The kinematics and kinetics of riding a racehorse: A quantitative comparison of a training simulator and real horses.

PubMed

Walker, A M; Applegate, C; Pfau, T; Sparkes, E L; Wilson, A M; Witte, T H

2016-10-03

Movement of a racehorse simulator differs to that of a real horse, but the effects of these differences on jockey technique have not been evaluated. We quantified and compared the kinematics and kinetics of jockeys during gallop riding on a simulator and real horses. Inertial measurement units were attached mid-shaft to the long bones of six jockeys and the sacrum of the horse or simulator. Instrumented stirrups were used to measure force. Data were collected during galloping on a synthetic gallop or while riding a racehorse simulator. Jockey kinematics varied more on a real horse compared to the simulator. Greater than double the peak stirrup force was recorded during gallop on real horses compared to the simulator. On the simulator stirrup forces were symmetrical, whereas on a real horse peak forces were higher on the opposite side to the lead limb. Asymmetric forces and lateral movement of the horse and jockey occurs away from the side of the lead leg, likely a result of horse trunk roll. Jockeys maintained a more upright trunk position on a real horse compared to simulator, with no change in pitch. The feet move in phase with the horse and simulator exhibiting similar magnitude displacements in all directions. In contrast the pelvis was in phase with the horse and simulator in the dorso-ventral and medio-lateral axes while a phase shift of 180° was seen in the cranio-caudal direction indicating an inverted pendulum action of the jockey. Copyright © 2016 Elsevier Ltd. All rights reserved.

Prediction of residual shear strength of corroded reinforced concrete beams

NASA Astrophysics Data System (ADS)

Imam, Ashhad; Azad, Abul Kalam

2016-09-01

With the aim of providing experimental data on the shear capacity and behavior of corroded reinforced concrete beams that may help in the development of strength prediction models, the test results of 13 corroded and four un-corroded beams are presented. Corrosion damage was induced by accelerated corrosion induction through impressed current. Test results show that loss of shear strength of beams is mostly attributable to two important damage factors namely, the reduction in stirrups area due to corrosion and the corrosion-induced cracking of concrete cover to stirrups. Based on the test data, a method is proposed to predict the residual shear strength of corroded reinforced concrete beams in which residual shear strength is calculated first by using corrosion-reduced steel area alone, and then it is reduced by a proposed reduction factor, which collectively represents all other applicable corrosion damage factors. The method seems to yield results that are in reasonable agreement with the available test data.

16 CFR 1203.16 - Dynamic strength of retention system test.

Code of Federal Regulations, 2011 CFR

2011-01-01

... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Dynamic strength of retention system test... retention system test. (a) Test equipment. (1) ISO headforms without the lower chin portion shall be used...

16 CFR 1203.16 - Dynamic strength of retention system test.

Code of Federal Regulations, 2010 CFR

2010-01-01

... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Dynamic strength of retention system test... retention system test. (a) Test equipment. (1) ISO headforms without the lower chin portion shall be used...

16 CFR 1203.16 - Dynamic strength of retention system test.

Code of Federal Regulations, 2014 CFR

2014-01-01

... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Dynamic strength of retention system test... retention system test. (a) Test equipment. (1) ISO headforms without the lower chin portion shall be used...

16 CFR 1203.16 - Dynamic strength of retention system test.

Code of Federal Regulations, 2012 CFR

2012-01-01

... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Dynamic strength of retention system test... retention system test. (a) Test equipment. (1) ISO headforms without the lower chin portion shall be used...

16 CFR § 1203.16 - Dynamic strength of retention system test.

Code of Federal Regulations, 2013 CFR

2013-01-01

... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Dynamic strength of retention system test. Â... retention system test. (a) Test equipment. (1) ISO headforms without the lower chin portion shall be used...

End effector with astronaut foot restraint

NASA Technical Reports Server (NTRS)

Monford, Leo G., Jr. (Inventor)

1991-01-01

The combination of a foot restraint platform designed primarily for use by an astronaut being rigidly and permanently attached to an end effector which is suitable for attachment to the manipulator arm of a remote manipulating system is described. The foot restraint platform is attached by a brace to the end effector at a location away from the grappling interface of the end effector. The platform comprises a support plate provided with a pair of stirrups for receiving the toe portion of an astronaut's boots when standing on the platform and a pair of heel retainers in the form of raised members which are fixed to the surface of the platform and located to provide abutment surfaces for abutting engagement with the heels of the astronaut's boots when his toes are in the stirrups. The heel retainers preclude a backward sliding movement of the feet on the platform and instead require a lifting of the heels in order to extract the feet. The brace for attaching the foot restraint platform to the end effector may include a pivot or swivel joint to permit various orientations of the platform with respect to the end effector.

The Effects of the Air Cast Sports Stirrup on Postural Sway in Normal Males

DTIC Science & Technology

1993-01-01

Pittsburgh Pittsburgh, PAI Paula Sammarone, MA, ATC Date Rangos School of Health Sciences I Director, Athletic Training Duquesne University I Pittsburgh, PA I...sprain occurs, tearing of the ligaments also occur, which results in de- afferentization of the articular nerves (20). 1 Several treatment modalities...intermediate ranges. Articular nerve fibers have lower tensile strength than collagen fibers (21). Since most inversion injuries of the ankle result in some

Primary Care and Regular Breast Cancer Screening Among Under-Served Minority Women

DTIC Science & Technology

1999-08-01

PAP SMEAR A pap smear is a test in which you lie on a table with your feet in the stirrups, and the doctor or nurse examines the female internal...exam is when the breast is felt for lumps by a doctor or nurse . 33. Have vou ever had a breast physical exam by a doctor, nurse or medical assistant...IN TO QUESTION #39) 3 DON’T KNOW 4 REF 34. When was vour most recent breast physical exam by a doctor, nurse or medical assistant? NHIS 1 1 year

AORN Ergonomic Tool 6: lifting and carrying supplies and equipment in the perioperative setting.

