bluuebunny/crossref_metadata_2025 huggingface dataset:
Water‐Induced Formation, Characterization, and Photoluminescence of Carbon Nanotube‐Based Composites of Gadolinium(III) and Platinum(II) Dithiolenes
Authors: Begum Ameerunisha , Tripathi Kumud M. , Sarkar Sabyasachi
Published: October 2014

Understanding the nature of interactions of targeted drug‐delivery vehicles, such as functionalized carbon nanotubes (f‐CNTs) and their composites, with a cell or its organelles or DNA, where water is a major constituent, requires molecular‐level understanding of f‐CNTs with analogous chemical systems. The nature of interaction has not yet been explored within the scope of formation of giant aggregates by self‐assembly processes. Crystals of platinum(II) dithiolene [Pt(mnt)2][PPh4]2 (1) and gadolinium(III) dithiolene [Gd(mnt)3][PPh4]3 (2) (mnt=maleonitrile dithiolate) form nanospheres (diameter 88 nm) and nanoflowers (400–600 nm) in acetonitrile/water and DMF/water solvent mixtures, respectively. The formation of nanospheres or nanoflowers is proposed to be a water‐induced phenomenon. These nanospheres and nanoflowers interact with f‐CNTs by forming either spherical supramolecular assemblies (3, diameter up to 45. 5 μm) in the case of platinum(II) dithiolene or composite flowers (4) with CNT buckling for gadolinium(III) dithiolene. Both nanostructures, (3) and (4), show emission upon excitation at a range of wavelengths (λex=385–560 nm). The fluorescence emissions of the composite materials 3 and 4 are proposed to be due to separation of energy states of the nanospheres of 1 or the nanoflowers of 2 by the energy states of the f‐CNTs, leading to the possibility of new electronic transitions.
Microwave‐Assisted Tandem Organocatalytic Peptide‐Coupling Intramolecular aza‐Michael Reaction: α,β‐Unsaturated N‐Acyl Pyrazoles as Michael Acceptors
Authors: Sánchez‐Roselló María , Mulet Cristina , Guerola Marta , del Pozo Carlos , Fustero Santos
Published: October 2014

Conjugated N‐acyl pyrazoles have been successfully employed in the organocatalytic enantioselective intramolecular aza‐Michael reaction as ester surrogates. Bifunctional squaramides under microwave irradiation provided the best results in this transformation. Furthermore, this protocol has been combined with a peptide‐coupling reaction in a tandem sequence. The final products were easily converted into the corresponding ethyl esters.
Enantiopure Narrow Bite‐Angle POP Ligands: Synthesis and Catalytic Performance in Asymmetric Hydroformylations and Hydrogenations
Authors: Fernández‐Pérez Héctor , Benet‐Buchholz Jordi , Vidal‐Ferran Anton
Published: October 2014

Herein is reported the preparation of a set of narrow bite‐angle P–OP ligands the backbone of which contains a stereogenic carbon atom. The synthesis was based on a Corey–Bakshi–Shibata (CBS)‐catalyzed asymmetric reduction of phosphomides. The structure of the resulting 1,1‐P–OP ligands, which was selectively tuned through adequate combination of the configuration of the stereogenic carbon atom, its substituent, and the phosphite fragment, proved crucial for providing a rigid environment around the metal center, as evidenced by X‐ray crystallography. These new ligands enabled very good catalytic properties in the Rh‐mediated enantioselective hydrogenation and hydroformylation of challenging and model substrates (up to 99 % ee). Whereas for asymmetric hydrogenation the optimal P–OP ligand depended on the substrate, for hydroformylation, a single ligand was the highest‐performing one for almost all studied substrates: it contains an R‐configured stereogenic carbon atom between the two phosphorus ligating groups, and an S‐configured 3,3′‐diphenyl‐substituted biaryl unit.
Carbonic Anhydrase‐Mimetic Bolaamphiphile Self‐Assembly for CO2 Hydration and Sequestration
Authors: Kim Min‐Chul , Lee Sang‐Yup
Published: October 2014

A biomimetic catalyst was prepared through the self‐assembly of a bolaamphiphilic molecule with histidine moieties for the sequestration of carbon dioxide. The histidyl bolaamphiphilic molecule bis(N‐α‐amidohistidine)‐1,7‐heptane dicarboxylate has been synthesized and self‐assembled to produce analogues of the active sites of carbonic anhydrase (CA) after association with Zn2+ ions. Spectroscopic analysis demonstrated the coordination of the Zn2+ ions with histidine imidazole moieties, which is the core conformation of CA active sites. The Zn‐associated self‐assembly worked as a CA‐mimetic catalyst that shows catalytic activity for CO2 hydration. Evaluation of the kinetics of using para‐nitrophenylacetate revealed that the kinetic parameters of the CA‐mimetic catalyst were maximized at the optimal Zn concentration and that excess Zn ions resulted in deteriorated catalytic activity. The performance of the CA‐mimetic catalyst was enhanced by changing the pH value and temperature of the reaction, which implies that the hydrolysis of the substrate is the rate‐determining step. The catalyst‐assisted sequestration of CO2 was demonstrated by CaCO3 precipitation upon the addition of Ca2+ ions. This study offers an easy way to prepare enzyme analogues for CO2 sequestration through the self‐assembly of bolaamphiphile molecules with designer biochemical moieties.
Expanded‐Ring N‐Heterocyclic Carbenes for the Stabilization of Highly Electrophilic Gold(I) Cations
Authors: Phillips Nicholas , Dodson Tristan , Tirfoin Rémi , Bates Joshua I. , Aldridge Simon
Published: October 2014

