bluuebunny/crossref_metadata_2025 huggingface dataset:
Flexible control of positive and negative electrocaloric effects under multiple fields for a giant improvement of cooling capacity
Authors: Li Jianting , Qin Shiqiang , Bai Yang , Li Junjie , Qiao Lijie
Published: August 2017

This paper demonstrated the flexible control of positive and negative electrocaloric effects (ECEs) in ⟨001⟩-Pb(Mg1/3Nb2/3)0.7Ti0.3O3 single crystal, and a dual cooling cycle is proposed using their combination to improve cooling capacity. The ECE exhibits a complex evolution of positive-negative-positive within 20–140 °C, where the negative ECE originates from the electric field-induced transition from rhombohedral phase to high-symmetric tetragonal phase. Since the coexistence of different ECEs at some temperatures, the positive and negative ECEs alternately appear in neighboring cycles under proper applied fields, i.e., dual cooling. A significant improvement of ∼150% in cooling capacity is directly characterized by the isothermal heat flow measurement.
Group analysis of general Burgers–Korteweg–de Vries equations
Authors: Opanasenko Stanislav , Bihlo Alexander , Popovych Roman O.
Published: August 2017

The complete group classification problem for the class of (1+1)-dimensional rth order general variable-coefficient Burgers–Korteweg–de Vries equations is solved for arbitrary values of r greater than or equal to two. We find the equivalence groupoids of this class and its various subclasses obtained by gauging equation coefficients with equivalence transformations. Showing that this class and certain gauged subclasses are normalized in the usual sense, we reduce the complete group classification problem for the entire class to that for the selected maximally gauged subclass, and it is the latter problem that is solved efficiently using the algebraic method of group classification. Similar studies are carried out for the two subclasses of equations with coefficients depending at most on the time or space variable, respectively. Applying an original technique, we classify Lie reductions of equations from the class under consideration with respect to its equivalence group. Studying alternative gauges for equation coefficients with equivalence transformations allows us not only to justify the choice of the most appropriate gauge for the group classification but also to construct for the first time classes of differential equations with nontrivial generalized equivalence group such that equivalence-transformation components corresponding to equation variables locally depend on nonconstant arbitrary elements of the class. For the subclass of equations with coefficients depending at most on the time variable, which is normalized in the extended generalized sense, we explicitly construct its extended generalized equivalence group in a rigorous way. The new notion of effective generalized equivalence group is introduced.
Analytical gradients for tensor hyper-contracted MP2 and SOS-MP2 on graphical processing units
Authors: Song Chenchen , Martínez Todd J.
Published: August 2017

Analytic energy gradients for tensor hyper-contraction (THC) are derived and implemented for second-order Møller-Plesset perturbation theory (MP2), with and without the scaled-opposite-spin (SOS)-MP2 approximation. By exploiting the THC factorization, the formal scaling of MP2 and SOS-MP2 gradient calculations with respect to system size is reduced to quartic and cubic, respectively. An efficient implementation has been developed that utilizes both graphics processing units and sparse tensor techniques exploiting spatial sparsity of the atomic orbitals. THC-MP2 has been applied to both geometry optimization and ab initio molecular dynamics (AIMD) simulations. The resulting energy conservation in micro-canonical AIMD demonstrates that the implementation provides accurate nuclear gradients with respect to the THC-MP2 potential energy surfaces.
Evaluation of flamelet/progress variable model for laminar pulverized coal combustion
Authors: Wen Xu , Wang Haiou , Luo Yujuan , Luo Kun , Fan Jianren
Published: August 2017

In the present work, the flamelet/progress variable (FPV) approach based on two mixture fractions is formulated for pulverized coal combustion and then evaluated in laminar counterflow coal flames under different operating conditions through both a priori and a posteriori analyses. Two mixture fractions, Zvol and Zchar, are defined to characterize the mixing between the oxidizer and the volatile matter/char reaction products. A coordinate transformation is conducted to map the flamelet solutions from a unit triangle space (Zvol, Zchar) to a unit square space (Z, X) so that a more stable solution can be achieved. To consider the heat transfers between the coal particle phase and the gas phase, the total enthalpy is introduced as an additional manifold. As a result, the thermo-chemical quantities are parameterized as a function of the mixture fraction Z, the mixing parameter X, the normalized total enthalpy Hnorm, and the reaction progress variable YPV. The validity of the flamelet chemtable and the selected trajectory variables is first evaluated in a priori tests by comparing the tabulated quantities with the results obtained from numerical simulations with detailed chemistry. The comparisons show that the major species mass fractions can be predicted by the FPV approach in all combustion regions for all operating conditions, while the CO and H2 mass fractions are over-predicted in the premixed flame reaction zone. The a posteriori study shows that overall good agreement between the FPV results and those obtained from detailed chemistry simulations can be achieved, although the coal particle ignition is predicted to be slightly earlier. Overall, the validity of the FPV approach for laminar pulverized coal combustion is confirmed and its performance in turbulent pulverized coal combustion will be tested in future work.
Effect of thickness on the maximum potential drop of current collectors
Authors: Campillo-Robles Jose Miguel , Artetxe Xabier , del Teso Sánchez Karmele
Published: August 2017

