Cancer Slope Factor and Inhalation Unit Risk for Selected Carcinogens

2009 ◽  
pp. 446-446
Keyword(s):  
Author(s):  
Brittany M. Cleary ◽  
Megan E. Romano ◽  
Celia Y. Chen ◽  
Wendy Heiger-Bernays ◽  
Kathryn A. Crawford

Abstract Purpose of Review Our comparative analysis sought to understand the factors which drive differences in fish consumption advisories across the USA — including exposure scenarios (acute and chronic health risk, non-cancer and cancer health endpoints), toxicity values (reference dose, cancer slope factor, acute tolerance level), and meal size and bodyweight assumptions. Recent Findings Fish consumption provides essential nutrients but also results in exposure to contaminants such as PCBs and methylmercury. To protect consumers from the risks of fish contaminants, fish consumption advisories are established, most often by state jurisdictions, to estimate the amount of a certain fish species a person could consume throughout their lifetime without harm. However, inconsistencies in advisories across the USA confuse consumers and undermine the public health goals of fish advisory programs. To date, no rigorous comparison of state and national fish consumption advisories has been reported. Summary Our work identifies discrepancies in key assumptions used to derive risk-based advisories between US states, reflecting differences in the interpretation of toxicity science. We also address the implications for these differences by reviewing advisories issued by contiguous states bordering two waterbodies: Lake Michigan and the Lower Mississippi River. Our findings highlight the importance of regional collaboration when issuing advisories, so that consumers of self-caught fish are equipped with clear knowledge to make decisions to protect their health.


2006 ◽  
Vol 45 (2) ◽  
pp. 159-168 ◽  
Author(s):  
A. Knafla ◽  
K.A. Phillipps ◽  
R.W. Brecher ◽  
S. Petrovic ◽  
M. Richardson
Keyword(s):  

Geosciences ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 108
Author(s):  
Jόnas Elíasson ◽  
Þorsteinn Sæmundsson

In 2014, the Varnes classification system for landslides was updated. Complex landslides can still be a problem to classify as the classification does not include the flow type in the hydrodynamical sense. Three examples of Icelandic landslides are presented and later used as case studies in order to demonstrate the methods suggested to analyze the flow. The methods are based on the different physical properties of the flow types of the slides. Three different flow types are presented, named type (i), (ii), and (iii). Types (i) and (ii) do not include turbulent flows and their flow paths are sometimes independent of the velocity. Type (iii) include high velocity flows; they are treated with the translator wave theory, where a new type of a slope factor is used. It allows the slide to stop when the slope has flattened out to the value that corresponds to the stable slope property of the flowing material. The type studies are for a fast slide of this type, also a large slip circle slide that turns into a fast-flowing slide farther down the path and finally a large slide running so fast that it can run for a kilometer on flat land where it stops with a steep front.


2003 ◽  
Vol 89 (6) ◽  
pp. 3070-3082 ◽  
Author(s):  
Jason S. Rothman ◽  
Paul B. Manis

In the ventral cochlear nucleus (VCN), neurons transform information from auditory nerve fibers into a set of parallel ascending pathways, each emphasizing different aspects of the acoustic environment. Previous studies have shown that VCN neurons differ in their intrinsic electrical properties, including the K+ currents they express. In this study, we examine these K+ currents in more detail using whole cell voltage-clamp techniques on isolated VCN cells from adult guinea pigs at 22°C. Our results show a differential expression of three distinct K+ currents. Whereas some VCN cells express only a high-threshold delayed-rectifier-like current ( IHT), others express IHT in combination with a fast inactivating current ( IA) and/or a slow-inactivating low-threshold current ( ILT). IHT, ILT, and IA, were partially blocked by 1 mM 4-aminopyridine. In contrast, only ILT was blocked by 10–100 nM dendrotoxin-I. A surprising finding was the wide range of levels of ILT, suggesting ILT is expressed as a continuum across cell types rather than modally in a particular cell type. IA, on the other hand, appears to be expressed only in cells that show little or no ILT, the Type I cells. Boltzmann analysis shows IHT activates with 164 ± 12 (SE) nS peak conductance, -14.3 ± 0.7 mV half-activation, and 7.0 ± 0.5 mV slope factor. Similar analysis shows ILT activates with 171 ± 22 nS peak conductance, -47.4 ± 1.0 mV half-activation, and 5.8 ± 0.3 mV slope factor.


