bluuebunny/crossref_metadata_2025 huggingface dataset:
ChemInform Abstract: Chemoselective Synthesis of Enamino‐Coumarin Derivatives Identified as Potent Antitumor Agents.
Authors: Ibrahim Mona E. , Hamama Wafaa S. , Metwalli Asmaa E. , Zoorob Hanafi H.
Published: November 2016

Starting from 4‐aminocoumarin (I), various coumarine derivatives are synthesized by standard procedures.
ChemInform Abstract: Synthesis of Chiral Piperazines via Hydrogenation of Pyrazines Activated by Alkyl Halides.
Authors: Huang Wen‐Xue , Liu Lian‐Jin , Wu Bo , Feng Guang‐Shou , Wang Baomin , Zhou Yong‐Gui
Published: November 2016

Thorough adjustment of the hydrogen pressure and the ligands allows for the preparation of 3‐substituted, 3,5‐ as well as 2,3‐disubstituted pyrazines from the corresponding pyrazine salts.
ChemInform Abstract: One‐Pot Regio‐ and Stereoselective Synthesis of Tertiary Phosphine Chalcogenides with (E)‐N‐Ethenyl‐1,2‐dihydroquinoline Functionalities.
Authors: Gusarova Nina K. , Volkov Pavel A. , Ivanova Nina I. , Khrapova Kseniya O. , Albanov Alexander I. , Afonin Andrei V. , Borodina Tatyana N. , Trofimov Boris A.
Published: November 2016

The synthesis of the title compounds via three‐component reaction between secondary phosphine chalcogenides quinoline or isoquinoline and alkyl propiolates or acetylene dicarboxylate is reported.
ChemInform Abstract: New Compounds from the Roots and Stems of Trigonostemon lii and Their Cytotoxic Activities.
Authors: Liu Yong‐Qin , Di Ying‐Tong , Wang Yue‐Hu , Hao Xiao‐Jiang , Hu Xu‐Jia
Published: November 2016

A new carboline alkaloid, Trifiline D (I), and a new degraded diterpenoid, Trigoxyphin X (II), are isolated from the title plant.
ChemInform Abstract: Nanoscale Chirality in Metal and Semiconductor Nanoparticles
Authors: Kumar Jatish , Thomas K. George , Liz‐Marzan Luis M.
Published: November 2016

Review: 157 refs.
ChemInform Abstract: Beyond Fischer and Schrock Carbenes: Non‐Heteroatom‐Stabilized Group 6 Metal Carbene Complexes — A General Overview
Authors: Santamaria Javier , Aguilar Enrique
Published: November 2016

Review: [of the usefulness of these organometallic reagents in organic synthesis; 82 refs.
ChemInform Abstract: Opportunities of Immobilized Homogeneous Metathesis Complexes as Prominent Heterogeneous Catalysts
Authors: Dewaele Annelies , Verpoort Francis , Sels Bert
Published: November 2016

Review: [122 refs.
ChemInform Abstract: Diels—Alder Approaches for the Synthesis of Bridged Bicyclic Systems: Synthetic Applications of (7‐Hetero)norbornadienes
Authors: Moreno‐Clavijo Elena , Carmona Ana T. , Robina Inmaculada , Moreno‐Vargas Antonio J.
Published: November 2016

Review: approaches used in the last ten years for the synthesis of (7‐hetero)norbornadenes and their synthetic applications
ChemInform Abstract: Singlet Oxygen as a Reagent in Organic Synthesis
Authors: Griesbeck Axel G. , Sillner Sarah , Kleczka Margarethe
Published: November 2016

Review: [134 refs.
ChemInform Abstract: Synthesis of Spiro‐fused Heterocyclic Scaffolds Through Multicomponent Reactions Involving Isatin
Authors: Ziarani Ghodsi Mohammadi , Moradi Razieh , Lashgari Negar
Published: November 2016

Review: data from 2012 to 2015; 207 refs.
ChemInform Abstract: Reaching the South: Metal‐Catalyzed Transformation of the Aromatic para‐Position
Authors: Dey Aniruddha , Maity Soham , Maiti Debabrata
Published: November 2016

Review: [55 refs.
ChemInform Abstract: Endothioxopeptides: A Conformational Overview
Authors: De Zotti Marta , Peggion Cristina , Biondi Barbara , Crisma Marco , Formaggio Fernando , Toniolo Claudio
Published: November 2016

Review: 142 refs.
ChemInform Abstract: Targeted Covalent Inhibitors for Drug Design
Authors: Baillie Thomas A.
Published: November 2016

Review: 122 refs.
ChemInform Abstract: Graphene‐Based Metal‐Free Catalysts for Catalytic Reactions in the Liquid Phase
Authors: Tang Pei , Hu Gang , Li Mengzhu , Ma Ding
Published: November 2016

Review: 95 refs.
ChemInform Abstract: Nanoporous Conducting Polymer‐Based Coatings in Microextraction Techniques for Environmental and Biomedical Applications
Authors: Szultka‐Mlynska Malgorzata , Olszowy Pawel , Buszewski Boguslaw
Published: November 2016

Review: 77 refs.
ChemInform Abstract: Cooperative Catalysis of Combined Systems of Transition‐Metal Complexes with Lewis Acids: Theoretical Understanding
Authors: Guan Wei , Zeng Guixiang , Kameo Hajime , Nakao Yoshiaki , Sakaki Shigeyoshi
Published: November 2016