The basic principle for achieving high-power capability on an electrochemical energy storage cell is minimizing the overall resistance. The resistance due to current collecting systems has not received sufficient attention in the past, presumably because it was not considered of significance for low-power batteries and supercapacitors. However, the necessity of high-power cells has reduced other sources of the inner resistance, and the current collector potential drop has become more important. Moreover, the miniaturization of energy storage devices could increase the ohmic loses in current collectors. In this work, we have developed an electrical model to assess the effect of the current collector thickness on the maximum potential drop. We have found that the thickness of current collectors is a critical parameter that can increase the maximum potential drop drastically. Indeed, the maximum potential drop of current collectors remains almost constant for thicknesses greater than 500 μm, but below this value, there is an inverse relationship between the maximum potential drop and the thickness. We have also analyzed the effect of the material and tab position in the maximum potential drop.
A generalization of gauge invariance
Authors: Grigore Dan-Radu
Published: August 2017

We consider perturbative quantum field theory in the causal framework. Gauge invariance is, in this framework, an identity involving chronological products of the interaction Lagrangian; it expresses the fact that the scattering matrix must leave invariant the sub-space of physical states. We are interested in generalizations of such identity involving Wick sub-monomials of the interaction Lagrangian. The analysis can be performed by direct computation in the lower orders of perturbation theory; guided by these computations, we conjecture a generalization for arbitrary orders.
First-principles and molecular dynamics study of thermoelectric transport properties of N-type silicon-based superlattice-nanocrystalline heterostructures
Authors: Zhou Yanguang , Gong Xiaojing , Xu Ben , Hu Ming
Published: August 2017

Electrical and thermal transport in silicon germanium superlattice nanostructures has received extensive attention from scientists for understanding carrier properties at the nanoscale, and the figure-of-merit (ZT) reported in such structures has inspired engineers to develop cost-effective waste heat recovery systems. In this paper, the thermoelectric transport properties of the silicon-based superlattice- and anti-superlattice-nanocrystalline heterostructures are systematically studied by first-principles and molecular dynamics simulations combined with the Boltzmann transport theory. The thermal conductivity, which is thought to be the essential bottleneck for bulk crystalline Si to gain a high ZT value, of such structures is found to be reduced by two orders of magnitude and reaches a level far below the amorphous limit of Si. This is achieved due to the extremely strong phonon-boundary scattering at both grain boundaries and Si-Ge interfaces, which will lead to the phonon mean free path being much smaller than the grain size (Casmir limit): for instance, the dominant phonons are in range of 0.5 to 3 nm for the heterostructures with a grain size of around 8 nm. Meanwhile, the power factor can be preserved at the level comparable to bulk crystalline because of the quantum confinement effect, which resulted from the conduction band minima converge, reduction of band gap, and the short mean free path of carriers. As a result, the ZT of such superlattice based nanomembranes can reach around 0.3 at room temperature, which is two orders of magnitude higher than the bulk crystalline case. The corresponding bulk superlattice-nanocrystalline heterostructures possess a ZT value of 0.5 at room temperature, which is superior to all other bulk silicon-based thermoelectrics. Our results here show that nanostructuring the superlattice structure can further decrease the thermal conductivity while keeping the electrical transport properties at the bulk comparable level, and provides a new strategy for enhancing the thermoelectric performance of the silicon-based nanostructures.
Effects of ultrathin coating on the tensile behavior of nanoporous gold
Authors: Yildiz Yunus Onur , Kirca Mesut
Published: August 2017

In this study, the mechanical properties of nanoporous gold (np-Au) coated with different ultrathin metallic materials (i.e., platinum and silver) are studied through molecular dynamics simulations. A new atomistic modelling technique, which is based on the Voronoi tessellation method providing periodic atomistic specimens, is used for the geometric representation of np-Au structure. Three different coating thickness values are used to examine the role of thickness on the coating performance under tensile loading at a constant strain rate. Several parameters, including Young's modulus, yield, and ultimate strengths, are utilized to compare the mechanical characteristics of coated and uncoated np-Au specimens. Moreover, adaptive common neighbor analyses are performed on the specimens for the purpose of understanding the deformation mechanisms of coated and uncoated nanoporous specimens comprehensively by monitoring the microstructural evolution of the crystal structure of the specimens within the deformation process. As a main finding from the simulations, it is observed that the mechanical properties of np-Au are improved by coating independently of the coating material type. However, enhancements on the yield and ultimate strengths maintained by platinum coating are greater than those provided by the silver coating.
Multimode time-dependent gyrotron equations for different time scales
Authors: Dumbrajs O. , Kalis H.
Published: August 2017

Development of gyrotrons requires careful understanding of different regimes of gyrotron oscillations. For a long time, the gyrotron theory was developed assuming that the transit time of electrons through the interaction space is much shorter than the cavity fill time. Correspondingly, it was assumed that during this transit time, the amplitude of microwave oscillations remains constant. However, there are situations when this assumption is not fulfilled, or is marginally fulfilled. In such cases, a different mathematical formalism has to be used. The present paper generalizes the new formalism to the multi mode case. The particular example considered indicates that in some cases the results obtained by means of the old and the new formalism differ significantly.
Fast detection and low power hydrogen sensor using edge-oriented vertically aligned 3-D network of MoS2 flakes at room temperature
Authors: Agrawal A. V. , Kumar R. , Venkatesan S. , Zakhidov A. , Zhu Z. , Bao Jiming , Kumar Mahesh , Kumar Mukesh
Published: August 2017

