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91.
Applying terrestrial lidar for evaluation and calibration of airborne lidar-derived shrub biomass estimates in Arctic tundra 总被引:1,自引:0,他引:1
Heather E. Greaves Lee A. Vierling Jan U. H. Eitel Natalie T. Boelman Troy S. Magney Case M. Prager 《Remote sensing letters.》2017,8(2):175-184
Monitoring of climate-driven expansion of low-stature shrubs in Arctic tundra can be improved through application of high-resolution remote sensing. However, the destructive nature of harvest sampling that is usually performed for validation of these data is resource intensive and can limit future comparisons by destroying benchmark measurements. We compared aboveground shrub biomass estimates derived from terrestrial laser scanning (TLS) and airborne laser scanning (ALS) with the goal of determining whether TLS data can be used to accurately calibrate ALS estimates of shrub biomass in Arctic tundra. We used a leave-one-out cross-validation calibration of canopy volume against harvested shrub biomass to establish predictive relationships between TLS canopy volume and harvested shrub biomass, and between ALS canopy volume and TLS-derived shrub biomass estimates. TLS produced more accurate predictions of shrub biomass (R2 = 0.78; root mean square deviation [RMSD] = 102 g) than did ALS, but the accuracy of ALS-derived shrub biomass predictions was the same whether they were calibrated directly against harvest biomass or against TLS-derived estimates of biomass (R2 = 0.62; RMSD = 140 g). Our results suggest that once the initial TLS-harvest relationship is known, TLS can provide valid ground reference data for calibration of ALS-derived estimates of shrub biomass without the need for additional destructive harvest. 相似文献
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93.
Jennifer A. Sumner Natalie L. Colich Monica Uddin Don Armstrong Katie A. McLaughlin 《Neuropsychopharmacology》2019,85(3):268-278
Background
Recent conceptual models argue that early life adversity (ELA) accelerates development, which may contribute to poor mental and physical health outcomes. Evidence for accelerated development in youths comes from studies of telomere shortening or advanced pubertal development following circumscribed ELA experiences and neuroimaging studies of circuits involved in emotional processing. It is unclear whether all ELA is associated with accelerated development across global metrics of biological aging or whether this pattern emerges following specific adversity types.Methods
In 247 children and adolescents 8 to 16 years of age with wide variability in ELA exposure, we evaluated the hypothesis that early environments characterized by threat, but not deprivation, would be associated with accelerated development across two global biological aging metrics: DNA methylation (DNAm) age and pubertal stage relative to chronological age. We also examined whether accelerated development explained associations of ELA with depressive symptoms and externalizing problems.Results
Exposure to threat-related ELA (e.g., violence) was associated with accelerated DNAm age and advanced pubertal stage, but exposure to deprivation (e.g., neglect, food insecurity) was not. In models including both ELA types, threat-related ELA was uniquely associated with accelerated DNAm age (β = .18) and advanced pubertal stage (β = .28), whereas deprivation was uniquely associated with delayed pubertal stage (β = ?.21). Older DNAm age was related to greater depressive symptoms, and a significant indirect effect of threat exposure on depressive symptoms was observed through DNAm age.Conclusions
Early threat-related experiences are particularly associated with accelerated biological aging in youths, which may be a mechanism linking ELA with depressive symptoms. 相似文献94.
Validation of a semi‐automatic co‐registration of MRI scans in patients with brain tumors during treatment follow‐up
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Anouk van der Hoorn Jiun‐Lin Yan Timothy J. Larkin Natalie R. Boonzaier Tomasz Matys Stephen J. Price 《NMR in biomedicine》2016,29(7):882-889
There is an expanding research interest in high‐grade gliomas because of their significant population burden and poor survival despite the extensive standard multimodal treatment. One of the obstacles is the lack of individualized monitoring of tumor characteristics and treatment response before, during and after treatment. We have developed a two‐stage semi‐automatic method to co‐register MRI scans at different time points before and after surgical and adjuvant treatment of high‐grade gliomas. This two‐stage co‐registration includes a linear co‐registration of the semi‐automatically derived mask of the preoperative contrast‐enhancing area or postoperative resection cavity, brain contour and ventricles between different time points. The resulting transformation matrix was then applied in a non‐linear manner to co‐register conventional contrast‐enhanced T1‐weighted images. Targeted registration errors were calculated and compared with linear and non‐linear co‐registered images. Targeted registration errors were smaller for the semi‐automatic non‐linear co‐registration compared with both the non‐linear and linear co‐registered images. This was further visualized using a three‐dimensional structural similarity method. The semi‐automatic non‐linear co‐registration allowed for optimal correction of the variable brain shift at different time points as evaluated by the minimal targeted registration error. This proposed method allows for the accurate evaluation of the treatment response, essential for the growing research area of brain tumor imaging and treatment response evaluation in large sets of patients. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
95.
