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1.
Sci Rep ; 14(1): 6823, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38514729

RESUMO

The demand for measuring fluorophore temperature sensitivity and temperature change in chemical or biological samples has spurred the search for effective methods. While infrared (IR) light-based thermal devices are popular, they are limited to surface temperature measurement. Fluorescence-based thermometry, which utilizes intensity, lifetime, polarization, and spectrum change, provides the temperature information directly from the samples and can have high temporal and spatial resolution. However, measuring fluorescence can be tricky and expensive. A cost-effective approach to achieving reasonable accuracy is highly desired. This study introduces such an approach, employing a light-emitting diode (LED) for fluorophore excitation and a laser diode (LD) for sample heating, with a phone camera recording fluorescence changes. A data processing method converts the video into digital data, processed through digital filters. Utilizing a small-volume cuvette enhances heating efficiency. This study serves as a practical guide for inexperienced individuals, including students, instructors, and researchers, facilitating entry into the field and navigating the complexities of fluorescence-based thermometry.

3.
Radiother Oncol ; 170: 95-101, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35259416

RESUMO

INTRODUCTION: In stage III non-small cell lung cancer (NSCLC), prophylactic cranial irradiation (PCI) reduces the brain metastases incidence and prolongs the progression-free survival without improving overall survival. PCI increases the risk of toxicity and is currently not adopted in routine care. Our objective was to assess the cost-effectiveness of PCI compared with no PCI in stage III NSCLC from a Dutch societal perspective. METHODS: A cohort partitioned survival model was developed based on individual patient data from three randomized phase III trials (N = 670). Quality-adjusted life years (QALYs) and costs were estimated over a lifetime time horizon. A willingness-to-pay (WTP) threshold of €80,000 per QALY was adopted. Sensitivity and scenario analyses were performed to address parameter uncertainty and to explore what parameters had the greatest impact on the cost-effectiveness results. RESULTS: PCI was more effective and costly (0.443 QALYs, €10,123) than no PCI, resulting in an incremental cost-effectiveness ratio (ICER) of €22,843 per QALY gained. The probability of PCI being cost-effective at a WTP threshold of €80,000 per QALY was 93%. The probability of PCI gaining three and six additional months of life were 76% and 56%. The scenario analysis adding durvalumab increased the ICER to €35,159 per QALY gained. Using alternative survival distributions had little impact on the ICER. Assuming fewer PCI fractions and excluding indirect costs decreased the ICER to €18,263 and €5554 per QALY gained. CONCLUSION: PCI is cost-effective compared to no PCI in stage III NSCLC, and could therefore, from a cost-effectiveness perspective, be considered in routine care.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Análise Custo-Benefício , Irradiação Craniana , Humanos , Anos de Vida Ajustados por Qualidade de Vida
4.
Sens Actuators B Chem ; 235: 126-135, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27725788

RESUMO

Cellular phone penetration has grown continually over the past two decades with the number of connected devices rapidly approaching the total world population. Leveraging the worldwide ubiquity and connectivity of these devices, we developed a mobile phone-based electrochemical biosensor platform for point-of-care (POC) diagnostics and wellness tracking. The platform consists of an inexpensive electronic module (< $20) containing a low-power potentiostat that interfaces with and efficiently harvests power from a wide variety of phones through the audio jack. Active impedance matching improves the harvesting efficiency to 79%. Excluding loses from supply rectification and regulation, the module consumes 6.9 mW peak power and can measure < 1 nA bidirectional current. The prototype was shown to operate within the available power budget set by mobile devices and produce data that matches well with that of an expensive laboratory grade instrument. We demonstrate that the platform can be used to track the concentration of secretory leukocyte protease inhibitor (SLPI), a biomarker for monitoring lung infections in cystic fibrosis patients, in its physiological range via an electrochemical sandwich assay on disposable screen-printed electrodes with a 1 nM limit of detection.

5.
J Environ Manage ; 165: 188-198, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26433360

RESUMO

This work presents an optimization framework for evaluating different wastewater treatment/disposal options for water management during hydraulic fracturing (HF) operations. This framework takes into account both cost-effectiveness and system uncertainty. HF has enabled rapid development of shale gas resources. However, wastewater management has been one of the most contentious and widely publicized issues in shale gas production. The flowback and produced water (known as FP water) generated by HF may pose a serious risk to the surrounding environment and public health because this wastewater usually contains many toxic chemicals and high levels of total dissolved solids (TDS). Various treatment/disposal options are available for FP water management, such as underground injection, hazardous wastewater treatment plants, and/or reuse. In order to cost-effectively plan FP water management practices, including allocating FP water to different options and planning treatment facility capacity expansion, an optimization model named UO-FPW is developed in this study. The UO-FPW model can handle the uncertain information expressed in the form of fuzzy membership functions and probability density functions in the modeling parameters. The UO-FPW model is applied to a representative hypothetical case study to demonstrate its applicability in practice. The modeling results reflect the tradeoffs between economic objective (i.e., minimizing total-system cost) and system reliability (i.e., risk of violating fuzzy and/or random constraints, and meeting FP water treatment/disposal requirements). Using the developed optimization model, decision makers can make and adjust appropriate FP water management strategies through refining the values of feasibility degrees for fuzzy constraints and the probability levels for random constraints if the solutions are not satisfactory. The optimization model can be easily integrated into decision support systems for shale oil/gas lifecycle management.