PubMed

Waters, Thomas; Baptiste, Andrea; Short, Manon; Plante-Mallon, Lori; Nelson, Audrey

2011-08-01

Perioperative team members often are required to lift and carry heavy supplies and equipment into and around the OR; this includes lifting equipment such as hand tables, fluoroscopy boards, stirrups, Wilson frames, irrigation containers for lithotripsy, and heavy instrument pans. Lifting heavy objects creates considerable risk for musculoskeletal injuries to the back and shoulders. AORN Ergonomic Tool 6: Lifting and Carrying Supplies and Equipment in the Perioperative Setting can help caregivers evaluate lifting and carrying tasks and take measures to protect themselves from injury. Caregivers can use the revised National Institute for Occupational Safety and Health lifting equation to assess whether a specific lifting task can be performed safely. Published by Elsevier Inc.

Knee Brace Would Lock And Unlock Automatically

NASA Technical Reports Server (NTRS)

Myers, Neill; Forbes, John; Shadoan, Mike; Baker, Kevin

1995-01-01

Proposed knee brace designed to aid rehabilitation of person who suffered some muscle damage in leg. Not limited to locking in straight-leg position and, instead, locks at any bend angle. Does not prevent knee from bearing weight. Instead, knee brace allows knee to bear weight and locks only when foot and lower leg bear weight. Thus, brace prevents flexion that wearer desired to prevent but could not prevent because of weakened muscles. Knee bends freely to exercise knee-related muscles. Knee brace strapped at upper end to leg above knee, and anchored at lower end by stirrup under foot. Joint mechanism (identical mechanisms used in left and right assemblies) allows knee joint to flex freely except when weight applied to heel.

System and method for moving a probe to follow movements of tissue

NASA Technical Reports Server (NTRS)

Feldstein, C.; Andrews, T. W.; Crawford, D. W.; Cole, M. A. (Inventor)

1981-01-01

An apparatus is described for moving a probe that engages moving living tissue such as a heart or an artery that is penetrated by the probe, which moves the probe in synchronism with the tissue to maintain the probe at a constant location with respect to the tissue. The apparatus includes a servo positioner which moves a servo member to maintain a constant distance from a sensed object while applying very little force to the sensed object, and a follower having a stirrup at one end resting on a surface of the living tissue and another end carrying a sensed object adjacent to the servo member. A probe holder has one end mounted on the servo member and another end which holds the probe.

Moment redistribution in continuous reinforced concrete beams strengthened with carbon-fiber-reinforced polymer laminates

NASA Astrophysics Data System (ADS)

Aiello, M. A.; Valente, L.; Rizzo, A.

2007-09-01

The results of tests on continuous steel-fiber-reinforced concrete (RC) beams, with and without an external strengthening, are presented. The internal flexural steel reinforcement was designed so that to allow steel yielding before the collapse of the beams. To prevent the shear failure, steel stirrups were used. The tests also included two nonstrengthened control beams; the other specimens were strengthened with different configurations of externally bonded carbon-fiber-reinforced polymer (CFRP) laminates. In order to prevent the premature failure from delamination of the CFRP strengthening, a wrapping was also applied. The experimental results obtained show that it is possible to achieve a sufficient degree of moment redistribution if the strengthening configuration is chosen properly, confirming the results provided by two simple numerical models.

Constitutive relationships of prestressed steel fiber concrete membrane elements

NASA Astrophysics Data System (ADS)

Hoffman, Norman S.

Steel Fiber Concrete (SFC) displays certain tensile and shear characteristics which are beneficial for concrete that is loaded in a state of shear stress. For example, prestressed bridge beams carry shear load in their web by utilizing shear stirrups. If the properties of SFC can be better understood, then it may be possible to replace the shear stirrups with SFC. The first step in understanding this behavior is to develop a constitutive model for prestressed SFC. Two groups of full-scale prestressed steel fiber concrete (SFC) panels, with a nominal strength of 6 ksi, were tested in the Universal Element Testing machine at Thomas TC Hsu Structural Testing Laboratory to establish the effect of fiber and the level of prestress on the constitutive laws of fiber concrete and prestressing tendon. The specimens contained from 5 to 20 fully tensioned, low-relaxation grade 270 tendons. Fiber content ranged from 0.5% to 1.5% using high performance hooked end fibers. The first group of five panels, designated Group TEF, was used to determine the basic constitutive properties of prestressed SEC for use in the Softened Membrane Model (SMM). The constitutive model consists of smeared tensile and compressive stress strain relationships. An equation for softening with respect of both fiber content and tensile strain is presented. Also presented is a new equation for prestressed SFC in tension. It is notable that the behavior of prestressed SFC in tension displayed significant post-cracking tensile strength for fiber contents ranging from 0.5% to 1.5% by volume. Prior research on SFC using unreinforced dog-bone specimens, or prismatic specimens reinforced with only a single isolated tendon, are not capable of capturing SFC behavior afforded by the stress state, multiple load paths, and confinement situation available in full-scale panel assemblies. The second set of 5 test panels, designated Group TAF, was used to examine the properties of prestressed SFC under the conditions of pure shear. The constitutive model was incorporated into the softened membrane model framework and an analytic model was developed that was used to accurately predict the behavior of the specimens loaded in pure shear.

