bluuebunny/crossref_metadata_2025 huggingface dataset:
Neuroendocrine Tumors of the Pancreas: Molecular Pathogenesis and Perspectives on Targeted Therapies
Authors: Igor V. Maev  , Dmitry N. Andreev  , Yuriy A. Kucheryavyy  , Diana T. Dicheva
Published: August 2014

Pancreatic neuroendocrine tumors (PNETs) are a heterogeneous group of neoplasms that are the second most common among pancreatic neoplasms. Treatment of PNETs appears to be quite difficult because diagnosis in many patients occurs only at the latest stage when distant metastases are recognized. Therefore, treatment with drugs targeting PNET oncogenesis is a promising strategy in such patients. In this work, we review the present knowledge on the molecular nature of PNETs, and the genetic basis of PNET-associated hereditary syndromes, including multiple endocrine neoplasia type I, von Hippel-Lindau disease, neurofibromatosis type I, and tuberous sclerosis. In addition, the results of phase III, randomized, placebo-controlled trials of the efficacy of everolimus and sunitinib for treatment of extensive non-resectable PNETs are reviewed.
Sildenafil Enhances the Anticancer Activity of Paclitaxel in an ABCB1-Mediated Multidrug Resistance Xenograft Mouse Model
Authors: Kamlesh Sodani  , Amit K. Tiwari  , Chun-Ling Dai  , Alaa H. Abuznait  , Atish Patel  , Zhi-Jie Xiao  , Charles R. Ashby  , Amal Kaddoumi  , Li-Wu Fu  , Zhe-Sheng Chen
Published: August 2014

The overexpression of ATP-binding cassette (ABC) transporters can produce multidrug resistance (MDR) in cancer cells. Previous in vitro studies from our group reported that sildenafil significantly inhibits the efflux function of the ABCB1/P-glycoprotein transporter in vitro. This investigation examined the effect of sildenafil on the ABCB1 transporter-mediated MDR in vivo. A nude mouse ABCB1 overexpressing-xenograft model was used to examine the effect of sildenafil in vivo. The concentration of paclitaxel in tumors and plasma was analyzed using high performance liquid chromatography (HPLC). Sildenafil attenuated tumor growth synergistically, and this occurred without significant weight loss or other overt phenotypic changes. The action of sildenafil can be attributed to the inhibition of the ABCB1-mediated drug efflux, thereby increasing the concentration of paclitaxel in ABCB1-overexpressing tumors. The potentiation of the pharmacologic action of paclitaxel by sildenafil suggests that it may be useful in treating cancers that overexpress the ABCB1 transporter.
Human premotor areas parse sequences into their spatial and temporal features
Authors: Kornysheva Katja , Diedrichsen Jörn
Published: August 2014

Skilled performance is characterized by precise and flexible control of movement sequences in space and time. Recent theories suggest that integrated spatio-temporal trajectories are generated by intrinsic dynamics of motor and premotor networks. This contrasts with behavioural advantages that emerge when a trained spatial or temporal feature of sequences is transferred to a new spatio-temporal combination arguing for independent neural representations of these sequence features. We used a new fMRI pattern classification approach to identify brain regions with independent vs integrated representations. A distinct regional dissociation within motor areas was revealed: whereas only the contralateral primary motor cortex exhibited unique patterns for each spatio-temporal sequence combination, bilateral premotor areas represented spatial and temporal features independently of each other. These findings advocate a unique function of higher motor areas for flexible recombination and efficient encoding of complex motor behaviours.
Direct measurement of the mechanical work during translocation by the ribosome
Authors: Liu Tingting , Kaplan Ariel , Alexander Lisa , Yan Shannon , Wen Jin-Der , Lancaster Laura , Wickersham Charles E , Fredrick Kurt , Noller Harry , Tinoco Ignacio , Bustamante Carlos J
Published: August 2014

A detailed understanding of tRNA/mRNA translocation requires measurement of the forces generated by the ribosome during this movement. Such measurements have so far remained elusive and, thus, little is known about the relation between force and translocation and how this reflects on its mechanism and regulation. Here, we address these questions using optical tweezers to follow translation by individual ribosomes along single mRNA molecules, against an applied force. We find that translocation rates depend exponentially on the force, with a characteristic distance close to the one-codon step, ruling out the existence of sub-steps and showing that the ribosome likely functions as a Brownian ratchet. We show that the ribosome generates ∼13 pN of force, barely sufficient to unwind the most stable structures in mRNAs, thus providing a basis for their regulatory role. Our assay opens the way to characterizing the ribosome's full mechano–chemical cycle.
A descriptor list for Giant Swamp Taro (Cyrtosperma merkusii) and its cultivars in the Federated States of Micronesia
Authors: Rao Shiwangni , Taylor Mary , Jokhan Anjeela
Published: August 2014

