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The letter discusses a recently published paper on "Diagnostic Imaging of the diabetic foot" which provides a comprehensive summary of the literature on the topic. The paper is helpful for clinicians trying to determine if osteomyelitis is present in diabetic patients. However, the letter points out a flaw in the paper regarding the use of the acronym "PTB" which is not defined clearly and may be unfamiliar to nuclear medicine physicians. The letter author explains that PTB stands for "Probe to Bone" and is a test used to assess for osteomyelitis in diabetic foot ulcers. The author suggests that nuclear medicine physicians may not be aware of this test and recommends further clarification or references in the paper. [Extracted from the article]

Livestock are an important component of livelihoods in smallholder dairy systems in Africa, but are characterized by low animal productivity and large environmental impacts per unit of animal product (e.g. greenhouse gas emissions (GHG) intensities). Governments in African countries have set ambitious targets for dairy systems, but development of climate-smart strategies has been hindered by a scarcity of baseline data and local intervention trials. We use a rich dataset from smallholder mixed dairy systems in Kenya to determine whether national climate and development goals for 2030 can be met using locally appropriate interventions. Interventions considered included improved herd management and feed interventions. We conducted a yield gap analysis to determine the scope of the existing milk yield gaps, then evaluated the extent to which yield gaps could be closed using interventions in a second step. We outscaled our results to the national level to determine the potential impact of adopting our interventions on national dairy production and GHG emission goals using the FAO Global Livestock Environmental Assessment Model – interactive (GLEAM-i) tool. Our analysis showed that substantial yield gaps exist in Kenyan dairy systems (39 to 49% of attainable yields). These gaps could be closed by intervention packages but not by individual interventions alone. Our outscaled scenarios showed interventions can reduce milk GHG emission intensities (−6.5 to −27.4%), while absolute emissions would increase in most scenarios (−3.9 to +25.9%). To meet national milk production goals, we estimated that a large increase in animal numbers is needed by 2030 compared to 2010 (from ∼2.7 M to 4.5–7.1 M heads of cattle). However, most scenarios fell short of the emissions target (−4% to +48%) by 2030. It may be possible to narrowly meet Kenyan national milk production and GHG emission goals by 2030. National goals for milk production and reducing GHG emissions were only marginally compatible in Kenya. Other sectors of the economy will need to reduce emissions to ensure that food and nutrition security objectives are not jeopardized. In order to achieve national milk goals, there will be need to be a consummate increase in animal numbers even with the adoption of multiple interventions. To meet Kenya's national emissions goals, widespread adoption of several locally appropriate interventions will be required. International support will be needed to meet Kenya's conditional Nationally Determined Contributions under the 2015 Paris Agreement, as well as food and nutrition security goals. [Display omitted] • Livestock are a primary source of GHG emissions in African countries, but demand for animal products is increasing. • Assessed milk yield gaps for dairy systems in Kenya and outscaled results to national level to determine milk and climate goals can be reached by 2030 using interventions. • Large milk yield gaps exist in Kenya, but gaps can be at least partially closed using locally appropriate interventions. • At the national scale, locally appropriate interventions reduced GHG emission intensities but increased absolute emissions. • All except one scenario fell short of Kenya's national emissions target by 2030, even with adoption of interventions. [ABSTRACT FROM AUTHOR]

Dissipative partial differential equations that exhibit chaotic dynamics tend to evolve to attractors that exist on finite-dimensional manifolds. We present a data-driven reduced-order modeling method that capitalizes on this fact by finding a coordinate representation for this manifold and then a system of ordinary differential equations (ODEs) describing the dynamics in this coordinate system. The manifold coordinates are discovered using an undercomplete autoencoder—a neural network (NN) that reduces and then expands dimension. Then, the ODE, in these coordinates, is determined by a NN using the neural ODE framework. Both of these steps only require snapshots of data to learn a model, and the data can be widely and/or unevenly spaced. Time-derivative information is not needed. We apply this framework to the Kuramoto–Sivashinsky equation for domain sizes that exhibit chaotic dynamics with again estimated manifold dimensions ranging from 8 to 28. With this system, we find that dimension reduction improves performance relative to predictions in the ambient space, where artifacts arise. Then, with the low-dimensional model, we vary the training data spacing and find excellent short- and long-time statistical recreation of the true dynamics for widely spaced data (spacing of ∼ 0.7 Lyapunov times). We end by comparing performance with various degrees of dimension reduction and find a "sweet spot" in terms of performance vs dimension. [ABSTRACT FROM AUTHOR]

