C–H arylation of unsubstituted furan and thiophene with acceptor bromides: access to donor–acceptor–donor-type building blocks for organic electronics.

PubMed

Matsidik, Rukiya; Martin, Johannes; Schmidt, Simon; Obermayer, Johannes; Lombeck, Florian; Nübling, Fritz; Komber, Hartmut; Fazzi, Daniele; Sommer, Michael

2015-01-16

Pd-catalyzed direct arylation (DA) reaction conditions have been established for unsubstituted furan (Fu) and thiophene (Th) with three popular acceptor building blocks to be used in materials for organic electronics, namely 4,7-dibromo-2,1,3-benzothiadiazole (BTBr2), N,N′-dialkylated 2,6-dibromonaphthalene-1,4,5,8-bis(dicarboximide) (NDIBr2), and 1,4-dibromotetrafluorobenzene (F4Br2). Reactions with BTBr2, F4Br2, and NDIBr2 require different solvents to obtain high yields. The use of dimethylacetamide (DMAc) is essential for the successful coupling of BTBr2 and F4Br2, but detrimental for NDIBr2, as the electron-deficient NDI core is prone to nucleophilic core substitution in DMAc as solvent but not in toluene. NDIFu2 is much more planar compared to NDITh2, resulting in an enhanced charge-transfer character, which makes it an interesting building block for conjugated systems designed for organic electronics. This study highlights direct arylation as a simple and inexpensive method to construct a series of important donor–acceptor–donor building blocks to be further used for the preparation of a variety of conjugated materials.

Imaging and Quantitation of a Succession of Transient Intermediates Reveal the Reversible Self-Assembly Pathway of a Simple Icosahedral Virus Capsid.

PubMed

Medrano, María; Fuertes, Miguel Ángel; Valbuena, Alejandro; Carrillo, Pablo J P; Rodríguez-Huete, Alicia; Mateu, Mauricio G

2016-11-30

Understanding the fundamental principles underlying supramolecular self-assembly may facilitate many developments, from novel antivirals to self-organized nanodevices. Icosahedral virus particles constitute paradigms to study self-assembly using a combination of theory and experiment. Unfortunately, assembly pathways of the structurally simplest virus capsids, those more accessible to detailed theoretical studies, have been difficult to study experimentally. We have enabled the in vitro self-assembly under close to physiological conditions of one of the simplest virus particles known, the minute virus of mice (MVM) capsid, and experimentally analyzed its pathways of assembly and disassembly. A combination of electron microscopy and high-resolution atomic force microscopy was used to structurally characterize and quantify a succession of transient assembly and disassembly intermediates. The results provided an experiment-based model for the reversible self-assembly pathway of a most simple (T = 1) icosahedral protein shell. During assembly, trimeric capsid building blocks are sequentially added to the growing capsid, with pentamers of building blocks and incomplete capsids missing one building block as conspicuous intermediates. This study provided experimental verification of many features of self-assembly of a simple T = 1 capsid predicted by molecular dynamics simulations. It also demonstrated atomic force microscopy imaging and automated analysis, in combination with electron microscopy, as a powerful single-particle approach to characterize at high resolution and quantify transient intermediates during supramolecular self-assembly/disassembly reactions. Finally, the efficient in vitro self-assembly achieved for the oncotropic, cell nucleus-targeted MVM capsid may facilitate its development as a drug-encapsidating nanoparticle for anticancer targeted drug delivery.

Implementing the "Curriculum and Evaluation Standards."

ERIC Educational Resources Information Center

Pacyga, Robert

1994-01-01

Describes two activities to analyze unit-cell structures from a geometric viewpoint and invite students to apply their mathematical understanding to scientific phenomena. Students form models of the simple cube, a building block of crystalline structures, and a methane molecule. (MDH)

Microfibres and macroscopic films from the coordination-driven hierarchical self-assembly of cylindrical micelles

PubMed Central

Lunn, David J.; Gould, Oliver E. C.; Whittell, George R.; Armstrong, Daniel P.; Mineart, Kenneth P.; Winnik, Mitchell A.; Spontak, Richard J.; Pringle, Paul G.; Manners, Ian

2016-01-01

Anisotropic nanoparticles prepared from block copolymers are of growing importance as building blocks for the creation of synthetic hierarchical materials. However, the assembly of these structural units is generally limited to the use of amphiphilic interactions. Here we report a simple, reversible coordination-driven hierarchical self-assembly strategy for the preparation of micron-scale fibres and macroscopic films based on monodisperse cylindrical block copolymer micelles. Coordination of Pd(0) metal centres to phosphine ligands immobilized within the soluble coronas of block copolymer micelles is found to induce intermicelle crosslinking, affording stable linear fibres comprised of micelle subunits in a staggered arrangement. The mean length of the fibres can be varied by altering the micelle concentration, reaction stoichiometry or aspect ratio of the micelle building blocks. Furthermore, the fibres aggregate on drying to form robust, self-supporting macroscopic micelle-based thin films with useful mechanical properties that are analogous to crosslinked polymer networks, but on a longer length scale. PMID:27538877

Making Connections by Using Molecular Models in Geometry.

ERIC Educational Resources Information Center

Pacyga, Robert

1995-01-01

Describes two activities to analyze unit-cell structures from a geometric viewpoint and invites students to apply their mathematical understanding to scientific phenomena. Students form models of the simple cube, a building block of crystalline structures, and a methane molecule. (MKR)

Plasmid Vectors and Molecular Building Blocks for the Development of Genetic Manipulation Tools for Trypanosoma cruzi

PubMed Central

Bouvier, León A.; Cámara, María de los Milagros; Canepa, Gaspar E.; Miranda, Mariana R.; Pereira, Claudio A.

2013-01-01

The post genomic era revealed the need for developing better performing, easier to use and more sophisticated genetic manipulation tools for the study of Trypanosoma cruzi, the etiological agent of Chagas disease. In this work a series of plasmids that allow genetic manipulation of this protozoan parasite were developed. First of all we focused on useful tools to establish selection strategies for different strains and which can be employed as expression vectors. On the other hand molecular building blocks in the form of diverse selectable markers, modifiable fluorescent protein and epitope-tag coding sequences were produced. Both types of modules were harboured in backbone molecules conceived to offer multiple construction and sub-cloning strategies. These can be used to confer new properties to already available genetic manipulation tools or as starting points for whole novel designs. The performance of each plasmid and building block was determined independently. For illustration purposes, some simple direct practical applications were conducted. PMID:24205392

Biomimetic, Strong, Tough, and Self-Healing Composites Using Universal Sealant-Loaded, Porous Building Blocks.

PubMed

Hwang, Sung Hoon; Miller, Joseph B; Shahsavari, Rouzbeh

2017-10-25

Many natural materials, such as nacre and dentin, exhibit multifunctional mechanical properties via structural interplay between compliant and stiff constituents arranged in a particular architecture. Herein, we present, for the first time, the bottom-up synthesis and design of strong, tough, and self-healing composite using simple but universal spherical building blocks. Our composite system is composed of calcium silicate porous nanoparticles with unprecedented monodispersity over particle size, particle shape, and pore size, which facilitate effective loading and unloading with organic sealants, resulting in 258% and 307% increases in the indentation hardness and elastic modulus of the compacted composite. Furthermore, heating the damaged composite triggers the controlled release of the nanoconfined sealant into the surrounding area, enabling moderate recovery in strength and toughness. This work paves the path towards fabricating a novel class of biomimetic composites using low-cost spherical building blocks, potentially impacting bone-tissue engineering, insulation, refractory and constructions materials, and ceramic matrix composites.

Fuel-Mediated Transient Clustering of Colloidal Building Blocks.

PubMed

van Ravensteijn, Bas G P; Hendriksen, Wouter E; Eelkema, Rienk; van Esch, Jan H; Kegel, Willem K

2017-07-26

Fuel-driven assembly operates under the continuous influx of energy and results in superstructures that exist out of equilibrium. Such dissipative processes provide a route toward structures and transient behavior unreachable by conventional equilibrium self-assembly. Although perfected in biological systems like microtubules, this class of assembly is only sparsely used in synthetic or colloidal analogues. Here, we present a novel colloidal system that shows transient clustering driven by a chemical fuel. Addition of fuel causes an increase in hydrophobicity of the building blocks by actively removing surface charges, thereby driving their aggregation. Depletion of fuel causes reappearance of the charged moieties and leads to disassembly of the formed clusters. This reassures that the system returns to its initial, equilibrium state. By taking advantage of the cyclic nature of our system, we show that clustering can be induced several times by simple injection of new fuel. The fuel-mediated assembly of colloidal building blocks presented here opens new avenues to the complex landscape of nonequilibrium colloidal structures, guided by biological design principles.

Chemical Instrumentation for the Visually Handicapped.

ERIC Educational Resources Information Center

Anderson, James L.

1982-01-01

Describes a simple, relatively inexpensive, and easily implemented approach for introducing visually handicapped students to chemical instrumentation via experiments on operational amplifiers as examples of some of the electronic building blocks of chemical instrumentation. The approach is applicable to other chemical instruments having electrical…

Digital Morphing Wing: Active Wing Shaping Concept Using Composite Lattice-Based Cellular Structures.

