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1.
Anal Methods ; 16(14): 2009-2018, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38517487

RESUMO

Surfactants from detergents, when inadequately treated in sewage treatment plants, are carried away into estuaries, resulting in the contamination of aquatic environments. It is thus necessary to develop rapid and efficient techniques that are capable of effectively monitoring these pollutants. In this context, for the first time in the literature, this study reports the development and application of a digital image-based (DIB) method for the in situ quantification of the anionic surfactant linear alkylbenzene sulfonate (LAS) in water bodies using a smartphone. The DIB method is a highly effective modern detection method based on methylene blue, which is employed as a modified alternative technique to the spectrophotometric method and commonly used in environmental studies; in the DIB method, the images of interest are obtained using a smartphone and the analyses are carried out using free software Color grab. The results obtained from the application of the DIB method showed that the method possesses high precision and accuracy, with a linear calibration curve in the range of 0.15 to 4.5 mg L-1, R2 = 0.993, a limit of detection of 6.0 µg L-1, and recovery rates ranging from 82.7% to 114%. The efficacy of the proposed method was evaluated by comparing its results with those of spectrophotometry (used as a reference method) through the analysis of environmental samples obtained from the Capibaribe River Estuary using methylene blue. No statistically significant differences were observed between the results obtained from the DIB and the spectrophotometric method. The innovative method proposed in this study is fast, economical and environmentally friendly; the technique involves the use of only a few microliters of samples and generates little waste compared to spectrophotometry. In addition, the proposed method is applicable for in situ analyses, allowing real-time monitoring of LAS in different types of aquatic environments.

2.
BMJ Open ; 14(2): e075886, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38423767

RESUMO

INTRODUCTION: Despite greater needs in rural areas, occupational therapists are maldistributed to urban spaces which limits service access and health outcomes for rural people and communities. Preparation of students for rural practice may improve rural workforce recruitment and retention; however, the range and scope of preparation strategies employed by education providers are unclear. This scoping review aims to understand and describe the range of strategies education services use to prepare occupational therapy students for rural practice across the globe. METHODS AND ANALYSIS: The study will include all publications about strategies used to prepare occupational therapy students for future rural practice, prior to enrolment, during the programme or on graduation. MEDLINE (Ovid), Emcare (Ovid), APA PsychInfo (Ovid), CINAHL (EBSCOhost), Health Source: Nursing/Academic (EBSCOHost), Educational Resources Information Centre (ERIC), Open Access Theses and Dissertations (OATD), and Scientific Electronic Library Online (SciELO) databases will be systematically searched in English, Spanish, French and Portuguese languages. Citations will be screened by two or more independent researchers against inclusion criteria and data extracted from included publications using a customised extraction tool. Frequency counts will be provided for study type, student location and sociodemographics, and the timing/educational strategy. The extracted data will be analysed using a matrix framework and presented in diagrammatic/tabular form and accompanied by a narrative summary which will describe how the results relate to the reviews' questions. ETHICS AND DISSEMINATION: This study will not involve human/animal subjects and does not require ethics approval. Results will be disseminated to relevant groups in peer-reviewed journal(s) and at relevant occupational therapy, higher education and/or rural health conferences. Results will also be translated and shared in blogs/social media to support access for non-research audiences and shared with other regional universities to influence curriculum design.


Assuntos
Terapia Ocupacional , Humanos , Terapeutas Ocupacionais , Estudantes , Projetos de Pesquisa , Revisões Sistemáticas como Assunto
3.
Anal Methods ; 15(42): 5683-5691, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37861715

