Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Environ Sci Technol ; 58(18): 7802-7813, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38578665

RESUMO

Carbon neutral or negative mining can potentially be achieved by integrating carbon mineralization processes into the mine design, operations, and closure plans. Brucite [Mg(OH)2] is a highly reactive mineral present in some ultramafic mine tailings with the potential to be rapidly carbonated and can contain significant amounts of ferrous iron [Fe(II)] substituted for Mg; however, the influence of this substitution on carbon mineralization reaction products and efficiency has not been thoroughly constrained. To better assess the efficiency of carbon storage in brucite-bearing tailings, we performed carbonation experiments using synthetic Fe(II)-substituted brucite (0, 6, 23, and 44 mol % Fe) slurries in oxic and anoxic conditions with 10% CO2. Additionally, the carbonation process was evaluated using different background electrolytes (NaCl, Na2SO4, and Na4SiO4). Our results indicate that carbonation efficiency decreases with increasing Fe(II) substitution. In oxic conditions, precipitation of ferrihydrite [Fe10IIIO14(OH)2] and layered double hydroxides {e.g., pyroaurite [Mg6Fe2III(OH)16CO3·4H2O]} limited carbonation efficiency. Carbonation in anoxic environments led to the formation of Fe(II)-substituted nesquehonite (MgCO3·3H2O) and dypingite [Mg5(CO3)4(OH)2·âˆ¼5H2O], as well as chukanovite [Fe2IICO3(OH)2] in the case of 23 and 44 mol % Fe(II)-brucite carbonation. Carbonation efficiencies were consistent between chloride- and sulfate-rich solutions but declined in the presence of dissolved Si due to the formation of amorphous SiO2·nH2O and Fe-Mg silicates. Overall, our results indicate that carbonation efficiency and the long-term fate of stored CO2 may depend on the amount of substituted Fe(II) in both feedstock minerals and carbonate products.


Assuntos
Ferro , Ferro/química , Hidróxido de Magnésio/química , Carbono/química , Mineração , Soluções
2.
Environ Res ; 253: 119176, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38768887

RESUMO

This study investigates spatiotemporal dynamics in metal sedimentation in the North American Great Lakes and their underlying biogeochemical controls. Bulk geochemical and isotope analyses of n = 72 surface and core sediment samples show that metal (Cu, Zn, Pb) concentrations and their isotopic compositions vary spatially across oligotrophic to mesotrophic settings, with intra-lake heterogeneity being similar or higher than inter-lake (basin-scale) variability. Concentrations of Cu, Zn, and Pb in sediments from Lake Huron and Lake Erie vary from 5 to 73 mg/kg, 18-580 mg/kg, and 5-168 mg/kg, respectively, but metal enrichment factors were small (<2) across the surface- and core sediments. The isotopic signatures of surface sediment Cu (δ65Cu between -1.19‰ and +0.96‰), Zn (δ66Zn between -0.09‰ and +0.41‰) and Pb (206/207Pb from 1.200 to 1.263) indicate predominantly lithogenic metal sourcing. In addition, temporal trends in sediment cores from Lake Huron and Lake Erie show uniform metal concentrations, minor enrichment, and Zn and Pb isotopic signatures suggestive of negligible in-lake biogeochemical fractionation. In contrast, Cu isotopic signatures and correlation to chlorophyll and macronutrient levels suggest more differentiation from source variability and/or redox-dependent fractionation, likely related to biological scavenging. Our results are used to derive baseline metal sedimentation fluxes and will help optimize water quality management and strategies for reducing metal loads and enrichment in the Great Lakes and beyond.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Poluentes Químicos da Água , Sedimentos Geológicos/química , Sedimentos Geológicos/análise , Lagos/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Isótopos/análise , Great Lakes Region , Metais Pesados/análise
3.
Clin Otolaryngol ; 49(2): 176-184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37915294