Repeated maximal exercise separated by 24 hours may be useful in identifying possible objective markers in people with ME/CFS that are not present in healthy controls. We aimed to synthesise studies in which the test-to-retest (24 hours) changes in VO2 and work rate have been compared between people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) and controls. Seven databases (CINAHL, PubMed, PsycINFO, Web of Knowledge, Embase, Scopus and MEDLINE) were searched. Included studies were observational studies that assessed adults over the age of 18 years with a clinical diagnosis of ME/CFS compared to healthy controls. The methodological quality of included studies was assessed using the Systematic Appraisal of Quality for Observational Research critical appraisal framework. Data from included studies were synthesised using a random effects meta-analysis. The pooled mean decrease in peak work rate (five studies), measured at retest, was greater in ME/CFS by −8.55 (95% CI −15.38 to –1.72) W. The pooled mean decrease in work rate at anaerobic threshold (four studies) measured at retest was greater in ME/CFS by −21 (95%CI −38 to −4, tau = 9.8) W. The likelihood that a future study in a similar setting would report a difference in work rate at anaerobic threshold which would exceed a minimal clinically important difference (10 W) is 78% (95% CI 40%–91%). Synthesised data indicate that people with ME/CFS demonstrate a clinically significant test–retest reduction in work rate at the anaerobic threshold when compared to apparently healthy controls. [ABSTRACT FROM AUTHOR]

Background: Fundamental movement skill (FMS) competence is associated with physical activity during childhood, with higher FMS competence associated with higher physical activity levels; however, the effectiveness of FMS interventions in primary school-aged children is not fully understood. Objective: The purpose of this study was to evaluate the effectiveness of FMS interventions at improving daily levels of moderate to vigorous physical activity (MVPA) in 5- to 11-year-old children. Methods: Systematic searches were completed in eight electronic databases (MEDLINE, CINAHL, PubMed, Web of Science, SPORTDiscus, EMBASE, ERIC and Scopus). Studies were included if they were randomised or non-randomised controlled trials that implemented a physical activity intervention with an FMS component in 5- to 11-year-old children and included objectively measured daily levels of MVPA. Methodological quality was assessed using the Cochrane risk of bias tools for randomised and non-randomised controlled trials. Random effects meta-analysis was performed to determine the pooled intervention effect (mean difference) on minutes spent in MVPA with meta-regression for the use of an operationalised definition of FMS, in line with the criteria reported by Logan et al. Results: A total of 19 studies were identified for review and 14 studies were eligible for meta-analysis. The pooled intervention effect was 4.3 min (95% confidence interval [CI] − 0.03 to 8.8) of MVPA per day. The percentage of future studies likely to find an effect greater than the minimal clinically important difference was 47% (95% CI 22–70). Studies that attempted to conceptualise and define FMS by combining at least one of Logan and colleagues' operational definitions with a measure of FMS had a positive effect on daily MVPA (13.3 min/day, 95% CI 8.0–18.6; R2 = 0.89). Meta-regression for the three levels of criteria reported by Logan et al. showed a linear increase in MVPA, with studies using all three criteria experiencing the largest additive effect (15.7 min/day, 95% CI 8.9–22.6; R2 = 0.89). Conclusions: FMS interventions have the potential to increase daily levels of MVPA in 5- to 11-year-old children. However, future studies should concentrate on establishing an accurate conceptualisation of FMS and how FMS will be integrated within their intervention to further increase physical activity levels. Trial Registration: Prospero registration number: CRD42017058718. [ABSTRACT FROM AUTHOR]

Using Brofenbrenner's socio-ecological model as a conceptual framework, the objective of this study was to determine playground users (primary school staff and pupils) perceptions of the barriers and facilitators to a physically active school playground at an intra-personal (individual), inter-personal (social), environmental and policy level. Results from a series of qualitative interactions with children (n = 65) from years five and six (9 to 11 years old), and structured interviews with adult teachers (n = 11) revealed key differences in the child and adult perceptions of the playground and the purpose of break-times. A number of inter-related environmental boundaries and school policies were identified as restrictive to children's explorations and activity levels during 'free play' periods, which centred on resource availability, accessibility and health and safety. Further, traditional playground hierarchies act to promote and prevent physical activity engagement for different groups (e.g. gender and age). Finally, differences between the adult and child perception of the primary school playground were observed. Playground physical activity, during break-times appears to be affected by a number of variables at each level of the socio-ecological model. This study provides an opportunity for primary schools to reflect on primary school playground strategies and practices that are implemented at each level of the socio-ecological model to encourage a more effective use of the playground during school break-times. [ABSTRACT FROM AUTHOR]