The increased usage of hydrogen as a next generation clean fuel strongly demands the parallel development of room temperature and low power hydrogen sensors for their safety operation. In this work, we report strong evidence for preferential hydrogen adsorption at edge-sites in an edge oriented vertically aligned 3-D network of MoS2 flakes at room temperature. The vertically aligned edge-oriented MoS2 flakes were synthesised by a modified CVD process on a SiO2/Si substrate and confirmed by Scanning Electron Microscopy. Raman spectroscopy and PL spectroscopy reveal the signature of few-layer MoS2 flakes in the sample. The sensor's performance was tested from room temperature to 150 °C for 1% hydrogen concentration. The device shows a fast response of 14.3 s even at room temperature. The sensitivity of the device strongly depends on temperature and increases from ∼1% to ∼11% as temperature increases. A detail hydrogen sensing mechanism was proposed based on the preferential hydrogen adsorption at MoS2 edge sites. The proposed gas sensing mechanism was verified by depositing ∼2–3 nm of ZnO on top of the MoS2 flakes that partially passivated the edge sites. We found a decrease in the relative response of MoS2-ZnO hybrid structures. This study provides a strong experimental evidence for the role of MoS2 edge-sites in the fast hydrogen sensing and a step closer towards room temperature, low power (0.3 mW), hydrogen sensor development.
Mouse double minute homologue 2 (MDM2) downregulation by miR-661 impairs human endometrial epithelial cell adhesive capacity
Authors: Winship Amy , Ton Amanda , Van Sinderen Michelle , Menkhorst Ellen , Rainczuk Katarzyna , Griffiths Meaghan , Cuman Carly , Dimitriadis Evdokia
Published: August 2017

Human blastocysts that fail to implant following IVF secrete elevated levels of miR-661, which is taken up by primary human endometrial epithelial cells (HEECs) and impairs their adhesive capability. MicroRNA miR-661 downregulates mouse double minute homologue 2 (MDM2) and MDM4 in other epithelial cell types to activate p53; however, this has not been examined in the endometrium. In this study MDM2 protein was detected in the luminal epithelium of the endometrium, the site of blastocyst attachment, during the mid secretory receptive phase of the menstrual cycle. The effects of miR-661 on gene expression in and adhesion of endometrial cells was also examined. MiR-661 overexpression consistently downregulated MDM2 but not MDM4 or p53 gene expression in the Ishikawa endometrial epithelial cell line and primary HEEC. Adhesion assays were performed on the real-time monitoring xCELLigence system and by co-culture using Ishikawa cells and HEECs with HTR8/SVneo trophoblast spheroids. Targeted siRNA-mediated knockdown of MDM2 in endometrial epithelial cells reduced Ishikawa cell adhesion (P < 0.001) and also reduced HTR8/SVneo trophoblast spheroid adhesion to Ishikawa cells (P < 0.05) and HEECs (P < 0.05). MDM2 overexpression using recombinant protein treatment resulted in enhanced HTR8/SVneo trophoblast spheroid adhesion to Ishikawa cells (P < 0.01) and HEECs (P < 0.05). This study highlights a potential new mechanism by which human blastocyst-secreted miR-661 reduces endometrial epithelial cell adhesion; via downregulation of MDM2. These findings suggest that MDM2 contributes to endometrial–blastocyst adhesion, implantation and infertility in women.
Public willingness to participate in actions for crow management
Authors: Špur Natalija , Pokorny Boštjan , Šorgo Andrej
Published: August 2017

Context
Large-scale human modification of the environment has caused an overall loss of biodiversity; some species, such as crows, do benefit from these changes. Increased crow numbers in Slovenia in the past two decades have caused one of the main human–wildlife conflicts. To reduce these conflicts, successful and effective wildlife management is needed that is rooted in an evaluation of general public opinions and attitudes towards action.

Aims
The purpose of the present study was to identify factors that affect the willingness of the public to participate in actions for crow management. With knowledge about the factors that affect the willingness to participate in management actions, we can enhance public intention and behaviour.

Methods
A research model based on variables from a public survey was set up and tested with ordinal regression analysis.

Key results
The willingness to participate in crow management was influenced by (1) attitudes towards action, (2) interest in crows and conflicts in interaction with the moderator variables of education level or place of residence, (3) perceived behavioural control, (4) fear towards damage caused by crows, and (5) trust in experts in with the moderator variables of gender, education level, or utilitarian behaviour.

Conclusions
Public do not possess sufficient competences for crow management. With additional information and awareness, they could decide more clearly about their participation in management.