PubMed

Jenett, Benjamin; Calisch, Sam; Cellucci, Daniel; Cramer, Nick; Gershenfeld, Neil; Swei, Sean; Cheung, Kenneth C

2017-03-01

We describe an approach for the discrete and reversible assembly of tunable and actively deformable structures using modular building block parts for robotic applications. The primary technical challenge addressed by this work is the use of this method to design and fabricate low density, highly compliant robotic structures with spatially tuned stiffness. This approach offers a number of potential advantages over more conventional methods for constructing compliant robots. The discrete assembly reduces manufacturing complexity, as relatively simple parts can be batch-produced and joined to make complex structures. Global mechanical properties can be tuned based on sub-part ordering and geometry, because local stiffness and density can be independently set to a wide range of values and varied spatially. The structure's intrinsic modularity can significantly simplify analysis and simulation. Simple analytical models for the behavior of each building block type can be calibrated with empirical testing and synthesized into a highly accurate and computationally efficient model of the full compliant system. As a case study, we describe a modular and reversibly assembled wing that performs continuous span-wise twist deformation. It exhibits high performance aerodynamic characteristics, is lightweight and simple to fabricate and repair. The wing is constructed from discrete lattice elements, wherein the geometric and mechanical attributes of the building blocks determine the global mechanical properties of the wing. We describe the mechanical design and structural performance of the digital morphing wing, including their relationship to wind tunnel tests that suggest the ability to increase roll efficiency compared to a conventional rigid aileron system. We focus here on describing the approach to design, modeling, and construction as a generalizable approach for robotics that require very lightweight, tunable, and actively deformable structures.

Digital Morphing Wing: Active Wing Shaping Concept Using Composite Lattice-Based Cellular Structures

PubMed Central

Jenett, Benjamin; Calisch, Sam; Cellucci, Daniel; Cramer, Nick; Gershenfeld, Neil; Swei, Sean

2017-01-01

Abstract We describe an approach for the discrete and reversible assembly of tunable and actively deformable structures using modular building block parts for robotic applications. The primary technical challenge addressed by this work is the use of this method to design and fabricate low density, highly compliant robotic structures with spatially tuned stiffness. This approach offers a number of potential advantages over more conventional methods for constructing compliant robots. The discrete assembly reduces manufacturing complexity, as relatively simple parts can be batch-produced and joined to make complex structures. Global mechanical properties can be tuned based on sub-part ordering and geometry, because local stiffness and density can be independently set to a wide range of values and varied spatially. The structure's intrinsic modularity can significantly simplify analysis and simulation. Simple analytical models for the behavior of each building block type can be calibrated with empirical testing and synthesized into a highly accurate and computationally efficient model of the full compliant system. As a case study, we describe a modular and reversibly assembled wing that performs continuous span-wise twist deformation. It exhibits high performance aerodynamic characteristics, is lightweight and simple to fabricate and repair. The wing is constructed from discrete lattice elements, wherein the geometric and mechanical attributes of the building blocks determine the global mechanical properties of the wing. We describe the mechanical design and structural performance of the digital morphing wing, including their relationship to wind tunnel tests that suggest the ability to increase roll efficiency compared to a conventional rigid aileron system. We focus here on describing the approach to design, modeling, and construction as a generalizable approach for robotics that require very lightweight, tunable, and actively deformable structures. PMID:28289574

AN EFFICIENT AQUEOUS N-HETEROCYCLIZATION OF ANILINE DERIVATIVES: MICROWAVE-ASSISTED SYNTHESIS OF N-ARYL AZACYCLOALKANES

EPA Science Inventory

N-aryl azacycloalkanes, an important class of building blocks in natural product and pharmaceuticals, are synthesized via an efficient and simple eco-friendly protocol that involves double N-alkylation of aniline derivatives. The reaction is accelerated by exposure to microwaves ...

What is Neptune's D/H ratio really telling us about its water abundance?

NASA Astrophysics Data System (ADS)

Ali-Dib, Mohamad; Lakhlani, Gunjan

2018-05-01

We investigate the deep-water abundance of Neptune using a simple two-component (core + envelope) toy model. The free parameters of the model are the total mass of heavy elements in the planet (Z), the mass fraction of Z in the envelope (fenv), and the D/H ratio of the accreted building blocks (D/Hbuild).We systematically search the allowed parameter space on a grid and constrain it using Neptune's bulk carbon abundance, D/H ratio, and interior structure models. Assuming solar C/O ratio and cometary D/H for the accreted building blocks are forming the planet, we can fit all of the constraints if less than ˜15 per cent of Z is in the envelope (f_{env}^{median} ˜ 7 per cent), and the rest is locked in a solid core. This model predicts a maximum bulk oxygen abundance in Neptune of 65× solar value. If we assume a C/O of 0.17, corresponding to clathrate-hydrates building blocks, we predict a maximum oxygen abundance of 200× solar value with a median value of ˜140. Thus, both cases lead to oxygen abundance significantly lower than the preferred value of Cavalié et al. (˜540× solar), inferred from model-dependent deep CO observations. Such high-water abundances are excluded by our simple but robust model. We attribute this discrepancy to our imperfect understanding of either the interior structure of Neptune or the chemistry of the primordial protosolar nebula.

High-performance thermoelectric nanocomposites from nanocrystal building blocks

PubMed Central

Ibáñez, Maria; Luo, Zhishan; Genç, Aziz; Piveteau, Laura; Ortega, Silvia; Cadavid, Doris; Dobrozhan, Oleksandr; Liu, Yu; Nachtegaal, Maarten; Zebarjadi, Mona; Arbiol, Jordi; Kovalenko, Maksym V.; Cabot, Andreu

2016-01-01

The efficient conversion between thermal and electrical energy by means of durable, silent and scalable solid-state thermoelectric devices has been a long standing goal. While nanocrystalline materials have already led to substantially higher thermoelectric efficiencies, further improvements are expected to arise from precise chemical engineering of nanoscale building blocks and interfaces. Here we present a simple and versatile bottom–up strategy based on the assembly of colloidal nanocrystals to produce consolidated yet nanostructured thermoelectric materials. In the case study on the PbS–Ag system, Ag nanodomains not only contribute to block phonon propagation, but also provide electrons to the PbS host semiconductor and reduce the PbS intergrain energy barriers for charge transport. Thus, PbS–Ag nanocomposites exhibit reduced thermal conductivities and higher charge carrier concentrations and mobilities than PbS nanomaterial. Such improvements of the material transport properties provide thermoelectric figures of merit up to 1.7 at 850 K. PMID:26948987

High-performance thermoelectric nanocomposites from nanocrystal building blocks.

PubMed

Ibáñez, Maria; Luo, Zhishan; Genç, Aziz; Piveteau, Laura; Ortega, Silvia; Cadavid, Doris; Dobrozhan, Oleksandr; Liu, Yu; Nachtegaal, Maarten; Zebarjadi, Mona; Arbiol, Jordi; Kovalenko, Maksym V; Cabot, Andreu

2016-03-07

The efficient conversion between thermal and electrical energy by means of durable, silent and scalable solid-state thermoelectric devices has been a long standing goal. While nanocrystalline materials have already led to substantially higher thermoelectric efficiencies, further improvements are expected to arise from precise chemical engineering of nanoscale building blocks and interfaces. Here we present a simple and versatile bottom-up strategy based on the assembly of colloidal nanocrystals to produce consolidated yet nanostructured thermoelectric materials. In the case study on the PbS-Ag system, Ag nanodomains not only contribute to block phonon propagation, but also provide electrons to the PbS host semiconductor and reduce the PbS intergrain energy barriers for charge transport. Thus, PbS-Ag nanocomposites exhibit reduced thermal conductivities and higher charge carrier concentrations and mobilities than PbS nanomaterial. Such improvements of the material transport properties provide thermoelectric figures of merit up to 1.7 at 850 K.

DOING Physics--Physics Activities for Groups.

ERIC Educational Resources Information Center

Zwicker, Earl, Ed.

1985-01-01

Students are challenged to investigate a simple electric motor and to build their own model from a battery, wood block, clips, enameled copper wire, bare wire, and sandpaper. Through trial and error, several discoveries are made, including a substitute commutator and use of a radio to detect motor armature contact changes. (DH)

Simple heuristics and rules of thumb: where psychologists and behavioural biologists might meet.

PubMed

Hutchinson, John M C; Gigerenzer, Gerd

2005-05-31

The Centre for Adaptive Behaviour and Cognition (ABC) has hypothesised that much human decision-making can be described by simple algorithmic process models (heuristics). This paper explains this approach and relates it to research in biology on rules of thumb, which we also review. As an example of a simple heuristic, consider the lexicographic strategy of Take The Best for choosing between two alternatives: cues are searched in turn until one discriminates, then search stops and all other cues are ignored. Heuristics consist of building blocks, and building blocks exploit evolved or learned abilities such as recognition memory; it is the complexity of these abilities that allows the heuristics to be simple. Simple heuristics have an advantage in making decisions fast and with little information, and in avoiding overfitting. Furthermore, humans are observed to use simple heuristics. Simulations show that the statistical structures of different environments affect which heuristics perform better, a relationship referred to as ecological rationality. We contrast ecological rationality with the stronger claim of adaptation. Rules of thumb from biology provide clearer examples of adaptation because animals can be studied in the environments in which they evolved. The range of examples is also much more diverse. To investigate them, biologists have sometimes used similar simulation techniques to ABC, but many examples depend on empirically driven approaches. ABC's theoretical framework can be useful in connecting some of these examples, particularly the scattered literature on how information from different cues is integrated. Optimality modelling is usually used to explain less detailed aspects of behaviour but might more often be redirected to investigate rules of thumb.