RESUMO

In the present work, we report the development of a novel cotton thread-based colorimetric sensor modified by carboxymethylcellulose (CMC) and cuprizone (CPZ) with smartphone detection and its application for the quantitative determination of cupric ions in water and cachaça. The cotton thread/smartphone detection-based colorimetric method is an easily affordable, low-cost technique which allows one to perform real-time and on-field determination analyses, especially with limited financial resources. The method involves the complexation of Cu(II) with CPZ, which causes a change in the coloration of the cotton thread from a shade of white to blue in the detection zone of the colorimetric sensor. The immobilization of CPZ on CMC in the cotton thread leads to the pre-concentration of Cu(II) via a complexation mechanism with colorimetric reaction. The application of the colorimetric sensor allows the quantification of copper in the range from 1 to 12 mg L-1, with a low limit of detection of 0.21 mg L-1. In addition, the recovery assays conducted in samples of water and cachaça resulted in recovery percentages ranging from 84.9% to 107%, which is indicative of a precise method. To validate the precision of the proposed colorimetric method, the values obtained from the quantification analysis were compared with those of the flame atomic absorption spectrometry and a good agreement at the 95% confidence level was obtained.

4.
Anal Methods ; 15(37): 4827-4833, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37587794

RESUMO

The present work describes a laboratory-on-a-drone (Lab-on-a-Drone) developed to perform in situ detection of contaminants in environmental water samples. Toward this goal, the system was mounted on an unmanned aerial vehicle (UAV) (drone) and remotely controlled via Wi-Fi to acquire a water sample, perform the electrochemical detection step, and then send the voltammetry data to a smartphone. This Lab-on-a-Drone system was also able to recharge its battery using a solar cell, greatly increasing the autonomy of the system, even in the absence of a power line. As a proof of concept, the Lab-on-a-Drone was employed for the detection of Pb2+ in environmental waters, using a simple electrochemical cell containing a miniaturized screen-printed boron-doped diamond electrode (SP-BDDE) as a working electrode, an Ag/AgCl as a reference electrode, and a graphite ink as a counter electrode. For quantification purposes, analytical curves were constructed covering a concentration range from 1.0 µg L-1 (4.83 nmol L-1) to 80.0 µg L-1 (386.10 nmol L-1), featuring a detection limit of 0.062 µg L-1 (0.30 nmol L-1). The Lab-on-a-Drone was applied to monitor a water reservoir in the Metropolitan Region of Recife, Brazil. To evaluate its performance regarding accuracy and precision, a reference method based on inductively coupled plasma optical emission spectrometry (ICP-OES) was applied, and the results obtained by both methods showed no statistical differences (t-test at 95% confidence level, n = 3). These results represent the first demonstration of the capabilities of an adapted UAV for the quantification of electroactive environmental contaminant using voltammetry, with real-time data transmission. Thus, the Lab-on-a-Drone makes it possible to reach difficult-to-access environmental reserves and to monitor potentially polluting activity in distant water bodies. Thus, this tool can be used by governments and non-profit organizations to monitor environmental waters using fast, low-cost, process autonomy with accurate and precise data useful to decision making.

5.
Anal Biochem ; 671: 115135, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37019253

RESUMO

Given the importance of identifying the presence of biomarkers of human diseases in DNA samples, the main objective of this work was to investigate, for the first time, the electro-catalytic oxidation of 7-methyl-guanine (7-mGua) and 5-methyl-cytosine (5-mCyt) on a boron doped diamond electrode pre-treated cathodically (red-BDDE), using differential pulse voltammetry (DPV) and cyclic voltammetry (CV). The anodic peak potentials of 7-mGua and 5-mCyt by DPV were at E = 1.04 V and E = 1.37 V at pH = 4.5, indicating excellent peak separation of approximately 330 mV between species. Using DPV, experimental conditions such as supporting electrolyte, pH and influence of interferents were also investigated to develop a sensitive and selective method for individual and simultaneous quantification of these biomarkers. The analytical curves for the simultaneous quantification of 7-mGua and 5-mCyt in the acid medium (pH = 4.5) were: concentration range of 0.50-5.00 µmol L-1 (r = 0.999), detection limit of 0.27 µmol L-1 for 7-mGua; from 3.00 to 25.00 µmol L-1 (r = 0.998), with a detection limit of 1.69 µmol L-1 for 5-mCyt. A new DP voltammetric method for the simultaneous detection and quantification of biomarkers 7-mGua and 5-mCyt using a red-BDDE is proposed.


