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1.
Harm Reduct J ; 20(1): 68, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221542

RESUMO

BACKGROUND: Brass screens are considered an essential part of the safer drug smoking/inhalation supplies and are widely distributed by harm reduction programs in Canada. However, the use of commercially available steel wools as screens for smoking crack cocaine remains a common practice among people who smoke drugs in Canada. Use of these steel wool materials is associated with different adverse effects on health. This study aims to determine what changes folding and heating have on several filter materials, including brass screens and commercially available steel wool products, and examine the implications of these changes on health of people who smoke drugs. METHODS: This study investigated the microscopic differences, studied by optical and scanning electron microscopy, between four screen and four steel wool filter materials used in a simulated drug consumption process. New materials were manipulated, compacted into its own Pyrex® straight stem using a push stick and then heated with a butane lighter simulating a common method in preparing drugs for consumption. The materials were studied in the as-received (new), as-pressed (compressed and inserted into the stem tube but without heating) and as-heated (compressed and inserted into the stem tube and heated with a butane lighter) conditions. RESULTS: The steel wool materials with the smallest wire thicknesses were found to be the easiest to prepare for pipe use, but degrade significantly during shaping and heating, making them wholly unsuitable as a safe filter material. In contrast the brass and stainless steel screen materials remain mostly unchanged by the simulated drug consumption process. After the stainless steel pellet screen, the Brass Impact 2.0 screen material had the best characteristics of the materials tested due to its mesh wire diameter, pitch, alloy choice and its pre-strained state. CONCLUSION: Commonly used steel wool alternatives degrade during the handling and stem insertion, and heating the screens in the stem. Debris is generated by wool deformation on insertion and after heating that easily separates from the screen and can be inhaled during drug consumption. The brass and stainless steel screen materials are safer to use as they remain mostly stable during the simulated drug consumption process.


Assuntos
Aço Inoxidável , Aço , Humanos , Butanos , Fumar
2.
J Appl Clin Med Phys ; 24(9): e14054, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37287131

RESUMO

PURPOSE: To compare the superficial dose when using brass mesh bolus (BMB), no bolus, or 3 mm tissue-equivalent bolus with a pseudo-flash volumetric modulated arc therapy (VMAT) breast treatment planning technique. METHODS: Two different beam arrangements for right-sided irradiation and one beam arrangement for bilateral irradiation were planned on an inhomogeneous thorax phantom in accordance with our clinical practice for VMAT postmastectomy radiotherapy (PMRT). Plans were optimized using pseudo-flash and representative critical organ optimization structures were used to shape the dose. Plans were delivered without bolus, with 3 mm tissue-equivalent bolus (TEB), or with one-layer BMB. Optically stimulated luminescence dosimeter (OSLD) and radiochromic film measurements were taken and analyzed to determine the superficial dose in each case and the relative enhancement from the no bolus delivery. RESULTS: Superficial dose measured with OSLDs was found to be 76.4 ± 4.5%, 103.0 ± 6.1%, and 98.1 ± 5.8% of prescription for no physical bolus (NB), TEB, and BMB, respectively. Superficial dose was observed to increase from lateral to medial points when measured with film. However, the relative increase in superficial dose from NB was consistent across the profile with an increase of 43 ± 2.1% and 34 ± 3.3% of prescription for TEB and BMB, respectively. The results are in good agreement with expectations from the literature and the experience with tangential radiotherapy. CONCLUSION: Three millimeter TEB and one-layer BMB were shown to provide similar enhancement to the superficial dose compared to delivery without bolus. BMB, which does not significantly affect dose at depth and is more conformal to the patient surface, is an acceptable alternative to 3 mm TEB for chest wall PMRT patients treated with pseudo-flash PMRT.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Parede Torácica , Humanos , Feminino , Radioterapia de Intensidade Modulada/métodos , Parede Torácica/efeitos da radiação , Neoplasias da Mama/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Mastectomia/métodos
3.
Clin Oral Investig ; 27(7): 3961-3972, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37071219