Strategies for the synthesis of highly electrophilic AuI complexes from either hydride‐ or chloride‐containing precursors have been investigated by employing sterically encumbered Dipp‐substituted expanded‐ring NHCs (Dipp=2,6‐iPr2C6H3). Thus, complexes of the type (NHC)AuH have been synthesised (for NHC=6‐Dipp or 7‐Dipp) and shown to feature significantly more electron‐rich hydrides than those based on ancillary imidazolylidene donors. This finding is consistent with the stronger σ‐donor character of these NHCs, and allows for protonation of the hydride ligand. Such chemistry leads to the loss of dihydrogen and to the trapping of the [(NHC)Au]+ fragment within a dinuclear gold cation containing a bridging hydride. Activation of the hydride ligand in (NHC)AuH by B(C6F5)3, by contrast, generates a species (at low temperatures) featuring a [HB(C6F5)3]− fragment with spectroscopic signatures similar to the “free” borate anion. Subsequent rearrangement involves BC bond cleavage and aryl transfer to the carbophilic metal centre. Under halide abstraction conditions utilizing Na[BArf4] (Arf=C6H3(CF3)2‐3,5), systems of the type [(NHC)AuCl] (NHC=6‐Dipp or 7‐Dipp) generate dinuclear complexes [{(NHC)Au}2(μ‐Cl)]+ that are still electrophilic enough at gold to induce aryl abstraction from the [BArf4]− counterion.
Energetic N,N′‐Ethylene‐Bridged Bis(nitropyrazoles): Diversified Functionalities and Properties
Authors: Yin Ping , Zhang Jiaheng , Parrish Damon A. , Shreeve Jean'ne M.
Published: October 2014

A new class of N,N′‐ethylene‐bridged bis(nitropyrazoles) was synthesized and fully characterized. The highly efficient formation of the N,N′‐ethylene bridge was accomplished using dibromoethane and ammonium or potassium pyrazolate. Further functional‐group transformations of diaminobis(pyrazole) and dichlorobis(pyrazole) gave rise to diversified derivatives, including dinitramino‐, diazido‐ and hexanitrobis(pyrazole). Single‐crystal X‐ray diffractions were obtained for hexanitro and diazido derivatives to illustrate the structural characteristics. Heats of formation and detonation performance were calculated by using Gaussian 03 and EXPLO5 v6.01 programs, respectively. Because of the different functionalized groups, the impact and friction sensitivities of these new compounds range from insensitive to sensitive. Among them, the hexanitro derivative displays the most promising overall energetic properties (density (ρ)=1.84 g cm−3; decomposition temperature (Td)=250 °C; detonation pressure (P)=34.1 GPa; detonation velocity (vD)=8759 m s−1; impact sensitivity (IS)=25 J; friction sensitivity (FS)=160 N), which is competitive with those of 1,3,5‐trinitrotriazacyclohexane (ρ=1.80 g cm−3; Td=205 °C; P=35.0 GPa; vD=8762 m s−1; IS=7 J; FS=120 N).
N‐Oxide 1,2,4,5‐Tetrazine‐Based High‐Performance Energetic Materials
Authors: Wei Hao , Gao Haixiang , Shreeve Jean'ne M.
Published: October 2014

One route to high density and high performance energetic materials based on 1,2,4,5‐tetrazine is the introduction of 2,4‐di‐N‐oxide functionalities. Based on several examples and through theoretical analysis, the strategy of regioselective introduction of these moieties into 1,2,4,5‐tetrazines has been developed. Using this methodology, various new tetrazine structures containing the N‐oxide functionality were synthesized and fully characterized using IR, NMR, and mass spectroscopy, elemental analysis, and single‐crystal X‐ray analysis. Hydrogen peroxide (50 %) was used very effectively in lieu of the usual 90 % peroxide in this system to generate N‐oxide tetrazine compounds successfully. Comparison of the experimental densities of N‐oxide 1,2,4,5‐tetrazine compounds with their 1,2,4,5‐tetrazine precursors shows that introducing the N‐oxide functionality is a highly effective and feasible method to enhance the density of these materials. The heats of formation for all compounds were calculated with Gaussian 03 (revision D.01) and these values were combined with measured densities to calculate detonation pressures (P) and velocities (νD) of these energetic materials (Explo 5.0 v. 6.01). The new oxygen‐containing tetrazines exhibit high density, good thermal stability, acceptable oxygen balance, positive heat of formation, and excellent detonation properties, which, in some cases, are superior to those of 1,3,5‐tritnitrotoluene (TNT), 1,3,5‐trinitrotriazacyclohexane (RDX), and octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine (HMX).
Doubly robust imputation procedures for finite population means in the presence of a large number of zeros
Authors: Haziza David , Nambeu Christian‐Olivier , Chauvet Guillaume
Published: October 2014

Single imputation is often used in surveys to compensate for item nonresponse. In some cases, the variable requiring imputation contains a large amount of zeros. This is especially frequent in business surveys that collect economic variables. Motivated by a mixture regression model, we propose three imputation procedures and study their properties in terms of bias and variance. We show that these procedures are doubly robust, leading to consistent estimators of the finite population mean if either the imputation model or the nonresponse model is well specified. For the proposed procedures, we consider a jackknife variance estimator, which is consistent for the true variance, provided the overall sampling fraction is negligible. Finally, the results of a simulation study comparing the performance of point and variance estimators in terms of relative bias and mean square error are presented. The Canadian Journal of Statistics 42: 650–669; 2014 © 2014 Statistical Society of Canada
Statins in the Elderly: A Patient‐Focused Approach
Authors: Wilmot Kobina A. , Khan Abdullah , Krishnan Sandeep , Eapen Danny J. , Sperling Laurence
Published: October 2014

