bluuebunny/crossref_metadata_2025 huggingface dataset:
Does water dope carbon nanotubes?
Authors: Bell Robert A. , Payne Michael C. , Mostofi Arash A.
Published: October 2014

We calculate the long-range perturbation to the electronic charge density of carbon nanotubes (CNTs) as a result of the physisorption of a water molecule. We find that the dominant effect is a charge redistribution in the CNT due to polarisation caused by the dipole moment of the water molecule. The charge redistribution is found to occur over a length-scale greater than 30 Å, highlighting the need for large-scale simulations. By comparing our fully first-principles calculations to ones in which the perturbation due to a water molecule is treated using a classical electrostatic model, we estimate that the charge transfer between CNT and water is negligible (no more than 10−4 e per water molecule). We therefore conclude that water does not significantly dope CNTs, a conclusion that is consistent with the poor alignment of the relevant energy levels of the water molecule and CNT. Previous calculations that suggest water n-dopes CNTs are likely due to the misinterpretation of Mulliken charge partitioning in small supercells.
Rotating and thermocapillary-buoyancy-driven flow in a cylindrical enclosure with a partly free surface
Authors: Wu Chun-Mei , Li You-Rong , Liao Rui-Jin
Published: October 2014

In order to understand the characteristics of the complex flow driven by the combined thermocapillary-buoyancy effect and differential rotation of a cylindrical pool and a disk on the free surface, a series of unsteady three-dimensional numerical simulations were performed. Results indicate that the flow is axisymmetric and steady at a small temperature difference and low rotation rates. The basic meridional flow structures are composed of toroidal circulations. With an increase of the rotation rate and/or temperature difference, the basic flow transits to a three-dimensional oscillatory flow. Without rotation, the unstable thermocapillary-buoyancy flow is characterized by pulsating spoke patterns with the periodic growth and decay of temperature and velocity oscillations. When the disk and/or cylinder rotate, the oscillatory flow behaves as temperature and velocity fluctuation waves traveling in the azimuthal direction. The wave propagation velocity and direction, fluctuation amplitude, and wave number depend on the interaction of the thermocapillary, buoyancy, centrifugal and Coriolis forces. The critical conditions for the flow transition are determined. It is found that the critical thermocapillary Reynolds number initially increases before decreasing with the increase of the disk rotation rate, but the rotation of cylinder always retards the flow instability. In addition, the mechanisms of the flow instabilities are discussed and briefly summarized.
Collision lifetimes of polyatomic molecules at low temperatures: Benzene–benzene vs benzene–rare gas atom collisions
Authors: Cui Jie , Li Zhiying , Krems Roman V.
Published: October 2014

We use classical trajectory calculations to study the effects of the interaction strength and the geometry of rigid polyatomic molecules on the formation of long-lived collision complexes at low collision energies. We first compare the results of the calculations for collisions of benzene molecules with rare gas atoms He, Ne, Ar, Kr, and Xe. The comparison illustrates that the mean lifetimes of the collision complexes increase monotonically with the strength of the atom–molecule interaction. We then compare the results of the atom–benzene calculations with those for benzene–benzene collisions. The comparison illustrates that the mean lifetimes of the benzene–benzene collision complexes are significantly reduced due to non-ergodic effects prohibiting the molecules from sampling the entire configuration space. We find that the thermally averaged lifetimes of the benzene–benzene collisions are much shorter than those for Xe with benzene and similar to those for Ne with benzene.
Extracting turbulent spectral transfer from under-resolved velocity fields
Authors: Ni Rui , Voth Greg A. , Ouellette Nicholas T.
Published: October 2014

The strong nonlinearities in turbulent flows drive the transfer of energy and other quantities between different scales of motion. In three-dimensional (3D) turbulence, this transfer organizes into the classic Richardson–Kolmogorov cascade of energy to small scales; in two-dimensional (2D) turbulence, it leads to an inverse cascade of energy to large scales and a forward cascade of enstrophy to small scales. Directly measuring this spectral transfer is difficult, particularly in experiments. Recently developed filtering techniques allow spectral fluxes to be measured locally, but have been assumed to require finely resolved velocity fields that are typically not available in 3D experiments. Here we show, using experimental data in 2D and the results of a 3D simulation, that poorly resolved velocity fields can still be used to extract information about spectral transfer processes. Our results suggest new useful ways of analyzing data from turbulence experiments with limited spatial resolution.
Influence of insulating coating on aluminum wire explosions
Authors: Li Yang , Sheng Liang , Wu Jian , Li Xingwen , Zhao Jizhen , Zhang Mei , Yuan Yuan , Peng Bodong
Published: October 2014

Single wire explosions are widely used in understanding the early stages of z-pinch experiments. This paper presents a serial of experiments conducted on the pulse power generator with ∼1 kA peak current and ∼10 ns rising time in Xi'an Jiao Tong University. Polyimide coated aluminum wires and uncoated ones were tested under three different voltages to analyze the effect of insulating coating. Experimental results showed that insulating coating can increase the energy deposition 10%∼30% in aluminum wires by delaying the voltage collapse and raising the maximum load resistance. The substantial energy deposition resulted in about 20% faster expansion rates for coated wires. Experimental evidence that plasma channel shunts the current from the wire core was observed by streak camera and schlieren graphs. This paper also briefly discussed the influence of nonuniform coating on the morphology of wire expansion.
Communication: Dominance of extreme statistics in a prototype many-body Brownian ratchet
Authors: Hohlfeld Evan , Geissler Phillip L.
Published: October 2014