Assuntos
5-Metilcitosina , Boro , Humanos , Oxirredução , Eletrodos , Guanina
6.
Anal Methods ; 15(19): 2300-2308, 2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37089039

RESUMO

The present study reports, for the first time, the development and application of a highly efficient method based on digital imaging analysis for the simultaneous determination of Cu2+ and furfural in cachaça samples using a two-phase system and chemometrics tools. Furfural reacts with aniline in an acidic medium to form a Schiff base, which exhibits a pink color. On the other hand, Cu2+ reacts with cuprizone in a basic medium to form a blue complex. The two reactions were performed on a porcelain plate, and a smartphone was used to capture the colorimetric images. Partial least squares (PLS) regression was used to construct the prediction models for Cu2+ and furfural contents in cachaça samples. After finding the best PLS models, the ordered predictor selection (OPS) analysis was performed in order to select the most predictive variables. The method developed was found to be effective in estimating the amounts of Cu2+ and furfural in cachaça samples, with a mean absolute error of 0.2 mg L-1 for the Cu2+ model, and 0.3 mg per 100 mL of anhydrous alcohol for the furfural model. The method proposed in this study is simple and straightforward; it does not require complex technical knowledge and can be used by the producers themselves in the cachaça manufacturing process.

7.
Aust Occup Ther J ; 70(1): 119-141, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35949174

RESUMO

INTRODUCTION: Regional, rural, and remote people represent nearly half the world's population yet experience disproportionally higher disease, mortality, and disability rates, coupled with limited healthcare access. Occupational therapy has committed to occupational justice, yet no descriptive framework of services provided by occupational therapists in non-urban locations exists. Understanding current non-urban service practices will provide a basis for non-urban service development and research to reduce this inequity. METHODS: Four databases were systematically searched for publications describing non-urban occupational therapy services, from any country, written in English, French, Portuguese, or Spanish, from 2010 to 2020. Publications were screened against criteria for inclusion, and data were identified using an extraction tool and presented in a frequency table, on a map, and in a searchable supporting information Table S1. RESULTS: Only 117 publications were included discussing services provided to populations across 19 countries. They were mostly published in English (98%) and about populations from English-speaking countries (70%). Included publications discussed individualist services (65%), for defined age groups (74%), and for people with specific medical diagnoses (58%). Services were commonly provided in the client's community (56%), originating from urban locations (45%) where the provider travelled (26%) or contacted clients using telehealth (19%). Individual 1:1 enabling strategies were most described (59%), including remediation (34%), compensation (9%), or education (7%). Community enablement strategies were infrequently described (14%), focused primarily on transformation to improve existing service delivery (9%), with some redistributive justice (3%), and one community development strategy (1%). Exploratory research services accounted for the remaining studies (27%). Differences were noted between Global North and South approaches. CONCLUSION: Globally, occupational therapy has limited focus on non-urban services and favours individualist rehabilitative strategies provided by therapists remote from the client's context. Further research is required on the effectiveness and appropriateness of occupational therapy strategies to improve rural/urban inequity and health outcomes.


Assuntos
Terapia Ocupacional , Serviços de Saúde Rural , Telemedicina , Humanos , Acessibilidade aos Serviços de Saúde , Pessoal Técnico de Saúde , Terapeutas Ocupacionais
8.
Aust Occup Ther J ; 70(1): 142-156, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36193547