Individuals age >65 years represent the fastest‐growing subpopulation in the United States. Although these individuals with the highest cardiovascular risk profile would be anticipated to be the most aggressively treated, paradoxically, treatment and baseline risk are inversely related. Presumably, the elderly population would benefit from high‐intensity statin therapy; however, as per the 2013 American College of Cardiology/American Heart Association guidelines, given the scarcity of evidence in patients age >75, there are only sufficient data from randomized controlled trials to support use of moderate‐intensity statin therapy for secondary prevention. Despite evidence demonstrating statins are beneficial in the elderly, the decision to initiate and sustain treatment should be a well‐informed and collaborative decision. One must balance the benefits (secondary atherosclerotic cardiovascular prevention, stroke reduction, decreased morbidity and mortality) with the potential risks to the elderly (altered metabolism, comorbidities, polypharmacy and drug‐drug interactions, side effects, cognitive limitations, and cost).
Application of Appropriate Use Criteria to Cardiac Stress Testing in the Hospital Setting: Limitations of the Criteria and Areas for Improved Practice
Authors: Gertz Zachary M. , O'Donnell William , Raina Amresh , Litwack Andrew J. , Balderston Jessica R. , Goldberg Lee R.
Published: October 2014

Background

Imaging cardiac stress test use has risen significantly, leading to the development of appropriate use criteria. Prior studies have suggested the rate of inappropriate testing is 13% to 14%, but inappropriate testing in hospitalized patients has not been well studied.

Hypothesis

Appropriate use of stress testing in hospitalized patients is not comparable to the ambulatory setting.

Methods

We studied 459 consecutive patients referred for imaging stress tests (nuclear imaging or stress echocardiography) at a single institution over a 6‐month period. Appropriate use was determined by research cardiologists blinded to patient outcomes.

Results

Most tests (68%) were in patients with chest pain or possible acute coronary syndrome (ACS). Another 20% were for preoperative evaluation. The rate of inappropriate testing was 13%. Imaging modality did not correlate with appropriate use. Only 2% of the chest pain or possible ACS were inappropriate, compared to 49% of the preoperative exams (P < 0.001). The most common reason a test was considered inappropriate was for a low‐risk patient for preoperative exam (77% of inappropriate tests). Using Thrombolysis in Myocardial Infarction score 0 to define inappropriate testing in the possible ACS cohort might make an additional 27% inappropriate.

Conclusions

The rate of inappropriate use of cardiac stress testing with imaging in the inpatient setting is similar to that in the ambulatory setting. However, there is wide variation in inappropriate testing based on the indication for the test. Taking risk into consideration in possible ACS patients could result in a larger number of tests being considered inappropriate.
Assessing benefit in trials: Are we making progress in assessing progression in cancer clinical trials?
Authors: Dancey Janet E.
Published: October 2014

Intermediate endpoints that better capture the benefits of treatment and patient outcomes will facilitate trial conduct and ultimately treatment decisions for individual patients. Whether the current crop of newer endpoints will improve trial conduct and the interpretation of outcomes will require further evaluation.
Small cell lung cancer: Where do we go from here?
Authors: Byers Lauren Averett , Rudin Charles M.
Published: October 2014

Small cell lung cancer (SCLC) is an aggressive disease that accounts for approximately 14% of all lung cancers. In the United States, approximately 31,000 patients are diagnosed annually with SCLC. Despite numerous clinical trials, including at least 40 phase 3 trials since the 1970s, systemic treatment for patients with SCLC has not changed significantly in the past several decades. Consequently, the 5‐year survival rate remains low at <7% overall, and most patients survive for only 1 year or less after diagnosis. Unlike nonsmall cell lung cancer (NSCLC), in which major advances have been made using targeted therapies, there are still no approved targeted drugs for SCLC. Significant barriers to progress in SCLC include 1) a lack of early detection modalities, 2) limited tumor tissue for translational research (eg, molecular profiling of DNA, RNA, and/or protein alterations) because of small diagnostic biopsies and the rare use of surgical resection in standard treatment, and 3) rapid disease progression with poor understanding of the mechanisms contributing to therapeutic resistance. In this report, the authors review the current state of SCLC treatment, recent advances in current understanding of the underlying disease biology, and opportunities to advance translational research and therapeutic approaches for patients with SCLC. Cancer 2015;121:664–672. © 2014 American Cancer Society.
Air Electrode for the Lithium–Air Batteries: Materials and Structure Designs
Authors: Wen Zhaoyin , Shen Chen , Lu Yan
Published: October 2014

The lithium–air battery, considered to be a promising candidate for future applications such as electric vehicles and energy storage, has captured worldwide attention recently because of its superhigh specific energy density even rivaling that of gasoline. This Review covers the most recent and significant scientific progress made in the fields relevant to Li–air batteries, with emphasis on the structure design of air electrodes. After a brief introduction to the operation principles and cathode electrochemical reactions, a discussion of the design and optimization of the cathode structure is presented sequentially, and the final conclusion remarks on future challenges and perspectives. The aim is to provide a better understanding of the effect of the cathode structure on the performance of the promising metal–air battery technologies, and to consider their challenges and perspectives in the future.
Monitoring Solid Oxide CO2 Capture Sorbents in Action
Authors: Keturakis Christopher J. , Ni Fan , Spicer Michelle , Beaver Michael G. , Caram Hugo S. , Wachs Israel E.
Published: October 2014