RESUMO

OBJECTIVES: The purpose of this study was to develop a novel Bonwill⁃Hawley method (Bonwill⁃Hawley arch form based on CBCT image) for the assessment of dental crowding, and to investigate and compare the accuracy and eligibility with the conventional brass wire and caliper methods under different crowding conditions. MATERIAL AND METHODS: Sixty patients with the pair of plaster casts and CBCT data were collected. All the casts were marked and transformed into digital models using iTero scanner, and imported into OrthoCAD software to measure the required space. Using the conventional brass wire (M1) and caliper methods (M2), the available space and dental crowding were measured and calculated basing on digital models, respectively. Correspondingly, the axial planes in the level of dental arches were oriented and captured from the CBCT images to draw the Bonwill⁃Hawley arch forms (M3), which were used to measure and calculate the available space and dental crowding. For each method, intra and inter-examiner reliabilities were evaluated with intra-class correlation coefficients (ICCs). Wilcoxon test and Kruskal-Wallis test were performed for statistically analyzing the discrepancy among different groups. RESULTS: Both intra- and inter-examiner reliability were generally excellent for all parameters obtained by the three methods, except for the dental crowding measured using M1(ICC: 0.473/0.261). The dental crowding measured using M2 were significantly increased in mild, moderate and severe-crowding groups compared with M1. However, no significant difference was detected between M1 and M3 in severe-crowding group (maxilla, p = 0.108 > 0.05; mandible, p = 0.074 > 0.05). With the deterioration of crowding condition, the discrepancy of dental crowding between M1 and M2, or M1 and M3 were significantly decreased (maxilla, M2-M1, mild VS serve, p = 0.003 < 0.05; maxilla, M3-M1, mild VS serve, p = 0.003 < 0.05; mandible, M2-M1, mild VS serve, p = 0.000 < 0.001; mandible, M3-M1, mild VS serve, p = 0.043 < 0.05). CONCLUSION: Dental crowding measured using the novel Bonwill⁃Hawley method was relatively greater than the caliper method, but not exceeding the brass wire method, which wound gradually come close to the brass wire method with the deterioration of crowding condition. CLINICAL RELEVANCE: The Bonwill⁃Hawley method basing on CBCT image proved to be a reliable and acceptable choice for orthodontists to analyze the dental crowding.


Assuntos
Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Reprodutibilidade dos Testes , Cobre , Zinco , Mandíbula , Maxila , Arco Dental/diagnóstico por imagem , Imageamento Tridimensional/métodos
4.
Molecules ; 28(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37764285

RESUMO

By taking advantage of typical dealloying and subsequent aging methods, a novel homogeneous porous brass with a micro/nano hierarchical structure was prepared without any chemical modification. The treatment of commercial brass with hot concentrated HCl solution caused preferential etching of Zn from Cu62Zn38 alloy foil, leaving a microporous skeleton with an average tortuous channel size of 1.6 µm for liquid transfer. After storage in the atmosphere for 7 days, the wettability of the dealloyed brass changed from superhydrophilic to superhydrophobic with a contact angle > 156° and sliding angle < 7°. The aging treatment enhanced the hydrophobicity of the brass by the formation of Cu2O on the surface. By virtue of the opposite wettability to water and oil, the aged brass separated surfactant-stabilized water-in-oil emulsions with separation efficiency of over 99.4% and permeate flux of about 851 L·m-2·h-1 even after recycling for 60 times. After 10 times of tape peeling or sandpaper abrasion, the aged brass maintained its superhydrophobicity, indicating its excellent mechanical stability. Moreover, the aged brass still retained its superhydrophobicity after exposure to high temperatures or corrosive solutions, displaying high resistance to extreme environments. The reason may be that the bicontinuous porous structure throughout the whole foil endows stable mechanical properties to tolerate extreme environments. This method should have a promising future in expanding the applications of alloys.

