bluuebunny/crossref_metadata_2025 huggingface dataset:
Nucleophilic Transfer Reactions of the [Si(C2F5)3]− Moiety
Authors: Schwarze Nico , Steinhauer Simon , Neumann Beate , Stammler Hans‐Georg , Hoge Berthold
Published: November 2016

The tris(pentafluoroethyl)silanide anion is accessible by the deprotonation of Si(C2F5)3H at low temperatures. Subsequent quenching of the resulting salt‐like compounds with suitable electrophiles, such as transition‐metal complexes or Group 14 element halides, leads to a plethora of novel tris(pentafluoroethyl)silane derivatives. This underlines the versatility of Li[Si(C2F5)3] as a powerful nucleophilic transfer reagent.
Regio‐ and Enantioselective Cobalt‐Catalyzed Sequential Hydrosilylation/Hydrogenation of Terminal Alkynes
Authors: Guo Jun , Shen Xuzhong , Lu Zhan
Published: November 2016

A highly regio‐ and enantioselective cobalt‐catalyzed sequential hydrosilylation/hydrogenation of alkynes was developed to afford chiral silanes. This one‐pot method is operationally simple and atom economic. It makes use of relatively simple and readily available starting materials, namely alkynes, silanes, and hydrogen gas, to construct more valuable chiral silanes. Primary mechanistic studies demonstrated that highly regioselective hydrosilylation of alkynes with silanes occurred as a first step, and the subsequent cobalt‐catalyzed asymmetric hydrogenation of the resulting vinylsilanes showed good enantioselectivity.
Interface enhancement between polytetrafluoroethylene and glass fibers modified with a titanate coupler
Authors: Jiang Bo , Zhu Aiping , Zhang Chaoqun , Li Yanxiang
Published: November 2016

The use of glass fibers (GFs), molybdenum disulfide (MoS2), and talc was evaluated to reinforce polytetrafluoroethylene (PTFE) for potential applications in automobile shock absorber pistons. The orthogonal experiment results show that the optimal GF/MoS2/talc/PTFE weight ratio was 2:3:3:92 for the PTFE composite; this ratio resulted in better mechanical properties, hardness, low linear expansion, and wear rate. Chemical coupling and high‐temperature activation treatment on the surface of GF greatly enhanced the interfacial adhesion between the PTFE matrix and GF, as revealed by atomic force microscopy analysis. This resulted in reductions in the wear rate and linear expansion coefficient by two orders of magnitude compared with that of PTFE. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44668.
Hollow Ag/MnO2 Nanostructures with Controllable Shells: Synthesis and Oxygen Reduction Reaction Catalytic Performance
Authors: Zhao Xinfu , Chen Bo , Jiao Xiuling , Zhang Jian , Pang Yingping , Chen Dairong
Published: November 2016

Novel hollow Ag/MnO2 nanostructures with controlled shell composition and structure were designed and synthesized. In the present synthetic procedure, silver nanocrystals were oxidized by KMnO4, and MnO2 was heterogeneously formed on the surface of silver nanocrystals, then released Ag+ was photoreduced to silver adjacent to MnO2. By simply changing the photoreduction moment, simultaneously with or after the addition of KMnO4, hollow Ag/MnO2 structures with different shell architectures—a monolayered shell composed of evenly mixed silver and MnO2 and a double‐layered shell composed of an inner MnO2 layer and an outer silver layer—can be obtained. Furthermore, the morphology of the hollow structure can be tuned by selecting different silver precursors, and the ratio of silver to MnO2 in the shell can also be controlled by adjusting the ratio in the original reaction mixture. Electrochemical measurements revealed significantly enhanced catalytic performance in the oxygen reduction reaction for the prepared hollow structures. Compared with the Ag/MnO2 composite, the onset potentials positively shift by about 50.0 mV and limiting current densities are nearly 2.0 times higher.
Asymmetric Synthesis of Optically Active Spirocyclic Indoline Scaffolds through an Enantioselective Reduction of Indoles
Authors: Borrmann Ruediger , Knop Nils , Rueping Magnus
Published: November 2016

An enantioselective synthesis of spirocyclic indoline scaffolds was achieved by applying an asymmetric iridium‐catalyzed hydrogenation of 3H‐indoles. Low catalyst loadings and mild reaction conditions provide a broad range of differently substituted products with excellent yields and enantioselectivities. The developed methodology allows an efficient synthesis of this important spirocyclic structural motif, which is present in numerous biologically active molecules and privileged structures in medicinal chemistry.
High‐performance liquid chromatography evaluation of the enantiomeric purity of amino acids by means of automated precolumn derivatization with ortho‐phthalaldehyde and chiral thiols
Authors: Kühnreich Raphael , Holzgrabe Ulrike
Published: November 2016