Implications
To increase the number of participants in actions, we need to educate the public about critical skills and competencies, provide explanations why some actions are effective and feasible, and convey the importance of public participation. With low confidence about their competences and low, or even no, trust in decision-makers, the willingness to participate was found to decrease.
Reputation offsets trust judgments based on social biases among Airbnb users
Authors: Abrahao Bruno , Parigi Paolo , Gupta Alok , Cook Karen S.
Published: August 2017

Significance

We investigate the extent to which artificial features engineered by sharing-economy platforms, such as reputation systems, can be used to override people’s tendency to base judgments of trustworthiness on social biases, such as to trust others who are similar (i.e., homophily). To this end, we engaged 8,906 users of Airbnb as volunteers in an online experiment. We demonstrate that homophily based on several demographic characteristics is a relatively weak driver of trust. In fact, having high reputation is enough to counteract homophily. Using Airbnb data, we present evidence that the effects we found experimentally are at work in the actual platform. Lastly, we found an inverse relationship between risk aversion and trust in those with positive reputations.
Petroleum dynamics in the sea and influence of subsea dispersant injection during
Deepwater Horizon
Authors: Gros Jonas , Socolofsky Scott A. , Dissanayake Anusha L. , Jun Inok , Zhao Lin , Boufadel Michel C. , Reddy Christopher M. , Arey J. Samuel
Published: August 2017

Significance

Environmental risks posed by deep-sea petroleum releases are difficult to predict and assess. We developed a physical model of the buoyant jet of petroleum liquid droplets and gas bubbles gushing into the deep sea, coupled with simulated liquid–gas equilibria and aqueous dissolution kinetics of petroleum compounds, for the 2010
Deepwater Horizon
disaster. Simulation results are validated by comparisons with extensive observation data collected in the sea and atmosphere near the release site. Simulations predict that chemical dispersant, injected at the wellhead to mitigate environmental harm, increased the entrapment of volatile compounds in the deep sea and thereby improved air quality at the sea surface. Subsea dispersant injection thus lowered human health risks and accelerated response during the intervention.
Shear force-based genetic screen reveals negative regulators of cell adhesion and protrusive activity
Authors: Lampert Thomas J. , Kamprad Nadine , Edwards Marc , Borleis Jane , Watson Ayende J. , Tarantola Marco , Devreotes Peter N.
Published: August 2017

Significance

We report a forward genetic screen to identify genes involved in cell adhesion and motility. Cells with mutations in these genes have increased adhesion, flattened morphology, and decreased motility. The mutants display increased cytoskeletal and signal transduction network activity suggesting that these genes are negative regulators. The GFP-tagged localization of these proteins shows the remarkable diversity in the regulation of these cell behaviors. Several of the identified proteins have strong homologs throughout metazoans and have relevance to human disease. Because many of the resulting mutant phenotypes are similar to those of cells lacking PTEN or expressing active Ras GTPases, these gene families are promising cancer targets in humans. Better understanding of these pathways holds the possibility for therapeutic intervention.
Compounding effects of sea level rise and fluvial flooding
Authors: Moftakhari Hamed R. , Salvadori Gianfausto , AghaKouchak Amir , Sanders Brett F. , Matthew Richard A.
Published: August 2017

Significance

Population and assets in coastal regions are threatened by both oceanic and fluvial flooding hazards. Common flood hazard assessment practices typically focus on one flood driver at a time and ignore potential compounding impacts. Here we outline a unique bivariate flood hazard assessment framework that accounts for the interactions between a primary oceanic flooding hazard, coastal water level, and fluvial flooding hazards. Using the notion of “failure probability,” we also assess coastal flood hazard under different future sea level rise scenarios. The results show that, in a warming climate, future sea level rise not only increases the failure probability, but also exacerbates the compounding effects of flood drivers.
Dynamics of nitric oxide controlled by protein complex in bacterial system
Authors: Terasaka Erina , Yamada Kenta , Wang Po-Hung , Hosokawa Kanta , Yamagiwa Raika , Matsumoto Kimi , Ishii Shoko , Mori Takaharu , Yagi Kiyoshi , Sawai Hitomi , Arai Hiroyuki , Sugimoto Hiroshi , Sugita Yuji , Shiro Yoshitsugu , Tosha Takehiko
Published: August 2017

Significance

Denitrification, a form of microbial anaerobic respiration where nitrate is sequentially reduced (NO
3
−
→ NO
2
−
→ NO → N
2
O → N
2
) is environmentally, biologically, and chemically interesting, as well as being medically significant. Some pathogenic bacteria, including the major opportunistic pathogen
Pseudomonas aeruginosa
, can survive in oxygen-limited environments such as biofilms and the lungs of cystic fibrosis patients, owing to denitrification. The current proposal of a complex formation of NO-generating nitrite reductase and NO-decomposing nitric oxide reductase for rapid elimination of NO, a cytotoxic intermediate, in denitrification contributes to further understanding of denitrification and to the design of antimicrobial drugs. This paper also provides an idea of how biological systems control the dynamics of cytotoxic diffusible compounds such as NO in cells.
Distribution of lifetime nursing home use and of out‐of‐pocket spending
Authors: Hurd Michael D. , Michaud Pierre‐Carl , Rohwedder Susann
Published: August 2017

Significance

Although it is important to know the annual costs and use of nursing homes, for individuals and households, it is also important to know expected lifetime costs and use of nursing homes; that is, how much they will use nursing homes and how much might spend over their lifetimes. They need this information in deciding how much to save and whether to purchase insurance that will pay for nursing home use. By following individuals over many years as they progress to advanced old age, we estimated how many days individuals will spend in nursing homes and how much they will spend out-of-pocket.
ER stress and distinct outputs of the IRE1α RNase control proliferation and senescence in response to oncogenic Ras
Authors: Blazanin Nicholas , Son Jeongin , Craig-Lucas Alayna B. , John Christian L. , Breech Kyle J. , Podolsky Michael A. , Glick Adam B.
Published: August 2017

