Relationship between trihalomethanes and haloacetic acids with total organic halogen during chlorination

2002 ◽  
Vol 2 (5-6) ◽  
pp. 509-514 ◽  
Author(s):  
H. Pourmoghaddas ◽  
A.A. Stevens
Keyword(s):  
Extensive Study ◽  
Haloacetic Acids ◽  
Organic Halogen ◽  
Total Organic Halogen ◽  
Chlorinated Drinking Water ◽  
Bromide Ion ◽  
Total Organic Halogens ◽  
Organic Halogens ◽  
Relationship Of ◽  
The Relationship

The effects of bromide ion, pH and reaction time on the formation of four trihalomethanes, nine haloacetic acids and total organic halogens in chlorinated drinking water have been investigated. In this extensive study, the relationship of total trihalomethanes and total haloacetic acids with total organic halogen have been evaluated. The study determined the concentration range of nine haloacetic acids and four trihalomethanes as a percentage of total organic halogen. The results showed that the percentage of total organic halogen made up of total trihalomethanes plus total haloacetic acids significantly increases with increasing bromide ion concentrations and pH. These observations suggest that both a higher bromide concentration and pH cause the formation of mainly brominated trihalomethanes with the reduction of haloacetic acids which could be identified and quantified by current USEPA methods.

scholarly journals POST DISCHARGE WALKING ACTIVITY AND 30-DAY READMISSION IN OLDER ADULTS

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S905-S905
Author(s):  
Noah Kemp ◽  
Rachel R Deer ◽  
Elena Volpi ◽  
Steve Fisher
Keyword(s):  
Older Adults ◽  
Activity Monitor ◽  
Extensive Study ◽  
Acute Illness ◽  
Post Discharge ◽  
Walking Activity ◽  
Steps Per Day ◽  
Relationship Of ◽  
The Relationship ◽  
Readmission Risk

Abstract The Centers for Medicare and Medicaid Services has determined high rates of unplanned 30-day readmission to be an indicator of substandard care. More research is needed to identify strong, objective markers of readmission risk. The purpose of this analysis was to investigate the utility of average steps per day as a biomarker in determining the 30-day readmission risk of recently discharged older adults. 133 men and women, aged 65 and older, who were capable of walking on their own, recently hospitalized with an acute illness, and discharged to home were given a StepWatch Activity Monitor and monitored for up to 30 days following discharge. Average steps per day and clinical characteristics were assessed and compared with 30-day readmission. 20 of 133 participants were readmitted within 30 days. Those who were readmitted took significantly fewer steps per day overall: 4412 vs. 5948, p=0.027, and had significantly longer stays in the hospital: 4.50 vs. 2.90 days, p=0.002. Survival analysis of our sample, grouped by tertile of mean daily steps, while not statistically significant, p=0.093, demonstrated a trend toward greater probability of readmission over the 30 days post discharge for those who were in the lowest tertile. Walking activity appears to be a moderate predictor of readmission risk. A more extensive study must be conducted to better understand the relationship of walking activity after discharge and readmission.

Some Determinants of Multidimensional Points of View: Two Studies

1970 ◽  
Vol 31 (2) ◽  
pp. 659-670 ◽  
Author(s):  
Daniel Landis ◽  
Robert M. Slivka
Keyword(s):  
Decision Making ◽  
Extensive Study ◽  
Stepwise Multiple Regression ◽  
Perceptual Style ◽  
Complex Decision Making ◽  
Complex Decision ◽  
Points Of View ◽  
Relationship Of ◽  
The Relationship ◽  
I 31

Two studies are reported bearing on the relationship of multidimensional points-of-view to cognitive perceptual style and complex decision-making performance. In Study I, 31 Ss scaled two sets of stimuli. Factor loadings from a points-of-view analysis were correlated with scores from 8 cognitive perceptual style measures. Sufficient significant correlations were found to warrant a more extensive study. In Study II, 120 Ss scaled 12 problem maps after solving the problems. Each S was also administered the measures used in Study I. The scaling data were subjected to a points-of-view analysis and related to the solution and style data by a stepwise multiple regression procedure. Results indicated that: (1) multidimensional points of view are related to style data; (2) points of view are also related to complex decision-making performance; and (3) some of the previously reported style groups break down into sub-groups.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver
Keyword(s):  
Critical Points ◽  
Scleractinian Corals ◽  
Convincing Evidence ◽  
Early Triassic ◽  
Rugose Corals ◽  
History Of ◽  
The Subject ◽  
Relationship Of ◽  
The Relationship ◽  
Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

1983 ◽  
Vol 41 ◽  
pp. 194-195
Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor
Keyword(s):  
High Resolution ◽  
Marine Invertebrates ◽  
Sea Urchins ◽  
Structural Features ◽  
Sea Stars ◽  
High Resolution Tem ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

1991 ◽  
Vol 49 ◽  
pp. 236-237
Author(s):  
J.R. Pfeiffer ◽  
J.C. Seagrave ◽  
C. Wofsy ◽  
J.M. Oliver
Keyword(s):  
Mast Cells ◽  
Protein A ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Ige Binding ◽  
Electron Imaging ◽  
Small Clusters ◽  
Relationship Of ◽  
The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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