Biosynthesis of Modular Ascarosides in C. elegans

PubMed Central

Panda, Oishika; Akagi, Allison E.; Artyukhin, Alexander B.; Judkins, Joshua C.; Le, Henry H.; Mahanti, Parag; Cohen, Sarah M.; Sternberg, Paul W.

2017-01-01

The nematode Caenorhabditis elegans uses simple building blocks from primary metabolism and a strategy of modular assembly to build a great diversity of signaling molecules, the ascarosides, which function as a chemical language in this model organism. In the ascarosides, the dideoxysugar ascarylose serves as a scaffold to which diverse moieties from lipid, amino acid, neurotransmitter, and nucleoside metabolism are attached. However, the mechanisms that underlie the highly specific assembly of ascarosides are not understood. We show that the acyl-CoA synthetase ACS-7, which localizes to lysosome-related organelles, is specifically required for the attachment of different building blocks to the 4′-position of ascr#9. We further show that mutants lacking lysosome-related organelles are defective in the production of all 4′-modified ascarosides, thus identifying the waste disposal system of the cell as a hotspot for ascaroside biosynthesis. PMID:28371259

Using Container Structures in Architecture and Urban Design

NASA Astrophysics Data System (ADS)

Grębowski, Karol; Kałdunek, Daniel

2017-10-01

The paper presents the use of shipping containers in architecture and urban design. Even today, houses and apartments are still too expensive. Since 1923 architects have been improving the living conditions of citizens by building very simple, repeatable forms. With prefabrication technology it became possible to build quicker, causing house prices to decrease. Apartments in block of flats became affordable to more and more people. Modernism had great impact on the quality of living spaces, despite the detrimental effect of large panel technology on social life. It gave people their own bathrooms, and gifted them with simple solutions we now consider indispensable. The ambition to build cheaply but effectively is still here. The future of housing lies in prefabricated apartment modules. A well optimized creation process is the key, but taking into consideration the mistakes made by past generations should be the second most important factor. Studies show that large panel buildings were too monumental and solid for a housing structure, and offered no public spaces between them. Lack of urban design transformed a great idea into blocks that are considered to be ugly and unfriendly. Diversity is something that large panel structures were missing. While most block of flats were being constructed out of the same module (Model 770), differentiated architecture was difficult to achieve. Nowadays, increasing numbers of shipping containers are being used for housing purposes. These constructions show that it is possible to create astonishing housing with modules. Shipping containers were not designed to be a building material, but in contrast to large panel modules, there are many more possibilities of their transformation. In this paper the authors propose a set of rules that, if followed, would result in cheaper apartments, while keeping in consideration both tremendous architecture and friendly urban design. What is more, the proposed solution is designed to adapt to personalized requirements. In this paper the authors include information about design guidelines for structures made from shipping containers.

Impact force as a scaling parameter

NASA Technical Reports Server (NTRS)

Poe, Clarence C., Jr.; Jackson, Wade C.

1994-01-01

The Federal Aviation Administration (FAR PART 25) requires that a structure carry ultimate load with nonvisible impact damage and carry 70 percent of limit flight loads with discrete damage. The Air Force has similar criteria (MIL-STD-1530A). Both civilian and military structures are designed by a building block approach. First, critical areas of the structure are determined, and potential failure modes are identified. Then, a series of representative specimens are tested that will fail in those modes. The series begins with tests of simple coupons, progresses through larger and more complex subcomponents, and ends with a test on a full-scale component, hence the term 'building block.' In order to minimize testing, analytical models are needed to scale impact damage and residual strength from the simple coupons to the full-scale component. Using experiments and analysis, the present paper illustrates that impact damage can be better understood and scaled using impact force than just kinetic energy. The plate parameters considered are size and thickness, boundary conditions, and material, and the impact parameters are mass, shape, and velocity.

Modular and Orthogonal Synthesis of Hybrid Polymers and Networks

PubMed Central

Liu, Shuang; Dicker, Kevin T.; Jia, Xinqiao

2015-01-01

Biomaterials scientists strive to develop polymeric materials with distinct chemical make-up, complex molecular architectures, robust mechanical properties and defined biological functions by drawing inspirations from biological systems. Salient features of biological designs include (1) repetitive presentation of basic motifs; and (2) efficient integration of diverse building blocks. Thus, an appealing approach to biomaterials synthesis is to combine synthetic and natural building blocks in a modular fashion employing novel chemical methods. Over the past decade, orthogonal chemistries have become powerful enabling tools for the modular synthesis of advanced biomaterials. These reactions require building blocks with complementary functionalities, occur under mild conditions in the presence of biological molecules and living cells and proceed with high yield and exceptional selectivity. These chemistries have facilitated the construction of complex polymers and networks in a step-growth fashion, allowing facile modulation of materials properties by simple variations of the building blocks. In this review, we first summarize features of several types of orthogonal chemistries. We then discuss recent progress in the synthesis of step growth linear polymers, dendrimers and networks that find application in drug delivery, 3D cell culture and tissue engineering. Overall, orthogonal reactions and modulular synthesis have not only minimized the steps needed for the desired chemical transformations but also maximized the diversity and functionality of the final products. The modular nature of the design, combined with the potential synergistic effect of the hybrid system, will likely result in novel hydrogel matrices with robust structures and defined functions. PMID:25572255

Using OpenMP vs. Threading Building Blocks for Medical Imaging on Multi-cores

NASA Astrophysics Data System (ADS)

Kegel, Philipp; Schellmann, Maraike; Gorlatch, Sergei

We compare two parallel programming approaches for multi-core systems: the well-known OpenMP and the recently introduced Threading Building Blocks (TBB) library by Intel®. The comparison is made using the parallelization of a real-world numerical algorithm for medical imaging. We develop several parallel implementations, and compare them w.r.t. programming effort, programming style and abstraction, and runtime performance. We show that TBB requires a considerable program re-design, whereas with OpenMP simple compiler directives are sufficient. While TBB appears to be less appropriate for parallelizing existing implementations, it fosters a good programming style and higher abstraction level for newly developed parallel programs. Our experimental measurements on a dual quad-core system demonstrate that OpenMP slightly outperforms TBB in our implementation.

Interactive graphic editing tools in bioluminescent imaging simulation

NASA Astrophysics Data System (ADS)

Li, Hui; Tian, Jie; Luo, Jie; Wang, Ge; Cong, Wenxiang

2005-04-01

It is a challenging task to accurately describe complicated biological tissues and bioluminescent sources in bioluminescent imaging simulation. Several graphic editing tools have been developed to efficiently model each part of the bioluminescent simulation environment and to interactively correct or improve the initial models of anatomical structures or bioluminescent sources. There are two major types of graphic editing tools: non-interactive tools and interactive tools. Geometric building blocks (i.e. regular geometric graphics and superquadrics) are applied as non-interactive tools. To a certain extent, complicated anatomical structures and bioluminescent sources can be approximately modeled by combining a sufficient large number of geometric building blocks with Boolean operators. However, those models are too simple to describe the local features and fine changes in 2D/3D irregular contours. Therefore, interactive graphic editing tools have been developed to facilitate the local modifications of any initial surface model. With initial models composed of geometric building blocks, interactive spline mode is applied to conveniently perform dragging and compressing operations on 2D/3D local surface of biological tissues and bioluminescent sources inside the region/volume of interest. Several applications of the interactive graphic editing tools will be presented in this article.

Wind Movement Comparison Between Student Dormitory 2 and 3 ITERA and The Correlation Toward its Indoor Thermal Comfort

NASA Astrophysics Data System (ADS)

Perdana Khidmat, Rendy; Donny Koerniawan, M.; Suhendri

2018-05-01

Student dormitory is a semi-private building that designated to occupies large number of habitats. This type of building mostly designated in simple type of vertical housing. In the context of utilization, dormitory surely requires indoor thermal comfort yet in the same way it requires the energy efficiency as well. Building in a tropical climate country is expected to be adequate to adopt a potention from its surrounding in order to switch air conditioner and gain efficiency in energy consume. One of its key factors is wind. This paper tries to describe and investigate wind movement that works on two different type of student dormitory in Sumatera Institute of Technology. The distinct difference between two blocks is one of the tower block utilizes void meanwhile the other are not. This research is conducted by using Computational Fluid Dynamic (CFD) based software. This study is expected to provide an overview of the wind movement and its effect on air temperature and its correlation to the indoor thermal comfort in both buildings.

Titan's organic chemistry

NASA Technical Reports Server (NTRS)

Sagan, C.; Thompson, W. R.; Khare, B. N.

1985-01-01

Voyager discovered nine simple organic molecules in the atmosphere of Titan. Complex organic solids, called tholins, produced by irradiation of the simulated Titanian atmosphere, are consistent with measured properties of Titan from ultraviolet to microwave frequencies and are the likely main constituents of the observed red aerosols. The tholins contain many of the organic building blocks central to life on earth. At least 100-m, and possibly kms thicknesses of complex organics have been produced on Titan during the age of the solar system, and may exist today as submarine deposits beneath an extensive ocean of simple hydrocarbons.

Mathematical analysis of the 1D model and reconstruction schemes for magnetic particle imaging

NASA Astrophysics Data System (ADS)

Erb, W.; Weinmann, A.; Ahlborg, M.; Brandt, C.; Bringout, G.; Buzug, T. M.; Frikel, J.; Kaethner, C.; Knopp, T.; März, T.; Möddel, M.; Storath, M.; Weber, A.