Finite Element Analysis of Increasing Column Section and CFRP Reinforcement Method under Different Axial Compression Ratio

NASA Astrophysics Data System (ADS)

Jinghai, Zhou; Tianbei, Kang; Fengchi, Wang; Xindong, Wang

2017-11-01

Eight less stirrups in the core area frame joints are simulated by ABAQUS finite element numerical software. The composite reinforcement method is strengthened with carbon fiber and increasing column section, the axial compression ratio of reinforced specimens is 0.3, 0.45 and 0.6 respectively. The results of the load-displacement curve, ductility and stiffness are analyzed, and it is found that the different axial compression ratio has great influence on the bearing capacity of increasing column section strengthening method, and has little influence on carbon fiber reinforcement method. The different strengthening schemes improve the ultimate bearing capacity and ductility of frame joints in a certain extent, composite reinforcement joints strengthening method to improve the most significant, followed by increasing column section, reinforcement method of carbon fiber reinforced joints to increase the minimum.

Two-dimensional tricycle arsenene with a direct band gap.

PubMed

Ma, ShuangYing; Zhou, Pan; Sun, L Z; Zhang, K W

2016-03-28

Based on a comprehensive investigation including ab initio phonon and finite-temperature molecular dynamics calculations, we find that two-dimensional tricycle-shaped arsenene (T-As) is robust and even stable under high temperature. T-As is energetically comparable to previously reported chair-shaped arsenene (C-As) and more stable than stirrup-shaped arsenene (S-As). In contrast to C-As and S-As, the monolayer T-As is a direct band gap semiconductor with an energy gap of 1.377 eV. Our results indicate that the electronic structure of T-As can be effectively modulated by stacking, strain, and patterning, which shows great potential of T-As in future nano-electronics. Moreover, by absorbing H or F atoms on the surface of T-As along a specific direction, nanoribbons with desired edge type and even width can be obtained, which is suitable for the fabrication of nano-devices.

Wing walls for enhancing the seismic performance of reinforced concrete frame structures

NASA Astrophysics Data System (ADS)

Yang, Weisong; Guo, Xun; Xu, Weixiao; Yuan, Xin

2016-06-01

A building retrofitted with wing walls in the bottom story, which was damaged during the 2008 M8.0 Wenchuan earthquake in China, is introduced and a corresponding 1/4 scale wing wall-frame model was subjected to shake table motions to study the seismic behavior of this retrofitted structural system. The results show that wing walls can effectively protect columns from damage by moving areas that bear reciprocating tension and compression to the sections of the wing walls, thus achieving an extra measure of seismic fortification. A `strong column-weak beam' mechanism was realized, the flexural rigidity of the vertical member was strengthened, and a more uniform distribution of deformation among all the stories was measured. In addition, the joint between the wing walls and the beams suffered severe damage during the tests, due to an area of local stress concentration. A longer area of intensive stirrup is suggested in the end of the beams.

A new species of the genus Discolaimus Cobb, 1913 (Nematoda: Dorylaimida: Qudsianematidae) from Qinghai, China.

PubMed

Wu, Wen-Jia; Yan, Lin; Xu, Chun-Ling; Wang, Ke; Jin, Sheng-Ying; Xie, Hui

2016-03-07

A new species of the family Qudsianematidae Jairajpuri, 1965 collected from soil from Qinghai Province, China is described as Discolaimus anemaqen n. sp. It is mainly characterized by having a disc-like lip region with six labial sectors separated by six Y-shaped radial grooves; amphid fovea an inverted-stirrup shape; odontostyle aperture 53-59% of its length; anterior part of pharynx with two swellings, basal part expanded gradually with a sheath of tissue visible ventrally and at the base; no groups of large cells observed in cardiac region; female genital system amphidelphic; tail dorsally convex, conoid, with flat ventral side and bluntly rounded terminus, and males not found. The new species is close to D. major Thorne, 1939, D. similis Thorne, 1939 and D. silvicolus Sauer & Annells, 1985 in most measurements, but can be differentiated from them by lip morphology, pharynx structure, body size, and tail shape. A key to the species of Discolaimus is also provided.

Health Disparities among LGBT Older Adults and the Role of Nonconscious Bias

PubMed Central

Foglia, Mary Beth; Fredriksen-Goldsen, Karen I.

2015-01-01

CHJ, in her late fifties and in a long-standing same-sex relationship, had scheduled an appointment with an ob-gyn for bleeding likely related to previously diagnosed uterine fibroids. Her prior ob-gyn had recently retired, and all of her patients had been transferred to the care of another doctor. CHJ was somewhat reluctant to be seen by a new ob-gyn but overcame her trepidation because her prior doctor had highly recommended him. She undressed, donned the requisite gown, and positioned herself on the examining table and in the stirrups with the help of a medical assistant. The doctor entered the room and briefly introduced himself. As CHJ was being examined, the physician looked up and asked if she was sexually active. CHJ responded yes and started to feel discomfited, wondering where this line of questioning was going. The physician said, “Change to your fibroid is large. Haven’t you experienced quite a bit of pain during sexual intercourse with your husband?” CHJ tensed and simply replied, “No, I haven’t experienced any pain.” PMID:25231786

Axial Compression Behavior of a New Type of Prefabricated Concrete Sandwich Wall Panel

NASA Astrophysics Data System (ADS)

Qun, Xie; Shuai, Wang; Chun, Liu

2018-03-01

A novel type of prefabricated concrete sandwich wall panel which could be used as a load-bearing structural element in buildings has been presented in this paper. Compared with the traditional sandwich panels, there are several typical characteristics for this wall system, including core columns confined by spiral stirrup along the cross-section of panel with 600mm spacing, precast foamed concrete block between two structural layers as internal insulation part, and a three-dimensional (3D) steel wire skeleton in each layer which is composed of two vertical steel wire meshes connected by horizontally short steel bar. All steel segments in the panel are automatically prefabricated in factory and then are assembled to form steel system in site. In order to investigate the structural behavior of this wall panel, two full-scale panels have been experimentally studied under axial compressive load. The test results show that the wall panel presents good load-bearing capacity and integral stiffness without out-of-plane flexural failure. Compared to the panel with planar steel wire mesh in concrete layer, the panel with 3D steel wire skeleton presents higher strength and better rigidity even in the condition of same steel ratio in panels which verifies that the 3D steel skeleton could greatly enhance the structural behavior of sandwich panel.