The use of ortho‐phthalaldehyde (OPA) for the derivatization of amino acids (AA) is well known. It enables the separation of the derivatives on common reversed phase columns and improves the sensitivity with fluorescence detection. With the use of a chiral thiol an indirect enantioseparation of chiral amines and AAs is feasible. The major drawback of the OPA‐derivatization is the poor stability of the products. Here, a method with an in‐needle derivatization procedure is optimized to facilitate a quantitative conversion of the AA with OPA and the chiral thiols N‐acetyl‐L‐cysteine or N‐isobutyryl‐L‐cysteine, followed by a subsequent analysis, eluding the stability issue. Both enantiomers of a single AA were separated as OPA‐derivatives with a pentafluorophenyl column and a gradient program consisting of 50 mM sodium acetate buffer pH = 5.0 and acetonitrile. Fluorescence detection is commonly used to achieve sufficient sensitivity. In this study, the enantiomeric impurity of an AA can be detected indirectly with common UV spectrophotometric detection with a limit of quantitation of 0.04%. Seventeen different L‐AAs were tested and the amount of D‐AA for each individual AA was calculated by means of area normalization, which ranged from not detectable up to 4.29%. The recovery of the minor enantiomer of L‐ and D‐AA was demonstrated for three AAs at a 0.04% level and ranged between 92.3 and 113.3%, with the relative standard deviation between 1.7 and 8.2%.
Correlating Structural Features and 207Pb NMR Parameters with the Stereochemical Activity of PbII Lone Pairs in Birefringent Pb[2,6‐bis(benzimidazol‐2‐yl)pyridine] Complexes
Authors: Thompson John R. , Snider David , Wren John E. C. , Kroeker Scott , Williams Vance E. , Leznoff Daniel B.
Published: November 2016

A series of PbII materials containing the highly anisotropic tridentate ligand 2,6‐bis(benzimidazol‐2‐yl)pyridine (bbp) and [Au(CN)2]–, Hg(CN)2 or halide bridging units, [Pb(bbp)Br2]·2H2O, Pb(bbp)I2, [Pb(bbp)I]2(µ‐I)[Au(CN)2], [Pb(bbp)Br]2(µ‐Br)[Au(CN)2], [Pb(bbp)Br2][Hg(CN)2], Pb(bbp)Cl[Au(CN)2]·0.25H2O and Pb(H2O)(bbp)2[Au(CN)2]2, have been prepared, structurally characterised and investigated spectroscopically by 207Pb solid‐state NMR spectroscopy. Of these, five possess similar coordination geometries, providing an ideal series to investigate structural parameters as indicators for stereochemical activity by correlation with the 207Pb chemical shift span parameter (Ω). The bond length of the substituent opposite to the stereochemically active lone pair and the angle between axial ligands were found to correlate weakly with Ω for these compounds (R2 = 0.85 and 0.66, respectively) and an expanded set of compounds with varying components and structures (R2 = 0.60 and 0.67, respectively), which indicates that these (or similar) structural parameters or Ω can be used to estimate the degree of lone‐pair activity. Compounds were also found to be highly birefringent with values ranging from 0.31(5) for Pb(H2O)(bbp)2[Au(CN)2]2 to 0.660(4) for [Pb(bbp)Br2]·2H2O, the latter being amongst the most birefringent compounds reported.
N,N′‐Dimethylated Benzyloxytriazinedione: A Stable Solid Reagent for Acid‐Catalyzed O‐Benzylation
Authors: Fujita Hikaru , Kakuyama Satoshi , Kunishima Munetaka
Published: November 2016

N,N′‐Dimethylated 6‐(benzyloxy)‐1,3,5‐triazine‐2,4(1H,3H)‐dione (DMBOT) has been developed as a triazinedione‐based, stable solid reagent for acid‐catalyzed O‐benzylation. The conceptual basis of the design was to fix the core triazinedione skeleton, and the two methyl groups in positions 1 and 3 were introduced to acheive this. The coproduct of DMBOT can be easily removed by simple washing. Various acid‐ and base‐labile alcohols were O‐benzylated by using DMBOT in the presence of an acid catalyst. In particular, 2,6‐di‐tert‐butylpyridinium trifluoromethanesulfonate, which is a mild, stable, and nonhygroscopic acid catalyst, can be used with DMBOT for this reaction. Compared to other reported methods, DMBOT gave better results for several challenging O‐benzylation reactions under nonbasic conditions.
Hydroxy‐ and Methoxybenzene Derivatives with Benzenediazonium Salts ― Chemical Behavior and Tautomeric Problems
Authors: Micheletti Gabriele , Boga Carla , Forlani Luciano , Del Vecchio Erminia , Zanna Nicola , Mazzanti Andrea , Monari Magda
Published: November 2016

The azo‐coupling reactions between 4‐nitrobenzenediazonium tetrafluoroborate and a series of benzene derivatives bearing at least one electron‐donating hydroxy or methoxy substituent have been studied. Depending on the nucleophile and its relative ratio with the diazonium salt, it was possible to obtain mono‐ and disubstituted products as well as a trisubstituted product for phloroglucinol. The reactions between 3,5‐diaminoanisole or 3,5‐diaminophenol derivatives and 2 equiv. of diazonium salt gave the monosubstituted product in the first case and a diadduct in the second case; X‐ray diffraction analysis revealed a highly symmetric structure for the latter. The different behaviors of hydroxy‐ and methoxy‐substituted compounds was particularly evident for phloroglucinol and 1,3,5‐trimethoxybenzene and may be rationalized on the basis of the different electronic effects of the substituents. The propensities of the aromatic rings to undergo H/D exchange reactions were investigated for a series of substrates, and a comparison of the results obtained provided new insights into this phenomenon and permitted a better explanation of the findings reported here; a new particular interaction competes with the formation of a proton–phloroglucinol σ complex.
Design and Development of Pd‐Catalyzed Aerobic N‐Demethylation Strategies for the Synthesis of Noroxymorphone in Continuous Flow Mode
Authors: Gutmann Bernhard , Cantillo David , Weigl Ulrich , Cox D. Phillip , Kappe C. Oliver
Published: November 2016