Atoll islands are the diversity hot spots for Cyrtosperma merkusii (giant swamp taro) and its traditional knowledge,

especially in the Federated States of Micronesia (FSM). In these atolls and islands the giant aroid is given high importance in the food, cultural and traditional systems. Despite this, a significant lack of knowledge and threat of salt water intrusion in the face of climate change exists for the aroid. To curb this issue a classification descriptor list using the taro descriptors (1999) and traditional knowledge of the FSM farmers was developed. The descriptor list was then employed to classify the many cultivars present in FSM. The list consisted of 37 morphological traits divided into plant habit leaves, petiole, inflorescence, root, corm, taste and special characteristics. Using this descriptor list 40 distinct FSM cultivars was classified, four of which were unknown to the locals namely PF1, Semesrao, Liha mwahu and Nah. The results of the classification provided some knowledge of the various cultivars and also showed that diversity did exist within the gene pool of the aroid. With further research and documentation the diversity that exist within the gene pool of the aroid can be explored and utilized to buffer the impacts of salt water intrusion, while conserving the aroid and building its knowledge base.
Penetration depth of diapycnal mixing generated by wind stress and flow over topography in the northwestern Pacific
Authors: Li Ying , Xu Yongsheng
Published: August 2014

The role of turbulent diapycnal mixing in the northwestern Pacific was estimated by employing a fine‐scale parameterization method based on 6756 high‐resolution CTD profiles spanning a period of 8 years from the Japan Oceanography Data Center (JODC) and the Kuroshio Extension System Study (KESS). The rate of turbulent mixing in the upper ocean within 300–1800 m depth displayed a distinct seasonal cycle, bearing a statistically significant correlation to wind‐induced near‐inertial energy flux (hereafter denoted by WNEF). Enhanced turbulent mixing was also found near the rough seafloor relative to that over smooth topography. Enhanced dissipation at surface and bottom was found to be able to penetrate the ocean interior up to 1800 m and 3300 m, respectively, with penetration depths varying with the WNEF and topographic roughness. Our study here provides evidence for the important role of near‐inertial energy input from wind stress and the influence of bottom topography in maintaining mixing in the ocean interior.
EarthCube Seeking Members for Standing Committees and Teams
Authors: Showstack Randy
Published: August 2014

EarthCube is looking for individuals from across the Earth sciences to become members of standing committees and teams that will be responsible for carrying out key functions for EarthCube and EarthCube governance, according to Lee Allison, EarthCube Test Enterprise Governance Project principal investigator.
Assessing the Vulnerability of Water Supply to Changing Streamflow Conditions
Authors: Nazemi Alireza (Ali) , Wheater Howard S.
Published: August 2014

Natural streamflows are major water supplies globally and are sensitive to climate change. This has serious implications for water resource management: While changes in climate perturb water availability, human activities are developed around certain streamflow characteristics, such as flow seasonality and volume. Therefore, any shifts in streamflow regime can greatly affect human livelihoods.
Winter weather around the North Atlantic can be predicted
Authors: Wendel JoAnna
Published: August 2014

The North Atlantic Oscillation (NAO), which cycles from high pressure near Iceland and low pressure near the Azores to opposite conditions, has a major influence on climate and weather conditions in the Atlantic basin. Variations in the NAO have significant implications for North American and European weather, driving intense or mild winters and affecting many industries.
Fast transport of resonant electrons in phase space due to nonlinear trapping by whistler waves
Authors: Artemyev A. V. , Vasiliev A. A. , Mourenas D. , Agapitov O. V. , Krasnoselskikh V. , Boscher D. , Rolland G.
Published: August 2014

We present an analytical, simplified formulation accounting for the fast transport of relativistic electrons in phase space due to wave‐particle resonant interactions in the inhomogeneous magnetic field of Earth's radiation belts. We show that the usual description of the evolution of the particle velocity distribution based on the Fokker‐Planck equation can be modified to incorporate nonlinear processes of wave‐particle interaction, including particle trapping. Such a modification consists in one additional operator describing fast particle jumps in phase space. The proposed, general approach is used to describe the acceleration of relativistic electrons by oblique whistler waves in the radiation belts. We demonstrate that for a wave power distribution with a hard enough power law tail such that η < 5/2, the efficiency of nonlinear acceleration could be more effective than the conventional quasi‐linear acceleration for 100 keV electrons.
Inversion for the physical parameters that control the source dynamics of the 2004 Parkfield earthquake
Authors: Twardzik C. , Das S. , Madariaga R.
Published: August 2014

A fully dynamic inversion for the earthquake source process, in which the geometry of the rupture area, the stress conditions, and frictional properties on the fault are obtained, is carried out by inverting displacement records for the 2004Mw6.0 Parkfield, California, earthquake. The rupture area of the earthquake is modeled using elliptical patches, and seismograms from 10 near‐field digital stations are used. Synthetic tests to investigate the performance of the inversion in retrieving the rupture process demonstrate that we can reliably recover the large‐scale features of the spatiotemporal distribution of slip. To investigate the stress conditions and frictional properties of the fault under which we produce a rupture model that fits the observed data, we explore the parameter space using a Monte Carlo method and find an optimal region where the source models fit the data well. The best fitting rupture process is shown to occur mainly within one horizontal elliptical region, 22 km long along strike and 4 km wide along depth. The seismic moment is 1.2 × 1018N m, and the stress drop over the ellipse is ∼4 MPa. The rupture speed, nearly constant during the entire rupture process, is ∼2.9 km/s. The dimensionless quantityκ(roughly the strain energy change per unit fault surface divided by the energy release rate), which includes information on the stress and frictional properties on the fault, is found to be ∼1.4 for the ellipse and strongly controls the rupture process along with the size of the initial circular patch that initiates the earthquake.
Differences in gravity wave drag between realistic oblique and assumed vertical propagation
Authors: Kalisch Silvio , Preusse Peter , Ern Manfred , Eckermann Stephen D. , Riese Martin
Published: August 2014