RESUMO

INTRODUCTION: Rural communities contribute to national wellbeing, identities, economies, and social fabrics yet experience increased risk of mortality, morbidity, and disability, coupled with lower levels of income, formal education, and employment than urban citizens. Despite higher need, occupational therapy services are maldistributed to urban locations. Publications about non-urban services discuss predominantly outreach-based, individualist, rehabilitation for specified diagnoses/age groups. However, given this population level inequity, it is unclear why individualist focussed services are more commonly discussed. Understanding intentions expressed in publications about non-urban service design may identify assumptions/limitations to current approaches and contribute to improved future services. METHODS: Each of 117 publications identified in a scoping review was read by two reviewers to independently identify themes. Provisional themes were discussed and modified in an iterative process to develop final themes/subthemes. The first author reinterrogated the publications and coded data to identify relevant examples to support the identified themes. RESULTS: Three key themes and nine subthemes were identified. Hegemonic perspectives were found in the themes (i) Extension of urban practice and (ii) Austerity, particularly in the Global North. Non-urban services were typically extended to non-urban contexts underpinned by austerity and neoliberal values such that non-urban persons and their context were problematised rather than service or funding design. A counter-hegemonic perspective was found in the theme (iii) Responses to situational realities more commonly in Global South publications, which valued non-urban contexts, and focussed on developing non-urban communities and promoting justice. CONCLUSION: The hegemonic paradigm links occupational therapy services with neoliberal notions of individualism, private provision of care, and efficiency/market value, rather than the occupational therapy values for justice. The profession must consider our role in perpetuating injustice for non-urban people and consider if and how more contextually tailored counter hegemonic place-based paradigms can be developed from and with regional, rural, and remote practice.


Assuntos
Pessoas com Deficiência , Terapia Ocupacional , Humanos , Emprego
9.
Anal Methods ; 14(26): 2631-2641, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35736378

RESUMO

In this work, a simple, low-cost and easy-to-handle analytical procedure based on carbon quantum dots (CQDs) is proposed to check commercially available formulated microbicides that are used to mitigate the transmission of viruses, such as SARS-COV-2, or bacterial diseases. For this purpose, CQDs were synthesized via pyrolysis using citric acid and ethylenediamine as precursors to produce an intense fluorescence that is used to measure the concentration of hypochlorite, an important biocidal agent present in sanitizing mats, by quenching mechanisms. The characterization of the CQDs was performed using IR spectrophotometry, UV-Vis spectrophotometry, spectrofluorometry, thermogravimetric analysis, scanning electron microscopy, dynamic light scattering, X-ray diffraction, energy-dispersive spectroscopy, and zeta potential measurements. For analytical purposes, fluorescence was measured in a UV chamber irradiated using an LED with the maximum emission at 350 nm. A smartphone was coupled to the UV chamber to measure the fluorescence quenching due to the presence of hypochlorite, and further the digital images were decomposed by RGB data using free software. Tests of pH, CQD concentration and stability of the fluorescence emitted were performed. The stability study of the fluorescence emitted by the CQD solution showed a relative standard deviation lower than 5.0%. The fluorescence digital image-based (FDIB) method resulted in a linear range from 17.44 µmol L-1 to 90.0 µmol L-1 with an LOD of 3.30 µmol L-1 for the determination of hypochlorite using a microplate made of PLA (polylactic acid) customized using a 3D printer. Furthermore, the hypochlorite concentration was tested in situ for its compliance in a sanitizing mat, in a real use situation (daily, a group of four people, each one kept their feet on the mat for 30 s). After 2.5 h, the monitored concentration of hypochlorite was 0.04953% (w/v) or 7.63 mmol L-1, and therefore, it was inefficient to act as a sanitizing agent. Thus, for the first time in the literature, an FDIB method with CQDs is used to verify in situ microbicide practices with a fast and low-cost analytical procedure.


Assuntos
COVID-19 , Pontos Quânticos , Carbono/química , Carbono/farmacologia , Humanos , Ácido Hipocloroso , Pontos Quânticos/química , SARS-CoV-2
10.
Anal Methods ; 14(13): 1311-1319, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35275146