RESUMO

OBJECTIVES: Tonsillectomy is the most common operation performed by otolaryngologists in the UK, despite this we have a poor understanding of the post-operative recovery. We aimed to investigate post-operative bleeding and pain following paediatric tonsillectomy using a patient diary. DESIGN: Prospective observational cohort study. SETTING: Multi-centre study involving 12 secondary and tertiary otolaryngology units across the North of England. Patients were recruited from 1st March 2020 to 30th June 2022. Multilevel ordered logistic regression model statistics were performed. PARTICIPANTS: Children (≥4 years, ≤16 years) undergoing tonsillectomy (with or without adenoidectomy) for benign pathology. MAIN OUTCOME MEASURES: Frequency and severity of post-operative bleeding. Intensity and pattern of post-operative pain. RESULTS: In total 297 children were recruited, with 91 (30.6%) diaries eligible for analysis. Post-operative bleeding occurred in 44% of children. Most frequently blood in the saliva was reported (82.9%). Increasing age significantly increased bleeding odds by 17% per year (p = .001). Bleeding frequency decreased with higher surgeon grade (p = .003) and when performing intracapsular coblation tonsillectomy (p = .02) compared with other techniques. Lower age and intracapsular coblation tonsillectomy, against other techniques, significantly reduced rates of pain post-operatively (p < .0001 and p = .0008). CONCLUSION: A high level of low-level post-operative bleeding was observed. Pain scores remained high for 5 days post-operatively then gradually reduce to normal by day 13. Intracapsular coblation tonsillectomy appears to be superior to all other techniques in terms of reducing post-operative bleeding and pain. These findings should be used to guide patients in the consent process to inform them of the expected nature of post-surgical recovery.


Assuntos
Tonsilectomia , Criança , Humanos , Tonsilectomia/efeitos adversos , Tonsilectomia/métodos , Estudos de Coortes , Estudos Prospectivos , Adenoidectomia/efeitos adversos , Adenoidectomia/métodos , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/etiologia , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia
4.
Arch Orthop Trauma Surg ; 142(7): 1547-1556, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33813616

RESUMO

INTRODUCTION: This study aimed to investigate potential factors, including delay to surgical stabilisation, affecting mortality in older patients sustaining pelvic or acetabular (PA) fractures. MATERIALS AND METHODS: A retrospective review of the Trauma Audit and Research Network (TARN) database was performed to identify older patients (aged 65 and over) sustaining PA fractures treated surgically in a UK Major Trauma Centre (MTC) between 2015 and 2019. Chi-squared and Fisher tests were used to compare 1-year mortality rates following operative intervention between patients treated within 72 h and after 72 h. Kaplan-Meier curves were used to visualise survival probability; significant predictors of survival were found using Cox proportional hazard models. RESULTS: Of 564 older patients with PA fractures, 70 met the inclusion criteria. The mean age was 76.1 years. The overall 1-year mortality rate was 20%. When patients were grouped by time to surgery (fracture fixation within or greater than 72 h), there was no statistically significant difference in 1-year mortality. Patients whose surgery was delayed more than 72 h were more likely to have longer hospital stays (p = 0.002) or to have suffered from polytrauma (p = 0.025). Age, Charlson Co-morbidities Index (CCI) and pre-op mobility status were associated with statistically significant differences in overall mortality. The same factors were associated with a significantly increased hazard of death in the multivariate Cox proportional hazards model. Patient gender, mechanism of injury, Injury Severity Score (ISS) > 15 and head injury were not significant predictors of mortality. CONCLUSION: Surgical intervention within 72 h of injury did not result in decreased mortality in older patients with PA fractures. The 1-year mortality rate between older PA fractures and hip fractures was comparable. Consideration should be given to a combined multidisciplinary approach between orthogeriatric and expert PA surgeons for these patients.


Assuntos
Fraturas Ósseas , Fraturas do Quadril , Traumatismo Múltiplo , Lesões do Pescoço , Fraturas da Coluna Vertebral , Idoso , Fixação de Fratura , Fraturas Ósseas/cirurgia , Humanos , Escala de Gravidade do Ferimento , Estudos Retrospectivos
5.
Clin Otolaryngol ; 47(2): 279-286, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34213821

