Search results for " Density"
showing 10 items of 2709 documents
Calculations of high-power production target and beamdump for the GSI future Super-FRS for a fast extraction scheme at the FAIR Facility
2005
A superconducting fragment separator (Super-FRS) is being designed for the production and separation of radioactive isotopes at the future FAIR (Facility for Antiprotons and Ion Research) facility at Darmstadt. This paper discusses various aspects and requirements for the high-power production target that will be used in the Super-FRS experiments. The production target must survive over an extended period of time as it will be used during the course of many experiments. The specific power deposited by the high intensity beam that will be generated at the future FAIR facility will be high enough to destroy the target in most of the cases as a result of a single shot from the new heavy ion sy…
Binding of a fluorescent dansylcadaverine-substance P analogue to negatively charged phospholipid membranes.
2000
Abstract We have investigated the binding of a new dansylcadaverine derivative of substance P (DNC-SP) with negatively charged small unilamellar vesicles composed of a mixture of phosphatidylcholine (PC) and either phosphatidylglycerol (PG) or phosphatidylserine (PS) using fluorescence spectroscopic techniques. The changes in fluorescence properties were used to obtain association isotherms at variable membrane negative charges and at different ionic strengths. The experimental association isotherms were analyzed using two binding approaches: (i) the Langmuir adsorption isotherm and the partition equilibrium model, that neglect the activity coefficients; and (ii) the partition equilibrium m…
Tissue characterization of benign brain tumors: Use of NMR-tissue parameters
1988
Abstract To evaluate the potentials of NMR tissue parameters for tissue characterization we investigated 68 patients with benign brain tumors. Tissue parameters were accurately measured by a recently developed interlaced triple sequence. Each individual tumor was characterized by a set of three numbers (relaxation times T 1 and T 2 and proton density Rho). Different tumors exhibited significant overlaps of the three tissue parameters. Therefore a reliable prediction of the histological diagnosis based on the quantitative analysis of tissue parameters alone was not possible. T 2 -prolongation correlated well with water content and “regressive changes” in meningiomas and neuromas.
Association of developmental coordination disorder and low motor competence with impaired bone health: A systematic review.
2021
Aims Individuals with developmental coordination disorder (DCD) and low motor competence (LMC) may be at increased risk of low bone health due to their lifetime physical activity patterns. Impaired bone health increases an individual’s risk of osteoporosis and fracture; therefore, it is necessary to determine whether a bone health detriment is present in this group. Accordingly, this systematic review explores the association between DCD/LMC and bone health. Methods and Procedures Studies were included with assessment of bone health in a DCD/LMC population. Study bias was assessed using the JBI critical appraisal checklist. Due to heterogeneity, meta-analysis was not possible and narrative …
The influence of food competition and host specificity on the transmission of Triaenophorus crassus (Cestoda) and Cystidicola farionis (Nematoda) to …
2000
Abstract As a superior competitor for planktonic food, vendace ( Coregonus albula ), when abundant, is expected to displace whitefish ( Coregonus lavaretus ) from feeding on plankton and to force it to rely more on benthic food. The predicted result would be a reduced abundance of the copepod-transmitted cestode Triaenophorus crassus in whitefish, but an increase in the abundance of the nematode Cystidicola farionis transmitted via benthic amphipods. We studied the occurrence of both parasites in whitefish during 1991–1996 in three interconnected areas at Lake Saimaa, Finland, where the densities of the vendace stocks varied due to natural fluctuation in year-class strengths. In accordance …
One year of training with FES has impressive beneficial effects in a 36-year-old woman with spinal cord injury
2015
International audience; CONTEXT:Reductions of muscular and cardiorespiratory functions are often observed in people with spinal cord injury (SCI) and several studies demonstrated the benefits of aerobic and strengthening exercise training for this population. Functional Electrical Stimulation (FES) of paralyzed muscles has been proposed as a strategy to assist patients in executing functional movement but its utilization during long durations has never been investigated. The purpose of the present study was to assess the effects of a one-year training program with FES (strengthening and rowing) in one subject with SCI. Evoked torque, quadriceps muscle thickness, aerobic exercise capacity an…
In vivo vibrational wave propagation in human tibiae at different ages
1989
Vibrational wave propagation was tested in vivo on the tibial bone of both legs of 56 female volunteers. The impact was produced by a hammer with a force strain gauge and the response was monitored by two accelerometers. The peak amplitude of the accelerations, the velocity of the acceleration wave propagation and damping were analysed for comparison among the different age groups. The results showed significant negative correlations between age and the peak amplitude of acceleration, and the velocity of acceleration wave propagation (p less than 0.01). The damping time of the acceleration wave also had a negative correlation with age. These findings suggested that age differences were rela…
The effects of calorie restriction, intermittent fasting and vegetarian diets on bone health.
2019
Uncountable health care organizations, clinicians, and individuals are striving to prevent obesity and the many chronic medical conditions linked to it by advocating a healthy lifestyle that includes measures such as reducing dietary calorie intake (i.e., calorie restriction = CR and intermittent fasting = IF) or limiting/abolishing animal source foods (i.e., practices termed vegetarianism and veganism). Although these regimens are traditionally considered healthy, their real impact on bone health has yet to be established, and some studies have reported that they have negative effects on bone outcomes. The current work provides an overview of the studies carried out to examine the effect/s…
25-hydroxy vitamin D levels in healthy premenopausal women: Association with bone turnover markers and bone mineral density
2008
Abstract Background Vitamin D deficiency is very common in elderly people while there are very few reports on its incidence, determinants and metabolic consequences in young subjects. Results In 608 young healthy premenopausal women participating in the BONTURNO study, levels of 25-hydroxyvitamin D [25(OH)D] below 20 ng/ml were found in almost a third of the women. Its levels were inversely ( P 2 ) and directly with sunlight exposure during the summer time, and latitude: i.e. the higher the latitude over Italy, the higher the 25(OH)D level. In women on contraceptive pill the mean 25(OH)D level was significantly increased even when the data were adjusted for age, BMI and sun exposure. 25(OH)…
Exercise loading and cortical bone distribution at the tibial shaft
2011
Cortical bone is not a uniform tissue, and its apparent density [cortical volumetric density (vBMD)] varies around the bone cross-section as well as along the axial length of the bone. It is not yet known, whether the varying vBMD distribution is attributable to modulation in the predominant loads affecting bone. The aim of the present study was to compare the cortical bone mass distribution through the bone cortex (radial distribution) and around the center of mass (polar distribution) among 221 premenopausal women aged 17-40 years representing athletes involved in high impact, odd impact, high magnitude, repetitive low impact, repetitive non-impact sports and leisure time physical activit…