bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced snow cover alters root‐microbe interactions and decreases nitrification rates in a northern hardwood forest
Authors: Sorensen Patrick O. , Templer Pamela H. , Christenson Lynn , Duran Jorge , Fahey Timothy , Fisk Melany C. , Groffman Peter M. , Morse Jennifer L. , Finzi Adrien C.
Published: September 2016

Snow cover is projected to decline during the next century in many ecosystems that currently experience a seasonal snowpack. Because snow insulates soils from frigid winter air temperatures, soils are expected to become colder and experience more winter soil freeze‐thaw cycles as snow cover continues to decline. Tree roots are adversely affected by snowpack reduction, but whether loss of snow will affect root‐microbe interactions remains largely unknown. The objective of this study was to distinguish and attribute direct (e.g., winter snow‐ and/or soil frost‐mediated) vs. indirect (e.g., root‐mediated) effects of winter climate change on microbial biomass, the potential activity of microbial exoenzymes, and net N mineralization and nitrification rates. Soil cores were incubatedin situin nylon mesh that either allowed roots to grow into the soil core (2 mm pore size) or excluded root ingrowth (50 μm pore size) for up to 29 months along a natural winter climate gradient at Hubbard Brook Experimental Forest,NH(USA). Microbial biomass did not differ among ingrowth or exclusion cores. Across sampling dates, the potential activities of cellobiohydrolase, phenol oxidase, and peroxidase, and net N mineralization rates were more strongly related to soil volumetric water content (P < 0.05;R2 = 0.25–0.46) than to root biomass, snow or soil frost, or winter soil temperature (R2 < 0.10). Root ingrowth was positively related to soil frost (P < 0.01;R2 = 0.28), suggesting that trees compensate for overwinter root mortality caused by soil freezing by re‐allocating resources towards root production. At the sites with the deepest snow cover, root ingrowth reduced nitrification rates by 30% (P < 0.01), showing that tree roots exert significant influence over nitrification, which declines with reduced snow cover. If soil freezing intensifies over time, then greater compensatory root growth may reduce nitrification rates directly via plant‐microbe N competition and indirectly through a negative feedback on soil moisture, resulting in lower N availability to trees in northern hardwood forests.
Coupling behavior of shear deformation and end rotation of elastomeric seismic isolation bearings
Authors: Ishii Ken , Kikuchi Masaru , Nishimura Takuya , Black Cameron J.
Published: September 2016

This paper presents a mechanical model for predicting the behavior of elastomeric seismic isolation bearings subject to combined end rotations and shear deformation. The mechanical model consists of a series of axial springs at the top, mid‐height and bottom of the bearing to vertically reproduce asymmetric bending moment distribution in the bearings. The model can take into account end rotations of the bearing, and the overall rotational stiffness includes the effect of the variation of vertical load on the bearing and the imposed shear deformation. Static bending tests under various combinations of vertical load and shear deformation were performed to identify the mechanical characteristics of bearings. The test results indicate that bearing rotational stiffness increases with increasing vertical load but decreases with increasing shear deformation. Simulation analyses were conducted to validate the new mechanical model. The results of analyses using the new model show very good agreement with experimental observations. A series of seismic response analyses were performed to demonstrate the dynamic behavior of top‐of‐column isolated structures, a configuration where the end rotations of isolation bearings are typically expected to be larger. The results suggest that the end rotations of elastomeric bearings used in practical top‐of‐column isolated structures do not reduce the stability limit of isolation system. Copyright © 2016 John Wiley & Sons, Ltd.
Multilevel compressed block decomposition–based finite‐element domain decomposition method for the fast analysis of finite periodic structures
Authors: Wan Ting , Jiang Zhaoneng
Published: September 2016

An efficient finite‐element domain decomposition method based on the multilevel compressed block decomposition (MLCBD) algorithm is presented. The dual‐primal finite element tearing and interconnecting (FETI‐DP) method is first introduced to generate a nonoverlapping domain decomposition method with good convergence properties. A second‐order transmission condition is adopted to further accelerate the convergence rate of the FETI‐DP. With the MLCBD algorithm, the computational complexity for the direct solution of FETI‐DP subdomain equations can be reduced to be almost logarithmic linear. The accuracy of the MLCBD algorithm is highly adjustable according to practical requirements. Exploiting the repetitiveness of finite periodic structures, the proposed method can significantly reduce the computational costs. Numerical examples demonstrate the effectiveness of the proposed method for the electromagnetic simulation of finite periodic structures.
Screening of lipase inhibitors in Folium Mori with lipase‐linked magnetic microspheres by high‐performance liquid chromatography and evaluation in diabetic mice
Authors: Ma Rui , Weng Hongbo , Liang Jianying
Published: September 2016

A new method for the screening of compounds with hypoglycemic effect from traditional Chinese medicines employing high‐performance liquid chromatography and lipase‐linked magnetic microspheres has been proposed. We hypothesized that the interaction of traditional Chinese medicine extracts with lipase‐linked magnetic microspheres should decrease the concentration of compounds with hypoglycemic effect. Using this approach, the potential lipase inhibitors in Folium Mori extract were investigated. First, lipase was immobilized on magnetic microspheres by a chemical method. Then, by comparing the chromatograms of samples before and after the interaction with lipase‐linked magnetic microspheres, seven compounds of Folium Mori extract were identified. It was found that protocatechuic acid, chlorogenic acid, protocatechualdehyde, rutin, isoquercitrin, astragalin, and dicaffeoylquinic acid B had evident combination with lipase‐linked magnetic microspheres. Their hypoglycemic effects were verified in streptozocin‐induced diabetic mice. In the present study, astragalin was verified to improve the glucose tolerance and lower the level of glucose in streptozocin‐induced diabetic mice, which indicated that astragalin might be a new highly efficient lipase inhibitor. Based on these significant results, this method could be a convenient approach to screen potential lipase inhibitors from traditional Chinese medicines. Meanwhile, it also could be expanded to screen other active compounds in traditional Chinese medicines.
Canthaxanthin: From molecule to function
Authors: Esatbeyoglu Tuba , Rimbach Gerald
Published: September 2016