RESUMO

OBJECTIVES: A dose of 5 mg/kg lidocaine is considered appropriate for paediatric airway topicalisation. Existing literature suggests that younger children are susceptible to toxic lidocaine plasma levels and achieve this at a faster rate. MAIN OUTCOME MEASURES: The primary outcome of this study was to ascertain peak plasma lidocaine levels after topicalisation for airway endoscopy. Secondary endpoints included: time to peak lidocaine plasma levels, signs of lidocaine toxicity (restricted to ECG changes or seizures when under anaesthesia) and clinical adverse events of laryngospasm, coughing or desaturation during the procedure. SETTING: Data were collected prospectively over 18 months at Royal Manchester Children's Hospital. PARTICIPANTS: Children aged 0-8 years undergoing elective diagnostic or therapeutic airway endoscopy were included within the study. DESIGN: Standardised 2% lidocaine was used for airway topicalisation. Dose varied depending upon the practitioner's usual practice. Venous bloodsampling occurred at 5, 10, 15 and 20 min post-administration and plasma lidocaine levels (ng/ml) were analysed. RESULTS: A significant relationship exists between higher peak plasma levels and ages <18 months (p = .00973). Strong linear correlation exists between body weight and age for our cohort (r = .88). Higher peak plasma lidocaine levels occur with total dose volumes between 2 and 3 mls of 2% lidocaine local anaesthetic (p = .03) compared with <2 ml total dose volumes. Data suggest a potential relationship of lower body weights achieving higher peak plasma levels (p = .0516). Reduced interquartile variation of peak plasma lidocaine levels exists when lidocaine dosing is <5 mg/kg. CONCLUSIONS: Age and total dose volume of topicalised lidocaine have a significant relationship with plasma lidocaine levels. A dose of 5 mg/kg topicalised lidocaine for paediatric airway endoscopy is safe and provides good operating conditions. Lower patient body weights trend towards higher peak lidocaine plasma concentrations and require further investigation.


Assuntos
Endoscopia/métodos , Laringoscopia/métodos , Lidocaína/administração & dosagem , Lidocaína/sangue , Administração Tópica , Anestésicos Locais/administração & dosagem , Anestésicos Locais/sangue , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Estudos Prospectivos
6.
Child Youth Serv Rev ; 1322022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37745773

RESUMO

Objectives: We examined the prevalence of sexting, related motivations, demographics, and association with behavioral health problems among justice-involved adolescents. Hypotheses: We hypothesized positive associations between sexting and sexual risk, substance use, delinquency, and mental health problems. Methods: Participants were 307 community-supervised justice-involved adolescents with a first-time offense (Mage =14.50 years, 44.6% female) and their caregivers. Adolescents answered questions on technology use and sexting by sending, receiving, or forwarding sexually suggestive text messages and images (pictures or videos). They also completed measures of recent (past 4-month) sexual activity, unprotected sex, cigarette, alcohol, marijuana, and other drug use, and delinquency; current trauma symptoms, internalizing problems, and adaptive functioning. Results: Prevalence of sexting were 37.7% (lifetime overall; 17.0% sent texts; 17.4% sent images) and 29.5% (past-year overall; 12.8% sent texts; 13.6% sent images). Sexts were commonly sent as presents to partners, in response to sexts received, or to have fun. "Sexters" were older than "non-sexters" and more likely to identify as lesbian, gay, bisexual, or questioning. Past-year sexting was significantly associated with recent sexual activity; unprotected sex; alcohol use and days of use; marijuana and other drug use; delinquency and variety of delinquent acts; and elevated trauma symptoms and internalizing problems. Conclusions: Sexting is prevalent among adolescents with a first-time offense and co-occurs with multiple behavioral health needs. Intervention for this population may be informed by routinely assessing sexting in community settings. Familiarity with local reporting laws could help clinicians navigate the legal implications of sexting among adolescents with existing justice-system involvement.

7.
J Med Internet Res ; 22(4): e16370, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-32352388

RESUMO

BACKGROUND: Caregiver involvement is critical for supporting positive behavioral health and legal outcomes for justice-involved youth; however, recruiting this population into clinical research studies and engaging them in treatment remain challenging. Technology-based approaches are a promising, yet understudied avenue for recruiting and intervening with caregivers of justice-involved youth. OBJECTIVE: This mixed methods study aimed to assess the feasibility of recruiting caregivers of justice-involved youth using social media into clinical research and to understand caregivers' perceptions of the acceptability of digital health interventions. METHODS: Caregivers of justice-involved youth were recruited through paid Facebook advertisements to participate in a Web-based survey. Advertisement design was determined using Facebook A/B split testing, and the advertisement with the lowest cost per link click was used for the primary advertisement campaign. Survey participants were offered the option to participate in a follow-up qualitative phone interview focused on the perceived feasibility and acceptability of digital health interventions. RESULTS: Facebook advertisements were successful in quickly recruiting a diverse set of caregivers (80/153, 52.3% female; mean age 43 years, SD 7; 76/168, 45.2% black, 34/168, 20.2% white, and 28/168, 16.7% Latinx; and 97/156, 62.2% biological parents); cost per click was US $0.53, and conversion rate was 11.5%. Survey participants used multiple social media platforms; 60.1% (101/168) of the participants indicated they would participate in a digital health intervention for caregivers of justice-involved youth. Survey respondents' most preferred intervention was supportive and motivational parenting messages via SMS text message. Of the survey respondents, 18 completed a phone interview (12/18, 67% female; mean age 45 years, SD 10; 10/18, 56% black, 7/18, 39% white, and 1/18, 6% Latinx; and 16/18, 89% biological parents). Interview participant responses suggested digital health interventions are acceptable, but they expressed both likes (eg, alleviates barriers to treatment access) and concerns (eg, privacy); their most preferred intervention was video-based family therapy. CONCLUSIONS: Recruiting and intervening with caregivers of justice-involved youth through social media and other digital health approaches may be a feasible and acceptable approach to overcoming barriers to accessing traditional in-person behavioral health care.


