3,481 research outputs found
JUMP-LANDING KINETIC ASYMMETRIES PERSISTED DESPITE SYMMETRIC SQUAT KINETICS IN COLLEGIATE ATHLETES FOLLOWING ACL RECONSTRUCTION
Anterior cruciate ligament (ACL) re-injury rates are high in collegiate athletes. Squats and countermovement jumps (CMJ) are commonly used for assessments and training after ACL reconstruction (ACLR). The purpose was to quantify the differences and correlations in kinetic asymmetries between squats and CMJs in collegiate athletes following ACLR. Fourteen athletes performed 1-2 squats and CMJs within 24-month following ACLR for a total of 25 assessments. Greater kinetic asymmetries showed in CMJs than squats. Kinetic asymmetries strongly correlated between the ascending and descending phases in squats and moderately between the jumping and landing phases in CMJs. Two phases of squats moderately correlated with the jumping phase of CMJs but the landing phase. CMJ kinetic asymmetries should be directly assessed and trained for mitigating ACL re-injury risk
Feature selection for high dimensional imbalanced class data using harmony search
Misclassification costs of minority class data in real-world applications can be very high. This is a challenging problem especially when the data is also high in dimensionality because of the increase in overfitting and lower model interpretability. Feature selection is recently a popular way to address this problem by identifying features that best predict a minority class. This paper introduces a novel feature selection method call SYMON which uses symmetrical uncertainty and harmony search. Unlike existing methods, SYMON uses symmetrical uncertainty to weigh features with respect to their dependency to class labels. This helps to identify powerful features in retrieving the least frequent class labels. SYMON also uses harmony search to formulate the feature selection phase as an optimisation problem to select the best possible combination of features. The proposed algorithm is able to deal with situations where a set of features have the same weight, by incorporating two vector tuning operations embedded in the harmony search process. In this paper, SYMON is compared against various benchmark feature selection algorithms that were developed to address the same issue. Our empirical evaluation on different micro-array data sets using G-Mean and AUC measures confirm that SYMON is a comparable or a better solution to current benchmarks
Transcriptional reprogramming in yeast using dCas9 and combinatorial gRNA strategies
Additional file 3: Figure S2. Time-dependent regulation of reporter gene expression. Data were obtained with a BioLector from the same cultures as used in Supplementary Fig. S1. Indicated strains were targeted at pHMG1 or pOLE1 as in Fig. 1C with controls (ctrl) expressing dCas9 and no gRNA. Data were collected for ~47 hrs and are presented as the average of three biological replicates. A. MFI from strains targeted with the constitutive system is presented per DCW/L (dry cell weight per liter) as a function of time. Blue; control. Green; activation (MCP-VPR). Red; repression (PCP-Mxi1). B. MFI from cultures added 250 ng/mL aTc to activate the inducible system is presented per OD (OD600) over time. Blue; control. Green; activation (dCas9-VPR). Red; repression (dCas9-Mxi1)
Punctured polygons and polyominoes on the square lattice
We use the finite lattice method to count the number of punctured staircase
and self-avoiding polygons with up to three holes on the square lattice. New or
radically extended series have been derived for both the perimeter and area
generating functions. We show that the critical point is unchanged by a finite
number of punctures, and that the critical exponent increases by a fixed amount
for each puncture. The increase is 1.5 per puncture when enumerating by
perimeter and 1.0 when enumerating by area. A refined estimate of the
connective constant for polygons by area is given. A similar set of results is
obtained for finitely punctured polyominoes. The exponent increase is proved to
be 1.0 per puncture for polyominoes.Comment: 36 pages, 11 figure
Improved Animal Model for Vibration Injury Study
Hand-Arm Vibration Syndrome is a debilitating condition that affects millions of power-tool users in the U.S. Research into its etiology has been hampered by deficiencies in animal models used for vibration studies. Our objective was to design an animal vibration injury model that: 1) vibrates only the studied limb, not the body; and 2) avoids anaesthesia, thus allowing purer focus on physiological effects of vibration while reducing pain and distress for the animals, thereby enhancing their well-being. We compared advantages and disadvantages of several models, studying body temperature, body weight, tissue perfusion, vascular pathohistology, and general animal condition. Our model uses an apparatus that limits vibration to one body part and a specially designed cage that minimizes animal stress and suffering, eliminating the need for anaesthesia. It is ideal for the study of vibration injury, providing tissue damaged purely by vibration that can be used for pathohistology and biochemical study.
Vortex Dynamics and Defects in Simulated Flux Flow
We present the results of molecular dynamic simulations of a two-dimensional
vortex array driven by a uniform current through random pinning centers at zero
temperature. We identify two types of flow of the driven array near the
depinning threshold. For weak disorder the flux array contains few dislocation
and moves via correlated displacements of patches of vortices in a {\it
crinkle} motion. As the disorder strength increases, we observe a crossover to
a spatially inhomogeneous regime of {\it plastic} flow, with a very defective
vortex array and a channel-like structure of the flowing regions. The two
regimes are characterized by qualitatively different spatial distribution of
vortex velocities. In the crinkle regime the distribution of vortex velocities
near threshold has a single maximum that shifts to larger velocities as the
driving force is increased. In the plastic regime the distribution of vortex
velocities near threshold has a clear bimodal structure that persists upon
time-averaging the individual velocities. The bimodal structure of the velocity
distribution reflects the coexistence of pinned and flowing regions and is
proposed as a quantitative signature of plastic flow.Comment: 12 pages, 13 embedded PostScript figure
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