Building and design defects observed in the residential sector and the types of damage observed in recent earthquakes in Turkey

NASA Astrophysics Data System (ADS)

Tolga Çöğürcü, M.

2015-01-01

Turkey is situated in a very active earthquake region. In the last century, several earthquakes resulted in thousands of deaths and enormous economic losses. In 1999, the Marmara earthquake had an approximate death toll of more than 20 000, and in 2011, the Van earthquake killed 604 people. In general, Turkish residential buildings have reinforced concrete structural systems. These reinforced concrete structures have several deficiencies, such as low concrete quality, non-seismic steel detailing, and inappropriate structural systems including several architectural irregularities. In this study, the general characteristics of Turkish building stock and the deficiencies observed in structural systems are explained, and illustrative figures are given with reference to Turkish Earthquake Code 2007 (TEC, 2007). The poor concrete quality, lack of lateral or transverse reinforcement in beam-column joints and column confinement zones, high stirrup spacings, under-reinforced columns and over-reinforced beams are the primary causes of failures. Other deficiencies include weak column-stronger beam formations, insufficient seismic joint separations, soft story or weak story irregularities and short columns. Similar construction and design mistakes are also observed in other countries situated on active earthquake belts. Existing buildings still have these undesirable characteristics, so to prepare for future earthquakes, they must be rehabilitated.

Construction and design defects in the residential buildings and observed earthquake damage types in Turkey

NASA Astrophysics Data System (ADS)

Cogurcu, M. T.

2015-04-01

Turkey is situated in a very active earthquake region. In the last century, several earthquakes resulted in thousands of deaths and enormous economic losses. In 1999, the Kocaeli earthquake had an approximate death toll of more than 20 000, and in 2011 the Van earthquake killed 604 people. In general, Turkish residential buildings have reinforced concrete structural systems. These reinforced concrete structures have several deficiencies, such as low concrete quality, non-seismic steel detailing and inappropriate structural systems including several architectural irregularities. In this study, the general characteristics of Turkish building stock and the deficiencies observed in structural systems are explained, and illustrative figures are given with reference to the Turkish Earthquake Code 2007. The poor concrete quality, lack of lateral or transverse reinforcement in beam-column joints and column confinement zones, high stirrup spacings, under-reinforced columns and over-reinforced beams are the primary causes of failures. Other deficiencies include weak-column-stronger-beam formations, insufficient seismic joint separations, soft-story or weak-story irregularities and short columns. Similar construction and design mistakes are also observed in other countries situated on active earthquake belts. Existing buildings still have these undesirable characteristics, and so to prepare for future earthquakes they must be rehabilitated.

[Concomitant injuries after upper ankle joint dislocations].

PubMed

Dann, K; Wahler, G; Neubauer, N; Steiner, R; Titze, W; Wagner, M

1996-09-01

Functional treatment with the Air Stirrup Ankle Brace recommended by C. N. Stover in 1979 can reduce pathological inversion of the ankle joint. In our retrospective study of 109 patients treated by this kind of ankle brace we found 96 patients (88%) with excellent results. Only 13 patients (12%) reported moderate to good results. To detect and characterize their painful conditions of ankles we did a clinical, radiological and MRI-Investigation. In only 2 cases we found a moderate instability after clinical investigation, anterior stress roentgenogram and talar tilt. By using the MRI-investigation 1.0 Tesla with a 512 x 360 Matrix we could find 10 cases with osteochondral lesions of the ankle. In 7 cases there was separated ossicle in the fibulotalar joint, in 1 case we detected a fracture of the processus anterior tali, in another case we could see a posttraumatic lesion of the talus and calcaneus with bone bruise and at least one osteochondral fracture of the distal tibia. The capability of the MRI to detect particularly osteo-chondral lesions of the talus and the tibiofibular joint was shown in 10 of 13 cases. Therefore we recommend to do an MRI-investigation on all patients after ankle sprain if there are painful conditions within the ankle after conservative treatment.

Confinement Effect on Material Properties of RC Beams Under Flexure

NASA Astrophysics Data System (ADS)

Kulkarni, Sumant; Shiyekar, Mukund Ramchandra; Shiyekar, Sandip Mukund

2017-12-01

In structural analysis, especially in indeterminate structures, it becomes essential to know the material and geometrical properties of members. The codal provisions recommend elastic properties of concrete and steel and these are fairly accurate enough. The stress-strain curve for concrete cylinder or a cube specimen is plotted. The slope of this curve is modulus of elasticity of plain concrete. Another method of determining modulus of elasticity of concrete is by flexural test of a beam specimen. The modulus of elasticity most commonly used for concrete is secant modulus. The modulus of elasticity of steel is obtained by performing a tension test of steel bar. While performing analysis by any software for high rise building, cross area of plain concrete is taken into consideration whereas effects of reinforcement bars and concrete confined by stirrups are neglected. Present aim of study is to determine elastic properties of reinforced cement concrete beam. Two important stiffness properties such as AE and EI play important role in analysis of high rise RCC building idealized as plane frame. The experimental program consists of testing of beams (model size 150 × 150 × 700 mm) with percentage of reinforcement varying from 0.54 to 1.63% which commensurate with existing Codal provisions of IS:456-2000 for flexural member. The effect of confinement is considered in this study. The experimental results are verified by using 3D finite element techniques.

Comparison of custom-moulded ankle orthosis with hinged joints and off-the-shelf ankle braces in preventing ankle sprain in lateral cutting movements.