Assuntos
Justiça Social/normas , Mídias Sociais/estatística & dados numéricos , Adulto , Cuidadores , Estudos de Viabilidade , Feminino , Humanos , Masculino , Telemedicina
8.
Subst Use Misuse ; 55(4): 572-581, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31760909

RESUMO

Background: Justice-involved youth are at risk to become cigarette smokers as they age, leading to a variety of poor health outcomes. However, little is known about cigarette use among justice-involved youth, especially youth supervised in the community where there is ample opportunity to smoke. Objective: This study investigates the prevalence of cigarette smoking and the associations between cigarette smoking, emotional and behavioral functioning, and other substance use among a sample of first-time offending court-involved, non-incarcerated (FTO-CINI) youth. Methods: Youth were recruited from a family court in the Northeast (N = 423). Substance use was self-reported using the Adolescent Risk Behavior Assessment (ARBA). Emotional and behavioral functioning was measured using the Behavior Assessment Schedule for Children-Second Edition (BASC-2), the Affect Dysregulation Scale (ADS), National Stressful Events Survey PTSD Short Scale (NSESSS), and the National Survey of Self-Reported Delinquency (NYS-SRD). Results: About 9.9% of FTO-CINI youth had smoked cigarettes in the past 30 days. Compared with FTO-CINI youth who had not smoked recently, recent smokers endorsed more emotional and behavioral symptoms, such as school problems (p < .001), internalizing problems (p = .012), inattention/hyperactivity (p = .020), affect dysregulation (p = .044), PTSD symptoms (p = .006), and delinquent behavior (p < .001). Recent smokers were also more likely to use alcohol (OR = 5.61, p < .001), marijuana (OR = 11.27, p < .001), and other drugs (OR = 5.00, p < .001). Conclusions: Recent smoking was higher among FTO-CINI youth than youth in the general population. Findings underscore the need to incorporate nicotine into existing substance use prevention interventions for this population, who are at high risk to initiate cigarette use as they age.


Assuntos
Fumar Cigarros , Delinquência Juvenil , Saúde Mental , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Criança , Fumar Cigarros/epidemiologia , Feminino , Humanos , Masculino , New England , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
9.
J Cell Sci ; 130(19): 3234-3247, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28775154

RESUMO

Galectins are a family of lectin binding proteins expressed both intracellularly and extracellularly. Galectin-3 (Gal-3, also known as LGALS3) is expressed at the cell surface; however, Gal-3 lacks a signal sequence, and the mechanism of Gal-3 transport to the cell surface remains poorly understood. Here, using a genome-wide CRISPR/Cas9 forward genetic screen for regulators of Gal-3 cell surface localization, we identified genes encoding glycoproteins, enzymes involved in N-linked glycosylation, regulators of ER-Golgi trafficking and proteins involved in immunity. The results of this screening approach led us to address the controversial role of N-linked glycosylation in the transport of Gal-3 to the cell surface. We find that N-linked glycoprotein maturation is not required for Gal-3 transport from the cytosol to the extracellular space, but is important for cell surface binding. Additionally, secreted Gal-3 is predominantly free and not packaged into extracellular vesicles. These data support a secretion pathway independent of N-linked glycoproteins and extracellular vesicles.