The separation, capture, and storage of CO2, the major greenhouse gas, from industrial gas streams has received considerable attention in recent years because of concerns about environmental effects of increasing CO2 concentration in the atmosphere. An emerging area of research utilizes reversible CO2 sorbents to increase conversion and rate of forward reactions for equilibrium‐controlled reactions (sorption‐enhanced reactions). Little fundamental information, however, is known about the nature of the sorbent surface sites, sorbent surface–CO2 complexes, and the CO2 adsorption/desorption mechanisms. The present study directly spectroscopically monitors Na2O/Al2O3 sorbent–CO2 surface complexes during adsorption/desorption with simultaneous analysis of desorbed CO2 gas, allowing establishment of molecular level structure–sorption relationships between individual surface carbonate complexes and the CO2 working capacity of sorbents at different temperatures.
Akhirin regulates the proliferation and differentiation of neural stem cells in intact and injured mouse spinal cord
Authors: Abdulhaleem M Felemban Athary , Song Xiaohong , Kawano Rie , Uezono Naohiro , Ito Ayako , Ahmed Giasuddin , Hossain Mahmud , Nakashima Kinichi , Tanaka Hideaki , Ohta Kunimasa
Published: October 2014

Although the central nervous system is considered a comparatively static tissue with limited cell turnover, cells with stem cell properties have been isolated from most neural tissues. The spinal cord ependymal cells show neural stem cell potential in vitro and in vivo in injured spinal cord. However, very little is known regarding the ependymal niche in the mouse spinal cord. We previously reported that a secreted factor, chick Akhirin, is expressed in the ciliary marginal zone of the eye, where it works as a heterophilic cell‐adhesion molecule. Here, we describe a new crucial function for mouse Akhirin (M‐AKH) in regulating the proliferation and differentiation of progenitors in the mouse spinal cord. During embryonic spinal cord development, M‐AKH is transiently expressed in the central canal ependymal cells, which possess latent neural stem cell properties. Targeted inactivation of the AKH gene in mice causes a reduction in the size of the spinal cord and decreases BrdU incorporation in the spinal cord. Remarkably, the expression patterns of ependymal niche molecules in AKH knockout (AKH−/−) mice are different from those of AKH+/+, both in vitro and in vivo. Furthermore, we provide evidence that AKH expression in the central canal is rapidly upregulated in the injured spinal cord. Taken together, these results indicate that M‐AKH plays a crucial role in mouse spinal cord formation by regulating the ependymal niche in the central canal. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 75: 494–504, 2015
Foxp3+ regulatory T‐cell homeostasis quantitatively differs in murine peripheral lymph nodes and spleen
Authors: Milanez‐Almeida Pedro , Meyer‐Hermann Michael , Toker Aras , Khailaie Sahamoddin , Huehn Jochen
Published: October 2014

Regulatory T (Treg) cells are essential for maintaining self‐tolerance and modulating inflammatory immune responses. Treg cells either develop within the thymus or are converted from CD4+ naive T (Tnaive) cells in the periphery. The Treg‐cell population size is tightly controlled and Treg‐cell development and homeostasis have been intensively studied; however, quantitative information about mechanisms of peripheral Treg‐cell homeostasis is lacking. Here we developed the first mathematical model of peripheral Treg‐cell homeostasis, incorporating secondary lymphoid organs as separate entities and encompassing factors determining the size of the Treg‐cell population, namely thymic output, homeostatic proliferation, peripheral conversion, transorgan migration, apoptosis, and the Tnaive‐cell population. Quantitative data were collected by monitoring Tnaive‐cell homeostasis and Treg‐cell rebound after selective in vivo depletion of Treg cells. Our model predicted the previously unanticipated possibility that Treg cells regulate migration of Tnaive cells between spleen and peripheral lymph nodes (LNs), whereas migration of Treg cells between these organs can largely be neglected. Furthermore, our simulations suggested that peripheral conversion significantly contributed to the maintenance of the Treg‐cell population, especially in LNs. Hence, we provide the first estimation of the peripheral Treg‐cell conversion rate and propose additional facets of Treg‐cell‐mediated immune regulation that may previously have escaped attention.
Increasing inflationary T‐cell responses following transient depletion of MCMV‐specific memory T cells
Authors: Sims Stuart , Klenerman Paul
Published: October 2014

Murine CMV (MCMV) infection induces effector CD8+ T cells that continue to increase in frequency after acute infection (“inflation”) and are stably maintained at a high frequency, with up to 20% of the CD8+ T‐cell compartment being specific for one epitope, although the flexibility and turnover of these populations is not fully defined. Here we report that effector/memory CD8+ T cells induced by MCMV can be paradoxically boosted following transient depletion of epitope specific CD8+ T cells. Treatment of MCMV‐infected mice with MHC‐Class I‐saporin tetramers led to partial (80–90%) depletion of epitope‐specific CD8+ T cells—rapidly followed by a rebound, leading to expansion and maintenance of up to 40% of total CD8+ T cells, with minimal changes in response to a control epitope (M45). These data indicate the tight balance between host and virus during persistent infection and the functional flexibility of the “inflated” CD8+ T cell responses during persistent infection.
Enzyme‐Catalyzed Kinetic Resolution of 2,2,2‐Trifluoro‐1‐(heteroaryl)ethanols: Experimental and Docking Studies
Authors: Kucher Olexandr V. , Kolodiazhnaya Anastasiya O. , Smolii Oleg B. , Prisuazhnyk Dmytro V. , Tolmacheva Katerina A. , Zaporozhets Olga A. , Moroz Yurii S. , Mykhailiuk Pavel K. , Tolmachev Andrey A.
Published: October 2014

