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1.
Anal Chem ; 89(5): 3177-3183, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28264570

RESUMO

Morphological changes in U3O8 based on calcination temperature have been quantified enabling a morphological feature to serve as a signature of processing history in nuclear forensics. Five separate calcination temperatures were used to synthesize α-U3O8, and each sample was characterized using powder X-ray diffraction (p-XRD) and scanning electron microscopy (SEM). The p-XRD spectra were used to evaluate the purity of the synthesized U-oxide; the morphological analysis for materials (MAMA) software was utilized to quantitatively characterize the particle shape and size as indicated by the SEM images. Analysis comparing the particle attributes, such as particle area at each of the temperatures, was completed using the Kolmogorov-Smirnov two sample test (K-S test). These results illustrate a distinct statistical difference between each calcination temperature. To provide a framework for forensic analysis of an unknown sample, the sample distributions at each temperature were compared to randomly selected distributions (100, 250, 500, and 750 particles) from each synthesized temperature to determine if they were statistically different. It was found that 750 particles were required to differentiate between all of the synthesized temperatures with a confidence interval of 99.0%. Results from this study provide the first quantitative morphological study of U-oxides, and reveals the potential strength of morphological particle analysis in nuclear forensics by providing a framework for a more rapid characterization of interdicted uranium oxide samples.

2.
Addict Disord Their Treat ; 15(4): 149-156, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28503100

RESUMO

BACKGROUND: Technology-assisted treatment (TAT) can be an effective supplement to established face-to-face therapy modalities with a growing literature in substance use disorder (SUD) treatment. TAT access, interest, and familiarity are potential limitations to the use and efficacy of these approaches to treatment. METHODS: 174 participants in outpatient SUD treatment were administered a survey regarding technology device and Internet access, and interest in engaging in TAT SUD counseling (SUDC). The group was dichotomized by mean age and gender to examine potential variations in in these subgroups. RESULTS: Forty-three (43%) of participants were female, and the mean age was 44.8 years, and 89% of participants had Internet access. 83% of participants were interested in TAT for SUD counseling; 81% expected it to be at least "moderately helpful." 34% of participants noted they would choose to continue face-to-face therapy exclusively. 91% of participants had cell phones, but only 50% could access data or the Internet via their handheld device. 80% of participants stated they would be interested in trying SUDC via their phone. Women had a higher preference for computer-based SUDC than men, with gender being significantly correlated with TAT perceive helpfulness. CONCLUSION: These findings suggest that patients in outpatient SUD treatment have access to resources for TAT implementation, although access was not always readily available. Future research will be needed to determine whether the technology that this population possesses will be able to support the evolving TAT modalities and whether interest in TAT across age and gender groups equalizes over time.

3.
Psychosomatics ; 55(5): 450-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25016352

RESUMO

BACKGROUND: The field of psychosomatic medicine/consultation-liaison psychiatry, now a subspecialty in psychiatry, has focused its efforts on clinical care, education, and research at the interface of psychiatry, medicine, and neurology. OBJECTIVE: We sought to categorize characteristics and trends (over the past decade) in several journals intended primarily for practitioners of psychosomatic medicine. METHODS: We reviewed all articles published in 3 peer-reviewed journals (i.e., Psychosomatics, General Hospital Psychiatry, and the Journal of Psychosomatic Research) in 2002 and 2012. RESULTS: Each of the 3 journals has a different approach to publication of original research, clinical reviews, and case reports. CONCLUSIONS: The 3 journals demonstrate differing levels of international involvement, publish a different number of articles of different types (e.g., case reports, reviews, and original research), and focus on different types of medical-psychiatric problems.


Assuntos
Bibliometria , Revisão da Pesquisa por Pares , Publicações Periódicas como Assunto , Medicina Psicossomática , Editoração/tendências , Humanos
4.
ACS Omega ; 6(12): 8605-8615, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33817521

RESUMO

The hydration and morphological effects of amorphous (A)-UO3 following storage under varying temperature and relative humidity have been investigated. This study provides valuable insight into U-oxide speciation following aging, the U-oxide quantitative morphological data set, and, overall, the characterization of nuclear material provenance. A-UO3 was synthesized via the washed uranyl peroxide synthetic route and aged based on a 3-factor circumscribed central composite design of experiment. Target aging times include 2.57, 7.00, 14.0, 21.0, and 25.4 days, temperatures of 5.51, 15.0, 30.0, 45.0, and 54.5 °C, and relative humidities of 14.2, 30.0, 55.0, 80.0, and 95.8% were examined. Following aging, crystallographic changes were quantified via powder X-ray diffraction and an internal standard Rietveld refinement method was used to confirm the hydration of A-UO3 to crystalline schoepite phases. The particle morphology from scanning electron microscopy images was quantified using both the Morphological Analysis of MAterials software and machine learning. Results from the machine learning were processed via agglomerative hierarchical clustering analysis to distinguish trends in morphological attributes from the aging study. Significantly hydrated samples were found to have a much larger, plate-like morphology in comparison to the unaged controls. Predictive modeling via a response surface methodology determined that while aging time, temperature, and relative humidity all have a quantifiable effect on A-UO3 crystallographic and morphological changes, relative humidity has the most significant impact.