Assuntos
Retículo Endoplasmático/metabolismo , Galectina 3/metabolismo , Complexo de Golgi/metabolismo , Proteínas Sanguíneas , Sistemas CRISPR-Cas , Retículo Endoplasmático/genética , Galectina 3/genética , Galectinas , Estudo de Associação Genômica Ampla , Glicosilação , Complexo de Golgi/genética , Células HeLa , Humanos , Transporte Proteico/fisiologia
10.
Curr HIV/AIDS Rep ; 16(1): 37-47, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30734906

RESUMO

PURPOSE OF REVIEW: This review discusses recent advances in research on the intersection of HIV prevention and substance use among youth involved with the justice system. We discuss current themes of recent findings and provide guidance for researchers, policymakers, and clinicians on the next steps in advancing work in this nascent area. RECENT FINDINGS: Of the 46 studies that measured HIV risk and substance use among justice-involved youth, 56% were cross-sectional designs, 22% were intervention trials, and 22% were longitudinal designs. Cross-sectional studies suggested that substance use is highly associated with HIV risk behaviors. Longitudinal analyses underscored the importance of understanding contextual risk factors, such as trauma and violence. Intervention trials demonstrated improved scientific rigor of behavioral approaches. Despite recent advances, research in this field remains limited. Future directions include longer follow-up periods, consideration of biomedical HIV-prevention interventions, and a focus on dissemination and implementation science of efficacious interventions.


Assuntos
Infecções por HIV/terapia , Delinquência Juvenil/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/terapia , Adolescente , Estudos Transversais , Feminino , Humanos , Masculino , Fatores de Risco , Adulto Jovem
11.
Environ Sci Technol ; 53(6): 3225-3237, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30786208

RESUMO

The stability and longevity of carbonate minerals make them an ideal sink for surplus atmospheric carbon dioxide. Biogenic magnesium carbonate mineral precipitation from the magnesium-rich tailings generated by many mining operations could offset net mining greenhouse gas emissions, while simultaneously giving value to mine waste products. In this investigation, cyanobacteria in a wetland bioreactor enabled the precipitation of magnesite (MgCO3), hydromagnesite [Mg5(CO3)4(OH)2·4H2O], and dypingite [Mg5(CO3)4(OH)2·5H2O] from a synthetic wastewater comparable in chemistry to what is produced by acid leaching of ultramafic mine tailings. These precipitates occurred as micrometer-scale mineral grains and microcrystalline carbonate coatings that entombed filamentous cyanobacteria. This provides the first laboratory demonstration of low temperature, biogenic magnesite precipitation for carbon sequestration purposes. These findings demonstrate the importance of extracellular polymeric substances in microbially enabled carbonate mineral nucleation. Fluid composition was monitored to determine carbon sequestration rates. The results demonstrate that up to 238 t of CO2 could be stored per hectare of wetland/year if this method of carbon dioxide sequestration was implemented at an ultramafic mine tailing storage facility. The abundance of tailings available for carbonation and the anticipated global implementation of carbon pricing make this method of mineral carbonation worth further investigation.


Assuntos
Sequestro de Carbono , Magnésio , Carbono , Dióxido de Carbono , Carbonatos , Minerais
12.
J Offender Rehabil ; 57(7): 459-480, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31190722

RESUMO

Supportive social networks are key to the successful transition to young adulthood. Yet, we know little about networks of delinquent youth, a population at risk for disrupted social connections. This study describes the structure and function of social support networks among delinquent youth eight years after detention; median age 24 years. Nearly one-fifth of participants had no one that they could count on, and one-third had only one person in their support network. Participants tended to have very dense networks composed almost entirely of family. Findings underscore the importance of expanding social supports for delinquent youth as they age.

13.
Child Youth Serv Rev ; 83: 201-208, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34276117

RESUMO

Multiple assessment studies demonstrate that juvenile offenders are at increased risk for contracting HIV and other STIs relative to their non-offending counterparts. Such data are used to support the implementation of adolescent HIV prevention interventions within the juvenile justice system. Despite the compelling data related to high rates of unprotected sexual activity, pregnancy, STIs, substance use and psychiatric symptoms, there are very few empirically supported HIV prevention interventions for this adolescent subgroup. Using our experience conducting HIV prevention research studies with court-involved, non-incarcerated (CINI) youth we identify salient and unique challenges to consider when conducting HIV prevention intervention research with this population. Obstacles to consider include lack of "buy-in" and engagement from justice staff and families about the need for youth sexual health promotion and HIV prevention services and logistical barriers (time, transportation, space) related to conducting intervention research with a community-based sample of justice-involved youth. We consider these various challenges and provide recommendations for researchers on how to overcome barriers to continue to develop evidence-based HIV prevention services for communities of youth in need.

