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2.
Addict Behav ; 99: 106013, 2019 12.
Article in English | MEDLINE | ID: mdl-31430621

ABSTRACT

Whether behavioural addictions should be conceptualised using a similar framework to substance-related addictions remains a topic of considerable debate. Previous literature has developed criteria, which allows any new behavioural addiction to be considered analogous to substance-related addictions. These imply that abstinence from a related object (e.g., smartphones for heavy smartphone users) would lead to mood fluctuations alongside increased levels of anxiety and craving. In a sample of smartphone users, we measured three variables (mood, anxiety, and craving) on four occasions, which included a 24-hour period of smartphone abstinence. Only craving was affected following a short period of abstinence. The results suggest that heavy smartphone usage does not fulfil the criteria required to be considered an addiction. This may have implications for other behavioural addictions.


Subject(s)
Affect , Anxiety/psychology , Behavior, Addictive/psychology , Craving , Smartphone , Cell Phone Use , Female , Humans , Male , Young Adult
3.
J Nutr Health ; 3(2)2017.
Article in English | MEDLINE | ID: mdl-29520393

ABSTRACT

Rates of obesity are among the highest for African American adolescents in the US. However, African American adolescents benefit the least from evidence-based weight loss interventions, often experiencing poor treatment retention and low motivation. Participant evaluations provide key information for future development of family-based weight loss interventions able to address these barriers. The purpose of this study was to examine the experiences of African American adolescent and caregivers participating in the FIT Families trial for program satisfaction and content palatability. Content analysis was used to analyze semi-structured exit interviews from 136 African American adolescents [median age 14 years, 69% female] and caregiver pairs [primarily mothers] participating in a family-based 6-month behavioral weight loss intervention that was delivered either in the home or in an office setting. Participants reported most program practices [location, parent involvement, interpersonal relationship with weight loss counselors] and intervention content [cognitive behavioral skills training, motivational interviewing, contingency management] were helpful. Many adolescents [49%] and their caregivers [47%] reported that the program was acceptable overall, however noted that areas for refinement did exist. Participants reported that managing the logistics of weekly sessions was hard. Families expressed a desire for more engaging skills-based learning and the inclusion of exercise sessions and additional tailoring to needs and interests. Individualization, active learning, and support around parenting continues to be beneficial when designing interventions.

5.
BMC Psychiatry ; 8: 1, 2008 Jan 03.
Article in English | MEDLINE | ID: mdl-18173833

ABSTRACT

BACKGROUND: Studies investigating the prevalence of postnatal depression (PND) show rates ranging from 5% to 36.7%. The investigation of age, race, educational levels, religion and income as risk factors for PND has yielded conflicting results. The aim of this study is to investigate the prevalence of PND in women residing in Southern Brazil and the associated risk factors. METHODS: This is population-based cross-sectional study of women residing in Porto Alegre who delivered in June 2001. A sample of 271 participants were selected from the Record of Living Newborn Infants of the State Health Department (the official Brazilian database and stores the name and address of all women who give birth to living newborn infants) using a process based on pseudo-random numbers which choose a random sample from 2.000 records. Once the addresses were identified, the women were visited at their place of residence (home, hotel, boarding house and prison), with the interviews taking place between the 6th and the 8th week after delivery. The association between the risk factors and PND was investigated through bivariate analysis using Pearson's chi-square test. Student's t-test was used to analyze the continuous variables. To identify independent risk factors, multivariate analysis was performed using hierarchical levels with a predefined model that took into account the time relationship between PND and the risk factors. Cox's regression was used to calculate the prevalence ratios. RESULTS: The PND prevalence rate found was 20.7% (CI 95% 15.7 - 25.7). After adjusting for confounding variables, per capita income was found to have a significant association with PND. CONCLUSION: The prevalence of PND is higher than the figures found in most developed countries and similar to the figures found in developing countries. Differences in PND by regions or countries can be partially explained by the effect of income on the mediation of risk factors. In low income populations, women should be routinely evaluated for postnatal depression, and those with no partner or spouse are likely to require further care from health services and should be given the benefit of mental health prevention programs.