Significance

Inositol requiring enzyme 1α (IRE1α) is a mediator of the unfolded protein response that determines adaptation or cell death in response to endoplasmic reticulum (ER) stress through its distinct endoribonuclease (RNase) activities of
Xbp1
splicing and mRNA decay, but its role in cancer is poorly understood. In normal epithelial cells, we find that Ras oncogene-induced proliferation and senescence are directly linked to IRE1α activation. Proliferation requires
Xbp1
splicing and ER stress, while IRE1α-catalyzed degradation of
Id1
mRNA drives senescence in conjunction with reduced ER stress. Thus, we propose that oncogene and ER stress regulation of the IRE1α RNase dictates tumor promotion or suppression in Ras-driven cancers.
NLRP3
mutation and cochlear autoinflammation cause syndromic and nonsyndromic hearing loss DFNA34 responsive to anakinra therapy
Authors: Nakanishi Hiroshi , Kawashima Yoshiyuki , Kurima Kiyoto , Chae Jae Jin , Ross Astin M. , Pinto-Patarroyo Gineth , Patel Seema K. , Muskett Julie A. , Ratay Jessica S. , Chattaraj Parna , Park Yong Hwan , Grevich Sriharsha , Brewer Carmen C. , Hoa Michael , Kim H. Jeffrey , Butman John A. , Broderick Lori , Hoffman Hal M. , Aksentijevich Ivona , Kastner Daniel L. , Goldbach-Mansky Raphaela , Griffith Andrew J.
Published: August 2017

Significance

This study identifies a mutation in the
NLRP3
gene that causes sensorineural hearing loss in human patients.
NLRP3
encodes a protein important for innate immunity, secretion of the potent cytokine IL-1β, and inflammation. The hearing loss in three affected members of one family improved or completely resolved after treatment with IL-1β blockade therapy. This study shows that the mouse
Nlrp3
gene is expressed in immune macrophage-like cells throughout the inner ear, which can be activated to release the potent cytokine IL-1β. These observations suggest that mutations of
NLRP3
may cause hearing loss by local autoinflammation within the inner ear. This mechanism could underlie a variety of hearing-loss disorders of unknown etiology that might respond to IL-1β blockade therapy.
Evolutionary consequences of multidriver environmental change in an aquatic primary producer
Authors: Brennan Georgina L. , Colegrave Nick , Collins Sinéad
Published: August 2017

Significance

Our understanding of how primary producers at the base of aquatic ecosystems respond to complex environmental change currently depends on studies using few environmental drivers, or scenarios where drivers covary. However, we lack a general understanding of evolution in multidriver environments. We evolve a microbial primary producer in 96 different multidriver environments and find that evolutionary responses in growth are largely driven by a few drivers but that the intensity of selection is, on average, higher in multidriver environments. Functional traits (cell size, chlorophyll content) often revert to ancestral values during adaptation in multidriver environments. This expands the framework for understanding how microbial primary producers evolve under global change and the potential ramifications for their function in aquatic ecosystems.
North–south polarization of European electricity consumption under future warming
Authors: Wenz Leonie , Levermann Anders , Auffhammer Maximilian
Published: August 2017

Significance

We statistically analyze 2006–2012 high-frequency temperature and electricity load data from 35 European countries to compute climate change impacts on electricity demand until 2100. Extrapolating countries’ load responses to temperature beyond currently experienced climate, we find a future polarization of both peak load and electricity consumption in Europe. Specifically, while total European consumption remains constant under future warming, we project significant increases in the south, decreases in the north, and a shift of seasonal peak load from winter to summer for 19 countries. This changing spatial and temporal pattern of consumption and peak load has important implications for the build-out of transmission infrastructure, the construction of peak-generating capacity, and the design of energy-efficiency policy and storage capacity.
Dendritic transport of tick-borne flavivirus RNA by neuronal granules affects development of neurological disease
Authors: Hirano Minato , Muto Memi , Sakai Mizuki , Kondo Hirofumi , Kobayashi Shintaro , Kariwa Hiroaki , Yoshii Kentaro
Published: August 2017

Significance

Flaviviruses represent a significant threat to public health worldwide, and several cause severe neurological disease in humans and animals. However, no specific treatment has been developed, due to the lack of information about their detailed pathogenic mechanisms. In the current study, we reveal that the transport of viral RNA of tick-borne flavivirus in neuronal dendrites is involved in the development of neurological disease. The virus hijacked the transport system of host mRNA in dendrites, which is important for neuronal functions such as neurogenesis and the plasticity of the synaptic communication. Our finding of this unique virus–host interaction will promote the study of neurodegenerative diseases caused by disruption of dendritic mRNA transport and the development of their treatment.
Increasing atmospheric humidity and CO
2
concentration alleviate forest mortality risk
Authors: Liu Yanlan , Parolari Anthony J. , Kumar Mukesh , Huang Cheng-Wei , Katul Gabriel G. , Porporato Amilcare
Published: August 2017