5.
Molecules ; 27(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36235087

RESUMO

In this study, the inhibitive performance of pyridine-2-thiol added to a corrosive solution was investigated for brass using potentiodynamic polarization, electrochemical impedance spectroscopy, and X-ray photoelectron spectroscopy. Electrochemical experiments were performed with different inhibitor concentrations in 0.5 M H2SO4 as the corrosive medium. For potentiodynamic polarization, icorr values decreased significantly for the inhibited solutions in contrast with the uninhibited solution. Pyridine-2-thiol had an optimum inhibition concentration of 0.25 mM, giving an icorr value of 1.8 µA/cm2 compared to 26 µA/cm2 for the blank solution. EIS data indicated that Rp and Rct values increased substantially after the addition of the corrosion inhibitor and corrosion inhibition efficiencies of more than 85% was achieved for the majority of the inhibited solutions. Scanning electron microscopy showed defect free and less scale formation for the inhibited surface but the bare brass surface had larger amounts of scale formation. X-ray photoelectron spectroscopy and UV-vis spectroscopy was used to investigate surface chemical composition and inhibitor structural changes over time.


Assuntos
Cáusticos , Cobre/química , Corrosão , Piridinas , Compostos de Sulfidrila , Zinco
6.
Stat Med ; 40(7): 1593-1638, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33586227

RESUMO

The Sustainable Development Goals call for a total reduction of preventable child mortality before 2030. Further, the goals state the desirability to have subnational mortality estimates. Estimates at this level are required for health interventions at the subnational level. In a low and middle income countries context, the data on mortality typically consist of household surveys, which are carried out with a stratified, cluster design, and census microsamples. Most household surveys collect full birth history (FBH) data on birth and death dates of a mother's children, but censuses collect summary birth history (SBH) data which consist only of the number of children born and the number that died. In previous work, direct (survey-weighted) estimates with associated variances were derived from FBH data and smoothed in space and time. Unfortunately, the FBH data from household surveys are usually not sufficiently abundant to obtain yearly estimates at the Admin-2 level (at which interventions are often made). In this paper we describe four extensions to previous work: (i) combining SBH data with FBH data, (ii) modeling on a yearly scale, to combine data on a yearly scale with data at coarser time scales, (iii) adjusting direct estimates in Admin-2 areas where we do not observe any deaths due to small sample sizes, (iv) acknowledge differences in data sources by modeling potential bias arising from the various data sources. The methods are illustrated using household survey and census data from Kenya and Malawi, to produce mortality estimates from 1980 to the time of the most recent survey, and predictions to 2020.


Assuntos
Mortalidade da Criança , Países em Desenvolvimento , Criança , Humanos , Lactente , Mortalidade Infantil , Quênia , Malaui
7.
Molecules ; 26(24)2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34946501

RESUMO

Croton lechleri, commonly known as Dragon's blood, is a tree cultivated in the northwest Amazon rainforest of Ecuador and Peru. This tree produces a deep red latex which is composed of different natural products such as phenolic compounds, alkaloids, and others. The chemical structures of these natural products found in C. lechleri latex are promising corrosion inhibitors of admiralty brass (AB), due to the number of heteroatoms and π structures. In this work, three different extracts of C. lechleri latex were obtained, characterized phytochemically, and employed as novel green corrosion inhibitors of AB. The corrosion inhibition efficiency (IE%) was determined in an aqueous 0.5 M HCl solution by potentiodynamic polarization (Tafel plots) and electrochemical impedance spectroscopy, measuring current density and charge transfer resistance, respectively. In addition, surface characterization of AB was performed by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy techniques. Chloroform alkaloid-rich extracts resulted in IE% of 57% at 50 ppm, attributed to the formation of a layer of organic compounds on the AB surface that hindered the dezincification process. The formulation of corrosion inhibitors from C. lechleri latex allows for the valorization of non-edible natural sources and the diversification of the offer of green corrosion inhibitors for the chemical treatment of heat exchangers.


