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Little is known about current practices in high-value care (HVC) bedside teaching. A lack of instruments for measuring bedside HVC behaviors confounds efforts to assess the impact of curricular interventions. The authors aimed to define observable HVC concepts by developing an instrument to measure the content and frequency of HVC discussions. The authors developed the HVC Rounding Tool in four iterative phases, using Messick’s validity framework. Phases 1 and 2 were designed to collect evidence of content validity, Phases 3 and 4 to collect evidence of response process and internal structure. Phase 1 identified HVC topics within the literature. Phase 2 used a modified Delphi approach for construct definition and tool development. Through two rounds, the Delphi panel narrowed 16 HVC topics to 11 observable items, categorized into three domains (quality, cost, and patient values). Phase 3 involved rater training and creation of a codebook. Phase 4 involved three iterations of instrument piloting. Six trained raters, in pairs, observed bedside rounds during 148 patient encounters in 2016. Weighted kappas for each domain demonstrated improvement from the first to third iteration: Quality increased from 0.65 (95% CI 0.55–0.79) to 1.00, cost from 0.58 (95% CI 0.4–0.75) to 0.96 (95% CI 0.80–1.00), and patient values from 0.41 (95% CI 0.19–0.68) to 1.00. Percent positive agreement for all domains improved from 65.3% to 98.1%. This tool, the first with established validity evidence, addresses an important educational gap for measuring the translation of HVC from theoretical knowledge to bedside practice.

Histone deacetylase 4 (Hdac4) is known to control chondrocyte hypertrophy and bone formation. We have previously shown that parathyroid hormone (PTH) regulates many aspects of Hdac4 function in osteoblastic cells in vitro; however, in vivo confirmation was previously precluded by pre-weaning lethality of the Hdac4 deficient mice. To analyze the function of Hdac4 in bone in mature animals, we generated mice with osteoblast lineage-specific knockout of Hdac4 (Hdac4(ob−/−)) by crossing transgenic mice expressing Cre recombinase under the control of a 2.3kb fragment of the Col1a1 promoter with mice bearing loxP-Hdac4. The Hdac4(ob−/−) mice survive to adulthood and developed a mild skeletal phenotype. At 12 weeks of age, they had short, irregularly-shaped and stiff tails due to smaller tail vertebrae, with almost no growth plates. The tibial growth plate zone was also thinned and Mmp13 and Sost mRNAs were increased in the distal femurs of Hdac4(ob−/−) mice. Immunohistochemistry showed that sclerostin was elevated in Hdac4(ob−/−) mice, suggesting that Hdac4 inhibits its gene and protein expression. To determine the effect of PTH in these mice, hPTH (1–34) or saline were delivered for 14 days with subcutaneously implanted devices in 8-week-old female Hdac4(ob−/−) and wild type (Hdac4(fl/fl)) mice. Serum CTX, a marker of bone resorption, was increased in Hdac4(ob−/−) mice with or without PTH treatment. Tibial cortical BV/TV, Ct.Th, and relative cortical area (RCA) were decreased in Hdac4(ob−/−) mice but PTH caused no further decrease in Hdac4(ob−/−) mice. Tibial trabecular BV/TV and thickness were not changed significantly in Hdac4(ob−/−) mice but decreased with PTH treatment. These results indicate that Hdac4 inhibits bone resorption and has anabolic effects via inhibiting Mmp13 and Sost/sclerostin expression. Hdac4 influences cortical bone mass and thickness and knockout of Hdac4 prevents the catabolic effect of PTH in cortical bone.

It is generally assumed that low-coordinated sites at extended defects of oxide surfaces like steps or edges are more reactive than the regular, fully coordinated sites at the flat terraces. In this work we have considered the properties of stepped surfaces of anatase TiO2 and tetragonal ZrO2 by means of periodic DFT+U calculations. For both oxides, the stability of oxygen vacancies located near the step edges is compared to that of the same defects at the regular terraces. The capability of the steps to induce nucleation of metal nanoparticles on the surface has been evaluated by simulating the adsorption of a single ruthenium adatom. We conclude that, for anatase, step edges have no particular role in favouring the reduction of the oxide by reducing the cost for oxygen abstraction; in the same way, there is no special role of the stepped anatase surface in stabilizing adsorbed Ru atoms. On the contrary, step edges on zirconia display some capability to stabilise oxygen vacancies and ruthenium adatoms.

