23 research outputs found
Comparison of Single Leg Squat Variations on Lower Limb Muscle Activation and Center of Pressure Alterations
International Journal of Exercise Science 12(1): 950-959, 2019. Following anterior cruciate ligament reconstruction, individuals experience inadequate functioning of the quadriceps and decreased muscular strength. Decreased function delays return to physical activity and increases potential for re-injury. While several squat variations exist, a new variation has emerged in rehabilitation. The purpose of this study was to compare muscle activation of the Vastus Lateralis (VL), Vastus Medialis (VM), Rectus Femoris (RF), Gluteus Maximus (GM), and anterior posterior center of pressure (AP displacement) alterations during a single leg squat variation (SLS variation) versus a traditional split squat using electromyography (EMG) in healthy active females. Seventeen females performed one set of both squat variations on a force plate while muscle activation was measured. Paired t-tests were used to compare dependent variable (DV) means between squat variations. Results indicated SLS variation yielded lower peak and mean quadriceps activation compared to traditional split squat, (p \u3c 0.05). However, peak and mean GM muscle activity was greater in the SLS variation compared to the traditional split squat, (p \u3c 0.01). Lastly, AP displacement was greater during the SLS variation, (p \u3c 0.001). All three quadricep muscles had greater peak and mean EMG suggesting the traditional split squat be used for quadricep activation in rehabilitation/training settings, while the SLS variation should be prescribed for greater GM muscle activation. Understanding muscle activation patterns amongst squat variations can be practically applied by therapists, coaches and trainers to aid in reducing risks of arthrokinetic dysfunction via synergistic dominance, faster return to physical activity and normal functions of daily activity
Withdrawal symptoms in children after long-term administration of sedatives and/or analgesics: A literature review. "Assessment remains troublesome"
Background: Prolonged administration of benzodiazepines and/or opioids to children in a pediatric intensive care unit (PICU) may induce physiological dependence and withdrawal symptoms. Objective: We reviewed the literature for relevant contributions on the nature of these withdrawal symptoms and on availability of valid scoring systems to assess the extent of symptoms. Methods: The databases PubMed, CINAHL, and Psychinfo (1980-June 2006) were searched using relevant key terms. Results: Symptoms of benzodiazepine and opioid withdrawal can be classified in two groups: central nervous system effects and autonomic dysfunction. However, symptoms of the two types show a large overlap for benzodiazepine and opioid withdrawal. Symptoms of gastrointestinal dysfunction in the PICU population have been described for opioid withdrawal only. Six assessment tools for withdrawal symptoms are used in children. Four of these have been validated for neonates only. Two instruments are available to specifically determine withdrawal symptoms in the PICU: the Sedation Withdrawal Score (SWS) and the Opioid Benzodiazepine Withdrawal Scale (OBWS). The OBWS is the only available assessment tool with prospective validation; however, the sensitivity is low. Conclusions: Withdrawal symptoms for benzodiazepines and opioids largely overlap. A sufficiently sensitive instrument for assessing withdrawal symptoms in PICU patients needs to be developed
Dissolved organic carbon transformations and microbial community response to variations in recharge waters in a shallow carbonate aquifer
© 2016, The Author(s). In carbonate aquifers, dissolved organic carbon from the surface drives heterotrophic metabolism, generating CO2 in the subsurface. Although this has been a proposed mechanism for enhanced dissolution at the water table, respiration rates and their controlling factors have not been widely evaluated. This study investigates the composition and concentration of dissolved organic carbon (DOC) reaching the water table from different recharge pathways on a subtropical carbonate island using a combination of DOC concentration measurements, fluorescence and absorption characterisation. In addition, direct measurements of the microbial response to the differing water types were made. Interactions of rainfall with the vegetation, via throughfall and stemflow, increase the concentration of DOC. The highest DOC concentrations are associated with stemflow, overland recharge and dissolution hole waters which interact with bark lignin and exhibit strong terrestrial-derived characteristics. The groundwater samples exhibit the lowest concentrations of DOC and are comprised of refractory humic-like organic matter. The heterotrophic response seems to be controlled by the concentration of DOC in the sample. The terrestrially sourced humic-like matter in the stemflow and dissolution hole samples was highly labile, thus increasing the amount of biologically produced CO2 to drive dissolution. Based on the calculated respiration rates, microbial activity could enhance carbonate dissolution, increasing porosity generation by a maximum of 1%kyrâ1 at the top of the freshwater lens
A detailed study of land surface microwave emissivity over the Indian subcontinent
