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1.
Drug Alcohol Rev ; 42(6): 1338-1348, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37380168

RESUMEN

INTRODUCTION: Scotland implemented a minimum price per unit of alcohol (MUP) of £0.50 in May 2018 (1 UK unit = 10 mL/8 g ethanol). Some stakeholders expressed concerns about the policy having potential negative consequences for people with alcohol dependence. This study aimed to investigate anticipated impacts of MUP on people presenting to alcohol treatment services in Scotland before policy implementation. METHODS: Qualitative interviews were conducted with 21 people with alcohol dependence accessing alcohol treatment services in Scotland between November 2017 and April 2018. Interviews examined respondents' current and anticipated patterns of drinking and spending, effects on their personal life, and their views on potential policy impact. Interview data were thematically analysed using a constant comparison method. RESULTS: Three key themes were identified: (i) strategies used to manage the cost of alcohol and anticipated responses to MUP; (ii) broader effects of MUP; and (iii) awareness and preparedness for MUP. Respondents expected to be impacted by MUP, particularly those on low incomes and those with more severe dependence symptoms. They anticipated using familiar strategies including borrowing and reprioritising spending to keep alcohol affordable. Some respondents anticipated negative consequences. Respondents were sceptical about the short-term benefits of MUP for current drinkers but felt it might prevent harm for future generations. Respondents had concerns about the capacity of treatment services to meet support needs. DISCUSSION AND CONCLUSIONS: People with alcohol dependence identified immediate concerns alongside potential long-term benefits of MUP before its introduction. They also had concerns over the preparedness of service providers.


Asunto(s)
Bebidas Alcohólicas , Alcoholismo , Humanos , Alcoholismo/terapia , Etanol , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/prevención & control , Escocia , Costos y Análisis de Costo , Investigación Cualitativa , Comercio
2.
Materials (Basel) ; 15(6)2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35329445

RESUMEN

Ferrochrome slag (FS) and tundish slag (TS) are two typical slags containing high contents of Cr2O3 (3.88 wt.%) and MnO (18.69 wt.%), respectively. In this study, batches of ceramics were prepared from FS and TS, and their Cr/Mn leaching behaviors, mechanical properties and microstructures were investigated. Results showed that ceramics with 80 wt.% FS or 85 wt.% TS had acceptable properties. By controlling its composition and sintering temperature, pyroxene or spinel phases could become the main crystalline phases of the fired ceramics containing either of the two slags. For both slag series, pyroxene phases contributed to higher bending strengths, whereas spinel phases led to lower Cr/Mn leaching rates. Both ceramic containing 20 wt.% FS and ceramic containing 85 wt.% TS had the main crystals of pyroxene phases and possessed the highest bending strengths (FS20: 114.52 MPa and TS85: 124.61 MPa). However, both ceramic containing 80 wt.% FS and ceramic containing 25 wt.% TS with main crystals from the spinel phases had the lowest Cr/Mn leaching rates (FS80: Cr 0.05% and TS25: Mn 0.43%). Therefore, optimum designs for the compositions of ceramics from different slags were achieved by changing the proportions of pyroxene and spinel phases to obtain a balance between the high strengths of materials and the stable retention of heavy metal ions. This study provides an important basis for long-term research on the large-scale reuse of heavy metal-containing slags in the ceramic industry.

3.
J Hazard Mater ; 399: 122845, 2020 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-32512277

RESUMEN

A novel process is proposed in this paper for a green and efficient utilization of copper slag. The basic premise involved the addition of different amounts of Na2O into molten copper slag and evaluation of the effects on the magnetic fraction and the properties of ceramics generated from the non-magnetic residue, and mechanisms of the effects were further studied by XRD, SEM, EDS, viscosity test, hysteresis loop and FTIR. The results showed that Na2O additions dropped the viscosity of the slag markedly, which promoted the growth of magnetite, but decrease quantity of magnetite due to oxidization of Fe2+ and precipitation of crystals containing Fe3+. With the addition of 4 % Na2O, solidification temperature of slag decreased from 1790 K to 1530 K, optimum iron recovery rate of 81.08 % was achieved. Na2O as flux in ceramics obviously reduced its sintering temperature and meantime decreased its bending strength because of insufficient crystallization of its main minerals. The non-magnetic residue from magnetic separation of slag with addition of 4% Na2O was converted into ceramics with a much low sintering temperature of 1268 K (995 °C) and qualified bending strength of 64.5 MPa.