Dehydroxylated, hydroxylated and hydrated anatase TiO2 samples have been exposed to acetylene at room temperature. The interaction leads to the formation of polycyclic aromatic hydrocarbons (PAHs) and is accompanied by the appearance of Ti3+ ions, as shown by electron paramagnetic resonance (EPR) spectra. Fully or partly dehydroxylated samples show higher reactivity, whereas the hydrated samples are chemically inert. The experimental results point towards a crucial role of the more reactive (001) facets of anatase nanoparticles. Density functional theory calculations show that acetylene physisorbs on the anatase (101) surface without activation of the C-H bond. The reduced (101) surface (O vacancies) leads to acetylene activation but not to dissociative adsorption. In contrast, the dehydroxylated (001) anatase surface is very active and leads to the spontaneous splitting of the C-H bond with formation of Ti-C2H and OH groups. This is followed by subsequent additions of C2H2 molecules with formation of PAHs. During the dissociation of C2H2, radical species do not form and electrons are not transferred to the surface because direct Ti-C covalent bonds form on the surface. However, the ring closure in the formation of the aromatic compounds leaves behind hydrogen atoms that donate their valence electrons to the oxide. This results in the appearance of EPR-active Ti3+ centres. On the surface of things: Acetylene oligomerisation occurs on the surface of anatase TiO2 leading to the formation of polycyclic aromatic hydrocarbons and a reduced titania surface. The mechanism of the reaction has been elucidated by EPR measurements and DFT calculations (see figure).

The mechanism of imine reduction by formic acid with a single-site iridicycle catalyst has been investigated by density functional theory (DFT), NMR spectroscopy, and kinetic measurements. The NMR and kinetic studies suggest that the transfer hydrogenation is turnover-limited by the hydride formation step. The calculations reveal that, amongst a number of possibilities, hydride formation from the iridicycle and formate probably proceeds by an ion-pair mechanism, whereas the hydride transfer to the imino bond occurs in an outer-sphere manner. In the gas phase, in the most favourable pathway, the activation energies in the hydride formation and transfer steps are 26-28 and 7-8 kcal mol(-1) , respectively. Introducing one explicit methanol molecule into the modelling alters the energy barrier significantly, reducing the energies to around 18 and 2 kcal mol(-1) for the two steps, respectively. The DFT investigation further shows that methanol participates in the transition state of the turnover-limiting hydride formation step by hydrogen-bonding to the formate anion and thereby stabilising the ion pair.

The scope of this work is to study at atomistic level the mechanism of hydrogen spillover promoted by metal particles on oxide surfaces. By means of Density Functional Theory calculations with Hubbard correction (DFT+U) we have analyzed the adsorption and dissociation of molecular hydrogen on anatase titania, a-TiO2 (101), and tetragonal zirconia, t-ZrO2 (101), surfaces in the presence of a supported Ru10 nanocluster. The role of the supported metal particle is essential as it favors the spontaneous dissociation of H2, a process which does not occur on the bare oxide surface. At low hydrogen coverage, the H atoms prefer to stay on the Ru10 particle, charge accumulates on the metal cluster, and reduction of the oxide does not take place. On a hydroxylated surface, the presence of a Ru nanoparticle is expected to promote the reverse effect, i.e. hydrogen reverse spillover from the oxide to the supported metal. It is only at high hydrogen coverage, resulting in the adsorption of several H2 molecules on the metal cluster, that it becomes thermodynamically favorable to have hydrogen transfer from the metal to the O sites of the oxide surface. In both TiO2 and ZrO2 surfaces the migration of an H atom from the Ru cluster to the surface is accompanied by an electron transfer to the empty states of the support with reduction of the oxide surface.

During the last 20 years, using scanning tunneling microscopy (STM) and atomic force microscopy, scientists have successfully achieved vertical and lateral repositioning of individual atoms on and in different types of surfaces. Such atom manipulation allows the bottom-up assembly of novel nanostructures that can otherwise not be fabricated. It is therefore surprising that controlled repositioning of virtual atoms, i.e., atomic vacancies, across atomic lattices has not yet been achieved experimentally. Here we use STM at liquid helium temperature (4.5 K) to create individual Cl vacancies and subsequently to laterally manipulate them across the surface of ultrathin sodium chloride films. This allows monitoring the interactions between two neighboring vacancies with different separations. Our findings are corroborated by density functional theory calculations and STM image simulations. The lateral manipulation of atomic vacancies opens up a new playground for the investigation of fundamental physical properties of vacancy nanostructures of any size and shape and their coupling with the supporting substrate, and of the interaction of various deposits with charged vacancies.