Review: [58 refs.
A new outsourcing conditional proxy re‐encryption suitable for mobile cloud environment
Authors: Son Junggab , Kim Donghyun , Bhuiyan Md Zakirul Alam , Hussain Rasheed , Oh Heekuck
Published: November 2016

The mobile cloud is a highly heterogenous and constantly evolving network of numerous portable devices utilizing the powerful back‐end cloud infrastructure to overcome their severe deficiency in computing resource and offer various services such as data sharing. Inherently, in mobile cloud, the risk of user privacy invasion by the cloud operator is high. The conditional proxy re‐encryption (CPRE) is a useful concept for secure group data sharing via cloud while preserving the privacy of the shared data from any unintended third parties including the cloud operator. Unfortunately, the state‐of‐art CPRE is not particularly designed for mobile cloud environment and therefore imposes heavy burdens to the weak mobile cloud clients. This paper introduces a new CPRE scheme, namely the CPRE for mobile cloud, which utilizes the back‐end cloud to the extreme extent so that the overhead of terminals is drastically reduced. Specifically, our scheme outsources a significant amount of computation overhead caused by the following functions at terminals: (a) re‐encryption key generation, (b) condition value change, and (c) decryption, to the cloud. The proposed scheme also allows users to verify the correctness of outsourced computation under refereed delegation of computation model. Our simulation results show CPRE for mobile cloud that outperforms its existing alternatives. Copyright © 2016 John Wiley & Sons, Ltd.
Dopant‐Catalyzed Singlet Exciton Fission
Authors: Snamina Mateusz , Petelenz Piotr
Published: November 2016

In acene‐based molecular crystals, singlet exciton fission occurs through superexchange mediated by two virtual charge‐transfer states. Hence, it is sensitive to their energies, which depend on the local environment. The crucial point is the balance between the charge–quadrupole interactions within the pair of molecules directly involved in the process and those with the surrounding crystal matrix, which are governed by local symmetry and may be influenced by breaking this symmetry. This happens, for example, in the vicinity of a vacancy or an impurity and in the latter case is complemented by polarization energy and potentially by dipolar contributions. Our model calculations indicate that the superexchange coupling is sensitive enough to these factors to enable fission to be catalyzed by judiciously designed dopant molecules. In favorable cases, dipolar dopants are expected to increase the fission rate by an order of magnitude.
Frequency Tuning Range Expansion for the Millimeter‐Wave Band Tunable Filter
Authors: KAWAMURA TAKASHI , OTANI AKIHITO
Published: November 2016

For the realization of the smart community, the Internet of Things (IoT) and sensor technology in the millimeter‐wave band is necessary. The development of these technologies requires accurate spectrum analysis in the frequency domain over 100 GHz. A tunable preselection filter is a key device in building such a spectrum analyzer. In this paper, we propose use of a ridge waveguide to achieve frequency tuning over a wider bandwidth. In addition, we demonstrate an example design and prototype for a filter with a relative bandwidth of 38% (75 GHz to 110 GHz) and 32% (78.1 GHz to 107.5 GHz), respectively.
Pressure Rises Due to Arc Under Insulating Oil in Closed Vessel—Relationship between Bubble Behavior and Pressure Rises
Authors: TADOKORO TOMO , KOTARI MASASHI , OHTAKA TOSHIYA , IWATA MIKIMASA , AMAKAWA TADASHI
Published: November 2016

When a fault arc occurs in oil‐filled electric power equipment such as transformers in transmission and distribution systems, it generates a flammable gas and a dynamic pressure rise that may trigger an explosion. The purpose of this fundamental study is to investigate the effects of the arc under electrical insulation oil on pressure rises in a closed vessel containing air and oil. In particular, this paper is intended to investigate the relationship between the pressure rises and the generated bubble behavior by the arc. The pressure rises in both air and oil are measured under experimental conditions involving an arc current ranging from 2.3 kA to 8.9 kA, an arc duration of 10 ms or 100 ms. Experimental results show that the behavior of a bubble affects the pressure rises in the air and the oil as low‐frequency pressure oscillation comparatively.
A mechanism of self‐organization in a desert with phytogenic mounds
Authors: Quets Jan J. , El‐Bana Magdy I. , Al‐Rowaily Saud L. , Assaeed Abdulaziz M. , Temmerman Stijn , Nijs Ivan
Published: November 2016

Phytogenic mounds or nebkhas are formed by spatially isolated burial‐tolerant plants, which have been trapping windborne sediment within their canopies. They occur in drylands all over the world, and nebkha landscapes are considered intermediate between stable grasslands and unstable deserts with mobile dunes. Depending on the previous state of the landscape, they can thus be viewed both as indicators of desertification and as signs of stabilization. While individual nebkha mounds have been studied extensively, little is known about the organization of nebkha landscapes. In this study, we collected spatiotemporal data of vegetation and topography from four self‐made remotely sensed maps, created over a three‐year period from a study site in central Saudi Arabia dominated by the nebkha‐forming shrub Rhazya stricta Decne. Using logistic regressions and t tests, we found that the nebkha shrubs grow in topographic depressions, while they shrink on topographic highs and in locations with high nebkha densities. We propose that this spatial variation in nebkha growth is driven by water availability, as the few extreme rain events that typically make up the bulk of precipitation in deserts would spatially redistribute to topographic lows, and as nebkha density would positively correlate with competition for water. Our data suggest a novel mechanism of biogeomorphological self‐organization in deserts. The observed nebkha growth in depressions would lead to increased sedimentation on and in between the nebkhas owing to reduced wind speed, which after a time lag might transform depressions into topographic highs on which nebkhas tend to shrink because of water shortage. Shrinking nebkhas, in turn, could provoke soil erosion, on as well as in between the nebkha mounds, which may ultimately transform topographic highs into depressions, thereby closing the cycle of self‐organization.
Temporal patterns in innate immunity parameters in reef‐building corals and linkages with local climatic conditions
Authors: van de Water Jeroen A. J. M. , Lamb Joleah B. , Heron Scott F. , van Oppen Madeleine J. H. , Willis Bette L.
Published: November 2016