The school playground can promote PA for large numbers of children. This study identifies areas of the playground that children visited at break-times, the decisions according to gender and the influence of contextual and environmental variables on PA levels. The playground of a culturally diverse primary school was observed during morning break-times and lunchtimes. Counts of sedentary, LPA, and MVPA episodes, and the contexts in which they occurred were recorded using the system for observing play and leisure in youth (SOPLAY). Ball sports areas had higher counts of boys (mean ± SD; 9.9 ± 4.8) compared to girls (2.0 ± 3.5); areas promoting climbing and social interaction had higher counts of girls (7.9 ± 7.2) compared to boys (3.5 ± 2.9). The proportion of MVPA episodes during break-times was 34% ± 26%. Areas of the playground with organised activities had 2.70 (95%CI: 1.87 to 3.91) times higher MVPA counts than areas "not organised". Areas with "supervision" were associated with higher MVPA counts (1.34; 1.18 to 1.53) compared with "not supervised" areas. Organisation and supervision might influence PA choices and PA levels of children in the primary school playground. Further investigation is required to explore different playgrounds settings, and context and gender preferences. [ABSTRACT FROM AUTHOR]

Many materials, processes, and structures in science and engineering have important features at multiple scales of time and/or space; examples include biological tissues, active matter, oceans, networks, and images. Explicitly extracting, describing, and defining such features are difficult tasks, at least in part because each system has a unique set of features. Here, we introduce an analysis method that, given a set of observations, discovers an energetic hierarchy of structures localized in scale and space. We call the resulting basis vectors a "data-driven wavelet decomposition." We show that this decomposition reflects the inherent structure of the dataset it acts on, whether it has no structure, structure dominated by a single scale, or structure on a hierarchy of scales. In particular, when applied to turbulence--a highdimensional, nonlinear, multiscale process--the method reveals self-similar structure over a wide range of spatial scales, providing direct, model-free evidence for a century-old phenomenological picture of turbulence. This approach is a starting point for the characterization of localized hierarchical structures in multiscale systems, which we may think of as the building blocks of these systems. [ABSTRACT FROM AUTHOR]

Wall-bounded turbulence exhibits patterns that persist in time and space: coherent structures. These are important for transport processes and form a conceptual framework for important theoretical approaches. Key observed structures include quasi-streamwise and hairpin vortices, as well as the localized spots and puffs of turbulence observed during transition. This review describes recent research on so-called exact coherent states (ECS) in wall-bounded parallel flows at Reynolds numbers Re 104; these are nonturbulent, nonlinear solutions to the Navier–Stokes equations that in many cases resemble coherent structures in turbulence. That is, idealized versions of many of these structures exist as distinct, self-sustaining entities. ECS are saddle points in state space and form, at least in part, the state space skeleton of the turbulent dynamics. While most work on ECS focuses on Newtonian flow, some advances have been made on the role of ECS in turbulent drag reduction in polymer solutions. Emerging directions include applications to control and connections to large-scale structures and the attached eddy model. [ABSTRACT FROM AUTHOR]

The article discusses the lesson plan for the college course "Hunting Witches in Early Modern Europe," from a roundtable panel on experiential learning in history teaching, held October 22, 2015, at the 16th Century Society & Conference annual meeting.

In this work, we numerically investigate flow instabilities of inertialess circular Couette flow of dilute wormlike micelle solutions. Using the reformulated reactive rod model (RRM-R) (Hommel and Graham, 2021), which treats micelles as rigid Brownian rods undergoing reversible scission and fusion in flow, we study the development and behavior of both vorticity banding and finger-like instabilities. In particular, we focus on solutions that exhibit reentrant constitutive curves, in which there exists some region where the shear stress, τ , has a multivalued relation to shear rate, γ ̇. We find that the radial dependence of the shear stress in circular Couette flow allows for solutions in which parts of the domain lie in the region of the flow curve where ∂ τ / ∂ γ ̇ > 0 , while others lie in the region where ∂ τ / ∂ γ ̇ < 0 ; this mixed behavior can lead to complex flow instabilities that manifest as finger-like structures of elongated and anisotropically-oriented micelles. In 3D simulations we find that the initial instability is 2D in origin, and 3D finger-like structures arise through the axial instability of 2D sheets. Finally, we show that the RRM-R can capture vorticity banding in narrow-gap circular Couette flow and that vorticity bands are linearly stable to perturbations. • Dilute wormlike micelle solutions are modeled with the reactive rod model. • Observed finger-like and vorticity banding instabilities in circular Couette flow. • 'Fingers' develop for flow with a negative shear stress vs. shear rate slope. • Finger-like instability is 2D, structures are unstable to 3D disturbances. • Vorticity bands are linearly stable and develop in reentrant flow curve regions. [ABSTRACT FROM AUTHOR]

