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In response to the ever increasing need to develop more efficient and sustainable methods for removing heavy metal contaminants from aqueous systems, the following article reports on the design of highly mesoporous alginate-derived materials (Starbon®) and their application to the adsorption of heavy metals. Using the Starbon® process to expand, dry and pyrolyse an inherently porous polysaccharide precursor, it was possible to produce mesoporous materials (BJH mesopore volumes 0.81-0.94â cm3 g-1) with large surface areas (157-297â m2 g-1) across a range of low pyrolysis temperatures (200-300 °C). The mechanisms of thermal decomposition were explored in terms of chemical and structural changes using N2-sorption porosimetry, thermogravimetric analysis, titration, FT-IR spectroscopy and 13C NMR spectroscopy. It was found that, as a result of intermolecular dehydration and crosslinking, sufficient chemical stability is obtained by the intermediate temperature of 250 °C, with limited improvement seen at higher temperatures. In addition, the materials retained large metal adsorption capacities (0.70-1.72â mmol g-1) as well as strong selectivity for Cu2+ ions (over Co2+ and Ni2+), as compared to commercial petrochemical-derived cation exchange resin Amberlite™ Mac 3H. Thus, highlighting the potential of Starbon® materials as a sustainable answer to the widespread problem of heavy metal-contaminated wastewaters.
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INTRODUCTION: Alcohol abstinence remains common among adults globally, although low and middle-income countries are experiencing declines in abstention. The effect of alcohol policies on lifetime abstinence is poorly understood. The International Alcohol Control (IAC) policy index was developed to benchmark and monitor the uptake of effective alcohol policies and has shown strong associations with alcohol per capita consumption and drinking patterns. Uniquely, the index incorporates both policy 'stringency' and 'impact', reflecting policy implementation and enforcement, across effective policies. Here we assessed the association of the IAC policy index with lifetime abstinence in a diverse sample of jurisdictions. METHODS: We conducted a cross-sectional analysis of the relationship between the IAC policy index score, and its components, and lifetime abstinence among adults (15+ years) in 13 high and middle-income jurisdictions. We examined the correlations for each component of the index and stringency and impact separately. RESULTS: Overall, the total IAC policy index scores were positively correlated with lifetime abstinence (r = 0.76), as were both the stringency (r = 0.62) and impact (r = 0.82) scores. Marketing restrictions showed higher correlations with lifetime abstinence than other policy domains (r = 0.80), including restrictions on physical availability, pricing policies and drink-driving prevention. DISCUSSION AND CONCLUSION: Our findings suggest that restricting alcohol marketing could be an important policy for the protection of alcohol abstention. The IAC policy index may be a useful tool to benchmark the performance of alcohol policy in supporting alcohol abstention in high and middle-income countries.
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Consumo de Bebidas Alcoólicas , Política Pública , Adulto , Humanos , Consumo de Bebidas Alcoólicas/prevenção & controle , Estudos Transversais , Marketing , EtanolRESUMO
Ultrasound (US) image guidance is widely used for minimally invasive procedures, but the invasive medical devices (such as metallic needles), especially their tips, can be poorly visualised in US images, leading to significant complications. Photoacoustic (PA) imaging is promising for visualising invasive devices and peripheral tissue targets. Light-emitting diodes (LEDs) acting as PA excitation sources facilitate the clinical translation of PA imaging, but the image quality is degraded due to the low pulse energy leading to insufficient contrast with needles at deep locations. In this paper, photoacoustic visualisation of clinical needles was enhanced by elastomeric nanocomposite coatings with superficial and interstitial illumination. Candle soot nanoparticle-polydimethylsiloxane (CSNP-PDMS) composites with high optical absorption and large thermal expansion coefficients were applied onto the needle exterior and the end-face of an optical fibre placed in the needle lumen. The excitation light was delivered at the surface by LED arrays and through the embedded optical fibre by a pulsed diode laser to improve the visibility of the needle tip. The performance was validated using an ex-vivo tissue model. An LED-based PA/US imaging system was used for imaging the needle out-of-plane and in-plane insertions over approach angles of 20 deg to 55 deg. The CSNP-PDMS composite conferred substantial visual enhancements on both the needle shaft and the tip, with an average of 1.7- and 1.6-fold improvements in signal-to-noise ratios (SNRs), respectively. With the extended light field involving extracorporeal and interstitial illumination and the highly absorbing coatings, enhanced visualisation of the needle shaft and needle tip was achieved with PA imaging, which could be helpful in current US-guided minimally invasive surgeries.