The aim of this review is to summarize the relevant literature about the use of canthaxanthin in food science and nutrition research. Canthaxanthin is a red‐orange carotenoid that belongs to the xanthophyll group. This naturally occurring pigment is present in bacteria, algae and some fungi. Canthaxanthin is also responsible for the color of flamingo feathers, koi carp skin and crustacean shells. Canthaxanthin is widely used in poultry (broiler, laying hens) as a feed additive. Canthaxanthin can be obtained by total synthesis. The canthaxanthin‐mediated color of foods is an important quality criterion for consumers. Recently, the potential health‐promoting effects of canthaxanthin have been discussed. Canthaxanthin enrichment of LDL has the potential to protect cholesterol from oxidation. In addition to its free radical scavenging and antioxidant properties (e.g., the induction of catalase and superoxide dismutase), canthaxanthin's immunomodulatory activity (e.g., enhancing the proliferation and function of immune competent cells) and its important role in gap junction communication (e.g., induction of the transmembrane protein connexin 43) have been reported. Many studies regarding the potential health benefits of canthaxanthin have been conducted in vitro and should be validated in appropriate in vivo models.
Antimicrobial and Antitumor Screening of Fluorescent 5,7‐Dihydroxy‐4‐Propyl‐2H‐Chromen‐2‐One Derivatives with Docking Studies
Authors: Abd‐El‐Aziz Alaa S. , Alsaggaf Azhaar T , Okasha Rawda M. , Ahmed Hany E. A. , Bissessur Rabin , Abdelghani Amani A. , Afifi Tarek H.
Published: September 2016

A series of novel fluorescent 5,7‐dihydroxy‐4‐propyl‐2H‐chromen‐2‐one derivatives (2a–j) were synthesized and were found to absorb around 322 and 410 nm.All compounds except the nitro‐containing compound exhibited emission wavelengths around 450 nm with good fluorescence quantum yields (ΦF). Their antimicrobial activity was investigated and tested against several human pathogen Gram‐positive, Gram‐negative bacteria and fungi as well as mycobacterium using agar well diffusion method and minimum inhibitory concentrations were reported. All compounds showed significantly potent antimicrobial activities against most bacterial strains compared to reference drugs. Due to their structural similarity to reference drugs clorobiocin and novobiocin, the docking experiments in the ATP binding pocket of DNA gyrase B enzyme revealed that the compounds mostly have the same binding mode as the reference drugs. Moreover, the cytotoxic activity was also evaluated against four different human cell lines and exhibited more potency than the reference drug.
What Bigots Do Say: A Reply to DiFranco
Authors: Caso Ramiro , Lo Guercio Nicolás ,   Philosophy Documentation Center
Published: September 2016

Neutral Counterpart Theories of slurs hold that the truth-conditional contribution of a slur is the same as the truth-conditional contribution of its neutral counterpart. In (2015), DiFranco argues that these theories, even if plausible for single-word slurs like ‘kike’ and ‘nigger’, are not suitable for complex slurs such as ‘slanty-eyed’ and ‘curry muncher’, figurative slurs like ‘Jewish American Princess’, or iconic slurring expressions like ‘ching chong’. In this paper, we argue that these expressions do not amount to genuine counterexamples to neutral counterpart theories of slurs. We provide a positive characterization of DiFranco’s examples that doesn’t deviate from the core of those theories.
Ligand‐dependent ribozymes
Authors: Felletti Michele , Hartig Jörg S.
Published: September 2016

The discovery of catalytic RNA (ribozymes) more than 30 years ago significantly widened the horizon of RNA‐based functions in natural systems. Similarly to the activity of protein enzymes that are often modulated by the presence of an interaction partner, some examples of naturally occurring ribozymes are influenced by ligands that can either act as cofactors or allosteric modulators. Recent discoveries of new and widespread ribozyme motifs in many different genetic contexts point toward the existence of further ligand‐dependent RNA catalysts. In addition to the presence of ligand‐dependent ribozymes in nature, researchers have engineered ligand dependency into natural and artificial ribozymes. Because RNA functions can often be assembled in a truly modular way, many different systems have been obtained utilizing different ligand‐sensing domains and ribozyme activities in diverse applications. We summarize the occurrence of ligand‐dependent ribozymes in nature and the many examples realized by researchers that engineered ligand‐dependent catalytic RNA motifs. We will also highlight methods for obtaining ligand dependency as well as discuss the many interesting applications of ligand‐controlled catalytic RNAs. WIREs RNA 2017, 8:e1395. doi: 10.1002/wrna.1395

This article is categorized under:

