scholarly journals Trends of lead in atmospheric air

Author(s):  
S. V. Kakareka

In the article, trends of lead content in atmospheric air of background territories and cities of Belarus according to NSEM data and their correlation with trends of lead content in the atmospheric air of cities and background territories of Europe and the USA are analyzed. Clear downward trends in lead content in the atmospheric air of the background territories of Belarus are shown: the average annual concentration of lead has decreased over the period from 1990 to 2015 by 77 %. According to EMEP stations measuring data having a continuous series of lead observations in atmospheric air since 1990, the mean annual lead content in atmospheric air at these stations decreased till 2013 on average by 86 %. A downward trend in the lead content was observed in the air of Belarusian cities and of some countries of Europe. The most significant decrease in lead content occurred in the USA, where the average annual maximum 3-month concentration decreased from 1990 to 2016 by 99 %. The relationship between trends in lead levels with trends of anthropogenic emissions is analyzed. Differences between the measured lead concentrations and calculated values by dispersion models are shown, which may be due to the incompleteness of the inventory of lead emissions in a number of countries, as well as the significant contribution of other sources of emission in addition to anthropogenic sources of lead emission into the atmosphere. To identify the reasons for these discrepancies, which may be related to the presence of unrecorded anthropogenic sources, secondary and natural sources, and other factors, additional research is needed.

Author(s):  
Mustafa Aydın ◽  
Mehmet Tuğrul Yılmaz ◽  
Muzaffer Şeker

Objectives: The aim of this study was to examine the relationship between the spatial abilities of medical school students and their learning in anatomy. Methods: The spatial abilities of the 120 students (74 females, 46 males) were examined using Mental Rotation Test (MRT). The relationship between the mental rotation scores and the mean scores of their practical and theoretical anatomy examinations was determined in terms of gender. Results: The study revealed that mental rotation skills of female participants were lower than males; however, there was no significant difference in their exam (theoretical and practical anatomy examinations) scores in terms of gender. The spatial ability of the students had a low level significant effect on their anatomy scores, regarding practical applications. Conclusion: The results of the study revealed a significant relationship between students’ spatial ability and their success in practical anatomy examinations. This suggests that improving spatial ability skills may have a significant contribution to practical anatomy learning and may be considered as a part of anatomy education.


2017 ◽  
Vol 17 (3) ◽  
pp. 2217-2227 ◽  
Author(s):  
Nikolay S. Kasimov ◽  
Natalia E. Kosheleva ◽  
Elena M. Nikiforova ◽  
Dmitry V. Vlasov

Abstract. Polycyclic aromatic hydrocarbons (PAHs), particularly benzo[a]pyrene (BaP), are toxic compounds emitted from various anthropogenic sources. Understanding the BaP concentrations, dynamics and decomposition in soil is required to assess the critical loads of BaP in urban environments. This study is the first attempt to evaluate all major input and output components of benzo[a]pyrene (BaP) balance and to calculate the permissible load on the urban environment in different land-use zones in the Eastern district of Moscow. BaP contamination of the snow cover in the Eastern district of Moscow was related to daily BaP fallout from the atmosphere. In 2010, the mean content of the pollutant in the snow dust was 1942 ng g−1, whereas the average intensity of its fallout was 7.13 ng m−2 per day. Across the territory, BaP winter fallout intensities varied from 0.3 to 1100 ng m−2 per day. The average BaP content in the surface (0–10 cm) soil horizons was 409 ng g−1, which is 83 times higher than the local background value and 20 times higher than the maximum permissible concentration (MPC) accepted in Russia. The variations in soil and snow BaP concentrations among different land-use zones were examined. A significant contribution of BaP from the atmosphere to urban soils was identified. Based on the measurements of BaP atmospheric fallout and BaP reserves in the soils, the critical loads of BaP for the land-use zones in the Eastern district were calculated for different values of degradation intensity and different exposure times. It was established that at an annual degradation intensity of 1–10 %, ecologically safe BaP levels in the soils of all land-use zones, excluding the agricultural zone, will only be reached after many decades or centuries.