Gravity wave (GW) parametrizations for general circulation models (GCMs) restrict the propagation of GWs to the vertical direction. The influence of this vertical‐only propagation assumption on the distribution of GW drag (GWD) has not yet been investigated. Thus, we present results of two global GW ray tracing simulations, one with full three‐dimensional propagation (GWO) and a second one with vertical‐only propagation (GWV) of GWs for January and July 2008. The Gravity wave Regional Or Global RAy Tracer (GROGRAT) was used to perform these simulations with a global homogeneous and isotropic launch distribution. Both simulations, GWO and GWV, are analyzed with respect to GWD in the zonal and meridional direction. The location of zonal GWD maxima changes. GWO shows in comparison to GWV a poleward shift of zonal GWD in both seasons with increased GWD at the summer stratopause. The meridional GWD is much stronger in the GWO case, spatially correlated with the zonal drag, and is generally poleward directed. These features in zonal and meridional drag are consistent with a general prevalence of poleward propagation of GWs. Additional simulations suggest that this is due to the Coriolis effect as well as wind filtering around the tropopause, allowing more GWs to propagate into the middle atmosphere. We infer how GWs of different horizontal wavelengths and phase speeds cause the main differences in GWD in the middle atmosphere. A simple test for GCMs is proposed to assess the effects of the altered meridional drag on the general circulation and the interaction with planetary waves.
Boundary layer regulation in the southeast Atlantic cloud microphysics during the biomass burning season as seen by the A‐train satellite constellation
Authors: Painemal David , Kato Seiji , Minnis Patrick
Published: August 2014

Solar radiation absorption by biomass burning aerosols has a strong warming effect over the southeast Atlantic. Interactions between the overlying smoke aerosols and low‐level cloud microphysics and the subsequent albedo perturbation are, however, generally ignored in biomass burning radiative assessments. In this study, Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) are combined with Aqua satellite observations from Moderate Resolution Imaging Spectroradiometer (MODIS), Advanced Microwave Scanning Radiometer–EOS (AMSR‐E), and Clouds and the Earth's Radiant Energy System (CERES) to assess the effect of variations in the boundary layer height and the separation distance between the cloud and aerosol layers on the cloud microphysics. The merged data analyzed at a daily temporal resolution suggest that overlying smoke aerosols modify cloud properties by decreasing cloud droplet size despite an increase in the cloud liquid water as boundary layer deepens, north of 5°S. These changes are controlled by the proximity of the aerosol layer to the cloud top rather than increases in the column aerosol load. The correlations are unlikely driven by meteorological factors, as three predictors of cloud variability, lower tropospheric stability, surface winds, and mixing ratio suggest that cloud effective radius, cloud top height, and liquid water path should correlate positively. Because cloud effective radius anticorrelates with cloud liquid water over the region with large microphysical changes—north of 5°S—the overall radiative consequence at the top of the atmosphere is a strong albedo susceptibility, equivalent to a 3% albedo increase due to a 10% decrease in cloud effective radius. This albedo enhancement partially offsets the aerosol solar absorption. Our analysis emphasizes the importance of accounting for the indirect effect of smoke aerosols in the cloud microphysics when estimating the radiative impact of the biomass burning at the top of the atmosphere.
Equatorial Pacific productivity changes near the Eocene‐Oligocene boundary
Authors: Moore T. C. , Wade Bridget S. , Westerhold Thomas , Erhardt Andrea M. , Coxall Helen K. , Baldauf Jack , Wagner Meghan
Published: August 2014

There is general agreement that productivity in high latitudes increased in the late Eocene and remained high in the early Oligocene. Evidence for both increased and decreased productivity across the Eocene‐Oligocene transition (EOT) in the tropics has been presented, usually based on only one paleoproductivity proxy and often in sites with incomplete recovery of the EOT itself. A complete record of the Eocene‐Oligocene transition was obtained at three drill sites in the eastern equatorial Pacific Ocean (ODP Site 1218 and IODP Sites U1333 and U1334). Four paleoproductivity proxies that have been examined at these sites, together with carbon and oxygen isotope measurements on early Oligocene planktonic foraminifera, give evidence of ecologic and oceanographic change across this climatically important boundary. Export productivity dropped sharply in the basal Oligocene (~33.7 Ma) and only recovered several hundred thousand years later; however, overall paleoproductivity in the early Oligocene never reached the average levels found in the late Eocene and in more modern times. Changes in the isotopic gradients between deep‐ and shallow‐living planktonic foraminifera suggest a gradual shoaling of the thermocline through the early Oligocene that, on average, affected accumulation rates of barite, benthic foraminifera, and opal, as well as diatom abundance near 33.5 Ma. An interval with abundant large diatoms beginning at 33.3 Ma suggests an intermediate thermocline depth, which was followed by further shoaling, a dominance of smaller diatoms, and an increase in average primary productivity as estimated from accumulation rates of benthic foraminifera.
Ganoderic acid D
Authors: Lin Lishan
Published: August 2014

Ganoderic acid D is a major active component of
Ganoderma lucidum
. It inhibits the growth of numerous cancer cell lines. Metabolism of ganoderic acid D was investigated in rats after an oral dose. Major metabolic pathways included keto reduction, alcohol oxidation, dehydrogenation, hydroxylation, and sulfate and glucuronide conjugations. A total of 25 metabolites were detected in rat bile, derived from the combination of the above metabolic reactions.
Milnacipran
Authors: Zhou Xin
Published: August 2014