5.
Talanta ; 186: 433-444, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784384

RESUMO

The use of a limited set of signatures in nuclear forensics and nuclear safeguards may reduce the discriminating power for identifying unknown nuclear materials, or for verifying processing at existing facilities. Nuclear proliferomics is a proposed new field of study that advocates for the acquisition of large databases of nuclear material properties from a variety of analytical techniques. As demonstrated on a common uranium trioxide polymorph, α-UO3, in this paper, nuclear proliferomics increases the ability to improve confidence in identifying the processing history of nuclear materials. Specifically, α-UO3 was investigated from the calcination of unwashed uranyl peroxide at 350, 400, 450, 500, and 550 °C in air. Scanning electron microscopy (SEM) images were acquired of the surface morphology, and distinct qualitative differences are presented between unwashed and washed uranyl peroxide, as well as the calcination products from the unwashed uranyl peroxide at the investigated temperatures. Differential scanning calorimetry (DSC), UV-Vis spectrophotometry, powder X-ray diffraction (p-XRD), and thermogravimetric analysis-mass spectrometry (TGA-MS) were used to understand the source of these morphological differences as a function of calcination temperature. Additionally, the SEM images were manually segmented using Morphological Analysis for MAterials (MAMA) software to identify quantifiable differences in morphology for three different surface features present on the unwashed uranyl peroxide calcination products. No single quantifiable signature was sufficient to discern all calcination temperatures with a high degree of confidence; therefore, advanced statistical analysis was performed to allow the combination of a number of quantitative signatures, with their associated uncertainties, to allow for complete discernment by calcination history. Furthermore, machine learning was applied to the acquired SEM images to demonstrate automated discernment with at least 89% accuracy.

6.
Talanta ; 176: 284-292, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917753

RESUMO

The analytical techniques typically utilized in a nuclear forensic investigation often provide limited information regarding the process history and production conditions of interdicted nuclear material. In this study, scanning electron microscopy (SEM) analysis of the surface morphology of amorphous-UO3 samples calcined at 250, 300, 350, 400, and 450°C from uranyl peroxide was performed to determine if the morphology was indicative of the synthesis route and thermal history for the samples. Thermogravimetic analysis-mass spectrometry (TGA-MS) and differential scanning calorimetry (DSC) were used to correlate transitions in the calcined material to morphological transformations. The high-resolution SEM images were processed using the Morphological Analysis for Material Attribution (MAMA) software. Morphological attributes, particle area and circularity, indicated significant trends as a result of calcination temperature. The quantitative morphological analysis was able to track the process of particle fragmentation and subsequent sintering as calcination temperature was increased. At the 90% confidence interval, with 1000 segmented particles, the use of Kolmogorov-Smirnov statistical comparisons allowed discernment between all calcination temperatures for the uranyl peroxide route.

7.
Am J Physiol Gastrointest Liver Physiol ; 294(2): G576-88, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18096610

RESUMO

Junctional adhesion molecule (JAM) is involved in tight junction (TJ) formation in epithelial cells. Three JAMs (A, B, and C) are expressed in rat hepatocytes, but only rat JAM-A is present in polarized WIF-B cells, a rat-human hepatic line. We used knockdown (KD) and overexpression in WIF-B cells to determine the role of JAM-A in the development of hepatic polarity. Expression of rat JAM-A short hairpin RNA resulted in approximately 50% KD of JAM-A and substantial loss of hepatic polarity, as measured by the absence of apical cysts formed by adjacent cells and sealed by TJ belts. When inhibitory RNA-resistant human JAM-A (huWT) was expressed in KD cells, hepatic polarity was restored. In contrast, expression of JAM-A that either lacked its PDZ-binding motif (huDeltaC-term) or harbored a point mutation (T273A) did not complement, indicating that multiple sites within JAM-A's cytoplasmic tail are required for the development of hepatic polarity. Overexpression of huWT in normal WIF-B cells unexpectedly blocked WIF-B maturation to the hepatic phenotype, as did expression of three huJAM-A constructs with single point mutations in putative phosphorylation sites. In contrast, huDeltaC-term was without effect, and the T273A mutant only partially blocked maturation. Our results show that JAM-A is essential for the development of polarity in cultured hepatic cells via its possible phosphorylation and recruitment of relevant PDZ proteins and that hepatic polarity is achieved within a narrow range of JAM-A expression levels. Importantly, formation/maintenance of TJs and the apical domain in hepatic cells are linked, unlike simple epithelia.


Assuntos
Moléculas de Adesão Celular/fisiologia , Polaridade Celular/genética , Polaridade Celular/fisiologia , Hepatócitos/fisiologia , Imunoglobulinas/fisiologia , Sequência de Aminoácidos , Animais , Moléculas de Adesão Celular/genética , Linhagem Celular , Citoplasma/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Imunoglobulinas/genética , Lentivirus/genética , Dados de Sequência Molecular , Fosforilação , Plasmídeos/genética , Proteína Quinase C/metabolismo , Ratos , Receptores de Superfície Celular , Treonina/metabolismo , Transdução Genética
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