Post-stroke patients often experience less control and coordination of one of their legs, which could result in a condition known as foot drop. Foot drop is characterized by an inability to properly dorsiflex at the ankle and could lead to problems with foot clearance during gait and ultimately result in the person falling. It is assumed that the Allard Medical ToeOFF® ankle foot orthosis (AFO) is associated with shorter rehabilitation times and better rehabilitation outcomes than the standard fixed plastic AFO, but quantitative data is missing to prove this. We compared people who were prescribed the Allard Medical ToeOFF® AFO (n = 7) with the standard fixed plastic AFO (n = 3) for several different measures. The resulting data was analyzed for trends and the presence of statistically significant differences with the Wilcoxon Rank Sum test. Our statistical significance analysis was inconclusive, but we did identify a trend between the use of the Allard Medical ToeOFF® with greater increases of fractional change in the number of dorsiflexions before fatigue than with the use of the standard fixed plastic AFO. Also, the use of the standard fixed plastic AFO was associated with greater increases in fractional change of gait speed over the 6 week testing period than the use of the Allard Medical ToeOFF®. Further study with larger sample sizes is warranted and is expected to lead to more conclusive results about the presence of significant differences between the subjects using an Allard Medical ToeOFF® AFO and those using a standard fixed plastic AFO. These results could enable physicians in the future to make a more informed decision about which type of brace to prescribe for their patients. / 1 / Emily Sarah Relle

Background:People who have survived a stroke often have post-stroke complications. One common complication is muscle weakness in the lower extremities. To treat this, patients can use an ankle-foot orthosis (AFO). The purpose of this study was to investigate muscle morphology in the quadriceps when walking with an AFO. Method:This feasibility cross over study was made on 7 healthy adults. To measure the morphology, an SMG device was used. The device measured muscle area change, EMG -and MMG activation, knee angle and plantar forces. Statistical analyzes was made for all measured data except knee angle.  Result:The area of the quadriceps was significantly smaller when walking with the AFO in mid-swing phase than without (p=0,035). A significant reduction in force could also be found under the MTP1 (p=0,016) and under the calcaneus (p=0,042) in toe off (60%). The result did not show any significant differences in initial contact (p=0,617), mid stance (p=0,287), toe off (p=0,527) or terminal swing (p=0,712) for muscle area change of quadriceps, or plantar force at MTP5 in toe off (p=0,704). Conclusion:The results suggest that the subjects needed to work more with the quadriceps muscles when walking with the AFO. More studies are needed to reach clinical relevance. / Bakgrund:Personer som har genomgått en stroke lider ofta av diverse komplikationer. En vanlig komplikation är muskelsvaghet i den nedre extremiteten. Ett vanligt hjälpmedel för personer med dessa problem är en ankel-fot-ortos (AFO). Denna studies syfte var att undersöka muskelmorfologi (areaförändringar) i quadriceps muskeln när man går med en AFO jämfört med att gå utan.  Metod:Denna förstudie är en korsstudie som utfördes på 7 friska unga vuxna. Ett SMG-system användes på quadriceps för att mäta muskelarean. Enheten mätte muskelarea förändringar, EMG –och MMG aktivering, knävinkel samt plantara krafter. Statistiska analyser genomfördes på all insamlade data förutom knävinkeln.  Resultat:Arean för quadriceps var signifikant mindre när deltagarna gick med AFO i mid swing jämfört med utan (p=0,035). En signifikant skillnad visade sig i den plantara kraften under MTP1 (p=0,016) och under hälen (p=0,042) i toe off (60%).  Resultatet visade inga signifikanta skillnader i initial contact (p=0,617), mid stance (p=0,287), toe off (p=0,527) eller i terminal swing (p=0,712) för quadriceps, eller plantara krafter på MTP5 under toe off (p=0,704). Slutsats:Resultaten pekar på att deltagarna behöver använda sin quadriceps mer i mid swing när de går med en AFO. Fler studier på området behöver göras för att uppnå klinisk relevans.

No description available.