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Nanocompostos , Agulhas , Iluminação , Análise Espectral , UltrassonografiaRESUMO
In this paper, we introduce the idea of the bio-socio-material body to think through the body politics that emerge within the nexus of health, well-being and domestic energy consumption as people age. Our work draws upon an ethnographic study with older Australians in regional New South Wales, Australia. We enrich social practice theory conceptualisations by foregrounding the body as a dynamic bio-socio-material entity that shapes and is shaped by practices. In doing so, we draw attention to the body politics of managing health, well-being and energy consumption while trying to age successfully. We identify that the bio-socio-material dimensions of the body play an important role in how health, well-being and energy practices are performed. Energy practices are bound up in understandings of health and well-being as an ongoing and contingent process. Here, the use of energy and appliances becomes integral to how people negotiate and work towards successful ageing. We found that embodied practices of health, well-being and energy consumption are linked to biological, emotional, affective, social and material concerns that create body politics. These include tensions and challenges relating to health and vitality, caring for the sick and the dying, maintaining good mental health, the affordances of buildings and appliances, energy affordability and billing anxiety, social connectedness, and pleasures and pains. We raise questions emerging from our research on the implications for successful ageing. We call for attention to how health, well-being and energy are imbricated and for policy and programmes that better support older people to navigate the nexus of health, well-being and energy consumption as they age.
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Envelhecimento , Saúde Mental , Idoso , Antropologia Cultural , Austrália , Humanos , PolíticaRESUMO
This study developed a measurement tool to assess stringency and 'on-the-ground' impact of four key alcohol policy domains to create an alcohol policy index suitable for benchmarking alcohol policy and assessing change over time in middle- and high-income countries. It involved a collaboration between researchers in 12 diverse countries: New Zealand; Australia; England; Scotland; Netherlands; Vietnam; Thailand; South Africa; Turkey; Chile; Saint Kitts and Nevis and Mongolia. Data on the four most effective alcohol policy domains (availability, pricing policy, alcohol marketing, drink driving) were used to create an alcohol policy index based on their association with alcohol per capita consumption (APC) of commercial (recorded) alcohol. An innovation was the inclusion of measures of impact along with the stringency of the legislation or regulation. The resulting International Alcohol Control (IAC) Policy Index showed a very high negative correlation (-0.91) with recorded APC. Greater affordability of alcohol, an impact measure taking into account prices paid and countries' Gross Domestic Product, was predictive of higher APC (-0.80). Countries in which more modes of alcohol marketing are legally allowed and used had higher APC. Legislation on outlet density and drink driving predicted APC whereas trading hours did not. While stringency and impact measures varied between domains in terms of relationship with APC, overall, there was a strong correlation between impact and stringency (0.77). The IAC Policy Index, which includes measures of policy stringency and 'on-the-ground' impacts in relation to four key policy areas, was found to be strongly associated with commercial alcohol consumed in a number of diverse country settings. It showed a larger relationship than previous indices that include more policy dimensions. The index provides a relatively simple tool for benchmarking and communication with policy makers to encourage a strong focus on uptake of these four most effective alcohol policies.
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Dual-modality imaging employing complementary modalities, such as all-optical ultrasound and photoacoustic imaging, is emerging as a well-suited technique for guiding minimally invasive surgical procedures. Quantum dots are a promising material for use in these dual-modality imaging devices as they can provide wavelength-selective optical absorption. The first quantum dot nanocomposite engineered for co-registered laser-generated ultrasound and photoacoustic imaging is presented. The nanocomposites developed, comprising CuInS2 quantum dots and medical-grade polydimethylsiloxane (CIS-PDMS), are applied onto the distal ends of miniature optical fibers. The films exhibit wavelength-selective optical properties, with high optical absorption (> 90%) at 532 nm for ultrasound generation, and low optical absorption (< 5%) at near-infrared wavelengths greater than 700 nm. Under pulsed laser irradiation, the CIS-PDMS films generate ultrasound with pressures exceeding 3.5 MPa, with a corresponding bandwidth of 18 MHz. An ultrasound transducer is fabricated by pairing the coated optical fiber with a Fabry-Pérot (FP) fiber optic sensor. The wavelength-selective nature of the film is exploited to enable co-registered all-optical ultrasound and photoacoustic imaging of an ink-filled tube phantom. This work demonstrates the potential for quantum dots as wavelength-selective absorbers for all-optical ultrasound generation.