Assuntos
Cobre/química , Croton/química , Ácido Clorídrico/química , Extratos Vegetais/química , Zinco/química , Corrosão
8.
J Synchrotron Radiat ; 27(Pt 3): 653-663, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32381765

RESUMO

Synchrotron X-ray diffraction (XRD) measured on the XMaS beamline at the ESRF was used to characterize the alloy composition and crystalline surface corrosion of three copper alloy Tudor artefacts recovered from the undersea wreck of King Henry VIII's warship the Mary Rose. The XRD method adopted has a dynamic range ∼1:105 and allows reflections <0.002% of the height of major reflections in the pattern to be discerned above the background without smoothing. Laboratory XRD, scanning electron microscopy-energy dispersive spectroscopy, synchrotron X-ray fluorescence and X-ray excited optical luminescence-X-ray near-edge absorption structure were used as supporting techniques, and the combination revealed structural and compositional features of importance to both archaeology and conservation. The artefacts were brass links believed to be fragments of chainmail and were excavated from the seabed during 1981 and 1982. Their condition reflects very different treatment just after recovery, viz. complete cleaning and conservation, chemical corrosion inhibition and chloride removal only, and distilled water soaking only (to remove the chlorides). The brass composition has been determined for all three at least in the top 7 µm or so as Cu(73%)Zn(27%) from the lattice constant. Measurement of the peak widths showed significant differences in the crystallite size and microstrain between the three samples. All of the links are found to be almost chloride-free with the main corrosion products being spertiniite, sphalerite, zincite, covellite and chalcocite. The balance of corrosion products between the links reflects the conservation treatment applied to one and points to different corrosion environments for the other two.

9.
Anal Bioanal Chem ; 412(30): 8431-8442, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33135086

RESUMO

This work presents a corrosion study of 2-aminobenzimidazole (ABI) as a corrosion inhibitor for brass in chloride solution. Electrochemical, field emission scanning electron microscopy, atomic force microscopy, and contact angle measurements showed that ABI mitigates brass corrosion after short-, medium-, and long-term immersion periods. Next, a detailed surface analysis of the ABI adsorbed on the brass surface was performed using attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) techniques. XPS imaging was performed in association with principal component analysis to determine the different phases on the surface. In order to describe the in-depth composition of the ABI surface, an angle-resolved XPS analysis was performed. This analysis was further supported by gas cluster ion beam sputtering to gradually remove the ABI surface layer, and XPS analysis was performed after each sputtering cycle. Finally, TOF-SIMS analyses showed the formation of Cu/Cu2-ABI and Zn-ABI compounds, the 2D distribution of ABI-related compounds, and their thermal stability on the brass surface. Graphical abstract.

10.
Lett Appl Microbiol ; 71(5): 506-509, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32745274

RESUMO

There have been numerous reports in the literature describing the diversity of microbial flora isolated from woodwind and brass instruments, with potential infection risks for players, especially when such instruments are shared. Steam disinfection has become established as a trusted method of decontamination; however, there have been no reports on the employment of this technology to disinfect parts of musical instruments, hence it was the aim of this study to examine the fate of bacterial and yeast pathogens on artificially contaminated trumpet mouthpieces and to evaluate whether such disinfection is an effective method of disinfection for such instrument parts. Trumpet mouthpieces were artificially contaminated with 18 microbial strains (17 bacteria from four genera (Enterococcus, Escherichia, Staphylococcus and Streptococcus) and one yeast (Candida)), each at an inoculum density of approximately 1·5 × 107 colony forming units and subjected to a disinfection cycle. The experiment was repeated including 50% (v/v) sterile sputum as soil. No bacteria or yeast organisms were recovered post disinfection, including following recovery and with nonselective cultural enrichment techniques.


Assuntos
Bactérias/isolamento & purificação , Candida/isolamento & purificação , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Vapor , Enterococcus/isolamento & purificação , Equipamentos e Provisões/microbiologia , Escherichia/isolamento & purificação , Humanos , Música , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação
11.
J Appl Clin Med Phys ; 21(8): 216-223, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32592451