Microwave emissivities of land surfaces on global basis have been derived using Special Sensor Microwave/Imager brightness temperature data. These derived emissivities are compared with other reported emissivity values to demonstrate the accuracy of the retrievals. Following these results, detailed analyses on the microwave emissivities of the Indian subcontinent are carried out using the monthly mean emissivity estimate for two years. The Indian subcontinent has a wide variety of geographic and biospheric classes with distinctly different emissivity characteristics. The spectral and monthly variations of microwave emissivity for different tropical land surface classes are examined. This study is significant for microwave radiance assimilation in weather forecast models and also for the utilization of the data from passive microwave sensors onboard the Indo-French satellite âMegha-Tropiques,â which is dedicated to tropical atmospheric studies
Simultaneous GDNF and BDNF application leads to increased motoneuron survival and improved functional outcome in an experimental model for obstetric brachial plexus lesions
Motoneurons of the neonate rat respond to proximal axonal injury with morphologic and functional changes and ultimately with neuronal death. Recent studies showed that both glial cell-line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF) reduce induced degeneration of motoneurons after axotomy and avulsion. Whether rescued motoneurons are functionally intact has been argued. In the present investigation, the authors have used a proximal crush lesion of the brachial plexus in neonatal rats as the experimental model of neuronal injury. This allowed the authors to study the effects of trophic factor administration on injured motoneurons and the relationship between motoneuron survival and extremity function. Trophic factors were locally released by small polymer implants in a low-dose slow-release mode. Six groups of 10 animals were prepared: BDNF, GDNF, GDNF/BDNF, control, sham, and normals. The number of surviving motoneurons was determined by retrograde tracer techniques using Fluorogold and Fastblue. Extremity function was quantitatively evaluated with functional muscle testing at day 56. The results of this study demonstrate that trophic factors applied separately had no effect, whereas combined trophic factor application (GDNF/BDNF group) had a dramatic rescue effect on motoneuron survival as compared with the control groups, which also effected significantly greater strength. The authors conclude that a combination of trophic factors leads to enhanced motoneuron survival, with improved voluntary function as the animal enters adulthood so that exogenous trophic support of motoneurons might have a role in the treatment of all types of severe neonatal plexopathies, maintaining the viability of motoneurons until reconstructive surgery provides them with a pathway for regeneration and endogenous trophic support
Categorising and Comparing Cluster-Based DPA Distinguishers
Side-channel distinguishers play an important role in differential power analysis, where real world leakage information is compared against hypothetical predictions in order to guess at the underlying secret key. A class of distinguishers which can be described as âcluster-basedâ have the advantage that they are able to exploit multi-dimensional leakage samples in scenarios where only loose, âsemi-profiledâ approximations of the true leakage forms are available. This is by contrast with univariate distinguishers exploiting only single points (e.g. correlation), and Template Attacks requiring concise fitted models which can be overly sensitive to mismatch between the profiling and attack acquisitions. This paper collects togetherâto our knowledge, for the first timeâthe various different proposals for cluster-based DPA (concretely, Differential Cluster Analysis, First Principal Components Analysis, and Linear Discriminant Analysis), and shows how they fit within the robust âsemi-profilingâ attack procedure proposed by Whitnall et al. at CHES 2015. We provide discussion of the theoretical similarities and differences of the separately proposed distinguishers as well as an empirical comparison of their performance in a range of (real and simulated) leakage scenarios and with varying parameters. Our findings have application for practitioners constrained to rely on âsemi-profiledâ models who wish to make informed choices about the best known procedures to exploit such information.</p
Molecular and Spectroscopic Characterization of Water Extractable Organic Matter from Thermally Altered Soils Reveal Insight into Disinfection Byproduct Precursors
To characterize the effects of thermal-alteration
on water extractable
organic matter (WEOM), soil samples were heated in a laboratory at
225, 350, and 500 °C. Next, heated and unheated soils were leached,
filtered, and analyzed for dissolved organic carbon (DOC) concentration,
optical properties, molecular size distribution, molecular composition,
and disinfection byproduct (DBP) formation following the addition
of chlorine. The soils heated to 225 °C leached the greatest
DOC and had the highest C- and N-DBP precursor reactivity per unit
carbon compared to the unheated material or soils heated to 350 or
500 °C. The molecular weight of the soluble compounds decreased
with increasing heating temperature. Compared to the unheated soil
leachates, all DBP yields were higher for the leachates of soils heated
to 225 °C. However, only haloacetonitrile yields (Όg/mg<sub>C</sub>) were higher for leachates of the soils heated to 350 °C,
whereas trihalomethane, haloacetic acid and chloropicrin yields were
lower compared to unheated soil leachates. Soluble N-containing compounds
comprised a high number of molecular formulas for leachates of heated
soils, which may explain the higher yield of haloacetonitriles for
heated soil leachates. Overall, heating soils altered the quantity,
quality, and reactivity of the WEOM pool. These results may be useful
for inferring how thermal alteration of soil by wildfire can affect
water quality