Acceptance sampling is a useful tool for determining whether submitted lots should be accepted or rejected. With the current increase in outsourcing production processes and the high-quality levels required, it is very desirable to have an efficient and economic sampling scheme. This paper develops a variables repetitive group sampling (RGS) plan that accounts for the process yield (meeting the manufacturing specifications) and the quality loss (variation from the target). The plan parameters are determined by solving a nonlinear optimisation problem. This implies that the plan parameters minimise the average sample number required for inspection and fulfil the classical two-point conditions on the operating characteristic (OC) curve. Besides, this paper investigates the efficiency of the proposed plan and compares it with the existing variables single sampling plan. Tables of the plan parameters for the proposed variables RGS plan are provided and an application example is presented for illustration.

Trifluoromethylation via broken C-F bonds Trifluoromethyl substituents are widely used in pharmaceutical research to tune the properties of drug candidates. Generally, they are introduced intact through the formation of carbon-carbon bonds. Levin et al. discovered an unusual alternative mechanism, in which borane abstracts fluoride from the CF 3 group in a gold complex. The activated CF 2 fragment can then bond to a wide variety of other carbon substituents added to the same gold center. Return of the fluoride liberates a trifluoromethylated compound from the metal. This mechanism could be useful for the introduction of radioactive fluoride substituents for positron emission tomography applications. Science , this issue p. 1272

The mechanisms and selectivities of the cycloadditions of tropone to dimethylfulvene have been investigated with M06-2X and B3LYP-D3 density functional theory (DFT) calculations and quasi-classical direct molecular dynamics simulations. The originally proposed reaction mechanism (Houk) involves a highly peri-, regio-, and stereoselective [6F + 4T] cycloaddition of tropone [4π] to dimethylfulvene [6π], followed by a [1,5] hydrogen shift, and, finally, a second [6 + 4] cycloaddition of tropone [6π] to the cyclopentadiene moiety [4π]. Paddon-Row and Warrener proposed an alternative mechanism: the initial cycloaddition involves a different [6T + 4F] cycloaddition in which fulvene acts as the 4π component, and a subsequent Cope rearrangement produces the formal [6F + 4T] adduct. Computations now demonstrate that the initial cycloaddition proceeds via an ambimodal transition state that can lead to both of the proposed [6 + 4] adducts. These adducts can interconvert through a [3,3] sigmatropic shift (Cope rearra...

A ternary metallic CuPdPt nanocatalyst (NC) is synthesized using a wet chemical reduction method, which is sequentially designed, in the presence of acid treated carbon nanotubes. This NC is a nanocrystal with a configuration of a Cu@Pd core and atomic Pt clusters (∼9 wt%) on the top (Cu@Pd/Pt). A residual current of 92.6%, 5.2 times higher than that of commercial Pt catalysts (at 0.85 V vs. RHE), is retained after 40 000 cycles of an accelerated degradation test (ADT). Atomic and electronic structure analyses show that such exclusive stability mainly results from electron localization at Pt clusters in heterogeneous interfaces of the Cu–Pd core. Most importantly, we develop a robust ternary NC, which shows outstanding MA, superior chemical durability, and ∼90 wt% lower Pt loading than commercial Pt NCs in the oxygen reduction reaction.

Follicular dendritic cell sarcoma is a rare tumor that typically arises within lymph nodes but can also occur extranodally. It is important to have a high index of suspicion, so follicular dendritic cell sarcoma is included in the differential diagnosis of a spindle cell neoplasm in the appropriate clinical and morphologic settings. When included in the differential diagnosis, immunohistochemistry is generally sufficient to substantiate the diagnosis of follicular dendritic cell sarcoma. In this review, we discuss the clinicopathologic features of follicular dendritic cell sarcoma, recent molecular and cytogenetic findings, prognosis, and current approaches to treatment.

Design and test a novel biomaterial for injection laryngoplasty aimed to increase the duration of effectiveness of micronized acellular dermis.Animal model.Injection laryngoplasty was performed in three groups (n = 5) of New Zealand White rabbits. Acellular dermis was either used alone as a control (group 1), was combined with undifferentiated stem cells (group 2), or with predifferentiated chondrocytic cells (group 3). Groups 2 and 3 were supplemented with growth factors. Animals were sacrificed 4 and 12 weeks after laryngoplasty and histologic analysis was completed. The major outcome measure was volume of tissue remaining.After 4 weeks, the mean volume of tissue remaining was 341 ± 89 mmMicronized acellular dermis combined with stem cells and growth factors showed significantly less resorption 12 weeks after injection laryngoplasty compared to micronized acellular dermis alone. Groups using novel tissue-engineered biomaterial showed a lower resorption rate over time compared with acellular dermis alone.NA. Laryngoscope, 128:160-167, 2018.