Subject(s)
Depression, Postpartum/epidemiology , Adolescent , Adult , Brazil/epidemiology , Catchment Area, Health , Cross-Sectional Studies , Demography , Female , Humans , Middle Aged , Pregnancy , Prevalence , Socioeconomic Factors
6.
J Phys Chem A ; 110(45): 12443-7, 2006 Nov 16.
Article in English | MEDLINE | ID: mdl-17091948

ABSTRACT

Smog chamber/FTIR techniques were used to study the atmospheric fate of n-C(x)F(2)(x)(+1)C(O) (x = 1, 2, 3, 4) radicals in 700 Torr O(2)/N(2) diluent at 298 +/- 3 K. A competition is observed between reaction with O(2) to form n-C(x)()F(2)(x)()(+1)C(O)O(2) radicals and decomposition to form n-C(x)F(2)(x)(+1) radicals and CO. In 700 Torr O(2)/N(2) diluent at 298 +/- 3 K, the rate constant ratio, k(n-C(x)F(2)(x)(+1)C(O) + O(2) --> n-C(x)F(2)(x)(+1)C(O)O(2))/k(n-C(x)F(2)(x)(+1)C(O) --> n-C(x)F(2)(x)(+1) + CO) = (1.30 +/- 0.05) x 10(-17), (1.90 +/- 0.17) x 10(-19), (5.04 +/- 0.40) x 10(-20), and (2.67 +/- 0.42) x 10(-20) cm(3) molecule(-1) for x = 1, 2, 3, 4, respectively. In one atmosphere of air at 298 K, reaction with O(2) accounts for 99%, 50%, 21%, and 12% of the loss of n-C(x)F(2)(x)(+1)C(O) radicals for x = 1, 2, 3, 4, respectively. Results are discussed with respect to the atmospheric chemistry of n-C(x)F(2)(x)(+1)C(O) radicals and their possible role in contributing to the formation of perfluorocarboxylic acids in the environment.


Subject(s)
Air Pollutants/chemistry , Aldehydes/chemistry , Atmosphere/chemistry , Carboxylic Acids/chemistry , Fluorocarbons/chemistry , Free Radicals/chemistry , Peroxides/chemistry
7.
J Phys Chem A ; 110(32): 9854-60, 2006 Aug 17.
Article in English | MEDLINE | ID: mdl-16898686

ABSTRACT

Smog chamber/Fourier transform infrared (FTIR) techniques were used to measure k(Cl+C(x)F(2x+1)CH(OH)(2)) (x = 1, 3, 4) = (5.84 +/- 0.92) x 10(-13) and k(OH+C(x)F(2x+1)CH(OH)(2)) = (1.22 +/- 0.26) x 10(-13) cm(3) molecule(-1) s(-1) in 700 Torr of N(2) or air at 296 +/- 2 K. The Cl initiated oxidation of CF(3)CH(OH)(2) in 700 Torr of air gave CF(3)COOH in a molar yield of 101 +/- 6%. IR spectra of C(x)F(2x+1)CH(OH)(2) (x = 1, 3, 4) were recorded and are presented. An upper limit of k(CF(3)CHO+H(2)O) < 2 x 10(-23) cm(3) molecule(-1) s(-1) was established for the gas-phase hydration of CF(3)CHO. Bubbling CF(3)CHO/air mixtures through liquid water led to >80% conversion of CF(3)CHO into the hydrate within the approximately 2 s taken for passage through the bubbler. These results suggest that OH radical initiated oxidation of C(x)F(2x+1)CH(OH)(2) hydrates could be a significant source of perfluorinated carboxylic acids in the environment.