RNA-Based Catalysis > RNA–Mediated Cleavage

RNA-Based Catalysis > Miscellaneous RNA–Catalyzed Reactions

Regulatory RNAs/RNAi/Riboswitches > Riboswitches
How to Attain Ultralow Interfacial Tension and Three‐Phase Behavior with a Surfactant Formulation for Enhanced Oil Recovery: a Review—Part 3. Practical Procedures to Optimize the Laboratory Research According to the Current State of the Art in Surfactant Mixing
Authors: Salager Jean‐Louis , Forgiarini Ana M. , Rondón Miguel J.
Published: September 2016

The minimum interfacial tension to be reached in enhanced oil recovery by surfactant flooding implies the attainment of a so‐called optimum formulation. Part 1 of the present review showed that this formulation may be described as a numerical correlation between the involved variables defining the oil, the water, the surfactant and the temperature. Since it is unlikely to find a single surfactant matching the crude/brine/T/P system characteristic of a reservoir, a mixture of at least two surfactant species is always used. The scan technique method to test the mixing requires about ten interfacial tension or phase behavior experiments and results in a single data. Hence, the scan experiments have to be repeated many times to find a minimum tension which is low enough, e.g. 0.001 mN/m, for the given crude oil‐brine system. Part 2 of this review has shown that there are many formulation variables and thus too many possibilities to easily choose experimental conditions. Since there is no simple method to select two or more surfactant species, the choice is made from partial experience or intuition, and sometimes at random. The laboratory time and cost to reach an appropriate optimum formulation is often excessive. Part 3 of this review shows that by cleverly using a three‐surfactant mixture, the experimental work to attain a very low interfacial tension for a given reservoir case can be considerably reduced. It is a matter of using the available information along a proper sequential step by step path toward the optimum.
TGF-beta receptor mediated telomerase inhibition, telomere shortening and breast cancer cell senescence
Authors: Cassar Lucy , Nicholls Craig , Pinto Alex R , Chen Ruping , Wang Lihui , Li He , Liu Jun-Ping
Published: September 2016

Human telomerase reverse transcriptase (hTERT) plays a central role in telomere lengthening for continuous cell proliferation, but it remains unclear how extracellular cues regulate telomerase lengthening of telomeres. Here we report that the cytokine bone morphogenetic protein-7 (BMP7) induces the hTERT gene repression in a BMPRII receptor- and Smad3-dependent manner in human breast cancer cells. Chonic exposure of human breast cancer cells to BMP7 results in short telomeres, cell senescence and apoptosis. Mutation of the BMPRII receptor, but not TGFbRII, ACTRIIA or ACTRIIB receptor, inhibits BMP7-induced repression of the hTERT gene promoter activity, leading to increased telomerase activity, lengthened telomeres and continued cell proliferation. Expression of hTERT prevents BMP7-induced breast cancer cell senescence and apoptosis. Thus, our data suggest that BMP7 induces breast cancer cell aging by a mechanism involving BMPRII receptor- and Smad3-mediated repression of the hTERT gene.
Collision between chemically driven self-propelled drops
Authors: Yabunaka Shunsuke , Yoshinaga Natsuhiko
Published: September 2016

We use analytical and numerical approaches to investigate head-on collisions between two self-propelled drops described as a phase separated binary mixture. Each drop is driven by chemical reactions that isotropically produce or consume the concentration of a third chemical component, which affects the surface tension of the drop. The isotropic distribution of the concentration field is destabilized by motion of the drop, which is created by the Marangoni flow from the concentration-dependent surface tension. This symmetry-breaking self-propulsion is distinct from other self-propulsion mechanisms due to its intrinsic polarity of squirmers and self-phoretic motion; there is a bifurcation point below which the drop is stationary and above which it moves spontaneously. When two drops are moving in the opposite direction along the same axis, their interactions arise from hydrodynamics and concentration overlap. We found that two drops exhibit either an elastic collision or fusion, depending on the distance from their bifurcation point, which may be controlled, for example, by viscosity. An elastic collision occurs when there is a balance between dissipation and the injection of energy by chemical reactions. We derive the reduced equations for the collision between two drops and analyse the contributions from the two interactions. The concentration-mediated interaction is found to dominate the hydrodynamic interaction for a head-on collision.
Developing employee socio-technical flexibility in a multigenerational workforce
Authors: Flinchbaugh Carol , Valenzuela Marcus A. , Li Pingshu
Published: September 2016

This paper identifies how management’s intentional use of participatory management practices can heighten knowledge sharing across a multigenerational workforce through the presence of socio-technical flexibility. In this conceptualization, we identify the value of socio-technical flexibility to effective employee knowledge sharing in three steps. First, we define the prominent characteristics of the current multigenerational workforce. Second, we define the behavioral characteristics of socio-technical flexibility. Third, we describe how an intentional use of salient management practices, including reverse mentoring, flexible work roles, and self-managed teams optimizes multigenerational talents to enhance employee socio-technical flexibility, which in turn, leads to multigenerational knowledge sharing. We believe that by embracing the benefits of multigenerational workforce, management can take intentional steps to create a workplace that optimizes effective knowledge sharing behaviors for improved service through salient participatory management practices.
La Vía Campesina and the UN Committee on World Food Security: Affected publics and institutional dynamics in the nascent transnational public sphere
Authors: Brem-Wilson Josh
Published: September 2016