14.
Am J Public Health ; 106(5): 872-80, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26985602

RESUMO

OBJECTIVES: To examine sex and racial/ethnic differences in the prevalence of 9 substance-use disorders (SUDs)--alcohol, marijuana, cocaine, hallucinogen or PCP, opiate, amphetamine, inhalant, sedative, and unspecified drug--in youths during the 12 years after detention. METHODS: We used data from the Northwestern Juvenile Project, a prospective longitudinal study of 1829 youths randomly sampled from detention in Chicago, Illinois, starting in 1995 and reinterviewed up to 9 times in the community or correctional facilities through 2011. Independent interviewers assessed SUDs with Diagnostic Interview Schedule for Children 2.3 (baseline) and Diagnostic Interview Schedule version IV (follow-ups). RESULTS: By median age 28 years, 91.3% of males and 78.5% of females had ever had an SUD. At most follow-ups, males had greater odds of alcohol- and marijuana-use disorders. Drug-use disorders were most prevalent among non-Hispanic Whites, followed by Hispanics, then African Americans (e.g., compared with African Americans, non-Hispanic Whites had 32.1 times the odds of cocaine-use disorder [95% confidence interval = 13.8, 74.7]). CONCLUSIONS: After detention, SUDs differed markedly by sex, race/ethnicity, and substance abused, and, contrary to stereotypes, did not disproportionately affect African Americans. Services to treat substance abuse--during incarceration and after release--would reach many people in need, and address health disparities in a highly vulnerable population.


Assuntos
Delinquência Juvenil/estatística & dados numéricos , Prisioneiros/estatística & dados numéricos , Transtornos Relacionados ao Uso de Substâncias/etnologia , Adolescente , Adulto , Negro ou Afro-Americano , Transtornos Relacionados ao Uso de Álcool/etnologia , Chicago/epidemiologia , Criança , Feminino , Hispânico ou Latino , Humanos , Estudos Longitudinais , Masculino , Prevalência , Estudos Prospectivos , Fatores Sexuais , Transtornos Relacionados ao Uso de Substâncias/classificação , Fatores de Tempo , População Branca , Adulto Jovem
15.
Environ Sci Technol ; 50(5): 2610-8, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26829491

RESUMO

Carbonic anhydrase (CA) enzymes have gained considerable attention for their potential use in carbon dioxide (CO2) capture technologies because they are able to catalyze rapidly the interconversion of aqueous CO2 and bicarbonate. However, there are challenges for widespread implementation including the need to develop mineralization process routes for permanent carbon storage. Mineral carbonation of highly reactive feedstocks may be limited by the supply rate of CO2. This rate limitation can be directly addressed by incorporating enzyme-catalyzed CO2 hydration. This study examined the effects of bovine carbonic anhydrase (BCA) and CO2-rich gas streams on the carbonation rate of brucite [Mg(OH)2], a highly reactive mineral. Alkaline brucite slurries were amended with BCA and supplied with 10% CO2 gas while aqueous chemistry and solids were monitored throughout the experiments (hours to days). In comparison to controls, brucite carbonation using BCA was accelerated by up to 240%. Nesquehonite [MgCO3·3H2O] precipitation limited the accumulation of hydrated CO2 species, apparently preventing BCA from catalyzing the dehydration reaction. Geochemical models reproduce observed reaction progress in all experiments, revealing a linear correlation between CO2 uptake and carbonation rate. Data demonstrates that carbonation in BCA-amended reactors remained limited by CO2 supply, implying further acceleration is possible.