Author(s):  
I Gusti Agung Lanang Widyantara ◽  
I Nyoman Merit ◽  
I Wayan Sandi Adnyana

Damage to forest resources has caused the environmental balance of watersheds (DAS) becomes damaged. It often causes the result of high levels of erosion. One of the land use changes that are currently happening is in Yeh Empas watershed. With this research can be known the proposed land use and appropriate land use planning on Yeh Empas watershed. Erosion prediction using the USLE (Universal Soil Loss Equation) method is to estimate how much the rate of erosion is happening and also to get an idea how good land management actions for the region. The proposed land use determination is using the scoring method by combining the slope factor of the field, the soil sensitivity of erosion, and the intensity of daily rainfall. Soil sampling was done by taking soil samples from a total of 11 samples of soil from the land unit. This research conducted to estimate the rate of erosion, to determines how much erosion can be tolerated in Yeh Empas watershed, and its relationship with the factors that influence it, as well as to determine the proposed of land use. The results of erosion prediction on each unit of land in the research area ranged from 1.75 to 1,254.96 tons/ha/year and has a grade level of erosion from slight to very severe. The result of tolerated erosion ranged from 15.06 to 24.32 tons/ha/year. The value of erosion prediction that exceeded from tolerated erosion value occurs on land units 7, 8, and 9. On that land units required proposed of land use and soil conservation techniques so that the value of erosion prediction could be below from tolerated erosion value. The analysis results of the proposed land use in Yeh Empas watershed, for areas inside the forest is proposed to protected forest (land units 1, 2, 3, 4, 5, and 6) and the management is by planting plants that are adapted to the contour lines of slope. In the areas outside the forest is proposed for annual crop cultivation area (land units 7, 8, and 9)the management with the farming plantation development, high density growing crops and terracing and also for crops cultivation area (land units 10 and 11) management by mulching, cover soil with high density and terracing.


2022 ◽  
Author(s):  
Sahila Beegum ◽  
P J Jainet ◽  
Dawn Emil ◽  
K P Sudheer ◽  
Saurav Das

Abstract Soil pore water pressure analysis is crucial for understanding landslide initiation and prediction. However, field-scale transient pore water pressure measurements are complex. This study investigates the integrated application of simulation models (HYDRUS-2D/3D and GeoStudio–Slope/W) to analyze pore water pressure-induced landslides. The proposed methodology is illustrated and validated using a case study (landslide in India, 2018). Model simulated pore water pressure was correlated with the stability of hillslope, and simulation results were found to be co-aligned with the actual landslide that occurred in 2018. Simulations were carried out for natural and modified hill slope geometry in the study area. The volume of water in the hill slope, temporal and spatial evolution of pore water pressure, and factor of safety were analysed. Results indicated higher stability in natural hillslope (factor of safety of 1.243) compared to modified hill slope (factor of safety of 0.946) despite a higher pore water pressure in the natural hillslope. The study demonstrates the integrated applicability of the physics-based models in analyzing the stability of hill slopes under varying pore water pressure and hill slope geometry and its accuracy in predicting future landslides.


Author(s):  
Miftahul Jannah ◽  
Amsyar Azim Ibrahim

ABSTRACT The purpose of this research was to find the vulnerability factors of flood disaster in Solok Selatan Regency. This is a descriptive exploratory research, using primary and secondary survey as methods of data collection. The primary survey was done through semi structured interview with stakeholders, selected from government group. Secondary survey was conducted by institutional survey to obtain a general description of area and flood area in Solok Selatan Regency. To know the vulnerability factors of the floods, the researcher used an analysis technique called content analysis. The result showed that the factors of flood vulnerability in Solok Selatan were: high rainfall, poor drainage condition, slope, factor of road construction vulnerable to water, many meanders, factor of total population affected by floods, siltation caused by waste. Key words : vulnerability factors, flood disaster, Solok Selatan Regency


2012 ◽  
Vol 170-173 ◽  
pp. 1238-1242
Author(s):  
Xue Wei Li ◽  
Xin Yuan ◽  
Xiao Wei Li

Abstract. Combined the strength reduction method with ABAQUS, the development of the slope plastic strain of different reduction coefficient is obtained by constantly adjusting reduction coefficient to change the strength index of the soil. The reduction coefficient is obtained from the criterion of numerical convergence and displacement mutation and plastic zone breakthrough. Through the analysis and comparison with the results, the reduction coefficient by the criterion of displacement mutation is consistent with the result of the criterion of plastic zone breakthrough. The reduction coefficient is the safety coefficient of the slope, and compared and analyzed with the slope factor of limit equilibrium method Bishop. The result shows that the displacement mutation and the plastic zone breakthrough as criterions to judge the slope instability are reasonable.


Author(s):  
Adel Bassily-Marcus ◽  
Roopa Kohli-Seth ◽  
David L. Reich

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