Author(s):  
Наталья Евгеньевна Купцова

Введение. Представлена совершенно неисследованная тема в отечественном лермонтоведении – академическая рецепция романа М. Ю. Лермонтова «Герой нашего времени» в США. Автор статьи собрала наиболее представительные на сегодняшний день публикации, вышедшие в США за всю историю американского лермонтоведения и посвященные этому роману. Цель – провести исследование академической рецепции романа М. Ю. Лермонтова «Герой нашего времени» в США. Материал и методы. Поиск публикаций, посвященных роману М. Ю. Лермонтова «Герой нашего времени», вышедших в США, и их анализ по предложенной автором периодизации. Результаты и обсуждение. Предложена периодизация по трем периодам: публикации 1900–1960-х гг., публикации 1970–1980-х гг. и публикации 1900-х гг. по настоящее время. Особенностями публикаций 1900–1960-х гг. является прежде всего осмысление того, как М. Ю. Лермонтов изобразил русское общество 1830-х гг. и главного героя своего произведения, акцент на психологичности романа, а также сравнение с героями А. С. Пушкина. Среди исследователей нет согласия относительно жанра романа – так, Мерсеро относит его к жанру психологического реализма, а в предисловии к первому англоязычному изданию в США отмечен байронический характер Печорина. Для публикаций 1970–1980-х гг. наблюдаются совершенно другие акценты у американских исследователей. На первое место выходит интерес к внутреннему устройству романа: его фабуле, сюжету, структуре. Несмотря на то, что по-прежнему нет полного согласия относительно жанровой принадлежности романа, большинство исследователей считают, что именно в роман «Герой нашего времени» покончил с романтизмом в русской прозе, в чем и заключается его главное новаторство. Изменился и взгляд на главного героя романа – в Печорине видят уже не байронические, а демонические черты. На современном этапе изучения романа «Герой нашего времени» у американских исследователей появляются новые темы в изучении романа. Так, например, красной нитью проходит тема отражения в романе взаимоотношений между русскими и кавказскими народами. Кроме того, если раньше в центре внимания исследователей был только Печорин, то теперь изучаются и другие герои и героини романа. Интересно и то, что Печорина теперь считают постромантическим героем и сам роман большинство исследователей считают постромантическим. Заключение. Проведенный анализ и предложенная периодизация наглядно иллюстрируют эволюцию интереса исследователей из США к различным аспектам романа и его героев. Библиографический список статьи внушителен и сам по себе представляет значительный интерес и вклад в лермонтоведение. Авторы публикаций, вошедших в обзор, – филологи, публицисты, политологи и антропологи. Introduction. The article is devoted to the completely unexplored subject in Russian Lermontov studies – the academic reception of the novel “Hero of our time” by the scholars from the USA. In the article the most reputable and representative works published in the USA about this novel are outlined and analyzed in accordance with the following periodization: publications of 1900-1960s, publications of 1970-80s and the modern publications of 1900s until now. The goal. Research of the academic reception of the novel of M. Lermontov «Hero of our time” in the USA. Materials and methods. Search and analysis of the publications, devoted to the novel “Hero of our time” by M. Lermontov issued in the USA in accordance with the periodization proposed by the author. Results and discussion. The focus of publications 1900–1960s is primarily the understanding of how M.Yu. Lermontov portrayed the Russian society of the 1830s and the main character of his work, an emphasis on the psychological nature of the novel, as well as a comparison with A.S. Pushkin. Among the researchers there is no agreement on the genre of the novel - for example, Mercereau classifies it as a genre of psychological realism, and in the preface to the first Russian-language edition in the United States, the Byronic character of Pechorin is noted. In publications from the 1970s to 1980s, there is a completely different emphasis. First of all, the internal structure of the novel is in the focus. Despite the fact that there is still no full agreement on the genre of the novel, most researchers believe that the novel «A Hero of Our Time» that he put an end to romanticism in Russian prose, which is the main innovation of Lermontov. The view on the main character of the novel has also changed - in Pechorin they see not Byronic, but demonic features. At the present stage, American researchers have new topics in the study of the novel «Hero of our time”. For example, the topic of the relationship between the Russian and Caucasian peoples attracts a lot of attention. In addition, if earlier only Pechorin was in the center of attention of researchers, now other heroes and heroines of the novel are also being studied. It is also interesting that Pechorin is now considered a post-romantic hero, and most researchers classify the novel as post-romantic. Conclusion. The conducted analysis and the proposed periodization demonstrably illustrates the evolution of approaches and interest to the various aspects of the novel and its heroes. The bibliography of the article is impressive itself and makes a significant contribution to the Lermontov studies. The authors of the publications included in the review are philologists, publicists, political scientists, anthropologists.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Yingying Xu ◽  
Hui Zhu ◽  
Jie Tang ◽  
Yingzi Lin

Dew and rain water were collected during 2013 and 2014 in Changchun, China. The dew was analyzed and the following parameters were measured: pH, EC, TDS, major anions (F−, Cl−,SO42-, andNO3-), and major cations (NH4+, Na+, K+, Ca2+, and Mg2+). The mean pH, EC, and TDS values of dew were comparable with the values for rainwater. The pH values of dew and rain were 6.72 and 6.16, respectively. Both EC (308 μS/cm) and TDS (154 mg/L) of dew were higher than those in rain samples. The concentration of main ions in dew was 1.5–5.7 times higher than levels in rainwater. The near-neutral pH values in dew were caused by the neutralization of acidity and buffering by the alkaline elements of soil origin (Ca2+). This neutralization was confirmed by a strong correlation between the acidic ions (SO42-andNO3-) and the major cations (Ca2+and Mg2+). Natural dust made an important contribution to the ions present in dews, but the presence of sulfate concentrations that are notably higher than rain water (up to 1584.5 μeq/L) indicated a significant contribution of anthropogenic sources. Dew has the ability to capture particulates, and the purifying effect on the underlying surface was obvious.


