Comparing revision rates and survival of pyrocarbon and non-pyrocarbon heads in total shoulder and hemi-shoulder arthroplasty.

Objective: This retrospective, observational study aimed to assess the revision rates and survival curves in total shoulder arthroplasty (TSA) and hemi-shoulder arthroplasty (HSA) patients, including a subanalysis to investigate the impact of a pyrocarbon humeral head in revision rates.

Methods: Data collected from 7 surgeons who performed primary HSA in 92 patients and primary TSA in 508 patients at a large private clinic were analyzed. The study focused on revision rates and identified factors leading to revisions, including rotator cuff insufficiency, dislocation, aseptic loosening, implant material, and glenoid erosion.

Model Virtues in Computational Cognitive Neuroscience.

There is an abundance of computational models in cognitive neuroscience. A framework for what is desirable in a model, what justifies the introduction of a new one, or what makes one better than another is lacking, however. In this article, we examine key qualities ("virtues") that are desirable in computational models, and how these are interrelated.

Depletion-Induced Chiral Chain Formation of Magnetic Spheres.

Experimental evidence is presented for the spontaneous formation of chiral configurations in bulk dispersions of magnetized colloids that interact by a combination of anisotropic dipolar interactions and isotropic depletion attractions. The colloids are superparamagnetic silica spheres, magnetized and aligned by a carefully tuned uniform external magnetic field; isotropic attractions are induced by using poly(ethylene oxide) polymers as depleting agents. At specific polymer concentrations, sphere chains wind around each other to form helical structures-of the type that previously have only been observed in simulations on small sets of unconfined dipolar spheres with additional isotropic interactions.

The Impact of Human-Robot Synchronization on Anthropomorphization.

To elucidate the working mechanism behind anthropomorphism, this study investigated whether human participants would anthropomorphize a robot more if they move synchronously versus non-synchronously with it, and whether this is affected by which of the two initiates the movements. We tested two competing hypotheses. The feature-overlap hypothesis predicts that moving in synchrony would increase perceived self-other feature overlap, which in turn might spread activation to codes of features related to humans-which should increase anthropomorphization.

Accurate Measurement of the in vivo Ammonium Concentration in Saccharomyces cerevisiae.

Ammonium (NH₄⁺) is the most common N-source for yeast fermentations, and N-limitation is frequently applied to reduce growth and increase product yields. While there is significant molecular knowledge on NH₄⁺ transport and assimilation, there have been few attempts to measure the in vivo concentration of this metabolite. In this article, we present a sensitive and accurate analytical method to quantify the in vivo intracellular ammonium concentration in Saccharomyces cerevisiae based on standard rapid sampling and metabolomics techniques.

Neuromodulation of Aerobic Exercise-A Review.

Running, and aerobic exercise in general, is a physical activity that increasingly many people engage in but that also has become popular as a topic for scientific research. Here we review the available studies investigating whether and to which degree aerobic exercise modulates hormones, amino acids, and neurotransmitters levels. In general, it seems that factors such as genes, gender, training status, and hormonal status need to be taken into account to gain a better understanding of the neuromodular underpinnings of aerobic exercise.

How to obtain true and accurate rate-values.

In metabolic flux calculations, the uptake and secretion rates (for substrate, O(2), CO(2), growth, (by)-products) are essential to arrive at correct calculated fluxes. Surprisingly, a lot of research has been published on the methods of flux calculations, but much less attention has been spent on the methods to obtain accurate and true uptake and secretion rates which are used as input. Therefore, this contribution focuses on.

Possible pitfalls of flux calculations based on (13)C-labeling.

Metabolic engineers have enthusiastically adopted the (13)C-labeling technique as a powerful tool for elucidating fluxes in metabolic networks. This tracer technique makes it possible to determine fluxes that are unobservable using only metabolite balances and allows the elimination of doubtful cofactor balances that are indispensable in flux analysis based on metabolite balancing alone. The (13)C-labeling technique, however, relies on a number of assumptions that are not free from uncertainties.

Tendency modeling: a new approach to obtain simplified kinetic models of metabolism applied to Saccharomyces cerevisiae.

A novel approach to construct kinetic models of metabolic pathways, to be used in metabolic engineering, is presented: the tendency modeling approach. This approach greatly facilitates the construction of these models and can easily be applied to complex metabolic networks. The resulting models contain a minimal number of parameters; identification of their values is straightforward.

Particle-based biofilm reactor technology.

Particle-based biofilm reactors provide the potential to develop compact and high-rate processes. In these reactors, a large biomass content can be maintained (up to 30 g l-1), and the large specific surface area (up to 3000 m2 m-3) ensures that the conversions are not strongly limited by the biofilm liquid mass-transfer rate. Engineered design and control of particle-based biofilm reactors are established, and reliable correlations exist for the estimation of the design parameters.

Anatomical distribution of the chemorepellent semaphorin III/collapsin-1 in the adult rat and human brain: predominant expression in structures of the olfactory-hippocampal pathway and the motor system.

Alterations in neuronal connectivity of the mature central nervous system (CNS) appear to depend on a delicate balance between growth-promoting and growth-inhibiting molecules. To begin to address a potential role of the secreted chemorepulsive protein semaphorin(D)III/collapsin-1 (semaIII/coll-1) in structural plasticity during adulthood, we used high-resolution nonradioactive in situ hybridization to identify neural structures that express semaIII/coll-1 mRNA in the mature rat and human brain. SemaIII/coll-1 was expressed in distinct but anatomically and functionally linked structures of the adult nervous system.

Validation of a metabolic network for Saccharomyces cerevisiae using mixed substrate studies.

Setting up a metabolic network model for respiratory growth of Saccharomyces cerevisiae requires the estimation of only two (energetic) stoichiometric parameters: (1) the operational PO ratio and (2) a growth-related maintenance factor k. It is shown, both theoretically and practically, how chemostat cultivations with different mixtures of two substrates allow unique values to be given to these unknowns of the proposed metabolic model. For the yeast and model considered, an effective PO ratio of 1.

Regulation of carbon metabolism in chemostat cultures of Saccharomyces cerevisiae grown on mixtures of glucose and ethanol.

Growth efficiency and regulation of key enzyme activities were studied in carbon- and energy-limited chemostat cultures of Saccharomyces cerevisiae grown on mixtures of glucose and ethanol at a fixed dilution rate. Biomass yields on substrate carbon and oxygen could be adequately described as the net result of growth on the single substrates. Activities of isocitrate lyase and malate synthase were not detected in cell-free extracts of glucose-limited cultures.