scholarly journals Establishment of Geochemical Thresholds for Vanadium Throughout Korea and at Potential Development Sites Using Geochemical Map Data

Author(s):  
Joo Sung Ahn ◽  
Seung-Jun Youm ◽  
Yong-Chan Cho ◽  
Gil-Jae Yim ◽  
Sang-Woo Ji

Abstract Geochemical maps can be used for a variety of purposes, one of which is to establish regional or local geochemical thresholds for the analyzed elements. In the case of vanadium, as industrial demand and use increases, it is necessary to expand the development of vanadium in Korea. However, the environmental management standards are insufficient. Therefore, in this study, using geochemical data, we derived geochemical threshold values for the entire country and areas with potential for the development of vanadium deposits. The regional (country-wide) threshold value was derived using logarithmic transformation of raw data (N = 23,548) of the first- and second-order stream sediments collected across the country in the late 1990s and the early 2000s. The median + 2 median absolute deviation (MAD) and Tukey inner fence (TIF) values were 116 mg/kg and 200 mg/kg, respectively. Of these, the TIF standard, which showed 0.6% of data exceeding the threshold, was judged to be appropriate for distinguishing clear enrichment or contamination of vanadium. In the case of the Geumsan and Pocheon, areas with potential for vanadium development, the TIF and median + 2 MAD values of 259 mg/kg and 218 mg/kg, respectively, can be used as the criteria for evaluating the impact of environmental pollution before and after deposit development. Likewise, by deriving threshold values of the target elements using geochemical map data, it is possible to provide basic environmental information for geochemical evaluation and follow-up management in advance during large-scale site development.

2021 ◽  
pp. 009539972110642
Author(s):  
Trine H. Fjendbo ◽  
Christian B. Jacobsen ◽  
Seung-Ho An

Leadership training is key to promoting more active leadership, but the effects of leadership training can depend on the gender context. Gender congruence between manager and employee can affect how the manager employs leadership behaviors adapted from training and how employees perceive leadership behavior. Quantitative data on 474 managers’ 4,833 employees before and after a large-scale field experiment with leadership training enable us to examine changes in employee-perceived leadership following training. The results show that gender congruence between manager and employee is associated with stronger leadership training effects on employee-perceived leadership behaviors. Female gender congruence shows the most pronounced effects.


2020 ◽  
Author(s):  
Brett R. Bayles ◽  
Michaela F George ◽  
Haylea Hannah ◽  
Patti Culross ◽  
Rochelle R. Ereman ◽  
...  

Background: The first shelter-in-place (SIP) order in the United States was issued across six counties in the San Francisco Bay Area to reduce the impact of COVID-19 on critical care resources. We sought to assess the impact of this large-scale intervention on emergency departments (ED) in Marin County, California. Methods: We conducted a retrospective descriptive and trend analysis of all ED visits in Marin County, California from January 1, 2018 to May 4, 2020 to quantify the temporal dynamics of ED utilization before and after the March 17, 2020 SIP order. Results: The average number of ED visits per day decreased by 52.3% following the SIP order compared to corresponding time periods in 2018 and 2019. Both respiratory and non-respiratory visits declined, but this negative trend was most pronounced for non-respiratory admissions. Conclusions: The first SIP order to be issued in the United States in response to COVID-19 was associated with a significant reduction in ED utilization in Marin County.


2006 ◽  
Vol 24 (8) ◽  
pp. 2075-2089 ◽  
Author(s):  
A. Chakraborty ◽  
R. S. Nanjundiah ◽  
J. Srinivasan

Abstract. A theory is proposed to determine the onset of the Indian Summer Monsoon (ISM) in an Atmospheric General Circulation Model (AGCM). The onset of ISM is delayed substantially in the absence of global orography. The impact of orography over different parts of the Earth on the onset of ISM has also been investigated using five additional perturbed simulations. The large difference in the date of onset of ISM in these simulations has been explained by a new theory based on the Surface Moist Static Energy (SMSE) and vertical velocity at the mid-troposphere. It is found that onset occurs only after SMSE crosses a threshold value and the large-scale vertical motion in the middle troposphere becomes upward. This study shows that both dynamics and thermodynamics play profound roles in the onset of the monsoon.