Assuntos
Carbonatos/metabolismo , Anidrases Carbônicas/metabolismo , Minerais/metabolismo , Animais , Dióxido de Carbono/metabolismo , Sequestro de Carbono , Bovinos , Concentração de Íons de Hidrogênio , Hidróxido de Magnésio/química , Microscopia Eletrônica de Varredura , Modelos Teóricos , Água/química
16.
Horm Behav ; 67: 48-53, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25479193

RESUMO

The site(s) of action that control meal size and intermeal interval (IMI) length by cholecystokinin-58 (CCK-58), the only detectable endocrine form of CCK in the rat, are not known. To test the hypothesis that the gastrointestinal tract may contain such sites, we infused low doses of CCK-58 (0.01, 0.05, 0.15 and 0.25nmol/kg) into the celiac artery (CA, supplying stomach and upper duodenum), the cranial mesenteric artery (CMA, supplying small and most of the large intestines), the femoral artery (FA, control) and the portal vein (PV, draining the gastrointestinal tract) prior to the onset of the dark cycle in freely fed male rats. We measured the first meal size (chow), second meal size, IMI and satiety ratio (SR, IMI/meal size). We found that (1) all doses of CCK-58 given in the CA and the highest dose given in the CMA reduced the first meal size, (2) all doses of CCK-58 given in the CA reduced the second meal size, (3) a CCK-58 dose of 0.15nmol/kg given in the CA and 0.15 and 0.25nmol/kg given in the CMA prolonged the IMI, (4) CCK-58 (0.05, 0.15, 0.25nmol/kg) given in the CA and 0.25nmol/kg given in the CMA increased the SR, and (5) CCK-58 given in the FA and PV had no effect on the meal size or intermeal interval. These results support our hypothesis that the gastrointestinal tract contains sites of action that regulate meal size and IMI length via CCK-58. The stomach and upper duodenum may contain sites regulating meal size, whereas the small intestine and part of the large intestine may contain sites regulating the IMI.


Assuntos
Artéria Celíaca/metabolismo , Colagogos e Coleréticos/farmacologia , Colecistocinina/farmacologia , Comportamento Alimentar/fisiologia , Artéria Mesentérica Superior/metabolismo , Resposta de Saciedade/fisiologia , Animais , Colagogos e Coleréticos/administração & dosagem , Colecistocinina/administração & dosagem , Artéria Femoral/metabolismo , Masculino , Veia Porta/metabolismo , Ratos , Ratos Sprague-Dawley , Resposta de Saciedade/efeitos dos fármacos
17.
J Cosmet Laser Ther ; 17(4): 170-6, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25594129

RESUMO

The treatment of acne vulgaris poses a challenge to the dermatologist, and the disease causes emotional anxiety for the patient. The treatment of acne vulgaris may be well-suited to home-use applications, where sufferers may be too embarrassed to seek medical treatment. This randomized controlled study is designed to quantify the effectiveness of using a blue light device in a therapy combined with proprietary creams, in the investigation of a self-treatment regimen. A total of 41 adults with mild-to-moderate facial inflammatory acne were recruited. The subjects were randomly assigned to combination blue light therapy (n = 26) or control (n = 15). Photography was used for qualitative assessment of lesion counts, at weeks 1, 2, 4, 8, and 12. All subjects in the treatment cohort achieved a reduction in their inflammatory lesion counts after 12 weeks. The mean inflammatory lesion counts reduced by 50.02% in the treatment cohort, and increased by 2.45% in the control cohort. The reduction in inflammatory lesions was typically observable at week-3, and maximal between weeks 8 and 12. The treatment is free of pain and side-effects. The blue light device offers a valuable alternative to antibiotics and potentially irritating topical treatments. Blue light phototherapy, using a narrow-band LED light source, appears to be a safe and effective additional therapy for mild to moderate acne.


Assuntos
Acne Vulgar/terapia , Ceratolíticos/uso terapêutico , Fototerapia/instrumentação , Adolescente , Adulto , Terapia Combinada , Técnicas Cosméticas , Método Duplo-Cego , Feminino , Glicolatos/uso terapêutico , Humanos , Ceratolíticos/administração & dosagem , Ácido Láctico/uso terapêutico , Masculino , Pessoa de Meia-Idade , Ácido Salicílico/uso terapêutico , Índice de Gravidade de Doença , Adulto Jovem
18.
Environ Sci Technol ; 48(16): 9142-51, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25072950

RESUMO

A cyanobacteria dominated consortium collected from an alkaline wetland located near Atlin, British Columbia, Canada accelerated the precipitation of platy hydromagnesite [Mg5(CO3)4(OH)2·4H2O] in a linear flow-through experimental model wetland. The concentration of magnesium decreased rapidly within 2 m of the inflow point of the 10-m-long (∼1.5 m(2)) bioreactor. The change in water chemistry was monitored over two months along the length of the channel. Carbonate mineralization was associated with extra-cellular polymeric substances in the nutrient-rich upstream portion of the bioreactor, while the lower part of the system, which lacked essential nutrients, did not exhibit any hydromagnesite precipitation. A mass balance calculation using the water chemistry data produced a carbon sequestration rate of 33.34 t of C/ha per year. Amendment of the nutrient deficiency would intuitively allow for increased carbonation activity. Optimization of this process will have application as a sustainable mining practice by mediating magnesium carbonate precipitation in ultramafic mine tailings storage facilities.