4.
J Endod ; 35(10): 1363-7, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19801231

RESUMEN

INTRODUCTION: Single use of endodontic nickel-titanium (NiTi) instruments has been recommended to reduce instrument fatigue and the possibility of cross-contamination. The purpose of this study was to evaluate the defects of three NiTi rotary systems (ProFile series 29 [Dentsply Tulsa Dental Products, Tulsa, OK], ProFile [Dentsply Tulsa Dental Products], and ProTaper [Dentsply Maillefer, Ballaigues, Switzerland]) that were discarded after single use by two endodontic clinics. METHODS: A total of 1,071 ProFile .04, 432 ProFile series 29 .04, and 1,895 ProTaper rotary instruments were collected over 12 months and analyzed. These discarded files were ultrasonically cleaned and autoclaved. The lateral view of the deformed instruments and fracture surface of the separated instruments were examined by scanning electron microscopy. Qualitative X-ray energy-dispersive spectrophotometric (EDS) spot analyses were performed on particles adherent to the surface and those apparently wedged in surface microcracks. RESULTS: There were no fractures or deformations in the ProFile Series 29. The overall prevalence of deformation was 2.9% in ProTaper and 0.75% in ProFile. The incidence of instrument separation was 0.26% in ProTaper, whereas no fractures occurred in ProFile instruments. The majority of instrument defects occurred in size 25 (6/8) for ProFile and in Sx for ProTaper (22/60). The separated ProTaper instruments failed mostly because of shear stress. Some surface deposits and microcracks were found in single-use NiTi instruments. EDS indicated that surface deposits may be dentin. CONCLUSION: The risk of NiTi rotary instrument fracture in the canal is low when a new instrument is used by experienced endodontists. The most common cause of failure, albeit rare, was shear failure.


Asunto(s)
Aleaciones Dentales/química , Níquel/química , Preparación del Conducto Radicular/instrumentación , Titanio/química , Endodoncia , Diseño de Equipo , Falla de Equipo , Humanos , Ensayo de Materiales , Fenómenos Mecánicos , Microscopía Electrónica de Rastreo , Rotación , Espectrometría por Rayos X , Espectrofotometría , Esterilización , Estrés Mecánico , Propiedades de Superficie , Ultrasonido
5.
J Am Dent Assoc ; 135(7): 903-9, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15354901

RESUMEN

BACKGROUND: Posts frequently are used to retain buildups. The authors examined the effects of post space preparation with Gates-Glidden drills on residual dentin thickness in distal roots of mandibular molars. METHODS: The authors embedded 26 root-treated mandibular molars in endodontic cubes and sectioned them perpendicularly to their long axis at 1.8-millimeter intervals. They placed Gates-Glidden drills nos. 3, 4, 5 and 6 sequentially to 5 mm short of working length in the distal canals. After using each drill size, the authors measured the dentin thickness from light microscopic images of the tooth slices. RESULTS: The authors analyzed data to detect changes resulting from canal instrumentation. They performed statistical analysis by partitioning the variability in a nested analysis of variance. Strip perforations occurred with a no. 4 Gates-Glidden drill 7.3 percent of the time and more frequently with larger drills. After endodontic treatment alone, the canal wall on the furcal side was less than 1 mm thick 82 percent of the time and less than 0.5 mm thick 17.5 percent of the time. CONCLUSIONS: Dentin thickness correlates inversely to post space diameter. A no. 4 Gates-Glidden drill caused strip perforations in 7.3 percent of the canals studied, and therefore the authors recommend that Gates-Glidden drills larger than a no. 3 not be used in these roots. After endodontic treatment, the furcation-side dentin thickness was less than 1 mm in 82 percent of the teeth. CLINICAL IMPLICATIONS: Post space preparation in mandibular molars carries significant risk of perforation. Post space in such teeth should be limited to the endodontically prepared canal.


Asunto(s)
Dentina/anatomía & histología , Técnica de Perno Muñón , Preparación del Conducto Radicular/instrumentación , Instrumentos Dentales/efectos adversos , Diseño de Equipo , Humanos , Mandíbula , Diente Molar , Preparación del Conducto Radicular/efectos adversos
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