the answer is 21<span>% oxygen, </span>
Answer:
Hepato- and nephrotoxicity of fluoride have been demonstrated in animals, but few studies have examined potential effects in humans. This population-based study examines the relationship between chronic low-level fluoride exposure and kidney and liver function among United States (U.S.) adolescents. This study aimed to evaluate whether greater fluoride exposure is associated with altered kidney and liver parameters among U.S. youth.
This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (2013–2016). We analyzed data from 1983 and 1742 adolescents who had plasma and water fluoride measures respectively and did not have kidney disease. Fluoride was measured in plasma and household tap water. Kidney parameters included estimated glomerular filtration rate (calculated by the original Schwartz formula), serum uric acid, and the urinary albumin to creatinine ratio. Liver parameters were assessed in serum and included alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, blood urea nitrogen, gamma-glutamyl transferase, and albumin. Survey-weighted linear regression examined relationships between fluoride exposure and kidney and liver parameters after covariate adjustment. A Holm-Bonferroni correction accounted for multiple comparisons.
The average age of adolescents was 15.4 years. Median water and plasma fluoride concentrations were 0.48 mg/L and 0.33 μmol/L respectively. A 1 μmol/L increase in plasma fluoride was associated with a 10.36 mL/min/1.73 m2 lower estimated glomerular filtration rate (95% CI: −17.50, −3.22; p = 0.05), a 0.29 mg/dL higher serum uric acid concentration (95% CI: 0.09, 0.50; p = 0.05), and a 1.29 mg/dL lower blood urea nitrogen concentration (95%CI: −1.87, −0.70; p < 0.001). A 1 mg/L increase in water fluoride was associated with a 0.93 mg/dL lower blood urea nitrogen concentration (95% CI: −1.44, −0.42; p = 0.007).
Fluoride exposure may contribute to complex changes in kidney and liver related parameters among U.S. adolescents. As the study is cross-sectional, reverse causality cannot be ruled out; therefore, altered kidney and/or liver function may impact bodily fluoride absorption and metabolic processes.
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Answer:
Solidifications of molten materials.
Answer:
5.) The possible genotypes should be: RR RB BB ( if the could for the same proteins)
6.) Frequency of R: 0.5
7.)Frequency of R: 0.5
8.)Frequency of R: 0.375
Explanation:
5.) If R and B code for the different forms of the same protein then they are only a few possible out comes
6.) First calculate the total alleles in population
allele R= 40
Allele B=40
total allele = R+B= 40+40
=80
Now to find allele R frequency is:
(Total R alleles) / (Total allele in pop)
40/80=
0.5
7.)Calculate the total alleles
Alleles from for R
RR= 10
R=10x 2= 20
Multiply the value by 2 because there are 2 R alleles present in
RB=20
R=20
Number doesn't change there is only 1 R allele
Total R=20+20
=40
Alleles For B
BB=10
B=10×2
=20
Same thing here, two B alleles together so multiple by 2
RB=20
B=20
Total B= 20+20
=40
Total alleles in pop add
40+40
=80
Frequency of R
Total of R/Total Alleles
=40/80
=0.5
8.)Repeat the same thing in 7 but use different numbers
RR=10
R=10x2
=20
RB=10
R=10
Total R= 20+10
=30
<span>D. Gravity is the force of attraction between two objects and is dependent upon the mass of the objects and the distance between the objects.</span>