Assuntos
Reatores Biológicos , Sequestro de Carbono , Cianobactérias/metabolismo , Magnésio/metabolismo , Colúmbia Britânica , Resíduos Industriais , Mineração , Fotossíntese , Água/química
19.
J Adolesc Health ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38912979

RESUMO

PURPOSE: Investigate if the type of substance use disorder (SUD) in adolescence predicts SUDs in adulthood and examine sex and racial/ethnic differences in the persistence of SUDs. METHODS: Data are from the Northwestern Juvenile Project, a 15-year longitudinal study of 1829 youth randomly sampled from detention in Chicago, IL (1995-1998). Interviewers assessed SUDs using structured diagnostic interviews. RESULTS: Compared with females without an SUD at detention, females with cannabis alone, comorbid alcohol and cannabis, or SUDs other than alcohol and cannabis at detention had higher odds of having an SUD 5 years later (25%, 32%, and 36% vs. 15%, adjusted odds ratio [AOR] = 1.94, 95% confidence interval [CI] 1.11-3.40; AOR = 2.76, 95% CI 1.58-4.83; AOR = 3.46, 95% CI 1.56-7.66, respectively). Males and females with SUDs other than alcohol and cannabis at detention had greater odds of having an SUD 15 years later, compared with those without an SUD at detention (males: 36% vs. 14%, AOR = 2.98, 95% CI 1.14-7.83; females: 29% vs. 8%, AOR = 4.77, 95% CI 1.85-12.30). Among youth with an SUD at detention, males were more likely than females to have an SUD 15 years later (AOR = 1.84, 95% CI 1.03-3.29); non-Hispanic White and Hispanic males were more likely to persist than Black males (AOR = 3.32, 95% CI 1.50-7.35; AOR = 2.32, 95% CI 1.04-5.18, respectively). DISCUSSION: The type of SUD during adolescence matters. Youth with SUDs such as cocaine and opioids fared the worst. Healthcare providers must collaborate with correctional officials to increase service provision.

20.
Environ Toxicol Chem ; 43(5): 999-1011, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38415806

RESUMO

Microplastic contamination is ubiquitous across the globe, even in remote locations. Still, the sources and pathways of microplastics to such locations are largely unknown. To investigate microplastic contamination in a semi-remote location, we measured microplastic concentrations in nine oligotrophic lakes within and around the International Institute for Sustainable Development-Experimental Lakes Area in northwestern Ontario, Canada. Our first objective was to establish ambient concentrations of microplastics in bottom sediments, surface water, and atmospheric deposition in semi-remote boreal lakes. Across all lakes, mean shallow and deep sediment microplastic concentrations, near-surface water microplastic concentrations from in situ filtering, and dry atmospheric microplastic deposition rates were 551 ± 354 particles kg-1, 177 ± 103 particles kg-1, 0.2 ± 0.3 particles L-1, and 0.4 ± 0.2 particles m-2 day-1, respectively. Our second objective was to investigate whether microplastic contamination of these lakes is driven by point sources including local runoff and direct anthropogenic inputs or nonpoint sources such as atmospheric deposition. Lakes were selected based on three levels of anthropogenic activity-low, medium, and high-though activity levels were minimal across all study lakes compared with highly populated areas. Whereas a positive correlation would indicate that point sources were a likely pathway, we observed no relationship between the level of anthropogenic activity and microplastic contamination of surface water. Moreover, the composition of microplastics in surface water and atmospheric deposition were similar, comprising mostly polyester and acrylic fibers. Together, these results suggest that atmospheric deposition may be the main pathway of microplastics to these remote boreal lakes. Environ Toxicol Chem 2024;43:999-1011. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.


Assuntos
Monitoramento Ambiental , Lagos , Microplásticos , Poluentes Químicos da Água , Lagos/química , Microplásticos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Ontário , Sedimentos Geológicos/química
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa