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1.
Sci Total Environ ; 855: 158870, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36155048

RESUMO

Hydrometallurgical processing of electronic waste produces copper (Cu)-containing wastewater. Recycling of Cu is thus crucial, as it reduces the Cu impact on the environment, and increases Cu sustainability in industry. Vacuum distillation provides excellent performance in both metals removal from aqueous solution, metal recovery, and metal impregnation to porous material. Thus, this work aimed to both utilize a vacuum distillation to remove heavy metals (Cu, Na, Ni, Zn and Fe) and recover copper nitrate hydroxide (Cu2NO3(OH)3) from Cu-containing wastewater in industrial applications (e.g., mordant agent in dyeing and pigment for glass), as well as prepare copper sulfide (CuS) impregnated activated carbon for mercury (Hg0) adsorption. The experimental results indicated a vacuum distillation metals removal efficiency of over 99.99 % at 60 °C and -72 cm Hg. Additionally, the copper nitrate hydroxide (Cu2NO3(OH)3) crystalline solid derived from the vacuum distillation process achieved 77 % purity, and the copper sulfide impregnated activated carbon (CuSAC) adsorbents were prepared by adding activated carbon (AC) during the vacuum distillation process. In adsorption tests, 50 % CuSAC exhibited the greatest gaseous mercury (Hg0) adsorption performance, and it was noted that a high adsorption temperature of 175 °C negatively impacted Hg0 adsorption of 50 % CuSAC due to mercury sulfide (HgS) decomposition. Furthermore, in a simulated flue gas (SFG) environment, Hg0 capture by CuSAC was shown to be slightly obstructed. In addition, mercury temperature-programmed desorption (Hg-TPD) identified that HgS was the dominant species among adsorbed Hg species of Hg-laden 50 % CuSAC, indicating that Hg0 capture of CuSAC was mainly facilitated by sulfur active sites. As such, the vacuum distillation technique proved to efficiently remove metals and leads to successful preparation of adsorbent for Hg. Therefore, the process is an effective treatment method for Cu-containing wastewater, and can be practically applied to capture or recycle Cu in the industry in the future.


Assuntos
Mercúrio , Metais Pesados , Mercúrio/análise , Adsorção , Carvão Vegetal , Águas Residuárias , Gases , Cobre , Nitratos , Destilação , Vácuo , Sulfetos , Hidróxidos
2.
Environ Pollut ; 316(Pt 1): 120555, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36332709

RESUMO

Due to anthropogenic activities, heavy metals are discharged into the hydrosphere and deposit onto the sediment. Heavy metals remobilize through physical disturbance and change in environmental conditions, posing a risk to environments and human health. Among several remediation methods, active layer capping is considered to be more feasible due to its financial and technical advantages; however, its long-term effects remain unknown. To overcome this problem, this work applied a novel, recoverable amendment, sulfurized magnetic biochar (SMBC), to remediate multiple heavy metal (Cu, Ni, Zn, Cr, Hg, and MeHg) contaminated sediment. Physiochemical characterization shows magnetite (Fe3O4) crystalline in both magnetic biochar (MBC) and SMBC, with such characteristics resulting in a greater surface area (324.9 and 346.3 m2/g) than BC (39.6 m2/g) and SBC (65.0 m2/g). FeS crystalline was also observed in SMBC, which plays an important role in controlling heavy metal release from sediment. Microcosm experiments indicated the effectiveness of SMBC in lowering aquatic Cu, Ni, Zn, Hg, and MeHg releases was significantly greater than the other three biochar materials. Notably, the recovery of SMBC by magnetism was 87%, demonstrating the exceptional recoverability of SMBC from seawater and sediment. Based on its robust capability in lowering Cu, Ni, Zn, Hg, and MeHg release and excellent recoverability from seawater and sediment, this technique represents a practical alternative to conventional approaches for heavy metal immobilization from sediment.