A convenient approach towards enantiopure (R) and (S) isomers of 2,2,2‐trifluoro‐1‐(heteroaryl)ethanols was developed. The enzyme‐catalyzed kinetic resolution of the corresponding racemic mixtures was achieved by using a two‐step protocol that involved an acylation and a hydrolysis step in the presence of Burkholderia cepacia and CAL‐B lipase (Candida antarctica lipase B), respectively. Fourteen compounds were resolved on a multigram scale by using this approach. The observed enantioselectivities correlated well with the results of molecular docking experiments.
DNA Recognition with Polycyclic‐Aromatic‐Hydrocarbon‐Presenting Calixarene Conjugates
Authors: Rescifina Antonio , Zagni Chiara , Mineo Placido G. , Giofrè Salvatore V. , Chiacchio Ugo , Tommasone Stefano , Talotta Carmen , Gaeta Carmine , Neri Placido
Published: October 2014

New calix[4]arene conjugates that present polycyclic aromatic hydrocarbons (PAHs) at their exo rims have been synthesized by esterification of a cone‐shaped calix[4]arenedicarboxylic acid with trans‐ or cis‐pyrenylisoxazolidinyl alcohols prepared by a 1,3‐dipolar cycloaddition methodology. The in vitro cytotoxic activities of all compounds were evaluated with three different human tumor cell lines, and the most potent one reached an IC50 of 95 nM. The different biological activities of the synthesized compounds were explained by docking and circular dichroism studies, which evidenced their intercalating abilities from the DNA minor groove.
Nickel‐Catalyzed Decarboxylative Arylation of Heteroarenes through sp2 C–H Functionalization
Authors: Yang Ke , Wang Peng , Zhang Cheng , Kadi Adnan A. , Fun Hoong‐Kun , Zhang Yan , Lu Hongjian
Published: October 2014

The direct decarboxylative arylation of hetereoarenes with benzoic acids through a nickel‐catalyzed sp2 C–H functionalization process was developed. This process provides the first examples of decarboxylative cross‐coupling reactions with aromatic acids through nickel catalysis and tolerates a variety of functional groups. Moreover, this method provides efficient access to 2‐aryl‐substituted azoles, an important structural unit in natural products, medicinal compounds, and functional materials.
Electrochemical Characterization of Carbon and Weathering Steels Corrosion Products to Determine the Protective Ability Using Carbon Paste Electrode (CPE)
Authors: Dhaiveegan P. , Elangovan N. , Nishimura T. , Rajendran N.
Published: October 2014

The electrochemistry of the corrosion products formed from carbon and weathering steel during four years of atmospheric exposure were investigated using a carbon paste electrode (CPE) by cyclic and square wave voltammetry. The iron rust products with crystalline nature were identified from their standard formal potential. The corrosion protection ability of the rust layers were determined by polarization and electrochemical impedance spectroscopy studies using CPE. ATR‐FTIR, SEM and XRD studies were employed to identify the composition and morphology of the corrosion products which supports SWV results. Results showed that the weathering steel has higher corrosion resistance than the carbon steel.
Measuring the Electrode Kinetics of Surface Confined Electrode Reactions at a Constant Scan Rate
Authors: Guziejewski Dariusz , Mirceski Valentin , Jadresko Dijana
Published: October 2014

The kinetics of surface confined electrode reactions of alizarin, vitamin B12, and vitamin K2 is measured with square‐wave voltammetry over a wide pH interval, by applying the recent methodology for kinetic analysis at a constant scan rate [V. Mirceski, D. Guziejewski, K. Lisichkov, Electrochim. Acta­ 2013, 114, 667–673]. The reliability and the simplicity of the recent methodology is confirmed. The methodology requires analysis of the peak potential separation of the forward and backward component of the response as a function of the pulse height (SW amplitude), for a given frequency (i.e. constant scan rate) of the potential modulation.
A spatial capture‐recapture model for territorial species
Authors: Reich B. J. , Gardner B.
Published: October 2014

Advances in field techniques have lead to an increase in spatially referenced capture–recapture data to estimate a species' population size as well as other demographic parameters and patterns of space usage. Statistical models for these data have assumed that the number of individuals in the population and their spatial locations follow a homogeneous Poisson point process model, which implies that the individuals are uniformly and independently distributed over the spatial domain of interest. In many applications, there is reason to question independence, for example, when species display territorial behavior. In this paper, we propose a new statistical model, which allows for dependence between locations to account for avoidance or territorial behavior. We show via a simulation study that accounting for this can improve population size estimates. The method is illustrated using a case study of small mammal trapping data to estimate avoidance and population density of adult female field voles (Microtus agrestis) in Northern England. Copyright © 2014 John Wiley & Sons, Ltd.
Is Non‐suicidal Self‐injury Related to Impulsivity in Anorexia Nervosa? Results from Self‐report and Performance‐based Tasks
Authors: Claes Laurence , Fagundo Ana B. , Jiménez‐Murcia Susana , Agüera Zaida , Giner‐Bartolome Cristina , Granero Roser , Sánchez Isabel , Riesco Nadine , Menchón Jose Manuel , Tarrega Salomé , Fernandez‐Aranda Fernando
Published: October 2014