RESUMO

In the present work a voltammetric method was developed for in situ detection of 2,4-dichlorophenoxyacetic acid (2,4-D) in environmental water samples, using a compact and lightweight electrochemical cell using a fused deposition modeling (FDM) 3D printer with biodegradable polylactic acid filament, and a boron-doped diamond electrode (BDDE). The samples were collected by an adapted unmanned aerial vehicle (UAV) with a micropump and a miniature solenoid valve powered by an open source microcontroller. After optimizing the supporting electrolyte, pH and parameters of the square wave voltammetry (SWV) a linear analytical curve for 2,4-D in 0.5 mol L-1 Na2SO4 (pH = 2.0 regulated using 0.5 mol L-1 H2SO4 solution) in a concentration range from 100 nmol L-1 to 911 nmol L-1 with 34 nmol L-1 as the limit of detection was obtained. The same samples in situ analyzed by SWV were sent to the laboratory for gas chromatography-mass spectrometry (GC-MS) analysis; and there was no statistical difference from the concentration of 2,4-D in any of the samples at a 95% confidence level. Therefore, the method developed for quantification of 2,4-D in water provides an important environmental monitoring tool since it enables access to difficult areas in a fast, practical and safe way. This is the first time that an adapted UAV with these features has been used to collect environmental water for in situ electrochemical analysis as a screening tool to alert the presence of environmental hazard compounds, such as 2,4-D. Thus, this method can be used by environmental and sanitary control agencies to monitor or to supervise environmental water quality with response in real time.


Assuntos
Boro , Fenoxiacetatos , Ácido 2,4-Diclorofenoxiacético , Boro/química , Eletrodos
11.
Int J Occup Saf Ergon ; 28(3): 1699-1704, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34006199

RESUMO

Objectives. Lower back pain (LBP) is a common health problem worldwide, affecting an increasing number of individuals. Military firefighters (MFFs) face high levels of physical and psychological demands and are commonly exposed to different occupational risk factors. This study aimed to estimate the prevalence of chronic lower back pain (CLBP) in Brazilian enlisted MFFs. Methods. This cross-sectional study was carried out at the Military Firefighters Department of the Brazilian Federal District (Corpo de Bombeiros Militar do Distrito Federal [CBMDF]). The estimated sample size was 608 MFFs. Results. Of the 623 participants, 575 valid and complete questionnaires were analyzed. A total of 183 participants reported CLBP, indicating a point prevalence of 31.8% (95% confidence interval [CI] [28.2, 35.4]). The prevalence of acute and subacute LBP was 9.2% (95% CI [7.1, 11.9]), and 59% (95% CI [54.9, 62.9]) reported no back pain. CLBP was more common among men aged 40-49 years, who were insufficiently active and overweight. Conclusion. Around one-third of the study population reported CLPB. Prevalence estimates of CLPB were greater among men and those between 40 and 49 years old. Our data support the need for programs to prevent and treat CLBP among firefighters.


Assuntos
Dor Crônica , Bombeiros , Dor Lombar , Militares , Adulto , Brasil/epidemiologia , Dor Crônica/complicações , Dor Crônica/epidemiologia , Estudos Transversais , Humanos , Dor Lombar/psicologia , Masculino , Pessoa de Meia-Idade , Prevalência
12.
Environ Manage ; 68(4): 445-452, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34341867

RESUMO

The Tocantins-Araguaia Basin is one of the largest river systems in South America, located entirely within Brazilian territory. In the last decades, capital-concentrating activities such as agribusiness, mining, and hydropower promoted extensive changes in land cover, hydrology, and environmental conditions. These changes are jeopardizing the basin's biodiversity and ecosystem services. Threats are escalating as poor environmental policies continue to be formulated, such as environmentally unsustainable hydropower plants, large-scale agriculture for commodity production, and aquaculture with non-native fish. If the current model persists, it will deepen the environmental crisis in the basin, compromising broad conservation goals and social development in the long term. Better policies will require thought and planning to minimize growing threats and ensure the basin's sustainability for future generations.