2019 ◽  
Vol 111 ◽  
pp. 03010
Author(s):  
Imrich Sánka ◽  
Dušan Petráš

This article investigates the impact of energy renovation on the indoor environmental quality of apartment building during heating season. The study was performed in one residential building before and after its renovation. Energy auditing and classification of the selected building into energy classes were carried out. Additionally, evaluation of indoor air quality was performed using objective measurements and subjective survey. Thermal environment and concentration of CO2 was measured in bedrooms. Higher concentrations of CO2 was observed in the residential building after its renovation. The concentrations of CO2, in some cases exceeded the recommended maximum limits, especially after implementing of energy saving measures on the building. The average air exchange rate was visible higher before renovation of the building. The current study indicates that large-scale of renovations may reduce the quality of the indoor environment in many apartments, especially in the winter season.


2006 ◽  
Vol 3 (3) ◽  
pp. 357-369 ◽  
Author(s):  
K. K. Yates ◽  
R. B. Halley

Abstract. The severity of the impact of elevated atmospheric pCO2 to coral reef ecosystems depends, in part, on how seawater pCO2 affects the balance between calcification and dissolution of carbonate sediments. Presently, there are insufficient published data that relate concentrations of pCO2 and CO32− to in situ rates of reef calcification in natural settings to accurately predict the impact of elevated atmospheric pCO2 on calcification and dissolution processes. Rates of net calcification and dissolution, CO32− concentrations, and pCO2 were measured, in situ, on patch reefs, bare sand, and coral rubble on the Molokai reef flat in Hawaii. Rates of calcification ranged from 0.03 to 2.30 mmol CaCO3 m−2 h−1 and dissolution ranged from –0.05 to –3.3 mmol CaCO3 m−2 h−1. Calcification and dissolution varied diurnally with net calcification primarily occurring during the day and net dissolution occurring at night. These data were used to calculate threshold values for pCO2 and CO32− at which rates of calcification and dissolution are equivalent. Results indicate that calcification and dissolution are linearly correlated with both CO32− and pCO2. Threshold pCO2 and CO32− values for individual substrate types showed considerable variation. The average pCO2 threshold value for all substrate types was 654±195 μatm and ranged from 467 to 1003 μatm. The average CO32− threshold value was 152±24 μmol kg−1, ranging from 113 to 184 μmol kg−1. Ambient seawater measurements of pCO2 and CO32− indicate that CO32− and pCO2 threshold values for all substrate types were both exceeded, simultaneously, 13% of the time at present day atmospheric pCO2 concentrations. It is predicted that atmospheric pCO2 will exceed the average pCO2 threshold value for calcification and dissolution on the Molokai reef flat by the year 2100.


2020 ◽  
Vol 30 (1) ◽  
pp. 98-102 ◽  
Author(s):  
Rebecca Glover-Kudon ◽  
Doris G Gammon ◽  
Todd Rogers ◽  
Ellen M Coats ◽  
Brett Loomis ◽  
...  

IntroductionOn 1 January 2016, Hawaii raised the minimum legal age for tobacco access from 18 to 21 years (‘Tobacco 21 (T21)’) statewide, with no special population exemptions. We assessed the impact of Hawaii’s T21 policy on sales of cigarettes and large cigars/cigarillos in civilian food stores, including menthol/flavoured product sales share.MethodsCigarette and large cigar/cigarillo sales and menthol/flavoured sales share were assessed in Hawaii, California (implemented T21 in June 2016 with a military exemption), and the US mainland using the only Nielsen data consistently available for each geographical area. Approximate monthly sales data from large-scale food stores with sales greater than US$2 million/year covered June 2012 to February 2017. Segmented regression analyses estimated changes in sales from prepolicy to postpolicy implementation periods.ResultsFollowing T21 in Hawaii, average monthly cigarette unit sales dropped significantly (−4.4%, p<0.01) coupled with a significant decrease in menthol market share (−0.8, p<0.01). This combination of effects was not observed in comparison areas. Unit sales of large cigars/cigarillos decreased significantly in each region following T21 implementation. T21 policies in Hawaii and California showed no association with flavoured/menthol cigar sales share, but there was a significant increase in flavoured/menthol cigar sales share in the USA (7.1%, p<0.01) relative to Hawaii’s implementation date, suggesting T21 may have attenuated an otherwise upward trend.ConclusionsAs part of a comprehensive approach to prevent or delay tobacco use initiation, T21 laws may help to reduce sales of cigarette and large cigar products most preferred by US youth and young adults.