Significance

The significance of forest mortality on ecosystem services, and water, carbon, and nutrient cycling is indubitable. While there is a general agreement that climate change-induced heat and drought stress is expected to intensify forest mortality, the concurrent influence of changes in atmospheric humidity and CO
2
concentration remains unclear. Here, the response of mortality risk to projected climate change is evaluated in 13 biomes across the globe. Our results show that increasing specific humidity and CO
2
concentration partially offset the intensification of risk by changing precipitation and air temperature. The risk response is also mediated by plant hydraulic traits. The study provides a mechanistic foundation for estimating future responses of forest mortality risk, which can facilitate ecosystem management.
Neutral high-generation phosphorus dendrimers inhibit macrophage-mediated inflammatory response in vitro and in vivo
Authors: Posadas I. , Romero-Castillo L. , El Brahmi N. , Manzanares D. , Mignani S. , Majoral J.-P. , Ceña V.
Published: August 2017

Significance

Inflammation is a relevant part of the physiological response of the immune system to fight infectious diseases. However, excessive inflammation can also participate in the pathogenesis of several diseases. To open new avenues to treat the negative aspects of inflammation, we have used biocompatible nanoparticles, neutrally charged G3-G4 phosphorus dendrimers, which are not toxic and have good solubility and chemical stability in aqueous solutions. These nanoparticles are very efficient, in vitro and in vivo, to tackle the inflammatory response produced by different agents. In addition, the high number of chemically modifiable terminal groups on the surface of these nanodevices opens the high possibility of incorporating into them specific therapeutic groups which provide multifunctional therapeutic abilities.
Direct single-molecule measurements of phycocyanobilin photophysics in monomeric C-phycocyanin
Authors: Squires Allison H. , Moerner W. E.
Published: August 2017

Significance

The efficiency and adaptability of photosynthetic antenna systems in harvesting solar energy can be ultimately traced to their nanoscale organization. By monitoring the fluorescence emission from single photosynthetic antenna proteins in free solution over long timescales, we directly observed transitions among many distinct photophysical states exhibiting different flows of energy transfer among the embedded photosensitive pigments. We show that these states are well-described by a simple physical model, which allows us to identify and characterize the properties of individual chromophores and reveals surprising heterogeneity and quenching behavior that is not predicted by bulk studies.
Knots can impair protein degradation by ATP-dependent proteases
Authors: San Martín Álvaro , Rodriguez-Aliaga Piere , Molina José Alejandro , Martin Andreas , Bustamante Carlos , Baez Mauricio
Published: August 2017

Significance

AAA+ proteases are ring-shaped machines with a central narrow pore used to translocate protein substrates into a proteolytic chamber. Knotted proteins, however, may block the narrow pore by formation of an incompressible tight knot. Here, we determined how the archetypal AAA+ ClpXP protease degrades a protein substrate containing a trefoil knot. A trefoil knot is degraded quickly by ClpXP but not when it is fused to GFP placed downstream of the knot. Specifically, ClpXP releases partially degraded products when a tight knot is buttressed against GFP. Furthermore, degradation of substrates harboring linkers of different lengths between the knot and GFP allowed us to explore the dynamics of knot tightening and sliding and to postulate a new biological role for knotted proteins.
Mechanisms of ovipositor insertion and steering of a parasitic wasp
Authors: Cerkvenik Uroš , van de Straat Bram , Gussekloo Sander W. S. , van Leeuwen Johan L.
Published: August 2017

Significance

Using slender probes to drill through solids is challenging, but desirable, due to minimal disturbances of the substrate. Parasitic wasps drill into solid substrates and lay eggs in hosts hidden within using slender probes and are therefore a good model for studying mechanical challenges associated with this process. We show that wasps are able to probe in any direction with respect to their body orientation and use two methods of insertion. One of the methods implies a minimal net pushing force during drilling. Steering was achieved by adjusting the asymmetry of the probe’s distal end. Knowledge on probing mechanisms of wasps is important for the understanding of the hymenopteran evolution and for the development of minimally invasive steerable probes.
5-hydroxymethylcytosine accumulation in postmitotic neurons results in functional demethylation of expressed genes
Authors: Mellén Marian , Ayata Pinar , Heintz Nathaniel
Published: August 2017

Significance

The main insight from this study is that the role of 5-hydroxymethylcytosine (5hmC) in postmitotic neurons is to sculpt the genome occupancy of the very abundant 5-methylcyctosine binding protein 2 (MeCP2). Accumulation of 5hmCG in transcribed genes replaces high-affinity 5mCG binding sites with low-affinity sites, decreasing MeCP2 occupancy over the transcription unit and removing its repressive effect. We refer to this role for 5hmCG as “functional demethylation” because its biochemical effect with respect to MeCP2 is equivalent to chemical demethylation: Loss of high-affinity sites for interaction in the genome. This concept reinforces the roles of 5hmC in demethylation in dividing cells by a mechanism that achieves the same goal without requiring cell division or DNA damage.
Esco1 and Esco2 regulate distinct cohesin functions during cell cycle progression
Authors: Alomer Reem M. , da Silva Eulália M. L. , Chen Jingrong , Piekarz Katarzyna M. , McDonald Katherine , Sansam Courtney G. , Sansam Christopher L. , Rankin Susannah
Published: August 2017