2018-05-01

Magnetic particle imaging (MPI) is a promising new in vivo medical imaging modality in which distributions of super-paramagnetic nanoparticles are tracked based on their response in an applied magnetic field. In this paper we provide a mathematical analysis of the modeled MPI operator in the univariate situation. We provide a Hilbert space setup, in which the MPI operator is decomposed into simple building blocks and in which these building blocks are analyzed with respect to their mathematical properties. In turn, we obtain an analysis of the MPI forward operator and, in particular, of its ill-posedness properties. We further get that the singular values of the MPI core operator decrease exponentially. We complement our analytic results by some numerical studies which, in particular, suggest a rapid decay of the singular values of the MPI operator.

The Domino Way to Heterocycles

PubMed Central

Padwa, Albert; Bur, Scott K.

2007-01-01

Sequential transformations enable the facile synthesis of complex target molecules from simple building blocks in a single preparative step. Their value is amplified if they also create multiple stereogenic centers. In the ongoing search for new domino processes, emphasis is usually placed on sequential reactions which occur cleanly and without forming by-products. As a prerequisite for an ideally proceeding one-pot sequential transformation, the reactivity pattern of all participating components has to be such that each building block gets involved in a reaction only when it is supposed to do so. The development of sequences that combine transformations of fundamentally different mechanisms broadens the scope of such procedures in synthetic chemistry. This mini review contains a representative sampling from the last 15 years on the kinds of reactions that have been sequenced into cascades to produce heterocyclic molecules. PMID:17940591

Matriarch: A Python Library for Materials Architecture.

PubMed

Giesa, Tristan; Jagadeesan, Ravi; Spivak, David I; Buehler, Markus J

2015-10-12

Biological materials, such as proteins, often have a hierarchical structure ranging from basic building blocks at the nanoscale (e.g., amino acids) to assembled structures at the macroscale (e.g., fibers). Current software for materials engineering allows the user to specify polypeptide chains and simple secondary structures prior to molecular dynamics simulation, but is not flexible in terms of the geometric arrangement of unequilibrated structures. Given some knowledge of a larger-scale structure, instructing the software to create it can be very difficult and time-intensive. To this end, the present paper reports a mathematical language, using category theory, to describe the architecture of a material, i.e., its set of building blocks and instructions for combining them. While this framework applies to any hierarchical material, here we concentrate on proteins. We implement this mathematical language as an open-source Python library called Matriarch. It is a domain-specific language that gives the user the ability to create almost arbitrary structures with arbitrary amino acid sequences and, from them, generate Protein Data Bank (PDB) files. In this way, Matriarch is more powerful than commercial software now available. Matriarch can be used in tandem with molecular dynamics simulations and helps engineers design and modify biologically inspired materials based on their desired functionality. As a case study, we use our software to alter both building blocks and building instructions for tropocollagen, and determine their effect on its structure and mechanical properties.

Two Decades of Structure Building

PubMed Central

Gernsbacher, Morton Ann

2014-01-01

During the past decade I have been developing a very simple framework for describing the cognitive processes and mechanisms involved in discourse comprehension. I call this framework the Structure Building Framework, and it is based on evidence provided during the first decade of discourse processing research. According to the Structure Building Framework, the goal of comprehension is to build coherent mental representations or structures. Comprehenders build each structure by first laying a foundation. Comprehenders develop mental structures by mapping on new information when that information coheres or relates to previous information. However, when the incoming information is less related, comprehenders shift and attach a new substructure. The building blocks of mental structures are memory nodes, which are activated by incoming stimuli and controlled by two cognitive mechanisms: suppression and enhancement. In this article, first I review the seminal work on which the Structure Building Framework is based (the first decade of structure building research); then I recount the research I have conducted to test the Structure Building Framework (the second decade of structure building research). PMID:25484476

Implementation of Basic and Universal Gates In a single Circuit Based On Quantum-dot Cellular Automata Using Multi-Layer Crossbar Wire

NASA Astrophysics Data System (ADS)

Bhowmik, Dhrubajyoti; Saha, Apu Kr; Dutta, Paramartha; Nandi, Supratim

2017-08-01

Quantum-dot Cellular Automata (QCA) is one of the most substitutes developing nanotechnologies for electronic circuits, as a result of lower force utilization, higher speed and smaller size in correlation with CMOS innovation. The essential devices, a Quantum-dot cell can be utilized to logic gates and wires. As it is the key building block on nanotechnology circuits. By applying simple gates, the hardware requirements for a QCA circuit can be decreased and circuits can be less complex as far as level, delay and cell check. This article exhibits an unobtrusive methodology for actualizing novel upgraded simple and universal gates, which can be connected to outline numerous variations of complex QCA circuits. Proposed gates are straightforward in structure and capable as far as implementing any digital circuits. The main aim is to build all basic and universal gates in a simple circuit with and without crossbar-wire. Simulation results and physical relations affirm its handiness in actualizing each advanced circuit.

Catalytic allylic oxidation of internal alkenes to a multifunctional chiral building block

NASA Astrophysics Data System (ADS)

Bayeh, Liela; Le, Phong Q.; Tambar, Uttam K.

2017-07-01

The stereoselective oxidation of hydrocarbons is one of the most notable advances in synthetic chemistry over the past fifty years. Inspired by nature, enantioselective dihydroxylations, epoxidations and other oxidations of unsaturated hydrocarbons have been developed. More recently, the catalytic enantioselective allylic carbon-hydrogen oxidation of alkenes has streamlined the production of pharmaceuticals, natural products, fine chemicals and other functional materials. Allylic functionalization provides a direct path to chiral building blocks with a newly formed stereocentre from petrochemical feedstocks while preserving the olefin functionality as a handle for further chemical elaboration. Various metal-based catalysts have been discovered for the enantioselective allylic carbon-hydrogen oxidation of simple alkenes with cyclic or terminal double bonds. However, a general and selective allylic oxidation using the more common internal alkenes remains elusive. Here we report the enantioselective, regioselective and E/Z-selective allylic oxidation of unactivated internal alkenes via a catalytic hetero-ene reaction with a chalcogen-based oxidant. Our method enables non-symmetric internal alkenes to be selectively converted into allylic functionalized products with high stereoselectivity and regioselectivity. Stereospecific transformations of the resulting multifunctional chiral building blocks highlight the potential for rapidly converting internal alkenes into a broad range of enantioenriched structures that can be used in the synthesis of complex target molecules.

Multifunctional Nanoparticles Self-Assembled from Small Organic Building Blocks for Biomedicine.

PubMed

Xing, Pengyao; Zhao, Yanli

2016-09-01

Supramolecular self-assembly shows significant potential to construct responsive materials. By tailoring the structural parameters of organic building blocks, nanosystems can be fabricated, whose performance in catalysis, energy storage and conversion, and biomedicine has been explored. Since small organic building blocks are structurally simple, easily modified, and reproducible, they are frequently employed in supramolecular self-assembly and materials science. The dynamic and adaptive nature of self-assembled nanoarchitectures affords an enhanced sensitivity to the changes in environmental conditions, favoring their applications in controllable drug release and bioimaging. Here, recent significant research advancements of small-organic-molecule self-assembled nanoarchitectures toward biomedical applications are highlighted. Functionalized assemblies, mainly including vesicles, nanoparticles, and micelles are categorized according to their topological morphologies and functions. These nanoarchitectures with different topologies possess distinguishing advantages in biological applications, well incarnating the structure-property relationship. By presenting some important discoveries, three domains of these nanoarchitectures in biomedical research are covered, including biosensors, bioimaging, and controlled release/therapy. The strategies regarding how to design and characterize organic assemblies to exhibit biomedical applications are also discussed. Up-to-date research developments in the field are provided and research challenges to be overcome in future studies are revealed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Guiding principles for peptide nanotechnology through directed discovery.

PubMed

Lampel, A; Ulijn, R V; Tuttle, T

2018-05-21

Life's diverse molecular functions are largely based on only a small number of highly conserved building blocks - the twenty canonical amino acids. These building blocks are chemically simple, but when they are organized in three-dimensional structures of tremendous complexity, new properties emerge. This review explores recent efforts in the directed discovery of functional nanoscale systems and materials based on these same amino acids, but that are not guided by copying or editing biological systems. The review summarises insights obtained using three complementary approaches of searching the sequence space to explore sequence-structure relationships for assembly, reactivity and complexation, namely: (i) strategic editing of short peptide sequences; (ii) computational approaches to predicting and comparing assembly behaviours; (iii) dynamic peptide libraries that explore the free energy landscape. These approaches give rise to guiding principles on controlling order/disorder, complexation and reactivity by peptide sequence design.

Using music to study the evolution of cognitive mechanisms relevant to language.

PubMed

Patel, Aniruddh D

2017-02-01

This article argues that music can be used in cross-species research to study the evolution of cognitive mechanisms relevant to spoken language. This is because music and language share certain cognitive processing mechanisms and because music offers specific advantages for cross-species research. Music has relatively simple building blocks (tones without semantic properties), yet these building blocks are combined into rich hierarchical structures that engage complex cognitive processing. I illustrate this point with regard to the processing of musical harmonic structure. Because the processing of musical harmonic structure has been shown to interact with linguistic syntactic processing in humans, it is of interest to know if other species can acquire implicit knowledge of harmonic structure through extended exposure to music during development (vs. through explicit training). I suggest that domestic dogs would be a good species to study in addressing this question.