8.
Environ Sci Technol ; 40(3): 864-72, 2006 Feb 01.
Article in English | MEDLINE | ID: mdl-16509330

ABSTRACT

Perfluorooctanesulfonamides [C8F17SO2N(R1)(R2)] are present in the atmosphere and may, via atmospheric transport and oxidation, contribute to perfluorocarboxylates (PFCA) and perfluorooctanesulfonate (PFOS) pollution in remote locations. Smog chamber experiments with the perfluorobutanesulfonyl analogue N-ethyl perfluorobutanesulfonamide [NEtFBSA; C4F9SO2N(H)CH2CH3] were performed to assess this possibility. By use of relative rate methods, rate constants for reactions of NEtFBSA with chlorine atoms (296 K) and OH radicals (301 K) were determined to be kCL) = (8.37 +/- 1.44) x 10(-12) and kOH = (3.74 +/- 0.77) x 10(-13) cm3 molecule(-1) s(-1), indicating OH reactions will be dominant in the troposphere. Simple modeling exercises suggestthat reaction with OH radicals will dominate removal of perfluoroalkanesulfonamides from the gas phase (wet and dry deposition will not be important) and that the atmospheric lifetime of NEtFBSA in the gas phase will be 20-50 days, thus allowing substantial long-range atmospheric transport. Liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis showed that the primary products of chlorine atom initiated oxidation were the ketone C4F9SO2N(H)COCH3; aldehyde 1, C4F9SO2N(H)CH2CHO; and a product identified as C4F9SO2N(C2H5O)- by high-resolution MS but whose structure remains tentative. Another reaction product, aldehyde 2, C4F9SO2N(H)CHO, was also observed and was presumed to be a secondary oxidation product of aldehyde 1. Perfluorobutanesulfonate was not detected above the level of the blank in any sample; however, three perfluoroalkanecarboxylates (C3F7CO2-, C2F5CO2-, and CF3CO2-) were detected in all samples. Taken together, results suggest a plausible route by which perfluorooctanesulfonamides may serve as atmospheric sources of PFCAs, including perfluorooctanoic acid.


Subject(s)
Chlorine/chemistry , Fluorocarbons/chemistry , Hydroxyl Radical/chemistry , Oxidants/chemistry , Environmental Pollutants , Kinetics , Oxidation-Reduction
9.
Environ Sci Technol ; 40(3): 924-30, 2006 Feb 01.
Article in English | MEDLINE | ID: mdl-16509338

ABSTRACT

Calculations using a three-dimensional global atmospheric chemistry model (IMPACT) indicate that n-C8F17CH2CH2OH (widely used in industrial and consumer products) degrades in the atmosphere to give perfluorooctanoic acid (PFOA) and other perfluorocarboxylic acids (PFCAs). PFOA is persistent, bioaccumulative, and potentially toxic. Molar yields of PFOA depend on location and season, are in the range of 1-10%, and are of the correct order of magnitude to explain the observed levels in Arctic fauna. Fluorotelomer alcohols such as n-C8F17CH2CH2OH appear to be a significant global source of persistent bioaccumulative perfluorocarboxylic acid pollution. This is the first modeling study of the atmospheric chemistry of a fluorotelomer alcohol.


Subject(s)
Alcohols/chemistry , Caprylates/chemistry , Fluorocarbons/chemistry , Models, Chemical , Arctic Regions , Atmosphere/chemistry , Oxidation-Reduction
10.
J Phys Chem A ; 109(43): 9816-26, 2005 Nov 03.
Article in English | MEDLINE | ID: mdl-16833295

ABSTRACT

Relative rate techniques were used to study the kinetics of the reactions of Cl atoms and OH radicals with CF(3)CH(2)C(O)H and CF(3)CH(2)CH(2)OH in 700 Torr of N(2) or air diluent at 296 +/- 2 K. The rate constants determined were k(Cl+CF(3)CH(2)C(O)H) = (1.81 +/- 0.27) x 10(-11), k(OH+CF(3)CH(2)C(O)H) = (2.57 +/- 0.44) x 10(-12), k(Cl+CF(3)CH(2)CH(2)OH) = (1.59 +/- 0.20) x 10(-11), and k(OH+CF(3)CH(2)CH(2)OH) = (6.91 +/- 0.91) x 10(-13) cm(3) molecule(-1) s(-1). Product studies of the chlorine initiated oxidation of CF(3)CH(2)CH(2)OH in the absence of NO show the sole primary product to be CF(3)CH(2)C(O)H. Product studies of the chlorine initiated oxidation of CF(3)CH(2)CH(2)OH in the presence of NO show the primary products to be CF(3)CH(2)C(O)H (81%), HC(O)OH (10%), and CF(3)C(O)H. Product studies of the chlorine initiated oxidation of CF(3)CH(2)C(O)H in the absence of NO show the primary products to be CF(3)C(O)H (76%), CF(3)CH(2)C(O)OH (14%), and CF(3)CH(2)C(O)OOH (< or =10%). As part of this work, an upper limit of k(O(3)+CF(3)CH(2)CH(2)OH) < 2 x 10(-21) cm(3) molecule(-1) s(-1) was established. Results are discussed with respect to the atmospheric chemistry of fluorinated alcohols.