Many forms of cell motility rely on Brownian ratchet mechanisms that involve multiple stochastic processes. We present a computational and theoretical study of the nonequilibrium statistical dynamics of such a many-body ratchet, in the specific form of a growing polymer gel that pushes a diffusing obstacle. We find that oft-neglected correlations among constituent filaments impact steady-state kinetics and significantly deplete the gel's density within molecular distances of its leading edge. These behaviors are captured quantitatively by a self-consistent theory for extreme fluctuations in filaments' spatial distribution.
Analysis on multiple-component synchronization of ultra-fast time-interleaved analog-to-digital conversion systems and its novel parameterized hardware solution
Authors: Huang Wuhuang , Wang Houjun , Tian Shulin , Ye Peng , Zeng Hao , Qiu Duyu
Published: October 2014

Parallelism-based technique of time-interleaved analog-to-digital conversion (TIADC) has become an effective solution for the higher sampling rate acquisition system to acquire non-repetitive waveforms. With the increase of sampling frequency, the indeterminacy of combining sequence of sampled data among multiple components has become a highlighted barrier for the reset operation of high-speed acquisition systems, and this is especially obvious for the ultra-fast TIADC systems. In this paper, we clarify the root of the problem in multiple-component synchronization (MCS) caused by such reset operation. Also we propose a novel and reliable hardware solution to precisely condition each reset signal, including three key circuit design parameters, i.e., the best time interval, required edge uncertainty, and the minimum delay precision. Besides, the designing scheme and debugging procedures are presented in detail in a generalized platform of this system type. Finally, in order to demonstrate the feasibility, parametric materialization and testing verification are gradually accomplished in a 20 Giga Samples Per Second (GSPS) TIADC system composed of four 5 GSPS ADC components. The results show that the proposed method is feasible and effective for ensuring the combined determinacy of multiple groups of sampled data and solving the MCS problem. In comparison with other existing solutions, it adopts some simple logic components more easily and flexibly, and this is significant for the development of congeneric systems or instruments featuring the MCS.
The coefficient of bond thermal expansion measured by extended x-ray absorption fine structure
Authors: Fornasini P. , Grisenti R.
Published: October 2014

The bond thermal expansion is in principle different from the lattice expansion and can be measured by correlation sensitive probes such as extended x-ray absorption fine structure (EXAFS) and diffuse scattering. The temperature dependence of the coefficient αbond(T) of bond thermal expansion has been obtained from EXAFS for CdTe and for Cu. A coefficient αtens(T) of negative expansion due to tension effects has been calculated from the comparison of bond and lattice expansions. Negative lattice expansion is present in temperature intervals where αbond prevails over αtens; this real-space approach is complementary but not equivalent to the Grüneisen theory. The relevance of taking into account the asymmetry of the nearest-neighbours distribution of distances in order to get reliable bond expansion values and the physical meaning of the third cumulant are thoroughly discussed.
(Ca,Na)(Zn,Mn)2As2: A new spin and charge doping decoupled diluted ferromagnetic semiconductor
Authors: Zhao K. , Chen B. J. , Deng Z. , Han W. , Zhao G. Q. , Zhu J. L. , Liu Q. Q. , Wang X. C. , Frandsen B. , Liu L. , Cheung S. , Ning F. L. , Munsie T. J. S. , Medina T. , Luke G. M. , Carlo J. P. , Munevar J. , Zhang G. M. , Uemura Y. J. , Jin C. Q.
Published: October 2014

Here, we report the successful synthesis of a spin- and charge-decoupled diluted magnetic semiconductor (DMS) (Ca,Na)(Zn,Mn)2As2, crystallizing into the hexagonal CaAl2Si2 structure. The compound shows a ferromagnetic transition with a Curie temperature up to 33 K with 10% Na doping, which gives rise to carrier density of np ∼ 1020 cm−3. The new DMS is a soft magnetic material with HC < 400 Oe. The anomalous Hall effect is observed below the ferromagnetic ordering temperature. With increasing Mn doping, ferromagnetic order is accompanied by an interaction between the local spin and mobile charge, giving rise to a minimum in resistivity at low temperatures and localizing the conduction electrons. The system provides an ideal platform for studying the interaction of the local spins and conduction electrons.
Enhancement of fatigue endurance in ferroelectric PZT ceramic by the addition of bismuth layered SBT
Authors: Namsar O. , Pojprapai S. , Watcharapasorn A. , Jiansirisomboon S.
Published: October 2014

Electrical fatigue properties of (1-x)PZT-xSBT ceramics (x = 0–1.0 weight fraction) were characterized. It was found that pure PZT ceramic had severe polarization fatigue. This was mainly attributed to an occurrence of the macroscopic cracks at near-electrode regions. On the contrary, pure SBT ceramic exhibited excellent fatigue resistance, which was attributed primarily to weak domain wall pinning. As small amount of SBT (0.1 ≤ x ≤ 0.3) was added into PZT, a small reduction of remanent polarization after fatigue process was observed. This demonstrated that these ceramics had high stability during the repeated domain switching due to their low oxygen vacancy concentration. Therefore, these results suggested that this new ceramic PZT-SBT system seemed to be an alternative material for replacing pure PZT in ferroelectric memory applications.
X-ray μ-Laue diffraction analysis of Cu through-silicon vias: A two-dimensional and three-dimensional study
Authors: Sanchez Dario Ferreira , Laloum David , Weleguela Monica Larissa Djomeni , Ulrich Olivier , Audoit Guillaume , Grenier Adeline , Micha Jean-Sébastien , Robach Odile , Lorut Frédéric , Gergaud Patrice , Bleuet Pierre
Published: October 2014

