636 research outputs found
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Obesity-induced Upper Extremity Lymphedema
Summary: Obesity increases the risk of upper extremity lymphedema following treatment for breast cancer and can cause lower extremity lymphatic dysfunction in extremely obese individuals. We report the first patient with obesity-induced upper extremity lymphedema. A 62-year-old man with a previous body mass index (BMI) of 105.6, presented with a BMI 60.3 following weight loss. He complained of lymphedema of all 4 extremities, which was confirmed by lymphoscintigraphy. Because the upper limbs are more resistant to lymphedema than the lower extremities, a higher BMI threshold may be necessary to cause upper extremity lymphatic dysfunction
Driving under the influence of risky peers : an experimental study of adolescent risk taking.
Both passive and active social influences may affect adolescents' dangerous driving. In this study, we used an experimental paradigm to delineate these two influences with actual peers. Adolescents completed a simulated driving task, and we measured risk preferences of each member of the peer group. We used hierarchical linear modeling to partition variance in risky decisions. Adolescents experienced many more crashes when they had âpassengersâ present who reported a strong preference for risk taking and who actively provided decision-making guidance. Although youth in the passive peer condition were also influenced by the riskiness of their peers, this relation was less strong relative to the active condition. We discuss the need for interventions focussing on active and passive peer influence
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Combined Lymphedema and Capillary Malformation of the Lower Extremity
Background: Primary lymphedema and capillary malformation are independent vascular malformations that can cause overgrowth of the lower extremity. We report a series of patients who had both types of malformations affecting the same leg. The condition is unique but may be confused with other types of vascular malformation overgrowth conditions (eg, KlippelâTrenaunay and Parkes Weber). Methods: Our Vascular Anomalies Center and Lymphedema Program databases were searched for patients with both capillary malformation and lymphedema. Diagnosis of lymphedemaâcapillary malformation was made by history, physical examination, and imaging studies. Because lymphedemaâcapillary malformation has phenotypical overlap with other conditions, only patients who had imaging confirming their diagnosis were included in the analysis. Clinical and radiological features, morbidity, and treatment were recorded. Results: Eight patients (4 females and 4 males) had confirmed lymphedemaâcapillary malformation. Referring diagnosis was KlippelâTrenaunay syndrome (n = 4), diffuse capillary malformation with overgrowth (n = 3), or lymphatic malformation (n = 1). The condition was unilateral (n = 6) or bilateral (n = 2). Morbidity included infection (n = 6), difficulty fitting clothes (n = 6), bleeding or leaking vesicles (n = 5), leg length discrepancy (n = 4), and difficulty ambulating (n = 3). All patients were managed with compression regimens. Operative management was liposuction (n = 3), treatment of phlebectatic veins (n = 3), staged skin/subcutaneous excision (n = 1), and/or epiphysiodesis (n = 1). Conclusions: Lymphedema and capillary malformation can occur together in the same extremity. Both conditions independently cause limb overgrowth primarily because of subcutaneous adipose deposition. Compression garments and suction-assisted lipectomy can improve the condition. Lymphedemaâcapillary malformation should not be confused with other vascular malformation overgrowth diseases that have different morbidities and treatments
Helping education undergraduates to use appropriate criteria for evaluating accounts of motivation
The aim of the study was to compare students in a control group with those in a treatment group with respect to evaluative comments on psychological accounts of motivation. The treatment group systematically scrutinized the nature and interpretation of evidence that supported different accounts, and the assumptions, logic, coherence and clarity of accounts. Content analysis of 74 scripts (using three categories) showed that the control group students made more assertions than either evidential or evaluative points, whereas the treatment group used evaluative statements as often as they used assertion. The findings provide support for privileging activities that develop understanding of how knowledge might be contested, and suggest a need for further research on pedagogies to serve this end. The idea is considered that such understanding has a pivotal role in the development of critical thinking
Representing addition and subtraction : learning the formal conventions
The study was designed to test the effects of a structured intervention in teaching children to represent addition and subtraction. In a post-test only control group design, 90 five-year-olds experienced the intervention entitled Bi-directional Translation whilst 90 control subjects experienced typical teaching. Post-intervention testing showed some significant differences between the two groups both in terms of being able to effect the addition and subtraction operations and in being able to determine which operation was appropriate. The results suggest that, contrary to historical practices, children's exploration of real world situations should precede practice in arithmetical symbol manipulation
