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1.
J Chem Inf Model ; 64(14): 5547-5556, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38938209

RESUMEN

Ultraviolet (UV) absorption spectroscopy is a widely used tool for quantitative and qualitative analyses of chemical compounds. In the gas phase, vacuum UV (VUV) and UV absorption spectra are specific and diagnostic for many small molecules. An accurate prediction of VUV/UV absorption spectra can aid the characterization of new or unknown molecules in areas such as fuels, forensics, and pharmaceutical research. An alternative to quantum chemical spectral prediction is the use of artificial intelligence. Here, different molecular feature representation techniques were used and developed to encode chemical structures for testing three machine learning models to predict gas-phase VUV/UV absorption spectra. Structure data files (.sdf) and VUV/UV absorption spectra for 1397 volatile and semivolatile chemical compounds were used to train and test the models. New molecular features (termed ABOCH) were introduced to better capture pi-bonding, aromaticity, and halogenation. The incorporation of these new features benefited spectral prediction and demonstrated superior performance compared to computationally intensive molecular-based deep learning methods. Of the machine learning methods, the use of a Random Forest regressor returned the best accuracy score with the shortest training time. The developed machine learning prediction model also outperformed spectral predictions based on the time-dependent density functional theory.


Asunto(s)
Gases , Aprendizaje Automático , Espectrofotometría Ultravioleta , Vacio , Espectrofotometría Ultravioleta/métodos , Gases/química , Rayos Ultravioleta
2.
J Appl Clin Med Phys ; 24(6): e13920, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36727606

RESUMEN

PURPOSE: To incorporate four-dimensional computed tomography (4DCT)-based ventilation imaging into intensity-modulated radiation therapy (IMRT) treatment planning for pulmonary functional avoidance. METHODS AND MATERIALS: Nineteen locally advanced lung cancer patients are retrospectively studied. 4DCT images are employed to create ventilation maps for each patient via a density-change-based algorithm with mass correction. The regional ventilation is directly incorporated into the mathematical formulation of a direct aperture optimization model in IMRT treatment planning to achieve functional avoidance and a voxel-based treatment plan. The proposed functional avoidance planning and voxel-based planning are compared to the conventional treatment planning approach purely based on the anatomy of patients. Paired sample t-tests are conducted to see whether dosimetric differences among the three approaches are significant. RESULTS: Similar planning target volume (PTV) coverage is achieved by anatomical, functional avoidance, and voxel-based approaches. The voxel-based treatment planning performs better than both functional avoidance and anatomical planning to the lung. For a total lung, the average volume reductions in a functional avoidance plan from an anatomical plan, a voxel-based plan from an anatomical plan, and a voxel-based plan from a functional avoidance plan are 7.0%, 16.8%, and 10.6%, respectively for V40 ; and 0.4%, 6.4%, and 6.0%, respectively for mean Lung Dose (MLD). For a functional lung, the reductions are 8.8%, 17.2%, and 9.2%, respectively, for fV40 ; and 1.1%, 6.2%, and 5.2%, respectively, for functional mean lung dose (fMLD). These reductions are obtained without significantly increasing doses to other organs-at-risk. All the pairwise treatment planning comparisons for both total lung and functional lung are statistically significant (p-value < α = 0.05 $< \alpha =0.05$ ) except for the functional avoidance plan with the anatomical plan pair in which the p-value > α = 0.05 $> \alpha =0.05$ . From these results, we can conclude that voxel-based treatment planning outperforms both anatomical and functional-avoidance planning. CONCLUSIONS: We propose a treatment planning framework that directly utilizes functional images and compares voxel-based treatment planning with functional avoidance and anatomical treatment planning.