Here, white X-ray μ-beam Laue diffraction is developed and applied to investigate elastic strain distributions in three-dimensional (3D) materials, more specifically, for the study of strain in Cu 10 μm diameter–80 μm deep through-silicon vias (TSVs). Two different approaches have been applied: (i) two-dimensional μ-Laue scanning and (ii) μ-beam Laue tomography. 2D μ-Laue scans provided the maps of the deviatoric strain tensor integrated along the via length over an array of TSVs in a 100 μm thick sample prepared by Focused Ion Beam. The μ-beam Laue tomography analysis enabled to obtain the 3D grain and elemental distribution of both Cu and Si. The position, size (about 3 μm), shape, and orientation of Cu grains were obtained. Radial profiles of the equivalent deviatoric strain around the TSVs have been derived through both approaches. The results from both methods are compared and discussed.
Determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer quantum dots via spectral analysis of optical signature of the Aharanov-Bohm excitons
Authors: Ji Haojie , Dhomkar Siddharth , Roy Bidisha , Shuvayev Vladimir , Deligiannakis Vasilios , Tamargo Maria C. , Ludwig Jonathan , Smirnov Dmitry , Wang Alice , Kuskovsky Igor L.
Published: October 2014

For submonolayer quantum dot (QD) based photonic devices, size and density of QDs are critical parameters, the probing of which requires indirect methods. We report the determination of lateral size distribution of type-II ZnTe/ZnSe stacked submonolayer QDs, based on spectral analysis of the optical signature of Aharanov-Bohm (AB) excitons, complemented by photoluminescence studies, secondary-ion mass spectroscopy, and numerical calculations. Numerical calculations are employed to determine the AB transition magnetic field as a function of the type-II QD radius. The study of four samples grown with different tellurium fluxes shows that the lateral size of QDs increases by just 50%, even though tellurium concentration increases 25-fold. Detailed spectral analysis of the emission of the AB exciton shows that the QD radii take on only certain values due to vertical correlation and the stacked nature of the QDs.
Determination of photocarrier density under continuous photoirradiation using spectroscopic techniques as applied to polymer: Fullerene blend films
Authors: Kanemoto Katsuichi , Nakatani Hitomi , Domoto Shinya
Published: October 2014

We propose a method to determine the density of photocarrier under continuous photoirradiation in conjugated polymers using spectroscopic signals obtained by photoinduced absorption (PIA) measurements. The bleaching signals in the PIA measurements of polymer films and the steady-state absorption signals of oxidized polymer solution are employed to determine the photocarrier density. The method is applied to photocarriers of poly (3-hexylthiophene) (P3HT) in a blended film consisting of P3HT and [6,6]-phenyl C61 butyric acid methyl ester (PCBM). The photocarrier density under continuous photoirradiation of 580 mW/cm2 is determined to be 3.5 × 1016 cm−3. Using a trend of the carrier density increasing in proportion to the square root of photo-excitation intensity, we provide a general formula to estimate the photocarrier density under simulated 1 sun solar irradiation for the P3HT: PCBM film of an arbitrary thickness. We emphasize that the method proposed in this study enables an estimate of carrier density without measuring a current and can be applied to films with no electrodes as well as to devices.
Effect of MgO/Co interface and Co/MgO interface on the spin dependent transport in perpendicular Co/Pt multilayers
Authors: Zhang J. Y. , Yang G. , Wang S. G. , Liu Y. W. , Zhao Z. D. , Wu Z. L. , Zhang S. L. , Chen X. , Feng C. , Yu G. H.
Published: October 2014

Effect of the metal/oxide interface on spin-dependent transport properties in perpendicular [Co/Pt]3 multilayers was investigated. The saturation Hall resistivity (ρxy) is significantly increased by 45% with 1.4 nm thick CoO layer inserted at the top Co/MgO interface; whereas it is increased only 25% with 1 nm thick CoO layer at the bottom MgO/Co interface. The interfacial structures characterized by X-ray photoelectron spectroscopy show that the MgO/Co interface and Co/MgO interface including chemical states play a dominant role on spin-dependent transport, leading to different anomalous Hall behavior.
Mobility characterization of Ge-on-insulator metal-oxide-semiconductor field-effect transistors with striped Ge channels fabricated by lateral liquid-phase epitaxy
Authors: Hosoi Takuji , Suzuki Yuichiro , Shimura Takayoshi , Watanabe Heiji
Published: October 2014

High-mobility metal-oxide-semiconductor field-effect transistors (MOSFETs) consisting of stripe-shaped local germanium-on-insulator (GOI) structures were fabricated by lateral liquid-phase epitaxy (LLPE). The effective hole mobility of back-gate LLPE-grown GOI MOSFETs was accurately and reliably evaluated with a split capacitance-voltage (C-V) method. The superior effective hole mobility of the GOI devices throughout a wide range of accumulated carrier densities over that for a reference silicon-on-insulator device was demonstrated. A very high peak hole mobility of 511 cm2/Vs and an on/off current ratio of 106, together with phonon scattering limited carrier mobility at high temperatures, indicated not only the excellent crystalline quality of LLPE-grown GOI but also surprisingly good interface quality between Ge and the buried oxide.
Stress-induced piezoelectric field in GaN-based 450-nm light-emitting diodes
Authors: Tawfik Wael Z. , Hyeon Gil Yong , Lee June Key
Published: October 2014