Ammonia emissions from animal feeding operations (AFOs) have recently come under increased scrutiny. The US Environmental Protection Agency (EPA) has come under increased pressure from special interest groups to regulate ammonia. Regulation of ammonia is very difficult because every facility has different manure management practices. Different management practices lead to different emissions for every facility. Researchers have been tasked by industry to find best management practices to reduce emissions. The task cannot be completed without equipment that can efficiently and accurately compare emissions. To complete this task, a measurement system was developed and performance tested to measure ammonia. Performance tests included uncertainty analysis, system response, and adsorption kinetics. A measurement system was designed for measurement of gaseous emissions from ground level area sources (GLAS) in order to sample multiple receptors with a single sensor. This multiplexer may be used in both local and remote measurement systems to increase the sampling rate of gaseous emissions. The increased data collection capacity with the multiplexer allows for nearly three times as many samples to be taken in the same amount of time while using the same protocol for sampling. System response analysis was performed on an ammonia analyzer, a hydrogen sulfide analyzer, and tubing used with flux chamber measurement. System responses were measured and evaluated using transfer functions. The system responses for the analyzers were found to be first order with delay in auto mode. The tubing response was found to be a first order response with delay. Uncertainty analysis was performed on an ammonia sampling and analyzing system. The system included an analyzer, mass flow controllers, calibration gases, and analog outputs. The standard uncertainty was found to be 443 ppb when measuring a 16 ppm ammonia stream with a 20 ppm span. A laboratory study dealing with the adsorption kinetics of ammonia on a flux chamber was performed to determine if adsorption onto the chamber walls was significant. The study found that the adsorption would not significantly change the concentration of the output flow 30 minutes after a clean chamber was exposed to ammonia concentrations for concentrations above 2.5 ppm.

Individuals with various lower-limb neuromuscular and musculoskeletal impairments are often prescribed passive-dynamic ankle-foot orthoses (PD-AFOs) to compensate for impaired ankle muscle weakness. Several studies have demonstrated the beneficial effects of PD-AFOs on pathological gait, but few studies have examined the influence of the AFO stiffness characteristics on gait performance. One challenge to performing such studies is the difficulty of manufacturing custom AFOs with a wide range of controlled stiffness levels. However, selective laser sintering (SLS) is a well-suited additive manufacturing technique for generating subject-specific PD-AFOs of varied stiffness. Therefore, the overall goal of this study was to use SLS manufactured PD-AFOs to identify the relationships between AFO stiffness and gait performance in patients with various lower-limb neuromuscular and musculoskeletal impairments. Six subjects with unilateral impairments were enrolled in this study. For each subject, one subject-specific PD-AFO equivalent to the subject’s clinically prescribed carbon fiber PD-AFO (nominal), one 20% more compliant and one 20% more stiff were manufactured using SLS. Three-dimensional kinematic and kinetic data were collected from each subject while ambulating with each PD-AFO at two different speeds to allow a comprehensive biomechanical analysis to assess the influence of PD-AFO stiffness on gait performance. The results showed that in the compliant AFO condition, the AFO limb vertical ground reaction force (GRF) impulse during loading and the non-AFO limb medial GRF impulse during push-off decreased. In addition, the AFO limb braking GRF impulse during loading and the non-AFO limb braking GRF impulse in early single-limb stance decreased. Furthermore, in the compliant AFO condition, negative knee work during early single-limb stance increased while positive hip work in early swing decreased in the AFO limb. Overall, as AFO stiffness decreased, the AFO limb contributed less to body support and braking. In addition, a decreased medial GRF impulse coupled with an increased vertical GRF impulse during non-AFO single-limb stance suggests that walking stability may be compromised as AFO stiffness decreases. Thus, a tradeoff may exist between preserving stability and increasing net propulsion, which should be considered when assessing the mobility needs of individuals prescribed PD-AFOs as a result of various neuromuscular and musculoskeletal impairments. / text

No description available.

