bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of disorder on the magnetic properties of cubic Mn2RuxGa compounds: A first-principles study
Authors: Galanakis I. , Özdoğan K. , Şaşıoğlu E. , Blügel S.
Published: July 2014

We perform first-principles electronic structure calculations to explain the anomalous magnetic behavior of the Mn2RuxGa compounds upon Ru doping as shown experimentally recently by Kurt et al. [Phys. Rev. Lett. 112, 027201 (2014)]. Our results suggest that disorder caused by the distribution of the Mn and Ru atoms at various sites reproduces the experimental data. All compounds present antiparallel alignment of the neighboring Mn magnetic moments and, with the exception of Mn2RuGa, none of them presents half metallic behavior.
Examining the temporal evolution of hypervelocity impact phenomena via high-speed imaging and ultraviolet-visible emission spectroscopy
Authors: Tandy J. D. , Mihaly J. M. , Adams M. A. , Rosakis A. J.
Published: July 2014

The temporal evolution of a previously observed hypervelocity impact-induced vapor cloud [Mihaly et al., Int. J. Impact Eng. 62, 13 (2013)] was measured by simultaneously recording several full-field, near-IR images of the resulting emission using an OMA-V high-speed camera. A two-stage light-gas gun was used to accelerate 5 mg Nylon 6/6 right-cylinders to speeds between 5 km/s and 7 km/s to impact 1.5 mm thick 6061-T6 aluminum target plates. Complementary laser-side-lighting [Mihaly et al., Int. J. Impact Eng. 62, 13 (2013); Proc. Eng. 58, 363 (2013)] and front-of-target (without laser illumination) images were also captured using a Cordin ultra-high-speed camera. The rapid expansion of the vapor cloud was observed to contain a bright, emitting exterior, and a darker, optically thick interior. The shape of this phenomenon was also observed to vary considerably between experiments due to extremely high-rate (>250 000 rpm) of tumbling of the cylindrical projectiles. Additionally, UV-vis emission spectra were simultaneously recorded to investigate the temporal evolution of the atomic and molecular composition of the up-range, impact-induced vapor plume. A PI-MAX3 high-speed camera coupled to an Acton spectrograph was utilized to capture the UV-vis spectra, which shows an overall peak in emission intensity between approximately 6–10 μs after impact trigger, corresponding to an increased quantity of emitting vapor/plasma passing through the spectrometer slit during this time period. The relative intensity of the numerous spectral bands was also observed to vary according to the exposure delay of the camera, indicating that the different atomic/molecular species exhibit a varied temporal evolution during the vapor cloud expansion. Higher resolution spectra yielded additional emission lines/bands that provide further evidence of interaction between fragmented projectile material and the 1 mmHg atmosphere inside the target chamber. A comparison of the data to down-range emission spectra also revealed differences in the relative intensities of the atomic/molecular composition of the observed vapor clouds.
Shockless compression and release behavior of beryllium to 110 GPa
Authors: Brown J. L. , Knudson M. D. , Alexander C. S. , Asay J. R.
Published: July 2014

A magnetohydrodynamic loading technique was used to shocklessly compress beryllium to peak longitudinal stresses of 19–110 GPa and, subsequently, unload in order to determine both the compressive response and also the shear stress supported upon release. Loading strain rates were on the order of 106 s−1, while the unloading rates were nearly constant at 3 × 105 s−1. Velocimetry was used to monitor the ramp and release behavior of a beryllium/lithium fluoride window interface. After applying window corrections to infer in situ beryllium velocities, a Lagrangian analysis was employed to determine the material response. The Lagrangian wavespeed-particle velocity response is integrated to generate the stress-strain path, average change in shear stress over the elastic unloading, and estimates of the shear modulus at peak compression. These data are used to infer the pressure dependence of the flow strength at the unloading rate. Comparisons to several strength models reveal good agreement to 45 GPa, but the data indicate 20%–30% higher strength near 100 GPa.
The effect of Ca-substitution in La-site on the magnetic properties of La2CoMnO6
Authors: Li Qiu-hang , Li Na , Hu Jian-zhong , Han Qi , Ma Qing-shan , Ge Lei , Xiao Biao , Xu Ming-xiang
Published: July 2014

Double perovskite La2-xCaxCoMnO6 (x = 0, 0.1, 0.2, 0.5) ceramics samples were synthesized by the standard solid-state reaction method. The crystal structures have been confirmed to be monoclinic perovskite structure with space group of P21/n at room temperature by the powder x-ray diffraction (Cu-Kα). The grains of the samples are relatively dense and distribute in random directions from the scanning electron microscope patterns. Holes are doped into La2CoMnO6 with the substitution of the Ca2+ ions in La-site, and further lead to the valences of Mn ions and Co ions transforming from Mn4+ and Co2+ to Mn3+ and Co3+, respectively. Ferromagnetic coupling of Mn4+-O2–-Co2+ and antiferromagnetic coupling of Mn3+-O2–-Co3+ are coexistent in La2-xCaxCoMnO6 system, which correspond to two transitions existed in field-cooling magnetization versus temperature curves. Curie temperature of La2-xCaxCoMnO6 system decreases with the increasing of Ca-substitution amount. The coexistence of different magnetic phases leads to the exchange bias effect.
Engineered three-dimensional microfluidic device for interrogating cell-cell interactions in the tumor microenvironment
Authors: Hockemeyer K. , Janetopoulos C. , Terekhov A. , Hofmeister W. , Vilgelm A. , Costa Lino , Wikswo J. P. , Richmond A.
Published: July 2014