Assuntos
Mercúrio , Metais Pesados , Poluentes Químicos da Água , Humanos , Carvão Vegetal/química , Fenômenos Magnéticos , Metais Pesados/química , Poluentes Químicos da Água/análise , Sedimentos Geológicos
3.
J Hazard Mater ; 420: 126546, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34252671

RESUMO

Wet flue gas desulfurization (WFGD) simultaneously removes Hg and SO2 from coal-fired power plant flue gas streams. Hg0 re-emission occurs when the dissolved Hg(II) is converted to a volatile form (i.e., Hg0) that can be subsequently emitted into the ambient air from WFGD wastewater aeration basins. Others have shown that Hg0 re-emission depends on pH, temperature, ligands (Cl, Br, I, F, SO32-, SO42-, NO3-, SCN-, and ClO-), O2, minerals (Se and As), and metals (Fe and Cu) in WFGD wastewater. Still others have shown Hg0 re-emission restriction via inhibitor addition (adsorbents and precipitators). This is the first review that summarizes the complex and inconsistently reported Hg0 re-emission mechanisms, updates misconceptions related to Hg(II) complexation and reduction, and reviews applications of inhibitors that convert aqueous Hg(II) into stable solid forms to prevent gaseous Hg0 formation and release.


Assuntos
Poluentes Atmosféricos , Mercúrio , Poluentes Atmosféricos/análise , Carvão Mineral , Gases , Mercúrio/análise , Centrais Elétricas , Águas Residuárias
4.
Appl Psychophysiol Biofeedback ; 46(4): 347-358, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34308526

RESUMO

We assessed the feasibility of using a consumer friendly, heart rate variability biofeedback (HRVB) wearable device in conjunction with a remote stress management coach to reduce symptoms of anxiety. We utilized a discreet, continuously wearable electrocardiogram device, the Lief Smart Patch, which measures and records heart rate and HRV in real time, and guides HRVB exercises using vibrations and visual cues. During the 8-week study, participants (N = 14) wore the Lief Smart Patch, participated in HRVB with the device, utilized the mobile app, and communicated with a remote stress management coach. We collected self-report survey responses to measure symptoms of anxiety (GAD-2) and depression (PHQ-2) every 2 weeks, as well as HRV data throughout the study. Participants' mean GAD-2 score began at 4.6 out of 6. By the trial's completion, the group's mean GAD-2 score dropped to 1.7 (t(13) = 11.0, p < .001) with only 2 of the 14 subjects remaining over the clinical threshold of high anxiety. Similarly, the group's mean PHQ-2 score dropped from 2.93 to 1.29 (t(13) = 3.54, p < .01). In addition, participants increased their HRV (RMSSD) by an average of + 11.4 ms after participating in a low dose biofeedback exercise. These findings suggest that engaging in HRVB through a discreet wearable device in conjunction with a remote stress management program may be effective for reducing symptoms of anxiety and depression.


Assuntos
Biorretroalimentação Psicológica , Dispositivos Eletrônicos Vestíveis , Ansiedade/terapia , Biorretroalimentação Psicológica/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Projetos Piloto
5.
Am J Manag Care ; 22(11): e368-e374, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27849348

RESUMO

OBJECTIVES: To illustrate a more comprehensive view of value associated with medicines treating a highly severe illness and to apply these insights to estimate the costs and benefits of 3 treatments for multiple sclerosis (MS): Avonex, Tysabri, and Tecfidera. STUDY DESIGN: Retrospective study spanning 2002 to 2013. We used economic theory to derive the value of therapy to patients with MS and to individuals who face the risk of contracting MS in the future, under the alternative assumptions that therapies were fully insured or paid for out of pocket. METHODS: Models were parameterized through secondary data analysis and targeted literature review. Estimates of individual value were aggregated to the societal level using therapy-specific treatment prevalence rates. Aggregate consumer value was compared with manufacturer revenue. RESULTS: In the baseline model, Avonex, Tysabri, and Tecfidera generated $46.2 billion of total value to consumers, almost one-third of which accrued to those without MS. The total value to consumers was double manufacturer revenue. Results were qualitatively robust to the use of alternate epidemiological and economic parameters. We found that value to the healthy is positively related to disease severity, and that value to both the sick and the healthy are larger when costs are shared via health insurance. CONCLUSIONS: Theory predicts that treatments for severe disease provide "peace of mind" value to the healthy. Avonex, Tysabri, and Tecfidera have generated significant social value, a large majority of which accrues to consumers. Future economic valuations of medical technology should consider both the potential value to the healthy and the effects of insurance.