Hydrotalcite catalysis for the synthesis of new chiral building blocks.

PubMed

Rodilla, Jesus M; Neves, Patricia P; Pombal, Sofia; Rives, Vicente; Trujillano, Raquel; Díez, David

2016-01-01

The use of hydrotalcites for the synthesis of two chiral building blocks in a simple way is described as a new and green methodology. The synthesis of these compounds implies a regioselective Baeyer-Villiger reaction in a very selective way with ulterior opening and lactonisation. This methodology should be considered green for the use of hydrogen peroxide as the only oxidant and hydrotalcites as the catalyst, and because no residues are produced apart from water. The procedure is very adequate for using in gram scale, in order to increase the value of the obtained compounds. The conditions are excellent and can be applied for nonstable compounds, as they are very mild. The synthesised compounds are magnific starting materials for the synthesis of biologically active or natural compounds. The use of a cheap, commercial and chiral compound as carvone disposable in both enantiomeric forms adds an extra value to this methodology.

Hydrophobic duck feathers and their simulation on textile substrates for water repellent treatment.

PubMed

Liu, Yuyang; Chen, Xianqiong; Xin, J H

2008-12-01

Inspired by the non-wetting phenomena of duck feathers, the water repellent property of duck feathers was studied at the nanoscale. The microstructures of the duck feather were investigated by a scanning electron microscope (SEM) imaging method through a step-by-step magnifying procedure. The SEM results show that duck feathers have a multi-scale structure and that this multi-scale structure as well as the preening oil are responsible for their super hydrophobic behavior. The microstructures of the duck feather were simulated on textile substrates using the biopolymer chitosan as building blocks through a novel surface solution precipitation (SSP) method, and then the textile substrates were further modified with a silicone compound to achieve low surface energy. The resultant textiles exhibit super water repellent properties, thus providing a simple bionic way to create super hydrophobic surfaces on soft substrates using flexible material as building blocks.

Natural supramolecular building blocks: from virus coat proteins to viral nanoparticles.

PubMed

Liu, Zhi; Qiao, Jing; Niu, Zhongwei; Wang, Qian

2012-09-21

Viruses belong to a fascinating class of natural supramolecular structures, composed of multiple copies of coat proteins (CPs) that assemble into different shapes with a variety of sizes from tens to hundreds of nanometres. Because of their advantages including simple/economic production, well-defined structural features, unique shapes and sizes, genetic programmability and robust chemistries, recently viruses and virus-like nanoparticles (VLPs) have been used widely in biomedical applications and materials synthesis. In this critical review, we highlight recent advances in the use of virus coat proteins (VCPs) and viral nanoparticles (VNPs) as building blocks in self-assembly studies and materials development. We first discuss the self-assembly of VCPs into VLPs, which can efficiently incorporate a variety of different materials as cores inside the viral protein shells. Then, the self-assembly of VNPs at surfaces or interfaces is summarized. Finally, we discuss the co-assembly of VNPs with different functional materials (178 references).

A combinatorial code for pattern formation in Drosophila oogenesis.

PubMed

Yakoby, Nir; Bristow, Christopher A; Gong, Danielle; Schafer, Xenia; Lembong, Jessica; Zartman, Jeremiah J; Halfon, Marc S; Schüpbach, Trudi; Shvartsman, Stanislav Y

2008-11-01

Two-dimensional patterning of the follicular epithelium in Drosophila oogenesis is required for the formation of three-dimensional eggshell structures. Our analysis of a large number of published gene expression patterns in the follicle cells suggests that they follow a simple combinatorial code based on six spatial building blocks and the operations of union, difference, intersection, and addition. The building blocks are related to the distribution of inductive signals, provided by the highly conserved epidermal growth factor receptor and bone morphogenetic protein signaling pathways. We demonstrate the validity of the code by testing it against a set of patterns obtained in a large-scale transcriptional profiling experiment. Using the proposed code, we distinguish 36 distinct patterns for 81 genes expressed in the follicular epithelium and characterize their joint dynamics over four stages of oogenesis. The proposed combinatorial framework allows systematic analysis of the diversity and dynamics of two-dimensional transcriptional patterns and guides future studies of gene regulation.

A combined time-of-flight and depth-of-interaction detector for total-body positron emission tomography.

PubMed

Berg, Eric; Roncali, Emilie; Kapusta, Maciej; Du, Junwei; Cherry, Simon R

2016-02-01

In support of a project to build a total-body PET scanner with an axial field-of-view of 2 m, the authors are developing simple, cost-effective block detectors with combined time-of-flight (TOF) and depth-of-interaction (DOI) capabilities. This work focuses on investigating the potential of phosphor-coated crystals with conventional PMT-based block detector readout to provide DOI information while preserving timing resolution. The authors explored a variety of phosphor-coating configurations with single crystals and crystal arrays. Several pulse shape discrimination techniques were investigated, including decay time, delayed charge integration (DCI), and average signal shapes. Pulse shape discrimination based on DCI provided the lowest DOI positioning error: 2 mm DOI positioning error was obtained with single phosphor-coated crystals while 3-3.5 mm DOI error was measured with the block detector module. Minimal timing resolution degradation was observed with single phosphor-coated crystals compared to uncoated crystals, and a timing resolution of 442 ps was obtained with phosphor-coated crystals in the block detector compared to 404 ps without phosphor coating. Flood maps showed a slight degradation in crystal resolvability with phosphor-coated crystals; however, all crystals could be resolved. Energy resolution was degraded by 3%-7% with phosphor-coated crystals compared to uncoated crystals. These results demonstrate the feasibility of obtaining TOF-DOI capabilities with simple block detector readout using phosphor-coated crystals.

Bio-inspired Composites, a de novo Approach to the Conceptualization, Design and Synthesis of Tough Mesoscale Structures with Simple Building Blocks

DTIC Science & Technology

2013-02-01

41   4.4.1   Ordered arrangement of nanoporous silica – Decreasing sensitivity to cracks 44...materials become insensitive to flaws, thus enabling them to reach their theoretical strength irrespective of cracks or defects. Furthermore, in...highlighting the essential role of large stiffness-ratios in reducing crack tip stress concentrations in lamellar structures [32, 33]. Furthermore, a

Synthesis and evaluation of α-Ag2WO4 as novel antifungal agent

NASA Astrophysics Data System (ADS)

Foggi, Camila C.; Fabbro, Maria T.; Santos, Luís P. S.; de Santana, Yuri V. B.; Vergani, Carlos E.; Machado, Ana L.; Cordoncillo, Eloisa; Andrés, Juan; Longo, Elson

2017-04-01

Because of the need for new antifungal materials with greater potency, microcrystals of α-Ag2WO4, a complex metal oxide, have been synthetized by a simple co-precipitation method, and their antifungal activity against Candida albicans has been investigated. A theoretical model based on clusters that are building blocks of α-Ag2WO4 has been proposed to explain the experimental results.

Geometry of proteins: hydrogen bonding, sterics, and marginally compact tubes.

PubMed

Banavar, Jayanth R; Cieplak, Marek; Flammini, Alessandro; Hoang, Trinh X; Kamien, Randall D; Lezon, Timothy; Marenduzzo, Davide; Maritan, Amos; Seno, Flavio; Snir, Yehuda; Trovato, Antonio

2006-03-01

The functionality of proteins is governed by their structure in the native state. Protein structures are made up of emergent building blocks of helices and almost planar sheets. A simple coarse-grained geometrical model of a flexible tube barely subject to compaction provides a unified framework for understanding the common character of globular proteins. We argue that a recent critique of the tube idea is not well founded.

Geometry of proteins: Hydrogen bonding, sterics, and marginally compact tubes

NASA Astrophysics Data System (ADS)

Banavar, Jayanth R.; Cieplak, Marek; Flammini, Alessandro; Hoang, Trinh X.; Kamien, Randall D.; Lezon, Timothy; Marenduzzo, Davide; Maritan, Amos; Seno, Flavio; Snir, Yehuda; Trovato, Antonio

2006-03-01

The functionality of proteins is governed by their structure in the native state. Protein structures are made up of emergent building blocks of helices and almost planar sheets. A simple coarse-grained geometrical model of a flexible tube barely subject to compaction provides a unified framework for understanding the common character of globular proteins. We argue that a recent critique of the tube idea is not well founded.