Strategies for the generation of noroxymorphone from 14‐hydroxymorphinone are presented. Noroxymorphone is the key intermediate in the synthesis of various opioid antagonists, including naloxone, naltrexone, and nalmefene, as well as mixed agonists‐antagonists such as nalbuphine. The transformation requires removal of the N‐methyl group from the naturally occurring opiates and double‐bond hydrogenation. The pivotal reaction step thereby is an N‐methyl oxidation with colloidal palladium(0) as catalyst and pure oxygen as terminal oxidant. The reaction produces a 1,3‐oxazolidine intermediate, which can be readily hydrolyzed to the corresponding secondary amine. Different reaction sequences and the use of various phenol protecting groups were explored. The most direct route consumes only H2, O2, and H2O as stoichiometric reagents and produces only H2O as a byproduct. Challenges inherent to gas/liquid reactions with oxygen as oxidant have been addressed by developing a continuous flow process.
Muscular pattern in three species of Macrostomum (platyhelminthes, macrostomorpha)
Authors: Adami Mariana L. , Brusa Francisco , Ronderos Jorge R. , Damborenea Cristina
Published: November 2016

Previous studies demonstrated complex architecture of the muscular system of Macrostomum species, especially in the rostrum area and the pharynx. However, little is known about the differences in muscular pattern between species of the genus. This study examines and compares the muscular systems of specimens belonging to three freshwater Macrostomum species (M. quiritium, M. tuba and M. velastylum), labeled with phalloidin‐rhodamine and studied by confocal microscopy. Our results agree with the previous descriptions, confirming that the muscular patterns for the body wall, rostrum area, pharynx and caudal region differ among species. The muscles of the body wall follow the typical architecture, but the number of fibers in the species analyzed varies between dorsal and ventral surfaces, ranging from 80 to 100 fibers, this record being higher than previous observations. The arrangement of the fibers in the rostrum is complex, especially in the brain area. Macrostomum tuba and M. quiritium have a set of two muscles crossing at brain level and forming an “X,” which is not evident in M. velastylum. We identified five different sets of fibers associated to the pharynx and mouth at ventral, medium and deep levels. These different sets are present in all three species studied. The caudal plate in M. tuba has an additional layer of diagonal fibers in the body wall, which is not evident in the other two species. The muscles of the reproductive system are independent of the body wall musculature in the species analyzed, but connected to the intestinal wall by specific fibers that may serve as an anchor. J. Morphol. 278:264–282, 2017. © 2016 Wiley Periodicals,Inc.
Openness to Experience Enhances Creativity: The Mediating Role of Intrinsic Motivation and the Creative Process Engagement
Authors: Tan Chee‐Seng , Lau Xiao‐Shan , Kung Yian‐Thin , Kailsan Renu A/L
Published: November 2016

Studies indicate that there is a positive relationship between openness to experience and creativity. However, relatively little attention has been given to the mechanism of this relationship. On the basis of previous findings, we hypothesized a conceptual model and tested the mediating role of intrinsic motivation and the creative process engagement in the relationship between openness to experience and creativity. One hundred and ninety‐eight undergraduates in Malaysia participated in the study and completed an online measure of openness to new experience, creativity, intrinsic motivation, and the creative process engagement. Consistent with the hypothesis, people who scored high on openness reported high intrinsic motivation. The high motivation enhanced engagement in creativity‐related activities, which in turn, improved self‐rated creativity. The findings not only shed light on mechanisms that underlie in the openness‐creativity linkage but they also highlight the importance of intrinsic motivation and creative process engagement in the linkage. Together, the study extends the effect of personality trait on creativity and offers a new direction for future studies.
Can Creativity Beat Death? A Review and Evidence on the Existential Anxiety Buffering Functions of Creative Achievement
Authors: Perach Rotem , Wisman Arnaud
Published: November 2016

The relationship between creativity and symbolic immortality had been long acknowledged by scholars. In a review of the literature, we found 12 papers that empirically examined the relationship between creativity and mortality awareness using a Terror Management Theory paradigm, overall supporting the notion that creativity plays an important role in the management of existential concerns. Also, a mini meta‐analysis of the impact of death awareness on creativity resulted in a small‐medium weighted mean effect. We examined the existential anxiety buffering functions of creative achievement as assessed by the Creative Achievement Questionnaire in a sample of 108 students. It was found that at high, but not low, levels of creative goals, creative achievement was associated with lower death‐thought accessibility under mortality salience in comparison to controls. To our knowledge, this is the first empirical report of the anxiety buffering functions of creative achievement among people for whom creativity constitutes a central part of their cultural worldview. The current findings support the notion that creative achievement may be an avenue for symbolic immortality, particularly among individuals who value creativity. Implications for understanding death‐related creativity motivations and their impact on individuals and society and for the promotion of creative achievement and creative motivation are discussed.
A New Quantitative‐Based Performance Management Framework for Service Operations
Authors: Safari Arsalan
Published: November 2016