2006 ◽  
Vol 18 (4) ◽  
pp. 160-173 ◽  
Author(s):  
Maria Senokozlieva ◽  
Oliver Fischer ◽  
Gary Bente ◽  
Nicole Krämer

Abstract. TV news are essentially cultural phenomena. Previous research suggests that the often-overlooked formal and implicit characteristics of newscasts may be systematically related to culture-specific characteristics. Investigating these characteristics by means of a frame-by-frame content analysis is identified as a particularly promising methodological approach. To examine the relationship between culture and selected formal characteristics of newscasts, we present an explorative study that compares material from the USA, the Arab world, and Germany. Results indicate that there are many significant differences, some of which are in line with expectations derived from cultural specifics. Specifically, we argue that the number of persons presented as well as the context in which they are presented can be interpreted as indicators of Individualism/Collectivism. The conclusions underline the validity of the chosen methodological approach, but also demonstrate the need for more comprehensive and theory-driven category schemes.


1991 ◽  
Vol 65 (03) ◽  
pp. 263-267 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina

SummaryIn a collaborative trial of eleven laboratories which was performed mainly within the framework of the European Community Bureau of Reference (BCR), a second reference material for thromboplastin, rabbit, plain, was calibrated against its predecessor RBT/79. This second reference material (coded CRM 149R) has a mean International Sensitivity Index (ISI) of 1.343 with a standard error of the mean of 0.035. The standard error of the ISI was determined by combination of the standard errors of the ISI of RBT/79 and the slope of the calibration line in this trial.The BCR reference material for thromboplastin, human, plain (coded BCT/099) was also included in this trial for assessment of the long-term stability of the relationship with RBT/79. The results indicated that this relationship has not changed over a period of 8 years. The interlaboratory variation of the slope of the relationship between CRM 149R and RBT/79 was significantly lower than the variation of the slope of the relationship between BCT/099 and RBT/79. In addition to the manual technique, a semi-automatic coagulometer according to Schnitger & Gross was used to determine prothrombin times with CRM 149R. The mean ISI of CRM 149R was not affected by replacement of the manual technique by this particular coagulometer.Two lyophilized plasmas were included in this trial. The mean slope of relationship between RBT/79 and CRM 149R based on the two lyophilized plasmas was the same as the corresponding slope based on fresh plasmas. Tlowever, the mean slope of relationship between RBT/79 and BCT/099 based on the two lyophilized plasmas was 4.9% higher than the mean slope based on fresh plasmas. Thus, the use of these lyophilized plasmas induced a small but significant bias in the slope of relationship between these thromboplastins of different species.


Author(s):  
Shivananda B Nayak ◽  
Dharindra Sawh ◽  
Brandon Scott ◽  
Vestra Sears ◽  
Kareshma Seebalack ◽  
...  

Purpose: i) To determine the relationship between the cardiac biomarkers ST2 and NT-proBNP with ejection fraction (EF) in heart failure (HF) patients. ii) Assess whether a superiority existed between the aforementioned cardiac markers in diagnosing the HF with reduced EF. iii) Determine the efficacy of both biomarkers in predicting a 30-day cardiovascular event and rehospitalization in patients with HF with reduced EF iv) To assess the influence of age, gender, BMI, anaemia and renal failure on the ST2 and NT-proBNP levels. Design and Methods: A prospective double-blind study was conducted to obtain data from a sample of 64 cardiology patients. A blood sample was collected to test for ST2 and NT-proBNP. An echocardiogram (to obtain EF value), electrocardiogram and questionnaire were also obtained. Results: Of the 64 patients enrolled, 59.4% of the population had an EF less than 40%. At the end of the 30- day period, 7 patients were warded, 37 were not warded, one died and 17 were non respondent. Both biomarkers were efficacious at diagnosing HF with a reduced EF. However, neither of them were efficacious in predicting 30-day rehospitalization. The mean NT-proBNP values being: not rehospitalized (2114.7486) and 30 day rehospitalization (1008.42860) and the mean ST2 values being: not rehospitalized (336.1975), and 30-day rehospitalization. (281.9657). Conclusion: Neither ST2 or NT-proBNP was efficacious in predicting the short- term prognosis in HF with reduced EF. Both however were successful at confirming the diagnosis of HF in HF patients with reduced EF.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Satoru Kanda ◽  
Takumi Hara ◽  
Ryosuke Fujino ◽  
Keiko Azuma ◽  
Hirotsugu Soga ◽  
...  

