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Nearly all ice core archives from the Arctic and middle latitudes (such as the Alps), apart from some very high elevation sites in Greenland and the North Pacific, are strongly influenced by melting processes. The increases in the average Arctic temperature has enhanced surface snow melting even of higher elevation ice caps, especially on the Svalbard Archipelago. The increase of the frequency and altitude of winter “rain on snow” events as well as the increase of the length of the melting season have had a direct impact on the chemical composition of the seasonal and permanent snow layers due to different migration processes of water-soluble species, such as inorganic ions. This re-allocation along the snowpack of ionic species could significantly modify the original chemical signal present in the annual snow. This paper aims to give a picture of the evolution of the seasonal snow strata with a daily time resolution to better understand: a) the processes that can influence deposition b) the distribution of ions in annual snow c) the impact of the presence of liquid water on chemical re-distribution within the annual snow pack. Specifically, the chemical composition of the first 100 cm of seasonal snow on the Austre Broggerbreen Glacier (Spitsbergen, Svalbard Islands, Norway) was monitored daily from the 27th of March to the 31st of May 2015. The experimental period covered almost the entire Arctic spring until the melting season. This unique dataset gives us a daily picture of the snow pack composition, and helps us to understand the behaviour of cations (K+, Ca2+, Na+, Mg2+) and anions (Br−, I−, SO42−, NO3−, Cl−, MSA) in the Svalbard snow pack. We demonstrate that biologically related depositions occur only at the end of the snow season and that rain and melting events have different impacts on the snowpack chemistry.

The increasing prevalence of type 2 diabetes mellitus is a concern in the United States and throughout the world. Diabetes places a burden on physical and mental health as well as the economy of affected nations. Prediabetes, classified as impaired fasting blood glucose, is also on the rise, and those classified as prediabetic are at an increased risk of developing diabetes later in life. Prevention of diabetes is possible, preferable, and key in those who are prediabetic. The Diabetes Prevention Program, originally conducted in 1999, demonstrated that lifestyle changes, consisting of dietary changes and increased physical activity, was effective in preventing or delaying the onset of diabetes. However, not everyone who participates in these programs sees the same degree of success. One factor that has not been examined is to what extent quality of life plays a role in determining success in making nutritional changes and improving diet quality within a prevention program. This study analyzed potential relationships between diet quality and quality of life, as measured by the Flanagan scale. Data from 48 participants of the University of Utah’s Diabetes Prevention Program were analyzed and assessed. Anthropometric and biochemical measurements and markers were analyzed, as well as 24-hour recalls and quality of life scale scores. Diet recalls were processed through the Automated Self-Administered 24-hour Recall (ASA24) system. Diet quality was assigned by utilizing the Healthy Eating Index-2010 criteria and scores. Independent t-tests were used to assess any changes pre- and post-intervention, and linear regression was used to assess any relationship between quality of life and diet and quality of life and anthropometric measurements. Participants saw overall improvements in quality of life, weight loss, blood glucose tolerance, and a positive trend in Healthy Eating Index-2010 scores. No significant linear relationship was found between quality of life and diet quality, but significant relationships did exist for BMI, hip and waist circumferences, and oral glucose tolerance tests, indicating that a higher quality of life led to decreased values in these areas. In summary, this study shows the importance of a prevention program in increasing healthy behaviors and outcomes. Further research is necessary to track dietary changes throughout the intervention period.

Industrial electrowinning systems are by nature complex, and it can be challenging to evaluate the effects of parametric variation experimentally in production environments. Finite element simulations provide an alternative to physical experimentation. However, simulation of these systems are resource intensive and require coupled multiphysics interactions to accurately model. Despite these challenges, simulation can provide a cost effective means for improvement and optimization. To make it easier to improve operational efficiency and reducing electrowinning costs a model was developed using COMSOL Multiphysics finite element analysis (FEA) software. This work reviews the literature published on the subject providing context to the potential advances in approach. The proposed modeling strategy is presented, beginning with the Nernst--Planck equation describing the migration, convection and diffusion of ionic constituents in an electrolyte. This was coupled with a two-phase computational fluid dynamics (CFD) model to accurately describe mass transport in the system. This coupled approach will allow for accurate deposit morphology modeling. Further, roughness, operational cost and various stochastic methods will be incorporated to describe shorting and cost impact. The objective of this work is to provide a validated, more advanced model to determine the effects of operational parameters on electrowinning performance to facilitate optimization.