Assuntos
Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluição da Água/análise , Monitoramento Ambiental , Fraturamento Hidráulico , Modelos Teóricos , Reprodutibilidade dos Testes , Incerteza , Água , Poluentes Químicos da Água/química , Purificação da Água/economia , Purificação da Água/métodos
6.
IEEE Trans Biomed Circuits Syst ; 10(5): 945-954, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-28113176

RESUMO

This paper describes the design and characterization of a reconfigurable, multi-technique electrochemical biosensor designed for direct integration into smartphone and wearable technologies to enable remote and accurate personal health monitoring. By repurposing components from one mode to the next, the biosensor's potentiostat is able reconfigure itself into three different measurements modes to perform amperometric, potentiometric, and impedance spectroscopic tests all with minimal redundant devices. A [Formula: see text] PCB prototype of the module was developed with discrete components and tested using Google's Project Ara modular smartphone. The amperometric mode has a ±1 nA to [Formula: see text] measurement range. When used to detect pH, the potentiometric mode achieves a resolution of < 0.08 pH units. In impedance measurement mode, the device can measure 50 Ω-10 [Formula: see text] and has been shown to have of phase error. This prototype was used to perform several point-of-care health tracking assays suitable for use with mobile devices: 1) Blood glucose tests were conducted and shown to cover the diagnostic range for Diabetic patients (  âˆ¼  200 mg/dL). 2) Lactoferrin, a biomarker for urinary tract infections, was detected with a limit of detection of approximately 1 ng/mL. 3) pH tests of sweat were conducted to track dehydration during exercise. 4) EIS was used to determine the concentration of NeutrAvidin via a label-free assay.


Assuntos
Técnicas Biossensoriais/instrumentação , Condutometria/instrumentação , Diagnóstico por Computador/instrumentação , Autocuidado/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Smartphone , Telemedicina/instrumentação , Amplificadores Eletrônicos , Desenho de Equipamento , Análise de Falha de Equipamento , Monitorização Ambulatorial/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Integração de Sistemas
7.
IEEE Biomed Circuits Syst Conf ; 2014: 312-315, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26097899

RESUMO

This paper describes the development of a smartphone-based electrochemical biosensor module. The module contains a low power potentiostat that interfaces and harvests power from a smartphone through the phone's audio jack. A prototype with two different potentiostat designs was constructed and used to conduct proof of concept cyclic voltammetry experiments with potassium ferro-/ferricyanide (K4[Fe(CN)6] / K3[Fe(CN)6]) in a side-by-side comparison with a laboratory grade instrument. Results show that the module functions within the available power budget and that the recovered voltammogram data matches well with the data from an expensive bench top tool. Excluding the loses from supply rectification and regulation, the module consumes either 5.7 mW or 4.3 mW peak power, depending on which of the two discussed potentiostat designs is used. At single quantity pricing, the hardware for the prototype device costs less than $30.

8.
Clin Lung Cancer ; 14(2): 108-12, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22885348

RESUMO

BACKGROUND: Comprehensive and accurate assessment of symptoms experienced by patients undergoing lung radiotherapy (RT) is challenging. This study aims to evaluate the feasibility and utility of collecting acute toxicity information by using a patient-reported instrument, the Thoracic Symptom Self-Assessment Tool (TSSAT). METHODS: The TSSAT is based on the CTCAE v3.0(Common Toxicity Criteria of Adverse Events). All patients undergoing lung RT at our center from May 2008 to April 2009 were asked to complete the TSSAT on day 1 and weekly during RT. TSSAT scores were compared with clinician reporting of the same symptoms. Descriptive statistics and weighted kappa values were calculated to measure the agreement between patient- and clinician-reported acute toxicity. RESULTS: Of 300 consecutive patients approached, 49% (148/300) completed the TSSAT at least once. Patient participation and compliance were associated with treatment intent; radical (87%) vs. palliative (25%); P = <.0001. The average data completion rate by patients was 72%, and the average toxicity documentation rate by clinicians was 67%. Agreement between patients and clinicians was fair to moderate for most symptoms; the majority (>79%) of the differences were within one grade. Patients reported greater severity than clinicians for subjective symptoms. Clinicians graded greater severity than patients for the more observable symptoms. CONCLUSIONS: The TSSAT has been shown to be feasible and accepted by patients receiving radical dose RT. Patient-reported assessments may improve acute symptom management in the future.


Assuntos
Neoplasias Pulmonares/radioterapia , Autoavaliação (Psicologia) , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia/efeitos adversos
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