11.
J Phys Chem A ; 109(9): 1849-56, 2005 Mar 10.
Article in English | MEDLINE | ID: mdl-16833516

ABSTRACT

Smog chamber/FTIR techniques were used to study the Cl atom initiated oxidation of 4:2 fluorotelomer alcohol (C(4)F(9)CH(2)CH(2)OH, 4:2 FTOH) in the presence of NO(x) in 700 Torr of N(2)/O(2) diluent at 296 K. Chemical activation effects play an important role in the atmospheric chemistry of the peroxy, and possibly the alkoxy, radicals derived from 4:2 FTOH. Cl atoms react with C(4)F(9)CH(2)CH(2)OH to give C(4)F(9)CH(2)C(*)HOH radicals which add O(2) to give chemically activated alpha-hydroxyperoxy radicals, [C(4)F(9)CH(2)C(OO(*))HOH]*. In 700 Torr of N(2)/O(2) at 296 K, approximately 50% of the [C(4)F(9)CH(2)C(OO(*))HOH]* radicals decompose "promptly" to give HO(2) radicals and C(4)F(9)CH(2)CHO, the remaining [C(4)F(9)CH(2)C(OO(*))HOH]* radicals undergo collisional deactivation to give thermalized peroxy radicals, C(4)F(9)CH(2)C(OO(*))HOH. Decomposition to HO(2) and C(4)F(9)CH(2)CHO is the dominant atmospheric fate of the thermalized peroxy radicals. In the presence of excess NO, the thermalized peroxy radicals react to give C(4)F(9)CH(2)C(O(*))HOH radicals which then decompose at a rate >2.5 x 10(6) s(-1) to give HC(O)OH and the alkyl radical C(4)F(9)CH(2)(*). The primary products of 4:2 FTOH oxidation in the presence of excess NO(x) are C(4)F(9)CH(2)CHO, C(4)F(9)CHO, and HCOOH. Secondary products include C(4)F(9)CH(2)C(O)O(2)NO(2), C(4)F(9)C(O)O(2)NO(2), and COF(2). In contrast to experiments conducted in the absence of NO(x), there was no evidence (<2% yield) for the formation of the perfluorinated acid C(4)F(9)C(O)OH. The results are discussed with regard to the atmospheric chemistry of fluorotelomer alcohols.

12.
Environ Sci Technol ; 37(17): 3816-20, 2003 Sep 01.
Article in English | MEDLINE | ID: mdl-12967100

ABSTRACT

Relative rate techniques were used to study the kinetics of the reactions of Cl atoms and OH radicals with a series of fluorotelomer alcohols, F(CF2CF2)nCH2CH2OH (n = 2, 3, 4), in 700 Torr of N2 or air, diluent at 296 +/- 2K. The length of the F(CF2CF2)n- group had no discernible impact on the reactivity of the molecule. For n = 2, 3, or 4, k(Cl + F(CF2CF2)nCH2CH2OH) = (1.61 +/- 0.49) x 10(-11) and k(OH + F(CF2CF2)nCH2CH2OH) = (1.07 +/- 0.22) x 10(-12) cm3 molecule(-1) s(-1). Consideration of the likely rates of other possible atmospheric loss mechanisms leads to the conclusion that the atmospheric lifetime of F(CF2CF2)nCH2CH2OH (n > or = 2) is determined by reaction with OH radicals and is approximately 20 d.