A two-fluid continuum model is developed to describe mass transport in electro- and magnetorheological suspensions. The particle flux is related to the field-induced and hydrodynamic stresses. Solutions of the resulting mass balance show column formation in the absence of flow and stripe formation when a suspension is subjected simultaneously to an applied electric field and shear flow. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

When a chemical reaction is carried out on a catalytic ribbon, the spatial average temperature of which is kept constant by electrical heating, spatiotemporal temperature patterns form when the uniform steady state is unstable at the set temperature. Numerical simulations reveal periodic and aperiodic patterns of moving pulses, ‘‘breathing’’ pulses, or stationary and oscillatory fronts. The transitions between some of these patterns are intricate and proceed via global bifurcations. Bifurcation maps of parameter regions leading to specific patterns are used to gain insight into pattern formation and organization of these parameter regions. The relations among the dynamics of the uncontrolled system, the ribbon length, and the selected pattern are discussed. Similar patterns are expected to evolve in other reaction–diffusion systems subject to control of space-averaged properties. [ABSTRACT FROM AUTHOR]

Data-driven approximations of the Koopman operator are promising for predicting the time evolution of systems characterized by complex dynamics. Among these methods, the approach known as extended dynamic mode decomposition with dictionary learning (EDMD-DL) has garnered significant attention. Here, we present a modification of EDMD-DL that concurrently determines both the dictionary of observables and the corresponding approximation of the Koopman operator. This innovation leverages automatic differentiation to facilitate gradient descent computations through the pseudoinverse. We also address the performance of several alternative methodologies. We assess a "pure" Koopman approach, which involves the direct time-integration of a linear, high-dimensional system governing the dynamics within the space of observables. Additionally, we explore a modified approach where the system alternates between spaces of states and observables at each time step—this approach no longer satisfies the linearity of the true Koopman operator representation. For further comparisons, we also apply a state-space approach (neural ordinary differential equations). We consider systems encompassing two- and three-dimensional ordinary differential equation systems featuring steady, oscillatory, and chaotic attractors, as well as partial differential equations exhibiting increasingly complex and intricate behaviors. Our framework significantly outperforms EDMD-DL. Furthermore, the state-space approach offers superior performance compared to the "pure" Koopman approach where the entire time evolution occurs in the space of observables. When the temporal evolution of the Koopman approach alternates between states and observables at each time step, however, its predictions become comparable to those of the state-space approach. [ABSTRACT FROM AUTHOR]

The presence of a tiny amount of polymers (a few parts per million) in a fluid dramatically reduces turbulent drag. For this reason, polymer additives have been proposed to be used in flood remediation: in an open channel at a fixed flow rate, the decrease in friction due to polymer addition is expected to lead to a decrease in water height in the channel. However, in a recent field experiment, a counterintuitive transient increase in water height has been observed downstream of polymer injection, with the amplitude and duration of the height increases being the largest far downstream of the injection point. We numerically investigate the effect of polymer additives on the water height in a long channel using the shallow water equations augmented with an evolution equation for polymer concentration that incorporates turbulent dispersion and polymer degradation, as well as a friction coefficient that decreases with increasing polymer concentration. The model predicts the existence of a region originating at the polymer injection point and propagating downstream at the fluid velocity in which the height overshoots before decreasing. This region spreads and grows in amplitude with a downstream position, consistent with experimental observations. We elucidate the mechanism of this unexpected rise in water height in the channel and illustrate it with a simple model. The reduction in friction due to polymer injection leads to fluid acceleration. Therefore, the fast-moving fluid upstream runs into slow-moving fluid downstream, leading to the transient "piling up" of the fluid just downstream of the region of polymer-laden fluid, and hence to the emergence of the height overshoot. We also suggest a technique to mitigate the water rise, as this is detrimental to practical applications. • Polymer additives may aid in mitigating flooding by increasing drainage capacity. • Polymer injection in an open channel exhibits a transient water height overshoot. • Modified shallow water equations capture all the aspects of water height dynamics. • The interplay between fluid inertia and drag reduction induces height overshoot. • Along with the mechanism of overshoot, we describe techniques to mitigate it. [ABSTRACT FROM AUTHOR]