Extremes in seasonal environmental conditions can significantly impact the health and physiological functioning of reef corals, underscoring the need for knowledge of seasonally specific baselines from which to monitor and forecast impending stress. Increases above summertime means in seawater temperature, sunlight intensity, turbidity, or sedimentation may reduce coral immunocompetency and increase disease and bleaching susceptibility. We analyzed temporal patterns in innate immunity parameters over nine time points throughout one year to establish baseline levels from which anomalies might be detected for representative species from three major reef‐building coral families (Acroporidae, Faviidae, and Poritidae). Temporal patterns in both phenoloxidase activity and expression of green fluorescent protein‐like proteins varied among the three families, as did overall constitutive levels. For example, Porites cylindrica had 2.8‐fold higher yearly average levels of phenoloxidase activity than Acropora millepora, which had the lowest levels. In contrast, mean fluorescence was lowest in Acropora millepora and highest in Echinopora mammiformis. Relationships between the potential physical drivers (seasonal variation in seawater temperature, rainfall, salinity) and temporal patterns in these parameters also differed among the three species. For example, phenoloxidase activity was positively correlated with seawater temperature in A. millepora, but negatively correlated in both E. mammiformis and P. cylindrica. Distinctions in constitutive levels and temporal patterns in these parameters among species suggest that corals from these three families have evolved different strategies for investing resources into innate immune parameters. Such differences highlight the need for species‐specific baselines and long‐term assessments to accurately predict coral reef trajectories in rapidly changing environments.
Habitat degradation increases functional originality in highly diverse coral reef fish assemblages
Authors: Brandl Simon J. , Emslie Michael J. , Ceccarelli Daniela M. , T. Richards Zoe
Published: November 2016

As anthropogenic and natural disturbances intensify, there is mounting concern about the loss of functionally important or unique species. Functional redundancy, or the presence of several different species occupying similar functional niches, can provide insurance against diversity loss, but evidence for this effect is rare. Likewise, the ways in which functional redundancy patterns respond to disturbances are poorly known, impeding a thorough understanding of community‐level dynamics post disturbance. Here, we use an extensive reduction of hard coral cover following a tropical cyclone to explore the response of a highly diverse reef fish assemblage to habitat degradation. We demonstrate that despite clear trait value‐specific susceptibility of fishes to the disturbance, five of six functional indices (including functional richness and evenness) showed no relationship with habitat degradation. In contrast, functional originality, which quantifies the average functional uniqueness of species within an assemblage, increased post disturbance, exhibiting a negative, albeit weak, relationship with decreasing coral cover. The increase in functional originality is simultaneously driven by the loss of functionally similar species in susceptible groups (predominantly small planktivorous and omnivorous species that associate with live coral habitat) and the addition of functionally unique species in groups that benefit from the disturbance (large, non‐territorial species feeding on algal turfs, detritus, and invertebrates). Our findings suggest that coral reefs with high coral cover can foster fish assemblages with low functional originality (i.e., high functional redundancy), therefore preventing detectible changes in some of the most commonly applied functional indices post disturbance. However, we caution that the limited resolution of trait‐based approaches may mask the loss of functionally unique species and that, with an increase in functional originality, post disturbance assemblages may be less suited to adequately maintain certain ecosystem functions in the face of future disturbances. Thus, there is an urgent need for further exploration of the dynamics between disturbances, functional redundancy, and ecosystem functioning.
Drought resistance across California ecosystems: evaluating changes in carbon dynamics using satellite imagery
Authors: Malone Sparkle L. , Tulbure Mirela G. , Pérez‐Luque Antonio J. , Assal Timothy J. , Bremer Leah L. , Drucker Debora P. , Hillis Vicken , Varela Sara , Goulden Michael L.
Published: November 2016