A simple radionuclide-driven single-ion source
We describe a source capable of producing single barium ions through nuclear
recoils in radioactive decay. The source is fabricated by electroplating 148Gd
onto a silicon {\alpha}-particle detector and vapor depositing a layer of BaF2
over it. 144Sm recoils from the alpha decay of 148Gd are used to dislodge Ba+
ions from the BaF2 layer and emit them in the surrounding environment. The
simultaneous detection of an {\alpha} particle in the substrate detector allows
for tagging of the nuclear decay and of the Ba+ emission. The source is simple,
durable, and can be manipulated and used in different environments. We discuss
the fabrication process, which can be easily adapted to emit most other
chemical species, and the performance of the source
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Resolution of Primary Lymphedema: A Case Report
Summary: Primary lymphedema is a rare, progressive disease that typically affects the lower extremity. The condition is not curable, and the limb enlarges over time because of subcutaneous fibroadipose deposition. We present a patient with clinical and radiographical evidence of resolution of primary lymphedema. This observation may provide greater insight into the pathophysiology of the disease
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Hanford Radiological Protection Support Services Annual Report for 1999
During calendar year (CY) 1999, the Pacific Northwest National Laboratory (PNNL) performed its customary radiological protection support services in support of the U.S. Department of Energy (DOE) Richland Operations Office (RL) and the Hanford contractors. These services included: (1) external dosimetry, (2) internal dosimetry, (3) in vivo measurements, (4) radiological records, (5) instrument calibration and evaluation, and (6) calibration of radiation sources traceable to the National Institute of Standards and Technology (NIST). The services were provided under a number of programs as summarized here. Along with providing site-wide nuclear accident and environmental dosimetry capabilities, the Hanford External Dosimetry Program (HEDP) supports Hanford radiation protection programs by providing external radiation monitoring capabilities for all Hanford workers and visitors to help ensure their health and safety. Processing volumes decreased in CY 1999 relative to prior years for all types of dosimeters, with an overall decrease of 19%. During 1999, the HEDP passed the National Voluntary Laboratory Accreditation Program (NVLAP) performance testing criteria in 15 different categories. HEDP computers and processors were tested and upgraded to become Year 2000 (Y2K) compliant. Several changes and improvements were made to enhance the interpretation of dosimeter results. The Hanford Internal Dosimetry Program (HIDP) provides for the assessment and documentation of occupational dose from intakes of radionuclides at the Hanford Site. Performance problems carried over from CY 1998 continued to plague the in vitro bioassay contractor. A new contract was awarded for the in vitro bioassay program. A new computer system was put into routine operation by the in vivo bioassay program. Several changes to HIDP protocols were made that were related to bioassay grace periods, using field data to characterize the amount of alpha activity present and using a new default particle size. The number of incidents and high routine investigations that required follow-up were lower compared with 1998. Also, the number of excreta analyses performed decreased compared with CY 1998. The In Vivo Monitoring Program for Hanford (formerly the Hanford Whole Body Counting Project) provides the in vivo counting services for Hanford Site radiation workers. New computer hardware and software were put into routine operation to acquire, analyze, and store the measurement data. The technical procedures were revamped to reflect operational changes implemented with the new computer system. The U.S. Department of Energy Laboratory Accreditation Program (DOELAP) accreditation was extended to include two additional categories. New detectors were purchased for wound counting applications. The 8,085 in vivo measurements performed in 1999 represent a 2% decrease from 1998. Several high-purity germanium detectors were repaired at the In Vivo Radioassay and Research Facility, thereby saving out-of-service time and money compared with returning the detectors to the vendor. There were 11 phantom loans made through the DOE Phantom Library in 1999, including 2 international loans
A magnetically-driven piston pump for ultra-clean applications
A magnetically driven piston pump for xenon gas recirculation is presented.
The pump is designed to satisfy extreme purity and containment requirements, as
is appropriate for the recirculation of isotopically enriched xenon through the
purification system and large liquid xenon TPC of EXO-200. The pump, using
sprung polymer gaskets, is capable of pumping more than 16 standard liters per
minute (SLPM) of xenon gas with 750 torr differential pressure.Comment: 6 pages, 5 figure
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