2013 ◽  
Vol 6 (1) ◽  
pp. 23-42 ◽  
Author(s):  
Diana Deek ◽  
Penny Werthner ◽  
Kyle J. Paquette ◽  
Diane Culver

This study examines the impact of a coach education program on coach learning and perceived changes to coaching practices, while situating this episodic learning experience within a lifelong-learning perspective. Three sets of in-depth interviews were conducted with 10 coaches taking part in one of three competition-development modules within Canada’s National Coaching Certification Program (Coaching and Leading Effectively, Managing Conflict, and Psychology of Performance). It was found that (a) the coaches’ biographies varied widely, (b) all of the coaches reported learning from the modules, (c) eight of ten coaches reported a change in their coaching practices as a result of participation in one of the modules, and (d) the coaches credited a combination of mediated, unmediated, and internal learning situations for their learning before and after the modules. These findings suggest that a large-scale coach education program can have an impact on coaches when the program takes a lifelong-learning perspective and integrates constructivist principles into its design and delivery.


2021 ◽  
pp. 336-341
Author(s):  
Medkova ◽  
Krasovskaya

In the conditions of the Shirinsky District, monitoring was carried out for the first time for the change in number of helminthic diseases before and after fires. Fires have led to changes in the properties of the ground cover, soil, and simplification of communities; the complex of soil-dwelling arthropods has undergone a number of significant changes, which are manifested in a decrease in number and species diversity. The aim of the study is to determine the prevalence of various parasites in farm animals after large-scale fires on the example of the Shirinsky District of the Republic of Khakassia. The study subject was eggs, larvae and helminths of the studied animals. The study object was farm animals. The studies were carried out by the method of sequential washing of fecal samples. Based on the study results of 786 fecal samples from various animals, we received the following results. We have proved that the fire had a great impact on the parasitofauna of animals in the Shirinsky District; the number of invasive diseases first decreased after fires and then increased again. We found out that the decrease in number of parasitic diseases was associated with the following: fires had an adverse effect on the ecological state of the environment and changed the existence conditions of living organisms. The fire destroyed eggs, larvae and definitive hosts of the parasites.


2021 ◽  
Author(s):  
Marina A Pak ◽  
Karina A Markhieva ◽  
Mariia S Novikova ◽  
Dmitry S Petrov ◽  
Ilya S Vorobyev ◽  
...  

AlphaFold changed the field of structural biology by achieving three-dimensional (3D) structure prediction from protein sequence at experimental quality. The astounding success even led to claims that the protein folding problem is "solved". However, protein folding problem is more than just structure prediction from sequence. Presently, it is unknown if the AlphaFold-triggered revolution could help to solve other problems related to protein folding. Here we assay the ability of AlphaFold to predict the impact of single mutations on protein stability (ΔΔG) and function. To study the question we extracted metrics from AlphaFold predictions before and after single mutation in a protein and correlated the predicted change with the experimentally known ΔΔG values. Additionally, we correlated the AlphaFold predictions on the impact of a single mutation on structure with a large scale dataset of single mutations in GFP with the experimentally assayed levels of fluorescence. We found a very weak or no correlation between AlphaFold output metrics and change of protein stability or fluorescence. Our results imply that AlphaFold cannot be immediately applied to other problems or applications in protein folding.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Cai Shukai ◽  
Wang Haochen ◽  
Zhou Xiaohong

This paper proposed a substantial gap to a large-scale population density and city size on regional innovation output. To measure the impact of population density and city size on regional innovation output, this study employs the threshold effect model with panel data of 230 prefectures and cities from 2007 to 2016. Based on the econometric analysis, the results exhibit a positive and significant relationship between population density, city size, and innovation output. This correlation suggests that when one factor increases, the other increases in the parallel direction and vice versa. Moreover, when the city size expands the threshold value of 2.934 percent, the innovation promotes and increases the effects of urban-scale expansion. On the other hand, for medium- and low-density cities, the increase of urban population density has a significant and positive impact on urban innovation output. However, for high-density cities, the increase of population density has no significant impact on innovation output.


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