Assuntos
Ecossistema , Rios , Animais , Biodiversidade , Conservação dos Recursos Naturais , Política Ambiental
13.
JBI Evid Synth ; 19(8): 1964-1970, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34400597

RESUMO

OBJECTIVE: The objective of this review is to complete a global synthesis of the evidence on occupational therapy services provided in non-urban areas. INTRODUCTION: Worldwide, non-urban populations experience higher levels of disease, mortality, and disease risk factors, yet most health services, including occupational therapy, are disproportionately located in urban areas. Research has predominantly focused on attracting therapists to non-urban practice by exploring generalized expressed needs from existing non-urban therapists, such as access to professional development, backfilling of jobs, peer and other practice supports, or enticing occupational therapy students through placement experiences. However, the types of service that non-urban occupational therapists routinely provide remains unclear. Clarifying the scope of occupational therapy services in non-urban areas will support educators and policy makers to plan curricula and services to support non-urban clinicians and communities. INCLUSION CRITERIA: This scoping review will consider qualitative and quantitative research studies and opinion pieces about occupational therapy services provided to any individuals or groups living in rural (non-urban) areas across the world. METHODS: The search will be conducted in MEDLINE (Ovid), CINAHL (EBSCOhost), Emcare, and ProQuest Nursing and Allied Health, and limited to studies published from 2010 in English, French, Portuguese, or Spanish. Titles and abstracts will be screened by two independent reviewers against predefined inclusion criteria, followed by detailed assessment and appraisal by two independent reviewers. Reasons for including or excluding studies will be recorded. Data will be extracted using a charting table and presented in tabular form with a narrative summary describing how the results relate to the review question.


Assuntos
Terapia Ocupacional , Atenção à Saúde , Serviços de Saúde , Humanos , Terapeutas Ocupacionais , Literatura de Revisão como Assunto , População Rural
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 253: 119580, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33618261

RESUMO

In this work we propose for the first time, a paper-based test strip to analyse Cu2+ content in sugar cane spirits, which, due to its simplicity, high portability and fast analytical response (3 min), can be easily applied to in situ analyses by producers. The test strip was developed aiming: i) identify qualitatively the Cu2+ content in sugar cane spirits, and, ii) determine quantitatively the Cu2+ content using a digital image method employing a smartphone. The paper-based test strip was functionalized with cuprizone and optimized through a Box-Behnken, an experimental design for obtaining the best reaction conditions. Based on qualitative method with naked eyes approach performed by six volunteers analyst untrained, the method present a percentage of accuracy of 93%. For the quantitative analysis, it was determined the metal content at a level of statistical agreement with the reference method, as well as it was obtained the dynamic linear range from 2 to 13 mg L-1 with limits of detection and quantification of 0.034 and 0.103 mg L-1, respectively. Furthermore, the quantitative method showed a reliable precision with an RSD of 4.3% (n = 10) and the recovery of Cu2+ ranged from 80 to 103.8%.


Assuntos
Saccharum , Bebidas Alcoólicas/análise , Cuprizona , Grão Comestível , Humanos , Smartphone
16.
Food Chem ; 338: 127800, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798815

RESUMO

For the first time, a method is proposed for colorimetric determination of reducing sugars in cachaça employing digital image and a smartphone as detector. The method was based on the reduction of Cu(II) to Cu(I) by sugars and followed by the formation of a colored Cu(I)-Neocuproine complex. A calibration curve was linear from 0.1 to 15 g L-1 for glucose and fructose with limits of detection of 0.012 g L-1 and 0.010 g L-1, respectively. It was observed that the non-aged cachaças, known for having inferior flavors and aromas, had a reducing sugar content three times higher than the aged cachaças, once a common practice among producers is to add sugar to adjust sensory deficits in the final product. Furthermore, the method is simple, does not require complex technical knowledge and it could be used as a tool to check possible fraud, adulteration or non-compliance to the law.