Stromal cells in the tumor microenvironment play a key role in the metastatic properties of a tumor. It is recognized that cancer-associated fibroblasts (CAFs) and endothelial cells secrete factors capable of influencing tumor cell migration into the blood or lymphatic vessels. We developed a microfluidic device that can be used to image the interactions between stromal cells and tumor cell spheroids in a three dimensional (3D) microenvironment while enabling external control of interstitial flow at an interface, which supports endothelial cells. The apparatus couples a 200-μm channel with a semicircular well to mimic the interface of a blood vessel with the stroma, and the design allows for visualization of the interactions of interstitial flow, endothelial cells, leukocytes, and fibroblasts with the tumor cells. We observed that normal tissue-associated fibroblasts (NAFs) contribute to the “single file” pattern of migration of tumor cells from the spheroid in the 3D microenvironment. In contrast, CAFs induce a rapid dispersion of tumor cells out of the spheroid with migration into the 3D matrix. Moreover, treatment of tumor spheroid cultures with the chemokine CXCL12 mimics the effect of the CAFs, resulting in similar patterns of dispersal of the tumor cells from the spheroid. Conversely, addition of CXCL12 to co-cultures of NAFs with tumor spheroids did not mimic the effects observed with CAF co-cultures, suggesting that NAFs produce factors that stabilize the tumor spheroids to reduce their migration in response to CXCL12.
Air damping of atomically thin MoS2 nanomechanical resonators
Authors: Lee Jaesung , Wang Zenghui , He Keliang , Shan Jie , Feng Philip X.-L.
Published: July 2014

We report on experimental measurement of air damping effects in high frequency nanomembrane resonators made of atomically thin molybdenum disulfide (MoS2) drumhead structures. Circular MoS2 nanomembranes with thickness of monolayer, few-layer, and multi-layer up to ∼70 nm (∼100 layers) exhibit intriguing pressure dependence of resonance characteristics. In completely covered drumheads, where there is no immediate equilibrium between the drum cavity and environment, resonance frequencies and quality (Q) factors strongly depend on environmental pressure due to bulging of the nanomembranes. In incompletely covered drumheads, strong frequency shifts due to compressing-cavity stiffening occur above ∼200 Torr. The pressure-dependent Q factors are limited by free molecule flow (FMF) damping, and all the mono-, bi-, and tri-layer devices exhibit lower FMF damping than thicker, conventional devices do.
Electric field modulation of ultra-high resonance frequency in obliquely deposited [Pb(Mg1/3Nb2/3)O3]0.68-[PbTiO3]0.32(011)/FeCoZr heterostructure for reconfigurable magnetoelectric microwave devices
Authors: Phuoc Nguyen N. , Ong C. K.
Published: July 2014

The multiferroic heterostructure of FeCoZr/[Pb(Mg1/3Nb2/3)O3]0.68-[PbTiO3]0.32(011) (PMN-PT) prepared by oblique sputtering deposition technique shows a large electrical tunability of ultra-high ferromagnetic resonance frequency from 7.4 GHz to 12.3 GHz. Moreover, we experimentally demonstrate the possibility of realizing electrically reconfigurable magnetoelectric microwave devices with ultra-low power consumption by employing the heterostructure under different resetting electric fields through a reconfiguration process. In particular, the tunability of the FeCoZr/PMN-PT heterostructure from 8.2 GHz to 11.6 GHz can retain in a remanent state after releasing the resetting electric field. This suggests that the tunable microwave devices based on such heterostructures are permanently reconfigurable by simply using a trigger electric field double-pulse which requires much less energy than that of the conventional ones wherein an electric field needs to be constantly applied during operation.
Band alignment between GaN and ZrO2 formed by atomic layer deposition
Authors: Ye Gang , Wang Hong , Arulkumaran Subramaniam , Ng Geok Ing , Li Yang , Liu Zhi Hong , Ang Kian Siong
Published: July 2014

The band alignment between Ga-face GaN and atomic-layer-deposited ZrO2 was investigated using X-ray photoelectron spectroscopy (XPS). The dependence of Ga 3d and Zr 3d core-level positions on the take-off angles indicated upward band bending at GaN surface and potential gradient in ZrO2 layer. Based on angle-resolved XPS measurements combined with numerical calculations, valence band discontinuity ΔEV of 1 ± 0.2 eV and conduction band discontinuity ΔEC of 1.2 ± 0.2 eV at ZrO2/GaN interface were determined by taking GaN surface band bending and potential gradient in ZrO2 layer into account.
Integrated pitch control for wind turbine based on a novel pitch control system
Authors: Yin Xiu-xing , Lin Yong-gang , Li Wei , Gu Ya-jing
Published: July 2014