Mass-selected anionic cobalt clusters of two different sizes (Co2 and Co13) were deposited onto ultrathin NaCl films grown on an Au(111) substrate. Using scanning tunneling microscopy experiments and density functional theory simulations, we show that the deposited Co2 cluster dissociates and that the resulting Co atoms dope the NaCl surface by substituting Na ions. In contrast, the larger Co13 cluster does not dissociate and remains stable on top of the NaCl film. The size-dependent fragmentation of clusters is an important aspect in the understanding of the chemical interaction between size-selected small aggregates of atoms and supporting surfaces. [Figure not available: see fulltext.]

This research develops a heuristic algorithm for assembly line balancing problem (ALBP) of stitching lines in footwear industry. The proposed algorithm can help to design the stitching line with workstations, machines and operators for the production of every new product model. Rank-positional-weighted heuristics and hybrid genetic algorithms are proposed to solve ALBP. First, the heuristics assign tasks and machines to workstations. This solution is then used as an initiative population for hybrid genetic algorithm for further improvement. Real data from footwear manufacturers and experimental designs are used to verify the performance of the proposed algorithm, comparing with one existing bidirectional heuristic. Results indicate that when the size and shape of shoes increase, the proposed genetic algorithm achieves better solution quality than existing heuristics.Production managers can use the research results to quickly design stitching lines for short production cycle time and high labor utilization.

A French prospective randomized trial comparing whole breast radiotherapy with 45 Gy in 25 fractions versus 23 Gy in four fractions demonstrated equivalent 5-year local control and survival. On the basis of this data, we offer the hypofractionated regimen to women who refuse to undergo standard radiotherapy. We report our outcomes and a cost analysis. Between 2000 and 2012, 84 patients participated in this IRB-approved study and underwent whole breast radiation to 23 Gy in four fractions. Local control and survival were analyzed using the Kaplan-Meier method. Acute toxicities and overall long-term cosmetic results were assessed. Costs were estimated from 2012 Medicare reimbursement data and compared to costs from standard courses of 25 and 16 fractions. All 84 patients are included in this report. Median age was 83 (range 42-98). Most patients had stage I (80%), hormone receptor positive (90%) breast cancer. Fifty-eight patients (69%) were treated prone and 26 (31%) supine. At a median follow-up of 3 years, one local recurrence has occurred, of ductal carcinoma in situ histology. Among the 13 patients deceased, two died of metastatic breast cancer. Five-year actuarial local control is 99%, breast cancer-specific survival is 98%, and overall survival is 79%. Toxicities were limited to grade 1 dermatitis in 32 patients (38%) and grade 2 fatigue in three (4%). Sixty-three patients (75%) reported good or excellent cosmetic outcome at their last follow-up. Collected Medicare reimbursement was $4,798 for the hypofractionated course. Compared to the projected reimbursement of standard regimens, $10,372 for 25 fractions and $8,382 for 16 fractions, it resulted in a difference of $5,574 and $3,584, respectively. At a follow-up of 3 years, this hypofractionated regimen appears to be a promising approach, primarily for elderly women who are unable to undergo longer treatment courses but have indications for whole breast radiotherapy.

Systematically and quantitatively determining patterns in consumer flow is an important problem in marketing research. Identifying these patterns can facilitate an understanding of where and when consumers purchase products and services at physical retail shops. Collecting data on real consumers who shop at retail stores is one of the most challenging and expensive aspects of these studies. This article introduces ConvenienceProbe, a phone-based data collection system for retail trade-area analysis. The proposed method targets local residents shopping at neighborhood convenience stores. This study deploys and tests the system by collecting real customer flow data in neighborhood convenience stores. Results show that the consumer flow data collected from the ConvenienceProbe system is comparable to that from a traditional face-to-face interview method.