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OBJECTIVE: To predict readiness for laparoscopic ovariectomy of live dogs on the basis of performance on a high-fidelity laparoscopic abdominal simulator and to determine interrater reliability of the assessment. STUDY DESIGN: Experimental study. SAMPLE POPULATION: Seventeen fourth-year veterinary students. METHODS: After a standardized laparoscopic training course, each participant performed a laparoscopic ovariectomy with a simulator. This performance was scored in real time by two evaluators using a rubric. Participants achieving a score of 112 of 160 performed a laparoscopic ovariectomy in a live dog, supervised by an instructor in the room. Two evaluators scored video recordings of each procedure using the rubric. Participants' opinions about the simulator were collected with a survey. RESULTS: All participants scored above the threshold (range, 126-151) and successfully completed laparoscopic ovariectomy in a live dog, with an average of 10 of 17 participants requiring verbal guidance and 5 of 17 participants requiring intervention from the instructor. Interrater concordance was excellent for the rubrics used to score performance on the simulator (R = 0.91) and in vivo (R = 0.81). All participants agreed that the simulator should be used to assess trainee readiness prior to surgery in a live dog. CONCLUSION: Participants achieving a score of at least 126 of 160 on the simulator were able to perform a laparoscopic ovariectomy in a live dog under supervision. The scoring system for the simulator had excellent interrater concordance. CLINICAL SIGNIFICANCE: This simulator and scoring system can be used in laparoscopic training programs to assess readiness for progression to the operative setting.
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Competência Clínica , Laparoscopia , Ovariectomia , Cirurgia Veterinária , Animais , Simulação por Computador , Cães , Feminino , Humanos , Laparoscopia/veterinária , Reprodutibilidade dos Testes , Cirurgia Veterinária/normas , Inquéritos e QuestionáriosRESUMO
Content expertise in basic science and clinical disciplines does not assure proficiency in teaching. Faculty development to improve teaching and learning is essential for the advancement of veterinary education. The Consortium of West Region Colleges of Veterinary Medicine established the Regional Teaching Academy (RTA) with the focus of "Making Teaching Matter." The objective of the RTA's first effort, the Faculty Development Initiative (FDI), was to develop a multi-institutional faculty development program for veterinary educators to learn about and integrate effective teaching methods. In 2016, the Veterinary Educator Teaching and Scholarship (VETS) program was piloted at Oregon State University's College of Veterinary Medicine. This article uses a case study approach to program evaluation of the VETS program. We describe the VETS program, participants' perceptions, participants' teaching method integration, and lessons learned. A modified Kirkpatrick Model (MKM) was used to categorize program outcomes and impact. Quantitative data are presented as descriptive statistics, and qualitative data are presented as the themes that emerged from participant survey comments and post-program focus groups. Results indicated outcomes and impacts that included participants' perceptions of the program, changes in participant attitude toward teaching and learning, an increase in the knowledge level of participants, self-reported changes in participant behaviors, and changes in practices and structure at the college level. Lessons learned indicate that the following are essential for program success: (1) providing institutional and financial support; (2) creating a community of practice (COP) of faculty development facilitators, and (3) developing a program that addresses the needs of faculty and member institutions.
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Educação em Veterinária , Animais , Docentes , Docentes de Medicina , Bolsas de Estudo , Humanos , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Desenvolvimento de Pessoal , Inquéritos e Questionários , EnsinoRESUMO
BACKGROUND: Gambling is now a well-recognised public health issue and forms the focus of extensive harm reduction initiatives. Recent developments in policy, practice and technology, such relaxation of regulations, the increasing influence of global gambling corporations, and the development of devices such as mobile phone apps and fixed odds betting terminals (FOBTs) mean that the landscape is a complex, dynamic, and fast moving one. Gambling is now practiced using new technologies, in various spaces and places, and features in a range of social surroundings. Therefore, research is needed to inform appropriate gambling harm reduction strategies that can respond to this complex domain. Yet, research and policy approaches to the reduction of gambling harm are predominantly framed through psychological and economic models of individual behaviour, addiction, and 'rational' action. This is beginning to change, with a growing corpus of socio-cultural approaches to gambling research now emerging. METHOD: In this article, we argue the case of recognising gambling as a social practice, the performance of which draws upon multiple elements such as technology and materials, spaces and places, language and discourse, and structures and agency. We call for a practice theory approach to gambling research that joins efforts to move beyond individual gamblers and their behaviour, to also acknowledge the interaction of multiple elements shaping gambling practices. To achieve this, we suggest that research methods such as visual ethnography can be helpful. CONCLUSION: We set out how a social practice perspective to gambling research can generate different insights and help inform more nuanced and appropriate gambling harm reduction initiatives.