Subject(s)
Air Pollutants/analysis , Alkanesulfonic Acids/analysis , Fluorocarbons/analysis , Alkanesulfonic Acids/chemistry , Fluorocarbons/chemistry , Half-Life , Hydroxyl Radical/chemistry , Kinetics , Oxidants/chemistry
13.
J Am Chem Soc ; 123(38): 9299-306, 2001 Sep 26.
Article in English | MEDLINE | ID: mdl-11562212

ABSTRACT

The synthesis and examination of a novel class of reversed CPyI analogues of CC-1065 and the duocarmycins are described. Capable of a unique metal cation activation of DNA alkylation, these agents allowed the effects of the DNA binding domain (10(4)-fold increase in DNA alkylation rate and efficiency) to be partitioned into two components: that derived from enhanced DNA binding affinity and selectivity (10-80-fold) and that derived from a contribution to catalysis (250-5000-fold). In addition, the reversed enantiomeric selectivity of these sequence selective DNA alkylating agents provides further strong support for a previously disclosed model where it is the noncovalent binding selectivity of the compounds, and not the alkylation subunit or the source of catalysis, that controls the DNA alkylation selectivity.


Subject(s)
Antibiotics, Antineoplastic/chemistry , Antibiotics, Antineoplastic/pharmacology , Indoles/chemistry , Indoles/pharmacology , Pyrroles/chemistry , Pyrroles/pharmacology , Quinolones/chemistry , Quinolones/pharmacology , Alkylating Agents/chemical synthesis , Alkylating Agents/chemistry , Alkylating Agents/pharmacology , Animals , Antibiotics, Antineoplastic/chemical synthesis , Catalysis , DNA/chemistry , DNA/metabolism , Duocarmycins , Indoles/chemical synthesis , Kinetics , Leucomycins/chemistry , Leucomycins/pharmacology , Leukemia L1210/drug therapy , Pyrroles/chemical synthesis , Quinolones/chemical synthesis , Stereoisomerism
14.
Nature ; 412(6844): 321-4, 2001 Jul 19.
Article in English | MEDLINE | ID: mdl-11460160

ABSTRACT

Following the introduction of hydrochlorofluorocarbon (HCFCs) and hydrofluorocarbon (HFCs) gases as replacements for the ozone-destroying chlorofluorocarbons (CFCs), it has been discovered that HCFCs/HFCs can degrade in the atmosphere to produce trifluoroacetic acid, a compound with no known loss mechanisms in the environment, and higher concentrations in natural waters have been shown to be mildly phytotoxic. Present environmental levels of trifluooracetic acid are not accounted by HCFC/HFC degradation alone. Here we report that thermolysis of fluorinated polymers, such as the commercial polymers Teflon and Kel-F, can also produce trifluoroacetate and the similar compound chlorodifluoroacetate. This can occur either directly, or indirectly via products that are known to degrade to these haloacetates in the atmosphere. The environmental significance of these findings is confirmed by modelling, which indicates that the thermolysis of fluoropolymers in industrial and consumer high-temperature applications (ovens, non-stick cooking utensils and combustion engines) is likely to be a significant source of trifluoroacetate in urban rain water ( approximately 25 ng l-1, as estimated for Toronto). Thermolysis also leads to longer chain polyfluoro- and/or polychlorofluoro- (C3-C14) carboxylic acids which may be equally persistent. Some of these products have recently been linked with possible adverse health and environmental impacts and are being phased out of the US market. Furthermore, we detected CFCs and fluorocarbons-groups that can destroy ozone and act as greenhouse gases, respectively-among the other thermal degradation products, suggesting that continued use of fluoropolymers may also exacerbate stratospheric ozone-depletion and global warming.


Subject(s)
Acids/chemistry , Fluorocarbon Polymers/chemistry , Hydrocarbons, Halogenated/chemistry , Air Pollutants/chemistry , Ozone , Polytetrafluoroethylene/chemistry , Temperature , Trifluoroacetic Acid/chemistry
15.
Facial Plast Surg Clin North Am ; 9(3): 405-11, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11457704

ABSTRACT

There has been an explosion in the technology of injectable filler materials for soft tissue augmentation of the face in the past decade. As a result, this is an exciting field and has provided surgeons who treat the aging face with newer, minimally invasive tools and techniques to augment the soft tissues of the face. In general, there are four classes of materials available for soft-tissue augmentation: synthetic, xenogeneic, homogeneic, and autogeneic. Moreover, within each class, these materials can be further divided, according to their longevity, into permanent materials, materials that last an undefined prolonged time, and temporary fillers. These products allow the surgeon and the patient to make choices that will give the best cosmetic results.