Drought is a global issue that is exacerbated by climate change and increasing anthropogenic water demands. The recent occurrence of drought in California provides an important opportunity to examine drought response across ecosystem classes (forests, shrublands, grasslands, and wetlands), which is essential to understand how climate influences ecosystem structure and function. We quantified ecosystem resistance to drought by comparing changes in satellite‐derived estimates of water‐use efficiency (WUE = net primary productivity [NPP]/evapotranspiration [ET]) under normal (i.e., baseline) and drought conditions (ΔWUE = WUE2014 − baseline WUE). With this method, areas with increasing WUE under drought conditions are considered more resilient than systems with declining WUE. Baseline WUE varied across California (0.08 to 3.85 g C/mm H2O) and WUE generally increased under severe drought conditions in 2014. Strong correlations between ΔWUE, precipitation, and leaf area index (LAI) indicate that ecosystems with a lower average LAI (i.e., grasslands) also had greater C‐uptake rates when water was limiting and higher rates of carbon‐uptake efficiency (CUE = NPP/LAI) under drought conditions. We also found that systems with a baseline WUE ≤ 0.4 exhibited a decline in WUE under drought conditions, suggesting that a baseline WUE ≤ 0.4 might be indicative of low drought resistance. Drought severity, precipitation, and WUE were identified as important drivers of shifts in ecosystem classes over the study period. These findings have important implications for understanding climate change effects on primary productivity and C sequestration across ecosystems and how this may influence ecosystem resistance in the future.
Synthesis and Photophysical Properties of Triazolyl IrIII Nucleosides
Authors: Passays Johan , Rubay Christophe , Marcélis Lionel , Elias Benjamin
Published: November 2016

DNA‐based nanomaterials are the subject of numerous researches. A series of modified nucleobases were synthesized either to construct a double helix where the natural H‐bonded bases are replaced by metal‐coordinated liganosides or to introduce a punctual modification inside a natural DNA structure. Thanks to their photophysical and photochemical properties, iridium(III) complexes are of increasing interest in the development of sensors and photoreactants for biochemical applications. In this view, we previously demonstrated that some IrIII complexes are able to photoreact with DNA through photoinduced electron transfer. In this study, we report the synthesis and characterization of nucleosides bearing iridium complexes with unaltered properties compared to their parent complexes.
Synthesis of Covalently Linked Oligo(phenyleneethynylene) Wires Incorporating Dithiafulvene Units: Redox‐Active “H‐Cruciforms”
Authors: Jørgensen Frederik Præstholm , Petersen Johannes F. , Andersen Cecilie Lindholm , Skov Anders B. , Jevric Martyn , Hammerich Ole , Nielsen Mogens Brøndsted
Published: November 2016

Controlled alignment and self‐assembly of molecular wires is one of the challenges in the field of molecular electronics. Here, we take an approach by which two oligo(phenyleneethynylene)s (OPEs) are linked together through one vinylogous linker. These molecules thus incorporate a central stilbene part from which the two OPE wires propagate in a so‐called “H‐cruciform”‐like motif. Each ring of the central stilbene unit also contains a redox‐active dithiafulvene (DTF) unit and this part of the molecule can thus be considered as an extended tetrathiafulvalene (TTF). Here, we present how such H‐cruciforms based on OPE3 and OPE5 molecular wires are prepared by Sonogashira coupling reactions and how the OPEs are functionalized with thioester end‐caps as potential electrode anchoring groups. The optical and redox properties of these molecules are also presented. Unsymmetrical systems are achieved by subjecting a differentially protected diethynyl‐substituted derivative of terephthalaldehyde to a phosphite‐mediated coupling reaction in the presence of a 1,3‐dithiol‐2‐thione. This reaction forms the central stilbene‐extended TTF with alkyne substituents and relies on an “umpolung” of the para substituents from electron‐withdrawing CHO groups to electron‐donating DTF groups in a conversion also promoted by the phosphite.
Nucleophilic 18F‐Labeling of Spirocyclic Iodonium Ylide or Boronic Pinacol Ester Precursors: Advantages and Disadvantages
Authors: Petersen Ida Nymann , Kristensen Jesper Langgaard , Herth Matthias Manfred
Published: November 2016

The field of labeling electron‐rich aryl compounds with nucleophilic [18F]fluoride has recently expanded with radiofluorination strategies that apply boronic esters or spirocyclic iodonium ylides as precursors. Herein, we present a direct comparison of these strategies by using nine chemically diverse model compounds. In general, spirocyclic iodonium ylides outperform the boronic esters.
Electrochemical Characterization of the Microfabricated Electrochemical Sensor‐Array System
Authors: Pitman Kätlin , Raud Merlin , Scotti Gianmario , Jokinen Ville P. , Franssila Sami , Nerut Jaak , Lust Enn , Kikas Timo
Published: November 2016

Microfabrication technology has been used to prepare a microchip sensor‐array with six sets of platinum electrodes. Chromium/platinum (10 nm/100 nm thick) were sputtered on a borosilicate wafer and patterned by wet etching method. The electrodes were designed with working electrode area of 700×400 μm in the middle and a 200 μm wide and 2600 μm long counter electrode surrounding it from three sides in a U‐shape. The connection pads (1000×1500 μm) were located at the edge of a sensor‐array chip. Silicon wafer was etched through to form holes with slanting side walls for immobilization cavities. The silicon and the borosilicate wafers were adhesion bonded with SU‐8 epoxy resin. The cyclic voltammetry and electrochemical impedance experiments were carried out in a three‐electrode electrochemical system to characterize the fabricated sensor‐array chip. The results show that the current density depends on the electrode potential sweep rate ν. Also, current density depends on the concentration of potassium hexacyanoferrate(III). At slow potential sweep rates (ν≤0.01 V s−1) the steady‐state signal is achieved and the electrodes behave as micro‐electrodes. Such an array is a promising candidate for fast and simple biochemical oxygen demand (BOD) measurements.
A moving particle semi‐implicit method for free surface flow: Improvement in inter‐particle force stabilization and consistency restoring
Authors: Xiang Hao , Chen Bin
Published: November 2016