RESUMO

PURPOSE: This study was designed to evaluate skin dose in both VMAT and tangent treatment deliveries for the purpose of identifying suitable bolus use protocols that should produce similar superficial doses. METHODS: Phantom measurements were used to investigate skin dose in chest wall radiotherapy with and without bolus for 3D and rotational treatment techniques. Optically stimulated luminescence dosimeters (OSLDs) with and without housing and EBT3 film were used. Superflab (3, 5, and 10 mm) and brass mesh were considered. Measured doses were compared with predictions by the Eclipse treatment planning system. Patient measurements were also performed and the bolusing effect of hospital gowns and blankets were highlighted. The effect of flash for VMAT plans was considered experimentally by using 2 mm couch shifts. RESULTS: For tangents, average skin doses without bolus were 0.64 (EBT3), 0.62 (bare OSLD), 0.77 (jacketed OSLD), and 0.68 (Eclipse) as a fraction of prescription. For VMAT, doses without bolus were 0.53 (EBT3), 0.53 (bare OSLD), 0.64 (jacketed OSLD), and 0.60 (Eclipse). For tangents, the average doses with different boluses as measured by EBT3 were 0.99 (brass mesh), 1.02 (3 mm), 1.03 (5 mm), and 1.07 (10 mm). For VMAT with bolus, average doses as measured by EBT3 were 0.83 (brass), 0.96 (3 mm), 1.03 (5 mm), and 1.04 (10 mm). Eclipse doses agreed with measurements to within 5% of measurements for all Superflab thicknesses and within 15% of measurements for no bolus. The presence of a hospital gown and blanket had a bolusing effect that increased the surface dose by approximately 10%. CONCLUSIONS: Results of this work allow for consideration of different bolus thicknesses, materials, and usage schedules based on desired skin dose and choice of either tangents or an arc beam techniques.


Assuntos
Neoplasias da Mama , Radioterapia de Intensidade Modulada , Parede Torácica , Feminino , Humanos , Mastectomia , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador
12.
Nano Lett ; 19(3): 1832-1837, 2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30633522

RESUMO

It is imperative to explore practical methods and materials to drive the development of high energy density lithium metal batteries. The constuciton of nanostructure electrodes and surface engineering on the current collectors are the two most effective strategies to regulate the homogeneous Li plating/stripping to relieve the Li dendrites and infinite volume change problems. Based on the low stacking fault energy of the Cu-Zn alloy, we present a novel chemical energy release induced surface atom diffusion strategy, which is achieved by the negative Gibbs free energy from the surface oxidation reaction and subsequent replacement reaction under thermal treatment in air, to realize a uniform upper ZnO nanoparticles coating. Furthermore, we apply the modified brass mesh as a lithiophilic current collector to decrease the Li deposition nucleation overpotential and effectively restrain the Li dendrite growth. The modified brass current collector achieves a long-term cycling stability of 500 cycles at 2.0 mA cm-2. We have verified the effectiveness of our chemical energy release modification strategy on a 1 m2 brass mesh and other Cu alloy (Tin bronze mesh), which demonstrates its great opportunities for scalable and safe lithium metal batteries.

13.
J Gen Intern Med ; 33(7): 1084-1091, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29663280

RESUMO

BACKGROUND: Discharge planning is an important component of hospital care. The Blaylock Risk Assessment Screening Score (BRASS) index is an instrument used to identify patients requiring complex discharge planning. OBJECTIVES: (1) Evaluate the ability of the original BRASS index to predict the risk of complex discharge and hospital mortality. (2) Develop and validate a simplified BRASS index by eliminating redundant variables and re-estimating the predictor weights. DESIGN: Prospective cohort study. PARTICIPANTS: Patients admitted at the general internal medicine wards of tertiary referral hospital in Turin, Italy, and screened within 48 h using the BRASS index. METHODS: The first phase of the study assessed the performance of the original BRASS index in predicting the risk of complex discharge and hospital mortality, then a simplified score was developed. In the second phase, temporal validation of the simplified BRASS index was performed. The probability of each discharge modality (discharged at home without complications, complex discharge, and dead in hospital) was modeled using polytomous logistic regression. The AUC was used to compare the performance of the different models. KEY RESULTS: Among 6044 patients in the first phase of the study, 63% were discharged at home without complications, 31% had complex discharge, and 6% died during the hospital stay. The AUC of the simplified BRASS index, compared with the original index were 0.71 vs. 0.70 for complex discharge and 0.83 vs. 0.80 for hospital mortality. In the validation set (3325 patients), the simplified BRASS index discriminates the outcome categories with an AUC of 0.69 and 0.81 for complex discharge and hospital mortality, respectively. CONCLUSION: The new, simplified BRASS index showed a slightly better performance in predicting the risk of complex discharge and hospital mortality than the original tool and takes less time to be applied. These results were also confirmed in the validation set.