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Comportamento Aditivo/psicologia , Jogo de Azar/psicologia , Redução do Dano , Meio Social , Comportamento Aditivo/prevenção & controle , Jogo de Azar/prevenção & controle , Humanos , Pesquisa , Fatores de RiscoRESUMO
Current methods for the extraction of rhodium carry the highest carbon footprint and worst pollution metrics of all of the elements used in modern technological applications. Improving upon existing methods is made difficult by the limited understanding of the molecular-level chemistry occurring in extraction processes, particularly in the hydrometallurgical separation step. While many of the precious metals can be separated by solvent extraction, there currently exist no commercial extractants for Rh. This is due to its complicated mixed speciation upon leaching into hydrochloric acid, which gives rise to difficulties in designing effective reagents for solvent extraction. Herein we show that the diamidoamine reagent N- n-hexylbis( N-methyl- N- n-octylethylamide)amine transports Rh(III) from aqueous HCl into an organic phase as the monoaquated dianion [RhCl5(H2O)]2- through the formation of an outer-sphere assembly; this assembly has been characterized by experimentation (slope analysis, FT-IR and NMR spectroscopy, EXAFS, SANS, and ESI-MS) and computational modeling. The paper demonstrates the importance of applying a broad range of techniques to obtain a convincing mode of action for the complex processes involved in anion recognition in the solution phase. A consistent and comprehensive understanding of how the ligand operates to achieve Rh(III) selectivity over the competitor anion Cl- has emerged. This knowledge will guide the design of extractants and thus offers promise for improving the sustainability of metal extraction from both traditional mining sources and the recycling of secondary source materials.
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The objective of this study was to investigate the effect of playing video games on the performance of basic laparoscopic skills. The study was an experimental pre-test-post-test comparison group design. Fifty-two students (31 from the Western University of Health Sciences College of Veterinary Medicine and 21 from the Colorado State University College of Veterinary Medicine) completing their first or second year of the veterinary curriculum were randomized into two intervention groups. The intervention consisted of playing the video game Marble Mania on a Nintendo Wii. group L (long) played 18 hours over 6 weeks and group S (short) played 3 hours during the last week of the 6-week intervention period. Before and after the intervention, basic laparoscopic skills for both groups were assessed using a modified McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) instrument. Participants performed two laparoscopic tasks. Results showed that the performance of students improved in both group S and L (p < .05) on both laparoscopic tasks. Both groups showed statistically significant improvement in their post-intervention scores (group L, N = 25, z = -3.711, p < .001, r = 0.742; group S, N = 27, z = -3.016, p < .003, r = 0.580). There was no significant difference in the degree of improvement between group S and group L. The results suggest that playing Marble Mania on a Wii for any time duration could be an effective method for veterinary medicine students to improve basic laparoscopic skills, and indicate the needs for additional studies.