We investigated the influence of the built-in piezoelectric field induced by compressive stress on the characteristics of GaN-based 450-nm light-emitting diodes (LEDs) prepared on sapphire substrates of different thicknesses. As the sapphire substrate thickness was reduced, the compressive stress in the GaN layer was released, resulting in wafer bowing. The wafer bowing-induced mechanical stress altered the piezoelectric field, which in turn reduced the quantum confined Stark effect in the InGaN/GaN active region of the LED. The flat-band voltage was estimated by measuring the applied bias voltage that induced a 180° phase shift in the electro-reflectance (ER) spectrum. The piezoelectric field estimated by the ER spectra changed by ∼110 kV/cm. The electroluminescence spectral peak wavelength was blue-shifted, and the internal quantum efficiency was improved by about 22% at a high injection current of 100 mA. The LED on the 60-μm-thick sapphire substrate exhibited the highest light output power of ∼59 mW at an injection current of 100 mA, with the operating voltage unchanged.
Real time characterization of polymer surface modifications by an atmospheric-pressure plasma jet: Electrically coupled versus remote mode
Authors: Knoll A. J. , Luan P. , Bartis E. A. J. , Hart C. , Raitses Y. , Oehrlein G. S.
Published: October 2014

We characterize and distinguish two regimes of atmospheric pressure plasma (APP) polymer interactions depending on whether the electrical interaction of the plasma plume with the surface is significant (coupled) or not (remote). When the plasma is coupled to the surface, localized energy deposition by charged species in filaments dominates the interactions with the surface and produces contained damaged areas with high etch rates that decrease rapidly with plasma source-to-sample distance. For remote APP surface treatments, when only reactive neutral species interact with the surface, we established specific surface-chemical changes and very slow etching of polymer films. Remote treatments appear uniform with etch rates that are highly sensitive to feed gas chemistry and APP source temperature.
A point-like source of extreme ultraviolet radiation based on a discharge in a non-uniform gas flow, sustained by powerful gyrotron radiation of terahertz frequency band
Authors: Glyavin M. Yu. , Golubev S. V. , Izotov I. V. , Litvak A. G. , Luchinin A. G. , Razin S. V. , Sidorov A. V. , Skalyga V. A. , Vodopyanov A. V.
Published: October 2014

The possibility and prospects of extreme ultraviolet (UV) point-like source development are discussed in the present paper. The UV source is based on the discharge sustained by powerful gyrotron radiation of terahertz (THz) frequency band in non-uniform gas flow injected into vacuum volume through a nozzle with diameter less than 1 mm. Recent developments of THz-band gyrotrons with appropriate power level made such discharges possible. First experimental results on a point-like plasma creation by 100 kW radiation of 0.67 THz gyrotron are presented. The possibility of discharge localization within the area less than 1 mm is demonstrated. The discharge emission within the wavelength range from 112 nm to 650 nm was studied. The measured power of light emission in the range of 112–180 nm was measured to be up to 10 kW.
In situ effects of human disturbances on coral reef-fish assemblage structure: temporary and persisting changes are reflected as a result of intensive tourism
Authors: Albuquerque Tiago , Loiola Miguel , Nunes José de Anchieta C. C. , Reis-Filho José Amorim , Sampaio Cláudio L. S. , Leduc Antoine O. H. C.
Published: October 2014

Non-lethal human disturbances are often drivers of change in animal population and community structure. To gauge their severity, short-term behaviour (e.g. avoidance and habituation) has been argued to be a sensitive measure. However, many of these behavioural changes may occur only if disturbance-free habitat is readily accessible. In coral-reef fish, we tested whether human disturbances from intensive (i.e. loud music, swimming, snorkelling, splashing and fish feeding by numerous visitors) tourist visitations resulted in assemblage structure shifts led by short-term behaviour. We monitored fish assemblage before, during and after tourist visitations to monitor changes associated with behaviour. Additionally, we monitored two adjacent reefs not visited by tourists because of difficult approach by boat. We posited that if short-term benefits of relocating to disturbance-free habitat outweigh the costs of tolerating disturbances, fish assemblage structure should shift along with tourist visitation levels. By contrast, if sensitive species are unable or unwilling to relocate, we predicted greater levels of assemblage heterogeneity between the visited and control reefs. Our results showed that in situ human visitations led to significant shifts in assemblage structure, resulting from short-term behavioural changes. Additionally, we showed significant between-reefs differences, whereby control reefs were characterised by higher species richness, larger fish sizes and variations in relative trophic guild prevalence. Our results suggest that short-term relocations to adjacent disturbance-free reefs may not mitigate the effects of human disturbances.
Changing patterns of basic household consumption in the Inner Mongolian grasslands: a case study of policy-oriented adoptive changes in the use of grasslands
Authors: Du B. , Zhen L. , de Groot R. , Goulden C. E. , Long X. , Cao X. , Wu R. , Sun C.
Published: October 2014