We present a tensor constitutive model for predicting stress and flow-induced structure formation in dilute wormlike micellar solutions. The micellar solution is treated as a dilute suspension of rigid Brownian rods whose length varies dynamically. Consistent with the mechanism presented by Turner and Cates [J. Phys.: Condens. Matter 4, 3719 (1992)], flow-induced alignment of the rods is assumed to promote increase of rod length that corresponds to the formation of flow-induced structures observed in experiments. At very high deformation rate, hydrodynamic stresses causes the rod length to decrease. These mechanisms are implemented in a phenomenological equation governing the evolution of rod length, with the number density of rods appropriately modified to ensure conservation of surfactant mass. The model leads first to an increase in both shear and extensional viscosity as deformation rate increases and then to a decrease at higher rates. If the rate constant for flow-induced rod growth is sufficiently large, the model predicts a multivalued relation between stress and deformation rate in both shear and uniaxial extension. Predictions for shear and extensional flow at steady state are in reasonable agreement with experimental results. By design, the model is simple enough to serve as a tractable constitutive relation for computational fluid dynamics studies. [ABSTRACT FROM AUTHOR]

Killer cell immunoglobulin-like receptors (KIRs) modulate disease progression of pathogens including HIV, malaria, and hepatitis C. Cynomolgus and rhesus macaques are widely used as nonhuman primate models to study human pathogens, and so, considerable effort has been put into characterizing their KIR genetics. However, previous studies have relied on cDNA cloning and Sanger sequencing that lack the throughput of current sequencing platforms. In this study, we present a high throughput, full-length allele discovery method utilizing Pacific Biosciences circular consensus sequencing (CCS). We also describe a new approach to Macaque Exome Sequencing (MES) and the development of the Rhexome1.0, an adapted target capture reagent that includes macaque-specific capture probe sets. By using sequence reads generated by whole genome sequencing (WGS) and MES to inform primer design, we were able to increase the sensitivity of KIR allele discovery. We demonstrate this increased sensitivity by defining nine novel alleles within a cohort of Mauritian cynomolgus macaques (MCM), a geographically isolated population with restricted KIR genetics that was thought to be completely characterized. Finally, we describe an approach to genotyping KIRs directly from sequence reads generated using WGS/MES reads. The findings presented here expand our understanding of KIR genetics in MCM by associating new genes with all eight KIR haplotypes and demonstrating the existence of at least one KIR3DS gene associated with every haplotype. [ABSTRACT FROM AUTHOR]

Predator-prey interactions may be strongly influenced by temperature variations in marine ecosystems. Consequently, climate change may alter the importance of predators with repercussions for ecosystem functioning and structure., In North-eastern Pacific kelp forests, the starfish Pycnopodia helianthoides is known to be an important predator of the purple sea urchin Strongylocentrotus purpuratus. Here we investigated the influence of water temperature on this predator-prey interaction by: (i) assessing the spatial distribution and temporal dynamics of both species across a temperature gradient in the northern Channel Islands, California, and (ii) investigating how the feeding rate of P. helianthoides on S. purpuratus is affected by temperature in laboratory tests., On average, at sites where mean annual temperatures were <14 °C, P. helianthoides were common, S. purpuratus was rare and kelp was persistent, whereas where mean annual temperatures exceeded 14 °C, P. helianthoides and kelp were rare and S. purpuratus abundant. Temperature was found to be the primary environmental factor influencing P. helianthoides abundance, and in turn P. helianthoides was the primary determinant of S. purpuratus abundance. In the laboratory, temperatures >16 °C (equivalent to summer temperatures at sites where P. helianthoides were rare) reduced predation rates regardless of predator and prey sizes, although larger sea urchins were consumed only by large starfishes., These results clearly demonstrate that the effect of P. helianthoides on S. purpuratus is strongly mediated by temperature, and that the local abundance and predation rate of P. helianthoides on sea urchins will likely decrease with future warming. A reduction in top-down control on sea urchins, combined with other expected impacts of climate change on kelp, poses significant risks for the persistence of kelp forests in the future. [ABSTRACT FROM AUTHOR]