Assuntos
Efeitos Psicossociais da Doença , Cobertura do Seguro/economia , Programas de Assistência Gerenciada/economia , Esclerose Múltipla/economia , Adulto , Doença Crônica , Estudos de Coortes , Terapia Combinada , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econômicos , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/terapia , Estudos Retrospectivos , Índice de Gravidade de Doença , Estados Unidos , Adulto Jovem
6.
AIDS Educ Prev ; 27(4): 362-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26241385

RESUMO

Improvements spearheaded by the World Health Organization in antenatal HIV counseling in sub-Saharan Africa from 2004 to 2011 have seen a parallel increase in HIV testing. We sought to determine the extent to which the use of choice architecture principles (one that introduces an opt-out option as the default) affect uptake of HIV testing, above and beyond individual-level attitudes and cognitions. Demographic and Health Survey data collected between 2004 and 2011 from Zimbabwe (N = 1,330) and Malawi (N = 4,043)--countries where over 10% of adults have HIV--were analyzed. We explored the influence of demographic variables, modes of knowledge about HIV, stigma against people living with HIV, attitudes about spousal abuse, and whether or not HIV testing had been offered during antenatal visits. Results demonstrated that, taking into account secular trends in higher testing rates, structural-level support was the strongest predictor of HIV testing above and beyond individual-level attitudes and cognitions.


Assuntos
Comportamento de Escolha , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Programas de Rastreamento/métodos , Estigma Social , Adolescente , Adulto , Aconselhamento , Tomada de Decisões , Feminino , Infecções por HIV/prevenção & controle , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Malaui , Masculino , Pessoa de Meia-Idade , Autoeficácia , Fatores Socioeconômicos , Zimbábue
7.
Health Educ Behav ; 42(2): 249-56, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25288490

RESUMO

Reducing stigma against people living with HIV is key to encouraging HIV testing, which in turn is an important component in the treatment-as-prevention approach. We analyzed nationally representative survey data of participants aged 15 years and older in Namibia (N = 4,300) to determine whether knowledge about HIV and self-efficacy to protect against sexually transmitted HIV would be independently and jointly associated with stigma against people living with HIV, after controlling for demographics. Findings indicated that having less knowledge and feeling less self-efficacy were associated with greater stigma. Our key interaction hypothesis was also supported: stigma among those with lower self-efficacy to reduce risk of sexually transmitted HIV infection was particularly sensitive to the effects of increased knowledge about HIV. Results highlight the importance of enriching knowledge about HIV transmission modes, prevention strategies, and support services among those with low self-efficacy in order to reduce stigma against people living with HIV, and has useful implications for designing anti-stigma campaigns.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Autoeficácia , Estigma Social , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Namíbia , Fatores Sexuais , Adulto Jovem
8.
J Health Commun ; 20(1): 51-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24870830

RESUMO

Research on the impersonal impact hypothesis suggests that news (especially print) coverage of health and safety risks primarily influences perceptions of risk as a societal issue, and not perceptions of personal risk. The authors propose that the impersonal impact of news-impact primarily on concerns about social-level risks-will mediate effects of news stories on support for public health policies; such effects substantively matter as evidence suggests health policies, in turn, have important effects on protective behaviors and health outcomes. In an experiment using 60 randomly selected violent crime and accident news stories manipulated to contain or not contain reference to alcohol use as a causative factor, the authors find that the effect of stories that mention alcohol as a causative factor on support for alcohol-control policies is mediated by social-level concern and not by personal-level concern. In so doing, the authors provide a theoretical explanation as well as empirical evidence regarding the potential for news coverage-including breaking or episodic news-to influence health-related public policy.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/prevenção & controle , Política de Saúde , Meios de Comunicação de Massa/estatística & dados numéricos , Opinião Pública , Ferimentos e Lesões/etiologia , Acidentes de Trânsito , Adulto , Crime , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição de Risco , Percepção Social , Violência
9.
J Media Psychol ; 25(4): 160-170, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26491487

RESUMO

Prior research shows that discrete emotions, notably anger and fear, can explain effects of news articles on health and alcohol-control policy support. This study advances prior work by coding expressed emotional responses to messages (as opposed to directly manipulated emotions or forced responses), incorporating and controlling for central thoughts, including sadness (a particularly relevant response to tragic stories), and examining concern's mediating role between emotion and policy support. An experiment with a national online adult panel had participants read one of 60 violent crime or accident news stories, each manipulated to mention or withhold alcohol's causal contribution. Multi-group structural equation models suggest that stories not mentioning alcohol had a direct effect on policy support via fear and central thoughts, unmediated by concern. When alcohol was mentioned, sadness and anger affects alcohol-control support through concern. Findings help confirm that emotional responses are key in determining news story effects on public support of health policies.

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