Intermediate Structures

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Recent Advances in Modeling Fission Cross Sections over Intermediate Structures

Recent Advances in Modeling Fission Cross Sections over Intermediate Structures

The accurate, physics-based, and predictive modeling of fission cross sections above the resolved resonance range is the ultimate goal of our current efforts. Using Bjornholm- Lynn’s theory for the treatment of intermediate structures, model parameters extracted from modern theoretical nu- clear structure calculations, and a database of consistent parameters across isotopes, such modeling appears within reach. Our ongoing LANL-CEA collaboration is address- ing this topic with promising preliminary results, as shown in this paper. Obviously much work remains to encompass the full complexity (multi-dimensional, time-dependent, temperature-dependent) of the nuclear fission problem.

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Intermediate Structures in Fission and Consequences on Average Partial Cross Sections

Intermediate Structures in Fission and Consequences on Average Partial Cross Sections

evaluation codes. The impact of fission channel Intermediate Structures (IS) is well pictured by Fig. 1 which displayed the observed and current evaluated fission cross sections within the neutron-incident Unresolved Resonance energy Range (URR) for a fissile and a fertile isotope borrowed from the plutonium family. Below the fission threshold energy (E n < 500keV), we observe large manifestations

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The growth and composition of primary and community based care services  Metrics and evidence from the Italian National Health Service

The growth and composition of primary and community based care services Metrics and evidence from the Italian National Health Service

main groups of services: primary and ambulatory services, intermediate structures involving patient admission and two focused and specialized departments, namely Preven- tion and Public Health and Mental Healthcare, that are organizationally homogeneous in all the LHAs. Primary and ambulatory services consist of activities or processes that attempt to ensure primary assistance and continuity of care for patients without requiring any institutionalization. They include GPs, paediatricians, home healthcare and nursing home care, ambulatory mother and child services. Intermediate services, instead, are based on the physical presence of residential facilities and include services that aim to assist patients after their discharge from hospital, either in residential facilities for rehabilitation and long- term care or in ambulatory settings, such as structures for elderly people, disabled people, for rehabilitation and long- term care, hospice care. We decided then to keep distinct Table 5 Indicators of hospital and PCC services within each LHA of the sample (2007 data)

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MORPH-PRO: a novel algorithm and web server for protein morphing

MORPH-PRO: a novel algorithm and web server for protein morphing

algorithm produces a series of intermediate conforma- tions. We use linear interpolation, so that at each step every residue will move along the straight line between its current position and its ending position. Unfortu- nately, this can lead to biologically infeasible intermediate structures with atoms occupying the same space, incor- rect bond lengths, and incorrect bond angles. Therefore, we use the atom positions generated by linear interpo- lation as a first approximation to the correct solution, and use a dynamic programming algorithm to ensure that certain biological constraints are satisfied. This pro- duces structures which better resemble real proteins. Because these techniques are very efficient, our algo- rithm can produce many intermediate structures very quickly.

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Open IE as an Intermediate Structure for Semantic Tasks

Open IE as an Intermediate Structure for Semantic Tasks

Semantic applications typically extract in- formation from intermediate structures de- rived from sentences, such as dependency parse or semantic role labeling. In this pa- per, we study Open Information Extrac- tion’s (Open IE) output as an additional in- termediate structure and find that for tasks such as text comprehension, word similar- ity and word analogy it can be very effec- tive. Specifically, for word analogy, Open IE-based embeddings surpass the state of the art. We suggest that semantic applica- tions will likely benefit from adding Open IE format to their set of potential sentence- level structures.