The present study investigates the association between non‐suicidal self‐injury (NSSI) and impulsivity in anorexia nervosa (AN) patients by means of self‐report and behavioural tasks. In total, 60 female AN patients were included in the study, filled out the Barratt Impulsiveness Scale‐11 (BIS‐11) and performed three performance‐based tasks to assess different facets of impulsivity. Overall, 30% of the AN patients engaged in at least one form of NSSI during their lifetime. AN patients with and without NSSI did not significantly differ on the BIS‐11 impulsiveness scale. On the performance‐based measures, few differences emerged between AN patients with and without NSSI. Patients with NSSI showed more perseverations and perseveration errors (p < .05). The associations between self‐report and performance‐based measures were rather low, except for the association between the BIS‐11 and Wisconsin Card Sorting Task perseveration responses and errors (correlations |r| range between .32 and .42). The implications for theory and treatment of AN patients with and without NSSI will be discussed. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association.
Sea stack formation and the role of abrasion on beach‐mantled headlands
Authors: Limber Patrick W. , Murray A. Brad
Published: October 2014

Sea stacks are common and striking coastal landforms, but few details are known about how, how quickly, and under what conditions they form. We present numerical and analytical models of sea stack formation due to preferential erosion along a pre‐existing headland to address these basic questions. On sediment‐rich rocky coasts, as sea cliffs erode and retreat, they produce beach sediment that is distributed by alongshore sediment transport and controls future sea cliff retreat rates. Depending on their width, beaches can encourage or discourage sea cliff erosion by acting either as an abrasive tool or a protective cover that dissipates wave energy seaward of the cliff. Along the flanks of rocky headlands where pocket beaches are often curved and narrow due to wave field variability, abrasion can accelerate alongshore‐directed sea cliff erosion. Eventually, abrasion‐induced preferential erosion can cut a channel through a headland, separating it from the mainland to become a sea stack. Under a symmetrical wave climate (i.e. equal influence of waves approaching the coastline from the right and from the left), numerical and analytical model results suggest that sea stack formation time and plan‐view size are proportional to preferential erosion intensity (caused by, for example, abrasion and/or local rock weakness from joints, faults, or fractures) and initial headland aspect ratio, and that sea stack formation is discouraged when the sediment input from sea cliff retreat is too high (i.e. sea cliffs retreat quickly or are sand‐rich). When initial headland aspect ratio is too small, and the headland is ‘rounded’ (much wider in the alongshore direction at its base than at its seaward apex), the headland is less conducive to sea stack formation. On top of these geomorphic and morphologic controls, a highly asymmetrical wave climate decreases sea stack size and discourages stack formation through rock–sediment interactions. Copyright © 2014 John Wiley & Sons, Ltd.
Applications and implications of neurochemical biomarkers in environmental toxicology
Authors: Basu Niladri
Published: October 2014

Thousands of environmental contaminants have neurotoxic properties, but their ecological risk is poorly characterized. Contaminant-associated disruptions to animal behavior and reproduction, both of which are regulated by the nervous system, provide decision makers with compelling evidence of harm, but such apical endpoints are of limited predictive or harm-preventative value. Neurochemical biomarkers, which may be used to indicate subtle changes at the subcellular level, may help overcome these limitations. Neurochemical biomarkers have been used for decades in the human health sciences and are now gaining increased attention in the environmental realm. In the present review, the applications and implications of neurochemical biomarkers to the field of ecotoxicology are discussed. The review provides a brief introduction to neurochemistry, covers neurochemical-based adverse outcome pathways, discusses pertinent strengths and limitations of neurochemical biomarkers, and provides selected examples across invertebrate and vertebrate taxa (worms, bivalves, fish, terrestrial and marine mammals, and birds) to document contaminant-associated neurochemical disruption. With continued research and development, neurochemical biomarkers may increase understanding of the mechanisms that underlie injury to ecological organisms, complement other measures of neurological health, and be integrated into risk assessment practices. Environ Toxicol Chem 2015;34:22–29. © 2014 SETAC
Amyloid imaging with [18F]florbetapir in geriatric depression: early‐onset versus late‐onset
Authors: Tateno Amane , Sakayori Takeshi , Higuchi Makoto , Suhara Tetsuya , Ishihara Keiichi , Kumita Shinichiro , Suzuki Hidenori , Okubo Yoshiro
Published: October 2014

Background

We examined patients with mild cognitive impairment (MCI) with a history of geriatric depression (GD) and healthy controls (HC) to evaluate the effect of beta‐amyloid (Aβ) pathology on the pathology of GD by using [18F]florbetapir PET.

Methods

Thirty‐three elderly patients (76.7 ± 4.2 years) and 22 healthy controls (HC; 72.0 ± 4.5 years, average ± SD) were examined by [18F]florbetapir positron emission tomography (PET) to quantify the standard uptake value ratio (SUVR) as the degree of amyloid accumulation, by MRI to determine the degree of atrophy, by Mini‐Mental State Examination for cognitive functions, and by Geriatric Depression Scale for the severity of depression, and by Clinical Dementia Rating for activity of daily living (ADL). The cut‐off value of 1.08 for SUVR was defined as Aβ‐positive.

