891 resultados para displacement force
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Introduction: The posterior inclination of the tibial component is an important factor that can affect the success of total knee arthroplasty. It can reduce the posterior impingement and thus increase the range of flexion, but it may also induce instability in flexion, anterior impingement between the polyethylene of postero-stabilizing knee prosthesis, and anterior conflict with the cortical bone and the stem. Although the problem is identified, there is still a debate on the ideal inclination angle and the surgical technique to avoid an excessive posterior inclination. The aim of this study was to predict the effect of a posterior inclination of the tibial component on the contact pattern on the tibial insert, using a numerical musculoskeletal model of the knee joint. Methods: A 3D finite element model of the knee joint was developed to simulate an active and loaded squat movement after total knee arthroplasty. Flexion was actively controlled by the quadriceps muscle and muscle activations were estimated from EMG data and were synchronized by a feedback algorithm. Two inclinations of the tibial tray were considered: a posterior inclination of 0° or 10°. During the entire range of flexion, the following quantities were calculated: the tibiofemoral and patello-femoral contact force, and the contact pattern on polyethylene insert. The antero-posterior displacement of the contact pattern was also measured. Abaqus 6.7 was used for all analyses. Results: The tibio-femoral and patello-femoral contact forces increased during flexion and reached respectively 4 and 7 BW (bodyweight) at 90° of flexion. They were slightly affected by the inclination of the tibial tray. Without posterior inclination, the contact pattern on the tibial insert remained centered. The contact pressure was lower than 5 MPa below 60° of flexion, but exceeded 20 MPa at 90° of flexion. The posterior inclination displaced the contact point posteriorly by 2 to 4 mm. Conclusion: The inclination of the tibial tray displaced the contactpattern towards the posterior border of the tibial insert. However, even for 10° of inclination, the contact center remained far from the posterior border (12 mm). There was no instability predicted for this movement.
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This study aimed to examine the effects of a 5-h hilly run on ankle plantar (PF) and dorsal flexor (DF) force and fatigability. It was hypothesised that DF fatigue/fatigability would be greater than PF fatigue/fatigability. Eight male trail long distance runners (42.5 ± 5.9 years) were tested for ankle PF and DF maximal voluntary isokinetic contraction strength and fatigue resistance tests (percent decrement score), maximal voluntary and electrically evoked isometric contraction strength before and after the run. Maximal EMG root mean square (RMS(max)) and mean power frequency (MPF) values of the tibialis anterior (TA), gastrocnemius lateralis (GL) and soleus (SOL) EMG activity were calculated. The peak torque of the potentiated high- and low-frequency doublets and the ratio of paired stimulation peak torques at 10 Hz over 100 Hz (Db10:100) were analysed for PF. Maximal voluntary isometric contraction strength of PF decreased from pre- to post-run (-17.0 ± 6.2%; P < 0.05), but no significant decrease was evident for DF (-7.9 ± 6.2%). Maximal voluntary isokinetic contraction strength and fatigue resistance remained unchanged for both PF and DF. RMS(max) SOL during maximal voluntary isometric contraction and RMS(max) TA during maximal voluntary isokinetic contraction were decreased (P < 0.05) after the run. For MPF, a significant decrease for TA (P < 0.05) was found and the ratio Db10:100 decreased for PF (-6.5 ± 6.0%; P < 0.05). In conclusion, significant isometric strength loss was only detected for PF after a 5-h hilly run and was partly due to low-frequency fatigue. This study contradicted the hypothesis that neuromuscular alterations due to prolonged hilly running are predominant for DF.