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The Reovirus Mutant tsA279 L2 Gene Is Associated with Generation of a Spikeless Core Particle: Implications for Capsid Assembly

The Reovirus Mutant tsA279 L2 Gene Is Associated with Generation of a Spikeless Core Particle: Implications for Capsid Assembly

Virus assembly is an important late step in viral replication that is poorly understood in animal viruses. The mechanisms of viral assembly, release, extracellular transport, attachment, penetration, and uncoating determine the size and shape of the “packing crate” which must carry the viral genome between replicative cycles (40, 70). This packing crate must be a meta- stable structure to protect the genome during transport but also capable of releasing the genome and necessary associated replicative enzymes once it enters a new host cell. X-ray crys- tallography has provided valuable insight into the overall struc- ture and putative protein interactions in a number of viruses at a macromolecular level (47, 82). Recent studies have eluci- dated structural interactions of components such as the G-H loop of foot-and-mouth disease virion capsid protein VP1 (24) and the hemagglutinin of influenza virus expressed in a bacte- rial vector (46). Electron cryomicroscopic studies have utilized image averaging and various planes of focus to provide three- dimensional and, to a degree, internal imaging of whole-virus structures (6, 75, 77, 86), a limited number of subviral particles (28, 103), reassortant viruses (85), capsids assembled from expressed proteins (45), proteolytically degraded reovirus in- termediate structures (60), capsid-like structures produced by engineered and expressed rotavirus capsid protein VP2 (54), and reovirus and rotavirus undergoing in vitro transcription (53, 104). These studies showed complete structures and some assembly and disassembly intermediate structures, permit the localization of some proteins, and may identify regions of in- teractions between some proteins (60) and nucleic acids (77).

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Growing models of vertebrate limb development

Growing models of vertebrate limb development

mouse limbs. Schematics of how positional values (red, white and blue) are established that specify different proximodistal (PD) structures. (A) Apical ectodermal ridge (AER) removal in the chick wing at different stages leads to truncations, the extent of which depends on when the operation is performed (the earliest developmental stage is to the left). These results have been explained by two different models. (a) Progress zone model of chick wing PD patterning (Summerbell et al., 1973). Positional values are specified depending on the length of time cells remain in the distal progress zone (the right-hand side of the field in the figure). Cells that are displaced first from the progress zone form the humerus (blue), followed by forearm (white) and finally digits (red). AER removal terminates progress zone activity (shown by the loss of the white and red values). (b) Early specification model of chick wing PD patterning (Dudley et al., 2002). All three positional values, humerus (blue), forearm (white) and digits (red) are specified in the early chick wing bud prior to outgrowth and are expanded by growth. An alternative explanation for the limb truncations that follow AER removal is that cell death eliminates distal pre-specified positional values (crosses). Outcomes of some genetic experiments in the mouse have also supported this model (see main text for references and details). (B) Intercalation model of mouse limb PD patterning (Mariani et al., 2008). Reducing FGF activity in the AER of the mouse limb can lead to loss of intermediate structures, while distal and proximal structures still form (as shown in schematic of the skeleton), suggesting that

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Nanoparticles isolated from blood: a reflection of vesiculability of blood cells during the isolation process

Nanoparticles isolated from blood: a reflection of vesiculability of blood cells during the isolation process

exhibited filopodia and distortion compared with the rest- ing discocyte shape in the human and the mare (Figure 5B and E). The shapes of the nanoparticles were the same at all temperatures (Figure 5G–I). However, their mean size measured in human by flow cytometry (Table 4) and in the mare by scanning electron microscopy (Table 5) was depen- dent on the isolation temperature. As shown in Table 4, the increase in size with increasing temperature was gradual in all subjects (all data included). The differences between the size of nanoparticles isolated from mare’s blood at 20 ° C and 37 ° C and at 30 ° C and 37 ° C were considerable (29% and 22%, respectively). These differences were statistically significant (P , 0.0001) and of sufficient power (P values at α = 0.05 were 0.99 and 0.96, respectively) (Table 5). All the differences between the mean size of nanoparticles isolated from human blood at 4, 20, and 37 ° C and measured by flow cytometry were shown to be statistically significant (Table 4). The large size of nanoparticles in the isolates, the shapes of the intermediate structures leading to isolated material, and the sensitivity of the concentration and mean size of nanoparticles to external parameters such as temperature indicate that a large pool of nanoparticles were created after blood sampling.