The emergence of the transnational as a site and object of governance has triggered concern amongst both affected publics subject to these effects, and scholars keen to locate the democratic potentials therein. Increasingly, public sphere theory is being promoted as a lens for interrogating the democratic potential of the transnational. However the project of transposing public sphere theory from its Westphalian origins to the transnational has been frustrated by a lack of empirical examples in which the properties of a transnational public sphere can be easily identified. In this article, examining the encounter between La Vía Campesina and the UN Committee on World Food Security, I argue for the existence of a nascent transnational public sphere in the specific domain of transnational food and agricultural policymaking. The existence of this concrete example, I argue, defends public sphere theory’s transnational turn against either the charge of utopianism, or the need to suspend some of the framework’s core conditions in order to accommodate the ‘actually possible’. It also allows us to advance public sphere theory’s empirical research agenda, and in this article I introduce an analytical framework to take this further.
Mapping Water and Heat Deep Under Long Valley Caldera
Authors: Crane Leah
Published: September 2016

Researchers use electrical resistivity to find the heat source and reservoir feeding Long Valley Caldera's labyrinthine hydrothermal system.
Novel function of FAXDC2 in megakaryopoiesis
Authors: Jin Q , Ren Y , Wang M , Suraneni P K , Li D , Crispino J D , Fan J , Huang Z
Published: September 2016

FAXDC2 (fatty acid hydroxylase domain containing 2) is a member of the fatty acid hydroxylase superfamily. Given the important role of fatty acids in megakaryocytes, we have studied the role of this gene in the development of this lineage. Here we show that the expression of FAXDC2 is constantly elevated during megakaryocyte maturation. In contrast, FAXDC2 is significantly downregulated in acute myeloid leukemia and acute megakaryoblastic leukemia. Moreover, FAXDC2 overexpression promotes the differentiation of megakaryocytic cell lines and primary cells, whereas its knockdown disrupts their maturation. Mechanism study shows that FAXDC2 overexpression enhances extracellular signal-regulated kinase (ERK) signaling and increases RUNX1 (Runt-related transcription factor 1) expression. FAXDC2 also restores megakaryocytic differentiation in cells exposed to an ERK inhibitor or those expressing a dominant negative form of RUNX1. Finally, FAXDC2 overexpression leads to an increase in sphingolipid GM3 synthase, suggesting a potential role of FAXDC2 in lipid metabolism that increases ERK signaling and facilitates megakaryocyte differentiation. Together, these results show that FAXDC2 plays a novel role in development of megakaryocytes and its dysregulation may contribute to abnormal hematopoietic cell development in leukemia.
Phototaxis of synthetic microswimmers in optical landscapes
Authors: Lozano Celia , ten Hagen Borge , Löwen Hartmut , Bechinger Clemens
Published: September 2016

Many microorganisms, with phytoplankton and zooplankton as prominent examples, display phototactic behaviour, that is, the ability to perform directed motion within a light gradient. Here we experimentally demonstrate that sensing of light gradients can also be achieved in a system of synthetic photo-activated microparticles being exposed to an inhomogeneous laser field. We observe a strong orientational response of the particles because of diffusiophoretic torques, which in combination with an intensity-dependent particle motility eventually leads to phototaxis. Since the aligning torques saturate at high gradients, a strongly rectified particle motion is found even in periodic asymmetric intensity landscapes. Our results are in excellent agreement with numerical simulations of a minimal model and should similarly apply to other particle propulsion mechanisms. Because light fields can be easily adjusted in space and time, this also allows to extend our approach to dynamical environments.
Incipient ferroelectricity of water molecules confined to nano-channels of beryl
Authors: Gorshunov B. P. , Torgashev V. I. , Zhukova E. S. , Thomas V. G. , Belyanchikov M. A. , Kadlec C. , Kadlec F. , Savinov M. , Ostapchuk T. , Petzelt J. , Prokleška J. , Tomas P. V. , Pestrjakov E. V. , Fursenko D. A. , Shakurov G. S. , Prokhorov A. S. , Gorelik V. S. , Kadyrov L. S. , Uskov V. V. , Kremer R. K. , Dressel M.
Published: September 2016

Water is characterized by large molecular electric dipole moments and strong interactions between molecules; however, hydrogen bonds screen the dipole–dipole coupling and suppress the ferroelectric order. The situation changes drastically when water is confined: in this case ordering of the molecular dipoles has been predicted, but never unambiguously detected experimentally. In the present study we place separate H2O molecules in the structural channels of a beryl single crystal so that they are located far enough to prevent hydrogen bonding, but close enough to keep the dipole–dipole interaction, resulting in incipient ferroelectricity in the water molecular subsystem. We observe a ferroelectric soft mode that causes Curie–Weiss behaviour of the static permittivity, which saturates below 10 K due to quantum fluctuations. The ferroelectricity of water molecules may play a key role in the functioning of biological systems and find applications in fuel and memory cells, light emitters and other nanoscale electronic devices.
Tuning graphitic oxide for initiator- and metal-free aerobic epoxidation of linear alkenes
Authors: Pattisson Samuel , Nowicka Ewa , Gupta Upendra N. , Shaw Greg , Jenkins Robert L. , Morgan David J. , Knight David W. , Hutchings Graham J.
Published: September 2016

Graphitic oxide has potential as a carbocatalyst for a wide range of reactions. Interest in this material has risen enormously due to it being a precursor to graphene via the chemical oxidation of graphite. Despite some studies suggesting that the chosen method of graphite oxidation can influence the physical properties of the graphitic oxide, the preparation method and extent of oxidation remain unresolved for catalytic applications. Here we show that tuning the graphitic oxide surface can be achieved by varying the amount and type of oxidant. The resulting materials differ in level of oxidation, surface oxygen content and functionality. Most importantly, we show that these graphitic oxide materials are active as unique carbocatalysts for low-temperature aerobic epoxidation of linear alkenes in the absence of initiator or metal. An optimum level of oxidation is necessary and materials produced via conventional permanganate-based methods are far from optimal.
Lateral opening in the intact β-barrel assembly machinery captured by cryo-EM
Authors: Iadanza Matthew G. , Higgins Anna J. , Schiffrin Bob , Calabrese Antonio N. , Brockwell David J. , Ashcroft Alison E. , Radford Sheena E. , Ranson Neil A.
Published: September 2016