A novel pitch control system is proposed for wind turbine to smooth output power and load fluctuations. This system is driven by a servo-valve controlled hydraulic motor and is precisely controlled to track the desired pitch angle trajectory. Nonlinear modeling and characteristics of this system are presented and analyzed. An adaptive nonlinear sliding mode pitch angle controller is designed to deal with the uncertainties and external disturbances in this system. An integrated pitch control strategy is proposed to generate the reference pitch commands for this system by considering the load reductions. The proposed system, pitch controller, and the control strategy have been validated for efficient and accurate pitch control performances by comparative experimental results under realistic wind speeds.
Kikuyu-based pasture for dairy production: a review
Authors: García S. C. , Islam M. R. , Clark C. E. F. , Martin P. M.
Published: July 2014

The amount of pasture grown and converted to animal product is closely linked with the profitability of pasture-based systems. Kikuyu (Pennisetum clandestinum Hochst. ex Chiov.) is the predominant C4 grass in coastal Australian beef and dairy systems. These kikuyu-based production systems face several key challenges to achieving high levels of productivity. In this review, we bring together the literature to highlight the opportunities for closing the gap between current and potential utilisation and for increasing dairy production from kikuyu-based pastures. More specifically, we highlight the significant gains that can be made on kikuyu-based commercial farms based on a conceptual model to show where the main losses originate, namely input and grazing management. The physical limitations associated with kikuyu for dairy systems are also presented, such as the relatively higher content of cell wall and lower content of water-soluble carbohydrates, together with nutrient imbalances relative to other grass species. Together, these limitations clearly indicate the need of supplying cows with supplements (particularly grain-based concentrates) to achieve moderate to high milk yield per cow. To achieve this without compromising pasture utilisation, dairy producers farming on kikuyu-based pastures need to use relatively greater stocking rates to generate enough demand of feed that can be used to align rate of pasture intake with rate of pasture growth, creating enough deficit of feed per cow to justify the addition of supplementary feed without impinging on pasture utilisation. The variability that exists between cows in kikuyu dry matter and neutral detergent fibre intake is also highlighted in this review, opening up new avenues of research that may allow significant productivity gains for kikuyu-based dairy farming in the future.
Right sizes of nano- and microstructures for high-performance and rigid bulk thermoelectrics
Authors: Wang Hongchao , Bahk Je-Hyeong , Kang Chanyoung , Hwang Junphil , Kim Kangmin , Kim Jungwon , Burke Peter , Bowers John E. , Gossard Arthur C. , Shakouri Ali , Kim Woochul
Published: July 2014

Significance

PbTe is known to be a promising thermoelectric material for waste heat recovery, so it has been the subject of extensive research involving new approaches. It is important to note that the performances of these developed materials can depend on the material synthesis conditions. We investigated three different routes of synthesizing 2% Na-doped PbTe and found that its thermoelectric figure of merit,
zT
, can be enhanced to ∼2.0 at 773 K. Also, the mechanical hardness of the sample synthesized by this condition was nearly double than that of the other samples. Our study shows that the size of nano- and microstructures can vary significantly by the choice of synthesis methods, which can explain the variation in
zT
s and mechanical hardness.
In vitro evaluation of glyceric acid and its glucosyl derivative, α-glucosylglyceric acid, as cell proliferation inducers and protective solutes
Authors: Sato Shun , Kitamoto Dai , Habe Hiroshi
Published: July 2014

We demonstrate that 0.78 mm glyceric acid activated the proliferation of human dermal fibroblasts by about 45%, whereas 34 mm α-glucosylglyceric acid (GGA) increased collagen synthesis by the fibroblasts by 1.4-fold compared to that in the absence of GGA. The two substances also exerted protective effects on both DNA scission by the hydroxyl radical and protein aggregation by heat in vitro.
Sex differences in ventral side colouration of Alpine newts
Authors: Kopecký Oldřich , Šichtař Jiří
Published: July 2014

Sexual selection based on visual stimuli was recently studied in several amphibian species with permanent or temporary dichromatism. The Alpine newt (Ichthyosaura alpestris) is a Caudate species with prominent sexual dichromatism during the breeding period. We focused on the intersexual differences in the orange, carotenoid-base ventral colouration of this widespread European species. We used an image analysis approach to compare the content of the red colour and saturation of the belly in 80 male and 62 female aquatic adult newts captured during spring migration in two localities in the Czech Republic. Both studied colour parameters of the ventral side of the Alpine newt are connected with sex. Males have significantly higher values of saturation on both localities, but the relationship with red content was not so clear. Individual characteristics (body condition, body length) affect colour variables of males and females similarly. Effect of body condition on colour variables was not demonstrated. Therefore we presume that the pronounced colouration of males is a cue facilitating detection, localisation or interspecies identification, rather than a direct component of male quality as assessed by females.
Eikonal equations in metric spaces
Authors: Giga Yoshikazu , Hamamuki Nao , Nakayasu Atsushi
Published: July 2014

A new notion of a viscosity solution for Eikonal equations in a general metric space is introduced. A comparison principle is established. The existence of a unique solution is shown by constructing a value function of the corresponding optimal control theory. The theory applies to infinite dimensional setting as well as topological networks, surfaces with singularities.
Mennicke symbols, 𝐾-cohomology and a Bass-Kubota theorem
Authors: Fasel J.
Published: July 2014

