299 research outputs found

    Classification of burn injuries using near-infrared spectroscopy.

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    Early surgical management of those burn injuries that will not heal spontaneously is critical. The decision to excise and graft is based on a visual assessment that is often inaccurate but yet continues to be the primary means of grading the injury. Superficial and intermediate partial-thickness injuries generally heal with appropriate wound care while deep partial- and full-thickness injuries generally require surgery. This study explores the possibility of using near-infrared spectroscopy to provide an objective and accurate means of distinguishing shallow injuries from deeper burns that require surgery. Twenty burn injuries are studied in five animals, with burns covering <1% of the total body surface area. Carefully controlled superficial, intermediate, and deep partial-thickness injuries as well as full-thickness injuries could be studied with this model. Near-infrared reflectance spectroscopy was used to evaluate these injuries 1 to 3 hours after the insult. A probabilistic model employing partial least-squares logistic regression was used to determine the degree of injury, shallow (superficial or intermediate partial) from deep (deep partial and full thickness), based on the reflectance spectrum of the wound. A leave-animal-out cross-validation strategy was used to test the predictive ability of a 2-latent variable, partial least-squares logistic regression model to distinguish deep burn injuries from shallow injuries. The model displayed reasonable ranking quality as summarized by the area under the receiver operator characteristics curve, AUC = 0.879. Fixing the threshold for the class boundaries at 0.5 probability, the model sensitivity (true positive fraction) to separate deep from shallow burns was 0.90, while model specificity (true negative fraction) was 0.83. Using an acute porcine model of thermal burn injuries, the potential of near-infrared spectroscopy to distinguish between shallow healing burns and deeper burn injuries was demonstrated. While these results should be considered as preliminary and require clinical validation, a probabilistic model capable of differentiating these classes of burns would be a significant aid to the burn specialist

    Evaluation of Artificial Lighting Sources for the Acquisition of Color Infrared Imagery Under Glasshouse Conditions

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    English: Research was conducted to evaluate the spectral properties, illumination intensities and lighting patterns of four basic categories of bulbs and lamps which could conceivably serve as sole lighting sources for the acquisition of color infrared (CIR) imagery under glasshouse conditions. Bulbs and lamps in two major categories (fluorescent tubes and sodium- and mercury-vapor glasshouse lamps) were deemed unsuitable for this purpose either because they emitted little or no nearinfrared (NIR) radiation or because they imparted an overall bluish cast that seriously degraded the quality of CIR imagery. All of the incandescent and quartz halogen lamps evaluated in these studies exhibited spectral properties suitable for CIR image acquisition, i.e., they emitted relatively high levels of both visible and NIR radiation. However, most bulbs and lamps in these categories were characterized by either inadequate levels of illumination or reflectors that produced a circular lighting pattern in which luminosity varied substantially from the center portion of the image to the edges. The most suitable bulb evaluated was a heavy-duty (500W) quartz halogen lamp with a rectangular reflector which, when modified by the addition of crumpled aluminum foil to the reflector housing, produced adequate levels of illumination that was distributed in a near-uniform pattern across the target area. Color infrared imagery of plant foliage acquired using this lamp as a sole lighting source was comparable in quality to imagery of the same plant material acquired under natural lighting conditions. The performance of this particular lamp is used to exemplify the stringent requirements of any lamp under consideration as a sole lighting source for CIR image acquisition within the glasshouse environment. Spanish: Se investigaron las propiedades espectrales, las intensidades de iluminación y los patrones de luz de cuatro tipos básicos de bulbos y lámparas que podrían servir como fuentes únicas de luz para la adquisición de imágenes infrarrojas (CIR) bajo condiciones de invernadero. No se consideraron adecuados para este propósito los bulbos y las lámparas en dos categorías importantes (tubos de fluorescencia y lámparas de invernadero de vapor de mercurio y sodio ya que o emitieron muy poca o ninguna radiación infrarroja cercana (NIR) o porque impartieron un tono azul que degradó seriamente la calidad de las imágenes CIR. Todas las lámparas incandescentes y de halógeno de cuarzo evaluadas en estos estudios exhibieron propiedades espectrales adecuadas para la adquisición de imágenes infrarrojas, por ejemplo, emitieron niveles relativamente altos de radiación visible y de radiación cercana al infrarrojo. Sin embargo, las mayoría de los bulbos y lámparas en esta categoría se caracterizaron por producir niveles inadecuados de iluminación o por producir un patrón de luz circular en el cual la luminosidad varió substancialmente de la porción central de la imagen a las orillas. El bulbo probado que resultó mas adecuado fue la lámpara de halógeno-cuarzo con un reflector rectangular el cual, cuando se modificó por la adición de papel aluminio arrugado al nicho del reflector, produjo niveles adecuados de iluminación que se distribuyeron en un patrón casi uniforme a lo largo de la área expuesta. Las imágenes infrarrojas del follaje vegetal tomadas usando esta lámpara como única fuente de luz fueron comparables en calidad a las imágenes del mismo follaje tomadas bajo condiciones de luz natural. El desempeño de esta lámpara en particular es usado para ejemplificar los estrictos requerimientos para cualquier lámpara que sea usada como única fuente de luz para la adquisición de imágenes de color infrarrojo en ambiente de invernadero