The β-barrel assembly machinery (BAM) is a ∼203 kDa complex of five proteins (BamA–E), which is essential for viability in E. coli. BAM promotes the folding and insertion of β-barrel proteins into the outer membrane via a poorly understood mechanism. Several current models suggest that BAM functions through a ‘lateral gating’ motion of the β-barrel of BamA. Here we present a cryo-EM structure of the BamABCDE complex, at 4.9 Å resolution. The structure is in a laterally open conformation showing that gating is independent of BamB binding. We describe conformational changes throughout the complex and interactions between BamA, B, D and E, and the detergent micelle that suggest communication between BAM and the lipid bilayer. Finally, using an enhanced reconstitution protocol and functional assays, we show that for the outer membrane protein OmpT, efficient folding in vitro requires lateral gating in BAM.
Adsorbate-induced lifting of substrate relaxation is a general mechanism governing titania surface chemistry
Authors: Silber David , Kowalski Piotr M. , Traeger Franziska , Buchholz Maria , Bebensee Fabian , Meyer Bernd , Wöll Christof
Published: September 2016

Under ambient conditions, almost all metals are coated by an oxide. These coatings, the result of a chemical reaction, are not passive. Many of them bind, activate and modify adsorbed molecules, processes that are exploited, for example, in heterogeneous catalysis and photochemistry. Here we report an effect of general importance that governs the bonding, structure formation and dissociation of molecules on oxidic substrates. For a specific example, methanol adsorbed on the rutile TiO2(110) single crystal surface, we demonstrate by using a combination of experimental and theoretical techniques that strongly bonding adsorbates can lift surface relaxations beyond their adsorption site, which leads to a significant substrate-mediated interaction between adsorbates. The result is a complex superstructure consisting of pairs of methanol molecules and unoccupied adsorption sites. Infrared spectroscopy reveals that the paired methanol molecules remain intact and do not deprotonate on the defect-free terraces of the rutile TiO2(110) surface.
SCOP/PHLPP1β mediates circadian regulation of long-term recognition memory
Authors: Shimizu Kimiko , Kobayashi Yodai , Nakatsuji Erika , Yamazaki Maya , Shimba Shigeki , Sakimura Kenji , Fukada Yoshitaka
Published: September 2016

Learning and memory depend on the time of day in various organisms, but it is not clear whether and how the circadian clock regulates memory performance. Here we show that consolidation of long-term recognition memory is a circadian-regulated process, which is blunted by disruption of the hippocampal clock. We focused on SCOP, a key molecule regulating hippocampus-dependent long-term memory for objects. The amounts of SCOP and its binding partner K-Ras in the hippocampal membrane rafts exhibit robust circadian changes, and SCOP knockdown in the hippocampal CA1 impairs long-term memory at night. Circadian changes in stimulus-dependent activation of ERK in the hippocampal neurons are dependent on the SCOP levels in the membrane rafts, whileScopknockout abrogates the activation rhythm. We conclude that long-term memory formation is regulated by the circadian clock through SCOP dynamics in the membrane rafts of the hippocampal CA1.
Correction: Corrigendum: Effects of grazing on photosynthetic features and soil respiration of rangelands in the Tianshan Mountains of Northwest China
Authors: Liu Hua , Zang Runguo , Chen Han Y. H.
Published: September 2016

Scientific Reports 6: Article number: 30087; published online: 25 July 2016; updated: 30 September 2016 The original version of this Article contained typographical errors. In the Abstract, “We found that grazing reduced the daily maximum net photosynthetic rate and soil respiration rates by 35% and15%, respectively”.
Impaired ADAMTS9 secretion: A potential mechanism for eye defects in Peters Plus Syndrome
Authors: Dubail Johanne , Vasudevan Deepika , Wang Lauren W. , Earp Sarah E. , Jenkins Michael W. , Haltiwanger Robert S. , Apte Suneel S.
Published: September 2016

Peters Plus syndrome (PPS), a congenital disorder of glycosylation, results from recessive mutations affecting the glucosyltransferase B3GLCT, leading to congenital corneal opacity and diverse extra-ocular manifestations. Together with the fucosyltransferase POFUT2, B3GLCT adds Glucoseβ1-3Fucose disaccharide to a consensus sequence in thrombospondin type 1 repeats (TSRs) of several proteins. Which of these target proteins is functionally compromised in PPS is unknown. We report here that haploinsufficiency of murine Adamts9, encoding a secreted metalloproteinase with 15 TSRs, leads to congenital corneal opacity and Peters anomaly (persistent lens-cornea adhesion), which is a hallmark of PPS. Mass spectrometry of recombinant ADAMTS9 showed that 9 of 12 TSRs with the O-fucosylation consensus sequence carried the Glucoseβ1-3Fucose disaccharide and B3GLCT knockdown reduced ADAMTS9 secretion in HEK293F cells. Together, the genetic and biochemical findings imply a dosage-dependent role for ADAMTS9 in ocular morphogenesis. Reduced secretion of ADAMTS9 in the absence of B3GLCT is proposed as a mechanism of Peters anomaly in PPS. The functional link between ADAMTS9 and B3GLCT established here also provides credence to their recently reported association with age-related macular degeneration.
Social Network Analysis Reveals Potential Fission-Fusion Behavior in a Shark
Authors: Haulsee Danielle E. , Fox Dewayne A. , Breece Matthew W. , Brown Lori M. , Kneebone Jeff , Skomal Gregory B. , Oliver Matthew J.
Published: September 2016