Performance measurement system for individuals and teams is still qualitative and compliance oriented in many organizations. Therefore, most performance evaluations are considered overstated and unreliable by senior management. A new performance management method, discussed in this study, has been designed and developed in a service operation environment to measure and enhance the efficiency and effectiveness of employees and teams based on a new quantitative approach. In this data‐driven approach, all work efforts are evaluated and converted to a comprehensive credit system, allowing aggregation of individual outcomes using a few metrics. All employees need to pass a minimum threshold to start earning benefits. Other key metrics, including quality and risk, can be added to the system to ensure that employees follow standards, restrictions, and other expectations. This model directly aligns performance‐based payouts and rewards to performance outcomes, and therefore improves employees' efficiency and effectiveness. The model has been tested and implemented in several operational units of a large financial institution in North America with outstanding impacts and outcomes. Copyright © 2016 John Wiley & Sons, Ltd.
Intellectual, Human and Structural Capital Effects on Firm Performance as Measured by Tobin's Q
Authors: Hejazi Rezvan , Ghanbari Mehrdad , Alipour Mohammad
Published: November 2016

Today, competitive advantage and success are achieved by strategic management of intellectual capital rather than allocation of physical and financial resources. Although intellectual capital is not a tangible and objective factor, it is often measured in order to compare the market value and development of firms and improve their performance. This paper examines the relationship between intellectual capital and firm performance in Iran using the Pulic's model. In this model, value added intellectual coefficient is used to evaluate firms' intellectual capital. Also, the relationship between intellectual capital and firms' market value is examined. In addition to intellectual capital, the relationship between the components of intellectual capital—that is, human and structural capital—and performance is also investigated. The empirical data is collected from 100 firms listed on Tehran Stock Exchange (TSE) during the period 2000–2006. The results support the hypothesis that human and intellectual capital are positively related to performance (Tobin's Q), and intellectual capital can be taken into consideration for improving the performance of Iranian firms. Also, value added intellectual coefficient proves to be an effective tool that can be used by current decision‐makers in Iran's capital market. The findings and discussions provided in this paper can be of interest to managers and capital market stakeholders. We emphasize that intellectual capital is the main source of value creation in the modern economy. Copyright © 2016 John Wiley & Sons, Ltd.
Evidence for Feedback Regulation Following Cholesterol Lowering Therapy in a Prostate Cancer Xenograft Model
Authors: Masko Elizabeth M. , Alfaqih Mahmoud A. , Solomon Keith R. , Barry William T. , Newgard Christopher B. , Muehlbauer Michael J. , Valilis Nikolaos A. , Phillips Tameika E. , Poulton Susan H. , Freedland Alexis R. , Sun Stephanie , Dambal Shweta K. , Sanders Sergio E. , Macias Everardo , Freeman Michael R. , Dewhirst Mark W. , Pizzo Salvatore V. , Freedland Stephen J.
Published: November 2016

BACKGROUND

Epidemiologic data suggest cholesterol‐lowering drugs may prevent the progression of prostate cancer, but not the incidence of the disease. However, the association of combination therapy in cholesterol reduction on prostate or any cancer is unclear. In this study, we compared the effects of the cholesterol lowering drugs simvastatin and ezetimibe alone or in combination on the growth of LAPC‐4 prostate cancer in vivo xenografts.

METHODS

Proliferation assays were conducted by MTS solution and assessed by Student's t‐test. 90 male nude mice were placed on a high‐cholesterol Western‐diet for 7 days then injected subcutaneously with 1 × 105 LAPC‐4 cells. Two weeks post‐injection, mice were randomized to control, 11 mg/kg/day simvastatin, 30 mg/kg ezetimibe, or the combination and sacrificed 42 days post‐randomization. We used a generalized linear model with the predictor variables of treatment, time, and treatment by time (i.e., interaction term) with tumor volume as the outcome variable. Total serum and tumor cholesterol were measured. Tumoral RNA was extracted and cDNA synthesized from 1 ug of total RNA for quantitative real‐time PCR.

RESULTS

Simvastatin directly reduced in vitro prostate cell proliferation in a dose‐dependent, cell line‐specific manner, but ezetimibe had no effect. In vivo, low continuous dosing of ezetimibe, delivered by food, or simvastatin, delivered via an osmotic pump had no effect on tumor growth compared to control mice. In contrast, dual treatment of simvastatin and ezetimibe accelerated tumor growth. Ezetimibe significantly lowered serum cholesterol by 15%, while simvastatin had no effect. Ezetimibe treatment resulted in higher tumor cholesterol. A sixfold induction of low density lipoprotein receptor mRNA was observed in ezetimibe and the combination with simvastatin versus control tumors.

CONCLUSIONS

Systemic cholesterol lowering by ezetimibe did not slow tumor growth, nor did the cholesterol independent effects of simvastatin and the combined treatment increased tumor growth. Despite lower serum cholesterol, tumors from ezetimibe treated mice had higher levels of cholesterol. This study suggests that induction of low density lipoprotein receptor is a possible mechanism of resistance that prostate tumors use to counteract the therapeutic effects of lowering serum cholesterol. Prostate 77:446–457, 2017. © 2016 Wiley Periodicals, Inc.
Crystal structure of heart 6‐phosphofructo‐2‐kinase/fructose‐2,6‐bisphosphatase (PFKFB2) and the inhibitory influence of citrate on substrate binding
Authors: Crochet Robert B. , Kim Jeong‐Do , Lee Herie , Yim Young‐Sun , Kim Song‐Gun , Neau David , Lee Yong‐Hwan
Published: November 2016