The moving particle semi‐implicit (MPS) method has been widely applied in free surface flows. However, the implementation of MPS remains limited because of compressive instability occurred when the particles are under compressive stress states. This study proposed an inter‐particle force stabilization and consistency restoring MPS (IFS‐CR‐MPS) method to overcome this numerical instability. For inter‐particle force stabilization, a hyperbolic‐shaped quintic kernel function is developed with a non‐negative and smooth second order derivative to satisfy the stability criterion under compressive stress state. Then, a contrastive study is conducted on the contradiction between the common understanding of the conventional MPS hyperbolic‐shaped kernel function and its performance. The result shows that the conventional MPS hyperbolic‐shaped kernel function can easily cause violent repulsive inter‐particle force and then lead to the compressive instability. Therefore, the first order derivative of the modified hyperbolic‐shaped quintic kernel function is recommended as the form of the contribution of the neighbor particles to achieve a more stable inter‐particle repulsive force. For consistency restoring, the Taylor series expansion and the hyperbolic‐shaped quintic kernel are combined to improve the accuracy of the viscosity and pressure calculation. The IFS‐CR‐MPS algorithm is subsequently verified by the inviscid hydrostatic pressure, jet impacting, and viscous droplet impacting problems. These results can be used for choosing kernel function and the contribution of neighbor particles in particle methods. Copyright © 2016 John Wiley & Sons, Ltd.
Competitive Markets and Clean Energy Goals—Theory vs. Practice
Authors: DeCotis Paul A.
Published: November 2016

Very simply speaking, competitive markets are characterized by having many market participants buying and selling a particular product or service, with no one participant advantaged over another except through innovation or time to market.
Neural signatures of trust in reciprocity: A coordinate‐based meta‐analysis
Authors: Bellucci Gabriele , Chernyak Sergey V. , Goodyear Kimberly , Eickhoff Simon B. , Krueger Frank
Published: November 2016

Trust in reciprocity (TR) is defined as the risky decision to invest valued resources in another party with the hope of mutual benefit. Several fMRI studies have investigated the neural correlates of TR in one‐shot and multiround versions of the investment game (IG). However, an overall characterization of the underlying neural networks remains elusive. Here, a coordinate‐based meta‐analysis was employed (activation likelihood estimation method, 30 articles) to investigate consistent brain activations in each of the IG stages (i.e., the trust, reciprocity and feedback stage). Results showed consistent activations in the anterior insula (AI) during trust decisions in the one‐shot IG and decisions to reciprocate in the multiround IG, likely related to representations of aversive feelings. Moreover, decisions to reciprocate also consistently engaged the intraparietal sulcus, probably involved in evaluations of the reciprocity options. On the contrary, trust decisions in the multiround IG consistently activated the ventral striatum, likely associated with reward prediction error signals. Finally, the dorsal striatum was found consistently recruited during the feedback stage of the multiround IG, likely related to reinforcement learning. In conclusion, our results indicate different neural networks underlying trust, reciprocity, and feedback learning. These findings suggest that although decisions to trust and reciprocate may elicit aversive feelings likely evoked by the uncertainty about the decision outcomes and the pressing requirements of social standards, multiple interactions allow people to build interpersonal trust for cooperation via a learning mechanism by which they arguably learn to distinguish trustworthy from untrustworthy partners. Hum Brain Mapp 38:1233–1248, 2017. © 2016 Wiley Periodicals, Inc.
Cognitive phenotypes in parkinson's disease differ in terms of brain‐network organization and connectivity
Authors: Lopes Renaud , Delmaire Christine , Defebvre Luc , Moonen Anja J. , Duits Annelien A. , Hofman Paul , Leentjens Albert F.G. , Dujardin Kathy
Published: November 2016

Cognitive deficits are common in Parkinson's disease and we suspect that dysfunctions of connected brain regions can be the source of these deficits. The aim of the present study was to investigate changes in whole‐brain intrinsic functional connectivity according to differences in cognitive profiles in Parkinson's disease. 119 participants were enrolled and divided into four groups according to their cognitive phenotypes (determined by a cluster analysis): (i) 31 cognitively intact patients (G1), (ii) 31 patients with only slight mental slowing (G2), (iii) 43 patients with mild to moderate deficits mainly in executive functions (G3), (iv) 14 patients with severe deficits in all cognitive domains (G4–5). Rs‐fMRI whole‐brain connectivity was examined by two complementary approaches: graph theory for studying network functional organization and network‐based statistics (NBS) for exploring functional connectivity amongst brain regions. After adjustment for age, duration of formal education and center of acquisition, there were significant group differences for all functional organization indexes: functional organization decreased (G1 > G2 > G3 > G4‐5) as cognitive impairment worsened. Between‐group differences in functional connectivity (NBS corrected, P < 0.01) mainly concerned the ventral prefrontal, parietal, temporal and occipital cortices as well as the basal ganglia. In Parkinson's disease, brain network organization is progressively disrupted as cognitive impairment worsens, with an increasing number of altered connections between brain regions. We observed reduced connectivity in highly associative areas, even in patients with only slight mental slowing. The association of slowed mental processing with loss of connectivity between highly associative areas could be an early marker of cognitive impairment in Parkinson's disease and may contribute to the detection of prodromal forms of Parkinson's disease dementia. Hum Brain Mapp 38:1604–1621, 2017. © 2016 Wiley Periodicals, Inc.
Acute systemic MK‐801 induced functional uncoupling between hippocampal areas CA3 and CA1 with distant effect in the retrosplenial cortex
Authors: Buchtová Helena , Fajnerová Iveta , Stuchlík Aleš , Kubík Štěpán
Published: November 2016