Grassland ecosystems, as the basic natural resources in the Inner Mongolia Autonomous Region, are becoming increasingly sensitive to human intervention, leading to deterioration in fragile ecosystems. The goal of this study was to describe the restoration policy-oriented adoptive changes to basic household consumption patterns of food, fuel, and water, and their spatial distribution by grassland types in the region. Basic household consumption data were collected in the meadow steppe (Hulun Buir), typical steppe (Xilin Gol), and semi-desert steppe (Ordos) ecosystems using structured questionnaires administered to 209 herders and farmers. In 2010, the householders’ intake comprised a low amount of agri-crops, including staple foods, vegetables and fruit with a high amount of meat, which still dominated the patterns of food consumption. However, the number of households preferring this pattern is decreasing and higher amounts of agri-crop and lower amounts of meat consumption pattern is increasing. From 1995 to 2010, fuel consumption patterns changed from being dominated by bio-fuels (dung) to being dominated mainly by electricity and gas. However, bio-fuel remains a major energy source for daily life in the meadow steppe ecosystem. In all three surveyed grassland types, the use of coal, electricity and gas increased from 1995 to 2010. The source of domestic water in all three surveyed areas is from groundwater, with an increasing trend to use tap water from a public supply rather than from privately owned wells.
Intracranial microcapsule chemotherapy delivery for the localized treatment of rodent metastatic breast adenocarcinoma in the brain
Authors: Upadhyay Urvashi M. , Tyler Betty , Patta Yoda , Wicks Robert , Spencer Kevin , Scott Alexander , Masi Byron , Hwang Lee , Grossman Rachel , Cima Michael , Brem Henry , Langer Robert
Published: October 2014

Significance

Brain metastases represent the most common intracranial tumors in adults. Adequate chemotherapy delivery to the CNS is hindered by the blood–brain barrier. Efforts in intracranial chemotherapy delivery aim to maximize CNS levels while minimizing systemic toxicity; however, the success has been limited thus far. In this work, intracranial implanted doxorubicin and temozolomide microcapsules are compared with systemic administration in a novel rodent model of breast adenocarcinoma brain metastases. These microcapsules are versatile and efficacious, but that efficacy may depend on the ability of the chemotherapy to diffuse in brain tissue. These insights apply to other non-CNS applications of local drug delivery, and drugs should be evaluated based on their ability to penetrate the targeted tissue as well as their inherent efficacy.
Development of covalent inhibitors that can overcome resistance to first-generation FGFR kinase inhibitors
Authors: Tan Li , Wang Jun , Tanizaki Junko , Huang Zhifeng , Aref Amir R. , Rusan Maria , Zhu Su-Jie , Zhang Yiyun , Ercan Dalia , Liao Rachel G. , Capelletti Marzia , Zhou Wenjun , Hur Wooyoung , Kim NamDoo , Sim Taebo , Gaudet Suzanne , Barbie David A. , Yeh Jing-Ruey Joanna , Yun Cai-Hong , Hammerman Peter S. , Mohammadi Moosa , Jänne Pasi A. , Gray Nathanael S.
Published: October 2014

Significance

Inhibitors of the FGF receptors (FGFRs) are currently under clinical investigation for the treatment of various cancers. All currently approved kinase inhibitors eventually are rendered useless by the emergence of drug-resistant tumors. We used structure-based drug design to develop the first, to our knowledge, selective, next-generation covalent FGFR inhibitors that can overcome the most common form of kinase inhibitor resistance, the mutation of the so-called “gatekeeper” residue located in the ATP-binding pocket. We also describe a novel kinase inhibitor design strategy that uses a single electrophile to target covalently cysteines that are located in different positions within the ATP-binding pocket. These results have important implications for the design of covalent FGFR inhibitors that can overcome clinical resistance.
DICER1/
Alu
RNA dysmetabolism induces Caspase-8–mediated cell death in age-related macular degeneration
Authors: Kim Younghee , Tarallo Valeria , Kerur Nagaraj , Yasuma Tetsuhiro , Gelfand Bradley D. , Bastos-Carvalho Ana , Hirano Yoshio , Yasuma Reo , Mizutani Takeshi , Fowler Benjamin J. , Li Shengjian , Kaneko Hiroki , Bogdanovich Sasha , Ambati Balamurali K. , Hinton David R. , Hauswirth William W. , Hakem Razqallah , Wright Charles , Ambati Jayakrishna
Published: October 2014

Significance

Geographic atrophy is a late stage of age-related macular degeneration (AMD) that causes blindness in millions worldwide characterized by death of the retinal pigmented epithelium (RPE). We previously reported that RPE death is due to a deficiency in the enzyme DICER1, which leads to accumulation of toxic
Alu
RNA. We also demonstrated that
Alu
RNA causes RPE death by activating an immune platform called the NLRP3 inflammasome. However, the precise mechanisms of RPE death in this disease remained unresolved. The present study indicates that
Alu
RNA induces RPE death by activating the enzyme Caspase-8 downstream of inflammasome activation and that blocking Caspase-8 rescues RPE degeneration. This implicates apoptosis as the cell death pathway responsible for
Alu
RNA cytotoxicity, and these findings provide new potential therapeutic targets for this disease.
Vegetation dynamics and rainfall sensitivity of the Amazon
Authors: Hilker Thomas , Lyapustin Alexei I. , Tucker Compton J. , Hall Forrest G. , Myneni Ranga B. , Wang Yujie , Bi Jian , Mendes de Moura Yhasmin , Sellers Piers J.
Published: October 2014