ObjectiveTo determine differences in restaurant environments between neighborhood and restaurant type to understand better a food desert's eating environments.MethodsThe Nutrition Environment Measures Survey for restaurants was used to assess restaurant healthfulness. Kruskal-Wallis compared healthy index scores, and Pearson chi-square compared individual items.ResultsHealthy index scores were consistently low across neighborhoods (total mean = 4.6 out of 23). Fast-food restaurants (mean = 5.7) were more healthful than sit-down restaurants (mean = 3.1). Individual comparisons showed more healthy eating facilitators (eg, nutrition information at point-of-purchase, P = 0.004) in food deserts and more available healthful items (eg, whole grain bread, P < 0.001) in the neighborhoods with high incomes.Conclusions and ImplicationsFindings indicate equities in restaurant environments across all neighborhoods but inequities across restaurant types, thus conclude the importance of restaurant type in understanding restaurant healthfulness. Policymakers can use these findings to develop healthy eating strategies in varying neighborhoods. 相似文献
96.
Kohel Kara Hatton-Bowers Holly Williams Natalie Dev Dipti Behrends Donnia Hulse Emily Rida Zainab Dingman Holly Dinkel Danae Gebhart Liz 《Maternal and child health journal》2021,25(4):510-520
Maternal and Child Health Journal - Breastfeeding and responsive feeding are important practices that support the health of infants and women. In the United States, breastfeeding continuation rates... 相似文献
97.
Carl M. Gay C. Allison Stewart Elizabeth M. Park Lixia Diao Sarah M. Groves Simon Heeke Barzin Y. Nabet Junya Fujimoto Luisa M. Solis Wei Lu Yuanxin Xi Robert J. Cardnell Qi Wang Giulia Fabbri Kasey R. Cargill Natalie I. Vokes Kavya Ramkumar Bingnan Zhang Lauren Averett Byers 《Cancer cell》2021,39(3):346-360.e7
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98.
Natalie A Celeste Kathryn M Emmer Willie A Bidot Marcel I Perret-Gentil Raphael A Malbrue 《Journal of the American Association for Laboratory Animal Science》2021,60(2):195
General anesthesia induces many systemic effects, including thermoregulatory impairment and subsequent perioperative hypothermia. Due to the animals’ small size, monitoring and maintaining body temperatures in laboratory rodents during anesthesia is important for successful surgical outcomes and prompt anesthetic recovery. Draping materials have the potential to aid in thermal support during surgical anesthesia. In this study, rectal and surface (infrared) temperatures were measured in C57BL/6 mice under isoflurane anesthesia every 5 min for the duration of a 35-min sham surgery. In addition to placement on a circulating water bath, mice (n = 6/group) were draped with commercial cling film (CF; Press''n Seal, Glad, Oakland, CA), a conventional paper drape (PD), or no drape (ND) during surgery. Results demonstrated that CF-draped animals had significantly higher rectal temperatures than nondraped animals. Furthermore, surface temperatures of CF-draped mice were considerably higher than those of both paper-draped and undraped animals. The data indicate that cling film is an effective material to help minimize hypothermia in mice and potentially in other laboratory rodents requiring general anesthesia.Surgery and anesthesia introduce many challenges, especially in veterinary medicine, due to the diversity of species. One major challenge during general anesthesia involves changes in an animal''s thermoregulatory ability.1,14 Body temperatures in mice and rats fall significantly during anesthesia if no thermal support is provided.29,30 Hypothermia occurs due to drug-induced alterations to the thermoregulatory center, inadequate circulation, and a loss of body heat to the environment from evaporation, radiation, conduction, and convection.7 Mice are particularly susceptible to hypothermia, due to their large surface area per gram of body weight, which permits significant physiologic changes in response to fluctuations in the ambient temperature.31 Covering the animal''s body with towels, drapes, or blankets to reduce the area exposed to the environment can minimize heat loss.6,7,13 Placing the animal on an insulated surface can limit conductive heat loss. In larger animals, warmed