If

A
A

is a smooth algebra of dimension

d
≥
3

d\geq 3

over a perfect field

k
k

of characteristic different from

2
2

, then we show that the universal Mennicke symbol

M

S

d
+
1

(
A
)

MS_{d+1}(A)

is isomorphic to the

K
K

-cohomology group

H
d

(
A
,

K

d
+
1

)

H^d(A,K_{d+1})

. We then prove an analogue of the Bass-Kubota theorem for smooth affine surfaces over the algebraic closure of a finite field.
Modeling time-dependent transcription effects of HER2 oncogene and discovery of a role for E2F2 in breast cancer cell-matrix adhesion
Authors: Bollig-Fischer Aliccia , Marchetti Luca , Mitrea Cristina , Wu Jiusheng , Kruger Adéle , Manca Vincenzo , Drăghici Sorin
Published: July 2014

Motivation: Oncogenes are known drivers of cancer phenotypes and targets of molecular therapies; however, the complex and diverse signaling mechanisms regulated by oncogenes and potential routes to targeted therapy resistance remain to be fully understood. To this end, we present an approach to infer regulatory mechanisms downstream of the HER2 driver oncogene in SUM-225 metastatic breast cancer cells from dynamic gene expression patterns using a succession of analytical techniques, including a novel MP grammars method to mathematically model putative regulatory interactions among sets of clustered genes.

Results: Our method highlighted regulatory interactions previously identified in the cell line and a novel finding that the HER2 oncogene, as opposed to the proto-oncogene, upregulates expression of the E2F2 transcription factor. By targeted gene knockdown we show the significance of this, demonstrating that cancer cell-matrix adhesion and outgrowth were markedly inhibited when E2F2 levels were reduced. Thus, validating in this context that upregulation of E2F2 represents a key intermediate event in a HER2 oncogene-directed gene expression-based signaling circuit. This work demonstrates how predictive modeling of longitudinal gene expression data combined with multiple systems-level analyses can be used to accurately predict downstream signaling pathways. Here, our integrated method was applied to reveal insights as to how the HER2 oncogene drives a specific cancer cell phenotype, but it is adaptable to investigate other oncogenes and model systems.

Availability and implementation: Accessibility of various tools is listed in methods; the Log-Gain Stoichiometric Stepwise algorithm is accessible at http://www.cbmc.it/software/Software.php .

Contact:  bollig@karmanos.org

Supplementary information:  Supplementary data are available at Bioinformatics online.
Ancient Commentators on Aristotle
Authors: Sellars John
Published: July 2014

In the first century bce, the previously unknown lecture notes that we now know as Aristotle’s works were rediscovered, and from then until the end of antiquity they received close attention from philosophers. Both committed followers of Aristotle and Platonists who held that Aristotle was broadly in agreement with Plato wrote commentaries on his works. For the later Platonists in particular, writing commentaries on Aristotle (as well as Plato) became an established way of doing philosophy. Although some commentaries are lost and others survive only in fragments, a substantial number of often lengthy commentaries survive, filling twenty-three large volumes in the standard collection of the Greek texts. To these we can add the Latin commentaries of Boethius and more recent discoveries both in Greek and in Arabic translation. The commentaries are valuable for a number of reasons: for their interpretations of the fine details of Aristotle’s texts, for the philosophical contributions they make to the topics they discuss, and for the information they preserve about earlier philosophers whose works are otherwise lost.
Margherita Datini
Authors: James Carolyn
Published: July 2014

The 252 extant letters of Margherita Datini (b. 1360–d. 1423) to her husband, the merchant Francesco di Marco Datini (b. c. 1335–d. 1410), represent the largest collection of early Italian vernacular correspondence by a lay woman to have come to light. They are all the more unusual because Francesco’s letters to Margherita also survive, enabling us to follow a marital conversation that continued for almost three decades. The couple’s exchanges reveal a very different portrait of marriage than was envisaged by prescriptive texts of the period. Or rather, the letters provide evidence that Margherita and Francesco had a conventional enough view of how their relationship should be conducted, but the challenges of everyday life in an urban environment riven by factionalism and competitiveness forced them often to ignore the gender stereotypes of their day. Fourteenth-century advice manuals, such as Paola da Certaldo’s Libro di buoni costumi, described female virtue in narrow terms and demarcated the roles of husband and wife strictly, recommending that women be confined to the household and restrained from participating in men’s affairs. Margherita, however, collaborated in the supervision of Francesco’s building projects, even occasionally pursued the merchant’s debtors, and offered her husband shrewd advice, revealing the extent to which she was fully conversant with contemporary politics. She was cognizant of the need to participate in the social networking that was a fundamental feature of Florentine society and cultivated the magnate connections of her own aristocratic family to secure useful allies for the more humbly-born Francesco. Margherita’s inability to bear children was a source of bitter disappointment to the couple, but it indubitably facilitated her ability to take on a greater role in her husband’s affairs than was usual. The Datini couple’s letters also reveal many details about their households in Florence and Prato. The routines and experiences of the servants, neighbors, friends, and relatives with whom Margherita associated are documented in colloquial and evocative prose, providing a rare view of women’s social interactions and emotions in a period blighted by recurring outbreaks of plague, an unstable political climate, and difficult economic conditions.
London
Authors: Schen Claire
Published: July 2014

