Author Correction: WNT-activated bone grafts repair osteonecrotic lesions in aged animals.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Biomechanical Implications of an Oblique Knee Joint Line.

Surgical correction of multiapical deformities of the lower limb requires careful preoperative planning. Surgeons must account for the potential creation of secondary deformity, such as knee joint line obliquity, and the risks associated with accepting these changes in limb alignment. In this study, we evaluate the effect of knee joint obliquity on tibial plateau contact pressures and knee instability.

WNT-activated bone grafts repair osteonecrotic lesions in aged animals.

The Wnt pathway is a new target in bone therapeutic space. WNT proteins are potent stem cell activators and pro-osteogenic agents. Here, we gained insights into the molecular and cellular mechanisms responsible for liposome-reconstituted recombinant human WNT3A protein (L-WNT3A) efficacy to treat osteonecrotic defects.

Protein adsorption in microengraving immunoassays.

Microengraving is a novel immunoassay for characterizing multiple protein secretions from single cells. During the immunoassay, characteristic diffusion and kinetic time scales  and  determine the time for molecular diffusion of proteins secreted from the activated single lymphocytes and subsequent binding onto the glass slide surface respectively. Our results demonstrate that molecular diffusion plays important roles in the early stage of protein adsorption dynamics which shifts to a kinetic controlled mechanism in the later stage.

Drop impact on a flexible fiber.

When droplets impact fibrous media, the liquid can be captured by the fibers or contact then break away. Previous studies have shown that the efficiency of drop capture by a rigid fiber depends on the impact velocity and a threshold velocity was defined below which the drop is captured. However, it is necessary to consider the coupling of elastic and capillary effects to achieve an improved understanding of the capture process for soft substrates.

Effect of acute ethanol administration on zebrafish tail-beat motion.

Zebrafish is becoming a species of choice in neurobiological and behavioral studies of alcohol-related disorders. In these efforts, the activity of adult zebrafish is typically quantified using indirect activity measures that are either scored manually or identified automatically from the fish trajectory. The analysis of such activity measures has produced important insight into the effect of acute ethanol exposure on individual and social behavior of this vertebrate species.

Bone Homeostasis and Repair: Forced Into Shape.

Mechanical loading is a potent anabolic regulator of bone mass, and the first line of defense for bone loss is weight-bearing exercise. Likewise, protected weight bearing is the first prescribed physical therapy following orthopedic reconstructive surgery. In both cases, enhancement of new bone formation is the goal.

Subject- and resource-specific monitoring and proactive management of parallel radiofrequency transmission.

Purpose: Develop a practical comprehensive package for proactive management of parallel radiofrequency (RF) transmission.

Methods: With a constrained optimization framework and predictive models from a prescan based multichannel calibration, we presented a method supporting design and optimization of parallel RF excitation pulses that accurately obey the forward/reflected peak and average power limits of the RF power amplifiers in parallel transmit imaging experiments and Bloch simulations. Moreover, local SAR limits were incorporated into the parallel RF excitation pulses using electromagnetic field simulations.

Wetting morphologies on randomly oriented fibers.

We characterize the different morphologies adopted by a drop of liquid placed on two randomly oriented fibers, which is a first step toward understanding the wetting of fibrous networks. The present work reviews previous modeling for parallel and touching crossed fibers and extends it to an arbitrary orientation of the fibers characterized by the tilting angle and the minimum spacing distance. Depending on the volume of liquid, the spacing distance between fibers and the angle between the fibers, we highlight that the liquid can adopt three different equilibrium morphologies: 1) a column morphology in which the liquid spreads between the fibers, 2) a mixed morphology where a drop grows at one end of the column or 3) a single drop located at the node.

Hyaluronan, Inflammation, and Breast Cancer Progression.

Breast cancer-induced inflammation in the tumor reactive stroma supports invasion and malignant progression and is contributed to by a variety of host cells including macrophages and fibroblasts. Inflammation appears to be initiated by tumor cells and surrounding host fibroblasts that secrete pro-inflammatory cytokines and chemokines and remodel the extracellular matrix (ECM) to create a pro-inflammatory "cancerized" or tumor reactive microenvironment that supports tumor expansion and invasion. The tissue polysaccharide hyaluronan (HA) is an example of an ECM component within the cancerized microenvironment that promotes breast cancer progression.

The Content and Size of Hyaluronan in Biological Fluids and Tissues.

Hyaluronan is a simple repeating disaccharide polymer, synthesized at the cell surface by integral membrane synthases. The repeating sequence is perfectly homogeneous, and is the same in all vertebrate tissues and fluids. The polymer molecular mass is more variable.

Toward an autonomous brain machine interface: integrating sensorimotor reward modulation and reinforcement learning.

For decades, neurophysiologists have worked on elucidating the function of the cortical sensorimotor control system from the standpoint of kinematics or dynamics. Recently, computational neuroscientists have developed models that can emulate changes seen in the primary motor cortex during learning. However, these simulations rely on the existence of a reward-like signal in the primary sensorimotor cortex.

A polyaniline based ultrasensitive potentiometric immunosensor for cardiac troponin complex detection.

An ultrasensitive immunosensor based on potentiometric ELISA for the detection of a cardiac biomarker, troponin I-T-C (Tn I-T-C) complex, was developed. The sensor fabrication involves typical sandwich ELISA procedures, while the final signal readout was achieved using open circuit potentiometry (OCP). Glassy carbon (GC) working electrodes were first coated with emulsion-polymerized polyaniline/dinonylnaphthalenesulfonic acid (PANI/DNNSA) and the coated surface was utilized as a transducer layer on which sandwich ELISA incubation steps were performed.

