A randomized crossover trial was designed to investigate the influence of muscle activation and strength on functional stability/control of the knee joint, to determine whether bilateral imbalances still occur six months after successful anterior cruciate ligament reconstruction (ACLR), and to analyze whether the use of orthotic devices changes the activity onset of these muscles. Furthermore, conclusions on the feedforward and feedback mechanisms are highlighted. Therefore, twenty‑eight patients will take part in a modified Back in Action (BIA) test battery at an average of six months after a primary unilateral ACLR, which used an autologous ipsilateral semitendinosus tendon graft. This includes double‑leg and single‑leg stability tests, double‑leg and single‑leg countermovement jumps, double‑leg and single‑leg drop jumps, a speedy jump test, and a quick feet test. During the tests, gluteus medius and semitendinosus muscle activity are analyzed using surface electromyography (sEMG). Motion analysis is conducted using Microsoft Azure DK and 3D force plates. The tests are performed while wearing knee rigid orthosis, soft brace, and with no aid, in random order. Additionally, the range of hip and knee motion and hip abductor muscle strength under isometric conditions are measured. Furthermore, patient‑rated outcomes will be assessed.
Die Konzentration von elektronischen und mechanischen Komponenten auf einer Leiterplatte (z.B. Main board) nimmt ständig zu. Dies führt zu höheren Verlustleistungsdichten und somit zu strengeren Anforderungen an das thermische Management. In momentanen und zukünftigen luftgekühlten Anwendungen wird, neben der reinen konduktiven Interaktion zwischen elektronischen Komponenten über die Leiterplatte, zukünftig auch die fluidische Interaktion der natürlichen und forcierten Konvektion während des Leiterplattendesigns mit zu berücksichtigen sein. Der Schaltkreisentwickler benötigt hier zusätzliche Informationen über die thermo-fluidisch gekoppelten Einflüsse zwischen den kritischen wärmedissipierenden Komponenten sowie fluidischer Überlagerungen in Folge anderer angrenzender Komponenten oder mechanischer Komponentengehäuse. In der Vergangenheit wurden zahlreiche Benchmark-Studien zu konvektiven und konduktiven thermischen Interaktionen für verschiedene kommerziell erhältliche mikroelektrische Gehäusetypen veröffentlicht. Heutzutage hat sich die Flip-Chip (FC) Aufbautechnologie von ungehäusten Chips (bare dies) etabliert. Von daher besteht der Bedarf für eine thermische Benchmark Studie für FC Aufbauten. Die vorliegende Studie untersucht die natürlichen und forcierten thermo-fluidischen Einflüsse zwischen ungehäusten FC’s und anderen Komponenten, welche auf mehreren Testleiterplattendesigns aufgebaut und mit der CFD-Simulation verglichen wurden. Ein Vergleich der ersten analysierten Scenarios zeigt eine nachvollziehbare Übereinstimmung zwischen den experimentellen und den Simulationsergebnissen.
This paper deals with the development of an innovative test stand for the measurement of thermal and electrical conductivity of metals, semiconductors, highly conductive die attaches and substrates using the steady state technique for thermal characterization and four-terminal sensing with pulse delta technique for electrical characterization. We present a systematic study of sintered silver in order to investigate the influence of sintering conditions on thermal and electrical properties. Several
sintered silver samples have been prepared under sintering temperature variation between 200°C and 270°C and sintering
pressure variation between 5 MPa and 25 MPa. The characterization results diversify up to 200% for thermal conductivity and up to 330% for electrical conductivity. The Wiedemann-France law describes the relationship between electrical and thermal conductivities for bulk metals. We proved that this law applies not only for bulk metal but also for porous sintered metal.
The Influence of the Special Throwing Technique on the Prevalence of Knee Joint Injuries in Judo
(2014)
Background
There continues to be a lack of evidence to support physiotherapeutic rehabilitation measures after total knee arthroplasty (TKA), especially in the area of functional test procedures, which are indispensable for assessing perioperative physiotherapeutic interventions, including their efficacy.
Objective
A multi-stage, randomised, controlled study design is concerned with the establishment of an evidence-based perioperative physiotherapeutic treatment programme to evaluate physical functional test procedures with regard to their predictive value and the efficacy of physiotherapeutic interventions.
Setting The RCT will be realised in a medical clinic in the department of orthopaedics, sports medicine and rehabilitation.
Participants
A first stage will include young, healthy subjects (Group A) and subjects who are due to undergo TKA and are then to be treated with a standard rehabilitation programme (Group B).
Design Selected promising physical functional test procedures will be tested for their reliability. Inter-tester reliability will be determined in Group A. The test-retest reliability at different perioperative timepoints will be determined in Group B.
Measurements
The following test procedures will be investigated for reliability: 10-m walk test, timed up and go, three times sit to stand, isometric maximal force of knee extension, stair climbing and the cumulative leg circumference. In addition, these test procedures will be correlated among each other and with the WOMAC and KSS for selected aspects of validity. In a second stage, the reliable test procedures will be applied to investigate selected promising physiotherapeutic interventions.
Conclusions
The investigation could change perioperative assessments and physiotherapeutic treatment in patients who have undergone TKA.
OBJECTIVES: The symptomatic reduction of exercise-induced delayed onset muscle soreness (DOMS) is of great interest in the fields of Sports Medicine and Physical Therapy. At this time, few therapeutic interventions have proven their effectiveness. One of the most promising interventions is Compression Therapy. The object of this study is Tissue Flossing, a therapeutic short-term compression method and whether its post-exercise application can reduce the extent of perceived DOMS.
DESIGN: randomized, controlled, and double-blind pilot cross-over trial.
METHODS: Participants (n = 17) without any musculoskeletal injuries were recruited from university students. Participants performed an exercise protocol and obtained the intervention subsequently on one of both arms. Participants had to return for a second day to perform the whole procedure again, this time receiving the flossing intervention on the other arm. At both time points their opposite arms served as the control. The primary outcome measure was a patient reported visual analogue scale 100mm.
RESULTS: The mean value of DOMS of the flossed arm was 42mm compared to the non-flossed arm with 48mm. Differences were found to be statistically significant at 24 hours- (p=0,036; α=0.05), as well as at 48 hours post-intervention (p=0,035; α=0.05). Effect sizes were dz=0,408 at 24 hours-and dz=0,411 at 48 hours post-intervention. The clean language effect size was 0.66.
CONCLUSIONS: Tissue flossing appears to be an effective method for treating DOMS which is slightly less effective but much more practicable than gold standard treatment.
The purpose of this study was to investigate if there are still deficits in muscle mass or strength capabilities in elite judo athletes with a history of anterior cruciate ligament reconstruction (ACLR) after their return to the sport. Therefore, bioimpedance analysis, 3D-laser thigh circumference measurement and isokinetic dynamometry in a closed kinetic chain were used. The side-to-side differences were investigated in a group of judo athletes 5 years after ACLR (n=17) and compared with a group of healthy judo athletes (n=27). Neither thigh circumferences, nor muscle masses of the lower extremities differed in formerly injured judo athletes compared to healthy judo athletes. In contrast, isokinetic strength testing showed a significantly larger side-to-side difference of peak muscle force in formerly injured judo athletes (p=0.021). They provided significantly lower peak forces with the formerly injured leg than with the non-injured leg (p<0.001). The authors conclude that strength capabilities, but not body composition, remains altered in recovered judo athletes in mean 5 years after ACLR and definitely after their return to sports. This indicates that the focus of rehabilitation protocols and return to sports assessments should focus more on maximum strength capabilities.