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The use of interfacial layers to stabilize the lithium surface is a popular research direction for improving the morphology of deposited lithium and suppressing lithium dendrite formation. This work considers a different approach to controlling dendrite formation where lithium is plated underneath an interfacial coating. In the present research, a Li–Sn intermetallic was chosen as a model system due to its lithium-rich intermetallic phases and high Li diffusivity. These coatings also exhibit a significantly higher Li exchange current than bare Li thus leading to better charge transfer kinetics. The exchange current is instrumental in determining whether lithium deposition occurs above or below the Li–Sn coating. High-resolution transmission electron microscopy and cryogenic focused ion beam scanning electron microscopy were used to identify the features associated with Li deposition. Atomic scale simulations provide insight as to the adsorption energies determining the deposition of lithium below the Li–Sn coating.

Hemiarthroplasty (HA) for proximal humerus fracture (PHF) is associated with tuberosity complications like migration, non-union, and resorption. In order to improve the rate of consolidation of the greater tuberosity (GT), we have developed a hollow humeral head prosthesis in which the whole humeral head is inserted and used as autograft. This study is designed to evaluate the consolidation rate of the GT with this device. Twenty-two patients at mean age of 68 were treated between 2015 and 2017 for four-part fractures, fracture-dislocations, and head-split fractures with HA including the bony humeral head. The humeral prosthesis device comprises a prosthetic cephalic cup in which the detached humeral head is inserted and a cementless adjustable humeral stem which works like a jack. Mean follow-up was 14 months. The consolidation of GT was followed on X-rays. As comparison, 15 published series were selected and analyzed. There were two mechanical complications related to GT consolidation (9.1%). In the 20 other cases, the GT was radiologically consolidated without displacement. While the raw proportion of complications observed in the present series was lower than that reported in each of the 15 comparative series, the proportion of complications observed in the present series was significantly different from that observed only in seven out of the 15 previous series. Whole conservation of the humeral head as an autograft along with proper surgical technique yielded in 20 consolidations of GT without displacement in 22 cases of PHF treated with hemiarthroplasty.

Nicolai Foss and Peter Klein have penned a most remarkable book on the theory of the firm. They offer a rich analysis of the economic organization through the lenses of various approaches including Austrian economics and neo-institutional economics. Their work is a welcome addition to the field of entrepreneurship studies, as it focuses on the role of entrepreneurship within established organizations. While I embrace most of the authors’ conclusions, I disagree with a central piece of their analysis: The rejection of the Kirznerian framework. In establishing judgment as the fundamental explanans of the theory of entrepreneurship, Foss and Klein introduce the bias of seeing entrepreneurship as allocating resources in firms. Moreover, introducing the process of judgment does not offer new insights that cannot be obtained through Kirznerian discovery analysis. Fundamentally, the essence of entrepreneurship is at stake. And it is not a debate about semantics. It is my contention that Israel Kirzner offers a more fundamental theory of entrepreneurship — one that can be applied within and beyond the realm of the firm, and that helps us explain social change, market processes, development, and growth.

Background Accumulation of advanced glycation end-products (AGEs) is involved in age-related osteoarthritis (OA). Glyoxalase (Glo)-1 is the main enzyme involved in the removal of AGE precursors, especially carboxymethyl-lysine (CML). We aimed to investigate the expression of several AGEs and Glo-1 in human OA cartilage and to study chondrocytic Glo-1 regulation by inflammation, mediated by interleukin (IL)-1β. Methods Ex vivo, we quantified AGEs (pentosidine, CML, methylglyoxal-hydroimidazolone-1) in knee cartilage from 30 OA patients. Explants were also incubated with and without IL-1β, and we assessed Glo-1 protein expression and enzymatic activity. In vitro, primary cultured murine chondrocytes were stimulated with increasing concentrations of IL-1β to assess Glo-1 enzymatic activity and expression. To investigate the role of oxidative stress in the IL-1β effect, cells were also treated with inhibitors of mitochondrial oxidative stress or nitric oxide synthase. Results Ex vivo, only the human cartilage CML content was correlated with patient age (r = 0.78, p = 0.0031). No statistically significant correlation was found between Glo-1 protein expression and enzymatic activity in human cartilage and patient age. We observed that cartilage explant stimulation with IL-1β decreased Glo-1 protein expression and enzymatic activity. In vitro, we observed a dose-dependent decrease in Glo-1 mRNA, protein quantity, and enzymatic activity in response to IL-1β in murine chondrocytes. Inhibitors of oxidative stress blunted this downregulation. Conclusion Glo-1 is impaired by inflammation mediated by IL-1β in chondrocytes through oxidative stress pathways and may explain age-dependent accumulation of the AGE CML in OA cartilage. Electronic supplementary material The online version of this article (10.1186/s13075-018-1801-y) contains supplementary material, which is available to authorized users.