Subject(s)
Cosmetic Techniques , Injections , Prostheses and Implants , Skin Aging , Collagen/administration & dosage , Fascia Lata/transplantation , Humans , Hyaluronic Acid/administration & dosage , Methylmethacrylate/administration & dosage
16.
Chemosphere ; 42(3): 309-18, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11100931

ABSTRACT

The environmental fate of trichloro-, dichloro-, and monochloroacetic acids, and trifluoroacetic acid was investigated using field aquatic microcosms and laboratory sediment-water systems. Trifluoroacetic acid was extremely persistent and showed no degradation during a one-year field study, though it appeared to undergo transient partitioning within an unknown pond phase as the temperature of the surroundings was reduced. Of the three chloroacetic acids, trichloro had the longest residence time (induction and decay) (approximately 40 d), dichloro the shortest (approximately 4 d), and monochloro an intermediate residence time (approximately 14 d). Laboratory studies suggest that the biodegradation of trichloro-, dichloro-, and monochloroacetic acids leads primarily to the formation of chloride and oxalic, glyoxalic, and glycolic acids, respectively.


Subject(s)
Acetates/metabolism , Trifluoroacetic Acid/metabolism , Acetates/chemistry , Biodegradation, Environmental , Dichloroacetic Acid/chemistry , Dichloroacetic Acid/metabolism , Fresh Water , Trichloroacetic Acid/chemistry , Trichloroacetic Acid/metabolism , Trifluoroacetic Acid/chemistry , Water Pollutants/metabolism
17.
Alcohol Clin Exp Res ; 24(7): 1020-7, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10924005

ABSTRACT

BACKGROUND: Research on intellectual and cognitive functioning of children of alcoholics has been marked by inconsistency, with some studies unable to document deficits. This discrepancy may reflect the substantial heterogeneity found in the alcoholic population and among families of alcoholics. The current study sought to examine the effects of familial alcoholism subtypes on intellectual, cognitive, and academic performance in early school-aged sons of alcoholics. METHODS: Subjects for the present study were 198 elementary-age boys who were participants in the larger MSU-UM Longitudinal Study. Familial alcoholism subtypes were determined based on fathers' alcoholism and antisocial personality disorder diagnoses. Intellectual functioning was measured with the Wechsler Intelligence Scale for Children-Revised (WISC-R); academic achievement was measured with the Wide Range Achievement Test-Revised. In addition, Mazes and Freedom from Distractability factor scores of the WISC-R were used to assess abstract planning and attention abilities. RESULTS: Children of antisocial alcoholics (AALs) displayed the worst IQ and academic achievement compared with children of nonantisocial alcoholics (NAALs) and controls. In addition, children of AALs displayed relatively poorer abstract planning and attention abilities compared with children from control families. Regression analyses revealed that familial alcoholism subtype continued to account for variance in child intellectual ability even when other factors were excluded. CONCLUSIONS: Findings indicate that children from AAL families are most susceptible to relative intellectual, cognitive, and academic deficits. The study further supports the proposition that familial risk characteristics (i.e., paternal alcoholism and antisociality) may serve as effective indicators of family risk for poor intellectual outcome among offspring as early as the elementary school years.


Subject(s)
Alcoholism/psychology , Cognition Disorders/psychology , Intelligence , Nuclear Family/psychology , Adult , Alcoholism/genetics , Analysis of Variance , Attention/physiology , Child , Child of Impaired Parents , Cognition Disorders/genetics , Female , Humans , Intelligence/genetics , Male , Multivariate Analysis , Prospective Studies , Regression Analysis
18.
J Otolaryngol ; 29(2): 78-82, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10819104

ABSTRACT

There are two lasers for resurfacing. The erbium:YAG laser and the CO2 laser both have different physical and physiologic differences when striking the skin. Therefore, each laser gives a different result. This article reviews the use of the Sharplan Silktouch CO2 laser for 4 years and the erbium:YAG laser for 1 year. In the last year, we have performed 40 laser procedures with the erbium:YAG laser. Discussion ensues regarding the differences and similarities of the two lasers as well as the difficulties and complications.