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Determining the Reactivity and Oxidation Intermediates of an Allylnickel (N-Heterocyclic Carbene) Chloride Complex

Determining the Reactivity and Oxidation Intermediates of an Allylnickel (N-Heterocyclic Carbene) Chloride Complex

PVK in ~1:1 ratios in moderate to good yields as determined by GC-FID; and are consistent with samples at a higher concentration. From these studies, MeCN gave the highest conversion (~90%), while pyridine showed increased selectivity for CA, presumably through coordination to the intermediate structures. The attempted catalysis of allylbenzene with 4 as the catalyst was attempted at high and low temperatures and with additional base in both MeCN and pyridine, with no turnover observed by GC-FID. This reaction was also conducted neat and in DCM at –50 °C, with no turnover observed by GC-FID. The substrate was changed to cinnamyl pinacolborane with 4 as the catalyst, as the byproduct B-O bond is stronger than the byproduct O-H bond, and provide a better thermodynamic driving force. However, there was no turnover observed by 1 H NMR spectroscopy. From these experiments, it was found that 4 was non-catalytic under the reported conditions. The most likely reason that 4 is non-catalytic is due to decomposition of the reactive intermediates. Whether this was through dimerization or deprotonation of the NHC ligand is currently unknown.

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Coordination chemistry of transition metal halides and carbonyl compounds

Coordination chemistry of transition metal halides and carbonyl compounds

Of the common organic solvents, only T.H.F. and Dl'SO were found to dissolve complex (III) to any appreciable extent. This made the collection of NNP. data difficult. The 1 H.N.M.R. spectrum of a d^-D” S0 solution of the complex contained a multiplet resonance at J.SSrfppm, due to the methylene backbone. A second resonance for the methylene backbone and a resonance for the -NKeg protons was not observed. These are presumably obscured by the peak due to the residual protons in the solvent (2.50<Sppm). The solution was not concentrated enough to obtain 1 ^C.N.1‘.R spectra. »ithout further data, structures such as (N) and (P) are purely speculative.

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The University City Interface: Plazas and Boulevards

The University City Interface: Plazas and Boulevards

It has become an increased challenge for designers to define the boundaries between the univer- sity and its surrounding city. The amount of space serving as a nexus between universities and urban areas is gradually increasing. This study defines such intermediate spaces as “the universi- ty-city interface”—areas that influence the university’s physical and functional connection to the surrounding city. The research presents comparative case studies of three universities in urban contexts—Harvard University, University of Pennsylvania, and Université Catholique de Louvain— by analyzing plazas and boulevards. These representative open spaces provide interfaces for both the university campuses and their surrounding cities. This paper analyzes design elements from the perspective of campus spatial structure, as well as locations and functions, to develop a com- parative checklist for plazas and boulevards. The results offer a set of urban design principles for university plazas and boulevards that could significantly improve the quality of the university-city relationship. While these checklists and principles may vary depending on circumstances, they can be useful starting points for initializing design processes.

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Order parameter and connectivity topology analysis of crystalline ceramics for nuclear waste immobilization

Order parameter and connectivity topology analysis of crystalline ceramics for nuclear waste immobilization

The topological signature observes changes in connectivity whereas Steinhardt parameters assess angular rearrangement. These do not necessarily occur over the same timescale and, usually, as here, the latter continues after the former has ceased. For the first 2 ps there are transient changes in topological signature which are short-lived, are difficult to quantify and quickly subside. Further connectivity changes depend on cation type. At 3 ps for Ti, the effects of the cascade diminish and there is little alteration in the signature, which is close to that of PYR, thereafter. For Gd, the topological signatures are still changing up to approximately 8 ps, as shown by the changes in the population of 6- and 8-rings. While the average population of 8-rings for Gd returns to the PYR value, the populations of 4- and 6-rings suggest an intermediate structure, consistent with the trends in Table 2. The Gd connectivity and possibly the Ti 6-ring population indicate a shift to a disordered anion sub-lattice.