Posterior shoulder dislocations are rare, and are usually the result of seizures. Anterior defects of the humeral head known as "reverse Hill-Sachs lesions" may increase the risk of recurrent dislocation and are difficult to treat. We developed a percutaneous technique for reduction of the dislocation or reduction of the anterior impaction fracture, using percutaneous balloon dilatation and cement fixation.From 2009 to 2012, three patients aged 33, 72 and 75 years were admitted to our institution with a posterior shoulder dislocation showing an anterior "reverse Hill-Sachs" impaction fracture. One case was bilateral (four fractures). Patients were operated upon in the sitting position; the humeral head was stabilised by external fixator pins during balloon inflation. Reduction or filling of the defect was obtained in all cases. All patients were followed up and two patients (three fractures) were examined after one year by an independent observer. The clinical results were assessed using the Constant score and the RAND-36 physical components score. A computed tomography (CT) scan was obtained in all patients before and after the operation and at the latest follow-up.At three months postoperatively, all patients had resumed work or daily life activities with no limitation. The mean Constant score was 71 and RAND-36 score was 85.5. After one year, the mean Constant score was 73 and the RAND-36 score was 86.4 for the two patients who had sufficient follow-up. On the postoperative radiograph and CT scan, sphericity of the humeral head was restored, and the reverse Hill-Sachs impaction was filled or reduced in all cases. There was no recurrent dislocation.Based on this small series, we believe that this technique should be added to our current armamentarium for posterior shoulder dislocations showing a deep impaction fracture of the humeral head that are at risk for recurrent dislocation.

An entrepreneur’s prior knowledge and experience play a critical role in his ability to identify and exploit entrepreneurial opportunities. Although entrepreneurship research has acknowledged the role that prior information and prior knowledge play in opportunity recognition, few studies have explored their role in entrepreneurial discovery. We test the role of a particular prior knowledge in entrepreneurial discovery within a laboratory setting. Participants were randomly assigned to one of two treatment groups. Those in the propitious treatment were given prior knowledge that oriented them toward the arbitrage opportunity within the experiment, and those in the unpropitious treatment were given prior knowledge that oriented them away. As hypothesized, those in the propitious treatment were significantly more likely to discover the arbitrage opportunity.

Smartphones have gained widespread use in the healthcare field to fulfill a variety of tasks. We developed a small iPhone application to take advantage of the built-in position sensor to measure angles in a variety of spinal deformities. We present a reliability study of this tool in measuring kyphotic angles.Radiographs taken from 20 different patients' charts were presented to a panel of six operators at two different times. Radiographs were measured with the protractor and the iPhone application and statistical analysis was applied to measure intraclass correlation coefficients between both measurement methods, and to measure intra- and interobserver reliabilityThe intraclass correlation coefficient calculated between methods (i.e. CobbMeter application on the iPhone versus standard method with the protractor) was 0.963 for all measures, indicating excellent correlation was obtained between the CobbMeter application and the standard method. The interobserver correlation coefficient was 0.965. The intraobserver ICC was 0.977, indicating excellent reproductibility of measurements at different times for all operators. The interobserver ICC between fellowship trained senior surgeons and general orthopaedic residents was 0.989. Consistently, the ICC for intraobserver and interobserver correlations was higher with the CobbMeter application than with the regular protractor method. This difference was not statistically significant.Measuring kyphotic angles with the iPhone application appears to be a valid procedure and is in no way inferior to the standard way of measuring the Cobb angle in kyphotic deformities.