Milnacipran is a serotonin–norepinephrine reuptake inhibitor used to treat major depressive disorder and fibromyalgia. Metabolism and excretion of [
14
C]‐milnacipran were studied in healthy male subjects after a single oral 100‐mg dose. Approximately 93% of the total radioactivity was excreted in the urine. Unchanged milnacipran (55% of the dose) was the most abundant material found in urine. Primary metabolic reactions included N‐dealkylation and N‐formylation followed by glucuronide formation. Major metabolites were milnacipran carbamoyl
O
‐glucuronide and
N
‐desethyl milnacipran, accounting 19% and 8% of the total radioactivity, respectively.
‘This Is the Person You Selected’: Eyewitnesses' Blindness for Their Own Facial Recognition Decisions
Authors: Sagana Anna , Sauerland Melanie , Merckelbach Harald
Published: August 2014

The aim of the current research was to identify conditions under which choice blindness in facial recognition decisions occurs. In five experiments, participants watched four mock‐crime videos and made choices that were either evaluative (Experiment 1) or absolute in nature (Experiments 2a–c and 3). When participants were subsequently asked to motivate their choice, they were sometimes presented with choices they had not made. For evaluative decisions, concurrent (27%) and retrospective blindness rates (21%) were relatively low compared with previous studies. For absolute decisions, choice‐blindness rates varied, depending on when exposure to the manipulated outcome took place (immediate: concurrent 32–35%, retrospective 0–6% [Experiments 2a–c]; 48 hours' delay: concurrent 68%, retrospective 39% [Experiment 3]). We argue that blindness for facial recognition decisions is more likely for evaluative decisions and for longer intervals between decision and manipulation and also for conditions of increased task complexity, which we interpret in terms of ambiguity. Copyright © 2014 John Wiley & Sons, Ltd.
Exposure to Product Placement in Text Can Influence Consumer Judgments
Authors: Storm Benjamin C. , Stoller Eve
Published: August 2014

Five experiments explored the consequences of exposure to product placement in text. In each experiment, participants read three short stories containing the names of several brand‐name products. When given a surprise judgment task asking them to rate their likelihood of purchasing a number of brands—some of which were placed and some of which were not placed—participants rated placed brands significantly higher than non‐placed brands. This effect of product placement was observed even when participants were warned about product placement prior to reading the stories, and even when participants reported having a negative opinion about product placement as a form of advertisement. Under some conditions, however, the effect did interact with brand familiarity, such that judgments of familiar brands were affected less by product placement than were judgments of unfamiliar brands. Copyright © 2014 John Wiley & Sons, Ltd.
A Designed Conformational Shift To Control Protein Binding Specificity
Authors: Michielssens Servaas , Peters Jan Henning , Ban David , Pratihar Supriya , Seeliger Daniel , Sharma Monika , Giller Karin , Sabo Thomas Michael , Becker Stefan , Lee Donghan , Griesinger Christian , de Groot Bert L.
Published: August 2014

In a conformational selection scenario, manipulating the populations of binding‐competent states should be expected to affect protein binding. We demonstrate how in silico designed point mutations within the core of ubiquitin, remote from the binding interface, change the binding specificity by shifting the conformational equilibrium of the ground‐state ensemble between open and closed substates that have a similar population in the wild‐type protein. Binding affinities determined by NMR titration experiments agree with the predictions, thereby showing that, indeed, a shift in the conformational equilibrium enables us to alter ubiquitin’s binding specificity and hence its function. Thus, we present a novel route towards designing specific binding by a conformational shift through exploiting the fact that conformational selection depends on the concentration of binding‐competent substates.
Morphology development, melt linear viscoelastic properties and crystallinity of polylactide/polyethylene/organoclay blend nanocomposites
Authors: Abdolrasouli Mehdi Haji , Nazockdast Hossein , Sadeghi Gity Mir Mohamad , Kaschta Joachim
Published: August 2014

Polylactide/polyethylene blends (PLA/PE) and their nanocomposites were prepared via the melt blending process. The effects of organoclay, compatibilizer (PE‐g‐MA), and PE content on morphology, linear viscoelastic properties of the melt and cold crystallization of the samples have been studied. The Palierne model is applied to predict the rheological behavior of unfilled blends. It implies that there is a quantitative agreement between model and experimental data for low PE content blend. From WAXD and the rheological behavior, it is shown that organoclay exhibits a higher extent of intercalation and dispersion in PLA/PE/organoclay nanocomposite than in PLA/organoclay nanocomposite. The DSC results present that the addition of compatibilizer into blend nanocomposite increases cold crystallization temperature of PLA by about 3°C. This can be explained by the role of compatibilizer in transfer of a part of organoclay from PLA matrix to droplets resulting in increase of PLA chain mobility and, therefore, slightly greater cold crystallization temperature. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41300.
Impact of High Ytterbium(III) Concentration in the Shell on Upconversion Luminescence of Core–Shell Nanocrystals
Authors: Lei Lei , Chen Daqin , Zhu Wenjuan , Xu Ju , Wang Yuansheng
Published: August 2014