This study presents several extensions to our previous work on the PipeProbe system, a mobile sensor system for identifying the spatial topology of hidden water pipelines (i.e., non-moldable pipes such as copper and PVC) behind walls or under floors [Lai et al. 2010]. The PipeProbe system works by dropping a tiny wireless sensor capsule into the source of a water pipeline. As the PipeProbe capsule traverses the pipelines, it gathers and transmits pressure and angular velocity readings. Through spatiotemporal analysis of these sensor readings, the proposed algorithm locates all turning points in the pipelines and maps their 3D spatial topology. This study expands upon previous research by developing new sensing techniques that identify variable-diameter pipes and differentiate 90-degree pipe turns from 45-degree pipe bends.

Large indoor spaces continue to pose challenges to independent navigation for people who are blind. Unfortunately, assistive technologies designed to support indoor navigation frequently make errors that are technically difficult or impossible to eliminate. We conducted a study to explore whether there are strategic ways designers can minimize the impact of inevitable errors on user experience. This paper summarizes an online survey of 41 blind individuals regarding their projected acceptance to three types of errors expected of these devices. We found that some errors were more acceptable than others. Factors that impacted results included the error type and the social/environmental setting.

In light of the existing controversy regarding antivenin treatment for copperhead envenomation, a more detailed analysis of the disability from this species is needed.Our objective was to prospectively determine the duration of pain, swelling, and functional disability, i.e., residual venom effects, in patients with copperhead envenomation.Patients with venomous snakebite reported to the North Texas Poison Center between April 2009 and November 2011 were assessed. Patients with confirmed envenomations were contacted by a specialist in poison information. Day zero was the day of the bite and verbal phone consent for study enrollment was obtained at that time. The patient (or their guardian) was contacted by phone daily thereafter, and asked to rate their pain, edema/swelling, and disability using the modified DASH and LEFS scales. Patients were followed to resolution of all symptoms or return to baseline.About 104 cases of venomous snakebite were followed; of which 17 were excluded due to being a dry bites (5) or for having insufficient data during follow-up (11) or due to coagulopathy (1). Overall, residual venom effects from copperhead bites for most patients last between 7 and 13 days. Median time to complete pain resolution was 7 days (mean = 10.7 days). Median length of time to resolution of swelling was 10 days (mean = 13 days) and median length of time to resolution of functional disability was 9 days (mean = 12.2 days).Residual venom effects from copperhead envenomation in this study had a slightly shorter duration than some other studies. Data are skewed due to outliers where residual venom effects lasted for up to 89 days. Initial reoccurrence of some symptoms may be seen. Antivenom (AV) is currently being used for a large percentage of patients with copperhead envenomation. Finally, no differences in duration of venom effects were seen based on age or location of bite.Our study suggests that residual venom effects from copperhead species persist for between 10 and 13 days but may persist for months. Future studies are necessary to identify risk factors for severe/prolonged injury and to define the benefit of AV in patients with copperhead envenomation.

Density functional calculations are employed to simulate the deposition of an isolated Ni atom and a Ni10 particle on the stoichiometric and reduced anatase TiO2 (101) and tetragonal ZrO2 (101) surfaces. The main purpose of this work is to study the modification of the electronic structure of the oxide induced by the metal, aiming at the understanding of the physical properties of new catalysts for biomass conversion. When the adsorption of a Ni atom takes place on stoichiometric surfaces, no major charge transfer is observed. On reduced titania, and more pronouncedly on reduced zirconia, the Ni atom is negatively charged, provided that the vacancy is in direct contact with the adsorbed metal atom. For Ni10, on titania the bonding is dominated by the hybridization of the metal and the oxide states but we did not find evidence for a direct reduction of the oxide via formation of Ti3 + states. For Ni10 on zirconia, the metal particle is positively charged on the stoichiometric surface and negatively charged on the reduced one but, again, there is no indication of a direct reduction of the oxide. Finally, the reverse oxygen spillover is considered as a possible route to reduce the oxide support. The result is that Ni10 promotes oxygen spillover on titania almost spontaneously, while on zirconia this process is thermodynamically unfavourable.

The inpatient clerkship is a critical time in the development of a medical student as they transition from student to clinician. The attending physician’s approach should be learner centered, emphasizing clinical immersion and autonomy, while still preserving safe patient care. Practices which maximize student learning include reviewing goals and expectations with the student early on, skillful use of the Socratic method, and providing frequent actionable feedback.

