05) between H and UH eggs on 7 to 25 DOI, while the temperature of eggshell was only different on 25 DOI. The average characteristic of H group (temperature of eggshell, weight loss, and air sac alteration) on 25 DOI was recorded 38,46oC, 11,84%, and 51,03%, respectively. It can be concluded that 3 characteristics of eggs influence hatchability of local duck. Weight loss and air sac alteration parameters can be applyed to estimate the hatched eggs between 7 and 25 DOI, but the temperature of eggshell can be administrated after 25 DOI.


2018 ◽  
Vol 85 (6) ◽  
pp. 36-39
Author(s):  
V. І. Lyakhovskyi ◽  
А. V. Sydorenko ◽  
R. P. Sakevych ◽  
О. М. Bezkorovaynyу ◽  
R. М. Rіabushko ◽  
...  

Objective. To estimate the causes of occurrence and quality of diagnosis of false aneurisms (FA) of femoral arteries after endovascular interventions. Маterials and methods. In Poltava Regional Clinical Hospital named after М. V. Sklifosovskyi in 2008 - 2017 yrs in 7237 patients 10 783 punctures of femoral arteries were performed for conduction of the diagnosis and treatment interventions in cardiological patients (Group I) and in patients, suffering occlusion-stenotic diseases of main arteries of the lower extremities (Group II). In 57 (0.79%) patients the FA of femoral arteries were revealed. All the patients were examined, using ultrasonographic color angioscanning (USCAS). Встановлені причини виникнення ХА та особливості їх діагностики. Results. FA of femoral artery was revealed on the (2.65 ± 2.31) day after the introducer extraction at average. Characteristic complaints had 45 (78.9%) patients. Using USCAS there were revealed the puncture site, the aneurism form, its spread and volume. Local and general factors, promoting development of postpunctural FA, were revealed. Conclusion. For the FA development prophylaxis it is mandatory to perform a femoral artery puncture under the USCAS control with a precise localization of the puncture performance site. In the patients with pronounced signs of hypertonic disease and obesity after conduction of a thrombolytic therapy it is expedient to use widely the apparatus for the hemorrhage arrest of the Angio Seal type under ultrasonographic control. On the first day after the introducer extraction it is obligatory to conduct a control USCAS procedure of a puncture site. In a case of diagnosis of transmural wounding of the artery and the aneurism formation the open-access urgent operative intervention must be performed.


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