The city of London began as a Roman settlement along the River Thames and grew into Europe’s first urban area of a million inhabitants. London was unique within Britain, and in many ways in Europe, yet it was deeply intertwined with the provinces and other cities. The city’s location on a great river meant that goods, people, and ideas flowed into and out of the city for centuries, to or from the countryside as well as far-flung areas of the globe. London has exerted enormous influence over the other towns and cities of England and Great Britain, and has similarly been shaped by in-migration from these places and from abroad. London began to rebound to its pre-plague population levels by 1500 and proceeded to grow rapidly. The works included here talk variously of London, including its suburbs, and a metropolis, to describe its inexorable expansion across former fields and to the borders of neighbors. As it grew, its significance in the economy of the world, in its connections to empire and trade, became predominant and its merchants and investors carved a new place for themselves in British society. The city was not just important in economic terms to England, Britain, and eventually a global empire—it attracted and nourished intellectuals and artists, playwrights and writers, scientists and natural historians, and provided the setting for the display of status, consumption of new goods, and the development of fresh tastes. Positioned next to the political center of Westminster, it housed and provided a public stage for parliamentarians, political protesters, members of court, and the monarchy. At the same time, London provided opportunity to poor and un- or underemployed men and women to work, even if in professions or criminal activities outside or on the edges of social and moral norms of the period. For those who struggled, there was charity and beneficence, and punishment and forced work or separation from families. The focus on social and economic history that shaped historical writing of the 1960s into the 1980s elevated local history but influenced the questions asked of the metropolitan center. The last several decades have brought a resurgence of interest in the history of London, in the important religious, cultural, economic, social, and political developments that marked its transformation over a few hundred years.
Cable Television
Authors: Mullen Megan
Published: July 2014

In the United States, cable television refers to both a category of televised entertainment and information programming and the technological means of delivering that programming. In existence for over a half century, cable television has gone through a number of transformations—with regard to its uses, content, industry structure, and regulatory framework. Cable, at first known as community antenna television or CATV, was begun in the late 1940s and early 1950s as a means of redistributing broadcast television signals to small towns that were either too far from the stations originating those signals to receive them over the air, using set-top or even rooftop antennas, or were blocked from receiving the signals by mountains or other obstructions. Local entrepreneurs built very tall receiving towers and relayed the signals gathered there to local “subscribers” via wire for a monthly fee. It was not long before the CATV entrepreneurs came together to form a trade association and to share innovations and know-how. In the decades since, the cable industry (as it became known in the late 1960s) has faced a shifting and uncertain government policy climate. At first, cable was perceived as a threat to the broadcast television industry, both because of its ability to bypass nearby signals to retransmit the signals of better funded stations from larger markets and because some broadcasters claimed that cable systems were unfairly making money from programming that they themselves had paid for the rights to air. By the early 1970s, most of these concerns had abated, and by that point some very utopian expectations had instead been placed on the cable industry—nothing short of making up for the perceived public service failures of the commercial broadcast television system. This was known as the “blue sky” era. What actually emerged, during the late 1970s and early 1980s, were a number of satellite-delivered cable programming networks. These have not exactly addressed the utopian dreams of blue sky. However they eventually came to represent a range of programming niches that generally adhere to established broadcast program genres, which is not surprising given that they generally follow the same commercial imperatives as broadcast television. What is now known as cable television has the appeal to reach many more US households than it once did, even while still serving its initial retransmission function. These days cable itself competes with some very similar multichannel delivery technologies, including direct broadcast satellite, IPTV (high-speed Internet), and others. While these technologies, including cable itself, now are available globally, their existence is due to a range of political, economic, and cultural circumstances—most differing from those that allowed cable television to develop as it did in the United States (and in a somewhat different way in Canada).
Phrase Structure Grammars
Authors: Van Eynde Frank
Published: July 2014

Phrase structure grammars model the internal structure of a sentence in terms of a hierarchically organized representation. The sentence Every boy has a bike, for instance, is taken to consist of a noun phrase (every boy) and a verb phrase (has a bike), where the former consists of a determiner (every) and a noun (boy), and the latter of a verb (has) and a noun phrase (a bike), which, in turn, consists of a determiner (a) and a noun (bike). The structure is made explicit by labeled bracketing, as in (S (NP (Det every) (N boy)) (VP (V has) (NP (Det a) (N bike)))), or by a tree. Phrase structure grammars were introduced by Noam Chomsky in the 1950s, building on the tradition of Immediate Constituent Analysis in post-Bloomfieldian structuralism. They played a key role in Transformational Grammar (TG) till the late 1960s, mainly as a descriptive device. The shift toward generalization led to a more abstract version, widely known as X-bar syntax, a staple ingredient of generative syntax throughout the 1970s and the 1980s. The introduction of the Minimalist Program in the 1990s led to further abstraction, involving, among others, the virtual elimination of phrase structure rules. In Non-transformational Grammar, which has its origins in the 1970s, phrase structure grammars continue to thrive, especially in Lexical-Functional Grammar (LFG) and Head-Driven Phrase Structure Grammar (HPSG). While phrase structure grammars are mainly used in syntax, they also play a role in other areas of linguistics: they provide a structural backbone for the compositional interpretation of sentences in Semantics and for identifying prosodic units in Phonology. Their role in morphology is a bone of contention: in Transformational Grammar, the smallest units of analysis are morphemes, so that PS grammars extend below the word level. Non-transformational Grammars, by contrast, adopt a lexicalist stance and treat words as syntactic atoms, leaving the expression of sublexical regularities to other devices, such as lexical rules. The Formal Properties of phrase structure grammars have been studied in mathematical linguistics. They play a key role in computational linguistics and Natural Language Processing. Their relevance for the investigation of human language processing is studied in Psycholinguistics.
Cooperative Principle
Authors: Horn Laurence
Published: July 2014