fluids can be given perioperatively, heated anesthetic gasses can be administered, and heated blankets and heat packs can be applied to body surfaces to provide exogenous heat.1,7 Safer and more practical methods for rodents are circulating water heating blankets, thermal gel packs, and warming lamps, which are commonly used for thermal support during anesthesia.5,14 Addressing all of these factors can contribute to maintaining normothermia during anesthesia.Risk of mortality is elevated during anesthesia and in the postoperative period, including in rodents.1,13 Hypothermia induced by anesthesia can negatively affect rodents by altering vital parameters such as heart rate and blood pressure and delaying anesthetic recovery.3,5,12,19 These risks require careful selection of an appropriate anesthetic protocol and careful monitoring of the patient throughout anesthesia until full recovery occurs. Strict anesthetic monitoring and the use of supplemental heat devices have been shown to reduce the likelihood of complications, improve overall postoperative recovery, and reduce mortality associated with surgical procedures.1,7,15,16 However, due to these species’ small size, monitoring equipment must be specialized and is often costly. Cost-effective and practical alternative equipment and materials would facilitate monitoring and care of rodents.Various draping options are available for rodent surgery, and their use is vital for both sterile technique and heat retention. Traditionally, paper draping material has been a popular option, because it is relatively inexpensive and can be autoclaved together with surgical instruments.15,16 Some institutions have adopted varying methods and types of draping, including no drape and paper draping. Commercial cling film (CF) has been used as draping due to its low cost, ease of use, and sterility straight out of the box.9 Our study team sought to evaluate the effects of draping material on intraoperative thermoregulation in mice by measuring rectal temperature (modified rectal probe) and surface temperature (infrared device) during a 35-min laparotomy procedure, with both temperature devices chosen for affordability and availability. We hypothesized that mice draped with CF would maintain a higher intraoperative body temperature under general anesthesia than would mice with traditional paper drapes or no drape. 相似文献
99.
100.
Jonathan S. Comer Natalie Hong Bridget Poznanski Karina Silva Maria Wilson 《Journal of clinical child and adolescent psychology》2019,48(1):1-15
The controlled evaluation of treatments for early childhood anxiety and related problems has been a relatively recent area of investigation, and accordingly, trials examining early childhood anxiety treatment have not been well represented in existing systematic reviews of youth anxiety treatments. This Evidence Base Update provides the first systematic review of evidence supporting interventions specifically for the treatment of early childhood anxiety and related problems. Thirty articles testing 38 treatments in samples with mean age < 7.9 years (N = 2,228 children) met inclusion criteria. We applied Southam-Gerow and Prinstein’s (2014) review criteria, which classifies families of treatments according to one of five levels of empirical support—Well-Established, Probably Efficacious, Possibly Efficacious, Experimental, and of Questionable Efficacy. We found family-based cognitive-behavioral therapy (CBT) to be a Well-Established treatment, and Group Parent CBT and Group Parent CBT + Group Child CBT to both be Probably Efficacious treatments. In contrast, play therapy and attachment-based therapy are still only Experimental treatments for early childhood anxiety, relaxation training has Questionable Efficacy, and there is no evidence to date to speak to the efficacy of individual child CBT and/or medication in younger anxious children. All 3 currently supported interventions for early childhood anxiety entail exposure-based CBT with significant parental involvement. This conclusion meaningfully differs from conclusions for treating anxiety in older childhood that highlight the well-established efficacy of individual child CBT and/or medication and that question whether parental involvement in treatment enhances outcomes. 相似文献