Very little is currently known about the major histocompatibility complex (MHC) region of cynomolgus macaques ( Macaca fascicularis; Mafa) from Chinese breeding centers. We performed comprehensive MHC class I haplotype analysis of 100 cynomolgus macaques from two different centers, with animals from different reported original geographic origins (Vietnamese, Cambodian, and Cambodian/Indonesian mixed-origin). Many of the samples were of known relation to each other (sire, dam, and progeny sets), making it possible to characterize lineage-level haplotypes in these animals. We identified 52 Mafa-A and 74 Mafa-B haplotypes in this cohort, many of which were restricted to specific sample origins. We also characterized full-length MHC class I transcripts using Pacific Biosciences (PacBio) RS II single-molecule real-time (SMRT) sequencing. This technology allows for complete read-through of unfragmented MHC class I transcripts (~1100 bp in length), so no assembly is required to unambiguously resolve novel full-length sequences. Overall, we identified 311 total full-length transcripts in a subset of 72 cynomolgus macaques from these Chinese breeding facilities; 130 of these sequences were novel and an additional 115 extended existing short database sequences to span the complete open reading frame. This significantly expands the number of Mafa-A, Mafa-B, and Mafa-I full-length alleles in the official cynomolgus macaque MHC class I database. The PacBio technique described here represents a general method for full-length allele discovery and genotyping that can be extended to other complex immune loci such as MHC class II, killer immunoglobulin-like receptors, and Fc gamma receptors. [ABSTRACT FROM AUTHOR]

The realization of quantum information processing would disrupt the status quo in the realm of computation; the extraordinary power of a hypothetical quantum computer motivates significant research efforts toward creating such a device. One promising route to enable quantum information processing involves employing electronic spins as the elementary unit of information, known as a qubit. Within this paradigm, paramagnetic defect sites in solid-state materials demonstrate appreciable promise, and recent developments in paramagnetic molecular coordination complexes illustrate an encouraging trajectory. While solid-state systems exhibit long spin coherence lifetimes, rational control of their properties remains challenging. Effecting synthetic control over qubit design prompted the study of tunable molecular species to develop design principles for spin coherence lifetimes. The challenge now lies in extending those molecular design principles to target new solid-state architectures that could enable device-scale systems. In this perspective, we detail recent progress in the rational design of molecular qubit complexes and highlight the advances that will be necessary in order to apply that progress to solid-state systems. We further examine the impact that the lessons learned from the study of qubits can have in the related fields of magnetic resonance imaging and biological sensing. [ABSTRACT FROM AUTHOR]

Nuclear-electronic interactions are a fundamental phenomenon which impacts fields from magnetic resonance imaging to quantum information processing (QIP). The realization of QIP would transform diverse areas of research including accurate simulation of quantum dynamics and cryptography. One promising candidate for the smallest unit of QIP, a qubit, is electronic spin. Electronic spins in molecules offer significant advantages with regard to QIP, and for the emerging field of quantum sensing. Yet relative to other qubit candidates, they possess shorter superposition lifetimes, known as coherence times or T2, due to interactions with nuclear spins in the local environment. Designing complexes with sufficiently long values of T2 requires an understanding of precisely how the position of nuclear spins relative to the electronic spin center affects decoherence. Herein, we report the first synthetic study of the relationship between nuclear spin-electron spin distance and decoherence. Through the synthesis of four vanadyl complexes, (Ph4P)2[VO(C3H6S2)2] (1), (Ph4P)2[VO(C5H6S4)2] (2), (Ph4P)2[VO(C7H6S6)2] (3), and (Ph4P)2[VO(C9H6S8)2] (4), we are able to synthetically place a spin-laden propyl moiety at well-defined distances from an electronic spin center by employing a spin-free carbon-sulfur scaffold. We interrogate this series of molecules with pulsed electron paramagnetic resonance (EPR) spectroscopy to determine their coherence times. Our studies demonstrate a sharp jump in T2 when the average V-H distance is decreased from 6.6(6) to 4.0(4) Å, indicating that spin-active nuclei sufficiently close to the electronic spin center do not contribute to decoherence. These results illustrate the power of synthetic chemistry in elucidating the fundamental mechanisms underlying electronic polarization transfer and provide vital principles for the rational design of long-coherence electronic qubits. [ABSTRACT FROM AUTHOR]

A counterintuitive three-order of magnitude slowing of the spin–lattice relaxation rate is observed in a high spin qubit at high magnetic field via multifrequency pulsed electron paramagnetic resonance measurements. [ABSTRACT FROM AUTHOR]

Two experimental treatments are used to study the effects of auction risk across five mechanisms. The first canonical, baseline treatment features only strategic risk and replicates the standard results that overbidding relative to the risk neutral Nash equilibrium is prevalent in all common auction mechanisms except for the English auction. We do not find evidence that bidders' measured risk preferences can explain these patterns of overbidding. To enhance salience, we introduce a second novel treatment with external risk. This treatment captures the risk, prevalent in online auctions, that winners will not receive a good of value. We find that dynamic auctions--including the English--are particularly susceptible to overbidding in this environment. We note that overbidding is somewhat diminished in later periods and that our results may thus have particular relevance for bidders who are not highly experienced or who have not directly experienced losses. We conclude with a brief discussion of research implications. [ABSTRACT FROM AUTHOR]

The article focuses on American Dental Association (ADA) which has been advocating diligently to ensure that tax reform benefits dentists as well as patients and mentions proposal to increase economic development and simplify the tax code. Topics disucssed include how ADA demonstrated to lawmakers the influence of dentists' economic activity, expansion of businesses' ability to immediately expenses and corporations and partnerships with corporate partners.