The basis of Gricean pragmatics is the cooperative principle (CP): “Make your conversational contribution such as is required, at the stage at which it occurs, by the accepted purpose or direction of the talk exchange” (Grice 1989, cited under Foundational Works, p. 26). This general principle is instantiated by a set of Maxims of Conversation that govern rational interchange (see the separate Oxford Bibliographies article on Maxims of Conversation) and bridge the gap between what is said and what is meant. The CP and the maxims represent not sociological generalizations or prescriptions for proper conversational etiquette but baseline presumptions that, by their observance or their apparent violation, generate conversational implicatures. In saying p and implicating q, S[peaker] counts on H[earer]’s disposition to work out what was meant by S’s uttering p at a given point in the interaction, based on what was said, on how it was said, and on the interlocutors’ shared assumption that they are rational agents interacting cooperatively to reach a joint (or partially joint) goal. In particular, S assumes H will assume that S’s conversational contribution is truthful, informative, relevant, and perspicuous, even when that assumption cannot be directly sustained at the surface of the utterance. While implicature is an aspect of speaker meaning and not of utterance interpretation, it is S’s assumption that H will draw the appropriate inference based on taking CP as a touchstone that makes implicature recovery a rational expectation. (Implicature is used in this article to stand for Grice’s conversational implicature; his notion of conventional implicature, which in many ways traces back to ideas of Frege’s, cannot be discussed here because of space limitations and because by definition it is entirely independent of CP.)
Artillery
Authors: Dastrup Boyd L.
Published: July 2014

During the early years of the 21st century, field artillery achieved unparalleled accuracy with the introduction of precision-guided munitions. Such munitions allowed a gun crew to hit a target with one round or to engage a target without adjusting fire as long as the target was precisely located. In Iraq and Afghanistan in the first decade of the 21st century, the US Army fired Excalibur precision munition from its 155-millimeter (mm) howitzers and the Guided Multiple Launch Rocket System precision munition from its Multiple Launch Rocket System to destroy insurgent safe houses and other pinpoint targets. This precision capability revolutionized field artillery because massing fire to compensate for the lack of accuracy dominated field artillery tactics since the late 18th century with the introduction of relatively light, mobile field guns to complement siege artillery, coast artillery, garrison artillery, and pack artillery. Precision artillery munitions gave armies, especially the US Army, the capability of destroying a target with minimal collateral damage, meaning the destruction of civilian property or deaths of noncombatants who were near the target but not part of the target. This precision came centuries after gunpowder siege artillery in the form of bombards and heavy cast-bronze cannons had replaced mechanical siege engines, such as trebuchets and onagers, as a means of battering down fortification walls and after European armies started employing lighter cannons on the battlefield.
Charlemagne
Authors: France John
Published: July 2014

Historians have always been fascinated by the life of Charlemagne and, in particular, deeply concerned to explain the enormous expansion of his dominions. In 768 he became joint ruler of the Frankish lands, but the death of his brother Carloman in 771 left him as sole ruler of the whole realm of his father Pepin III (b. 741–d. 768). By 774 he had made inroads into Saxony, conquered the old kingdom of the Lombards, and dominated the Italian Peninsula. Campaigns in Spain later led to the establishment of a frontier zone against the Islamic power there, while a long and bitter conflict enabled him to annex the lands of the hostile Saxons and to enforce their conversion to Christianity. He even launched campaigns deep into Central Europe, destroying the Avar power in what we now call Hungary though without being able to conquer the area. However, the sources for his reign, and most especially for its military aspects, are very limited and often difficult to use (see Source Studies). These difficulties are enormously increased by the general tenor of writing on Charlemagne and certain specific controversies that bear upon his reign. Almost all studies of Charlemagne are admiring: the only real exception is that of The Carolingian Empire: The Age of Charlemagne (Fichtenau 1957, cited under the Reign of Charlemagne). Indeed, the legend of Charlemagne, born from such admiration, enormously complicates our perception, and it remains powerful to this day. In addition, a whole new way of looking at the transition from the ancient to the medieval world has been inspired by The World of Late Antiquity: From Marcus Aurelius to Muhammad (Brown 1971, cited under the Context of Charlemagne’s Reign), which posited a gradual and perhaps essentially peaceful transition from Roman to medieval. This matters for military history because an optimistic view of the survival of Roman institutions affects what one may think of the ability of Charlemagne to raise and sustain armies, and it also suggests a continuity of discipline of the standing armies of Rome. In short, how the history of early medieval Europe is understood profoundly influences the understanding of Charlemagne’s inheritance from the past and, most particularly, his military institutions and resources.
Hebrew
Authors: Sadan Tsvi , Schwarzwald Ora
Published: July 2014