Enhancing the speed of morpholino-DNA biosensor by electrokinetic concentration of DNA in a microfluidic chip.

Unlabelled: Electrokinetic methods that conveniently concentrate charged analytes by orders of magnitude are highly attractive for nucleic acid assays where they can bypass the complexity and costs of enzyme-based amplification. The present study demonstrates an electrokinetic concentration device incorporating charge-neutral morpholino (MO) probes: as DNA analyte is concentrated in a microfluidic channel using ion concentration polarization (ICP) it is simultaneously hybridized to spots of complementary MO probes immobilized on the channel floor. This approach is uniquely favored by the match between the optimum buffer ionic strength of approximately 10mM for both MO-DNA surface hybridization and electrokinetic concentration.

Acute caffeine administration affects zebrafish response to a robotic stimulus.

Zebrafish has been recently proposed as a valid animal model to investigate the fundamental mechanisms regulating emotional behavior and evaluate the modulatory effects exerted by psychoactive compounds. In this study, we propose a novel methodological framework based on robotics and information theory to investigate the behavioral response of zebrafish exposed to acute caffeine treatment. In a binary preference test, we studied the response of caffeine-treated zebrafish to a replica of a shoal of conspecifics moving in the tank.

Tunable Conformation-Dependent Engineered Protein·Gold Nanoparticle Nanocomposites.

We demonstrate the fabrication of protein·gold nanoparticle (AuNP) nanocomposites in situ, leading to distinct assemblies dependent upon protein secondary structure. In the presence of pentameric coiled-coil proteins C and Q, which contain histidine tags and have helicities of 54 and 65%, respectively, templation of AuNP results in precipitation of the protein·AuNP composites with AuNPs 6.5 nm in diameter, creating macromolecular assemblies on the micrometer scale.

The effect of geography and citizen behavior on motor vehicle deaths in the United States.

Death due to motor vehicle collisions (MVCs) remains a leading cause of death in the US and alcohol plays a prominent role in a large proportion of these fatalities nationwide. Rates for these incidents vary widely among states and over time. Here, we explore the extent to which driving volume, alcohol consumption, legislation, political ideology, and geographical factors influence MVC deaths across states and time.

Measuring zebrafish turning rate.

Zebrafish is becoming a popular animal model in preclinical research, and zebrafish turning rate has been proposed for the analysis of activity in several domains. The turning rate is often estimated from the trajectory of the fish centroid that is output by commercial or custom-made target tracking software run on overhead videos of fish swimming. However, the accuracy of such indirect methods with respect to the turning rate associated with changes in heading during zebrafish locomotion is largely untested.

Influence of fluorination on protein-engineered coiled-coil fibers.

We describe the design and characterization of fluorinated coiled-coil proteins able to assemble into robust nano- and microfibers. Fluorination is achieved biosynthetically by residue-specific incorporation of 5,5,5-trifluoroleucine (TFL). The fluorinated proteins C+TFL and Q+TFL are highly α-helical as confirmed via circular dichroism (CD) and more resistant to thermal denaturation compared to their nonfluorinated counterparts, C and Q.

Increasing patient engagement in rehabilitation exercises using computer-based citizen science.

Patient motivation is an important factor to consider when developing rehabilitation programs. Here, we explore the effectiveness of active participation in web-based citizen science activities as a means of increasing participant engagement in rehabilitation exercises, through the use of a low-cost haptic joystick interfaced with a laptop computer. Using the joystick, patients navigate a virtual environment representing the site of a citizen science project situated in a polluted canal.

Radiofrequency energy deposition and radiofrequency power requirements in parallel transmission with increasing distance from the coil to the sample.

Purpose: We investigated global specific absorption rate (SAR) and radiofrequency (RF) power requirements in parallel transmission as the distance between the transmit coils and the sample was increased.

Methods: We calculated ultimate intrinsic SAR (UISAR), which depends on object geometry and electrical properties but not on coil design, and we used it as the reference to compare the performance of various transmit arrays. We investigated the case of fixing coil size and increasing the number of coils while moving the array away from the sample, as well as the case of fixing coil number and scaling coil dimensions.

Live predators, robots, and computer-animated images elicit differential avoidance responses in zebrafish.

Emotional disturbances constitute a major health issue affecting a considerable portion of the population in western countries. In this context, animal models offer a relevant tool to address the underlying biological determinants and to screen novel therapeutic strategies. While rodents have traditionally constituted the species of choice, zebrafish are now becoming a viable alternative.

Mechanical tuning of the evaporation rate of liquid on crossed fibers.

We investigate experimentally the drying of a small volume of perfectly wetting liquid on two crossed fibers. We characterize the drying dynamics for the three liquid morphologies that are encountered in this geometry: drop, column, and a mixed morphology, in which a drop and a column coexist. For each morphology, we rationalize our findings with theoretical models that capture the drying kinetics.

Application of global positioning system methods for the study of obesity and hypertension risk among low-income housing residents in New York City: a spatial feasibility study.

The purpose of this study was to evaluate the feasibility of using global positioning system (GPS) methods to understand the spatial context of obesity and hypertension risk among a sample of low-income housing residents in New York City (n = 120). GPS feasibility among participants was measured with a pre- and post-survey as well as adherence to a protocol which included returning the GPS device as well as objective data analysed from the GPS devices. We also conducted qualitative interviews with 21 of the participants.