Assuntos
Medicina Interna/normas , Programas de Rastreamento/normas , Alta do Paciente/normas , Medicina de Precisão/normas , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Medicina Interna/métodos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Medicina de Precisão/métodos , Estudos Prospectivos , Medição de Risco/métodos , Medição de Risco/normas
14.
Popul Health Metr ; 16(1): 7, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29650013

RESUMO

BACKGROUND: Life expectancy considerably increased in most developed countries during the twentieth century. However, the increase in longevity is neither uniform nor random across individuals belonging to various socioeconomic groups. From an economic policy perspective, the difference in mortality by socioeconomic conditions challenges the fairness of the social security systems. We focus on the case of Italy and aim at measuring differences in longevity at older ages by individuals belonging to different socioeconomic groups, also in order to assess the effective fairness of the Italian public pension system, which is based on a notional defined contribution (NDC) benefit computation formula, whose rules do not take into account individual heterogeneity in expected longevity. METHODS: We use a longitudinal dataset that matches survey data on individual features recorded in the Italian module of the EU-SILC, with information on the whole working life and until death collected in the administrative archives managed by the Italian National Social Security Institute. In more detail, we follow until 2009 a sample of 11,281 individuals aged at least 60 in 2005. We use survival analysis and measure the influence of a number of events experienced in the labor market and individual characteristics on mortality. Furthermore, through Kaplan-Meier simulations of hypothetical social groups, adjusted by a Brass relational model, we estimate and compare differences in life expectancy of individuals belonging to different socioeconomic groups. RESULTS: Our findings confirm that socioeconomic status strongly predicts life expectancy even in old age. All estimated models show that the prevalent type of working activity before retirement is significantly associated with the risk of death, even when controlling for dozens of variables as proxies of individual demographic and socioeconomic characteristics. The risk of death for self-employed individuals is 26% lower than that of employees, and life expectancy at 60 differs by five years between individuals with opposite socioeconomic statuses. CONCLUSIONS: Our study is the first that links results based on a micro survival analysis on subgroups of the elderly population with results related to the entire Italian population. The extreme differences in mortality risks by socioeconomic status found in our study confirm the existence of large health inequalities and strongly question the fairness of the Italian public pension system.


Assuntos
Emprego , Disparidades nos Níveis de Saúde , Expectativa de Vida , Longevidade , Ocupações , Classe Social , Previdência Social , Idoso , Demografia , Países Desenvolvidos , Feminino , Humanos , Renda , Itália , Masculino , Pessoa de Meia-Idade , Pensões , Aposentadoria , Fatores Socioeconômicos , Trabalho
15.
Angew Chem Int Ed Engl ; 56(52): 16579-16582, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29193586

RESUMO

Electrochemically reducing CO2 into fuels using renewable electricity is a contemporary global challenge that requires significant advances in catalyst design. Photodeposition techniques were used to screen ternary alloys of Cu-Zn-Sn, which includes brass and bronze, for the electrocatalytic reduction of CO2 to CO and formate. This analysis identified Cu0.2 Zn0.4 Sn0.4 and Cu0.2 Sn0.8 to be capable of reaching Faradaic efficiencies of >80 % for CO and formate formation, respectively, and capable of achieving partial current densities of 3 mA cm-2 at an overpotential of merely 200 mV.