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Incremental Predictive Parsing with TurboParser

Incremental Predictive Parsing with TurboParser

Most approaches to incremental parsing either incur a degradation of accuracy or they have to postpone decisions, yield- ing underspecified intermediate output. We present an incremental predictive depen- dency parser that is fast, accurate, and largely language independent. By extend- ing a state-of-the-art dependency parser, connected analyses for sentence prefixes are obtained, which even predict properties and the structural embedding of upcoming words. In contrast to other approaches, ac- curacy for complete sentence analyses does not decrease.

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Three Dimensional Shapes and Distributions of Long Period Stacking Ordered Structures in Mg97Zn1Gd2 Cast Alloys Characterized by Electron Tomography

Three Dimensional Shapes and Distributions of Long Period Stacking Ordered Structures in Mg97Zn1Gd2 Cast Alloys Characterized by Electron Tomography

The alloys that can give rise to LPSO structures in an as-cast state are termed as type I, and the aforementioned Mg-Zn-Y alloy is representative of this type. For example, in a Mg- 0.7 at%Zn-1.4 at%Y alloy, LPSO structures remain along grain boundaries and as particles inside the matrix even after solution treatment at 793 K. 7) On the other hand, those where LPSO do not form in as-cast state are so called type II alloy. For example, the Mg-Zn-Gd system belongs to this category. 8) In this alloy system, no LPSO phase exists in

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Computer simulations of liquid crystals

Computer simulations of liquid crystals

To conclude, we have observed attractive interactions between a single disclination line and a nanoparticle in close vicinity. When the nanoparticle’s position was fixed, the nearby disclination line was bending towards the particle to minimise elastic free energy; the particle itself was surrounded by an off-centre Saturn ring. When the particle was released, it moved towards the centre of the simulation box. This al- lowed the disclination line to become straight, which minimised its length and hence the energy associated with it. The particles trajectories were non-linear and highly dependent on the structure of the surrounding director field. Three equilibrium po- sitions were identified reflecting the three-fold symmetry of the director field. For a range of simulations with fixed nanoparticle positions the particle became entangled by the disclination line. When the particles were released, they rapidly disentangled suggesting that the entangled state is unstable for nanoparticles of the size studied here. In addition, intermediate defect structures were observed during transitions from the entangled to non-entangled structure and vice versa.

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Writing Javanese Script in HTML using Unicode True Type Font and JawaTeX

Writing Javanese Script in HTML using Unicode True Type Font and JawaTeX

Intermediate text is document with TeX/LaTeX code and syntax. The code and syntax will be used to transliterate split Latin string pattern that the Javanese character positions are known. Intermediate text is a text document with extension .tex that follows right rule to write Javanese character [6]. Example of intermediate text produce by JawaTex is presented below,

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Ullmann coupling reactions on Ag(111) and Ag(110); substrate influence on the formation of covalently coupled products and intermediate metal organic structures
Metal Organic Structures

Ullmann coupling reactions on Ag(111) and Ag(110); substrate influence on the formation of covalently coupled products and intermediate metal organic structures Metal Organic Structures

On-surface reactions based on Ullmann coupling are known to proceed on coinage-metal substrates (e.g. Au, Ag, Cu), with the chemistry of the surface strongly influencing the reaction progression. In addition, the topography of the surface may be expected to affect the local adsorption geometry of the reactants as well as the intermediate and final structures. Here, we investigate the effect of two different surface facets of silver, Ag(111) and Ag(110) on the formation of organometallic and covalent structures for Ullmann-type coupling reactions. Deposition of 4,4”-diiodo-m-terphenyl molecules onto either Ag(111) or Ag(110) surfaces leads to the scission of C-I bonds followed by the formation of organometallic zigzag structures, consisting of molecules connected by coordination bonds to Ag adatoms. The covalently coupled product is formed by annealing each surface, leading to the removal of Ag atoms and the formation of covalently bonded zigzag poly(m-phenylene) structures. Comparisons of the adsorption model of molecules on each surface before and after annealing reveal that on Ag(111), structures rearrange by rotation and elongation of bonds in order to become commensurate with the surface, whereas for the Ag(110) surface, the similarity in adsorption geometry of the intermediate and final states means that no rotation is required.