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Competência Clínica , Educação em Veterinária , Estudantes de Medicina/psicologia , Jogos de Vídeo , Colorado , Simulação por Computador , Humanos , Laparoscopia , Análise e Desempenho de TarefasRESUMO
With the recognition of shelter medicine as a sub-discipline of veterinary medicine, many veterinary programs are including clinical shelter experiences in their curricula. A concurrent mixed-methods study was designed with the aim to determine the effectiveness of a 4-week clinical shelter medicine program on students' perception of canine and feline surgical proficiency and shelter medicine knowledge as well as gain information on student attitudes toward shelter medicine and interest in pursuing this career path. Year 4 veterinary students at Western University of Health Sciences who were enrolled in a shelter medicine externship from 2014 to 2016 were invited to complete pre- and post-course online surveys. Of the 168 enrolled students, 77.4% were invited to participate, and 114 completed the survey. There was no statistically significant difference in student veterinary career interest before and after completing the externship. There was an overall increase in student rating of their ability to perform six shelter medicine tasks as well as ovariohysterectomy/ovariectomy (OVH/OE) and castration surgeries after completing their externship; all were statistically significant ( p < .001). There was a statistically significant difference in the proportion of students who were familiar with the Asilomar Accords and the Association of Shelter Veterinarians (ASV) Guidelines for Standards of Care in Animal Shelters after completion of their externship ( p < .001). Students largely supported pediatric spay and neuter, stating it was an effective means of population control. Based on the themes that emerged from the qualitative analysis, it appeared most students had an accurate understanding of the term no-kill.
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Castração/veterinária , Gatos/cirurgia , Cães/cirurgia , Educação em Veterinária , Estudantes/psicologia , Animais , Castração/educação , Feminino , MasculinoRESUMO
Despite calls for more socio-technical research on energy, there is little practical advice to how narratives collected through qualitative research may be melded with technical knowledge from the physical sciences such as engineering and then applied in energy efficiency social action strategies. This is despite established knowledge in the environmental management literature about domestic energy use regarding the utility of social practice theory and narrative framings that socialise everyday consumption. Storytelling is positioned in this paper both as a focus for socio-technical energy research, and as one potential practical tool that can arguably enhance energy efficiency interventions. We draw upon the literature on everyday social practices, and storytelling, to present our framework called 'collective video storytelling' that combines scientific and lay knowledge about domestic energy use to offer a practical tool for energy efficiency management. Collective video storytelling is discussed in the context of Energy+Illawarra, a 3-year cross-disciplinary collaboration between social marketers, human geographers, and engineers to target energy behavioural change within older low-income households in regional NSW, Australia.
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Comunicação , Conservação de Recursos Energéticos , Marketing Social , Austrália , Humanos , Narração , Pesquisa QualitativaRESUMO
INTRODUCTION AND AIM: To report data on the implementation of alcohol policies regarding availability and marketing, and drink driving, along with ratings of enforcement from two small high-income to three high-middle income countries, and one low-middle income country. METHOD: This study uses the Alcohol Environment Protocol, an International Alcohol Control study research tool, which documents the alcohol policy environment by standardised collection of data from administrative sources, observational studies and interviews with key informants to allow for cross-country comparison and change over time. RESULTS: All countries showed adoption to varying extents of key effective policy approaches outlined in the World Health Organization Global Strategy to Reduce the Harmful Use of Alcohol (2010). High-income countries were more likely to allocate resources to enforcement. However, where enforcement and implementation were high, policy on availability was fairly liberal. Key Informants judged alcohol to be very available in both high- and middle-income countries, reflecting liberal policy in the former and less implementation and enforcement and informal (unlicensed) sale of alcohol in the latter. Marketing was largely unrestricted in all countries and while drink-driving legislation was in place, it was less well enforced in middle-income countries. CONCLUSION: In countries with fewer resources, alcohol policies are less effective because of lack of implementation and enforcement and, in the case of marketing, lack of regulation. This has implications for the increase in consumption taking place as a result of the expanding distribution and marketing of commercial alcohol and consequent increases in alcohol-related harm.
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Consumo de Bebidas Alcoólicas/epidemiologia , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Dirigir sob a Influência/prevenção & controle , Política de Saúde , Consumo de Bebidas Alcoólicas/prevenção & controle , Transtornos Relacionados ao Uso de Álcool/prevenção & controle , Bebidas Alcoólicas/economia , Comércio/estatística & dados numéricos , Comparação Transcultural , Coleta de Dados , Dirigir sob a Influência/legislação & jurisprudência , Humanos , Marketing/legislação & jurisprudência , Fatores de TempoRESUMO
Focused Clinical Question: Are there any extraoral uses for intraoral soft tissue grafts? Summary: Despite extensive literature on the intraoral uses of soft tissue autografts harvested from oral sites, the periodontal literature is lacking information on the extraoral uses of such grafts. The purpose of this article is to review the autologous use of certain oral soft tissue grafts for extraoral indications. A literature search revealed that several medical specialties, including otolaryngology, ophthalmology, dermatology, plastic surgery, and urology, have a track record of positive outcomes with the use of free gingival, buccal fat pad, and buccal mucosa grafts for a wide variety of reconstructive procedures at diverse body sites. Conclusions: The numerous successful extraoral uses of oral soft tissue autografts underscore the versatility of these tissues in reconstructive surgery and suggest there is potential for collaboration between periodontal and medical specialists for the benefit of patients in need of such reconstructions. Broader awareness of these applications of oral soft tissue grafts could help expand their current uses and would allow practitioners to better answer possible patient inquiries.