    Impacts of active school design on schooltime sedentary behavior and physical activity: A pilot natural experiment

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    Background Children spend a significant portion of their days in sedentary behavior (SB) and on average fail to engage in adequate physical activity (PA). The school built environment may influence SB and PA, but research is limited. This natural experiment evaluated whether an elementary school designed to promote movement impacted students\u27 school-time SB and PA. Methods Accelerometers measured SB and PA at pre and post time-points in an intervention group who moved to the new school (n = 21) and in a comparison group experiencing no school environmental change (n = 20). Difference-in-difference (DD) analysis examined SB and PA outcomes in these groups. Measures were also collected post-intervention from an independent, grade-matched group of students in the new school (n = 21). Results As expected, maturational increases in SB were observed. However, DD analysis estimated that the intervention attenuated increase in SB by 81.2 ± 11.4 minutes/day (p\u3c0.001), controlling for time in moderate to vigorous physical activity (MVPA). The intervention was also estimated to increase daily number of breaks from SB by 23.4 ± 2.6 (p \u3c .001) and to increase light physical activity (LPA) by 67.7 ± 10.7 minutes/day (p\u3c0.001). However, the intervention decreased MVPA by 10.3 ± 2.3 minutes/day (p\u3c0.001). Results of gradematched independent samples analysis were similar, with students in the new vs. old school spending 90.5 ± 16.1 fewer minutes/day in SB, taking 21.1 ± 2.7 more breaks from SB (p\u3c0.001), and spending 64.5 ± 14.8 more minutes in LPA (p\u3c0.001), controlling for time in MVPA. Students in the new school spent 13.1 ± 2.7 fewer minutes in MVPA (p\u3c0.001) than their counterparts in the old school. Conclusions This pilot study found that active school design had beneficial effects on SB and LPA, but not on MVPA. Mixed results point to a need for active classroom design strategies to mitigate SB, and quick access from classrooms to areas permissive of high-intensity activities to promote MVPA. Integrating active design with programs/policies to promote PA may yield greatest impact on PA of all intensities

    The roasting process and place of cultivation influence the volatile fingerprint of Criollo cocoa from Amazonas, Peru

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    The Criollo cocoa bean is classified as “fine” or flavor cocoas, being perceived as aromatic or smooth with fruity, raisin, floral, spicy, nutty, molasses, and caramel notes. In the present work, gas chromatography coupled to mass spectrometry was used to study the volatile fingerprint of roasted and unroasted Criollo cocoa from four Amazon districts: Nieva, Cajaruro, Copallín and La Peca located in the Amazon Region of Peru. The results showed that the main sensory perception of cocoa is fruit, and this decreases as the roasting intensity increases. A total of 96 volatile compounds were found, of which the esters had a greater presence in the volatile fingerprint of Criollo cocoa. Propyl acetate (3.5%), acetoin acetate (1.3%) and diethyl succinate (0.8%) were found as the characteristic compounds of Criollo cocoa analyzed, which give it its fruit perception. The linalool/benzaldehyde ratio was between 0.56 and 0.89 for La Peca and Cajaruro cocoa. Principal component analysis revealed that the Criollo cocoa in each district has a different volatile fingerprint, whether it is roasted or unroasted beans. The roasting process generates a greater differentiation of the volatile fingerprint of Criollo cocoa

    Cumulative Burden of Morbidity Among Testicular Cancer Survivors After Standard Cisplatin-Based Chemotherapy: A Multi-Institutional Study