The heart‐specific isoform of 6‐phosphofructo‐2‐kinase/fructose‐2,6‐bisphosphatase (PFKFB2) is an important regulator of glycolytic flux in cardiac cells. Here, we present the crystal structures of two PFKFB2 orthologues, human and bovine, at resolutions of 2.0 and 1.8 Å, respectively. Citrate, a TCA cycle intermediate and well‐known inhibitor of PFKFB2, co‐crystallized in the 2‐kinase domains of both orthologues, occupying the fructose‐6‐phosphate binding‐site and extending into the γ‐phosphate binding pocket of ATP. This steric and electrostatic occlusion of the γ‐phosphate site by citrate proved highly consequential to the binding of co‐complexed ATP analogues. The bovine structure, which co‐crystallized with ADP, closely resembled the overall structure of other PFKFB isoforms, with ADP mimicking the catalytic binding mode of ATP. The human structure, on the other hand, co‐complexed with AMPPNP, which, unlike ADP, contains a γ‐phosphate. The presence of this γ‐phosphate made adoption of the catalytic ATP binding mode impossible for AMPPNP, forcing the analogue to bind atypically with concomitant conformational changes to the ATP binding‐pocket. Inhibition kinetics were used to validate the structural observations, confirming citrate's inhibition mechanism as competitive for F6P and noncompetitive for ATP. Together, these structural and kinetic data establish a molecular basis for citrate's negative feed‐back loop of the glycolytic pathway via PFKFB2. Proteins 2016; 85:117–124. © 2016 Wiley Periodicals, Inc.
Food deprivation facilitates reinstatement of morphine‐induced conditioned place preference: Role of intra‐accumbal dopamine D2‐like receptors in associating reinstatement of morphine CPP with stress
Authors: Sadeghzadeh Fatemeh , Babapour Vahab , Haghparast Abbas
Published: November 2016

The high rate of relapse to drug use is one of the main problems in the treatment of addiction. Stress plays the essential role in drug abuse and relapse; nevertheless, little is known about the mechanisms underlying stress and relapse. Accordingly, the effects of intra‐accumbal administration of Sulpiride, as a dopamine D2‐like receptor antagonist, on an ineffective morphine dose + food deprivation(FD)‐ and morphine priming‐induced reinstatement of conditioned place preference (CPP). About 104 adult male albino Wistar rats weighing 200–280 g were bilaterally implanted by cannula into the nucleus accumbens (NAc). Subcutaneous (sc) injection of morphine (5 mg kg−1) was used daily during a 3‐day conditioning phase. After a 24‐hr “off” period following achievement of extinction criterion, rats were tested for FD‐ and priming‐induced reinstatement of morphine CPP by an ineffective (0.5 mg kg−1, sc) and priming (1 mg kg−1, sc) dose of morphine, respectively. In the next experiments, animals received different doses of intra‐accumbal Sulpiride (0.25, 1, and 4 µg/0.5 µL saline) bilaterally and were subsequently tested for morphine reinstatement. Our findings indicated that the 24‐hr FD facilitated reinstatement of morphine CPP. Furthermore, the D2‐like receptor antagonist attenuated the ineffective morphine dose+ FD‐ and priming‐induced reinstatement of morphine CPP dose‐dependently. Also, contribution of D2‐like receptors in mediation of the ineffective morphine dose+ FD‐induced reinstatement of CPP was greater than morphine priming‐induced reinstatement of CPP. The role of dopaminergic system in morphine reinstatement through a neural pathway in the NAc provides the evidence that D2‐like receptor antagonist can be useful therapeutic targets for reinstatement of morphine CPP.
Principal Covariates Clusterwise Regression (PCCR): Accounting for Multicollinearity and Population Heterogeneity in Hierarchically Organized Data
Authors: Wilderjans Tom Frans , Vande Gaer Eva , Kiers Henk A. L. , Van Mechelen Iven , Ceulemans Eva
Published: November 2016

In the behavioral sciences, many research questions pertain to a regression problem in that one wants to predict a criterion on the basis of a number of predictors. Although in many cases, ordinary least squares regression will suffice, sometimes the prediction problem is more challenging, for three reasons: first, multiple highly collinear predictors can be available, making it difficult to grasp their mutual relations as well as their relations to the criterion. In that case, it may be very useful to reduce the predictors to a few summary variables, on which one regresses the criterion and which at the same time yields insight into the predictor structure. Second, the population under study may consist of a few unknown subgroups that are characterized by different regression models. Third, the obtained data are often hierarchically structured, with for instance, observations being nested into persons or participants within groups or countries. Although some methods have been developed that partially meet these challenges (i.e., principal covariates regression (PCovR), clusterwise regression (CR), and structural equation models), none of these methods adequately deals with all of them simultaneously. To fill this gap, we propose the principal covariates clusterwise regression (PCCR) method, which combines the key idea’s behind PCovR (de Jong & Kiers in Chemom Intell Lab Syst 14(1–3):155–164, 1992) and CR (Späth in Computing 22(4):367–373, 1979). The PCCR method is validated by means of a simulation study and by applying it to cross-cultural data regarding satisfaction with life.
A Multimethod Latent State-Trait Model for Structurally Different And Interchangeable Methods
Authors: Koch Tobias , Schultze Martin , Holtmann Jana , Geiser Christian , Eid Michael
Published: November 2016