Rocker profiles are one of the most commonly prescribed footwear modifications provided to individuals with impaired rollover. Impaired rollover is caused due to loss of neuromuscular function (i.e. stoke) or orthotic ankle constraint. When rollover is impaired, continued forward progression is interrupted and walking gait becomes less efficient (i.e. increased energy expenditure). Rocker profile footwear modifications are designed to mimic the functions of the anatomical ankle-foot rockers and provide its users with a smooth and efficient rollover. However, while there is theory governing the design of a rocker profile and subjective descriptions of rocker profile function, the extent to which a rocker profile footwear provides rollover has not yet been quantified. The aim of this study was to quantify effective and ineffective rollover and test whether our rocker profile provides effective rollover. We hypothesized that healthy subjects (n=4) walking with orthotic ankle constraint and the rocker profile (STOP) would have no change in rollover and energy expenditure outputs compared to walking with orthotic ankle free and rocker profile (FREE); but that healthy subjects (n=4) walking in STOP would have a change in rollover and energy expenditure outputs compared to walking with orthotic ankle constraint and no rocker profile (STOP-NR). To test this hypothesis, rollover was quantified as stance phase duration, cadence and radius of curvature and energy expenditure was quantified as heart rate and rating of perceived exertion. In addition to these outputs, we analyzed the ground reaction forces and duration of stance in early, middle and late stance period to determine the effects of the rocker profile footwear components. Through the rollover and energy expenditure outputs of the STOP, FREE and STOP-NR conditions, we quantified effective rollover as 0.29 (0.01) radius of curvature with a heart rate of 110.5(6.7) bpm and ineffective rollover as 0.69(0.12) radius of curvature with a heart rate of 131.5 (8.1) bpm. By creating this scale, we were able to determine that our rocker profile provided effective rollover (0.34[0.04] radius of curvature with a heart rate of 111.3[8.3] bpm). However, a future study with a greater sample size is needed to confirm these results.

Somatic embryogenesis (SE) represents potentially very suitable way of plant production - micropropagation - of plants in vitro. The process had been studied for more than thirty years and a lot of knowledge has been gained in the field though new ways based on new knowledge leading to improvement and increase of the effectiveness of cultivation protocols are still under focus in the field. Relatively recent discovery of aromatic cytokinins lead to new knowledge on very positive effects on different morphogenetic and physiological processes during both cultivation in vitro or in vivo treatments. This gave origin to the topic of the present thesis, which focused on study of the effect of meta-topolin (mT), aromatic cytokinin, on proliferation phase of SE on structural level of embryogenic lines of Norway spruce Picea abies (L.) Karst. The aim of the thesis is analysis of structural development of embryogenic lines with the use of anatomical preparations and quantitative stereological methods. The material represented three embryogenic lines: 107 and 34C were obtained from the Forestry and Game Management Research Institute from the lab of Dr. Jana Malá and the line AFO 541, which was used as a standard line. To compare the effect of mT with benzylaminopurine (BAP) on proportion of different...

Children with cerebral palsy (CP) have a higher than normal O2 uptake (VO2) during walking. While various interventions are used to improve locomotion, little is known about their effect on the metabolic and cardiopulmonary cost of walking. We therefore assessed the effects of one popular intervention, hinged ankle foot orthoses (AFO), on cardiopulmonary and metabolic variables during 2 min of steady state treadmill walking at three speeds: 3 kph, comfortable walking speed (CWS) and fast walking speed (FWS). We also assessed the effect of these braces on comfortable and maximum ground walking speed and on gross motor abilities using the Gross Motor Function Measure. Ten children with spastic diplegic CP (9.01 years ± 2.10) who habitually used hinged AFO participated. Not all children could walk at all speeds on the treadmill however, and some cardiopulmonary and metabolic data on three children were missing due to equipment failure. We performed an ANOVA on data for children who walked at 3 kph and CWS (n=8 for heart rate (HR); n=9 for pulmonary ventilation and metabolic variables) and a t-test on data at FWS (n=9 for HR, n=8 for pulmonary ventilation and metabolic variables). When children wore AFO, absolute VO2 was reduced by 4.6% at 3 kph and by 4.1% at FWS, and absolute VO2 per metre walked by 4.6% and 4.4% at the same speeds, respectively. Adjusting VO2 for body mass, or for resting VO2 or calculating energy expenditure in kJ, revealed the same pattern. Pulmonary ventilation was lower with AFO on by 7.17%, but only at 3 kph. AFO did not affect gross motor abilities. Nor did it affect HR, or the respiratory exchange ratio at any speed, nor any physiologic variable at CWS. We suggest the lower O2 cost may reflect an increase in stability and a corresponding decrease in coactivation of lower limb antagonistic muscles. / Thesis / Master of Science (MSc)