Assuntos
Bebidas Alcoólicas/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Smartphone , Açúcares/análise , Colorimetria/instrumentação , Colorimetria/métodos , Cobre/química , Desenho de Equipamento , Contaminação de Alimentos/análise , Frutose/análise , Glucose/análise , Fenantrolinas/química , Saccharum
17.
Chaos ; 30(8): 083115, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32872816

RESUMO

Chimera states are spatiotemporal patterns in which coherent and incoherent dynamics coexist simultaneously. These patterns were observed in both locally and nonlocally coupled oscillators. We study the existence of chimera states in networks of coupled Rössler oscillators. The Rössler oscillator can exhibit periodic or chaotic behavior depending on the control parameters. In this work, we show that the existence of coherent, incoherent, and chimera states depends not only on the coupling strength, but also on the initial state of the network. The initial states can belong to complex basins of attraction that are not homogeneously distributed. Due to this fact, we characterize the basins by means of the uncertainty exponent and basin stability. In our simulations, we find basin boundaries with smooth, fractal, and riddled structures.

18.
Transl Vis Sci Technol ; 9(7): 7, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32832214

RESUMO

Purpose: To evaluate the impact of instillation angle and nozzle tip geometry on cross-contamination risk of multidose ocular solution bottles. Methods: Pseudomonas aeruginosa solution was passed exclusively on the outside of the nozzle to simulate contamination on the exterior of topical agents. Three drops were administered from angles of 90° and 45° from bottles with either a round or sharp tip geometry, and the cultures were examined for growth. Two-hundred sixteen cultures from nine lubricant eyedrop brands currently existing in the Brazilian market were assessed for bacterial growth. Results: After seven days, bacterial contamination was detected in 53.7% of cultures when drops were administered at 90° and in 70.4% of cultures at 45°. Eyedrops collected from a rounded nozzle tip and an instillation angle of 90° transmitted bacteria in 69.4% of cases, whereas those administered from a sharp tip transmitted bacteria in only 22.2% of cases (P = 0.001). At an instillation angle of 45°, contamination was identified in 83.3% of bottles with a rounded tip geometry and in only eight of 18 bottles (44.4%) from those with a sharp nozzle geometry (P = 0.005). Conclusions: Adjusting the instillation angle of eyedrop solutions to 90°, as well as using a nozzle geometry that prevents flow of the solution to the side of the bottle, significantly reduced contamination rates. Translational Relevance: Standardizing drop bottles and adjusting delivery angle shows promise in reducing contamination rates and may critically impact the quality of care for patients requiring topical therapeutic agents.


Assuntos
Contaminação de Medicamentos , Lubrificantes Oftálmicos , Bactérias , Brasil , Humanos , Pseudomonas aeruginosa
19.
Talanta ; 206: 120219, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514888

RESUMO

A new method to determine the total titratable acidity of orange, lemon and passion fruit, based on a spot test obtained from digital images and using anthocyanins as the biodegradable indicator, is presented for the first time. The colorimetric reactions were carried out by acid-base titration on a microscale, employing anthocyanin with a microplate for spot test purposes, with detection by digital imaging. To obtain highly precise data, a chamber based on a diffuser was developed to control the illumination supplied by the light emitting diodes, and coupled to a smartphone to acquire adequate digital images. High precision was obtained with a relative standard deviation of 0.758% for n = 95. The RGB values were extracted from the digital images and used as analytical signals, the values being correlated with the micro-volume of the titrant and used to construct the titration curves and obtain the first and second derivatives, respectively. For comparative purposes, the official AOAC (Association of Official Analytical Chemists) and MAPA (Ministry of Agriculture, Livestock and Food Supply of Brazil) methods were used and the results compared by applying the paired t-test at the 95% confidence level (n = 3). No difference was found between the values and the relative errors were less than 2.8%. The micro-titrimetric method was fast, uses anthocyanins as the natural indicator, is practical, and permits a reduction of 922 times or 99.9% of the volume required in a conventional titration. It is therefore ideal for routine analyses leading to a reduction in the waste generated, according to the principles of green chemistry.


Assuntos
Citrus sinensis/química , Frutas/química , Passiflora/química , Antocianinas/química , Colorimetria/instrumentação , Colorimetria/métodos , Química Verde/métodos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Phaseolus/química , Smartphone , Titulometria/instrumentação , Titulometria/métodos
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