AbstractThis study aimed to investigate the relationship between autofluorescence (AF) signal measured with ultra-wide field imaging and visual functions in patients with cone-rod dystrophy (CORD). A retrospective chart review was performed for CORD patients. We performed the visual field test and fundus autofluorescence (FAF) measurement and visualized retinal structures with optical coherence tomography (OCT) on the same day. Using binarised FAF images, we identified a low FAF area ratio (LFAR: low FAF/30°). Relationships between age and logMAR visual acuity (VA), central retinal thickness (CRT), central choroidal thickness (CCT), mean deviation (MD) value, and LFAR were investigated. Thirty-seven eyes of 21 CORD patients (8 men and 13 women) were enrolled. The mean patient age was 49.8 years. LogMAR VA and MD were 0.52 ± 0.47 and − 17.91 ± 10.59 dB, respectively. There was a significant relationship between logMAR VA and MD (p = 0.001). LogMAR VA significantly correlated with CRT (p = 0.006) but not with other parameters. Conversely, univariate analysis suggested a significant relationship between MD and LFAR (p = 0.001). In the multivariate analysis, LFAR was significantly associated with MD (p = 0.002). In conclusion, it is useful to measure the low FAF area in patients with CORD. The AF measurement reflects the visual field deterioration but not VA in CORD.


2020 ◽  
pp. 088506662098250
Author(s):  
Chad M. Conner ◽  
William H. Perucki ◽  
Andre Gabriel ◽  
David M. O’Sullivan ◽  
Antonio B. Fernandez

Introduction: There is a paucity of data evaluating the impact of heart rate (HR) during Targeted Temperature Management (TTM) and neurologic outcomes. Current resuscitation guidelines do not specify a HR goal during TTM. We sought to determine the relationship between HR and neurologic outcomes in a single-center registry dataset. Methods: We retrospectively studied 432 consecutive patients who completed TTM (33°C) after cardiac arrest from 2008 to 2017. We evaluated the relationship between neurologic outcomes and HR during TTM. Pittsburgh Cerebral Performance Categories (CPC) at discharge were used to determine neurological recovery. Statistical analysis included chi square, Student’s t-test and Mann-Whitney U. A logistic regression model was created to evaluate the strength of contribution of selected variables on the outcome of interest. Results: Approximately 94,000 HR data points from 432 patients were retrospectively analyzed; the mean HR was 82.17 bpm over the duration of TTM. Favorable neurological outcomes were seen in 160 (37%) patients. The mean HR in the patients with a favorable outcome was lower than the mean HR of those with an unfavorable outcome (79.98 bpm vs 85.67 bpm p < 0.001). Patients with an average HR of 60-91 bpm were 2.4 times more likely to have a favorable neurological outcome compared to than HR’s < 60 or > 91 (odds ratio [OR] = 2.36, 95% confidence interval [CI] 1.61-3.46, p < 0.001). Specifically, mean HR’s in the 73-82 bpm range had the greatest rate of favorable outcomes (OR 3.56, 95% CI 1.95-6.50), p < 0.001. Administration of epinephrine, a history of diabetes mellitus and hypertension all were associated with worse neurological outcomes independent of HR. Conclusion: During TTM, mean HRs between 60-91 showed a positive association with favorable outcomes. It is unclear whether a specific HR should be targeted during TTM or if heart rates between 60-91 bpm might be a sign of less neurological damage.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xiaoling Zhang ◽  
Jingjing Zhang ◽  
Jiamei Li ◽  
Ya Gao ◽  
Ruohan Li ◽  
...  

AbstractEvidence indicates that glucose variation (GV) plays an important role in mortality of critically ill patients. We aimed to investigate the relationship between the coefficient of variation of 24-h venous blood glucose (24-hVBGCV) and mortality among patients with acute respiratory failure. The records of 1625 patients in the Multiparameter Intelligent Monitoring in Intensive Care II (MIMIC II) database were extracted. The 24-hVBGCV was calculated as the ratio of the standard deviation (SD) to the mean venous blood glucose level, expressed as a percentage. The outcomes included ICU mortality and in-hospital mortality. Participants were divided into three subgroups based on tertiles of 24-hVBGCV. Multivariable logistic regression models were used to evaluate the relationship between 24-hVBGCV and mortality. Sensitivity analyses were also performed in groups of patients with and without diabetes mellitus. Taking the lowest tertile as a reference, after adjustment for all the covariates, the highest tertile was significantly associated with ICU mortality [odds ratio (OR), 1.353; 95% confidence interval (CI), 1.018–1.797] and in-hospital mortality (OR, 1.319; 95% CI, 1.003–1.735), especially in the population without diabetes. The 24-hVBGCV may be associated with ICU and in-hospital mortality in patients with acute respiratory failure in the ICU, especially in those without diabetes.


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