Coumarin derivatives are used as fluorescent dyes and medicines. They also have some notable physiological effects, including the acute hepatoxicity and carcinogenicity of certain aflatoxins, the anticoagulant action of dicoumarol, and the antibiotic activity of novobicin and coumerymycin A1. Because the number of drug resistant strains is increasing at present, the synthesis of new antibacterial compounds is one of the critical methods for treating infectious diseases. Therefore, a series of coumarin-substituted derivatives, namely 4-hydroxy- and 7-hydroxycoumarins, and 3-carboxycoumarins were synthesized. 4-Hydroxycoumarin derivatives 4a–c underwent rearrangement reactions. Both 4- and 7-hydroxycoumarins were treated with activated aziridines which produced series of ring-opened products 7, 8, 10, and 11. 3-Carboxy-coumarin amide dimer derivatives 14–21 were prepared by reacting aliphatic alkylamines and alkyldiamines with PyBOP and DIEA. In this study, we use a new technique called modified micro-plate antibiotic susceptibility test method (MMAST), which is more convenient, more efficient, and more accurate than previous methods and only a small amount of the sample is required for the test. Some of the compounds were produced by reactions with acid anhydrides and demonstrated the ability to inhibit Gram-positive microorganisms. The dimer derivatives displayed lower antibacterial activities.

PurposeWorking towards a broader understanding of information provision by agencies responding to crisis situations, the aim of this paper is to examine mandated information provision on the part of law enforcement to survivors of intimate partner violence at the scene of an emergency response.Design/methodology/approachThe authors conducted a detailed content analysis of 1,851 documents supplied by local law enforcement agencies from 755 US cities. A 29‐element coding framework was developed to identify five key content areas of information: the nature of abuse, survivor norms, police information, legal options, and community resources.FindingsThe best represented content areas related to police information, legal options, and community resources. Information on the nature of abuse and survivor hood was dramatically less well represented. Law enforcement understandably privileges that information which involves immediate, concrete action and within which the officer may have a responsibility (for example, to obtain a temporary restraining order). Correlations between city size and the presence of information elements were minimal, while several significant correlations based on region were noted.Originality/valueThis is the first nationwide study of the information that police are required to provide to survivors of intimate partner violence. Understanding the features of this seldom‐discussed yet vital interaction can help IS professionals support practices and protocols of other agencies responding to crisis situations who may be struggling with minimal preparation for information interactions.

The reduction of acetophenone catalysed by Ru(diphosphine)(diamine) complexes, with various diphosphine and diamine ligands, has been investigated theoretically using density functional theory. The results show a correlation between differences in the calculated activation energy (ΔE a) and enantiomeric excess (ee) in ruthenium-based asymmetric hydrogenation catalysts, suggesting that computational procedures may be able to predict the effect on the ee of ligand substitutions. Ligand effects on enantiomeric excess.

New insights into the structural, electronic and catalytic properties of Fe complexes are provided by a density functional theory study of model as well as real [Fe(II)(H)(2)(diphosphine)(diamine)] systems. Calculations conducted using several different functionals on the trans- and cis-isomers of [Fe(II)(H)(2)(S-xylbinap)(S,S-dpen)] complexes show that, as with the [Ru(II)(H)(2)(diphosphine)(diamine)] complexes, the trans-[Fe(II)(H)(2)(diphosphine)(diamine)] complex is the more stable isomer. Analysis of the spin states of the trans-[Fe(II)(H)(2)(diphosphine)(diamine)] complexes also shows that the singlet state is significantly more stable than the triplet and the quintet, as with the [Ru(II)(H)(2)(diphosphine)(diamine)] complexes. Calculations of the catalytic cycle for the hydrogenation of ketones using two model trans-[M(II)(H)(2)(PH(3))(2)(en)] catalysts, where M = Ru and Fe, show that the mechanism of reaction as well as the activation energies are very similar, in particular: (i) the ketone/alcohol hydrogen transfer reaction occurs through the metal-ligand bifunctional mechanism, with energy barriers of 3.4 and 3.2 kcal mol(-1) for the Ru- and Fe-catalysed reactions, respectively; (ii) the heterolytic splitting of H(2) across the M[partial double bond, bottom dashed]N bond for the regeneration of the Ru and Fe catalysts has an activation barrier of 13.8 and 12.8 kcal mol(-1), respectively, and is expected to be the rate determining step for both catalytic systems. The reduction of acetophenone by trans-[M(II)(H)(2)(S-xylbinap)(S,S-dpen)] complexes along two competitive reaction pathways, shows that the intermediates for the Fe catalytic system are similar to those responsible for the high enantioselectivity of (R)-alcohol in those proposed trans-[Ru(II)(H)(2)(S-xylbinap)(S,S-dpen)] catalysed acetophenone hydrogenation reaction. Thus the high enantiomeric excess in the hydrogenation of acetophenone could, in principle, be achieved using Fe catalysts.