Hebrew belongs to the family of Semitic languages, which is part of the larger family of Afroasiatic languages. It spans more than three millennia, paralleling the history of the Jewish people—first in the Land of Israel, then in the Diaspora, and again in the Land of Israel and the State of Israel. It is customary to divide the language into the following four historical periods: Biblical Hebrew, Rabbinic Hebrew (also known as Mishnaic Hebrew), Medieval Hebrew, and Modern Hebrew (alternatively referred to as Contemporary Hebrew, Israeli Hebrew, or even simply Israeli). Two further divisions should also be noted: Hebrew of the Second Temple period, and oral traditions of Hebrew. Biblical Hebrew in its narrow sense (c. 1000–530 bce) is attested mainly in the pre-exilic books of the Hebrew Bible. Hebrew in the Second Temple period (530 bce–70 ce) is a transient stage between Biblical Hebrew and Rabbinic Hebrew; the post-exilic books of the Hebrew Bible and the Dead Sea Scrolls are its main corpora. Rabbinic Hebrew (70–c. 500 ce) is further divided, according to whether it was still spoken or not, into Tannaitic Hebrew or Rabbinic Hebrew I (70–c. 200 ce), which is the language of the Mishna, and Amoraic Hebrew or Rabbinic Hebrew II (c. 200–500 ce), which is the language of the Hebrew part of the Palestinian and Babylonian Talmuds. Medieval Hebrew (c. 500–c. 1850) includes various works of poetry and prose produced in major Jewish communities. Oral traditions of Hebrew refer to recitations of the Hebrew Bible and the Mishna in traditional Jewish communities after Biblical Hebrew and Rabbinic Hebrew ceased to be spoken; these traditions are still preserved among certain circles. Modern Hebrew in its narrow sense (c. 1850 to the present) is a planned and unplanned amalgam of the earlier phases of Hebrew (as well as Jewish Aramaic), with a heavy grammatical and lexical influence from Yiddish, Russian, etc. It now fulfills all the social functions of a modern society, both in speech and in writing as well as online. It is also an important lingua franca of Hebrew linguistics (and many other areas of Jewish studies). In each of these divisions of Hebrew, as well as in the first group of sections (dealing with the language in general), selected important works in the following areas are mentioned, where relevant: encyclopedia, introductory works, dictionaries, bibliographies, journals, collected works, history, writing system, language “revival,” grammar in general, (articulatory) phonetics, phonology, morphology, syntax, semantics, pragmatics, discourse analysis, (meta-)lexicography, onomastics, sociolinguistics, psycholinguistics, and the spoken language.
Indirect evidence for elastic energy playing a role in limb recovery during toad hopping
Authors: Schnyer Ariela , Gallardo Mirialys , Cox Suzanne , Gillis Gary
Published: July 2014

Elastic energy is critical for amplifying muscle power during the propulsive phase of anuran jumping. In this study, we use toads (Bufo marinus) to address whether elastic recoil is also involved after take-off to help flex the limbs before landing. The potential for such spring-like behaviour stems from the unusually flexed configuration of a toad's hindlimbs in a relaxed state. Manual extension of the knee beyond approximately 90° leads to the rapid development of passive tension in the limb as underlying elastic tissues become stretched. We hypothesized that during take-off, the knee regularly extends beyond this, allowing passive recoil to help drive limb flexion in mid-air. To test this, we used high-speed video and electromyography to record hindlimb kinematics and electrical activity in a hindlimb extensor (semimembranosus) and flexor (iliofibularis). We predicted that hops in which the knees extended further during take-off would require less knee flexor recruitment during recovery. Knees extended beyond 90° in over 80% of hops, and longer hops involved greater degrees of knee extension during take-off and more intense semimembranosus activity. However, knee flexion velocities during recovery were maintained despite a significant decrease in iliofibularis intensity in longer hops, results consistent with elastic recoil playing a role.
Nonlinear Poisson effects in soft honeycombs
Authors: Mihai L. Angela , Goriely Alain
Published: July 2014

We examine solid cellular structures within the theoretical framework of finite elasticity, whereby we assume that the cell wall material is nonlinear elastic. This enables us to identify new mechanical effects that appear in cellular materials when elastically deformed, and to explore the physical properties that influence them. We find that, when a honeycomb structure of hyperelastic material and standard geometry, such as rectangular-, hexagonal- or diamond-shaped cells, contains walls which are inclined relative to an applied uniaxial tensile load, these walls tend to expand both in the direction of the load and in the perpendicular direction, producing an apparent negative Poisson's ratio at local cell level. Moreover, we show that this (negative) Poisson ratio decreases as the magnitude of the tensile load increases. For these structures, Poisson's ratios greater than 0.5 are obtained in uniaxial compression. Similar effects in structures with linearly elastic cell walls do not occur.
The geometry of discombinations and its applications to semi-inverse problems in anelasticity
Authors: Yavari Arash , Goriely Alain
Published: July 2014

