55 research outputs found
Numerical simulations for performance optimization of a few-cycle terawatt NOPCPA system
We present a systematic numerical design and performance study of an ultra-broadband noncollinear optical parametric chirped pulse amplification (NOPCPA) system. Using a split-step Fourier approach, we model a three-stage amplifier system which is designed for the generation of 7 fs pulses with multi-terawatt peak intensity. The numerical results are compared with recent experimental data. Several important aspects and design parameters specific to NOPCPA are identified, and the values of these parameters required to achieve optimal working conditions are investigated. We identify and analyze wavelength-dependent gain saturation effects, which are specific to NOPCPA and have a strong influence on the parametric amplification process. © Springer-Verlag 2007
Patient free text reporting of symptomatic adverse events in cancer clinical research using the National Cancer Institute's Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE)
Objective: The study sought to describe patient-entered supplemental information on symptomatic adverse events (AEs) in cancer clinical research reported via a National Cancer Institute software system and examine the feasibility of mapping these entries to established terminologies. Materials and Methods: Patients in 3 multicenter trials electronically completed surveys during cancer treatment. Each survey included a prespecified subset of items from the National Cancer Institute's Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE). Upon completion of the survey items, patients could add supplemental symptomatic AE information in a free text box. As patients typed into the box, structured dropdown terms could be selected from the PRO-CTCAE item library or Medical Dictionary for Regulatory Activities (MedDRA), or patients could type unstructured free text for submission. Results: Data were pooled from 1760 participants (48% women; 78% White) who completed 8892 surveys, of which 2387 (26.8%) included supplemental symptomatic AE information. Overall, 1024 (58%) patients entered supplemental information at least once, with an average of 2.3 per patient per study. This encompassed 1474 of 8892 (16.6%) dropdowns and 913 of 8892 (10.3%) unstructured free text entries. One-third of the unstructured free text entries (32%) could be mapped post hoc to a PRO-CTCAE term and 68% to a MedDRA term. Discussion: Participants frequently added supplemental information beyond study-specific survey items. Almost half selected a structured dropdown term, although many opted to submit unstructured free text entries. Most free text entries could be mapped post hoc to PRO-CTCAE or MedDRA terms, suggesting opportunities to enhance the system to perform real-time mapping for AE reporting. Conclusions: Patient reporting of symptomatic AEs using a text box functionality with mapping to existing terminologies is both feasible and informative
Sufficient levels of 25-hydroxyvitamin D and protein intake required to increase muscle mass in sarcopenic older adults - The PROVIDE study
BACKGROUND:
Inadequate nutritional intake and altered response of aging muscles to anabolic stimuli from nutrients contribute to the development of sarcopenia. Nutritional interventions show inconsistent results in sarcopenic older adults, which might be influenced by their basal nutritional status.
OBJECTIVE:
To test if baseline serum 25-hydroxyvitamin D (25(OH)D) concentrations and dietary protein intake influenced changes in muscle mass and function in older adults who received nutritional intervention.
METHODS AND DESIGN:
Post-hoc analysis was performed in the PROVIDE study that was a randomized controlled, double blind trial among 380 sarcopenic older adults. This study showed that those who received a vitamin D and leucine-enriched whey protein medical nutrition drink for 13 weeks gained more appendicular muscle mass (aMM), and improved lower-extremity function as assessed by the chair stand test compared with controls. To define low and high groups, a baseline serum concentration of 50 nmol/L 25(OH)D and baseline dietary protein intake of 1.0 g/kg/d were used as cut offs.
RESULTS:
At baseline, participants with lower 25(OH)D concentrations showed lower muscle mass, strength and function compared with participants with a high 25(OH)D, while the group with lower protein intake (g/kg/day) had more muscle mass at baseline compared with the participants with higher protein intake. Participants with higher baseline 25(OH)D concentrations and dietary protein intake had, independent of other determinants, greater gain in appendicular muscle mass, skeletal muscle index (aMM/h2), and relative appendicular muscle mass (aMM/body weight × 100%) in response to the nutritional intervention. There was no effect modification of baseline 25(OH)D status or protein intake on change in chair-stand test.
CONCLUSIONS:
Sufficient baseline levels of 25(OH)D and protein intake may be required to increase muscle mass as a result of intervention with a vitamin D and protein supplement in sarcopenic older adults. This suggests that current cut-offs in the recommendations for vitamin D and protein intake could be considered the "minimum" for adults with sarcopenia to respond adequately to nutrition strategies aimed at attenuating muscle loss
Software for administering the National Cancer Institute’s patient-reported outcomes version of the common terminology criteria for adverse events: Usability study
Background: The US National Cancer Institute (NCI) developed software to gather symptomatic adverse events directly from patients participating in clinical trials. The software administers surveys to patients using items from the Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) through Web-based or automated telephone interfaces and facilitates the management of survey administration and the resultant data by professionals (clinicians and research associates). Objective: The purpose of this study was to iteratively evaluate and improve the usability of the PRO-CTCAE software. Methods: Heuristic evaluation of the software functionality was followed by semiscripted, think-aloud protocols in two consecutive rounds of usability testing among patients with cancer, clinicians, and research associates at 3 cancer centers. We conducted testing with patients both in clinics and at home (remotely) for both Web-based and telephone interfaces. Furthermore, we refined the software between rounds and retested. Results: Heuristic evaluation identified deviations from the best practices across 10 standardized categories, which informed initial software improvement. Subsequently, we conducted user-based testing among 169 patients and 47 professionals. Software modifications between rounds addressed identified issues, including difficulty using radio buttons, absence of survey progress indicators, and login problems (for patients) as well as scheduling of patient surveys (for professionals). The initial System Usability Scale (SUS) score for the patient Web-based interface was 86 and 82 (P=.22) before and after modifications, respectively, whereas the task completion score was 4.47, which improved to 4.58 (P=.39) after modifications. Following modifications for professional users, the SUS scores improved from 71 to 75 (P=.47), and the mean task performance improved significantly (4.40 vs 4.02; P=.001). Conclusions: Software modifications, informed by rigorous assessment, rendered a usable system, which is currently used in multiple NCI-sponsored multicenter cancer clinical trials
Preparing for Critical Infrastructure Breakdowns: The Limits of Crisis Management and the Need for Resilience
Plasma lipid profiles discriminate bacterial from viral infection in febrile children
Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection ar
Implications of Shock-Facilitated Alteration on Mars from EBSD and EDS Analysis of the Nakhlites
No abstract available
Implications of Shock-Facilitated Alteration on Mars from EBSD and EDS Analysis of the Nakhlites
No abstract available
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