Hierarchically nanostructured hydroxyapatite: hydrothermal synthesis, morphology control, growth mechanism, and biological activity

PubMed Central

Ma, Ming-Guo

2012-01-01

Hierarchically nanosized hydroxyapatite (HA) with flower-like structure assembled from nanosheets consisting of nanorod building blocks was successfully synthesized by using CaCl2, NaH2PO4, and potassium sodium tartrate via a hydrothermal method at 200°C for 24 hours. The effects of heating time and heating temperature on the products were investigated. As a chelating ligand and template molecule, the potassium sodium tartrate plays a key role in the formation of hierarchically nanostructured HA. On the basis of experimental results, a possible mechanism based on soft-template and self-assembly was proposed for the formation and growth of the hierarchically nanostructured HA. Cytotoxicity experiments indicated that the hierarchically nanostructured HA had good biocompatibility. It was shown by in-vitro experiments that mesenchymal stem cells could attach to the hierarchically nanostructured HA after being cultured for 48 hours. Objective The purpose of this study was to develop facile and effective methods for the synthesis of novel hydroxyapatite (HA) with hierarchical nanostructures assembled from independent and discrete nanobuilding blocks. Methods A simple hydrothermal approach was applied to synthesize HA by using CaCl2, NaH2PO4, and potassium sodium tartrate at 200°C for 24 hours. The cell cytotoxicity of the hierarchically nanostructured HA was tested by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Results HA displayed the flower-like structure assembled from nanosheets consisting of nanorod building blocks. The potassium sodium tartrate was used as a chelating ligand, inducing the formation and self-assembly of HA nanorods. The heating time and heating temperature influenced the aggregation and morphology of HA. The cell viability did not decrease with the increasing concentration of hierarchically nanostructured HA added. Conclusion A novel, simple and reliable hydrothermal route had been developed for the synthesis of hierarchically nanosized HA with flower-like structure assembled from nanosheets consisting of nanorod building blocks. The HA with the hierarchical nanostructure was formed via a soft-template assisted self-assembly mechanism. The hierarchically nanostructured HA has a good biocompatibility and essentially no in-vitro cytotoxicity. PMID:22619527

Synthesis of layered double hydroxide nanosheets by coprecipitation using a T-type microchannel reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pang, Xiujiang; Sun, Meiyu; Ma, Xiuming

The synthesis of Mg{sub 2}Al–NO{sub 3} layered double hydroxide (LDH) nanosheets by coprecipitation using a T-type microchannel reactor is reported. Aqueous LDH nanosheet dispersions were obtained. The LDH nanosheets were characterized by X-ray diffraction, transmission electron microscopy, atomic force microscopy and particle size analysis, and the transmittance and viscosity of LDH nanosheet dispersions were examined. The two-dimensional LDH nanosheets consisted of 1–2 brucite-like layers and were stable for ca. 16 h at room temperature. In addition, the co-assembly between LDH nanosheets and dodecyl sulfate (DS) anions was carried out, and a DS intercalated LDH nanohybrid was obtained. To the bestmore » of our knowledge, this is the first report of LDH nanosheets being directly prepared in bulk aqueous solution. This simple, cheap method can provide naked LDH nanosheets in high quantities, which can be used as building blocks for functional materials. - Graphical abstract: Layered double hydroxide (LDH) nanosheets were synthesized by coprecipitation using a T-type microchannel reactor, and could be used as basic building blocks for LDH-based functional materials. Display Omitted - Highlights: • LDH nanosheets were synthesized by coprecipitation using a T-type microchannel reactor. • Naked LDH nanosheets were dispersed in aqueous media. • LDH nanosheets can be used as building blocks for functional materials.« less

SRA Real Math Building Blocks PreK. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2007

2007-01-01

"SRA Real Math Building Blocks PreK" (also referred to as "Building Blocks for Math") is a supplemental mathematics curriculum designed to develop preschool children's early mathematical knowledge through various individual and small- and large-group activities. It uses "Building Blocks for Math PreK" software,…

Natural and engineered biosynthesis of nucleoside antibiotics in Actinomycetes.

PubMed

Chen, Wenqing; Qi, Jianzhao; Wu, Pan; Wan, Dan; Liu, Jin; Feng, Xuan; Deng, Zixin

2016-03-01

Nucleoside antibiotics constitute an important family of microbial natural products bearing diverse bioactivities and unusual structural features. Their biosynthetic logics are unique with involvement of complex multi-enzymatic reactions leading to the intricate molecules from simple building blocks. Understanding how nature builds this family of antibiotics in post-genomic era sets the stage for rational enhancement of their production, and also paves the way for targeted persuasion of the cell factories to make artificial designer nucleoside drugs and leads via synthetic biology approaches. In this review, we discuss the recent progress and perspectives on the natural and engineered biosynthesis of nucleoside antibiotics.

BRICK v0.2, a simple, accessible, and transparent model framework for climate and regional sea-level projections

NASA Astrophysics Data System (ADS)

Wong, Tony E.; Bakker, Alexander M. R.; Ruckert, Kelsey; Applegate, Patrick; Slangen, Aimée B. A.; Keller, Klaus

2017-07-01

Simple models can play pivotal roles in the quantification and framing of uncertainties surrounding climate change and sea-level rise. They are computationally efficient, transparent, and easy to reproduce. These qualities also make simple models useful for the characterization of risk. Simple model codes are increasingly distributed as open source, as well as actively shared and guided. Alas, computer codes used in the geosciences can often be hard to access, run, modify (e.g., with regards to assumptions and model components), and review. Here, we describe the simple model framework BRICK (Building blocks for Relevant Ice and Climate Knowledge) v0.2 and its underlying design principles. The paper adds detail to an earlier published model setup and discusses the inclusion of a land water storage component. The framework largely builds on existing models and allows for projections of global mean temperature as well as regional sea levels and coastal flood risk. BRICK is written in R and Fortran. BRICK gives special attention to the model values of transparency, accessibility, and flexibility in order to mitigate the above-mentioned issues while maintaining a high degree of computational efficiency. We demonstrate the flexibility of this framework through simple model intercomparison experiments. Furthermore, we demonstrate that BRICK is suitable for risk assessment applications by using a didactic example in local flood risk management.

Digital Alchemy for Materials Design: Colloids and Beyond

NASA Astrophysics Data System (ADS)

van Anders, Greg; Klotsa, Daphne; Karas, Andrew; Dodd, Paul; Glotzer, Sharon

Starting with the early alchemists, a holy grail of science has been to make desired materials by manipulating basic building blocks. Building blocks that show promise for assembling new complex materials can be synthesized at the nanoscale with attributes that would astonish the ancient alchemists in their versatility. However, this versatility means that connecting building-block attributes to bulk structure is both necessary for rationally engineering materials and difficult because building block attributes can be altered in many ways. We show how to exploit the malleability of colloidal nanoparticle ``elements'' to quantitatively link building-block attributes to bulk structure through a statistical thermodynamic framework we term ``digital alchemy''. We use this framework to optimize building blocks for a given target structure and to determine which building-block attributes are most important to control for self-assembly, through a set of novel thermodynamic response functions. We thereby establish direct links between the attributes of colloidal building blocks and the bulk structures they form. Moreover, our results give concrete solutions to the more general conceptual challenge of optimizing emergent behaviors in nature and can be applied to other types of matter.

Catalyst for Expanding Human Spaceflight

NASA Technical Reports Server (NTRS)

Lueders, Kathryn L.

2014-01-01

History supplies us with many models of how and how not to commercialize an industry. This presentation draws parallels between industries with government roots, like the railroad, air transport, communications and the internet, and NASAs Commercial Crew Program. In these examples, government served as a catalyst for what became a booming industry. The building block approach the Commercial Crew Program is taking is very simple -- establish a need, laying the groundwork, enabling industry and legal framework.

Gaussian curvature analysis allows for automatic block placement in multi-block hexahedral meshing.

PubMed

Ramme, Austin J; Shivanna, Kiran H; Magnotta, Vincent A; Grosland, Nicole M

2011-10-01

Musculoskeletal finite element analysis (FEA) has been essential to research in orthopaedic biomechanics. The generation of a volumetric mesh is often the most challenging step in a FEA. Hexahedral meshing tools that are based on a multi-block approach rely on the manual placement of building blocks for their mesh generation scheme. We hypothesise that Gaussian curvature analysis could be used to automatically develop a building block structure for multi-block hexahedral mesh generation. The Automated Building Block Algorithm incorporates principles from differential geometry, combinatorics, statistical analysis and computer science to automatically generate a building block structure to represent a given surface without prior information. We have applied this algorithm to 29 bones of varying geometries and successfully generated a usable mesh in all cases. This work represents a significant advancement in automating the definition of building blocks.

Nano-functionalization of protein microspheres

NASA Astrophysics Data System (ADS)

Yoon, Sungkwon; Nichols, William T.

2014-08-01

Protein microspheres are promising building blocks for the assembly of complex functional materials. Here we demonstrate a set of three techniques that add functionality to the surface of protein microspheres. In the first technique, a positive surface charge on the protein spheres is deposited by electrostatic adsorption. Negatively charged silica and gold nanoparticle colloids can then electrostatically bind reversibly to the microsphere surface. In the second technique, nanoparticles are covalently anchored to the protein shell using a simple one-pot process. The strong covalent bond between sulfur groups in cysteine in the protein shell irreversibly binds to the gold nanoparticles. In the third technique, surface morphology of the protein microsphere is tuned through hydrodynamic instability at the water-oil interface. This is accomplished through the degree of solubility of the oil phase in water. Taken together these three techniques form a platform to create nano-functionalized protein microspheres, which can then be used as building blocks for the assembly of more complex macroscopic materials.

Lock and Key Colloids through Polymerization-Induced Buckling of Monodispersed Silicon Oil Droplets

NASA Astrophysics Data System (ADS)

Sacanna, Stefano; Irvine, William T. M.; Chaikin, Paul M.; Pine, David J.

2010-03-01

Colloidal particles can spontaneously associate into larger structured aggregates when driven by selective and directional interactions. Colloidal organization can be programmed by engineering shapes and interactions of basic building blocks in a manner similar to molecular self-assembly. Examples of successful strategies that allow non-trivial assembly of particles include template-directed patterning, capillary forces and, most commonly, the functionalization of the particle surfaces with ``sticky patches'' of biological or synthetic molecules. The level of complexity of the realizable assemblies, increases when particles with well defined shape anisotropies are used. In particular depletion forces and specific surface treatments in combination with non spherical particles have proven to be powerful tools to self-assembly complex microstructures. We describe a simple, high yield, synthetic pathway to fabricate monodisperse hybrid silica spheres with well defined cavities. Because the particle morphologies are reproducible and tunable with precision, the resulting particles can be used as basic building blocks in the assembly of larger monodisperse clusters. This is demonstrated using depletion to drive the self-assembly.