This work describes simulations of a red blood cell (RBC) in simple shear flow, focusing on the dependence of the cell dynamics on the spontaneous curvature of the membrane. The results show that an oblate spheroidal spontaneous curvature maintains the dimple of the RBC during tank-treading dynamics as well as exhibits off-shear-plane tumbling consistent with the experimental observations of Dupire et al. [J. Dupire, M. Socol, and A. Viallat, Proc. Natl. Acad. Sei. USA 109, 20808 (2012)] and their hypothesis of an inhomogeneous spontaneous shape. As the flow strength (capillary number Ca) is increased at a particular viscosity ratio between inner and outer fluid, the dynamics undergo transitions in the following sequence: tumbling, kayaking or rolling, tilted tank-treading, oscillating-swinging, swinging, and tank-treading. The tilted tank-treading (or spinning frisbee) regime has been previously observed in experiments but not in simulations. Two distinct classes of regime are identified: a membrane reorientation regime, where the part of membrane that is at the dimple at rest moves to the rim and vice versa, is observed in motions at high Ca such as tilted tank-treading, oscillating-swinging, swinging, and tank-treading, and a nonreorientation regime, where the part of the membrane starting from the dimple stays at the dimple, is observed in motions at low Ca such as rolling, tumbling, kayaking, and flip-flopping. [ABSTRACT FROM AUTHOR]

A high percentage of developed drug compounds are poorly soluble in water, which severely limits their applications. Nanotechnology has been used to address this issue. Here we describe a simple and versatile bottom-up approach for the preparation of drug nanostructures by surface solvent evaporation on aluminum surface and polymer-coated surface. Three poorly water soluble drug compounds, including griseofulvin (GF), curcumin and antimalarial compound SL-2-25 have been investigated as model compounds. The structures are mainly characterized by scanning electronic microscopy (SEM) while the GF nanoparticles are also examined by powder X-ray diffraction (PXRD) and thermogravimetric analysis (TGA). A variety of structures including microassemblies composed of nanoparticles, nanospheres and nanofibers have been produced. A sonication method can be employed to produce aqueous nanoparticle suspension. [ABSTRACT FROM AUTHOR]

Addition of a small amount of very large polymer molecules or micelle-forming surfactants to a liquid can dramatically reduce the energy dissipation it exhibits in the turbulent flow regime. This rheological drag reduction phenomenon is widely used, for example, in the Alaska pipeline, but it is not well-understood, and no comparable technology exists to reduce turbulent energy consumption in flows of gases, in which polymers or surfactants cannot be dissolved. The most striking feature of this phenomenon is the existence of a so-called maximum drag reduction (MDR) asymptote: for a given geometry and driving force, there is a maximum level of drag reduction that can be achieved through addition of polymers. Changing the concentration, molecular weight or even the chemical structure of the additives has little to no effect on this asymptotic value. This universality is the major puzzle of drag reduction. We describe direct numerical simulations of turbulent minimal channel flow of Newtonian fluids and viscoelastic polymer solutions. Even in the absence of polymers, we show that there are intervals of "hibernating" turbulence that display very low drag as well as many other features of the MDR asymptote observed in polymer solutions. As Weissenberg number increases to moderate values the frequency of these intervals also increases, and a simple theory captures key features of the intermittent dynamics observed in the simulations. At higher Weissenberg number, these intervals are altered - for example, their duration becomes substantially longer and the instantaneous Reynolds shear stress during them becomes very small. Additionally, simulations of "edge states," dynamical trajectories that lie on the boundary between turbulent and laminar flow, display characteristics that are similar to those of hibernating turbulence and thus to the MDR asymptote, again even in the absence of polymer additives. Based on these observations, we propose a tentative unified description of rheological drag reduction. The existence of MDR-like intervals even in the absence of additives sheds light on the observed universality of MDR and may ultimately lead to new flow control approaches for improving energy efficiency in a wide range of processes. [ABSTRACT FROM AUTHOR]