Complex social networks and behaviors are difficult to observe for free-living marine species, especially those that move great distances. Using implanted acoustic transceivers to study the inter- and intraspecific interactions of sand tiger sharks Carcharias taurus, we observed group behavior that has historically been associated with higher order mammals. We found evidence strongly suggestive of fission-fusion behavior, or changes in group size and composition of sand tigers, related to five behavioral modes (summering, south migration, community bottleneck, dispersal, north migration). Our study shows sexually dimorphic behavior during migration, in addition to presenting evidence of a potential solitary phase for these typically gregarious sharks. Sand tigers spent up to 95 consecutive and 335 cumulative hours together, with the strongest relationships occurring between males. Species that exhibit fission-fusion group dynamics pose a particularly challenging issue for conservation and management because changes in group size and composition affect population estimates and amplify anthropogenic impacts.
Accuracy Improvement for Predicting Parkinson’s Disease Progression
Authors: Nilashi Mehrbakhsh , Ibrahim Othman , Ahani Ali
Published: September 2016

Parkinson’s disease (PD) is a member of a larger group of neuromotor diseases marked by the progressive death of dopamineproducing cells in the brain. Providing computational tools for Parkinson disease using a set of data that contains medical information is very desirable for alleviating the symptoms that can help the amount of people who want to discover the risk of disease at an early stage. This paper proposes a new hybrid intelligent system for the prediction of PD progression using noise removal, clustering and prediction methods. Principal Component Analysis (PCA) and Expectation Maximization (EM) are respectively employed to address the multi-collinearity problems in the experimental datasets and clustering the data. We then apply Adaptive Neuro-Fuzzy Inference System (ANFIS) and Support Vector Regression (SVR) for prediction of PD progression. Experimental results on public Parkinson’s datasets show that the proposed method remarkably improves the accuracy of prediction of PD progression. The hybrid intelligent system can assist medical practitioners in the healthcare practice for early detection of Parkinson disease.
Highly Selective Tau-SPECT Imaging Probes for Detection of Neurofibrillary Tangles in Alzheimer’s Disease
Authors: Ono Masahiro , Watanabe Hiroyuki , Kitada Ayane , Matsumura Kenji , Ihara Masafumi , Saji Hideo
Published: September 2016

Neurofibrillary tangles composed of aggregates of hyperphosphorylated tau proteins are one of the neuropathological hallmarks of Alzheimer’s disease (AD) in addition to the deposition of β-amyloid plaques. Since the deposition of tau aggregates is closely associated with the severity of AD, the in vivo detection of tau aggregates may be useful as a biomarker for the diagnosis and progression of AD. In this study, we designed and synthesized a new series of radioiodinated benzoimidazopyridine (BIP) derivatives and evaluated their utility as single photon emission computed tomography (SPECT) imaging agents targeting tau aggregates in AD brains. Five radioiodinated BIP derivatives were successfully prepared in high radiochemical yields and purities. In in vitro autoradiographic studies using postmortem AD brains, all BIP derivatives displayed high accumulation of radioactivity in the brain sections with abundant neurofibrillary tangles, while no marked radioactivity accumulation was observed in the brain sections with only β-amyloid aggregates, indicating that the BIP derivatives exhibited selective binding to tau aggregates. Biodistribution studies in normal mice showed high brain uptake at 2 min postinjection (3.5–4.7% ID/g) and rapid clearance at 60 min postinjection (0.04–0.23% ID/g), which is highly desirable for tau imaging agents. The results of the present study suggest that [123I]BIP derivatives may be useful SPECT agents for the in vivo imaging of tau aggregates in AD.
Identification and impact of discoverers in online social systems
Authors: Medo Matúš , Mariani Manuel S. , Zeng An , Zhang Yi-Cheng
Published: September 2016

Understanding the behavior of users in online systems is of essential importance for sociology, system design, e-commerce, and beyond. Most existing models assume that individuals in diverse systems, ranging from social networks to e-commerce platforms, tend to what is already popular. We propose a statistical time-aware framework to identify the users who differ from the usual behavior by being repeatedly and persistently among the first to collect the items that later become hugely popular. Since these users effectively discover future hits, we refer them as discoverers. We use the proposed framework to demonstrate that discoverers are present in a wide range of real systems. Once identified, discoverers can be used to predict the future success of new items. We finally introduce a simple network model which reproduces the discovery patterns observed in the real data. Our results open the door to quantitative study of detailed temporal patterns in social systems.
Novel proteasome inhibitor ixazomib sensitizes neuroblastoma cells to doxorubicin treatment
Authors: Li Haoyu , Chen Zhenghu , Hu Ting , Wang Long , Yu Yang , Zhao Yanling , Sun Wenijing , Guan Shan , Pang Jonathan C. , Woodfield Sarah E. , Liu Qing , Yang Jianhua
Published: September 2016