PubMed

Lee, Winson C C; Kobayashi, Toshiki; Choy, Barton T S; Leung, Aaron K L

2012-06-01

A custom moulded ankle orthosis with hinged joints potentially offers a better control over the subtalar joint and the ankle joint during lateral cutting movements, due to total contact design and increase in material strength. To test the above hypothesis by comparing it to three other available orthoses. Repeated measures. Eight subjects with a history of ankle sprains (Grade 2), and 11 subjects without such history performed lateral cutting movements in four test conditions: 1) non-orthotic, 2) custom-moulded ankle orthosis with hinges, 3) Sport-Stirrup, and 4) elastic ankle sleeve with plastic support. A VICON motion analysis system was used to study the motions at the ankle and subtalar joints. The custom-moulded ankle orthosis significantly lowered the inversion angle at initial contact (p = 0.006) and the peak inversion angle (p = 0.000) during lateral cutting movements in comparison to non-orthotic condition, while the other two orthoses did not. The three orthoses did not affect the plantarflexion motions, which had been suggested by previous studies to be important in shock wave attenuation. The custom-moulded ankle orthosis with hinges could better control inversion and thus expected to better prevent ankle sprain in lateral cutting movements. Custom-moulded ankle orthoses are not commonly used in preventing ankle sprains. This study raises the awareness of the use of custom-moulded ankle orthoses which are expected to better prevent ankle sprains.

Effects of Ankle Braces Upon Agility Course Performance in High School Athletes

PubMed Central

Beriau, Mark R.; Cox, William B.; Manning, James

1994-01-01

The purpose of this study was to compare the effects of wearing the AircastTM Sports Stirrup, AircastTM Training brace, Swede-OTM brace, and DonJoyTM Ankle Ligament Protector while running an agility course. Eighty-five high school athletes with no history of ankle injury and no experience in wearing any ankle support served as subjects. Each subject participated in four separate testing sessions. During sessions 1 and 4, subjects ran the agility course under the control (unbraced) conditions. Sessions 2 and 3 consisted of randomly wearing the ankle braces while running the agility course. A questionnaire concerning support, comfort, and restriction was completed by each subject after wearing each of the braces. An analysis of variance (ANOVA) with repeated measures revealed that a significant difference existed between the agility times. Tukey's post hoc test indicated that a significant difference existed between each ankle brace and the control 2 agility times as well as a control 1 and control 2 time difference. The control time difference was attributed to a learning effect. An ANOVA with repeated measures of only the four braces revealed that a significant difference existed between the agility times. Tukey's post hoc test showed the only difference was between the DonJoy Ankle Ligament Protector and the Aircast Training brace. We concluded: 1) there is limited practical performance effect upon agility while wearing an ankle brace; and 2) an athlete's perceived comfort, support, and performance restriction are contributing factors that may directly influence the effectiveness of ankle bracing. PMID:16558284

Understanding risks of workplace injury in labor and delivery.

PubMed

Stichler, Jaynelle F; Feiler, Judd L; Chase, Kimberlie

2012-01-01

To understand nurse and other staff perceptions about care activities in labor and delivery (L&D) that were performed with high frequency, required high exertion, and had the greatest potential to cause injury and to determine what personal characteristics might be related to the caregiving tasks with potential for injury. This exploratory study employed a mixed methods design using qualitative open-ended questions and quantitative surveys administered in three different times (n = 56, 58, and 58). A 22-room L&D unit in a women's hospital with 8,500 annual deliveries. Nurses and assistive staff. High-risk tasks were classified in three categories. High-exertion tasks included (a) moving patients in labor, delivery, recovery (LDR) beds to other locations; (b) breaking delivery beds and applying stirrups; (c) assisting dependent patients with mobility in bed; and (d) pushing medical equipment and delivery carts. Awkward posture tasks during patient care included (a) listening for heart tones; (b) performing difficult vaginal exams; (c) keeping the fetal head off of the cord during cord prolapse; and (d) assisting with epidurals. Culture of safety tasks included (a) physician requests to conduct patient care tasks that put staff at risk for injury; (b) providers ignoring broken equipment in the environment; (c) responding to emergent/urgent situations without regard to self-posturing to prevent injury; and (d) holding patients' legs during delivery at the physician's direction. Several significant correlations were noted between demographic variables and high potential for risk items. This study provides the first information about the caregiving tasks L&D nurses perceive to be risky for personal injury because of their high frequency and exertion or breaches in the culture of safety. © 2011 AWHONN, the Association of Women's Health, Obsteric and Neonatal Nurses.

Wing 1 of protein HOP2 is as important as helix 3 in DNA binding by MD simulation.

PubMed

Moktan, Hem; Zhou, Donghua H

2018-05-01

The repair of programmed DNA double-strand breaks through recombination is required for proper association and disjunction of the meiotic homologous chromosomes. Meiosis-specific protein HOP2 plays essential roles in recombination by promoting recombinase activities. The N-terminal domain of HOP2 interacts with DNA through helix 3 (H3) and wing 1 (W1). Mutations in wing 1 (Y65A/K67A/Q68A) slightly weakened the binding but mutations in helices 2 and 3 (Q30A/K44A/K49A) nearly abolished the binding. To better understand such differential effects at atomic level, molecular dynamics simulations were employed. Despite losing some hydrogen bonds, the W1-mutant DNA complex was rescued by stronger hydrophobic interactions. For the wild type and W1-mutant, the protein was found to slide along the DNA grooves as the DNA rolls along its double-helix axis. This motion could be functionally important to facilitate the precise positioning of the single-stranded DNA with the homologous double-stranded DNA. The sliding motion was reduced in the W1-mutant. The H-mutant nearly lost all intermolecular interactions. Moreover, an additional mutation in wing 1 (Y65A/K67A/Q68A/K69A) also caused complete complex dissociation. Therefore, both wing 1 and helix 3 make important contribution to the DNA binding, which could be important to the strand invasion function of HOP2 homodimer and HOP2-MND1 heterodimer. Similar to cocking a medieval crossbow with the archer's foot placed in the stirrup, wing 1 may push the minor groove to cause distortion while helix 3 grabs the major groove.