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BACKGROUND: Since 2008, Australia has seen the rapid emergence of marketing for online and mobile sports wagering. Previous research from other areas of public health, such as tobacco and alcohol, has identified the range of appeal strategies these industries used to align their products with culturally valued symbols. However, there is very limited research that has investigated the tactics the sports wagering industry uses within marketing to influence the consumption of its products and services. METHOD: This study consisted of a mixed method interpretive content analysis of 85 sports wagering advertisements from 11 Australian and multinational wagering companies. Advertisements were identified via internet searches and industry websites. A coding framework was applied to investigate the extent and nature of symbolic appeal strategies within advertisements. RESULTS: Ten major appeal strategies emerged from this analysis. These included sports fan rituals and behaviours; mateship; gender stereotypes; winning; social status; adventure, thrill and risk; happiness; sexualised imagery; power and control; and patriotism. Symbols relating to sports fan rituals and behaviours, and mateship, were the most common strategies used within the advertisements. DISCUSSION/CONCLUSIONS: This research suggests that the appeal strategies used by the sports wagering industry are similar to those strategies adopted by other unhealthy commodity industries. With respect to gambling, analysis revealed that strategies are clearly targeted to young male sports fans. Researchers and public health practitioners should seek to better understand the impact of marketing on the normalisation of sports wagering for this audience segment, and implement strategies to prevent gambling harm.
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Publicidade/estatística & dados numéricos , Jogo de Azar , Marketing/métodos , Esportes , Adolescente , Adulto , Austrália , Telefone Celular , Feminino , Humanos , Internet , Masculino , Adulto JovemRESUMO
BACKGROUND: Chlamydia trachomatis is one of the most frequently reported sexually transmitted infections (STI) in Australia, the UK and Europe. Yet, rates of screening for STIs remain low, especially in younger adults. OBJECTIVE: To assess effectiveness of Chlamydia screening interventions targeting young adults in community-based settings, describe strategies utilized and assess them according to social marketing benchmark criteria. SEARCH STRATEGY: A systematic review of relevant literature between 2002 and 2012 in Medline, Web of Knowledge, PubMed, Scopus and the Cumulative Index to Nursing and Allied Health was undertaken. RESULTS: Of 18 interventions identified, quality of evidence was low. Proportional screening rates varied, ranging from: 30.9 to 62.5% in educational settings (n = 4), 4.8 to 63% in media settings (n = 6) and from 5.7 to 44.5% in other settings (n = 7). Assessment against benchmark criteria found that interventions incorporating social marketing principles were more likely to achieve positive results, yet few did this comprehensively. Most demonstrated customer orientation and addressed barriers to presenting to a clinic for screening. Only one addressed barriers to presenting for treatment after a positive result. Promotional messages typically focused on providing facts and accessing a testing kit. Risk assessment tools appeared to promote screening among higher risk groups. Few evaluated treatment rates following positive results; therefore, impact of screening on treatment rates remains unknown. DISCUSSION: Future interventions should consider utilizing a comprehensive social marketing approach, using formative research to increase insight and segmentation and tailoring of screening interventions. Easy community access to both screening and treatment should be prioritized.