Significance

Sister chromatids are tethered together by the cohesin complex from the time they are made until cell division. Acetylation of the Smc3 subunit of cohesin stabilizes its association with chromatin, and is critical for sister chromatid cohesion. In vertebrates, cohesin is acetylated by two related enzymes: Esco1 and Esco2. We show here that Esco1 is responsible for most Smc3 acetylation but has very little effect on sister cohesion. Esco1 is active throughout the cell cycle, while Esco2 modifies cohesin only during S phase, when sister chromatid cohesion is established. We propose that two distinct pathways regulate cohesin in vertebrates: one is dedicated to cohesion between sister chromatids, and one promotes other functions of cohesin, such as maintenance of chromosome structure.
Plasmon-enhanced light-driven water oxidation by a dye-sensitized photoanode
Authors: Wang Degao , Sherman Benjamin D. , Farnum Byron H. , Sheridan Matthew V. , Marquard Seth L. , Eberhart Michael S. , Dares Christopher J. , Meyer Thomas J.
Published: August 2017

Significance

Dye-sensitized photoelectrosynthesis cells (DSPECs) provide a basis for artificial photosynthesis and solar fuels production. By combining molecular chromophores and catalysts with high surface area, transparent semiconductor electrodes, a DSPEC provides the basis for light-driven conversion of water to O
2
and H
2
or for reduction of CO
2
to carbon-based fuels. The incorporation of plasmonic cubic silver nanoparticles, with a strongly localized surface plasmon absorbance near 450 nm, to a DSPEC photoanode induces a great increase in the efficiency of water oxidation to O
2
at a DSPEC photoanode. The improvement in performance by the molecular components in the photoanode highlights a remarkable advantage for the plasmonic effect in driving the 4e
-
/4H
+
oxidation of water to O
2
in the photoanode.
Investment in secreted enzymes during nutrient-limited growth is utility dependent
Authors: Cezairliyan Brent , Ausubel Frederick M.
Published: August 2017

Significance

Bacteria secrete enzymes into the environment to digest macromolecules into smaller molecules that can be used as nutrients for growth. Secreted enzymes have potential benefits but also entail costs in the form of biomass and energy. How do bacteria determine how much of them to make? Using a system in which nutrient acquisition requires production of secreted enzymes, we infer that bacteria produce secreted signals in proportion to the benefit they would receive from the action of secreted enzymes. Investment in secreted enzymes is adjusted according to the magnitude of those signals. Our model provides a framework that can be applied to bacterial growth in many environments from contaminated food to microbial communities within a host.
Generating gradient germanium nanostructures by shock-induced amorphization and crystallization
Authors: Zhao Shiteng , Kad Bimal , Wehrenberg Christopher E. , Remington Bruce A. , Hahn Eric N. , More Karren L. , Meyers Marc A.
Published: August 2017

Significance

Amorphization and nanocrystallization are two powerful methods to tailor material properties by altering their microstructure without changing the overall chemistry. Using powerful laser-driven shocks, we demonstrate that amorphization and nanocrystallization can be achieved within a time scale that is considerably shorter than other conventional techniques. Our results provide compelling insights into pressure/shear amorphization and propose a route to fabricate gradient semiconducting nanostructures using lasers. Additionally, shear-driven amorphization is demonstrated as the dominant deformation mechanism in this extreme regime.
Phase diagram of URu

2–
x

Fe

x

Si
2
in high magnetic fields
Authors: Ran Sheng , Jeon Inho , Pouse Naveen , Breindel Alexander J. , Kanchanavatee Noravee , Huang Kevin , Gallagher Andrew , Chen Kuan-Wen , Graf David , Baumbach Ryan E. , Singleton John , Maple M. Brian
Published: August 2017

Significance

The mysterious hidden-order (HO) phase in URu
2
Si
2
is intimately related to the large-moment antiferromagnetic (LMAFM) phase that is induced under pressure or upon Fe substitution. In this study, we established the 3D phase diagram of transition temperature (
T
)–magnetic field (
H
)–Fe substituent concentration (
x
), which provides ready access to many of the salient features of the HO and LMAFM phases. We observed reentrance of the hidden-order phase after the LMAFM phase is suppressed by the magnetic field and also established a single relation between the transition temperature and the critical magnetic field for the HO phase, which provides constraints on potential models for the order parameter of the HO phase.
Global metabolic reprogramming of colorectal cancer occurs at adenoma stage and is induced by MYC
Authors: Satoh Kiyotoshi , Yachida Shinichi , Sugimoto Masahiro , Oshima Minoru , Nakagawa Toshitaka , Akamoto Shintaro , Tabata Sho , Saitoh Kaori , Kato Keiko , Sato Saya , Igarashi Kaori , Aizawa Yumi , Kajino-Sakamoto Rie , Kojima Yasushi , Fujishita Teruaki , Enomoto Ayame , Hirayama Akiyoshi , Ishikawa Takamasa , Taketo Makoto Mark , Kushida Yoshio , Haba Reiji , Okano Keiichi , Tomita Masaru , Suzuki Yasuyuki , Fukuda Shinji , Aoki Masahiro , Soga Tomoyoshi
Published: August 2017

