scholarly journals Caries affected by calcium and fluoride in drinking water and family income

2017 ◽  
Vol 16 (1) ◽  
pp. 49-56
Author(s):  
Erik Arvin ◽  
Allan Bardow ◽  
Henrik Spliid
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Linear Model ◽  
Family Income ◽  
General Linear Model ◽  
Relative Importance ◽  
Water Softening ◽  
Independent Variables ◽  
Independent Effects ◽  
The Relationship

Abstract Water quality and socioeconomics influence caries in populations. This study broadens previous studies on how caries is associated with fluoride and calcium in drinking water and with family income by quantifying the combined effect of the three independent variables. The effects of calcium and fluoride can be described as independent effects of the two ions or, alternatively, in the form of saturation with respect to fluorite (CaF2). A general linear model describes this relationship with high significance and the model confirms the important protective effect of calcium and fluoride, independently against caries. From the model, the relative importance of fluoride and calcium to protect against caries is quantified. The relationship between caries and family income is also highly significant. It is illustrated how the linear model can be applied in planning and analyzing drinking water softening in relation to caries.

Perceptions of Water Quality in First Nations Communities: Exploring the Role of Context

2015 ◽  
Vol 10 (2) ◽  
pp. 225-249 ◽  
Author(s):  
Julia Baird ◽  
Ryan Plummer ◽  
Diane Dupont ◽  
Blair Carter
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Social Context ◽  
First Nations ◽  
Water Governance ◽  
Social Contexts ◽  
Adaptive Governance ◽  
The Social ◽  
The Relationship

Drinking water quality problems are persistent and challenging for many of Canada's First Nations communities despite past and ongoing initiatives to improve the situation. These initiatives have often been employed without consideration for understanding the social context that is so critical for the development of appropriate water governance approaches. This article offers insights about the relationship between institutions for water governance and perceptions in three Ontario First Nations communities. Similarities among communities were particularly noticeable for gender where women valued water more highly and were less content with water quality. The findings presented here highlight potential impacts of displacement, gender, and water sources on perceptions of water quality and offer initial insights that indicate the need for further research to consider the potential for adaptive governance approaches that enhance fit between problem and social contexts.

A Definition of Suppression Situations for the General Linear Model: A Regression Weights Approach

1985 ◽  
Vol 45 (2) ◽  
pp. 281-284 ◽  
Author(s):  
Joseph Tzelgov ◽  
Avishai Henik
Keyword(s):  
Linear Combination ◽  
Linear Model ◽  
General Linear Model ◽  
General Linear ◽  
Independent Variables ◽  
Definition Of

Holling (1983) suggested a definition of suppression in terms of the relations between the independent variables (predictors) and the linear combination for predicting the dependent variable (criterion). However, Holling's definition includes only a subset of Conger's absolute suppression situations. The present work suggests a definition of suppression situations that is in line with Holling's ideas and with Conger's definition of suppression.

scholarly journals The ADAMTS9 gene is associated with mandibular retrusion in a Chinese population

2020 ◽  
Author(s):  
Ying Cai ◽  
Zhenyu Ni ◽  
Weiting Chen ◽  
Yu Zhou
Keyword(s):  
Linear Model ◽  
Multifactor Dimensionality Reduction ◽  
General Linear Model ◽  
General Linear ◽  
Nucleotide Polymorphisms ◽  
Bonferroni Correction ◽  
Single Nucleotide ◽  
Significance Level ◽  
Mandibular Retrusion ◽  
The Relationship

Abstract Background: Many studies suggest that genetics plays an important role in mandibular retrusion. In this study, we hypothesized that single nucleotide polymorphisms (SNPs) of ADAMTS9 gene is associated with mandibular retrusion in a Han Chinese population.Methods: Saliva samples from 60 patients undergoing orthodontic for correction of malocclusion were collected. 130 SNPs genotyping of ADAMTS9 was used to asses the association of polymorphisms with the mandibular retrusion. The general linear model using age,gender and ANB as covariates weighed the relationship between SNP and mandibular retrusion. Additionally we leveraged the generalized multifactor dimensionality reduction (GMDR) method to investigate SNP-SNP interactions. The significance level was set at P < 0.05 in this study.Results: The general linear model results showed that four SNPs (rs1014640,rs7648540,rs75839462 and rs4605539 ) in the ADAMTS9 gene may be related to the occurrence of mandibular retrusion,even after Bonferroni correction. In addition, we further found that the interaction between the ADAMTS9 rs75839462 and ADAMTS9 rs80118777 promoted the occurrence of mandibular retrusion.Conclusion: Our finding suggest that the ADAMTS9 gene may cause mandibular retrsusion independently and through SNP-SNP interactions.