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Infecções por Chlamydia/diagnóstico , Programas de Rastreamento , Marketing Social , Adolescente , Comportamentos Relacionados com a Saúde , Educação em Saúde/métodos , Humanos , Características de Residência , Adulto JovemRESUMO
Copper complexes of the phenolic oxime family of ligands (3-X-salicylaldoximes) are used extensively as metal solvent extractants. Incorporation of electronegative substituents in the 3-position, ortho to the phenol group, can be used to buttress the interligand H-bonding, leading to an enhancement in extractant strength. However, investigation of the relevant H-bonding in these complexes can be exceedingly difficult. Here, we have combined EPR, ENDOR, DFT, and X-ray crystallography to study this effect. Analysis of the (1)H ENDOR data revealed a variation in the Cu···H(16) (oxime proton) distance from 2.92 Å for the unsubstituted complex [Cu(L(2))2] to 3.65 Å for the X = CH2N(C6H13)2 substituted complex [Cu(L(3))2]. DFT calculations showed that this variation is caused by changes to the length and strength of the H-bond between the oximic hydrogen and the phenolate oxygen. Noticeable changes to the Cu···H(15) (azomethine proton) distances and the Cu···N bonding parameters were also observed in the two complexes, as revealed through the (N)A and (N)Q ENDOR data. Distortions in the structure of the complex and variations in the oximic proton to phenolate oxygen H-bond strength caused by the substituent (X) were confirmed by DFT and X-ray crystallography. DFT directly evidenced the importance of the interaction between H(16) and the amine nitrogen of CH2N(C6H13)2 in the buttressed complex and indicated that the high strength of this interaction may not necessarily lead to an enhancement of copper extraction, as it can impose an unfavorable geometry in the inner coordination sphere of the complex. Therefore, ENDOR, DFT, and X-ray structural data all indicate that the aminomethyl substituent (X) ortho to the phenolic oxygen atom provides a particularly strong buttressing of interligand H-bonding in these copper complexes and that these outer sphere interactions can significantly influence structure and stability.
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High anion selectivity for PtCl6(2-) over Cl(-) is shown by a series of amidoamines, R(1)R(2)NCOCH2CH2NR(3)R(4) (L1 with R(1) = R(4) = benzyl and R(2) = R(3) = phenyl and L3 with R(1) = H, R(2) = 2-ethylhexyl, R(3) = phenyl and R(4) = methyl), and amidoethers, R(1)R(2)NCOCH2CH2OR(3) (L5 with R(1) = H, R(2) = 2-ethylhexyl and R(3) = phenyl), which provide receptor sites which extract PtCl6(2-) preferentially over Cl(-) in extractions from 6 M HCl solutions. The amidoether receptor L5 was found to be a much weaker extractant for PtCl6(2-) than its amidoamine analogues. Density functional theory calculations indicate that this is due to the difficulty in protonating the amidoether to generate a cationic receptor, LH(+), rather than the latter showing weaker binding to PtCl6(2-). The most stable forms of the receptors, LH(+), contain a tautomer in which the added proton forms an intramolecular hydrogen bond to the amide oxygen atom to give a six-membered proton chelate. Dispersion-corrected DFT calculations appear to suggest a switch in ligand conformation for the amidoamine ligands to an open tautomer state in the complex, such that the cationic N-H or O-H groups are also readily available to form hydrogen bonds to the PtCl6(2-) ion, in addition to the array of polarized C-H bonds. The predicted difference in energies between the proton chelate and nonchelated tautomer states for L1 is small, however, and the former is found in the X-ray crystal structure of the assembly [(L1H)2PtCl6]. The DFT calculations and the X-ray structure indicate that all LH(+) receptors present an array of polarized C-H groups to the large, charge diffuse PtCl6(2-) anion resulting in high selectivity of extraction of PtCl6(2-) over the large excess of chloride.
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BACKGROUND: Despite a complex and multi-faceted alcohol policy environment in Australia, there are few comprehensive reviews of national and state alcohol policies that assess their effectiveness and research support. In mapping the Australian alcohol policy domain and evaluating policy interventions in each of the core policy areas, this article provides a useful resource for researchers. The implications for protecting public health emanating from this mapping and evaluation of alcohol policy are also discussed. METHODS: This review considered data from: published primary research; alcohol legislation, strategies and alcohol-related press releases for all levels and jurisdictions of Australian government; international publications by prominent non-governmental organisations; and relevant grey literature. These were organised and evaluated using the established framework offered by Thomas Babor and colleagues. RESULTS: Findings indicated great variability in alcohol initiatives across Australia, many of which do not reflect what is currently considered to be evidence-based best practice. CONCLUSIONS: Research showing increasing alcohol-related harms despite steady levels of consumption suggests a need to pursue alcohol policy initiatives that are supported by evidence of harm-reduction. Future initiatives should aim to increase existing alcohol controls in line with suggested best practice in order to protect public health in Australia.