Asunto(s)
Neoplasias Pulmonares , Radioterapia de Intensidad Modulada , Humanos , Tomografía Computarizada Cuatridimensional/métodos , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Pulmón/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia
3.
Environ Sci Pollut Res Int ; 31(11): 16735-16745, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38326682

RESUMEN

Sustainable mobility options such as electric vehicles (EVs) have the potential to improve the quality of life for Americans as well as those in other countries, as they can enhance the quality of the air we breathe, while reducing greenhouse gas emissions, fossil fuel consumption, and the adverse impacts of global warming. Despite their many benefits, however, the demand for EVs remains low. Therefore, this study aims to identify the barriers that affect the widespread EV adoption in the United States. Seventeen barriers were identified from the literature, and a questionnaire survey was designed and distributed to potential consumers of EVs. The survey yielded 733 responses, and various statistical tests like cluster analysis and chi-squared tests were performed. The results revealed that the high purchase price of the vehicle, high battery replacement cost, and the lack of public infrastructures for charging them were the primary concerns. The results also revealed that middle-aged men with high education and income are more enthusiastic about adopting EVs. The results presented in this study indicate a range of developments that different stakeholders could implement. To surmount the economic barriers to EV adoption, policymakers should strengthen incentives countrywide, and automakers should introduce more affordable EVs to the market. To overcome the challenges associated with charging, it is necessary to make investments in rapid charging infrastructure along the primary toll routes.


Asunto(s)
Gases de Efecto Invernadero , Emisiones de Vehículos , Persona de Mediana Edad , Estados Unidos , Humanos , Emisiones de Vehículos/análisis , Texas , Calidad de Vida , Motivación , Vehículos a Motor
4.
Traffic Inj Prev ; 23(6): 333-338, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35639637

RESUMEN

OBJECTIVES: On-demand ridesharing services are suggested to provide several benefits, such as improving accessibility and mobility, reducing drive-alone trips and greenhouse gas emissions. However, the impacts of these services on traffic crashes are not completely clear. This paper investigates the availability of Via- an on-demand ridesharing service in Arlington, TX, to identify the effects of this service on traffic crashes. We hypothesize that the launch of Via would result in more shared rides, fewer drive-alone trips and fewer traffic crashes. METHODS: We implement an Interrupted Time Series Analysis (ITSA) approach to study the impact of Via service availability on traffic crashes using weekly counts of all traffic crashes, the number of injuries, and serious injuries that occurred in Arlington from 2014 to 2021. RESULTS: The results show a statistically significant reduction in the weekly number of total crashes and total injuries but do not show any significant impact on the number of serious injuries. Shared Autonomous Vehicles have the potential to reduce traffic crashes caused by driver's fault. CONCLUSIONS: This study reveals the potential impacts ridesharing services can have on traffic crashes and injuries in a mid-sized city. The results of this study can help decision and policymakers to understand the full potential of ridesharing services that can contribute to making relevant decisions toward creating sustainable and safer transportation systems in cities.


Asunto(s)
Accidentes de Tránsito , Proyectos de Investigación , Accidentes de Tránsito/prevención & control , Ciudades , Humanos , Análisis de Series de Tiempo Interrumpido , Factores de Tiempo
5.
Comput Inform Nurs ; 28(1): 57-62, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-19940622

RESUMEN

This pilot program is a software-based prototype providing a nurse-to-patient assignment presented to two groups of RNs enrolled in a nursing research course in a North Texas university. The goal of the pilot program was to obtain input regarding the assessment, functionality, and practicality of a nurse-to-patient electronic prototype. Registered nurse students were given a presurvey, instructions, and details on the use of the prototype, followed by a postsurvey. Prototype speed and lack of bias were reported as most favorable. Registered nurse students requested additions of multiple diagnoses, patient acuity, and experience level of the nurse to enhance the prototype. Seventy-three percent (n = 24) of the participants said that they would use the prototype, and 15% (n = 5) said that they would not.