Significance

Understanding the sensitivity of tropical vegetation to changes in precipitation is of key importance for assessing the fate of the Amazon rainforest and predicting atmospheric CO2levels. Using improved satellite observations, we reconcile observational and modeling studies by showing that tropical vegetation is highly sensitive to changes in precipitation and El Niño events. Our results show that, since the year 2000, the Amazon forest has declined across an area of 5.4 million km2as a result of well-described reductions in rainfall. We conclude that, if drying continues across Amazonia, which is predicted by several global climate models, this drying may accelerate global climate change through associated feedbacks in carbon and hydrological cycles.
Distinct macrophage lineages contribute to disparate patterns of cardiac recovery and remodeling in the neonatal and adult heart
Authors: Lavine Kory J. , Epelman Slava , Uchida Keita , Weber Kassandra J. , Nichols Colin G. , Schilling Joel D. , Ornitz David M. , Randolph Gwendalyn J. , Mann Douglas L.
Published: October 2014

Significance

This study addresses a fundamentally important and widely debated issue in the field of inflammation, which is why inflammation can be simultaneously deleterious after injury and yet is essential for tissue repair. Recently, an important new paradigm has emerged in the macrophage field: Organs are replete with resident macrophages of embryonic origin, distinct from monocyte-derived macrophages. In this article, we use a new model of cardiac injury and show that distinct macrophage populations derived from embryonic and adult lineages are important determinants of tissue repair and inflammation, respectively. Our data suggest that therapeutics, which inhibit monocyte-derived macrophages and/or selectively harness the function of embryonic-derived macrophages, may serve as novel treatments for heart failure.
Wild chimpanzees plan their breakfast time, type, and location
Authors: Janmaat Karline R. L. , Polansky Leo , Ban Simone Dagui , Boesch Christophe
Published: October 2014

Significance

How do large-brained primates maintain high rates of energy intake when times are lean? By analyzing early-morning departure times and sleeping nest positioning of female chimpanzees as a function of the ephemerality of next day’s breakfast fruit and its location, we found evidence that wild chimpanzees flexibly plan when and where they will have breakfast after weighing multiple factors, such as the time of day, their egocentric distance to, and the type of food to be eaten. To our knowledge, our findings reveal the first clear example of a future-oriented cognitive mechanism by which hominoids, like great apes, can buffer the effect of seasonal declines in food availability and increased interspecific competition to facilitate first access to nutritious food.
Dynamic population mapping using mobile phone data
Authors: Deville Pierre , Linard Catherine , Martin Samuel , Gilbert Marius , Stevens Forrest R. , Gaughan Andrea E. , Blondel Vincent D. , Tatem Andrew J.
Published: October 2014

Significance

Knowing where people are is critical for accurate impact assessments and intervention planning, particularly those focused on population health, food security, climate change, conflicts, and natural disasters. This study demonstrates how data collected by mobile phone network operators can cost-effectively provide accurate and detailed maps of population distribution over national scales and any time period while guaranteeing phone users’ privacy. The methods outlined may be applied to estimate human population densities in low-income countries where data on population distributions may be scarce, outdated, and unreliable, or to estimate temporal variations in population density. The work highlights how facilitating access to anonymized mobile phone data might enable fast and cheap production of population maps in emergency and data-scarce situations.
Defense mutualisms enhance plant diversification
Authors: Weber Marjorie G. , Agrawal Anurag A.
Published: October 2014

Significance

Plants that provide food and housing to animals in return for defense against enemies are classic examples of mutualistic partnerships in nature. Here, we show that the evolution of such plant–animal mutualisms also can lead to a trajectory of accelerated accumulation of plant species in the lineages that participate in these cooperative interactions. We found that the evolution of plant organs (extrafloral nectaries) that facilitate mutualisms with animal defenders was repeatedly followed by increased rates of diversification across distantly related plant lineages. These results suggest that by enabling ecological interactions with animals, the convergent evolution of relatively simple glands changed the course of plant evolution toward greater protection from pests and accelerated the generation of biodiversity.
Aag-initiated base excision repair promotes ischemia reperfusion injury in liver, brain, and kidney
Authors: Ebrahimkhani Mohammad R. , Daneshmand Ali , Mazumder Aprotim , Allocca Mariacarmela , Calvo Jennifer A. , Abolhassani Nona , Jhun Iny , Muthupalani Sureshkumar , Ayata Cenk , Samson Leona D.
Published: October 2014

Significance

Ischemia reperfusion (I/R)-induced tissue injury and inflammation encompasses a wide range of human disease, including stroke, hepatic and renal failure, and myocardial infarction. Generation of highly reactive oxygen and nitrogen species during I/R results in DNA damage that is subject to numerous DNA repair processes. Base excision repair (BER) initiated by various DNA glycosylases is critical for the repair of reactive oxygen and nitrogen species (RONS)-induced DNA damage. Our data describe a new paradigm wherein the Aag BER DNA glycosylase enzyme promotes, rather than prevents, tissue injury and inflammation in liver, brain, and kidney following I/R. This finding reveals a detrimental facet of DNA repair during inflammation and presents a novel target for controlling I/R-induced injury.
Developing functional musculoskeletal tissues through hypoxia and lysyl oxidase-induced collagen cross-linking
Authors: Makris Eleftherios A. , Responte Donald J. , Paschos Nikolaos K. , Hu Jerry C. , Athanasiou Kyriacos A.
Published: October 2014