This paper presents an experimental study of flow development and structure on a separated jet burner in reacting and non-reacting flows. Effects of deflection jets in an aligned configuration of three round jets are emphasized. The idea is based on the confinement of a central jet of fuel by two side jets of oxygen to improve mixing, to control flame stability, and to reduce pollutant emissions. The fields of mean velocity and fluctuation intensity were measured using Particle Image Velocimetry. The deflection of jets has a considerable effect on the dynamic behavior and on the flame characteristics. Results showed that the deflection of jets favors mixing and accelerates merging and combining of jets to a single one. Measurements in reacting flow showed a high influence of combustion on dynamic fields. Compared to non-reactive case, in combustion, larger radial expansion and higher velocity were observed, particularly, above the stabilization point of the flame.

The properties of hydroxyl groups on γ-Al2O3, TiO2-anatase and MgO are rationalized by Density Functional Theory calculations. Oxide ionicity is found to be determinant in the water/oxide interaction strength when dissociation of H2O occurs, and in the bridging ability of monocoordinated surface OH groups. For a hydroxyl, being the hydrogen bond donor, acceptor or having an isolated nature is found to be the most important parameter governing the O–H stretching frequency.

By grafting well-defined metallic complexes on a solid support, surface organometallic chemistry provides a bridge between homogeneous and heterogeneous catalysis. This innovative approach has already proven its efficiency for several reactions: polymerization, olefin and alkane metathesis… However several fundamental questions remain open on the chemical role of the oxide surface, on the grafting mechanism and on the reactivity of the grafted complex. Is a single well-defined surface/metal/ligand complex formed? Is the solid surface just an inert support, or does it play an active chemical role? We combine on the one hand reactivity and spectroscopic experiments with on the other hand total energy calculations and spectra simulations (NMR, IR) in order to propose insights for these open questions, using the example of [Zr(CH2 tBu)4] complex grafted on partially dehydroxylated gamma-alumina. A molecular level approach to the grafting mechanism is proposed. Alumina plays a dual role, both as support and Lewis acid co-catalyst. The hydroxyl groups permit the covalent grafting through Al–O–Zr linkages, while the neighboring Al Lewis sites allow the formation of an ion pair, by transfer of an alkyl ligand from the Zr toward the Al. The formed cationic Zr center shows an enhanced electrophilic character. The mechanism of the formation of the Zr hydride supported on alumina, upon treatment under H2 gas is described, with the formation of a mixture of mono-hydride (Zr+–H; Al−–CH2 tBu) and bis-hydride (Zr+–H; Al−–H). This Zr hydride supported on alumina is active for butane hydrogenolysis. A mechanism with reasonable energy barriers is proposed, the rate limiting step being the C–C scission.

With the collapse of communism in the late 1980s the field of comparative political economy has undergone major revision. Socialism is no longer considered the viable alternative to capitalism it once was. We now recognize that the choice is between alternative institutional arrangements of capitalism. Progress in the field of comparative political economy is achieved by examining how different legal, political and social institutions shape economic behavior and impact economic performance. In this paper we survey the new learning in comparative political economy and suggest how this learning should redirect our attention in economic development.

The anatomy and embryology of the aortic arch and its branching tributaries (brachiocephalic trunk, left common carotid artery and left subclavian artery) in man and animals are well substantiated. However, the anatomical variations and morphometry of the aortic arch and its branching tributaries in rat fetus at the 21st gestation day have not been studied. Pregnant rats were hysterectomized and the arterial systems of 114 fetuses were injected with a polymerisable resin through the umbilical artery. After maceration, the vascular casts were dissected out and prepared for observations under a scanning electron microscope (SEM). The resulting SEM pictures were studied with a picture analyser and different vessel parameters (diameters, lengths and angles) were measured. The success rate of the microvascular cast injection was 46.5%. Out of the 53 observed aortic arch casts, 98.1% showed the classical branching pattern and one (1.9%) had no brachiocephalic trunk. Morphological analysis showed many differences, which were not linked to the litter. The statistical processing of the measurements enabled us to determine that the aorta diameter after the branching of the left subclavian artery was the most replicable parameter. Moreover, the results revealed some strong correlations between different parameters. There are probably no discrete categories among the various observed parameters as diameters and angles. Some parameters show very little variability and can thus be used as reference points for further studies such as the comparison of a control population with a population treated with a relevant xenobiotic.