Neuroblastoma (NB) is the most common extracranial malignant solid tumor seen in children and continues to lead to the death of many pediatric cancer patients. The poor outcome in high risk NB is largely attributed to the development of chemoresistant tumor cells. Doxorubicin (dox) has been widely employed as a potent anti-cancer agent in chemotherapeutic regimens; however, it also leads to chemoresistance in many cancer types including NB. Thus, developing novel small molecules that can overcome dox-induced chemoresistance is a promising strategy in cancer therapy. Here we show that the second generation proteasome inhibitor ixazomib (MLN9708) not only inhibits NB cell proliferation and induces apoptosis in vitro but also enhances dox-induced cytotoxicity in NB cells. Ixazomib inhibits dox-induced NF-κB activity and sensitizes NB cells to dox-induced apoptosis. More importantly, ixazomib demonstrated potent anti-tumor efficacy in vivo by enhancing dox-induced apoptosis in an orthotopic xenograft NB mouse model. Collectively, our study illustrates the anti-tumor efficacy of ixazomib in NB both alone and in combination with dox, suggesting that combination therapy including ixazomib with traditional therapeutic agents such as dox is a viable strategy that may achieve better outcomes for NB patients.
Spatiotopic updating facilitates perception immediately after saccades
Authors: Fabius Jasper H. , Fracasso Alessio , Van der Stigchel Stefan
Published: September 2016

As the neural representation of visual information is initially coded in retinotopic coordinates, eye movements (saccades) pose a major problem for visual stability. If no visual information were maintained across saccades, retinotopic representations would have to be rebuilt after each saccade. It is currently strongly debated what kind of information (if any at all) is accumulated across saccades and when this information becomes available after a saccade. Here, we use a motion illusion to examine the accumulation of visual information across saccades. In this illusion, an annulus with a random texture slowly rotates and is then replaced with a second texture (motion transient). With increasing rotation durations, observers consistently perceive the transient as large rotational jumps in the direction opposite to rotation direction (backward jumps). We first show that accumulated motion information is updated spatiotopically across saccades. Then, we show that this accumulated information is readily available after a saccade, immediately biasing postsaccadic perception. The current findings suggest that presaccadic information is used to facilitate postsaccadic perception and are in support of a forward model of transsaccadic perception, aiming at anticipating the consequences of eye movements and operating within the narrow perisaccadic time window.
Carrier Localization Effects in InGaN/GaN Multiple-Quantum-Wells LED Nanowires: Luminescence Quantum Efficiency Improvement and “Negative” Thermal Activation Energy
Authors: Bao Wei , Su Zhicheng , Zheng Changcheng , Ning Jiqiang , Xu Shijie
Published: September 2016

Two-dimensional InGaN/GaN multiple-quantum-wells (MQW) LED structure was nanotextured into quasi-one-dimensional nanowires (NWs) with different average diameters with a combination approach of Ni nanoislands as mask + dry etching. Such nanotexturing bring out several appealing effects including deeper localization of carriers and significant improvement in quantum efficiency (e.g., from 4.76% of the planar MQW structure to 12.5% of the 160 nm MQW NWs) of light emission in the whole interested temperature range from 4 K to 300 K. With the aid of localized-state ensemble (LSE) luminescence model, the photoluminescence spectra of the samples are quantitatively interpreted in the entire temperature range. In terms of distinctive temperature dependence of photoluminescence from these samples, a concept of “negative” thermal activation energy is tentatively proposed for the MQW NWs samples. These findings could lead to a deeper insight into the physical nature of localization and luminescence mechanism of excitons in InGaN/GaN nanowires.
Observation of orbital two-channel Kondo effect in a ferromagnetic L10-MnGa film
Authors: Zhu Lijun , Woltersdorf Georg , Zhao Jianhua
Published: September 2016

The experimental existence and stability of the fixed point of the two-channel Kondo (2CK) effect displaying exotic non-Fermi liquid physics have been buried in persistent confusion despite the intensive theoretical and experimental efforts in past three decades. Here we report an experimental realization of the two-level system resonant scattering-induced orbital 2CK effect in a ferromagnetic L10-MnGa film, which is signified by a magnetic field-independent resistivity upturn that has a logarithmic and a square-root temperature dependence beyond and below the Kondo temperature of ~14.5 K, respectively. Our results not only evidence the robust existence of orbital 2CK effect even in the presence of strong magnetic fields and long-range ferromagnetic ordering, but also extend the scope of 2CK host materials from nonmagnetic nanoscale point contacts to diffusive conductors of disordered alloys.
Exosomes derived from MSCs ameliorate retinal laser injury partially by inhibition of MCP-1
Authors: Yu Bo , Shao Hui , Su Chang , Jiang Yuanfeng , Chen Xiteng , Bai Lingling , Zhang Yan , Li Qiutang , Zhang Xiaomin , Li Xiaorong
Published: September 2016

Although accumulated evidence supports the notion that mesenchymal stem cells (MSCs) act in a paracrine manner, the mechanisms are still not fully understood. Recently, MSC-derived exosomes (MSC-Exos), a type of microvesicle released from MSCs, were thought to carry functional proteins and RNAs to recipient cells and play therapeutic roles. In the present study, we intravitreally injected MSCs derived from either mouse adipose tissue or human umbilical cord and their exosomes to observe and compare their functions in a mouse model of laser-induced retinal injury. We found that both MSCs and their exosomes reduced damage, inhibited apoptosis and suppressed inflammatory responses to obtain better visual function to nearly the same extent in vivo. Obvious down-regulation of monocyte chemotactic protein (MCP)-1 in the retina was found after MSC-Exos injection. In vitro, MSC-Exos also down-regulated MCP-1 mRNA expression in primarily cultured retinal cells after thermal injury. It was further demonstrated that intravitreal injection of an MCP-1-neutralizing antibody promoted the recovery of retinal laser injury, whereas the therapeutic effect of exosomes was abolished when MSC-Exos and MCP-1 were administrated simultaneously. Collectively, these results suggest that MSC-Exos ameliorate laser-induced retinal injury partially through down-regulation of MCP-1.
Angiotensin-(1–7) abrogates angiotensin II-induced proliferation, migration and inflammation in VSMCs through inactivation of ROS-mediated PI3K/Akt and MAPK/ERK signaling pathways
Authors: Zhang Feng , Ren Xingsheng , Zhao Mingxia , Zhou Bing , Han Ying
Published: September 2016