De laatste jaren is er in toenemende mate aandacht voor de verspreiding van bestrijdingsmiddelen via de atmosfeer. Het blijkt echter dat er vrijwel niets bekend is over de mogelijke effecten van atmosferische depositie, dit geldt in het bijzonder voor effecten op terrestrische ecosystemen. Daarom wordt in dit rapport een schatting gemaakt van deze effecten, met behulp van de thans beschikbare gegevens. Om de beschikbare data bruikbaar te maken voor dit doel was het noodzakelijk om een aantal aannamen te doen en daarom gaan de resultaten gepaard met relatief grote onzekerheden en moeten ze met enige voorzichtigheid worden gehanteerd. Met dit in het achterhoofd, wordt geconcludeerd dat het Maximum Toelaatbaar Risico (MTR) voor bodem ten gevolge van atmosferische depositie van bestrijdingsmiddelen wordt overschreden voor 3 van de 60 middelen waarvan een MTR bekend was. Het Verwaarloosbaar Risico (VR) voor bodem wordt voor 20 van deze 60 middelen overschreden. Het VR wordt voor een aantal stoffen voor alle onderzochte soortengroepen overschreden (bodemorganismen, vliegende insecten, vogels en planten). Voor deze groepen wordt het MTR in het bijzonder bij planten overschreden (voor 11 herbiciden). Verder onderzoek is noodzakelijk om de effecten te beoordelen van de overschrijding van het MTR en het VR. Over effecten van fungiciden op niet-doelwit schimmels kunnen geen uitspraken worden gedaan wegens het ontbreken van gegevens. De conclusies hebben betrekking op de middellange afstand (regio). Dichter bij de behandelde percelen kunnen hogere deposities worden verwacht. Dit is een van de onderwerpen voor nader onderzoek. Een ander belangrijk aspect dat nu nog buiten beschouwing is gelaten is de rol van transport naar en van het buitenland.

At present there is much focus on the atmospheric dispersal of pesticides. However, there is very little known about the effects of atmospheric deposition, especially in terrestrial ecosystems. In the study described here, a start has been made to clarify the possible effects on terrestrial organisms using available data. To realise this aim a number of assumptions were necessary, which lead to uncertainties in the results. Keeping this in mind, however, we could conclude that the Maximum Permissible Concentration (MPC) for soil is exceeded for 3 out of 60 compounds with a known MPC. The so-called 'Negligible Risk Level' (NRL) for soil is exceeded for 20 out of 60 compounds. The NRL is exceeded for a number of compounds for all species groups studied (soil organisms, flying insects, birds and plants). For these species groups, the MPC is exceeded especially for plants (for 11 herbicides). Further research and refinement is needed in order to assess the risks, following from the exceeding of NRL and MPC. Data are lacking though for estimating effects of fungicides on fungi. The conclusions refer to mid-range effects. Closer to the treated areas, higher depositions may be expected - one of the aspects for further research, along with the role of the transport of airborne pesticides from abroad.

Source: https://erdc-library.erdc.dren.mil/jspui/ Newburyport Harbor Model, a fixed-bed model with provisions for conversion to a movable-bed model, was constructed to scales of 1:300 horizontally and 1:100 vertically and reproduced all of Newburyport Harbor, the Merrimack River to the head of tidal influence, and a portion of the Atlantic Ocean adjacent to the harbor entrance. The model was equipped with the necessary appurtenances for accurate reproduction and measurement of tides, tidal currents, salinities, freshwater inflows, density effects, and other important prototype phenomena . Verification tests were conducted to make certain that the model hydraulic and salinity regimens agreed with those of the prototype. The agreement attained between similar model and prototype values were considered satisfactory. A second verification phase was completed and accepted in which shoaling and scour patterns in the entrance area for periods of 6 months and 1 year were simulated. The purpose of the model study was to determine the effects of proposed improvement plans on existing hydraulic, salinity, flushing, and entrance shoaling and scour conditions. Six plans were selected for extensive model testing. Test results consist of comparable measurements of tidal heights, current velocities, salinities, surface current patterns, dye dispersion, and shoaling and scouring for base and proposed improvement conditions. Analysis of these data indicates that none of the six plans would cause any significant overall effects to base condition tidal heights, salinities, or dye dispersion. The data analysis does indicate very significant changes in current patterns and magnitudes and in shoaling and scour in the entrance area and on the outer bar. Most effects were confined to the local area of the plan but generally influenced overall conditions throughout the estuary very little. Plans including the curved extension to the north jetty (Plans 3B, BE, and BX) would each result in a small reduction to the shoaling rates in the outer bar channel but would cause increased shoaling over the inner bar and seaward end of the channel to such a degree as to offset the gains realized in the outer bar channel. These three plans and Plan 2C would cause hazardous navigation conditions through the entrance due to the extremely high current velocities generated by the plans . Plans D and 3E had the least effects of any of the plans on entrance shoaling and scour. None of the six plans tested had any significant effect on shoaling and scour rates or patterns along the beaches and offshore areas. Each plan resulted in a general but small increase in shoaling along the eastern half of the north shoreline of Plum Island. Plan D provided complete protection of the north shoreline of Plum Island._x000D_ _x000D_ NOTE: This file is large. Allow your browser several minutes to download the file.