Results

Of the patients and HC, 39.4% and 27.3%, respectively, were beta‐amyloid‐positive. The onset age of GD was significantly correlated with SUVR (r = 0.44, p < 0.01). Compared to patients without Aβ (GD‐Aβ), patients with Aβ (GD + Aβ) did not differ in terms of age, cognitive function, severity of depression and ADL, and brain atrophy. GD + Aβ had significantly older average ± SD age at onset of GD (73.6 ± 7.1 versus 58.7 ± 17.8, p < 0.01) and significantly shorter average ± SD time between onset of GD and PET scan day (3.1 ± 5.2 years versus 18.1 ± 18.6 years, p < 0.001) than GD‐Aβ.

Conclusions

Our results showed that the rate of Aβ positivity was higher in late‐onset GD and that onset‐age was associated with SUVR, suggesting that the later the onset of GD, the more Aβ pathology affected its onset. Copyright © 2014 John Wiley & Sons, Ltd.
The effects of antidepressant treatment on resting‐state functional brain networks in patients with major depressive disorder
Authors: Wang Li , Xia Mingrui , Li Ke , Zeng Yawei , Su Yunai , Dai Wenji , Zhang Qinge , Jin Zhen , Mitchell Philip B. , Yu Xin , He Yong , Si Tianmei
Published: October 2014

Although most knowledge regarding antidepressant effects is at the receptor level, the neurophysiological correlates of these neurochemical changes remain poorly understood. Such an understanding could benefit from elucidation of antidepressant effects at the level of neural circuits, which would be crucial in identifying biomarkers for monitoring treatment efficacy of antidepressants. In this study, we recruited 20 first‐episode drug‐naive major depressive disorder (MDD) patients and performed resting‐state functional magnetic resonance imaging (MRI) scans before and after 8 weeks of treatment with a selective serotonin reuptake inhibitor—escitalopram. Twenty healthy controls (HCs) were also scanned twice with an 8‐week interval. Whole‐brain connectivity was analyzed using a graph‐theory approach—functional connectivity strength (FCS). The analysis of covariance of FCS was used to determine treatment‐related changes. We observed significant group‐by‐time interaction on FCS in the bilateral dorsomedial prefrontal cortex and bilateral hippocampi. Post hoc analyses revealed that the FCS values in the bilateral dorsomedial prefrontal cortex were significantly higher in the MDD patients compared to HCs at baseline and were significantly reduced after treatment; conversely, the FCS values in the bilateral hippocampi were significantly lower in the patients at baseline and were significantly increased after treatment. Importantly, FCS reduction in the dorsomedial prefrontal cortex was significantly correlated with symptomatic improvement. Together, these findings provided evidence that this commonly used antidepressant can selectively modulate the intrinsic network connectivity associated with the medial prefrontal‐limbic system, thus significantly adding to our understanding of antidepressant effects at a circuit level and suggesting potential imaging‐based biomarkers for treatment evaluation in MDD. Hum Brain Mapp 36:768–778, 2015. © 2014 Wiley Periodicals, Inc.
Use of inpatient palliative care services in patients with metastatic incurable head and neck cancer
Authors: Mulvey Carolyn L. , Smith Thomas J. , Gourin Christine G.
Published: October 2014

Background

Substantial health care resources are used on aggressive end‐of‐life care, despite an increasing recognition that palliative care improves quality of life and reduces health care costs. We examined the incidence of palliative care encounters in in‐patients with incurable head and neck cancer and associations with in‐hospital mortality, length of hospitalization, and costs.

Methods

Data from the Nationwide Inpatient Sample (NIS) for 80,514 head and neck cancer patients with distant metastatic disease in 2001 to 2010 was analyzed using cross‐tabulations and multivariate regressions.

Results

Palliative care encounters occurred in 4029 cases (5%) and were significantly associated with age ≥80 years, female sex, self‐pay payor status, and prior radiation. Palliative care was significantly associated with increased in‐hospital mortality and reduced hospital‐related costs.

Conclusion

Inpatient palliative care consultation in terminal head and neck cancer is associated with reduced hospital‐related costs, but appears to be underutilized and restricted to the elderly, uninsured, and patients with an increased risk of mortality. © 2015 Wiley Periodicals, Inc. Head Neck 38: 355–363, 2016
Women Managers’ Careers in China: Theorizing the Influence of Gender and Collectivism
Authors: Woodhams Carol , Xian Huiping , Lupton Ben
Published: October 2014

This article is concerned with developing an understanding of the careers of women managers in China. Existing literature suggests that while women in China are comparatively well represented in management roles, they face distinctive pressures and barriers to their progress arising from entrenched patriarchal and collectivist aspects of the Chinese cultural tradition. However, little is known about how these aspects impact on women's orientations towards their careers and to what extent influential Western career theories are adequate in interpreting their experience. Drawing on interviews with 20 women managers in China, the article interprets women's orientations towards their careers in relation to their adherence to traditional gender roles and collectivist values. Using this framework, a fourfold taxonomy is developed which identifies “conformist,” “revolutionary,” “soloist,” and “dissident” orientations. The article suggests that Western career theories fail to capture the collective dimension, and thus do not account fully for the range of experience and orientations of Chinese women managers that are captured in the taxonomy. Implications, both practical and theoretical, are discussed. Recommendations are also made as to how management and career development policies might be developed in organizations in China in order to address the diverse needs and preferences of women managers. © 2014 Wiley Periodicals, Inc.
A case‐control study to assess the impact of mammographic density on breast cancer risk in women aged 40–49 at intermediate familial risk
Authors: Assi Valentina , Massat Nathalie J. , Thomas Susan , MacKay James , Warwick Jane , Kataoka Masako , Warsi Iqbal , Brentnall Adam , Warren Ruth , Duffy Stephen W.
Published: October 2014