Significance

Metabolic reprogramming is one of the hallmarks of cancer. However, the underlying mechanisms that regulate cancer metabolism are poorly understood. Here we performed multiomics-based analysis of paired normal–tumor tissues from patients with colorectal cancer, which revealed that the protooncogene protein MYC regulated global metabolic reprogramming of colorectal cancer by modulating 215 metabolic reactions. Importantly, this metabolic reprogramming occurred in a manner not associated with specific gene mutations in colorectal carcinogenesis. For many years, small-molecule or biologic inhibitors of MYC have been required. Here we demonstrate that knockdown of MYC downstream pyrimidine synthesis genes contributes to the suppression of colorectal cancer cell proliferation similar to MYC, and thus pyrimidine synthesis pathways could be potential targets for colorectal cancer therapy.
Reactive oxygen species extend insect life span using components of the insulin-signaling pathway
Authors: Zhang Xiao-Shuai , Wang Tao , Lin Xian-Wu , Denlinger David L. , Xu Wei-Hua
Published: August 2017

Significance

Oxidative damage is frequently associated with aging and aging-related disease, but, paradoxically, several recent studies have shown that artificial boosts of reactive oxygen species (ROS) can also extend life span in young individuals. Here, we show that physiological levels of ROS promote diapause, thereby extending life span in pupae of the moth
Helicoverpa armigera.
Insect diapause, like the dauer stage of nematodes, is a period of developmental rest that results in a profound extension of life span. ROS appears to contribute to this life span extension by acting through components of the insulin-signaling pathway. Our results thus suggest a new molecular mechanism regulating life span and help to explain the dual nature of ROS action in animals.
tRNAs and proteins use the same import channel for translocation across the mitochondrial outer membrane of trypanosomes
Authors: Niemann Moritz , Harsman Anke , Mani Jan , Peikert Christian D. , Oeljeklaus Silke , Warscheid Bettina , Wagner Richard , Schneider André
Published: August 2017

Significance

In most eukaryotes mitochondrial function requires not only import of proteins but also import of at least some tRNAs. Trypanosomes are extreme in that they lack mitochondrial tRNA genes, and therefore must import all of their mitochondrial tRNAs from the cytosol. Here we show that in trypanosomes both proteins and tRNAs use the same β-barrel protein pore to be translocated across the mitochondrial outer membrane. Moreover, we show that tRNA import can be uncoupled from protein import. Based on these results, we propose the “alternate import model,” in which tRNAs use the same outer membrane import pore as proteins but are imported as naked molecules. The model combines features of the previously proposed “coimport” and “direct import” models.
Corrosion resistance and dynamic anti-icing of superhydrophobic surface on ASW
Authors: Jin Haiyun , Li Zhiwei , Wei Shichao , Nie Shichao , Pan Zehua , Zhang Tao , Gao Naikui
Published: August 2017

The superhydrophobic surface (SHPS) with a contact angle (CA) of 151° and a sliding angle (SA) of 0.5° was successfully fabricated on aluminium stranded wires (ASW) via a simple chemical etching process, and subsequently covered with a fluoroalkylsilane film. The wettability and microstructure of consequent SHPS was characterised by CA/SA, scanning electron microscopy and 3D colour laser scanning microscope, respectively. A simple dynamic icing experimental system was performed. The corrosion resistance and dynamic anti-icing property were also investigated by acid/alkaline solution corrosion and dynamic icing test. The results showed that, due to the combined effect of micro-nano structure, air cushion and capillary. The SHPS possessed great corrosion-resistant and anti-icing properties; moreover, the anti-icing property increased by 68.2% and the starting icing time was delayed by six times, which should be critical to the potential application in industry.
Developmental tasks and well‐being in adolescent elite athletes in comparison with recreational/non‐athletes
Authors: Ohlert Jeannine , Ott Ida
Published: August 2017

Young elite athletes (EA) have to solve the same developmental tasks (DTs) as non‐athletes, even though they spend a lot of time with their sports and have to solve certain sports‐related DTs in addition [Ohlert & Kleinert (2014). Entwicklungsaufgaben jugendlicher Elite‐Handballerinnen und –Handballer [Developmental tasks in adolescent elite handball players]. Zeitschrift für Sportpsychologie, 21(4), 161–172. doi:10.1026/1612‐5010/a000129]. The aim of this study was to find out if this situation leads to a shortfall in certain DTs and, furthermore, to a reduced well‐being in adolescent EA. In total, 185 EA participated in the survey together with 166 recreational/non‐athletes (RA). Participants were between 16 and 19 years old (69% female) and answered questions regarding the relevance of different DTs, their actual progression, satisfaction with their actual progression, and the WHO‐5 measure for well‐being. Compared to the RA group, the EA group reported a different relevance for some DTs. No significant differences were found between the two groups in progression or satisfaction with progression. The stepwise multiple regression resulted in two significant predictors for well‐being in EA: satisfaction with progression in the DTs “to find oneself” and “circle of friends”. For RA, the analysis revealed only satisfaction with progression in “circle of friends” as a significant predictor. Implications are that, at least for this age group, problems with DTs were not detected for the adolescent EA. However, if satisfaction with the own progression in certain DTs is low, well‐being will also be reduced.