Vegetation of Southwestern watersheds in the nineteenth century

USGS Publications Warehouse

Leopold, Luna Bergere

1951-01-01

The recollections of many old-timers who tell of grass “stirrup high” have given rise to the idea that vegetation in the Southwest was uniformly better in the middle of the last century than it is at present. The change is usually attributed to overgrazing, which timed if it did not cause extensive gullying of the alluvial valleys,I lowering the water table and decreasing the availability of water for plant use. This idea of an originally verdant vegetation, deteriorated as a result of man’s activities, has led to overoptimism concerning the possible results of reduced grazing. Obviously, any decrease in grazing pressure is a step in the right direction, but it is no exaggeration to say that recovery fo vegetation density on depleted ranges, even after protection for years, has been spotty and, in many places, disappointing. We may have allowed ourselves to be deluded by hopes of ‘restoring’ over large areas a level of vegetation density that was originally attained only in selected localities.This conclusion is supported by the published diaries and field notes of members of early American exploring parties. They show that in certain places, particularly in south-central Arizona where grass is now meager, the alluvial valleys formerly supported large expanses of grassland. However, there were also many areas, even alluvial valleys, where grass was so poor that forage for a string of horses could hardly be obtained. Other areas, such as the Rio Puerco Valley, supported good grass in some places but only scattered shrubs, furnishing poor forage, in others, though until well past the middle of the nineteenth century extensive grazing had been prevented by frequent raids of hostile Indians.

The "All-Inside" Arthroscopic Broström Procedure With Additional Suture Anchor Augmentation: A Prospective Study of 45 Consecutive Patients.

PubMed

Cottom, James M; Baker, Joseph S; Richardson, Phillip E

Lateral ankle sprains are a common injury that typically respond well to nonoperative therapy. When nonoperative therapy fails and patients develop chronic lateral ankle instability, they become candidates for surgical repair. The present study examined 45 consecutive patients (45 ankles) with chronic lateral ankle instability who underwent arthroscopic Broström repair using a double-row suture anchor construct. The 45 patients (27 females and 18 males) were followed up for a mean of 14 (range 12 to 20) months. The mean time to weightbearing with crutches was 3.3 (range 2 to 4) days, and full weightbearing was initiated at a mean of 14.4 (range 12 to 16) days. All patients participated in structured physical therapy, which was started at 21.6 (range 18 to 23) days. Patients were transitioned to regular shoe gear with a stirrup-style ankle brace at 28.7 (range 26 to 31) days. The American Orthopaedic Foot and Ankle Society scale scores improved from an average preoperative score of 48.7 (range 45 to 55) to 95.4 (range 90 to 100) postoperatively. The average visual analog scale decreased from 8 (range 6 to 10) preoperatively to 0.6 (range 0 to 5) postoperatively at the last follow-up visit. The Karlsson-Peterson score postoperatively was 87 of 100. We have shown that patients with this new arthroscopic Broström technique modified with a proximal suture anchor can begin weightbearing earlier than previously reported, without adverse effects in terms of pain, functional outcomes scores, and clinical outcomes. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Rates of interventions in labor and birth across Canada: findings of the Canadian Maternity Experiences Survey.

PubMed

Chalmers, Beverley; Kaczorowski, Janusz; O'Brien, Beverley; Royle, Cathie

2012-09-01

Rates of interventions in labor and birth should be similar across a country if evidence-based practice guidelines are followed. This assumption is tested by comparison of some practices across the 13 provinces and territories of Canada. The objective of this study was to describe the wide provincial and territorial variations in rates of routine interventions and practices during labor and birth as reported by women in the Maternity Experiences Survey of the Canadian Perinatal Surveillance System. A sample of 8,244 eligible women was identified from a randomly selected sample of recently born infants drawn from the May 2006 Canadian Census. The sample was stratified by province and territory. Computer-assisted telephone interviews were conducted with participating birth mothers by Statistics Canada on behalf of the Public Health Agency of Canada. Interviews took an average of 45 minutes and were completed when infants were between 5 and 10 months old (9-14 mo in the territories). Completed responses were obtained from 6,421 women (78%). Provincial and territorial variations in rates of routine intervention used during labor and birth are reported. The percentage range of mothers' experience of induction (range 30.9%), epidural (53.7%), continuous electronic fetal monitoring (37.9%), and medication-free pain management during labor (40.7%) are provided, in addition to the use of episiotomy (14.1%) or "stitches" (48.3%), being in a "flat lying position" (42.2%), and having their legs in stirrups for birth (35.7%). Wide variations in the use of most of the interventions were found, ranging from 14.1 percent to 53.7 percent. Rates of intervention in labor and birth showed considerable variation across Canada, suggesting that usage is not always evidence based but may be influenced by a variety of other factors. © 2012, Copyright the Authors Journal compilation © 2012, Wiley Periodicals, Inc.

Evaluation of Shear Strength of RC Beams with Multiple Interfaces Formed before Initial Setting Using 3D Printing Technology

PubMed Central

Kim, Kyeongjin; Park, Sangmin; Jeong, Yoseok; Lee, Jaeha

2017-01-01

With the recent development of 3D printing technology, concrete materials are sometimes used in 3D printing. Concrete structures based on 3D printing have been characterized to have the form of multiple layer build-up. Unlike general concrete structures, therefore, the 3D-printed concrete can be regarded as an orthotropic material. The material property of the 3D-printed concrete’s interface between layers is expected to be far different from that of general concrete bodies since there are no aggregate interlocks and weak chemical bonding. Such a difference finally affects the structural performance of concrete structures even though the interfaces are formed before initial setting of the concrete. The current study mainly reviewed the changes in fracture energy (toughness) with respect to various environmental conditions of such interface. Changes in fracture energies of interfaces between concrete layers were measured using low-speed Crack Mouth Opening Displacement (CMOD) closed loop concrete fracture test. The experimental results indicated reduction in fracture energy as well as tensile strengths. To improve the tensile strength of interfaces, the use of bridging materials is suggested. Since it was assumed that reduction in fracture energy could be a cause of shear strength, to evaluate the reduced structural performance of concrete structure constructed with multiple interfaces by 3D printing technology, the shear strength of RC beam by 3D printing technology was predicted and compared with that of plain RC beam. Based on the fracture energy measured in this study, Modified Compression Field Theory (MCFT) theory-applied Vector 2 program was employed to predict the degree of reduction in shear strength without considering stirrups. Reduction factors were presented based on the obtained results to predict the reduction in shear strength due to interfaces before initial setting of the concrete.

