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671.

Background

Tobacco users receiving behavioural and pharmacological assistance are more likely to quit. Although telephone quitlines provide population access to counselling, few offer pharmacotherapy.

Objective

To assess change in cessation rates and programme impact after the addition of free nicotine replacement therapy (NRT) to statewide quitline services.

Design, setting, participants

An observational study of cohorts of callers to the Minnesota QUITPLANSM Helpline before (n  =  380) and after (n  =  373) the addition of access to free NRT.

Intervention

Mailing of NRT (patch or gum) to callers enrolling in multi‐session counselling.

Main outcome measure

Thirty‐day abstinence six months after programme registration.

Results

The number of callers increased from 155 (SD 75) to 679 (180) per month pre‐NRT to post‐NRT (difference 524, 95% confidence interval (CI) 323 to 725). Post‐NRT, the proportion of callers enrolling in multi‐session counselling (23.4% v 90.1%, difference 66.6%, 95% CI 60.8% to 71.6%) and using pharmacotherapy (46.8% v 86.8%, difference 40.0%, 95% CI 31.3% to 47.9%) increased. Thirty‐day abstinence at six months increased from 10.0% pre‐NRT to 18.2% post‐NRT (difference 8.2%, 95% CI 3.1% to 13.4%). Post‐NRT the average number of new ex‐smokers per month among registrants increased from 15.5 to 123.6 (difference 108.1, 95% CI 61.1 to 155.0). The cost per quit pre‐NRT was $1362 (SD $207). The cost per quit post‐NRT was $1934 ($215) suggesting a possible increase in cost per quit (difference $572, 95% CI −$12 to $1157).