After coating 20 Yb/2 Er:NaGdF4 core nanocrystals with a NaYbF4 shell, upconversion emission of the rare earth ions weakens. So far, the exact reason for this phenomenon is still unclear due to lack of the direct evidence. In this report, a core@shell@shell sandwich‐like structure is designed and fabricated to investigate this phenomenon. We find that high Yb3+ concentration in the shell has mainly two adverse impacts: it promotes not only the deleterious back energy transfer from Er3+ in the core to Yb3+ in the shell but also the energy transfer from Yb3+ in the core to Yb3+ in the shell. To obtain nanocrystals with high upconversion efficency, appropriate Yb3+ concentration should be introduced into the shell or the transition layer.
Maturation of biomass‐to‐biofuels conversion technology pathways for rapid expansion of biofuels production: a system dynamics perspective
Authors: Vimmerstedt Laura J. , Bush Brian W. , Hsu Dave D. , Inman Daniel , Peterson Steven O.
Published: August 2014

The Biomass Scenario Model (BSM) is a system‐dynamics simulation model intended to explore the potential for rapid expansion of the biofuels industry. The model is not predictive — it uses scenario assumptions based on various types of data to simulate industry development, emphasizing how incentives and technological learning‐by‐doing might accelerate industry growth. The BSM simulates major sectors of the biofuels industry, including feedstock production and logistics, conversion, distribution, and end uses, as well as interactions among sectors. The model represents conversion of biomass to biofuels as a set of technology pathways, each of which has allowable feedstocks, capital and operating costs, allowable products, and other defined characteristics. This study and the BSM address bioenergy modeling analytic needs that were identified in recent literature reviews. Simulations indicate that investments are most effective at expanding biofuels production through learning‐by‐doing when they are coordinated with respect to timing, pathway, and target sector within the biofuels industry. Effectiveness metrics include timing and magnitude of increased production, incentive cost and cost effectiveness, and avoidance of windfall profits. Investment costs and optimal investment targets have inherent risks and uncertainties, such as the relative value of investment in more‐mature versus less mature pathways. These can be explored through scenarios, but cannot be precisely predicted. Dynamic competition, including competition for cellulosic feedstocks and ethanol market shares, intensifies during times of rapid growth. Ethanol production increases rapidly, even up to Renewable Fuel Standards‐targeted volumes of biofuel, in simulations that allow higher blending proportions of ethanol in gasoline‐fueled vehicles. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Biofuels, Bioproducts, Biorefining published by John Wiley & Sons, Ltd on behalf of Society of Chemical Industry.
World's largest biofuel and pellet plants – geographic distribution, capacity share, and feedstock supply
Authors: Kuparinen Katja , Heinimö Jussi , Vakkilainen Esa
Published: August 2014

Biomass can be used for energy purposes by either combustion to heat and power or refining into solid and liquid biofuels. The majority of biomass is used for residential purposes in developing countries. Modern biomass use in industrialized countries is increasing, and more and more biomass is also traded to be used for energy purposes. The purpose of this paper is to locate the 15 largest ethanol, biodiesel, and wood pellet plants. Facilities generating heat, steam and electricity were left out. Secondly it is not generally known what share of biomass users are large plants. Also an effort is made to find out how much these large‐scale biomass refining plants use imported feedstock. For the most part, very large industrial processing facilities are found in a small number of countries. The largest ethanol mills are found almost exclusively in the United States, with one very large plant in the Netherlands. The distribution of biodiesel and wood pellet plants is more dispersed. The countries with the most large biodiesel plants include the USA, Brazil, Spain, and the Netherlands. The countries with the most very large wood pellet plants include the USA, Canada, Russia, and Germany. Torrefaction and pyrolysis technologies are still rarely used on industrial scale. Ethanol and wood pellet plants tend to be sourced from local feedstocks, while biodiesel plants are much more likely to use imported feedstocks or a mix of imports and local biomass. All of these fuels are increasingly traded through the international market. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd
Fluorescent dye ProteoStat to detect and discriminate intracellular amyloid‐like aggregates in Escherichia coli
Authors: Navarro Susanna , Ventura Salvador
Published: August 2014

The formation of amyloid aggregates is linked to the onset of an increasing number of human disorders. Thus, there is an increasing need for methodologies able to provide insights into protein deposition and its modulation. Many approaches exist to study amyloids in vitro, but the techniques available for the study of amyloid aggregation in cells are still limited and non‐specific. In this study we developed a methodology for the detection of amyloid‐like aggregates inside cells that discriminates these ordered assemblies from other intracellular aggregates. We chose bacteria as model system, since the inclusion bodies formed by amyloid proteins in the cytosol of bacteria resemble toxic amyloids both structurally and functionally. Using confocal microscopy, fluorescence spectroscopy, and flow cytometry, we show that the recently developed red fluorescent dye ProteoStat can detect the presence of intracellular amyloid‐like deposits in living bacterial cells with high specificity, even when the target proteins are expressed at low levels. This methodology allows quantitation of the intracellular amyloid content, shows the potential to replace in vitro screenings in the search for therapeutic anti‐amyloidogenic compounds, and might be useful for identifying conditions that prevent the aggregation of therapeutic recombinant proteins.
The Effects of Negative Images on Young People's Willingness to Help Elderly People
Authors: van Leeuwen Esther , Jongh Lennert
Published: August 2014