High-velocity impact onto a layered glass target produces a very extensive damage pattern exhibiting many distinct morphologies. Material around the penetration cavity is finely comminuted. Under the arrested projectile, the glass is largely intact with spoke-like fracture regions. Around the projectile cavity, needle fragments are formed; they are radial in outer layers and circumferential in inner layers. Extensive radial cracks occur in all layers, but the spacing and frequency of transverse fractures change in each layer. Damage from radial cracks also progresses from being hoop-stress-induced to flexural-induced through the depth of the target. Fan and dicing cracks occur near the periphery of the target. Mesoscale damage features include conventional mist and hackle markings indicating very fast cracks. The map of damage presented herein should be a valuable reference for attempts to model impact damage of glass.

Multiple foregut atresias are exceedingly rare. We present a unique case of combined pyloric and duodenal atresia in a premature neonate. The anomaly appeared to evolve into a closed loop foregut obstruction in the postnatal period. Foregut continuity was established with a gastroduodenostomy, duodenoduodenostomy, and duodenal tapering. The child survived and continued to thrive at 2 years of age.

White coat hypertension (WCH) is considered by some but not all investigators to be a benign condition without increased cardiovascular risk. Pulse wave analysis is a noninvasive method to measure how the reflected pressure wave interacts with central aortic blood pressure (BP) and to assess how it is related to vascular stiffness. The purpose of the study was to compare central aortic BP in normotensive and WCH participants. WCH participants were identified after ambulatory BP monitoring. Normotensive participants served as controls. Using radial artery applanation tonometry, aortic pulse wave analysis was performed. Augmentation index (AI), AI(75), and differences in systolic BP between central aortic and peripheral vasculatures were calculated. Results show a difference in AI, AI(75), (AI standardized to a heart rate of 75 beats per minute), and central aortic systolic pressures between WCH and normotensive participants. The WCH group had significantly higher systolic BP and pulse pressure; however, these were still within the normal range. In summary, WCH participants had increased central aortic pressures compared with normotensives, supporting the potential for increased cardiovascular risk in WCH.

Controlled release silica sol-gels are room temperature processed, porous, resorbable, and biocompatible materials. Many molecules including drugs, proteins, and growth factors can be released from sol-gels, and the quantity and duration of the release can vary widely. Processing parameters render these release properties exquisitely versatile [1]. The synthesis of controlled release sol-gels involves several steps: an acid-catalyzed hydrolysis to form a sol with the molecules included, followed by casting, aging, and drying. Additional steps such as grinding and sieving are required to produce sol-gel granules of a desirable size. In this study, we focus on the synthesis of controlled release sol-gel microspheres by using a novel process, which involves only two steps:sol formation followed by emulsification. Sol-gel microspheres containing either vancomycin (antibiotic) or bupivacaine (analgesic) were successfully synthesized via this synthesis route. Both drugs showed controlled, load-dependent and time-dependent release from the microspheres. The in vitro release properties of sol-gel microspheres were different from those of sol-gel granules produced by grinding and sieving. In comparison to a fast, short-term release from the granules, the release from the microspheres was slower and of longer duration. In addition, the degradation rate of microspheres was significantly slower than that of the granules. These data enable the use of sol-gel powders for controlled long-term release.

© 2015 American Chemical Society. Density functional theory calculations were performed on a set of 13 transannular Diels-Alder (TADA) reactions with 10-18-membered rings. The results were compared with those for bimolecular and intramolecular Diels-Alder reactions in order to investigate the controlling factors of the high TADA reactivities. The effects of tether length, heteroatoms, and alkynyl dienophiles on reactivity were analyzed. We found a correlation between tether length and reactivity, specifically with 12-membered macrocycles undergoing cycloaddition most readily. Furthermore, modifying 12-membered macrocycles by heteroatom substitution and utilizing alkynyl dienophiles enhances the reaction rates up to 105-fold.