The hippocampus and retrosplenial cortex are integrated within a higher‐order cognitive circuit supporting relational (spatial, contextual, episodic) forms of learning and memory. Hippocampal place cells can coordinate multiple parallel representations in the same physical environment. Novel environment exploration triggers expression of immediate‐early genes (IEGs) Arc and Homer1a in spatial context‐specific ensembles of CA1 and CA3 neurons. Less is know about ensemble coding in the retrosplenial cortex (RSC), a region directly connected and functionally coupled to CA1. Hippocampal and retrosplenial damage is found in patients with schizophrenia alongside cognitive deficits affecting relational memory. Systemic administration of non‐competitive NMDAR antagonists such as MK‐801 is used to model psychosis in animals and humans. Acute systemic MK‐801 (0.15 mg/kg) impaired cognitive control in rats and ensemble code for spatial context in CA1. Here, we use expression of immediate‐early genes Arc and Homer 1a to examine ensemble coding in rat CA3 and RSC to test if the effect of MK‐801 extends upstream and downstream of CA1, respectively. Different rats explored the same context twice (A/A), explored two distinct contexts (A/B) or remained in their home cage (CC). In contrast to CA1, MK‐801 did not affect ensemble coding in CA3. Unlike CA3 and CA1, similarity of RSC ensembles active during exploration did not reflect change in spatial context, but MK‐801 (0.15 mg/kg) increased similarity in RSC ensembles active during spontaneous behavior in the home cage. The data provide support for MK‐801‐induced functional uncoupling between CA3 and CA1 and suggest that ensemble coding deficit may extend downstream of CA1. This deficit may reflect hyperassociative state in the cognitive circuit underlying cognitive disorganization in psychosis. © 2016 Wiley Periodicals, Inc.
Repetition reveals ups and downs of hippocampal, thalamic, and neocortical engagement during mnemonic decisions
Authors: Reagh Zachariah M. , Murray Elizabeth A. , Yassa Michael A.
Published: November 2016

The extent to which current information is consistent with past experiences and our capacity to recognize or discriminate accordingly are key factors in flexible memory‐guided behavior. Despite a wealth of evidence linking hippocampal and neocortical computations to these phenomena, many important factors remain poorly understood. One such factor is repeated encoding of learned information. In this experiment, participants completed a task in which study stimuli were incidentally encoded either once or three separate times during high‐resolution fMRI scanning. We asked how repetition influenced recognition and discrimination memory judgments, and how this affects engagement of hippocampal and neocortical regions. Repetition revealed shifts in engagement in an anterior (ventral) CA1‐thalamic‐medial prefrontal network related to true and false recognition. Conversely, repetition revealed shifts in a posterior (dorsal) dentate/CA3‐parahippocampal‐restrosplenial network related to accurate discrimination. These differences in engagement were accompanied by task‐related correlations in respective anterior and posterior networks. In particular, the anterior thalamic region observed during recognition judgments is functionally and anatomically consistent with nucleus reuniens in humans, and was found to mediate correlations between the anterior CA1 and medial prefrontal cortex. These findings offer new insights into how repeated experience affects memory and its neural substrates in hippocampal‐neocortical networks. © 2016 Wiley Periodicals, Inc.
Visual short‐term memory for high resolution associations is impaired in patients with medial temporal lobe damage
Authors: Koen Joshua D. , Borders Alyssa A. , Petzold Michael T. , Yonelinas Andrew P.
Published: November 2016

The medial temporal lobe (MTL) plays a critical role in episodic long‐term memory, but whether the MTL is necessary for visual short‐term memory is controversial. Some studies have indicated that MTL damage disrupts visual short‐term memory performance whereas other studies have failed to find such evidence. To account for these mixed results, it has been proposed that the hippocampus is critical in supporting short‐term memory for high resolution complex bindings, while the cortex is sufficient to support simple, low resolution bindings. This hypothesis was tested in the current study by assessing visual short‐term memory in patients with damage to the MTL and controls for high resolution and low resolution object‐location and object‐color associations. In the location tests, participants encoded sets of two or four objects in different locations on the screen. After each set, participants performed a two‐alternative forced‐choice task in which they were required to discriminate the object in the target location from the object in a high or low resolution lure location (i.e., the object locations were very close or far away from the target location, respectively). Similarly, in the color tests, participants were presented with sets of two or four objects in a different color and, after each set, were required to discriminate the object in the target color from the object in a high or low resolution lure color (i.e., the lure color was very similar or very different, respectively, to the studied color). The patients were significantly impaired in visual short‐term memory, but importantly, they were more impaired for high resolution object‐location and object‐color bindings. The results are consistent with the proposal that the hippocampus plays a critical role in forming and maintaining complex, high resolution bindings. © 2016 Wiley Periodicals, Inc.
Material Specificity Drives Medial Temporal Lobe Familiarity But Not Hippocampal Recollection
Authors: Kafkas Alex , Migo Ellen M. , Morris Robin G. , Kopelman Michael D. , Montaldi Daniela , Mayes Andrew R.
Published: November 2016