We examined the effect of confronting young people with an image depicting them as unhelpful on their willingness to help elderly people. As expected, helpfulness increased when this image reflected the elderly's view of young people but decreased when it reflected objective information. Copyright © 2014 John Wiley & Sons, Ltd.
Effects of Ultrasound and Microwaves on Selective Reduction: Catalyst Preparation and Reactions
Authors: Wu Zhilin , Borretto Emily , Medlock Jonathan , Bonrath Werner , Cravotto Giancarlo
Published: August 2014

The reduction of organic compounds through catalytic hydrogenation is an important transformation in organic chemistry, especially in the synthesis of fine chemicals, natural products, and pharmaceuticals. This review mainly focuses on the selective reduction of substrates with multiple functional groups. Literature from the last two decades has proved the pivotal role that ultrasound and microwaves can play not only in the preparation of environmentally friendly, efficient catalysts but also in their use in catalytic reactions. Owing to the specific selective activation of the solid catalyst surface, dielectric heating and acoustic cavitation may dramatically enhance the reaction rate and selectivity. A thorough literature survey was the first step in the MAPSYN project (EU 7th Framework Program) and has the goal of the industrial demonstration of selective hydrogenations intensified by microwaves and ultrasound. Both techniques are irreplaceable tools in heterogeneous catalysis and can be expected to bring even greater success in the near future as processes are scaled up with suitable flow reactors equipped with on‐line analytical monitoring.
Feasibility of a Co Oxygen Carrier for Chemical Looping Air Separation: Thermodynamics and Kinetics
Authors: Wang Kun , Yu Qingbo , Qin Qin , Duan Wenjun
Published: August 2014

Chemical looping air separation (CLAS) is based on the chemical looping principle: oxygen carriers release oxygen to carrier gas in a reduction reactor and absorb oxygen from air in an oxidation reactor. High oxygen transport capacity, high reactivity in reduction and oxidation reactions, and resistance to attrition and agglomeration are some of the criteria that feasible oxygen carrier materials should fulfill. Thermodynamic analysis was applied to prove the potential of Co3O4 as oxygen carrier. ZrO2 served as binder to improve the anti‐sintering property and reactivity. Kinetic experiments were performed to determine the reaction rate and conversion of the oxygen carrier. Stability and durability of the oxygen carrier were characterized before and after cyclic experiments. The Co/Zr oxygen carrier proved to be a suitable candidate for the CLAS process.
Using Coal Fly Ash and Wastewater for Microwave Synthesis of LTA Zeolite
Authors: Behin Jamshid , Bukhari Syed Salman , Dehnavi Vahid , Kazemian Hossein , Rohani Sohrab
Published: August 2014

The reuse of industrial wastes from a coal‐fired power plant and a plasma electrolytic oxidation process was attempted to realize a zero discharge. The batch composition was adjusted by adding sodium hydroxide and sodium aluminate. A single‐mode microwave oven equipped with reflux condenser was used for crystallization under atmospheric pressure. The synthesized samples were characterized by X‐ray diffraction, scanning electron microscopy, BET, thermogravimetric analysis, and cation‐exchange capacity (CEC) measurement. Analytical results indicated that Na‐A zeolite with a defined maximum crystallinity could be successfully synthesized by hydrothermal treatment of fly ash with wastewater. Due to the high CEC, the product can be applied for gas purification and soil remediation processes.
Mechanistic Studies of Gd3+‐Based MRI Contrast Agents for Zn2+ Detection: Towards Rational Design
Authors: Bonnet Célia S. , Caillé Fabien , Pallier Agnès , Morfin Jean‐François , Petoud Stéphane , Suzenet Franck , Tóth Éva
Published: August 2014

A series of novel pyridine‐based Gd3+ complexes have been prepared and studied as potential MRI contrast agents for Zn2+ detection. By independent assessment of molecular parameters affecting relaxivity, we could interpret the relaxivity changes observed upon Zn2+ binding in terms of variations of the rotational motion.
Enhanced Thermal Oxidation Stability of Reduced Graphene Oxide by Nitrogen Doping
Authors: Sandoval Stefania , Kumar Nitesh , Sundaresan A. , Rao C. N. R. , Fuertes Amparo , Tobias Gerard
Published: August 2014

Nitrogen‐doped reduced graphene oxide (N‐doped RGO) samples with a high level of doping, up to 13 wt. %, have been prepared by annealing graphene oxide under a flow of pure ammonia. The presence of nitrogen within the structure of RGO induces a remarkable increase in the thermal stability against oxidation by air. The thermal stability is closely related with the temperature of synthesis and the nitrogen content. The combustion reaction of nitrogen in different coordination environments (pyridinic, pyrrolic, and graphitic) is analyzed against a graphene fragment (undoped) from a thermodynamic point of view. In agreement with the experimental observations, the combustion of undoped graphene turns out to be more spontaneous than when nitrogen atoms are present.
Secondary malignant neoplasms among children, adolescents, and young adults with osteosarcoma
Authors: Lee Jean S. , DuBois Steven G. , Boscardin W. John , Wustrack Rosanna L. , Goldsby Robert E.
Published: August 2014

BACKGROUND

As patients with osteosarcoma become long‐term survivors, increasing attention has turned to the burden of late effects. The goal of the current study was to describe the incidence, characteristics, and outcomes of secondary malignant neoplasms (SMNs) in this population.

