Treatment for patients in end-stage heart failure has been revolutionized by the development of the ventricular assist device (VAD), an implantable heart pump used for long-term mechanical ...circulatory support. These devices are now small, lightweight, and efficient continuous-flow pumps that have replaced the larger, heavier, fill-to-empty predecessors. Management of the VAD case requires interdisciplinary effort across a diverse continuum of care and an understanding of new implantation techniques. This article describes current advances in VAD technology, indications for use, and perioperative nursing considerations related to patients who have undergone VAD implantation.
A therapeutic recommendation for restoring function in individuals with chronic low back pain (CLBP) is manual therapy through manipulative spinal or muscle energy techniques.
To compare the ...effectiveness of two osteopathic manipulative techniques on clinical low back symptoms and trunk neuromuscular postural control in male workers with CLBP.
Ten male workers with CLBP were randomly allocated to two groups: high-velocity low-amplitude (HVLA) manipulation or muscle energy techniques (MET). Each group received one therapy per week for both techniques during 7 weeks of treatment. Pain and function were measured by using the Numeric Pain-Rating Scale, the McGill Pain Questionnaire and the Roland Morris Disability Questionnaire. The lumbar flexibility was assessed by Modified Schober Test. Electromyography (EMG) and force platform measurements were used for evaluation of trunk muscular activation and postural balance, respectively at three different times: baseline, post intervention, and 15 days later.
Both techniques were effective (
< 0.01) in reducing pain with large clinical differences (-1.8 to -2.8) across immediate and after 15 days. However, no significant effect between groups and times was found for other variables, namely neuromuscular activation and postural balance measures.
Both techniques (HVLA thrust manipulation and MET) were effective in reducing back pain immediately and 15 days later. Neither technique changed the trunk neuromuscular activation patterns nor postural balance in male workers with LBP.
These results may facilitate clinical decision-making for CLBP management in physiotherapy programs.
•Postural control declines with age.•Low back pain can affect balance performance during a one-legged stance.•Trunk muscle activation changes with age and the presence of low back pain.•Patients with ...chronic low back pain present decreased back muscle activation.
Postural control declines with age and can be affected by low back pain. Poor balance has been reported in people with chronic low back pain (CLBP), which in turn could be explained by the changes in trunk muscle activation.
Are there differences between younger and older adults with and without chronic low back pain (CLBP) on trunk muscle activity during one-legged stance task?
Twenty (20) with, and 20 subjects without nonspecific CLBP participated in the study. Each group was comprised of 10 younger (50% males; mean age: 31 years) and 10 older adults (50% males; mean age: 71 years). Subjects performed 3 × 30-second trials of one-legged stance, with eyes open, on a force platform, while surface electromyography (EMG) measurements were obtained bilaterally on the multifidus at L5, iliocostalis lumborum at L3, rectus abdominis and biceps femoris muscles.EMG amplitude analysis was processed by the Root Mean Square (250 ms window epochs) and normalized by the peak of activation during the balance tasks, to determine the muscular activity of each muscle.
Participants with CLBP presented 15% lower lumbar muscle activation (p < 0.05), and 23% higher co-activation (ratio between rectus adominis by multifidus) than participants without CLBP, regardless of age. Significant differences (p < 0.05) between older and young groups were observed only for lower lumbar muscles (mean 24% lower in older than younger adults) and rectus adominis muscles (mean 17% lower in older than younger adults).
CLBP individuals have different trunk muscle activity than those without CLBP, and older adults exhibit lower trunk activation during one-legged stance balance task. The use of the EMG in evaluation of trunk neuromuscular function during one-legged stance may thus be a valuable tool when assessing balance in CLBP and older people.
Taking the lead from complexity theory and complex systems methodology, the article argues that we are engaged in a contradictory process when encountering, analysing and dealing with complexity. We ...face opposite tendencies that indicate an in-built dynamic between the increase of complexity and its reduction. The increase partly comes through evolution, defined as the transmission of information and partly from the desire for a human-built world that functions more efficiently. The reduction of complexity is due partly to the necessity of minimizing unwanted and unintended consequences of its increase, and partly due to the continued re-alignment between social systems and their environments. The article examines the public debate about human stem cell research, the debates in the 18th century about the free circulation of commodities and opinions, and the attempts to provide answers to the question debated between Einstein and Freud: why war? The article concludes by arguing that the plea for a re-alignment of scientific disciplines will not suffice. Instead, the study of the co-evolution between science and society offers itself as a strategic research site by focusing on the dynamic interplay between the increase of complexity and its reduction.
Nanocapillaries through insulating foils (PET or “Mylar”) have received interest as a target for beams of slow highly-charged ions. Transmission of projectiles in their initial charge state have been ...measured for angles of incidence larger than the geometrical opening angle. Ions are guided along the capillary axis and do not closely interact with the inner walls of the capillary. We have developed a classical trajectory transport theory of this self-organized guiding process that relates the microscopic charge-up with macroscopic material properties and includes multi-capillary effects on a phenomenological level. Transmission coefficients are investigated, yielding good agreement with experimental data. The dependence of angular spread of transmitted ions on the angle of incidence and incident energy can be correctly described.