16.
Eur J Nucl Med Mol Imaging ; 43(7): 1315-22, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26780619

RESUMO

PURPOSE: Even though [(123)I]FP-CIT SPECT provides high accuracy in detecting nigrostriatal cell loss in neurodegenerative parkinsonian syndromes (PS), some patients with an inconclusive diagnosis remain. We investigated whether the diagnostic accuracy in patients with clinically uncertain PS with previously inconclusive findings can be improved by the use of iterative reconstruction algorithms and an improved semiquantitative evaluation which additionally implemented a correction algorithm for patient age and gamma camera dependency (EARL-BRASS; Hermes Medical Solutions, Sweden). METHODS: We identified 101 patients with inconclusive findings who underwent an [(123)I]FP-CIT SPECT between 2003 and 2010 as part of the diagnostic process of suspected PS at the University of Munich, and re-evaluated these scans using iterative reconstruction algorithms and the new corrected EARL-BRASS. Clinical follow-up was obtained in 62 out of the 101 patients and constituted the gold standard for the re-evaluation to assess the possible improvement in diagnostic accuracy. RESULTS: Clinical follow-up confirmed the diagnosis of PS in 11 of the 62 patients. In patients in whom both visual and semiquantitative analysis showed concordant findings (48 patients), a high negative predictive value (93 %), positive predictive value (100 %) and accuracy (94 %) were found, and thus a correct diagnosis was obtained in 45 of the 48 patients. Among the 14 patients with discordant findings, the additional semiquantitative analysis correctly identified all five of nine patients patients without PS by nonpathological semiquantitative findings in visually pathological or inconclusive scans. In contrast, four of the remaining five patients with decreased semiquantitative values but visually normal scans did not show a PS during follow-up. CONCLUSION: The age-corrected and camera-corrected mode of evaluation using EARL-BRASS provided a notable improvement in the diagnostic accuracy of [(123)I]FP-CIT SPECT in PS patients with previously inconclusive findings. The gain in accuracy might be achieved by better discrimination between physiological low striatal [(123)I]FP-CIT binding due to age-related loss of the dopamine transporter or pathological loss of binding.


Assuntos
Bases de Dados Factuais , Transtornos Parkinsonianos/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Tropanos , Incerteza , Estudos de Casos e Controles , Europa (Continente) , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
17.
Environ Res ; 151: 275-285, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27512893

RESUMO

This study examines arsenic, copper, lead and manganese drinking water contamination at the domestic consumer's kitchen tap in homes of New South Wales, Australia. Analysis of 212 first draw drinking water samples shows that almost 100% and 56% of samples contain detectable concentrations of copper and lead, respectively. Of these detectable concentrations, copper exceeds Australian Drinking Water Guidelines (ADWG) in 5% of samples and lead in 8%. By contrast, no samples contained arsenic and manganese water concentrations in excess of the ADWG. Analysis of household plumbing fittings (taps and connecting pipework) show that these are a significant source of drinking water lead contamination. Water lead concentrations derived for plumbing components range from 108µg/L to 1440µg/L (n=28, mean - 328µg/L, median - 225µg/L). Analysis of kitchen tap fittings demonstrates these are a primary source of drinking water lead contamination (n=9, mean - 63.4µg/L, median - 59.0µg/L). The results of this study demonstrate that along with other potential sources of contamination in households, plumbing products that contain detectable lead up to 2.84% are contributing to contamination of household drinking water. Given that both copper and lead are known to cause significant health detriments, products for use in contact with drinking water should be manufactured free from copper and lead.


Assuntos
Arsênio/análise , Cobre/análise , Água Potável/análise , Chumbo/análise , Manganês/análise , Humanos , New South Wales
18.
Aging Clin Exp Res ; 27(6): 849-56, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25911607

RESUMO

BACKGROUND: Discharge planning is a critical feature of hospital's care in geriatric rehabilitation centers. The aim of this study was to evaluate the effects of comorbidity and functionality in identifying patients who are at risk of discharge problems. We also evaluate the association between Blaylock Risk Assessment Screening Score, BRASS index (BI), and post-hospitalization outcome (PHO). METHODS: Eighty patients (58 women and 22 men, with mean age equal to 83.28 ± 6.77 years) at geriatric rehabilitation division admission were screened with Geriatric Multidimensional Assessment (GMA). Then, BI and PHO were evaluated (mean follow-up time was 205.1 ± 95.8 days). By Structural Equation Model, we evaluated the existing causal relationships between comorbidity, functionality and PHO, elements of GMA, and the association between PHO and BI. RESULTS: Comorbidity acted on PHO through functionality with indirect effect only (+0.703, P = 0.019). So, the functionality assumes a pivotal role of the causal relationship comorbidity to PHO. BI is positively associated with PHO: correlation returned was equal to +0.313 (P = 0.019). CONCLUSIONS: The comorbidity has a role in getting worse PHO, but its effect is possible only through the mediation of functional status. The study also demonstrated the positive association between BI and PHO.