METHODS

Patients aged birth to 40 years at time of primary diagnosis with osteosarcoma and reported to the Surveillance, Epidemiology, and End Results (SEER) program between 1973 and 2010 were eligible for inclusion in the cohort. Competing risks methods were used to estimate the cumulative incidence of SMNs and potential risk factors for developing an SMN. Standardized incidence ratios (SIR) and overall survival after an SMN were estimated.

RESULTS

The SEER database included 3379 patients who were diagnosed with osteosarcoma as their first malignancy. Of these, 89 patients were diagnosed with an SMN. The cumulative incidence of any SMN was 2.1% (95% confidence interval [95% CI], 1.6%‐2.7%) at 10 years, 4.0% (95% CI, 3.1%‐5.1%) at 20 years, and 7.4% (95% CI, 5.6%‐9.5%) at 30 years. The median time from the primary diagnosis to an SMN diagnosis was 6.0 years. The SIR for SMNs for survivors of osteosarcoma compared with the general population was 1.6 (95% CI, 1.0‐2.5) for patients diagnosed with osteosarcoma from 1973 through 1985 and 4.7 (95% CI, 3.3‐6.4) for patients diagnosed with osteosarcoma from 1986 through 2010, with a 34‐fold increased risk of leukemia in this most recent era. The overall survival rate at 5 years for patients with SMNs after a diagnosis of osteosarcoma was 44.5%.

CONCLUSIONS

Survivors of osteosarcoma are at an increased risk of developing SMNs compared with the baseline population, with an increased risk noted in patients treated in the more recent era. Cancer 2014;120:3987–3993 © 2014 American Cancer Society.
Interobserver reproducibility and accuracy of p16/Ki‐67 dual‐stain cytology in cervical cancer screening
Authors: Wentzensen Nicolas , Fetterman Barbara , Tokugawa Diane , Schiffman Mark , Castle Philip E. , Wood Shannon N. , Stiemerling Eric , Poitras Nancy , Lorey Thomas , Kinney Walter
Published: August 2014

BACKGROUND

Dual‐stain cytology for p16 and Ki‐67 has been proposed as a biomarker in cervical cancer screening. The authors evaluated the reproducibility and accuracy of dual‐stain cytology among 10 newly trained evaluators.

METHODS

In total, 480 p16/Ki‐67–stained slides from human papillomavirus‐positive women were evaluated in masked fashion by 10 evaluators. None of the evaluators had previous experience with p16 or p16/Ki‐67 cytology. All participants underwent p16/Ki‐67 training and subsequent proficiency testing. Reproducibility of dual‐stain cytology was measured using the percentage agreement, individual and aggregate κ values, as well as McNemar statistics. Clinical performance for the detection of cervical intraepithelial neoplasia grade 2 or greater (CIN2+) was evaluated for each individual evaluator and for all evaluators combined compared with the reference evaluation by a cytotechnologist who had extensive experience with dual‐stain cytology.

RESULTS

The percentage agreement of individual evaluators with the reference evaluation ranged from 83% to 91%, and the κ values ranged from 0.65 to 0.81. The combined κ value was 0.71 for all evaluators and 0.73 for cytotechnologists. The average sensitivity and specificity for the detection of CIN2+ among novice evaluators was 82% and 64%, respectively; whereas the reference evaluation had 84% sensitivity and 63% specificity, respectively. Agreement on dual‐stain positivity increased with greater numbers of p16/Ki‐67–positive cells on the slides.

CONCLUSIONS

Good to excellent reproducibility of p16/Ki‐67 dual‐stain cytology was observed with almost identical clinical performance of novice evaluators compared with reference evaluations. The current findings suggest that p16/Ki‐67 dual‐stain evaluation can be implemented in routine cytology practice with limited training. Cancer (Cancer Cytopathol) 2014;122:914–920. © 2014 American Cancer Society.
Expression profile analysis of vulnerable CA1 pyramidal neurons in young–Middle‐Aged Ts65Dn mice
Authors: Alldred Melissa J. , Lee Sang Han , Petkova Eva , Ginsberg Stephen D.
Published: August 2014

Down syndrome (DS) is the most prevalent cause of intellectual disability (ID). Individuals with DS show a variety of cognitive deficits, most notably in hippocampal learning and memory, and display pathological hallmarks of Alzheimer's disease (AD), with neurodegeneration of cholinergic basal forebrain (CBF) neurons. Elucidation of the molecular and cellular underpinnings of neuropathology has been assessed via gene expression analysis in a relevant animal model, termed the Ts65Dn mouse. The Ts65Dn mouse is a segmental trisomy model of DS that mimics DS/AD pathology, notably age‐related cognitive dysfunction and degeneration of basal forebrain cholinergic neurons (BFCNs). To determine expression level changes, molecular fingerprinting of cornu ammonis 1 (CA1) pyramidal neurons was performed in adult (4–9 month‐old) Ts65Dn mice, at the initiation of BFCN degeneration. To quantitate transcriptomic changes during this early time period, laser capture microdissection (LCM), terminal continuation (TC) RNA amplification, custom‐designed microarray analysis, and subsequent validation of individual transcripts by qPCR and protein analysis via immunoblotting was performed. The results indicate significant alterations within CA1 pyramidal neurons of Ts65Dn mice compared with normal disomic (2N) littermates, notably in the downregulation of neurotrophins and their cognate neurotrophin receptors among other classes of transcripts relevant to neurodegeneration. The results of this single‐population gene expression analysis at the time of septohippocampal deficits in a trisomic mouse model shed light on a vulnerable circuit that may cause the AD‐like pathology invariably seen in DS that could help to identify mechanisms of degeneration, and provide novel gene targets for therapeutic interventions. J. Comp. Neurol. 523:61–74, 2015. © 2014 Wiley Periodicals, Inc.
Nuclear Magnetic Resonance Relaxivities: Investigations of Ultrahigh‐Spin Lanthanide Clusters from 10 MHz to 1.4 GHz
Authors: Machado Julyana R. , Baniodeh Amer , Powell Annie K. , Luy Burkhard , Krämer Steffen , Guthausen Gisela
Published: August 2014