Conclusion

The addition of free NRT to a state quitline is followed by increases in participation and abstinence rates resulting in an eightfold increase in programme impact. These findings support the addition of access to pharmacological therapy as part of state quitline services.  相似文献   
672.
Antimony is an element of growing interest for a variety of industrial applications, even though Sb compounds are classified as priority pollutants by the Environmental Protection Agency of the United States. Iron (Fe) hydroxides appear to be important sorbents for Sb in soils and sediments, but mineral surfaces can also catalyze oxidation processes and may thus mobilize Sb. The aim of this study was to investigate whether goethite immobilizes Sb by sorption or whether Sb(III) adsorbed on goethite is oxidized and then released. The sorption of both Sb(III) and Sb(V) on goethite was studied in 0.01 and 0.1 M KClO4 M solutions as a function of pH and Sb concentration. To monitor oxidation processes Sb species were measured in solution and in the solid phase. The results show that both Sb(III) and Sb(V) form inner-sphere surface complexes at the goethite surface. Antimony(III) strongly adsorbs on goethite over a wide pH range (3-12), whereas maximum Sb(V) adsorption is found below pH 7. At higher ionic strength, the desorption of Sb(V) is shifted to lower pH values, most likely due to the formation of ion pairs KSb(OH)6 degrees. The sorption data of Sb(V) can be fitted by the modified triple-layer surface complexation model. Within 7 days, Sb(III) adsorbed on goethite is partly oxidized at pH 3, 5.9 and 9.7. The weak pH-dependence of the rate coefficients suggests that adsorbed Sb(III) is oxidized by 02 and that the coordination of Sb(III) to the surface increases the electron density of the Sb atom, which enhances the oxidation process. At pH values below pH 7, the oxidation of Sb(III) did not mobilize Sb within 35 days, while 30% of adsorbed Sb(III) was released into the solution at pH 9.9 within the same time. The adsorption of Sb(III) on Fe hydroxides over a wide pH range may be a major pathway for the oxidation and release of Sb(V).  相似文献   
673.
Semiconductor quantum dots (QDs) have been widely used for fluorescent labelling. However, their ability to transfer electrons and holes to biomolecules leads to spectral changes and effects on living systems that have yet to be exploited. Here we report the first cell-based biosensor based on electron transfer between a small molecule (the neurotransmitter dopamine) and CdSe/ZnS QDs. QD-dopamine conjugates label living cells in a redox-sensitive pattern: under reducing conditions, fluorescence is only seen in the cell periphery and lysosomes. As the cell becomes more oxidizing, QD labelling appears in the perinuclear region, including in or on mitochondria. With the most-oxidizing cellular conditions, QD labelling throughout the cell is seen. Phototoxicity results from the creation of singlet oxygen, and can be reduced with antioxidants. This work suggests methods for the creation of phototoxic drugs and for redox-specific fluorescent labelling that are generalizable to any QD conjugated to an electron donor.  相似文献   
674.
Isotopic techniques have become a valuable tool for assessing the lability or potential availability of elements in soil. Until now, work on soil Cu has been limited to E-value methods where soil solution extracts are obtained by physical means due to the very short (12.4 h) half-life of the radio isotope 64Cu. However, a stable isotope method has recently been developed for determining soil Cu E values that utilizes enhancement of the 65Cu isotope in soil and measurement of the subsequent ratio with 63Cu. We have developed an L-value technique for soil Cu, where plants are used to sample the soil solution and therefore give a direct measure of the plant available Cu. The L-value technique developed was then compared, and found to be equivalent, with E values using equilibration periods up to and including the growth period of plants in the L-value method.  相似文献   
675.
A 5′ nuclease duplex real-time polymerase chain reaction (PCR) assay was developed and validated with various food products for the specific and fast detection of Salmonella spp. in food. The assay used previously published primers in combination with a newly developed probe targeting the invA gene. An internal amplification control, which is coamplified in a duplex PCR, was included in the assay. The analysis of 1,934 natural food samples with real-time PCR and the cultural method in parallel resulted in a relative accuracy of 100% and 99.84% respectively, depending on the enrichment procedure in which buffered peptone water and selective enrichment in Rappaport–Vassiliadis (RV) broth were employed. The duplex real-time PCR assay has proven to be a specific, sensitive and fast screening method for Salmonella spp. in food. The overall analysis time of the PCR method was approximately 28 h, in contrast to 4 to 5 days with conventional Salmonella diagnostics. The developed assay has been shown to be a reliable diagnostic tool for use in routine analysis. It has been validated thoroughly and has become an official method in Germany for the detection of Salmonella spp. in food.  相似文献   
676.
Knowledge of trace metal speciation in soil pore waters is important in addressing metal bioavailability and risk assessment of contaminated soils. Numerous analytical methods have been utilized for determining trace metal speciation in aqueous environmental matrixes; however, most of these methods suffer from significant interferences. The Donnan dialysis membrane technique minimizes these interferences and has been used in this study to determine free Zn2+, Cd2+, Cu2+, and Pb2+ activities in pore waters from 15 agricultural and 12 long-term contaminated soils. The soils vary widely in their origin, pH, organic carbon content, and total metal concentrations. Pore water pM2+ activities also covered a wide range and were controlled by soil pH and total metal concentrations. For the agricultural soils, most of the free metal activities were below detection limit, apart from Zn2+ for which the fraction of free Zn2+ in soluble Zn ranged from 2.3 to 87% (mean 43%). Five of the agricultural soils had detectable free Cd2+ with fractions of free metal ranging from 59 to 102% (mean 75%). For the contaminated soils with detectable free metal concentrations, the fraction of free metal as a percentage of soluble metal varied from 9.9 to 97% (mean 50%) for Zn2+, from 22 to 86% (mean 49%) for Cd2+, from 0.4 to 32.1% (mean 5%) for Cu2+, and from 2.9 to 48.8% (mean 20.1%) for Pb2+. For the contaminated soils, the equilibrium speciation programs GEOCHEM and WHAM Model VI provided reasonable estimates of free Zn2+ fractions in comparison to the measured fractions (R2 approximately 0.7), while estimates of free Cd2+ fractions were less agreeable (R2 approximately 0.5). The models generally predicted stronger binding of Cu2+ to DOC and hence lower fractions of free Cu2+ as compared with the observed fractions. The binding of Cu2+ and Pb2+ to DOC predicted by WHAM Model VI was much strongerthan that predicted by GEOCHEM.  相似文献   
677.
678.
Predictors and outcomes of benefit finding, positive reappraisal coping, and posttraumatic growth were examined using interviews and questionnaires from a longitudinal study of women with early-stage breast cancer followed from primary medical treatment completion to 3 (n=92) and 12 months (n=60) later. Most women (83%) reported at least 1 benefit of their breast cancer experience. Benefit finding (i.e., identification of benefits, number of benefits), positive reappraisal coping, and posttraumatic growth had distinct significant predictors. Positive reappraisal coping at study entry predicted positive mood and perceived health at 3 and 12 months and posttraumatic growth at 12 months, whereas benefit finding did not predict any outcome. Findings suggest that benefit finding, positive reappraisal coping, and posttraumatic growth are related, but distinct, constructs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
679.
Accurate comprehension of safety signs plays a critical part in warning construction workers of potential work hazards. However, existing studies have rarely investigated construction workers' comprehension of safety signs at construction sites. Moreover, existing evaluation methods are generally based on subjective behavior tests, questionnaires, and interviews. Therefore, this study examined the effects of semantic congruity on the comprehension of safety signs, including two sign types (prohibition vs. warning signs) and two conditions (semantic congruence vs. incongruence), combining event-related potentials and time-frequency analysis measurements. Adopting the S1-S2 paradigm, electroencephalogram data were recorded when participants decided whether S1 and S2 were semantically congruent or not. Results showed that the semantically incongruent safety sign-word pairs elicited larger N400 amplitudes and increased theta (3–8 Hz) power in 300–420 ms. The amplitude of N400 in the semantically incongruent condition of the warning sign-word pairs was more negative than that for the prohibition sign-word pairs, while there were no significant differences between the prohibition and warning sign-word pairs in the semantically congruent condition. A greater late positive potential (LPP) (550–750 ms) was also elicited in the semantically incongruent safety sign-word pairs, which was different from previous studies that observed larger LPP in congruent conditions. These results suggest complicated cognitive mechanisms of safety sign comprehension in construction workers. This study extends safety sign comprehension research by using electrophysiological approaches and provides useful indicators for researchers or safety engineers to measure the semantic congruity of proposed sign designs.  相似文献   
680.
Crises do not affect populations equally but expose and exacerbate long-standing vulnerabilities and inequalities. Recovery language such as ‘build back better’, or ‘bounce forward’ has been criticised for neglecting underlying inequalities. This paper reports on the process and early outcomes of an inclusive Community Recovery Planning process for the Falkland Islands, in response to Covid-19. The Falkland Islands is home to a complex community, with close ties and short power distances (due to its small size and remoteness), with differences institutionalised in citizenship statuses and entitlements, and shaped by geopolitical tensions. We aimed to use the ‘pandemic as a portal’, seeking out previously ‘less heard’ voices, to make visible previously hidden impacts, and initiate incremental systemic change to tackle them. Community Impact Assessments evidenced specific areas of vulnerability (e.g., housing and income insecurity) and inequalities, largely shaped by differing citizenship status. In tandem with other government currents, the Community Recovery Planning process has contributed to progressive policy changes in Equalities legislation and Income Support. We offer this paper as a demonstration of our methodology for inclusive recovery planning that could be adapted elsewhere. We argue that the inclusion of previously unheard voices contributed to incremental systemic change to reduce inequalities.  相似文献   
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