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Report on a special investigation of the Muscatine County Drug Task Force for the period January 1, 2004 through November 30, 2009
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subsequent extension-induced exhumation. Geochronological dating of various Structural, thermobarometric, and geochronological data place limits on the age and tectonic displacement along the Zanskar shear zone, a major north-dipping synorogenic extensional structure separating the high-grade metamorphic sequence of the High Himalayan Crystalline Sequence from the overlying low-grade sedimentary rocks of the Tethyan Himalaya, A complete Barrovian metamorphic succession, from kyanite to biotite zone mineral assemblages, occurs within the I-km-thick Zanskar shear zone. Thermobarometric data indicate a difference In equilibration depths of 12 +/- 3 km between the lower kyanite zone and the garnet zone, which is Interpreted as a minimum estimate for the finite vertical displacement accommodated by the Zanskar shear zone. For the present-day dip of the structure (20 degrees), a simple geometrical model shows that a net slip of 35 +/- 9 km is required to regroup these samples to the same structural level. Because the kyanite to garnet zone rocks represent only part of the Zanskar shear zone, and because its original dip may have been less than the present-day dip, these estimates fur the finite displacement represent minimum values. Field relations and petrographic data suggest that migmatization and associated leucogranite intrusion in the footwall of the Zanskar shear zone occurred as a continuous profess starting at the Barrovian metamorphic peak and lasting throughout the subsequent extension-induced exhumation. Geochronological dataing of various leucogranitic plutons and dikes in the Zanskar shear zone footwall indicates that the main ductile shearing along the structure ended by 19.8 Ma and that extension most likely initiated shortly before 22.2 Ma.
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Hepatitis A virus (HAV), the prototype of genus Hepatovirus, has several unique biological characteristics that distinguish it from other members of the Picornaviridae family. Among these, the need for an intact eIF4G factor for the initiation of translation results in an inability to shut down host protein synthesis by a mechanism similar to that of other picornaviruses. Consequently, HAV must inefficiently compete for the cellular translational machinery and this may explain its poor growth in cell culture. In this context of virus/cell competition, HAV has strategically adopted a naturally highly deoptimized codon usage with respect to that of its cellular host. With the aim to optimize its codon usage the virus was adapted to propagate in cells with impaired protein synthesis, in order to make tRNA pools more available for the virus. A significant loss of fitness was the immediate response to the adaptation process that was, however, later on recovered and more associated to a re-deoptimization rather than to an optimization of the codon usage specifically in the capsid coding region. These results exclude translation selection and instead suggest fine-tuning translation kinetics selection as the underlying mechanism of the codon usage bias in this specific genome region. Additionally, the results provide clear evidence of the Red Queen dynamics of evolution since the virus has very much evolved to re-adapt its codon usage to the environmental cellular changing conditions in order to recover the original fitness.
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In the 2010 legislative session, the General Assembly passed and the Governor signed into law Senate File 2389 (SF 2389), which provided guidance for Smart Planning in Iowa and established the Iowa Smart Planning Task Force. This Task Force was charged with recommending policies and strategies for creating a stronger planning culture in Iowa, producing more resilient and sustainable communities. The Task Force, along with its two committees and four workgroups, met throughout the summer and fall of 2010 to identify and review best practices, consult local and national experts, and craft recommendations in the best interest of Iowans. A public input process was also implemented, resulting in improved recommendations.
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During the 2010 session, the Iowa Legislature created per House File 2422 a Business Disaster Case Management Task Force. The purpose of the Task Force is to research disaster recovery case management assistance needed for businesses following a major disaster and to recommend steps for providing such assistance following disasters. The Task Force was duly constituted. Its recommendations are contained in this report.
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A unified report from the nine disaster recovery task forces outlining the way to a long-term recovery for Iowa surpassing just a return to normal.
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The Rebuild Iowa Agriculture and Environment Task Force respectfully submits its report to the Rebuild Iowa Advisory Commission (RIAC) for consideration of the impacts of the tornadoes, storms, high winds, and flooding affecting Iowa’s agriculture sector and environment. The Task Force was required to address very complex and multi-faceted issues. Understanding that there were a broad range of immediate concerns, as well as critical issues that need to be addressed in the future, the Task Force structured its work in two sessions. To better address the issues and priorities of the Task Force, this report categorizes the issues as agriculture, conservation, environment, and livestock.