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The structures of Micrococcus lysodeikticus catalase, its ferryl intermediate (compound II) and NADPH complex

The structures of Micrococcus lysodeikticus catalase, its ferryl intermediate (compound II) and NADPH complex

In compound II the Fe atom moves 0.24 A Ê toward the sixth ligand. Tyr343 OH moves in concert by 0.28 A Ê , accompanied by small changes of the dihedral angle at CA. The distance between the sixth liganded O atom and the iron is 1.87 A Ê (during re®nement this distance was not restrained and van der Waals repulsion for this particular pair of atoms was removed from the restraint list) compared with the 2.2±2.3 A Ê distance to the water in the resting state (Table 2). In the compound I and II PMC structures at low resolution (Gouet et al., 1996) this distance was restrained to be 1.71 A Ê . Inspection of the coordinates shows that in these structures there is distortion of the iron's octahedral coordination not found in MLC. The iron coordination seems to be near-ideal octahedral (Fig. 6). There is no signi®cant change in the iron±phenolic O distance in the two enzyme states. There is a movement of the iron relative to the pyrrole nitrogen plane. In the resting state, the deviation of the iron from the pyrrole nitrogen plane is 0.14 A Ê towards the proximal side and in compound II it is 0.04 A Ê towards the distal side of the haem.

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Paradigmatic Relations and Syntagmatic Relations: Are They Useful in learning Grammatical Structures?

Paradigmatic Relations and Syntagmatic Relations: Are They Useful in learning Grammatical Structures?

The history of grammar analysis goes back to the ancient Greeks, who transformed it from the art of writing and recognizing letters into a science of rules that govern the production of texts. Both the Greeks and Romans, who adopted the Greek analysis for Latin, used grammar to teach people how to use languages, which were then employed in many fields, such as politics, philosophy, and religion (Celce-Murcia, 1991; De Mauro, 2009). Then the investigation of Greek and Latin sentence structures spread on account of the innovation of printing, and numerous formal studies on language created. On the other hand, during the 17th century, there was an increment in the utilization of vernaculars and the investigation of languages concentrated on their utilization and not on their formal examination, as there was a strong interest in learning the languages of other countries. In the eighteenth century the distinction in the middle of implicit and explicit grammar developed, and in the nineteenth century, the formal investigation of traditional dialects assumed control once more. From that minute, a persistent swing between the significance of grammar utilization and formal examination has portrayed the historical backdrop of grammar (Celce-Murcia, 1991). As regards the present days, the concept of grammar is polysemous, as it can show the interior working of the phonetic framework; learners' unequivocal information of the language, which is portrayed by sentence structures; and the metalinguistic model used to depict that express learning (Giunchi, 1990).

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Three-dimensional Irregular Tree Modeling For Special Virtual Environments

Three-dimensional Irregular Tree Modeling For Special Virtual Environments

V IRTUAL environments play an important role in computer-generated movies and games. Natural phe- nomena such as trees, clouds, rivers, and mountains are commonly seen in the synthesized virtual worlds. However, it is a challenging task to create the models for these natural objects, due to their complicated structures and rich varia- tions. Three-dimensional tree modeling is a typical example. Trees have a hierarchical structure with different scales of branches such as the trunk, primary branches, and twigs. The global features such as the architecture and the distribution of branches, and the detail features such as branch shapes and gaps between branch clusters, vary much among different tree species. It is tedious and time-consuming to create a 3D tree by depicting these features manually.

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