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    Purpose In this multicenter study, we evaluated the cumulative burden of morbidity (CBM) among > 1,200 testicular cancer survivors and applied factor analysis to determine the co-occurrence of adverse health outcomes (AHOs). Patients and Methods Participants were ≤ 55 years of age at diagnosis, finished first-line chemotherapy ≥ 1 year previously, completed a comprehensive questionnaire, and underwent physical examination. Treatment data were abstracted from medical records. A CBM score encompassed the number and severity of AHOs, with ordinal logistic regression used to assess associations with exposures. Nonlinear factor analysis and the nonparametric dimensionality evaluation to enumerate contributing traits procedure determined which AHOs co-occurred. Results Among 1,214 participants, approximately 20% had a high (15%) or very high/severe (4.1%) CBM score, whereas approximately 80% scored medium (30%) or low/very low (47%). Increased risks of higher scores were associated with four cycles of either ifosfamide, etoposide, and cisplatin (odds ratio [OR], 1.96; 95% CI, 1.04 to 3.71) or bleomycin, etoposide, and cisplatin (OR, 1.44; 95% CI, 1.04 to 1.98), older attained age (OR, 1.18; 95% CI, 1.10 to 1.26), current disability leave (OR, 3.53; 95% CI, 1.57 to 7.95), less than a college education (OR, 1.44; 95% CI, 1.11 to 1.87), and current or former smoking (OR, 1.28; 95% CI, 1.02 to 1.63). CBM score did not differ after either chemotherapy regimen ( P = .36). Asian race (OR, 0.41; 95% CI, 0.23 to 0.72) and vigorous exercise (OR, 0.68; 95% CI, 0.52 to 0.89) were protective. Variable clustering analyses identified six significant AHO clusters (χ2 P < .001): hearing loss/damage, tinnitus (OR, 16.3); hyperlipidemia, hypertension, diabetes (OR, 9.8); neuropathy, pain, Raynaud phenomenon (OR, 5.5); cardiovascular and related conditions (OR, 5.0); thyroid disease, erectile dysfunction (OR, 4.2); and depression/anxiety, hypogonadism (OR, 2.8). Conclusion Factors associated with higher CBM may identify testicular cancer survivors in need of closer monitoring. If confirmed, identified AHO clusters could guide the development of survivorship care strategies

    Post-concussive symptoms mediate the relationship between sleep problems and participation restrictions among veterans with mild traumatic brain injury

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    BackgroundSleep problems are common among Veterans with mild traumatic brain injury (mTBI) and may contribute to participation restrictions. However, explanatory mechanisms underlying this relationship are poorly understood. Sleep problems are associated with post-concussive symptoms (e.g., headaches). In turn, post-concussive symptoms contribute to participation restrictions. We hypothesized that post-concussive symptom severity mediates the purported relationship between sleep problems and participation restrictions among Veterans with mTBI.Materials and MethodsThis study was a retrospective analysis of clinical data among 8,733 Veterans with mTBI receiving Veterans Health Administration outpatient care. Sleep problems (yes/no) were identified using the sleep-related item from the Neurobehavioral Symptom Inventory (NSI). Post-concussive symptoms were measured using remaining NSI items. Participation restrictions were measured using the Mayo-Portland Adaptability Inventory Participation Index. We specified a latent variable path model to estimate relationships between: (1) sleep problems and three latent indicators of post-concussive symptoms [vestibular-sensory (e.g., headache)]; mood-behavioral [e.g., anxiety]; cognitive [e.g., forgetfulness]); and, (2) the three latent indicators of post-concussive symptoms and two latent indicators of participation restrictions (social and community participation [e.g., leisure activities]; productivity [e.g., financial management]). We examined the indirect effects of sleep problems upon participation restrictions, as mediated by post-concussive symptoms. Estimates were adjusted for sociodemographic factors (e.g., age), injury characteristics (e.g., blast), and co-morbid conditions (e.g., depression).Results87% of Veterans reported sleep problems. Sleep problems were associated with greater social and community participation restrictions, as mediated by mood-behavioral (β = 0.41, p &lt; 0.001) and cognitive symptoms (β = 0.13, p &lt; 0.001). There was no evidence that vestibular-sensory symptoms mediated this relationship (β = -0.01, p = 0.48). Sleep problems were associated with greater productivity restrictions, as mediated by vestibular-sensory (β = 0.16, p &lt; 0.001) and cognitive symptoms (β = 0.14, p &lt; 0.001). There was no evidence that mood-behavioral symptoms mediated this relationship (β = 0.02, p = 0.37).DiscussionFindings suggest that evidence-based sleep treatment should occupy a prominent role in the rehabilitation of Veterans with mTBI. Indirect effects of sleep problems differed when considering impact on social and community participation vs. productivity, informing individualized rehabilitative care for Veterans with mTBI

    A Targeted Conservation Approach for Improving Environmental Quality: Multiple Benefits and Expanded Opportunities

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    Find out how targeted conservation practices can have the most impact on environmental quality while causing only a small change in overall agricultural production. Environmental benefits are discussed related to clean air and water, productive soils, diverse wildlife and plant habitat, and biological controls for crop protection.https://lib.dr.iastate.edu/extension_ag_pubs/1084/thumbnail.jp
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