Neurogenic vasoreactive response of human internal thoracic artery smooth muscle.

PubMed

Canver, C C; Cooler, S D; Saban, R

1997-09-01

The interaction between primary afferent neurons containing neuropeptides and the vascular smooth muscle is incompletely understood. To explore the function of perivascular afferent neurons and to determine whether they produce local effects on vascular smooth muscle cells, we investigated the effects of acute capsaicin and substance P administration in vitro on human internal thoracic arteries (ITA). Vessels were obtained from patients undergoing coronary bypass or from multiorgan transplant donors. Fourteen ITA segments (5 mm wide) were suspended as rings between two stainless-steel stirrups in water-jacketed (37 degrees C) tissue baths under 2.5 to 3 g of basal tension. The tissue baths contained 10 mL physiological salt solution (PSS) of the following composition (mM): NaCl, 119; KCl, 4.7; NaH2PO4, 1.0; MgCl2, 0.5; CaCl2, 2.5; NaHCO3, 25; and glucose, 11; aerated continuously with 95% O2 and 5% CO2. Peptidase inhibitors (phosphoramidon and captopril) were added to PSS to decrease peptide degradation. Mechanical responses were measured isometrically and recorded on a polygraph via isotonic force transducers. Vessels were preconstricted with submaximal concentrations of norepinephrine. After the tension had stabilized, substance P or capsaicin was added cumulatively to the tissue bath. At the end of the experiments, the viability of ITA was verified by its responses to endothelial-dependent (acetylcholine) and endothelial-independent (sodium nitroprusside) vasodilators. In the endothelium-intact ITA segments, substance P produced relaxation of ITA smooth muscle while it induced slight contraction when the ITA was devoid of its endothelium (P = 0.0585). The addition of capsaicin to human ITA primarily produced contractile effects on the developed smooth muscle force. The capsaicin-induced contraction of the ITA smooth muscle was independent of endothelial cell integrity, although contraction was greater in the endothelium-intact ITA segments (P = 0.0165). The acute capsaicin exposure of human ITA revealed that primary afferent neurons containing neuropeptides innervate human ITAs. There is a real potential for perivascular afferent neurons and sensory peptides to influence the ITA smooth muscle function.

Influence of seating styles on head and pelvic vertical movement symmetry in horses ridden at trot

PubMed Central

Hernlund, Elin; Pfau, Thilo; Haubro Andersen, Pia; Rhodin, Marie

2018-01-01

Detailed knowledge of how a rider’s seating style and riding on a circle influences the movement symmetry of the horse’s head and pelvis may aid rider and trainer in an early recognition of low grade lameness. Such knowledge is also important during both subjective and objective lameness evaluations in the ridden horse in a clinical setting. In this study, inertial sensors were used to assess how different rider seating styles may influence head and pelvic movement symmetry in horses trotting in a straight line and on the circle in both directions. A total of 26 horses were subjected to 15 different conditions at trot: three unridden conditions and 12 ridden conditions where the rider performed three different seating styles (rising trot, sitting trot and two point seat). Rising trot induced systematic changes in movement symmetry of the horses. The most prominent effect was decreased pelvic rise that occurred as the rider was actively rising up in the stirrups, thus creating a downward momentum counteracting the horses push off. This mimics a push off lameness in the hindlimb that is in stance when the rider sits down in the saddle during the rising trot. On the circle, the asymmetries induced by rising trot on the correct diagonal counteracted the circle induced asymmetries, rendering the horse more symmetrical. This finding offers an explanation to the equestrian tradition of rising on the ‘correct diagonal.’ In horses with small pre-existing movement asymmetries, the asymmetry induced by rising trot, as well as the circular track, attenuated or reduced the horse’s baseline asymmetry, depending on the sitting diagonal and direction on the circle. A push off hindlimb lameness would be expected to increase when the rider sits during the lame hindlimb stance whereas an impact hindlimb lameness would be expected to decrease. These findings suggest that the rising trot may be useful for identifying the type of lameness during subjective lameness assessment of hindlimb lameness. This theory needs to be studied further in clinically lame horses. PMID:29621299