The specific role of the perirhinal (PRC), entorhinal (ERC) and parahippocampal cortices (PHC) in supporting familiarity‐based recognition remains unknown. An fMRI study explored whether these medial temporal lobe (MTL) structures responded in the same way or differentially to familiarity as a function of stimulus type at recognition. A secondary aim was to explore whether the hippocampus responds in the same way to equally strong familiarity and recollection and whether this is influenced by the kind of stimulus involved. Univariate and multivariate analyses revealed that familiarity responses in the PRC, ERC, PHC and the amygdala are material‐specific. Specifically, the PRC and ERC selectively responded to object familiarity, while the PHC responded to both object and scene familiarity. The amygdala only responded to familiarity memory for faces. The hippocampus did not respond to stimulus familiarity for any of the three types of stimuli, but it did respond to recollection for all three types of stimuli. This was true even when recollection was contrasted to equally accurate familiarity. Overall, the findings suggest that the role of the MTL neocortices and the amygdala in familiarity‐based recognition depends on the kind of stimulus in memory, whereas the role of the hippocampus in recollection is independent of the type of cuing stimulus. © 2016 The Authors Hippocampus Published by Wiley Periodicals, Inc.
Spectral diffuse reflectance and autofluorescence imaging can perform early prediction of blood vessel occlusion in skin flaps
Authors: Chen Shuo , Zhu Caigang , Hoe‐Kong Chui Christopher , Sheoran Gyanendra , Tan Bien‐Keem , Liu Quan
Published: November 2016

Flap transfer has become a common technique in reconstructive surgery. However, a significant number of compromised skin flaps are not successfully salvaged because the current clinical method for flap assessment relies heavily on the clinician's experience. Vascular occlusion is the major reason for flap failure, thus the accurate and objective early prediction of blood vessel occlusion is vitally important. Our parallel point measurement study has demonstrated the great potential of joint diffuse reflectance and autofluorescence spectroscopy in the early detection and differentiation of venous and arterial occlusion in skin flaps. Unfortunately, the technique of point measurements is not suitable to examine a large skin flap when a high spatial resolution is required. In this study, we attempted to overcome this problem by performing spectral diffuse reflectance and autofluorescence imaging on a rat skin flap model. Both imaging data and reconstructed spectra were used to statistically differentiate control flaps, arterially occluded flaps and venously occluded flaps. Our preliminary results suggest that the technique of joint diffuse reflectance and autofluorescence spectroscopic imaging can achieve high classification accuracy thus could be used to detect and differentiate flaps with venous and arterial occlusion accurately at an early time point in a large skin flap.

Typical reconstructed spectra of (a) diffuse reflectance and (b) autofluorescence after normalization.

magnified image

Typical reconstructed spectra of (a) diffuse reflectance and (b) autofluorescence after normalization.
Prevalence and incidence of sarcopenia in the very old: findings from the Newcastle 85+ Study
Authors: Dodds Richard Matthew , Granic Antoneta , Davies Karen , Kirkwood Thomas B. L. , Jagger Carol , Sayer Avan Aihie
Published: November 2016

Introduction

Recognition that an older person has sarcopenia is important because this condition is linked to a range of adverse outcomes. Sarcopenia becomes increasingly common with age, and yet there are few data concerning its descriptive epidemiology in the very old (aged 85 years and above). Our aims were to describe risk factors for sarcopenia and estimate its prevalence and incidence in a British sample of the very old.

Methods

We used data from two waves (2006/07 and 2009/10) of the Newcastle 85+ Study, a cohort born in 1921 and registered with a Newcastle/North Tyneside general practice. We assessed sarcopenia status using the European Working Group on Sarcopenia in Older People (EWGSOP) definition. Grip strength was measured using a Takei digital dynamometer (Takei Scientific Instruments Ltd., Niigata, Japan), gait speed was calculated from the Timed Up and Go test, and lean mass was estimated using a Tanita‐305 body fat analyzer. We used logistic regression to examine associations between risk factors for prevalent sarcopenia at baseline and incident sarcopenia at follow‐up.

Results

European Working Group on Sarcopenia in Older People sarcopenia was present in 21% of participants at baseline [149/719 participants, mean age 85.5 (0.4) years]. Many participants had either slow gait speed or weak grip strength (74.3%), and hence measurement of muscle mass was frequently indicated by the EWGSOP definition. Incidence data were available for 302 participants, and the incident rate was 3.7 cases per 100 person years at risk. Low Standardized Mini‐Mental State Examination, lower occupational social class, and shorter duration of education were associated with sarcopenia at baseline, while low muscle mass was associated with incident sarcopenia. Low body mass index (BMI) was a risk factor for both in a graded fashion, with each unit decrease associated with increased odds of prevalent [odds ratio (OR) 1.29, 95% confidence interval (CI): 1.21, 1.37] and incident (OR 1.20, 95% CI: 1.08, 1.33) sarcopenia.