Abstract The purpose of this study was to compare back muscle fatigue of younger and older participants with and without chronic low back pain (CLBP). Twenty participants without and 20 with ...nonspecific CLBP participated in this study. Each group contained 10 younger (50% males; mean age: 31 ± 6 yrs) and 10 older adults (50% males; age mean: 71 ± 7 yrs). Two isometric fatigue protocols were presented randomly: (1) to maintain the unsupported trunk at the horizontal position while on a 45° Roman chair for a minute, and (2) to maintain a 10% of body weight box close to the trunk in the upright position for a minute. Surface electromyography (EMG) signals from the back (multifidus and iliocostalis) and one hip (biceps femoris) muscles were recorded bilaterally, and the median frequency fatigue estimate from linear regression slopes of the EMG time-series was computed. There were no significant ( P > 0.05) age effects, and group-by-age interaction in both isometric and functional fatigue tasks. However, the CLBP groups (both younger and old) displayed more back fatigue than people without CLBP in both fatigue protocols ( P < 0.01; effect size varying of d = 0.17–0.32). This study was sensitive to discriminate that individuals with CLBP did present significantly more pronounced EMG back fatigue than people without CLBP, in both younger and older adults. These results have significant clinical implications for low back pain rehabilitation programs with regard to endurance assessment in both younger and older.
Ultrasound microbial cell disrupters operating at around 20 kHz are often physically large and, due to significant heating, can be unsuitable for small sample volumes where biochemical integrity of ...the extracted product is required. Development of a compact device based on a 63.5-mm diameter, 6.5-mm thick tubular transducer for rapid cell disruption in small-volume samples in a high-intensity acoustic cavitation field with minimal temperature rises is described here. Suspensions of
Saccharomyces cerevisiae were exposed to cavitation for various times in the compact device and a 20-kHz probe sonicator. Cell disruption was assessed by protein release and by staining. Yeast cell disruption was greater in the novel 267-kHz sonicator than in the 20-kHz probe sonicator for the same exposure time. A 1-dimensional (1-D) transfer matrix model analysis for piezoelectric resonators was applied to an axial cross-section of the tubular sonicator to predict frequencies of mechanical resonance in the sample volume associated with maximum acoustic pressure. Admittance measurements identified frequencies of electrical resonance. Ultrasonic cavitation noise peaks were detected by a hydrophone at both the mechanical and electrical resonances. Cell breakage efficiency was twice as great in terms of protein released per dissipated watt at the mechanical resonance predicted by the model, compared to those at the electrical resonance frequencies. The results form a basis for rational design of an ultrasound cell disruption technique for small-volume samples.
Simulation of heavy-ion guiding in insulators Lemell, C.; Schiessl, K.; Nowotny, H. ...
Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms,
March 2007, 2007-03-00, Letnik:
256, Številka:
1
Journal Article
Recenzirano
Guiding of charged particles through insulating target structures (capillaries, glass cones, parallel glass plates) has become a topic of considerable interest. It has been shown for insulating ...capillary targets that highly charged ions are deflected along the capillary axis while remaining in their initial charge state. Similar results have been reported for the focusing of ion beams by glass cones. We have developed a classical transport theory relating microscopic charge-up with macroscopic material properties. For insulating capillary transmission good agreement with experiments is found. Currently investigated experimental systems will be accessible to theory within the same framework.
The central circadian pacemaker in the suprachiasmatic nucleus and interaction of clock genes with the hypothalamus pituitary adrenal axis are responsible for very distinct cortisol concentrations. ...Unphysiologically high doses of glucocorticoids that do not follow the circadian rhythm lead to increased rates of morbidity, mortality and reduced quality of life.
Does a switch to modified-release hydrocortisone in multimorbid elderly patients offer benefits compared to a conventional therapy regime?
Evaluation, analysis and discussion of statistics, recent research results and expert advice.
Overdosage and unphysiological timing of cortisol administration result in higher incidences of obesity, hypertension, hyperglycemia, coronary heart disease and cardiac events. Body weight, body mass index and HbA1c decline with Plenadren® (Shire Pharmaceuticals Ireland Limited, Dublin, Ireland) treatment compared to conventional therapy. CD16+ natural killer cells and natural killer cytotoxycity are reduced, and the incidence of respiratory-tract infections is increased, with conventional therapy compared to Plenadren®. Cortisol influences sleep pattern and sleep quality by its circadian secretion.
Novel modified-release hydrocortisone preparations offer diverse benefits with regard to their effect on metabolism, cardiovascular risk, immunity and sleep, which might be beneficial in particular in multimorbid elderly.