Assuntos
Comorbidade , Doenças do Sistema Nervoso/reabilitação , Alta do Paciente , Ferimentos e Lesões/reabilitação , Atividades Cotidianas , Assistência ao Convalescente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Idoso Fragilizado/estatística & dados numéricos , Avaliação Geriátrica/métodos , Humanos , Masculino , Modelos Estatísticos , Prognóstico , Medição de Risco/métodos , Resultado do Tratamento
19.
Environ Pollut ; 352: 124154, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38750810

RESUMO

Corrosion of brass plumbing materials may lead to metal release and deteriorate the drinking water quality. In this study, the initial corrosion of brass coupon cut from commercially available water meter was investigated. High rates of Pb, Cu and Zn release from the brass coupon were found during the early stage of corrosion (0-5 d) due to general corrosion and galvanic corrosion. The corrosion current density (Icorr) increased and resistance (RF) decreased during this period indicating that severe corrosion had occurred. In a later stage (5-30 d), a decreased Icorr and an increased RF were observed due to the development of a denser layer of Pb and Cu corrosion products which regulated the release of soluble Pb and Cu. The release of Zn continued and no significant Zn precipitation was found. Overall, particulate Pb, particulate Cu and soluble Zn dominated in the metal release during the initial corrosion of brass. The release of Pb, Cu and Zn was enhanced by a lower pH. Free chlorine was found to slightly reduce the release of Pb but promote the release of Cu and Zn. The presence of Pb on the brass surfaces was found to alleviate the dezincification process. A conceptual model based on metal release profile and electrochemical characterization was proposed to describe the initial corrosion of brass in typical drinking water.


Assuntos
Cobre , Água Potável , Chumbo , Poluentes Químicos da Água , Zinco , Corrosão , Cobre/química , Cobre/análise , Zinco/química , Zinco/análise , Chumbo/química , Chumbo/análise , Água Potável/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise
20.
Chemosphere ; 355: 141835, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552799

RESUMO

This study provides insights regarding the selective metal leaching of brass in various tap water conditions, which benefits water utilities to predict the potential of metal released from brass water meters. The long-term time-dependent selective metal dissolution of brass with various ß phase fractions have not previously been investigated. In this study, a 201-d immersion experiment was carried out in low and high conductivity tap water (LCTW and HCTW, respectively). Three commercialized brass samples in different ß phase fractions (ß = 51%, ß = 43%, ß = 39%), named brass 51, brass 43, and brass 39, respectively, were used. The results showed that brass 51 had the most negative corrosion potential (-0.17 V) and the lowest polarization resistance (8.5 kΩ) compared to brass 43 and brass 39 (-0.04 V and 10.1-14.7 kΩ, respectively) in LCTW. This trend was verified by the 201-d immersion experiment in which brass 51 exhibited the highest zinc leaching rate (21-30 µg L-1 cm-2 d-1), followed by brass 43 and brass 39 (16-23 µg L-1 cm-2 d-1) in both waters. The leaching amounts of lead and copper were extremely low compared to zinc. In LCTW, the uniform corrosion (UC) mechanism dominated from day 1 to day 120. Afterwards, UC was replaced by the galvanic corrosion (GC) mechanism, with the selective leaching coefficient of Zn over Cu (SZn/Cu) increasing from 10 to 25 to 40-80. In HCTW, however, the SZn/Cu reached 300-1000, and the transition of UC to GC occurred earlier on day 30 due to the rapid formation of the ZnO layer on the brass surface that hindered the ion attack.


Assuntos
Cobre , Água , Chumbo , Zinco
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