Conclusions

To our knowledge, this is the first study to describe prevalence and incidence of EWGSOP sarcopenia in the very old. Low BMI was a risk factor for both current and future sarcopenia; indeed, there was some evidence that low BMI may be a reasonable proxy for low lean mass. Overall, the high prevalence of sarcopenia among the very old suggests that this group should be a focus for future research.
Towards understanding the distribution and tumor targeting of sericin regulated spherical calcium phosphate nanoparticles
Authors: Zhao Ruibo , Ren Xiaoyuan , Xie Chungang , Kong Xiangdong
Published: November 2016

The study of calcium phosphate (CaP) nanoparticles in vivo is still incomplete, which has limited their applications for biomedical delivery. Herein, we synthesized amorphous spherical calcium phosphate (S‐CaP) nanoparticles with an average size of 80 nm via a co‐precipitation method in the presence of silk sericin as the regulation template. S‐CaP was labeled by the near‐infrared dye reagent DiR, and then, the labeled nanoparticles (S‐CaP@DiR) were used to investigate the distribution and degradation in healthy mice by IVIS and TEM. The results showed that the S‐CaP nanoparticles were mainly distributed in the liver, and ∼90% of them (500 μg) could be degraded by the liver within 2 weeks. Tumor‐bearing mice were then prepared, and the S‐CaP was injected intravenously. Strikingly, the nanoparticles can effectively target solid tumors in cancer cell‐bearing mice, indicating that the solid tumor was a foundation for the enrichment of the nanoparticles by the EPR effect, which showed the important potential of biodegradable inorganic nanoparticles in clinical drugs for tumor therapy.
Atomic force microscopy and lamins: A review study towards future, combined investigations
Authors: Pecorari Ilaria , Puzzi Luca , Sbaizero Orfeo
Published: November 2016

In the last decades, atomic force microscopy (AFM) underwent a rapid and stunning development, especially for studying mechanical properties of biological samples. The numerous discoveries relying to this approach, have increased the credit of AFM as a versatile tool, and potentially eligible as a diagnostic equipment. Meanwhile, it has become strikingly evident that lamins are involved on the onset and development of certain diseases, including cancer, Hutchinson‐Gilford progeria syndrome, cardiovascular pathologies, and muscular dystrophy. A new category of pathologies has been defined, the laminopathies, which are caused by mutations in the gene encoding for A‐type lamins. As the majority of medical issues, lamins, and all their related aspects can be considered as a quite complex problem. Indeed, there are many facets to explore, and this definitely requires a multidisciplinary approach. One of the most intriguing aspects concerning lamins is their remarkable contribute to cells mechanics. Over the years, this has led to the speculation of the so‐called “structural hypothesis”, which attempts to elucidate the etiology and some features of the laminopathies. Among the various techniques tried to figure out the role of lamins in the cells mechanics, the AFM has been already successfully applied, proving its versatility. Therefore, the present work aims both to highlight the qualities of AFM and to review the most relevant knowledge about lamins, in order to promote the study of the latter, taking advantage from the former. Microsc. Res. Tech. 80:97–108, 2017. © 2016 Wiley Periodicals, Inc.
Influence of acceleration setting reaction by halogen light‐curing on GIC–dentin interface: Qualitative analysis by SEM
Authors: Yoshioka Laysa , Tedesco Tamara Kerber , Calvo Ana Flávia Bissoto , Kim Sabrina Sun Ha , Malagrana Anna Paula Vieira Ferreira Prado , Raggio Daniela Prócida
Published: November 2016

The aim of this study was to evaluate by scanning electron microscope (SEM) photomicrographs the influence of application of halogen light‐curing for fastening the set reaction of high‐viscosity glass ionomer cements (GIC) by assessing the material/dentin interface. Twelve human primary canines were assigned in four groups (n = 3) according to the GIC (Fuji IX, GC or Maxxion R, FGM) and application of halogen light‐curing (60 sec or control—no external energy). Blocks with approximately 6 mm of height were buildup on previously pre‐treated dentin surface in according to the experimental group. After storage at 37 °C, 100% humidity for 48 h, the specimens were then sectioned in slices with 1‐mm thick. The slices were qualitative analyzed using SEM to evaluate possible structural changes. Two examiners independently evaluated the images in order to observe the spherical hollow spaces of each tooth. The photomicrographs revealed the presence of spherical hollow spaces in all experimental groups. However, in both groups that received halogen light‐curing application, it was possible to observe that the presence of these hollow spaces decreased in size and quantity. It can be concluded that the halogen light‐curing application positively decreases in size and quantity in the presence of spherical hollow spaces in GIC.
Coastal upwelling trends under future warming scenarios from the CORDEX project along the Galician coast (NW Iberian Peninsula)
Authors: Alvarez I. , Lorenzo M. N. , deCastro M. , Gomez‐Gesteira M.
Published: November 2016

Upwelling Index trends derived from wind speed were analysed along the Galician coast using simulations from EURO‐CORDEX project (12.5 km). Data from this project were compared to ENSEMBLES and Cross‐Calibrated Multi‐Platform (CCMP) (25 km) data to investigate the performance of these high spatial resolution data in the ability to represent the evolution of Upwelling Index. Results suggest that differences between Upwelling Index derived from CCMP and modelled data exist all along the coast over the last decades. Both EURO‐CORDEX and ENSEMBLES data tend to overestimate Upwelling Index intensity (in absolute terms) regarding CCMP data. Future climate projections from EURO‐CORDEX show a significant strengthening trend in Upwelling Index intensity derived from wind data and in the frequency of strong upwelling events during the upwelling season (April–September).