Subject(s)
Face/surgery , Laser Therapy/methods , Carbon Dioxide , Erbium , Humans , Plastic Surgery Procedures
19.
Anal Chem ; 72(4): 726-31, 2000 Feb 15.
Article in English | MEDLINE | ID: mdl-10701256

ABSTRACT

This investigation was carried out to evaluate 19F NMR as an analytical tool for the measurement of trifluoroacetic acid (TFA) and other fluorinated acids in the aquatic environment. A method based upon strong anionic exchange (SAX) chromatography was also optimized for the concentration of the fluoro acids prior to NMR analysis. Extraction of the analyte from the SAX column was carried out directly in the NMR solvent in the presence of the strong organic base, DBU. The method allowed the analysis of the acid without any prior cleanup steps being involved. Optimal NMR sensitivity based upon T1 relaxation times was investigated for seven fluorinated compounds in four different NMR solvents. The use of the relaxation agent chromium acetylacetonate, Cr(acac)3, within these solvent systems was also evaluated. Results show that the optimal NMR solvent differs for each fluorinated analyte. Cr(acac)3 was shown to have pronounced effects on the limits of detection of the analyte. Generally, the optimal sensitivity condition appears to be methanol-d4/2M DBU in the presence of 4 mg/mL of Cr-(acac)3. The method was validated through spike and recovery for five fluoro acids from environmentally relevant waters. Results are presented for the analysis of TFA in Toronto rainwater, which ranged from < 16 to 850 ng/L. The NMR results were confirmed by GC-MS selected-ion monitoring of the fluoroanalide derivative.


Subject(s)
Air Pollutants/analysis , Carboxylic Acids/analysis , Fresh Water/analysis , Hydrocarbons, Fluorinated/analysis , Water Pollutants, Chemical/analysis , Chromatography, Ion Exchange/methods , Fluorine , Nuclear Magnetic Resonance, Biomolecular/methods , Rain , Trifluoroacetic Acid/analysis
20.
J Otolaryngol ; 29(6): 377-81, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11770147

ABSTRACT

OBJECTIVE: To determine patient satisfaction with the postoperative recovery period and surgical outcome after facial laser resurfacing. DESIGN: Survey. PATIENTS: Patients who underwent facial laser resurfacing by two of the authors (PAA or DAFE) between 1995 and 1996. Questionnaires were completed by 47 of 100 patients. INTERVENTIONS: Facial laser resurfacing with the Sharplan CO2 laser and SilkTouch Scanner. MAIN OUTCOME MEASURES: Questionnaire. Statistical analysis was generated from a 5-point analogue scale. RESULTS: The overall side effects were moderate in severity, were well tolerated, and met the expectations of our patients. Redness was the most frequent side effect with an average duration of 3 months. Most patients returned to occupational and social activities at 2.5 weeks. Moderate lifestyle disruption was more frequent after full-face laser resurfacing than partial-face laser resurfacing. Excellent improvement was achieved for removal of fine wrinkles, improvement of skin quality, and sun-damaged skin. Good improvement was obtained for acne scarring and deep rhytids. Overall goals were attained in 89% of patients. CONCLUSIONS: Laser resurfacing produced excellent results for fine rhytids, skin quality, and sun-damaged skin. Return to social and occupational activities may occur early in recovery with the use of camouflage make-up. Patient education and close follow-up are necessary in the postoperative period.


Subject(s)
Face/surgery , Laser Therapy/methods , Adult , Aged , Convalescence , Female , Humans , Male , Middle Aged , Postoperative Complications/diagnosis , Postoperative Complications/epidemiology , Severity of Illness Index , Surveys and Questionnaires , Treatment Outcome
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