scholarly journals Centralized softening as a solution to chloride pollution: An empirical analysis based on Minnesota cities

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246688
Author(s):  
Baishali Bakshi ◽  
Elise M. Doucette ◽  
Scott J. Kyser
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Municipal Wastewater ◽  
Cost Ratio ◽  
Effective Solution ◽  
Water Softening ◽  
Aquatic Life ◽  
Home Based ◽  
Water Plants ◽  
Chloride Treatment

Chloride is a key component of salt, used in many activities such as alkali production, water treatment, and de-icing. Chloride entering surface and groundwater is a concern due to its toxicity to aquatic life and potential to degrade drinking water sources. Minnesota being a hard-water state, has a high demand for water softening. Recent research has found that home-based water softeners contribute significantly to chloride loading at municipal wastewater treatment plants (WWTPs). Because of this, many WWTPs would now require water quality based effluent limits (WQBELs) to comply with the state’s chloride water quality standards (WQS), unless they install chloride treatment technologies, which are limited and cost-prohibitive to most communities. A potential solution to this problem, is shifting from home-based water softening to a system where water is softened at drinking water plants, before reaching homes, i.e. centralized softening, analyzed in this paper based on its ability to address both chloride pollution and water softening needs, at reasonable cost. We estimate lifetime costs of three alternative solutions: centralized softening, home-based softening, and a Business as Usual (BAU) or baseline alternative, using annualized 20-year loan payments and Net Present Value (NPV), applied to 84 Minnesota cities with matching data on drinking water plants and WWTPs. We find that centralized softening using either Reverse Osmosis (RO) or lime-softening technologies is the more cost-effective solution, compared to the alternative of home-based softening with end-of-pipe chloride treatment, with a cost ratio in the range 1:3–1:4. Between the two centralized softening options, we find RO-softening to be the lower cost option, only slightly more costly (1.1 cost ratio) than the BAU option. Considering additional environmental and public health benefits, and cost savings associated with removal of home-based softeners, our results provide helpful information to multiple stakeholders interested in an effective solution to chloride pollution.

scholarly journals Farmers’ Perception of Environmental Degradation Due to Use of Pesticides

2015 ◽  
Vol 6 (2) ◽  
pp. 13-18
Author(s):  
S Akter ◽  
MA Miah ◽  
MZ Rhaman ◽  
MS Hossen ◽  
MA Baten
Keyword(s):  
Environmental Degradation ◽  
Family Income ◽  
Media Exposure ◽  
Environmental Knowledge ◽  
Farm Size ◽  
Independent Variables ◽  
Organizational Participation ◽  
High Knowledge ◽  
Independent Variable ◽  
The Relationship

The study was conducted mainly to have an understanding about the farmers’ perception of environmental degradation due to use of pesticides. Data for the study were collected by personal interviewing from 69 randomly selected farmers of Kabaria kanda village of sadar upazila of Mymensingh district during the period of 01 November to 15 November, 2012. Pearson’s product moment correlation co-efficient were computed to examine the relationship between the concerned variables. Perception on environmental degradation was reflected more in the young (30.4 percent) to middle age (42 percent) group compared to old age group. Majority (72.5 percent) of the farmers in the study area were found to have no organizational participation. The highest proportion (73.9 percent) of the respondents fell in the moderate knowledge category while none fell in less knowledge and 26.1 percent in the high knowledge category respectively. Only 1.4 percent of the farmers had moderately perception on environmental knowledge as compared to 98.6 percent favorable perception. Out of eight independent variables, five of them, i.e. years of schooling, farm size, annual family income, media exposure and knowledge on the use of agro-chemicals had positive relationships with their perception of environmental degradation due use of pesticides. Only three independent variable i.e. age, household size and organizational participation had no relationship with their perception of environmental degradation due use of pesticides.DOI: http://dx.doi.org/10.3329/jesnr.v6i2.22079 J. Environ. Sci. & Natural Resources, 6(2): 13-18 2013

scholarly journals Evaluation and comparison of centralized drinking water softening technologies: Effects on water quality indicators

2021 ◽  
pp. 117439
Author(s):  
Camilla Tang ◽  
Martin Rygaard ◽  
Per S. Rosshaug ◽  
John B. Kristensen ◽  
Hans-Jørgen Albrechtsen
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Quality Indicators ◽  
Water Softening ◽  
Water Quality Indicators
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