Paramagnetic relaxation enhancement is often explored in magnetic resonance imaging in terms of contrast agents and in biomolecular nuclear magnetic resonance (NMR) spectroscopy for structure determination. New ultrahigh‐spin clusters are investigated with respect to their NMR relaxation properties. As their molecular size and therefore motional correlation times as well as their electronic properties differ significantly from those of conventional contrast agents, questions about a comprehensive characterization arise. The relaxivity was studied by field‐dependent longitudinal and transverse NMR relaxometry of aqueous solutions containing FeIII10DyIII10 ultrahigh‐spin clusters (spin ground state 100/2). The high‐field limit was extended to 32.9 T by using a 24 MW resistive magnet and an ultrahigh‐frequency NMR setup. Interesting relaxation dispersions were observed; the relaxivities increase up to the highest available fields, which indicates a complex interplay of electronic and molecular correlation times.
Seasonal and annual variation in transpiration of a dominant desert species, Haloxylon ammodendron, in Central Asia up‐scaled from sap flow measurement
Authors: Zheng Chaolei , Wang Quan
Published: August 2014

Transpiration in plants is a critical eco‐hydrological process linking plant–atmosphere interactions and is very important in the arid environment because the surface runoff is of no practical importance in terms of the hydrological budget. Investigations on transpiration in arid land species under natural conditions have not been comprehensive, however. We present here the long‐term transpiration of Haloxylon ammodendron, a dominant species growing at the southern edge of the Gurbantünggüt Desert, China, during the growing seasons from 2009 to 2011 using up‐scaled sap flow monitoring with the thermal dissipation probe method. The sap flux density averaged 1·86 m3 m−2 day−1 during the measurement period for 3 years, and the transpiration per day based on ground area (EC) ranged from 0·05 to 0·27 mm day−1 and averaged 0·14 mm day−1, lower than that of other species largely because of the extremely arid environment. The canopy stomatal conductance averaged 16·75 mmol m−2 s−1 and maintained a constant low value under high vapour pressure deficit, which is essential for maintaining low transpiration compared with other species. High seasonal variation in EC was exhibited because of the plant's response to environmental factors at seasonal scale. EC showed much less variability at annual scale, however, because of the constant balance between the evaporative demand of the atmosphere and plant factors. These results contribute to a better understanding of the plant's transpiration in arid land and its response and adaptation to climatic changes at annual and seasonal scales. Copyright © 2014 John Wiley & Sons, Ltd.
Stereoselective Synthesis of Enantiopure Cycloalkylglycines by 1,3‐Dipolar Cycloaddition of a Chiral Nitrone to Cycloalkenes
Authors: Abda Heithem , Aouadi Kaïss , Perrin Lionel , Msaddek Moncef , Praly Jean‐Pierre , Vidal Sébastien
Published: August 2014

The design of cyclic analogues of 4‐hydroxyisoleucine, a natural remedy used by type‐2 diabetic patients, can provide putative hypoglycemic drugs. To this end, the 1,3‐dipolar cycloaddition of a (–)‐menthone‐derived nitrone to cycloalkenes afforded isoxazolidines in high yields and with high stereoselectivity. The cycloadducts led to α‐amino lactones after a one‐pot cleavage of the N–O, amide, and N–C–N bonds. Subsequent base‐catalyzed hydrolysis provided enantiopure cycloalkylglycine derivatives in good overall yields (>40 %) in three simple synthetic steps from the menthone‐based chiral nitrone. The conformational analysis of these analogues by DFT calculations highlight some interesting features of the volume occupied by the cycloalkyl residues in comparison to that occupied by the natural 4‐hydroxyisoleucine.
Individual differences make a difference: On the use and the psychometric properties of difference scores in social psychology
Authors: Gollwitzer Mario , Christ Oliver , Lemmer Gunnar
Published: August 2014

Much social psychological research is concerned with the question whether and how behavior changes because of a “treatment” (e.g., a situation that triggers a psychological reaction). One easy way to investigate such changes would be to analyze intraindividual differences before (Time 1) and after the treatment (Time 2). Interestingly, many scholars refrain from using difference scores because they think they are inherently unreliable. However, the bad reputation of difference scores is, in many cases, unwarranted: difference scores can be sufficiently reliable when standard deviations differ between measurement occasions, and standard deviations are likely to differ between measurement occasions because of differential treatment effects (i.e., interindividual differences in responsiveness to a treatment) and/or “strong situation” treatments. In the present article, we will (1) summarize classic and current arguments regarding the reliability of difference scores, (2) discuss the use of residual change scores as an alternative to difference scores, and (3) argue that latent difference score models are a particularly useful tool that social psychologists should consider using more frequently. Copyright © 2014 John Wiley & Sons, Ltd.