Asunto(s)
Sistemas de Información en Hospital , Relaciones Enfermero-Paciente , Personal de Enfermería en Hospital , Admisión y Programación de Personal , Carga de Trabajo
6.
Am J Trop Med Hyg ; 93(1): 114-22, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25940194

RESUMEN

Visceral leishmaniasis (VL) is the most deadly form of the leishmaniasis family of diseases, which affects numerous developing countries. The Indian state of Bihar has the highest prevalence and mortality rate of VL in the world. Insecticide spraying is believed to be an effective vector control program for controlling the spread of VL in Bihar; however, it is expensive and less effective if not implemented systematically. This study develops and analyzes a novel optimization model for VL control in Bihar that identifies an optimal (best possible) allocation of chosen insecticide (dichlorodiphenyltrichloroethane [DDT] or deltamethrin) based on the sizes of human and cattle populations in the region. The model maximizes the insecticide-induced sandfly death rate in human and cattle dwellings while staying within the current state budget for VL vector control efforts. The model results suggest that deltamethrin might not be a good replacement for DDT because the insecticide-induced sandfly deaths are 3.72 times more in case of DDT even after 90 days post spray. Different insecticide allocation strategies between the two types of sites (houses and cattle sheds) are suggested based on the state VL-control budget and have a direct implication on VL elimination efforts in a resource-limited region.


Asunto(s)
DDT/uso terapéutico , Vivienda para Animales , Vivienda , Control de Insectos/métodos , Insectos Vectores , Insecticidas/uso terapéutico , Leishmaniasis Visceral/prevención & control , Nitrilos/uso terapéutico , Psychodidae , Piretrinas/uso terapéutico , Animales , Bovinos , Simulación por Computador , DDT/economía , Humanos , India , Control de Insectos/economía , Nitrilos/economía , Piretrinas/economía , Asignación de Recursos
7.
Health Care Manag Sci ; 13(3): 210-21, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20715305

RESUMEN

The health care system in the United States has a shortage of nurses. A careful planning of nurse resources is needed to ease the health care system from the burden of the nurse shortage and standardize nurse workload. An earlier research study developed a data-integrated simulation to evaluate nurse-patient assignments (SIMNA) at the beginning of a shift based on a real data set provided by a northeast Texas hospital. In this research, with the aid of the same SIMNA model, two policies are developed to make nurse-to-patient assignments when new patients are admitted during a shift. A heuristic (HEU) policy assigns a newly-admitted patient to the nurse who has performed the least assigned direct care among all the nurses. A partially-optimized (OPT) policy seeks to minimize the difference in workload among nurses for the entire shift by estimating the assigned direct care from SIMNA. Results comparing HEU and OPT policies are presented.


Asunto(s)
Personal de Enfermería en Hospital/organización & administración , Admisión del Paciente , Admisión y Programación de Personal , Algoritmos , Humanos , Personal de Enfermería en Hospital/provisión & distribución , Estados Unidos
8.
Health Care Manag Sci ; 12(3): 252-68, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19739359

RESUMEN

This research develops a novel data-integrated simulation to evaluate nurse-patient assignments (SIMNA) based on a real data set provided by a northeast Texas hospital. Tree-based models and kernel density estimation (KDE) were utilized to extract important knowledge from the data for the simulation. Classification and Regression Tree models, data mining tools for prediction and classification, were used to develop five tree structures: (a) four classification trees from which transition probabilities for nurse movements are determined, and (b) a regression tree from which the amount of time a nurse spends in a location is predicted based on factors such as the primary diagnosis of a patient and the type of nurse. Kernel density estimation is used to estimate the continuous distribution for the amount of time a nurse spends in a location. Results obtained from SIMNA to evaluate nurse-patient assignments in Medical/Surgical unit I of the northeast Texas hospital are discussed.


Asunto(s)
Personal de Enfermería en Hospital/organización & administración , Sistemas de Información para Admisión y Escalafón de Personal , Admisión y Programación de Personal/organización & administración , Árboles de Decisión , Humanos , Modelos Teóricos
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