A new multiple indicator multilevel latent state-trait (LST) model for the analysis of multitrait–multimethod–multioccasion (MTMM-MO) data is proposed. The LST-COM model combines current CFA-MTMM modeling approaches of interchangeable and structurally different methods and LST modeling approaches. The model enables researchers to specify construct and method factors on the level of time-stable (trait) as well as time-variable (occasion-specific) latent variables and analyze the convergent and discriminant validity among different rater groups across time. The statistical performance of the model is scrutinized by a simulation study and guidelines for empirical applications are provided.
Regularized Latent Class Analysis with Application in Cognitive Diagnosis
Authors: Chen Yunxiao , Li Xiaoou , Liu Jingchen , Ying Zhiliang
Published: November 2016

Diagnostic classification models are confirmatory in the sense that the relationship between the latent attributes and responses to items is specified or parameterized. Such models are readily interpretable with each component of the model usually having a practical meaning. However, parameterized diagnostic classification models are sometimes too simple to capture all the data patterns, resulting in significant model lack of fit. In this paper, we attempt to obtain a compromise between interpretability and goodness of fit by regularizing a latent class model. Our approach starts with minimal assumptions on the data structure, followed by suitable regularization to reduce complexity, so that readily interpretable, yet flexible model is obtained. An expectation–maximization-type algorithm is developed for efficient computation. It is shown that the proposed approach enjoys good theoretical properties. Results from simulation studies and a real application are presented.
Assessment of Arm Port Access Events for 2 Different Port Designs
Authors: Burbridge Brent , Doell Heather J.
Published: November 2016

Background: Patients in our health region received 1 of 2 different arm ports, totally implanted venous access devices (TIVADs), for the management of their malignancies. One of the ports was a nonpower-injectable design and the other was power-injectable. Infusion nurses most commonly access TIVADs in our health region. It was our goal to evaluate infusion nursing access events for these 2 different TIVADs to determine whether nurses experienced any practical, or functional, differences based on port design.

Methods: For this quality assurance project a locally designed, paper-based, questionnaire was developed and administered. Infusion nurses completed the questionnaire after they had accessed an arm TIVAD for intravenous chemotherapy. Sequential access events were tracked for 2 months.

Results: There were no statistically significant differences in the responses related to the 2 different TIVAD designs. Identifying the type of implanted TIVAD for each access event in the study group provided some challenges for the infusion nurses. Eighteen nonpower-injectable ports were erroneously identified as power-injectable.

Conclusions: The results illustrate that our local cancer center infusion nurses were a very experienced group who have been able to adapt to the 2 different arm TIVAD designs. There was no statistically different access event parameters for the 2 different port designs. Additional end-user education may be warranted to improve port design identification.
Development and Testing of a Short Peripheral Intravenous Catheter Insertion Skills Checklist
Authors: Schuster Catherine , Stahl Brian , Murray Connie , Keleekai Nowai L. , Glover Kevin
Published: November 2016

To date, there is no published, psychometrically validated, short peripheral intravenous catheter (PIVC) insertion skills checklist. Creating a valid, reliable, and generalizable checklist to measure PIVC skill is a key step in assessing baseline competence and skill mastery. Based on recognized standards and best practices, the PIVC Insertion Skills Checklist was developed to measure all the steps necessary for a best practice PIVC insertion. This includes the entire process from reading the prescriber's orders to documentation and, if the first attempt is unsuccessful, a second attempt option. Content validity was established using 3 infusion therapy experts. Evidence in support of response process validity is described. The PIVC Insertion Skills Checklist was used by 8 trained raters to assess the PIVC insertion skills, in a simulated environment, of 63 practicing clinicians working on medical and surgical units in a US teaching hospital. Internal consistency of the PIVC Insertion Skills Checklist was α = 0.84. Individual item intraclass correlation coefficients (ICCs) between rater and gold standard observations ranged from − 0.01 to 1.00 and total score ICC was 0.99 (95% confidence interval, 0.99–0.99). The current study offers validity and reliability evidence to support the use of the PIVC Insertion Skills Checklist to measure PIVC insertion skill of clinicians in a simulated environment.
Analysis of hohlraum energetics of the SG series and the NIF experiments with energy balance model
Authors: Ren Guoli , Liu Jie , Huo Wenyi , Lan Ke
Published: November 2016

The basic energy balance model is applied to analyze the hohlraum energetics data from the Shenguang (SG) series laser facilities and the National Ignition Facility (NIF) experiments published in the past few years. The analysis shows that the overall hohlraum energetics data are in agreement with the energy balance model within 20% deviation. The 20% deviation might be caused by the diversity in hohlraum parameters, such as material, laser pulse, gas filling density, etc. In addition, the NIF's ignition target designs and our ignition target designs given by simulations are also in accordance with the energy balance model. This work confirms the value of the energy balance model for ignition target design and experimental data assessment, and demonstrates that the NIF energy is enough to achieve ignition if a 1D spherical radiation drive could be created, meanwhile both the laser plasma instabilities and hydrodynamic instabilities could be suppressed.
The Feasibility and Effects of Acupuncture in an Adolescent Nordic Ski Population
Authors: Garlanger Kristin L. , Fredericks William H. , Do Alexander , Bauer Brent A. , Laskowski Edward R.
Published: November 2016

Background

Studies investigating the use and effectiveness of acupuncture in adults after exercise have been well documented. Fewer studies involving acupuncture have been completed in the adolescent athlete population. To our knowledge, there are no published studies that investigate the use of acupuncture in adolescent athletes within their field of play.