The proliferation, migration and inflammation of vascular smooth muscle cells (VSMCs) contribute to the pathogenesis and progression of several cardiovascular diseases such as atherosclerosis and hypertension. Angiotensin (Ang)-(1–7) and Ang II are identified to be involved in regulating cardiovascular activity. The present study is designed to determine the interaction between Ang-(1–7) and Ang II on VSMCs proliferation, migration and inflammation as well as their underlying mechanisms. We found that Ang-(1–7) significantly suppressed the positive effects of Ang II on VSMCs proliferation, migration and inflammation, as well as on induction of the phosphorylation of Akt and ERK1/2 and increase of superoxide anion level and NAD(P)H oxidase activity in VSMCs, whereas Ang-(1–7) alone had no significant effects. This inhibitory effects of Ang-(1–7) were abolished by Mas receptor antagonist A-779. In addition, Ang II type 1 (AT1) receptor antagonist losartan, but not A-779, abolished Ang II induced VSMCs proliferation, migration and inflammation responses. Furthermore, superoxide anion scavenger N-acetyl-L-cysteine (NAC) or NAD(P)H oxidase inhibitor apocynin inhibited Ang II-induced activation of Akt and ERK1/2 signaling. These results indicate that Ang-(1–7) antagonizes the Ang II-induced VSMC proliferation, migration and inflammation through activation of Mas receptor and then suppression of ROS-dependent PI3K/Akt and MAPK/ERK signaling pathways.
4D–π–1A type β-substituted ZnII-porphyrins: ideal green sensitizers for building-integrated photovoltaics
Authors: Covezzi A. , Orbelli Biroli A. , Tessore F. , Forni A. , Marinotto D. , Biagini P. , Di Carlo G. , Pizzotti M.
Published: September 2016

Green and easy to prepare 4D–π–1A type β-substituted ZnII-porphyrins with enhanced push–pull character.
Formate adsorption on Pt nanoparticles during formic acid electro-oxidation: insights from in situ infrared spectroscopy
Authors: McPherson Ian J. , Ash Philip A. , Jacobs Robert M. J. , Vincent Kylie A.
Published: September 2016

Adsorbed formate is observed on a supported Pt nanoparticle for the first time during formic acid electro-oxidation.
A ligation-based loop-mediated isothermal amplification (ligation-LAMP) strategy for highly selective microRNA detection
Authors: Du Wenfang , Lv Mengmei , Li Junjie , Yu Ruqin , Jiang Jianhui
Published: September 2016

A novel ligation-based loop-mediated isothermal amplification (ligation-LAMP) method has been developed for sensitive and selective detection of microRNA.
In vivo near-infrared and Cerenkov luminescence imaging of amyloid-β deposits in the brain: a fluorinated small molecule used for dual-modality imaging
Authors: Fu Hualong , Peng Cheng , Liang Zhigang , Dai Jiapei , Liu Boli , Cui Mengchao
Published: September 2016

Three fluorinated (19F or 18F) small molecules were evaluated as fluorescent or radiolabeled probes for Aβ deposits in the brain.
Mass spectrometry-based assay for the rapid detection of thiol-containing natural products
Authors: Capehart Stacy L. , Carlson Erin E.
Published: September 2016

To expedite discovery of thiol-containing compounds, we devised a selective solid-supported reagent for their immobilization, followed by cleavage of a photocleavable linker to yield stable natural product conjugates for direct detection by mass spectrometry.
Correction: Highly efficient photoelectrochemical water splitting by a hybrid tandem perovskite solar cell
Authors: Bin Abd. Rashid , Yusoff Mohd , Jang Jin
Published: September 2016

Correction for ‘Highly efficient photoelectrochemical water splitting by a hybrid tandem perovskite solar cell’ by Abd. Rashid Bin et al., Chem. Commun., 2016, 52, 5824–5827.
Ultrafast multiexponential electron injection dynamics at a dye and ZnO QD interface: a combined spectroscopic and first principles study
Authors: Kumar Pushpendra , Pal Suman Kalyan
Published: September 2016

Multiexponential electron injection across a dye and ZnO quantum dot (QD) interface has been demonstrated using a combination of steady-state, time-resolved fluorescence and femtosecond transient absorption (TA) spectroscopies.
Spin-state energies of heme-related models from spin-flip TDDFT calculations
Authors: Zhao Hui , Fang Changfeng , Gao Jun , Liu Chengbu
Published: September 2016

The spin-state energies of heme-related models were calculated by using the spin-flip TDDFT method avoiding spin contamination.
Neural network molecular dynamics simulations of solid–liquid interfaces: water at low-index copper surfaces
Authors: Natarajan Suresh Kondati , Behler Jörg
Published: September 2016

Molecular dynamics simulation of the water–copper interface have been carried out using high-dimensional neural network potential based on density functional theory.