The geometrical formulation of continuum mechanics provides us with a powerful approach to understand and solve problems in anelasticity where an elastic deformation is combined with a non-elastic component arising from defects, thermal stresses, growth effects or other effects leading to residual stresses. The central idea is to assume that the material manifold, prescribing the reference configuration for a body, has an intrinsic, non-Euclidean, geometrical structure. Residual stresses then naturally arise when this configuration is mapped into Euclidean space. Here, we consider the problem of discombinations (a new term that we introduce in this paper), that is, a combined distribution of fields of dislocations, disclinations and point defects. Given a discombination, we compute the geometrical characteristics of the material manifold (curvature, torsion, non-metricity), its Cartan's moving frames and structural equations. This identification provides a powerful algorithm to solve semi-inverse problems with non-elastic components. As an example, we calculate the residual stress field of a cylindrically symmetric distribution of discombinations in an infinite circular cylindrical bar made of an incompressible hyperelastic isotropic elastic solid.
A texture-processing model of the ‘visual sense of number’
Authors: Morgan M. J. , Raphael S. , Tibber M. S. , Dakin Steven C.
Published: July 2014

It has been suggested that numerosity is an elementary quality of perception, similar to colour. If so (and despite considerable investigation), its mechanism remains unknown. Here, we show that observers require on average a massive difference of approximately 40% to detect a change in the number of objects that vary irrelevantly in blur, contrast and spatial separation, and that some naive observers require even more than this. We suggest that relative numerosity is a type of texture discrimination and that a simple model computing the contrast energy at fine spatial scales in the image can perform at least as well as human observers. Like some human observers, this mechanism finds it harder to discriminate relative numerosity in two patterns with different degrees of blur, but it still outpaces the human. We propose energy discrimination as a benchmark model against which more complex models and new data can be tested.
Plasticity of fimbrial genotype and serotype within populations of Bordetella pertussis: analysis by paired flow cytometry and genome sequencing
Authors: Vaughan Thomas E. , Pratt Catherine B. , Sealey Katie , Preston Andrew , Fry Norman K. , Gorringe Andrew R.
Published: July 2014

The fimbriae of Bordetella pertussis are required for colonization of the human respiratory tract. Two serologically distinct fimbrial subunits, Fim2 and Fim3, considered important vaccine components for many years, are included in the Sanofi Pasteur 5-component acellular pertussis vaccine, and the World Health Organization recommends the inclusion of strains expressing both fimbrial serotypes in whole-cell pertussis vaccines. Each of the fimbrial major subunit genes, fim2, fim3, and fimX, has a promoter poly(C) tract upstream of its −10 box. Such monotonic DNA elements are susceptible to changes in length via slipped-strand mispairing in vitro and in vivo, which potentially causes on/off switching of genes at every cell division. Here, we have described intra-culture variability in poly(C) tract lengths and the resulting fimbrial phenotypes in 22 recent UK B. pertussis isolates. Owing to the highly plastic nature of fimbrial promoters, we used the same cultures for both genome sequencing and flow cytometry. Individual cultures of B. pertussis contained multiple fimbrial serotypes and multiple different fimbrial promoter poly(C) tract lengths, which supports earlier serological evidence that B. pertussis expresses both serotypes during infection.
Impact of the rtI187V polymerase substitution of hepatitis B virus on viral replication and antiviral drug susceptibility
Authors: Fan Jiyun , Wang Ying , Xiong Hui , Guo Xiaokui , Cheng Yung-chi
Published: July 2014

A high prevalence of the rtI187V polymerase substitution of hepatitis B virus (HBV) was detected in nucleoside/nucleotide-analogue-naive and -treated chronic hepatitis B (CHB) patients. We aimed at assessing the replicative capacity and susceptibility to lamivudine (LAM) and adefovir (ADV)in vitroof HBV harbouring rtI187V alone or in conjunction with LAM- or ADV-resistant mutations. The reverse transcriptase region of HBV isolates was directly sequenced from a cohort of 300 CHB patients from China. Replication-competent HBV constructs containing rtI187V and combined with LAM-resistant (rtM204I, rtL180M/rtM204V) mutations were generated, and compared with WT, LAM-resistant single (rtM204I) or double (rtL180M/rtM204V) and ADV-resistant (rtN236T) clones. In a Chinese cohort of 300 CHB patients, 8.7 % (26/300) showed substitution of rtI187 with V. Of note, the rtI187V prevalence in HBV genotype B was significantly higher than that in HBV genotype C (95.2 vs 4.8 %).In vitrophenotypic assays showed that the viruses bearing the rtI187V substitution had impaired replication efficacy when compared with the WT and the virus carrying rtI187V combined with LAM-resistant single or double mutations showed even more significantly impaired replicative capacities. Furthermore, rtI187V HBV remained susceptible towards treatment with LAM or ADVin vitrowhereas the combination of the rtI187V substitution with LAM-resistant mutations rendered HBV resistant to LAM but still sensitive to ADV. Our study revealed that the rtI187V substitution in the HBV polymerase frequently occurred in CHB patients, particularly those with HBV genotype B. However, the emergence of the rtI187V substitution significantly impaired viral replication but without affecting drug sensitivityin vitro.