Dehydroxylated, hydroxylated and hydrated anatase TiO

Successful predator evasion is essential to the fitness of many animals. Variation in escape behaviour may be adaptive as it reduces predictability, enhancing escape success. High escape velocities and accelerations also increase escape success, but biomechanical factors likely constrain the behavioural range over which performance can be maximized. There may therefore be a trade-off between variation and performance during escape responses. We have used bluegill sunfish (Lepomis macrochirus) escape responses to examine this potential trade-off, determining the full repertoire of escape behaviour for individual bluegill sunfish and linking this to performance as indicated by escape velocity and acceleration. Fish escapes involve an initial C-bend of the body axis, followed by variable steering movements. These generate thrust and establish the escape direction. Directional changes during the initial C-bend were less variable than the final escape angle, and the most frequent directions were associated with high escape velocity. Significant inter-individual differences in escape angles magnified the overall variation, maintaining unpredictability from a predator perspective. Steering in the latter stages of the escape to establish the final escape trajectory also affected performance, with turns away from the stimulus associated with reduced velocity. This suggests that modulation of escape behaviour by steering may also have an associated performance cost. This has important implications for understanding the scope and control of intra- and inter-individual variation in escape behaviour and the associated costs and benefits.

Granulomatous disorders of the skin are diverse and include infectious and non-infectious conditions. They are a source of confusion to many dermatologists and pathologists, including even the most experienced dermatopathologists. Correlation with clinical picture, serology, microbiology and careful morphological examination is essential for accurate diagnosis. Most cases require ancillary histopathological studies to reach a final diagnosis. This review discusses important non-infectious granulomatous conditions of the skin and presents a practical approach when confronted with such entities.

Background: Paraphenylenediamine (PPD) is a coloring agent and potent sensitizer commonly added to henna tattoos to darken tattoo color. Photographic developers contain compounds that cross-react with PPD. Allergic contact dermatitis (ACD) from photo developers has been documented in the literature. Objective: We describe the rare case of a photographer who presented with a 4-year history of recurrent ACD following exposure to photochemicals. History taking revealed that 10 years before presentation, he had received a temporary henna tattoo. Methods: The patient was patch-tested with 4-methylaminophenol sulfate (Metol), the North American Contact Dermatitis Group (NACDG) series, and select other allergens. Results: Patch testing results revealed strong positive reactions to 4-methylaminophenol sulfate and PPD. Conclusion: This is the first report to our knowledge of ACD from a photo developer occurring as a consequence of previous sensitization to PPD from a temporary henna tattoo. Due to the potential for long-term sequelae, an awareness of the risks associated with henna tattoos is warranted.

Scanning tunneling microscopy (STM) experiments combined with density functional theory (DFT) calculations reveal that deposited Cr atoms replace either Na or Cl ions, forming substituting dopants in ultrathin NaCl/Au(111) films. The Cr dopants exchange electrons with the support thus changing the electronic properties of the film and in particular the work function. The Cr atoms spontaneously aggregate near the edges of the bilayer (2L) NaCl islands, forming a new phase in the insulator with a remarkably dense population of Cr dopants. The spectra of differential conductance yield evidence that, compared to the undoped or Cr-poor 2L NaCl films on Au(111), the Cr-rich region shows different interface state, shifted image-potential states, and a reduced work function. This demonstrates the potential of doping ultrathin films to modify their adsorption properties in a desired manner. crosscheck: This document is CrossCheck deposited related_data: Supplementary Information copyright_licence: The Royal Society of Chemistry has an exclusive publication licence for this journal copyright_licence: This article is freely available. This article is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported Licence (CC BY-NC 3.0) history: Received 26 November 2014; Accepted 16 December 2014; Accepted Manuscript published 18 December 2014; Advance Article published 7 January 2015; Version of Record published 28 January 2015 ispartof: Nanoscale vol:7 issue:6 pages:2366-2373 ispartof: location:England status: published

The electronic properties of a single Ru atom and a Ru10 cluster adsorbed on stoichiometric and reduced anatase, a-TiO2(101), and tetragonal zirconia, t-ZrO2(101), surfaces have been determined with density functional theory calculations with Hubbard corrections (DFT+U). The main purpose of the work is to better understand the role of dispersed metals on the surface of titania and zirconia catalysts in conversion of biomass to biofuels. On the stoichiometric surfaces, the metal adsorption does not imply major charge transfers. The situation is different on the reduced surfaces where electron transfer occurs from the oxide to the metal; this effect is more pronounced on zirconia than on titania. On both surfaces, the presence of the Ru nanoparticle favors the removal of O from the surface layers. This can result in the occurrence of O reverse spillover, with displacement of an O atom from a lattice position of the stoichiometric surfaces to a specific adsorption site of Ru10. This process is thermodynamically accessible for both TiO2 and ZrO2 surfaces showing that the metal deposition can result in an easier reduction of the oxide support due to this effect more than to a direct electron transfer from the metal.