Spatial Organization of the Core Region of Yeast TFIIIB-DNA Complexes

PubMed Central

Persinger, Jim; Sengupta, Sarojini M.; Bartholomew, Blaine

1999-01-01

The interaction of yeast TFIIIB with the region upstream of the SUP4 tRNATyr gene was extensively probed by use of photoreactive phosphodiesters, deoxyuridines, and deoxycytidines that are site specifically incorporated into DNA. The TATA binding protein (TBP) was found to be in close proximity to the minor groove of a TATA-like DNA sequence that starts 30 nucleotides upstream of the start site of transcription. TBP was cross-linked to the phosphate backbone of DNA from bp −30 to −20 in the nontranscribed strand and from bp −28 to −24 in the transcribed strand (+1 denotes the start site of transcription). Most of the major groove of DNA in this region was shown not to be in close proximity to TBP, thus resembling the binding of TBP to the TATA box, with one notable exception. TBP was shown to interact with the major groove of DNA primarily at bp −23 and to a lesser degree at bp −25 in the transcribed strand. The stable interaction of TBP with the major groove at bp −23 was shown to require the B" subunit of TFIIIB. The S4 helix and flanking region of TBP were shown to be proximal to the major groove of DNA by peptide mapping of the region of TBP cross-linked at bp −23. Thus, TBP in the TFIIIB-SUP4 gene promoter region is bound in the same direction as TBP bound to the TATA box with respect to the transcription start site. The B" and TFIIB-related factor (BRF) subunits of TFIIIB are positioned on opposite sides of the TBP-DNA core of the TFIIIB complex, as indicated by correlation of cross-linking data to the crystal structure of the TBP-TATA box complex. Evidence is given for BRF binding near the C-terminal stirrup of TBP, similar to that of TFIIB near the TBP-TATA box complex. The protein clamp formed around the TBP-DNA complex by BRF and B" would help explain the long half-life of the TFIIIB-DNA complex and its resistance to polyanions and high salt. The path of DNA traversing the surface of TBP at the 3′ end of the TATA-like element in the SUP4 tRNA gene is not the same as that of TBP bound to a TATA box element, as shown by the cross-linking of TBP at bp −23. PMID:10373570

Rehabilitation for ankle fractures in adults.

PubMed

Lin, Chung-Wei Christine; Donkers, Nicole A J; Refshauge, Kathryn M; Beckenkamp, Paula R; Khera, Kriti; Moseley, Anne M

2012-11-14

Rehabilitation after ankle fracture can begin soon after the fracture has been treated, either surgically or non-surgically, by the use of different types of immobilisation that allow early commencement of weight-bearing or exercise. Alternatively, rehabilitation, including the use of physical or manual therapies, may start following the period of immobilisation. This is an update of a Cochrane review first published in 2008. To assess the effects of rehabilitation interventions following conservative or surgical treatment of ankle fractures in adults. We searched the Specialised Registers of the Cochrane Bone, Joint and Muscle Trauma Group and the Cochrane Rehabilitation and Related Therapies Field, CENTRAL via The Cochrane Library (2011 Issue 7), MEDLINE via PubMed, EMBASE, CINAHL, PEDro, AMED, SPORTDiscus and clinical trials registers up to July 2011. In addition, we searched reference lists of included studies and relevant systematic reviews. Randomised and quasi-randomised controlled trials with adults undergoing any interventions for rehabilitation after ankle fracture were considered. The primary outcome was activity limitation. Secondary outcomes included quality of life, patient satisfaction, impairments and adverse events. Two review authors independently screened search results, assessed risk of bias and extracted data. Risk ratios and 95% confidence intervals (95% CIs) were calculated for dichotomous variables, and mean differences or standardised mean differences and 95% CIs were calculated for continuous variables. End of treatment and end of follow-up data were presented separately. For end of follow-up data, short term follow-up was defined as up to three months after randomisation, and long-term follow-up as greater than six months after randomisation. Meta-analysis was performed where appropriate. Thirty-eight studies with a total of 1896 participants were included. Only one study was judged at low risk of bias. Eight studies were judged at high risk of selection bias because of lack of allocation concealment and over half the of the studies were at high risk of selective reporting bias.Three small studies investigated rehabilitation interventions during the immobilisation period after conservative orthopaedic management. There was limited evidence from two studies (106 participants in total) of short-term benefit of using an air-stirrup versus an orthosis or a walking cast. One study (12 participants) found 12 weeks of hypnosis did not reduce activity or improve other outcomes.Thirty studies investigated rehabilitation interventions during the immobilisation period after surgical fixation. In 10 studies, the use of a removable type of immobilisation combined with exercise was compared with cast immobilisation alone. Using a removable type of immobilisation to enable controlled exercise significantly reduced activity limitation in five of the eight studies reporting this outcome, reduced pain (number of participants with pain at the long term follow-up: 10/35 versus 25/34; risk ratio (RR) 0.39, 95% confidence interval (CI) 0.22 to 0.68; 2 studies) and improved ankle dorsiflexion range of motion. However, it also led to a higher rate of mainly minor adverse events (49/201 versus 20/197; RR 2.30, 95% CI 1.49 to 3.56; 7 studies).During the immobilisation period after surgical fixation, commencing weight-bearing made a small improvement in ankle dorsiflexion range of motion (mean difference in the difference in range of motion compared with the non-fractured side at the long term follow-up 6.17%, 95% CI 0.14 to 12.20; 2 studies). Evidence from one small but potentially biased study (60 participants) showed that neurostimulation, an electrotherapy modality, may be beneficial in the short-term. There was little and inconclusive evidence on what type of support or immobilisation was the best. One study found no immobilisation improved ankle dorsiflexion and plantarflexion range of motion compared with cast immobilisation, but another showed using a backslab improved ankle dorsiflexion range of motion compared with using a bandage.Five studies investigated different rehabilitation interventions following the immobilisation period after either conservative or surgical orthopaedic management. There was no evidence of effect for stretching or manual therapy in addition to exercise, or exercise compared with usual care. One small study (14 participants) at a high risk of bias found reduced ankle swelling after non-thermal compared with thermal pulsed shortwave diathermy. There is limited evidence supporting early commencement of weight-bearing and the use of a removable type of immobilisation to allow exercise during the immobilisation period after surgical fixation. Because of the potential increased risk of adverse events, the patient's ability to comply with the use of a removable type of immobilisation to enable controlled exercise is essential. There is little evidence for rehabilitation interventions during the immobilisation period after conservative orthopaedic management and no evidence for stretching, manual therapy or exercise compared to usual care following the immobilisation period. Small, single studies showed that some electrotherapy modalities may be beneficial. More clinical trials that are well-designed and adequately-powered are required to strengthen current evidence.