Ring system-based chemical graph generation for de novo molecular design

NASA Astrophysics Data System (ADS)

Miyao, Tomoyuki; Kaneko, Hiromasa; Funatsu, Kimito

2016-05-01

Generating chemical graphs in silico by combining building blocks is important and fundamental in virtual combinatorial chemistry. A premise in this area is that generated structures should be irredundant as well as exhaustive. In this study, we develop structure generation algorithms regarding combining ring systems as well as atom fragments. The proposed algorithms consist of three parts. First, chemical structures are generated through a canonical construction path. During structure generation, ring systems can be treated as reduced graphs having fewer vertices than those in the original ones. Second, diversified structures are generated by a simple rule-based generation algorithm. Third, the number of structures to be generated can be estimated with adequate accuracy without actual exhaustive generation. The proposed algorithms were implemented in structure generator Molgilla. As a practical application, Molgilla generated chemical structures mimicking rosiglitazone in terms of a two dimensional pharmacophore pattern. The strength of the algorithms lies in simplicity and flexibility. Therefore, they may be applied to various computer programs regarding structure generation by combining building blocks.

Construction of conductive multilayer films of biogenic triangular gold nanoparticles and their application in chemical vapour sensing

NASA Astrophysics Data System (ADS)

Singh, Amit; Chaudhari, Minakshi; Sastry, Murali

2006-05-01

Metal nanoparticles are interesting building blocks for realizing films for a number of applications that include bio- and chemical sensing. To date, spherical metal nanoparticles have been used to generate functional electrical coatings. In this paper we demonstrate the synthesis of electrically conductive coatings using biologically prepared gold nanotriangles as the building blocks. The gold nanotriangles are prepared by the reduction of aqueous chloroaurate ions using an extract of the lemongrass plant (Cymbopogon flexuosus) which are thereafter assembled onto a variety of substrates by simple solution casting. The conductivity of the film shows a drastic fall upon mild heat treatment, leading to the formation of electrically conductive thin films of nanoparticles. We have also investigated the possibility of using the gold nanotriangle films in vapour sensing. A large fall in film resistance is observed upon exposure to polar molecules such as methanol, while little change occurs upon exposure to weakly polar molecules such as chloroform.

Multi-shape memory polymers achieved by the spatio-assembly of 3D printable thermoplastic building blocks.

PubMed

Li, Hongze; Gao, Xiang; Luo, Yingwu

2016-04-07

Multi-shape memory polymers were prepared by the macroscale spatio-assembly of building blocks in this work. The building blocks were methyl acrylate-co-styrene (MA-co-St) copolymers, which have the St-block-(St-random-MA)-block-St tri-block chain sequence. This design ensures that their transition temperatures can be adjusted over a wide range by varying the composition of the middle block. The two St blocks at the chain ends can generate a crosslink network in the final device to achieve strong bonding force between building blocks and the shape memory capacity. Due to their thermoplastic properties, 3D printing was employed for the spatio-assembly to build devices. This method is capable of introducing many transition phases into one device and preparing complicated shapes via 3D printing. The device can perform a complex action via a series of shape changes. Besides, this method can avoid the difficult programing of a series of temporary shapes. The control of intermediate temporary shapes was realized via programing the shapes and locations of building blocks in the final device.

A combined time-of-flight and depth-of-interaction detector for total-body positron emission tomography

PubMed Central

Berg, Eric; Roncali, Emilie; Kapusta, Maciej; Du, Junwei; Cherry, Simon R.

2016-01-01

Purpose: In support of a project to build a total-body PET scanner with an axial field-of-view of 2 m, the authors are developing simple, cost-effective block detectors with combined time-of-flight (TOF) and depth-of-interaction (DOI) capabilities. Methods: This work focuses on investigating the potential of phosphor-coated crystals with conventional PMT-based block detector readout to provide DOI information while preserving timing resolution. The authors explored a variety of phosphor-coating configurations with single crystals and crystal arrays. Several pulse shape discrimination techniques were investigated, including decay time, delayed charge integration (DCI), and average signal shapes. Results: Pulse shape discrimination based on DCI provided the lowest DOI positioning error: 2 mm DOI positioning error was obtained with single phosphor-coated crystals while 3–3.5 mm DOI error was measured with the block detector module. Minimal timing resolution degradation was observed with single phosphor-coated crystals compared to uncoated crystals, and a timing resolution of 442 ps was obtained with phosphor-coated crystals in the block detector compared to 404 ps without phosphor coating. Flood maps showed a slight degradation in crystal resolvability with phosphor-coated crystals; however, all crystals could be resolved. Energy resolution was degraded by 3%–7% with phosphor-coated crystals compared to uncoated crystals. Conclusions: These results demonstrate the feasibility of obtaining TOF–DOI capabilities with simple block detector readout using phosphor-coated crystals. PMID:26843254

A combined time-of-flight and depth-of-interaction detector for total-body positron emission tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berg, Eric, E-mail: eberg@ucdavis.edu; Roncali, Emilie; Du, Junwei

Purpose: In support of a project to build a total-body PET scanner with an axial field-of-view of 2 m, the authors are developing simple, cost-effective block detectors with combined time-of-flight (TOF) and depth-of-interaction (DOI) capabilities. Methods: This work focuses on investigating the potential of phosphor-coated crystals with conventional PMT-based block detector readout to provide DOI information while preserving timing resolution. The authors explored a variety of phosphor-coating configurations with single crystals and crystal arrays. Several pulse shape discrimination techniques were investigated, including decay time, delayed charge integration (DCI), and average signal shapes. Results: Pulse shape discrimination based on DCI providedmore » the lowest DOI positioning error: 2 mm DOI positioning error was obtained with single phosphor-coated crystals while 3–3.5 mm DOI error was measured with the block detector module. Minimal timing resolution degradation was observed with single phosphor-coated crystals compared to uncoated crystals, and a timing resolution of 442 ps was obtained with phosphor-coated crystals in the block detector compared to 404 ps without phosphor coating. Flood maps showed a slight degradation in crystal resolvability with phosphor-coated crystals; however, all crystals could be resolved. Energy resolution was degraded by 3%–7% with phosphor-coated crystals compared to uncoated crystals. Conclusions: These results demonstrate the feasibility of obtaining TOF–DOI capabilities with simple block detector readout using phosphor-coated crystals.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jadav, Mudra; Patel, Rajesh, E-mail: rjp@mkbhavuni.edu.in, E-mail: rpat7@yahoo.co

Here we present a technique using magnetic nanofluid to induce bidispersed suspension of nonmagnetic particles to assemble into colloidal chain, triangle, rectangle, ring-flower configurations. By changing the amplitude and direction of the magnetic field, we could tune the structure of nonmagnetic particles in magnetic nanofluid. The structures are assembled using magneto static interactions between effectively nonmagnetic particles dispersed in magnetizable magnetic nanofluid. The assembly of complex structures out of simple colloidal building blocks is of practical interest in photonic crystals and DNA biosensors.

Fullerene Derived Molecular Electronic Devices

NASA Technical Reports Server (NTRS)

Menon, Madhu; Srivastava, Deepak; Saini, Subbash

1998-01-01

The carbon Nanotube junctions have recently emerged as excellent candidates for use as the building blocks in the formation of nanoscale electronic devices. While the simple joint of two dissimilar tubes can be generated by the introduction of a pair of heptagon-pentagon defects in an otherwise perfect hexagonal grapheme sheet, more complex joints require other mechanisms. In this work we explore structural and electronic properties of complex 3-point junctions of carbon nanotubes using a generalized tight-binding molecular-dynamics scheme.

Providing pressure inputs to multizone building models

DOE PAGES

Herring, Steven J.; Batchelor, Simon; Bieringer, Paul E.; ...