Significance

The inadequate mechanical properties of engineered tissues have prevented related therapies from clinical translation. Collagen cross-links correlate with the mechanical integrity of tissues; however, addressing the weakness of neotissues through enhancing collagen cross-links has not received the attention it deserves. The present study demonstrates, both in vitro and in vivo, that improvements in the mechanical properties of native and engineered tissues can be attained using endogenous (hypoxia-mediated) lysyl oxidase and exogenous application of lysyl oxidase-like 2, which are enzymes responsible for collagen cross-linking. By promoting an ∼16-fold increase in collagen cross-linking and, concomitantly, an approximately fivefold enhancement in the neotissue’s mechanical properties, this work creates new prospects for regenerative medicine. The methods developed here work across a spectrum of collagen-rich tissues and are clinically applicable.
Mating-type switching by chromosomal inversion in methylotrophic yeasts suggests an origin for the three-locusSaccharomyces cerevisiaesystem
Authors: Hanson Sara J. , Byrne Kevin P. , Wolfe Kenneth H.
Published: October 2014

Significance

Saccharomyces cerevisiaeundergoes a programmed DNA rearrangement to switch between mating types a and alpha. The origins of this complex and multifaceted process, which requires three copies of the mating-type (MAT) locus (with two silenced), have remained unknown. In this study we present a mechanism for mating-type switching in methylotrophic yeasts that shares a common origin with the well-characterized system inS.cerevisiaebut has simpler components. This system requires only two copies of theMATlocus, with one copy transcriptionally repressed by proximity to centromeric or telomeric chromatin. Switching between the mating types occurs by recombination between inverted-repeat sequences flanking theMATloci. This system suggests an ancestral mechanism for mating-type switching in yeasts.
Multiple patterns of polymer gels in microspheres due to the interplay among phase separation, wetting, and gelation
Authors: Yanagisawa Miho , Nigorikawa Shinpei , Sakaue Takahiro , Fujiwara Kei , Tokita Masayuki
Published: October 2014

Significance

We investigate how microdroplet confinement affects pattern formation of a polymer blend in the liquid-and-gel coexisting phase, wherein interactions between the droplet surface and the polymers regulate wettability of the gelation polymer. The complete and partial wetting of the polymers produces two stable states: hollow microspheres and hemisphere microgels. In addition, gelation during phase separation produces various shapes as trapped states. The relation between capsule thickness and droplet size is changed by the dynamical coupling. Furthermore, multiple patterns with spherical asymmetric shapes are produced by the partial wetting and shape deformation along the phase boundaries between the sol/gel phases. These findings reveal a complex pattern formation arising from the interplay among the interfacial tensions, gel elasticity, and wetting in microspheres.
Replication initiator DnaA binds at the
Caulobacter
centromere and enables chromosome segregation
Authors: Mera Paola E. , Kalogeraki Virginia S. , Shapiro Lucy
Published: October 2014

Significance

DnaA is an essential and conserved bacterial protein that enables the initiation of DNA replication. Although it is commonly held that the onset of bacterial chromosome segregation depends on the initiation of DNA replication, we have found that in
Caulobacter crescentus
, chromosome segregation can be induced in a DnaA-dependent, yet replication-independent manner. The chromosome replication origin, containing essential DnaA binding motifs, resides 8 kb from the centromere
parS
region that also contains DnaA binding motifs. The centromere
parS
region bound to the ParB partition protein initiates movement across the cell followed by the origin region. Mutations in a centromere DnaA motif that alter DnaA–centromere interaction exhibit aberrant patterns of ParB/
parS
translocation, implicating DnaA in the process of chromosome segregation.
Exploring “happiness” and “pain” across languages and cultures
Authors: Goddard Cliff , Ye Zhengdao
Published: October 2014

This paper argues that the cross-linguistic study of subjective experience as expressed, described and construed in language cannot be set on a sound footing without the aid of a systematic and non-Anglocentric approach to lexical semantic analysis. This conclusion follows from two facts, one theoretical and one empirical. The first is the crucial role of language in accessing and communicating about feelings. The second is the demonstrated existence of substantial, culture-related differences between the meanings of emotional expressions in the languages of the world. We contend that the NSM approach to semantic and cultural analysis (Wierzbicka 1996; Gladkova 2010; Levisen 2012; Goddard 2011; Goddard and Wierzbicka 2014a; Wong 2014; among other works) provides the necessary conceptual and analytical framework to come to grips with these facts. This is demonstrated in practice by the studies of “happiness-like” and “pain-like” expressions across eight languages, undertaken in the present volume. At the same time as probing the precise meanings of these expressions, the authors provide extensive cultural contextualization, showing in some detail how the meanings they are analyzing are truly “cultural meanings”. The project exemplified by the volume can also be read as a linguistically-anchored contribution to cultural psychology (Shweder 2004, 2003), the quest to understand and appreciate the mental life of others in a full spirit of psychological pluralism.
“Pain” and “suffering” in cross-linguistic perspective
Authors: Wierzbicka Anna
Published: October 2014