Mammographic density is a strong risk factor for breast cancer, but its potential application in risk management is not clear, partly due to uncertainties about its interaction with other breast cancer risk factors. We aimed to quantify the impact of mammographic density on breast cancer risk in women aged 40–49 at intermediate familial risk of breast cancer (average lifetime risk of 23%), in particular in premenopausal women, and to investigate its relationship with other breast cancer risk factors in this population. We present the results from a case‐control study nested with the FH01 cohort study of 6,710 women mostly aged 40–49 at intermediate familial risk of breast cancer. One hundred and three cases of breast cancer were age‐matched to one or two controls. Density was measured by semiautomated interactive thresholding. Absolute density, but not percent density, was a significant risk factor for breast cancer in this population after adjusting for area of nondense tissue (OR per 10 cm2 = 1.07, 95% CI 1.00–1.15, p = 0.04). The effect was stronger in premenopausal women, who made up the majority of the study population. Absolute density remained a significant predictor of breast cancer risk after adjusting for age at menarche, age at first live birth, parity, past or present hormone replacement therapy, and the Tyrer‐Cuzick 10‐year relative risk estimate of breast cancer. Absolute density can improve breast cancer risk stratification and delineation of high‐risk groups alongside the Tyrer‐Cuzick 10‐year relative risk estimate.
Why post‐progression survival and post‐relapse survival are not appropriate measures of efficacy in cancer randomized clinical trials
Authors: García‐Albéniz Xabier , Maurel Joan , Hernán Miguel A.
Published: October 2014

Comparisons of post‐relapse survival (PRS) and post‐progression survival have been used to measure efficacy in some cancer clinical trials. These comparisons are an attempt to account for second‐line therapies and to identify benefits that do not translate in longer overall survival. However, the use of PRS comparisons can be misleading (either a longer or shorter PRS may indicate a benefit, depending on the circumstances) and can result in biased estimates (because of selection). Here, we describe the problems surrounding PRS comparisons and propose alternative approaches to deal with non‐randomized therapies administered after progression to the experimental treatment.
Biomineralized hydroxyapatite nanoclay composite scaffolds with polycaprolactone for stem cell‐based bone tissue engineering
Authors: Ambre Avinash H. , Katti Dinesh R. , Katti Kalpana S.
Published: October 2014

Nanoclay modified with unnatural amino acid was used to design a nanoclay‐hydroxyapatite (HAP) hybrid by mineralizing HAP in the nanoclay galleries mimicking biomineralization. This hybrid (in situ HAPclay) was used to fabricate polycaprolactone (PCL)/in situ HAPclay films and scaffolds for bone regeneration. Cell culture assays and imaging were used to study interactions between human mesenchymal stem cells (hMSCs) and PCL/in situ HAPclay composites (films and scaffolds). SEM imaging indicated MSC attachment, formation of mineralized extracellular (ECM) on PCL/in situ HAPclay films, and infiltration of MSCs to the interior of PCL/in situ HAPclay scaffolds. Mineralized ECM was formed by MSCs without use of osteogenic supplements. AFM imaging performed on this in vitro generated mineralized ECM on PCL/in situ HAPclay films revealed presence of components (collagen and mineral) of hierarchical organization reminiscent of natural bone. Cellular events observed during two‐stage seeding experiments on PCL/in situ HAPclay films indicated similarities with events occurring during in vivo bone formation. PCL/in situ HAPclay films showed significantly increased (100–595% increase in elastic moduli) nanomechanical properties and PCL/in situ HAPclay scaffolds showed increased degradation. This work puts forth PCL/in situ HAPclay composites as viable biomaterials for bone tissue engineering. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 103A: 2077–2101, 2015.
VLookups for Management Accountants Using Two Criteria
Authors: Fuller Harlan J.
Published: October 2014

Excel VLookups can be useful for management and cost accountants in many ways. This article gives great practical examples of their use.
Vitamin D Receptor and RXR in the Post‐Genomic Era
Authors: Long Mark D. , Sucheston‐Campbell Lara E. , Campbell Moray J.
Published: October 2014

Following the elucidation of the human genome and components of the epigenome, it is timely to revisit what is known of vitamin D receptor (VDR) function. Early transcriptomic studies using microarray approaches focused on the protein coding mRNA that were regulated by the VDR, usually following treatment with ligand. These studies quickly established the approximate size and surprising diversity of the VDR transcriptome, revealing it to be highly heterogenous and cell type and time dependent. Investigators also considered VDR regulation of non‐protein coding RNA and again, cell and time dependency was observed. Attempts to integrate mRNA and miRNA regulation patterns are beginning to reveal patterns of co‐regulation and interaction that allow for greater control of mRNA expression, and the capacity to govern more complex cellular events. Alternative splicing in the trasncriptome has emerged as a critical process in transcriptional control and there is evidence of the VDR interacting with components of the splicesome. ChIP‐Seq approaches have proved to be pivotal to reveal the diversity of the VDR binding choices across cell types and following treatment, and have revealed that the majority of these are non‐canonical in nature. The underlying causes driving the diversity of VDR binding choices remain enigmatic. Finally, genetic variation has emerged as important to impact the transcription factor affinity towards genomic binding sites, and recently the impact of this on VDR function has begun to be considered. J. Cell. Physiol. 230: 758–766, 2015. © 2014 Wiley Periodicals, Inc.