Pulsed laser Mie scattering and laser Doppler velocimetry (LDV), both conditioned on the origin of the seed particles, have been successively performed in turbulent jets with variable density. In the early stages of the jet developments, significant differences are measured between the ensemble average LDV data obtained by jet seeding and those obtained by seeding the ambient air. Careful analysis of the marker statistics shows that this difference is a quantitative measure of the turbulent mixing. The good agreement with gradient–diffusion modelling suggests the validity of a general diffusion equation where the velocities involved are expressed in terms of ensemble conditional Favre averages. This operator accounts for all events (including intermittent ones) and for variations in the density of the marked fluid whose velocity is still specified by the binary origin of the marker.

Reaching high selectivities is an important concern for heterogeneous catalysis. Insights in the factors which control the reaction selectivity can be obtained from theoretical approaches, also a full computational description of the reaction is not yet possible, due to the great complexity of the molecules generally involved in fine chemical catalysis. Some theoritical works related to the interpretation of chemical selectivity are rewieved in this paper, with a focus on the various types of selectivity: chemoselectivity, regioselectivity and enantioselectivity.

A single-shot laser Mie scattering technique is used to measure the instantaneous radial distributions of seed particles in the early development zone of turbulent jets with various bulk densities issuing into a slow coflowing air stream. Instantaneous radial profiles of mixture fraction are derived from the measured distributions with either the jet fluid or only the coflow air seeded, depending on the investigated zone. Radial gradients and autocorrelation profiles are analyzed to study the scalar dissipation and the mixing length scale respectively. Self-similar behaviour is investigated by plotting the centreline scalar decay as a function of a reduced abscissa, which accounts for the axial variation of the jet density in its early development. As the density is simultaneously derivable from the mixture fraction data, direct comparisons between Favre and Reynolds averaged values are obtained which show very significant differences in the near field.

The different low temperature coordination modes of ethylene and butadiene on a platinum (111) face, (110) face and on a palladium (111) face are compared on the basis of extended Huckel calculations. The nature of the chemical interaction between the olefin and the surface is detailed and the electronic factors that govern the coordination mode of the hydrocarbon are underlined. The different surfaces are modelled by a 49 or a 44 atoms cluster. A correction is applied in the calculation in order to minimize the artefact introduced by this cluster representation of an extended surface. For the adsorption, the respective importance of two electrons interactions and four electrons repulsions is the key point for the determination of the preferred mode. The di-σ coordination is more stable on platinum (111) but on the platinum (110) face the π coordination yields the same adsorption energy than the di-σ one. This is roughly the same result for the palladium (111) face. The π mode is there favored by a decrease of the four electrons repulsions caused either by a smaller number of metal neighbours for the surface atom (Pt(110)) or by a reduced radial expansion of the metal orbitals (Pd(111)). This π coordination is associated with a smaller hybridization of the ethylene molecule. The results are extended to the adsorption of butadiene and this allows a qualitative explanation of the better selectivity for butadiene partial hydrogenation on palladium compared with platinum.

Decay laws in the initial, non buoyant region of round, turbulent, variable density jets can be derived from dimensional similarity considerations. This paper presents the concept of normalized effective diameter. In the case of turbulent jets issuing into a coflow air stream (initial density ratio varying from 0.07 to 1), this quantity is experimentally derived from measurements of mean density and velocity and is found to follow a unique exponential decay. Results are also presented in terms of global force of the nozzle fluid.