This paper builds on findings of the author’s 1999 bookEmotions Across Languages and Cultures: Diversity and Universals, which tentatively identified eleven universals pertaining to human emotions. The paper probes some of those “emotional universals” further, especially in relation to ‘laughing’, ‘crying’, and ‘pain’. At the same time, the author continues her campaign against pseudo-universals, focussing in particular on the anthropological and philosophical discourse of “suffering”. The paper argues for the Christian origins of the concept of “suffering” lexically embodied in European languages, and contrasts it with the Buddhist concept of ‘dukkha’, usually rendered in Anglophone discussions of Buddhism with the wordsuffering.
The meaning of “happiness” (xìngfú) and “emotional pain” (tòngkŭ) in Chinese
Authors: Ye Zhengdao
Published: October 2014

This paper undertakes detailed meaning analyses ofxìngfú, a concept central to contemporary Chinese discourse on “happiness,” and its oppositetòngkŭ(‘emotional anguish/suffering/pain’). Drawing data from five Chinese corpora and applying the semantic techniques developed by Natural Semantic Metalanguage (NSM) researchers, the present study reveals a conceptualization of happiness that is markedly different from that encoded in the English concept ofhappiness. Particularly, the analysis shows that the Chinese conception ofxìngfúis relational in nature, being firmly anchored in interpersonal relationships. Loosely translatable as ‘a belief that one is loved and cared for’,xìngfúreflects the Chinese idea of love, which places emphasis on actions over words and is intrinsically related to other core cultural values, such asxiào(‘filial piety’). The paper relates semantic discussion directly to recent research on happiness and subjective well-being involving Chinese subjects, highlighting and problematizing the role of language in the emergent and fast-growing field of happiness research and stressing the important role of culture in global “happiness research”.
The semantics and morphosyntax of tare “hurt/pain” in Koromu (PNG)
Authors: Priestley Carol
Published: October 2014

This paper examines the words and constructions that Koromu speakers (PNG) use to talk about tare ‘hurt/pain’ and other painful sensations. It also reflects on links to cultural and environmental influences in daily life and key life events, environmental knowledge and traditional health care. Terms such as warike ‘be/feel bad’, tare ‘hurt/pain’, perere ‘hurt: sting, cut, burn’, and kaho ‘ache: burn, pierce’ are used in different constructions with varying emphases. These constructions are among the most typologically interesting in Koromu grammar. They are related to, but also distinct from, constructions found in other Papuan languages. They include experiencer object constructions, serial verb constructions with the grammaticized valency-increasing verb here/he put, and nominal constructions with, or without, prominent noun-phrase marking.
The linguistic representation of gender violence in (written) media discourse
Authors: Santaemilia José , Maruenda Sergio
Published: October 2014

‘Woman’ is a key social actor, and a central conceptualization, in the construction of media discourses of gender-based violence. Scholarly research at the turn of the 21st century (Bengoechea 2000; Lledó 2002; Fernández Díaz 2003; Jorge 2004) showed that in the Spanish press, media discourses had a tendency to naturalize male aggression not as violence but as part of the (private) sexual arrangement between the sexes. In this paper we explore the treatment of the phrasemujer maltratada(EN ‘battered woman’) in intimate partner violence newspaper articles from 2005 to 2010. Our aims are: (i) to account for the discursive representation of violence against women (VAW) in Spanish contemporary media discourse in recent years; and (ii) to unveil the expectations about gender, sexuality and power implicit in public discourses about VAW, given their apparent objectivity. In doing so, we draw on the evaluation framework for the analysis of news reports proposed by White (2004, 2006) and on Corpus Linguistics tools.
The write stuff
Authors: Freyberg Robin , Chung Cindy K. , Freyberg Zachary , Barnhill John , Ferrando Stephen , Pennebaker James W.
Published: October 2014

Clinicians often wonder if the single sentence from the Folstein Mini-Mental Status Exam (MMSE) offers meaningful information about the patient. We compared single sentences derived from the MMSE generated by 3 groups of participants — hospitalized medically-ill patients with psychiatric comorbidity, hospitalized medically-ill patients without psychiatric comorbidity, and non-hospitalized non-psychiatric participants. These sentences were analyzed for themes using manual thematic coding and a semi-automatic computerized method, the Meaning Extraction Method (MEM). We found that thematic content obtained from as little as a single sentence could differentiate between participant groups using both methods. Specifically, psychiatric patients used more power themes, focused on states other than the present, and were less interpersonally engaged than the other groups. Thematic content also indicated cognitive status through scores on the Clock Drawing Test (CDT) and MMSE. Our findings suggest that a single sentence can provide meaningful information about patients with medical and psychiatric comorbidity.
Narative journalism in the contemporary newsroom
Authors: Shim Hoon
Published: October 2014

This study examines the journalistic discourse in American trade publications toward a storytelling format, competitive in contemporary daily papers, which has long been considered as not appropriate for objective news writing. Thomas Kuhn’s concept of ‘paradigm’ was employed in examining and analyzing narrative discourse in trade journals. The outcome of text-analysis revealed that assenters in narrative news writing outnumbered the dissenters; narrative upholders have vividly attempted to construct a friendly perspective toward a storytelling format by eulogizing the prose style, battering the old form of news production, and distancing the previous literary movement from contemporary narrative news writing. The author concludes that the change of journalistic perception toward the narrative style documents the hierarchical relationship between the occupational ideology and the market ideology within which the journalistic paradigm of news writing can be modified and replaced when the established one — the inverted pyramid news writing — fails to satisfy the concerns of the media industry.