Enabling the rational synthesis of molecular candidates for quantum information processing requires design principles that minimize electron spin decoherence. Here we report a systematic investigation of decoherence via the synthesis of two series of paramagnetic coordination complexes. These complexes, [M(C2O4)3]3- (M = Ru, Cr, Fe) and [M(CN)6]3- (M = Fe, Ru, Os), were prepared and interrogated by pulsed electron paramagnetic resonance (EPR) spectroscopy to assess quantitatively the influence of the magnitude of spin (S = ½, 3/2, 5/2) and spin-orbit coupling (ζ = 464, 880, 3100 cm-1) on quantum decoherence. Coherence times (T2) were collected via Hahn echo experiments and revealed a small dependence on the two variables studied, demonstrating that the magnitudes of spin and spin-orbit coupling are not the primary drivers of electron spin decoherence. On the basis of these conclusions, a proof-of-concept molecule, [Ru(C2O4)3]3-, was selected for further study. The two parameters establishing the viability of a qubit are a long coherence time, T2, and the presence of Rabi oscillations. The complex [Ru(C2O4)3]3- exhibits both a coherence time of T2 = 3.4 μs and the rarely observed Rabi oscillations. These two features establish [Ru(C2O4)3]3- as a molecular qubit candidate and mark the viability of coordination complexes as qubit platforms. Our results illustrate that the design of qubit candidates can be achieved with a wide range of paramagnetic ions and spin states while preserving a long-lived coherence. [ABSTRACT FROM AUTHOR]

With the development of multidetector computed-tomography (MDCT) scanners and ultrathin bronchoscopes, the use of bronchoscopy for diagnosing peripheral lung-cancer nodules is becoming a viable option. The work flow for assessing lung cancer consists of two phases: 1) 3-D MDCT analysis and 2) live bronchoscopy. Unfortunately, the yield rates for peripheral bronchoscopy have been reported to be as low as 14%, and bronchoscopy performance varies considerably between physicians. Recently, proposed image-guided systems have shown promise for assisting with peripheral bronchoscopy. Yet, MDCT-based route planning to target sites has relied on tedious error-prone techniques. In addition, route planning tends not to incorporate known anatomical, device, and procedural constraints that impact a feasible route. Finally, existing systems do not effectively integrate MDCT-derived route information into the live guidance process. We propose a system that incorporates an automatic optimal route-planning method, which integrates known route constraints. Furthermore, our system offers a natural translation of the MDCT-based route plan into the live guidance strategy via MDCT/video data fusion. An image-based study demonstrates the route-planning method’s functionality. Next, we present a prospective lung-cancer patient study in which our system achieved a successful navigation rate of 91% to target sites. Furthermore, when compared to a competing commercial system, our system enabled bronchoscopy over two airways deeper into the airway-tree periphery with a sample time that was nearly 2 min shorter on average. Finally, our system’s ability to almost perfectly predict the depth of a bronchoscope’s navigable route in advance represents a substantial benefit of optimal route planning. [ABSTRACT FROM PUBLISHER]

Abstract: In three experiments we examine the extent to which strategic sophistication (i.e., inductive reasoning, iterative dominance and level-k thinking) is determined by broader cognitive skills. In the first experiment we replicate previous results showing strong associations between cognitive ability and sophistication in a game of iterative dominance and show that similar results arise in a game requiring induction. In the second two experiments we extend the literature in new directions. In Experiment 2 we modify the games to better capture participantsʼ ability to reason inductively and predict the sophistication of others and, again, find strong associations between cognitive ability, measured using a common IQ test, and sophistication. In Experiment 3 we examine more closely the causal nature of the relationship between cognitive ability and sophistication. We use a standard tool from cognitive psychology to randomly shock the cognitive ability of participants and show that this significantly affects game performance. [Copyright &y& Elsevier]

We utilize wavelet coherency methodology with simulated confidence bounds to examine the short-term and long-term dependencies of the returns for S&P 500 and the S&P GSCI®commodity index. Our results indicate no evidence of co-movement between S&P 500 total return and the S&P GSCI®commodity index total return in the short term, thereby suggesting diversification gains for equity investors. Importantly, this finding encompasses the onset of the current financial crisis. However, long-term diversification benefits, particularly after the onset of the recent financial crisis, are limited. We find, moreover, no consistent evidence of co-movements between S&P 500 and 10 individual sub-indexes of the S&P GSCI®commodity index. Of particular importance, we report weak co-movement of returns between S&P 500 and S&P GSCI®Precious Metals total return and S&P 500 and S&P GSCI®Softs at all frequencies, implying significant diversification gains both for short-term and long-term investors. [ABSTRACT FROM AUTHOR]