Objective

To primarily assess the feasibility of performing acupuncture in adolescent Nordic skiers within their athletic environment, and secondarily to measure the effect of acupuncture on muscle soreness and sense of well‐being.

Design

Prospective feasibility study.

Setting

Local outdoor cross country ski trails and indoor lodge.

Participants

Fifteen healthy participants (80% female, 20% male; age 14‐17 years) were involved on at least 1 of 5 treatment days.

Intervention

Fifteen‐minute treatments were administered using traditional needle acupuncture following the first 5 consecutive Nordic Ski Team practices of the season in an attempt to capture the effect of acupuncture on delayed‐onset muscle soreness (DOMS). Acupuncture points specific to muscle groups in the lower limbs that are commonly reported as painful during Nordic skiing were chosen. Pre‐ and posttreatment surveys included visual analogue scales (VAS) to track participant responses.

Outcome Measures

Time, cost, side effects, and participant to provider ratio was observed to determine feasibility. Effect on muscle soreness and sense of well‐being was measured via pre‐ and posttreatment VAS (0‐10) rating analyses.

Results

Total time required by research staff on treatment days was 90 minutes; total cost, $1500; temperature range, −13.9°C to −2.8°C, and largest participant to acupuncturist ratio, 7:1. No major side effects occurred. The majority (73%) of participants reported minimal side effects; most common was treatment site pain. The overall pre‐ to posttreatment effect on muscle soreness (average over 5 days) demonstrated significantly improved posttreatment scores (P = .04). The effect of the day (average over pre‐ and posttreatment values) demonstrated significantly higher muscle soreness scores on day 3 versus day 1 (P = .03). At study completion, all participants indicated that they would consider acupuncture in the future and would recommend treatments to friends or teammates.

Conclusion

Providing acupuncture to adolescent Nordic ski athletes in the practice field under extreme temperatures is feasible with the appropriate resources. Despite mild side effects, acupuncture was well received by the athletes. Lessons learned from this trial can provide a framework for delivering acupuncture to other athletes in their training environment.

Level of Evidence

IV
Blended learning y el desarrollo de la comunicación científica en un programa de especialización dental
Authors: Muñoz Francisca , Matus Olga , Pérez Cristhian , Fasce Eduardo
Published: November 2016

Introducción: Para fomentar el aprendizaje permanente, los especialistas dentales deben ser capaces de evaluar e integrar las tendencias emergentes a una práctica clínica basada en la evidencia. Por esta razón, el desarrollo de habilidades de comunicación científica es muy necesario.
Objetivo: El objetivo principal de este estudio fue relacionar el cambio en los niveles autopercibidos de competencia en comunicación científica con el grado de satisfacción con la metodología blended learning (b-learning) utilizada para su desarrollo en estudiantes de un programa de especialización odontológica.
Método: Se diseñó un taller destinado a apoyar el desarrollo de competencias en comunicación científica en los alumnos de un programa de especialización en Endodoncia, utilizando tecnologías de la información y la comunicación (TIC), a través de la plataforma Moodle® . Se evaluó la efectividad de la estrategia, comparando los niveles de competencia en comunicación científica autopercibidos por los alumnos al iniciar y al finalizar el taller en comunicación científica, el grado de satisfacción que tuvieron los alumnos con esta estrategia y la relación entre la satisfacción demostrada por los alumnos con la estrategia y su efectividad.
Resultados: Se pudo observar un aumento de las competencias en comunicación científica autopercibidas por los estudiantes luego de realizar el taller (p < 0.001). Asimismo, los participantes se mostraron satisfechos con la metodología y se encontraron relaciones estadísticamente significativas al evaluar la relación entre la diferencia de las mediciones en el nivel autopercibido de competencias en comunicación científica y las dimensiones del cuestionario de satisfacción con la metodología b-learning (p < 0.05).
Conclusiones: La metodología b-learning probó ser efectiva para el desarrollo de competencias en comunicación científica para estos estudiantes, quienes expresaron altos niveles de satisfacción con la estrategia b-learning, lo que se relacionó con la efectividad de la misma.
H3Africa AWI-Gen Collaborative Centre: a resource to study the interplay between genomic and environmental risk factors for cardiometabolic diseases in four sub-Saharan African countries
Authors: Ramsay M. , Crowther N. , Tambo E. , Agongo G. , Baloyi V. , Dikotope S. , Gómez-Olivé X. , Jaff N. , Sorgho H. , Wagner R. , Khayeka-Wandabwa C. , Choudhury A. , Hazelhurst S. , Kahn K. , Lombard Z. , Mukomana F. , Soo C. , Soodyall H. , Wade A. , Afolabi S. , Agorinya I. , Amenga-Etego L. , Ali S. A. , Bognini J. D. , Boua R. P. , Debpuur C. , Diallo S. , Fato E. , Kazienga A. , Konkobo S. Z. , Kouraogo P. M. , Mashinya F. , Micklesfield L. , Nakanabo-Diallo S. , Njamwea B. , Nonterah E. , Ouedraogo S. , Pillay V. , Somande A. M. , Tindana P. , Twine R. , Alberts M. , Kyobutungi C. , Norris S. A. , Oduro A. R. , Tinto H. , Tollman S. , Sankoh O.
Published: November 2016

Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.
Amphibian conservation: clarifications to comments from Andreone
Authors: Muths Erin , Fisher Robert N.
Published: November 2016

We appreciate the comments from Andreone (2016) regarding our proposed alternative strategy for addressing the amphibian crisis. Andreone recognizes the utility of an Incident Command System approach but doubts the feasibility of implementation at an international level. We stated in our original article, however, that ‘the feasibility of our suggestion is debatable, but our point is that radically different approaches are necessary to effectively manage the largest extinction event in modern history’ (Muths & Fisher, 2015). There are examples of where such top-down strategies are being applied; e.g. for the brown tree snake Boiga irregularis (Stanford & Rodda, 2007), and biosecurity planning for Micronesia and Hawaii (NAVFAC Pacific, 2016). Another example is presented by Andreone. In Madagascar a community-wide conservation plan has been developed complete with prioritization of specific actions (Andreone, 2016). As with any top-down strategy, challenges will surface, especially when making decisions that affect economics. We note this caveat in our article, and Andreone points out such issues in Madagascar, where there are mismatches in priorities between biodiversity conservation and civil needs. Our suggestion is that a new paradigm needs to be considered given the gravity of amphibian decline, and one option may be to take a global approach focusing on specific, major threats. Application of an Incident Command System would not necessitate competition with, or emasculation of, local conservation priorities or actions.
Bilingual language acquisition: The role of input and experience
Authors: ABUTALEBI JUBIN , CLAHSEN HARALD
Published: November 2016

The question of how much language a child can learn by modelling the patterns she is exposed to in the environment represents an age-old and persistent controversy in language-acquisition research. On a number of occasions researchers felt confident enough to claim that the controversy had been resolved, in favour of their own viewpoint, of course. One such attempt was Skinner's (1957) behaviourist view of language development, which gave a prominent if not exclusive role to input and experience. After Chomsky's (1959) landmark review, however, Skinner's account was left in pieces and was not further pursued by many. A more recent attempt comes from usage-based accounts according to which children directly build linguistic categories and rules from the language they hear around them. Some believe that these accounts have resolved the controversy for good and have ‘overturned’ alternative less experience-driven approaches (e.g., Ibbotson & Tomasello, 2016; Dabrowska, 2015). Yet, casual inspection of recent research articles reveals that this announcement may be somewhat premature; see, for example, Everaert, Huybregts, Chomsky, Berwick and Bolhuis (2015), Boxell's (2016) rebuttal of Dabrowska (2015), and many acquisition studies published in the journal Language Acquisition.
Self-Assessed Health into Late Adulthood
Authors: Graf Allyson S. , Hicks Patrick Julie
Published: November 2016

Abstract. Self-assessed health (SAH) is the personal assessment of one’s own health ( Idler & Benyamini, 1997 ; Jylhä, 2009 ). It is often measured using a single item asking whether adults rate their health as excellent, very good, good, fair, or poor. When measured at a single point in time, SAH relates to a variety of short-term and long-term health outcomes and behaviors, including morbidity, healthcare utilization, and mortality ( Benyamini, 2008 ; Mossey & Shapiro, 1982 ; Westerhof & Wurm, 2015 ). Recently, attention has shifted away from examining SAH at a single point in time toward understanding whether SAH trajectories can better predict health outcomes ( Ayyagari et al., 2012 ; Schmitz et al., 2013 ). Therefore, it is critical to understand the factors contributing to the SAH process. This article provides a multidisciplinary overview of SAH and SAH change while illustrating the benefits of adopting a lifespan approach in future research. The current SAH literature, including cross-sectional and longitudinal studies, is used to examine what is known about the SAH process into late adulthood. From the literature, it is clear SAH is a multidimensional construct, susceptible to age-related change and sociohistorical contexts. Understanding the developmental mechanisms and multiple influences underlying change, however, may help further the use of SAH as a life-long health-promotion tool. Lifespan concepts are applied to expand discussion and recommendations are made concerning the application of alternative variables and methodologies. Future studies of SAH should consider these personal perceptions of health not only as predictors of health outcomes in later life, but also as tools for effective health promotion in everyday life.
Monitoring and Promoting Old Age Health Stabilization in Real Life
Authors: Martin Mike , Jäncke Lutz , Röcke Christina
Published: November 2016

Abstract. Research on aging in different domains largely focuses on age-related decrements or intervention-related improvements, often in controlled laboratory conditions or with psychometric tests of maximum ability or traits. This special issue on monitoring and promoting old-age health stabilization in real life focuses on the short-term and long-term age-related stabilization and maintenance in diverse psychological areas, including well-being, self-esteem, subjective health, and social interactions. One central focus in all studies is the clear focus on behaviors in real-life contexts. The papers both review and present ways in which new technologies and research approaches can provide novel opportunities for monitoring and promoting the stabilization of various aspects of health and quality of life in the daily lives of healthy older adults.
Laboratory Sharing to Improve Rock Deformation Research
Authors: Kronenberg A. , Hirth G. , Lapusta N. , Chester J. , Freed A. , Marone C. , Tullis T.
Published: November 2016

An ever-growing group of scientists seeks to integrate rock deformation labs from across the United States into one shared national facility.