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The Rebuild Iowa Cultural Heritage and Records Retention Task Force respectfully submits its report to the Rebuild Iowa Advisory Commission (RIAC) for its consideration of the impacts of the tornadoes, storms, and flooding on Iowans and their cultural, historical, and arts institutions and organizations and records collections and archives. As the RIAC fulfills its obligations to guide the recovery and reconstruction of Iowa, the cknowledgement that culture and records as Iowa’s identity is important, and that if these items of cultural heritage vanish from Iowa’s landscape, the items that Iowans associate with their history, traditions, and sense of place also disappears. Iowa is certainly not the only state that has experienced this type of disaster; however, many states have not recognized culture and records as critical concerns as part of the recovery and rebuilding process. When rebuilding Iowa stronger, smarter, and safer, quality of life is an important consideration for attracting new residents, making it a necessity to keep culture alive and thriving in Iowa. Additionally, the cultural arts constitute a vital economic industry, providing employment to thousands of Iowa’s citizens and generating millions of dollars in local and government revenue across the state. In the case of records, these items are irreplaceable and provide important information for the daily workings of government and life in our state, and maintain vital records of Iowa’s heritage and traditions. This report provides background information on the damages incurred in Iowa from the disasters and additional context for policy and rebuilding discussions. It also offers recommendations to the RIAC for steps that might be taken to address the significant and important challenges faced by Iowa’s cultural, historical, and arts institutions and organizations; individual artists and other cultural workers; and records retention entities and officials. Supplement to main report.
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The 2008 disasters devastated businesses, farms, homes, schools, non-profit institutions, entire communities, and people’s lives across the state of Iowa. The Rebuild Iowa Advisory Commission (RIAC) is charged by the Governor to guide the state’s recovery and reconstruction process. The Economic and Workforce Development Task Force is respectfully submitting this report to be included and considered in the deliberations of the RIAC. While economic and workforce development are two issues that are inextricably linked and critical to Iowa’s rebuilding strategies, each also requires extraordinary attention in determining what needs to be considered in the very immediate and longer-term recovery. Supplement Information to the August 2008 Economic and Workforce Development Task Force Report
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The Rebuild Iowa Infrastructure and Transportation Task Force is acutely aware of the critical role infrastructure plays in Iowa’s communities, the lives of the residents, and the economic well-being of the state. With encouragement to the Rebuild Iowa Advisory Commission (RIAC) for its consideration of great need for infrastructure and transportation repairs, the Task Force provides its assessment and recommendations. As the RIAC fulfills its obligations to guide the recovery and reconstruction in Iowa, infrastructure and transportation must be recognized for its impact on all Iowans. The tornadoes, storms, and floods were devastating to infrastructure and transportation systems across the state. The damage did not distinguish between privately-owned and public assets. The significance of the damage emerges further with the magnitude of the damage estimates. Infrastructure includes components that some might initially overlook, such as communication systems, landfills, and water treatment. The miles of damaged roads and bridges are more evident to many Iowans. Given the reliance on infrastructure systems, many repairs are already underway, though gaps have emerged in the funding for repairs to certain infrastructure systems. Supplement Information to the August 2008
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Eighty-five of 99 Iowa counties were declared Presidential Disaster Areas for Public Assistance and/orIndividual Assistance as a result of the tornadoes, storms, and floods over the incident period May 25 through August 13, 2008. Response dominated the state’s attention for weeks, with a transition to recovery as the local situations warranted. The widespread damage and severity of the impact on Iowans and their communities required a statewide effort to continue moving forward despite being surrounded by adversity. By all accounts, it will require years for the state to recover from these disasters. With an eye toward the future, recovery is underway across Iowa. As part of the Rebuild Iowa efforts, the Long Term Recovery Planning Task Force was charged with responsibilities somewhat different from other topical Task Force assignments. Rather than assess damage and report on how the state might address immediate needs, the Long Term Recovery Planning Task Force is directed to discuss and discern the best approach to the lengthy recovery process. Certainly, the Governor and Lieutenant Governor expect the task to be difficult; when planning around so many critical issues and overwhelming needs, it is challenging to think to the future, rather than to rise to the current day’s needs.