2016-02-13

A study to assess how the fidelity of wind pressure inputs and indoor model complexity affect the predicted air change rate for a study building is presented. The purpose of the work is to support the development of a combined indoor-outdoor hazard prediction tool, which links the CONTAM multizone building simulation tool with outdoor dispersion models. The study building, representing a large office block of a simple rectangular geometry under natural ventilation, was based on a real building used in the Joint Urban 2003 experiment. A total of 1600 indoor model flow simulations were made, driven by 100 meteorological conditionsmore » which provided a wide range of building surface pressures. These pressures were applied at four levels of resolution to four different building configurations with varying numbers of internal zones and indoor and outdoor flow paths. Analysis of the results suggests that surface pressures and flow paths across the envelope should be specified at a resolution consistent with the dimensions of the smallest volume of interest, to ensure that appropriate outputs are obtained.« less

Data Policy Construction Set - Building Blocks from Childhood Constructions

NASA Astrophysics Data System (ADS)

Fleischer, Dirk; Paul-Stueve, Thilo; Jobmann, Alexandra; Farrenkopf, Stefan

2016-04-01

A complete construction set of building blocks usually comes with instructions and these instruction include building stages. The products of these building stages usually build from very general parts become highly specialized building parts for very unique features of the whole construction model. This sounds very much like the construction or organization of an interdisciplinary research project, institution or association, doesn't it! The creation process of an overarching data policy for a project group or institution is exactly the combination of individual interests with the common goal of a collaborative data policy and can be compared with the building stages of a construction set of building blocks and the building instructions. Keeping this in mind we created the data policy construction set of textual building blocks. This construction set is subdivided into several building stages or parts each containing multiple building blocks as text blocks. By combining building blocks of all subdivisions it is supposed to create a cascading data policy document. Cascading from the top level as a construction set provider for all further down existing levels such as project, themes, work packages or Universities, faculties, institutes down to the working level of working groups. The working groups are picking from the remaining building blocks in the provided construction set the suitable blocks for its working procedures to create a very specific policy from the available construction set provided by the top level community. Nevertheless, if a working group realized that there are missing building blocks or worse that there are missing building parts, then they have the chance to add the missing pieces to the construction set of direct an future use. This cascading approach enables project or institution wide application of the encoded rules from the textual level on access to data storage infrastructure. This structured approach is flexible enough to allow for the fact that interdisciplinary research projects always bring together very diverse amount of working habits, methods and requirements. All these need to be considered for the creation of the general document on data sharing and research data management. This approach focused on the recommendation of the RDA practical policy working group to implement practical policies derived from the textual level. Therefore it aims to move the data policy creation procedure and implementation towards the consortium or institutional formation with all the benefits of an existing data policy construction set already during the proposal creation and proposal review. Picking up the metaphor of real building blocks in context of data policies provides also the insight that existing building blocks and building parts can be reused as they are, but also can be redesigned with very little changes or a full overhaul.

The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers.

PubMed

Tian, Mi; Deng, Zhu; Meng, Zhaokun; Li, Rui; Zhang, Zhiyi; Qi, Wenhui; Wang, Rui; Yin, Tingting; Ji, Menghui

2018-01-01

Children's block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children's block building performance. Chinese preschoolers ( N = 180) participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children's block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation.

Urban Morphology Influence on Urban Albedo: A Revisit with the S olene Model

NASA Astrophysics Data System (ADS)

Groleau, Dominique; Mestayer, Patrice G.

2013-05-01

This heuristic study of the urban morphology influence on urban albedo is based on some 3,500 simulations with the S olene model. The studied configurations include square blocks in regular and staggered rows, rectangular blocks with different street widths, cross-shaped blocks, infinite street canyons and several actual districts in Marseilles, Toulouse and Nantes, France. The scanned variables are plan density, facade density, building height, layout orientation, latitude, date and time of the day. The sky-view factors of the ground and canopy surfaces are also considered. This study demonstrates the significance of the facade density, in addition to the built plan density, as the explanatory geometrical factor to characterize the urban morphology, rather than building height. On the basis of these albedo calculations the puzzling results of Kondo et al. (Boundary-Layer Meteorol 100:225-242, 2001) for the influence of building height are explained, and the plan density influence is quantitatively assessed. It is shown that the albedo relationship with plan and facade densities obtained with the regular square plot configuration may be considered as a reference for all other configurations, with the exception of the infinite street canyon that shows systematic differences for the lower plan densities. The curves representing this empirical relationship may be used as a sort of abacus for all other geometries while an approximate simple mathematical model is proposed, as well as relationships between the albedo and sky-view factors.

Analog Building Blocks for Communications Modems.

DTIC Science & Technology

1977-01-01

x*—*- A0-A039 82b ELECTRONIC COMMUNICATIONS INC ST PETERSBURG FLA F/6 9/5 ANALOG BUILDING BLOCKS FOR COMMUNICATIONS MODEMS .(U) JAN 77 B BLACK...F33615-7<t-C-1120 UNCLASSIFIED AFAL-TR-76-29 NL ANALOG BUILDING BLOCKS FOR COMMUNICATIONS MODEMS ELECTRONIC COMMUNICATIONS INC. A SUBSIDIARY OF...Idantltr Or Mac* numb*,; Avionics Building-Block modules Frequency Synthesize* Costas Demodulator Amplifier Modem Frequency Multiplier ’ -^ « TRACT

Fault-tolerant computer study. [logic designs for building block circuits

NASA Technical Reports Server (NTRS)

Rennels, D. A.; Avizienis, A. A.; Ercegovac, M. D.

1981-01-01

A set of building block circuits is described which can be used with commercially available microprocessors and memories to implement fault tolerant distributed computer systems. Each building block circuit is intended for VLSI implementation as a single chip. Several building blocks and associated processor and memory chips form a self checking computer module with self contained input output and interfaces to redundant communications buses. Fault tolerance is achieved by connecting self checking computer modules into a redundant network in which backup buses and computer modules are provided to circumvent failures. The requirements and design methodology which led to the definition of the building block circuits are discussed.

Adolescent Boys' and Girls' Block Constructions Differ in Structural Balance: A Block-Building Characteristic Related to Math Achievement

ERIC Educational Resources Information Center

Casey, Beth M.; Pezaris, Elizabeth E.; Bassi, Julie

2012-01-01

Two studies were conducted on block building in adolescents, assessing middle school (Study 1) and high school students (Study 2). Students were asked to build something interesting with blocks. In both samples, the same pattern of gender differences were found; boys built taller structures than girls, and balanced a larger number of blocks on a…

Aerial Imagery and LIDAR Data Fusion for Unambiguous Extraction of Adjacent Level-Buildings Footprints

NASA Astrophysics Data System (ADS)

Mola Ebrahimi, S.; Arefi, H.; Rasti Veis, H.

2017-09-01

Our paper aims to present a new approach to identify and extract building footprints using aerial images and LiDAR data. Employing an edge detector algorithm, our method first extracts the outer boundary of buildings, and then by taking advantage of Hough transform and extracting the boundary of connected buildings in a building block, it extracts building footprints located in each block. The proposed method first recognizes the predominant leading orientation of a building block using Hough transform, and then rotates the block according to the inverted complement of the dominant line's angle. Therefore the block poses horizontally. Afterwards, by use of another Hough transform, vertical lines, which might be the building boundaries of interest, are extracted and the final building footprints within a block are obtained. The proposed algorithm is implemented and tested on the urban area of Zeebruges, Belgium(IEEE Contest,2015). The areas of extracted footprints are compared to the corresponding areas in the reference data and mean error is equal to 7.43 m2. Besides, qualitative and quantitative evaluations suggest that the proposed algorithm leads to acceptable results in automated precise extraction of building footprints.

Composition of clusters and building blocks in amylopectins from maize mutants deficient in starch synthase III.

PubMed

Zhu, Fan; Bertoft, Eric; Seetharaman, Koushik

2013-12-18

Branches in amylopectin are distributed along the backbone. Units of the branches are building blocks (smaller) and clusters (larger) based on the distance between branches. In this study, composition of clusters and building blocks of amylopectins from dull1 maize mutants deficient in starch synthase III (SSIII) with a common genetic background (W64A) were characterized and compared with the wild type. Clusters were produced from amylopectins by partial hydrolysis using α-amylase of Bacillus amyloliquefaciens and were subsequently treated with phosphorylase a and β-amylase to produce φ,β-limit dextrins. Clusters were further extensively hydrolyzed with the α-amylase to produce building blocks. Structures of clusters and building blocks were analyzed by diverse chromatographic techniques. The results showed that the dull1 mutation resulted in larger clusters with more singly branched building blocks. The average cluster contained ~5.4 blocks in dull1 mutants and ~4.2 blocks in the wild type. The results are compared with previous results from SSIII-deficient amo1 barley and suggest fundamental differences in the cluster structures.

An installed nacelle design code using a multiblock Euler solver. Volume 2: User guide

NASA Technical Reports Server (NTRS)

Chen, H. C.

1992-01-01

This is a user manual for the general multiblock Euler design (GMBEDS) code. The code is for the design of a nacelle installed on a geometrically complex configuration such as a complete airplane with wing/body/nacelle/pylon. It consists of two major building blocks: a design module developed by LaRC using directive iterative surface curvature (DISC); and a general multiblock Euler (GMBE) flow solver. The flow field surrounding a complex configuration is divided into a number of topologically simple blocks to facilitate surface-fitted grid generation and improve flow solution efficiency. This user guide provides input data formats along with examples of input files and a Unix script for program execution in the UNICOS environment.

Combinatorics of γ-structures.

PubMed

Han, Hillary S W; Li, Thomas J X; Reidys, Christian M

2014-08-01

In this article we study canonical γ-structures, a class of RNA pseudoknot structures that plays a key role in the context of polynomial time folding of RNA pseudoknot structures. A γ-structure is composed of specific building blocks that have topological genus less than or equal to γ, where composition means concatenation and nesting of such blocks. Our main result is the derivation of the generating function of γ-structures via symbolic enumeration using so called irreducible shadows. We furthermore recursively compute the generating polynomials of irreducible shadows of genus ≤ γ. The γ-structures are constructed via γ-matchings. For 1 ≤ γ ≤ 10, we compute Puiseux expansions at the unique, dominant singularities, allowing us to derive simple asymptotic formulas for the number of γ-structures.

Engineering the formation of secondary building blocks within hollow interiors.

PubMed

Li, Xiaobo; Liu, Xiao; Ma, Yi; Li, Mingrun; Zhao, Jiao; Xin, Hongchuan; Zhang, Lei; Yang, Yan; Li, Can; Yang, Qihua

2012-03-15

Secondary building blocks within the cavities of primary silica-architecture building blocks are successfully engineered. The immobilized surfactant directs the selective dissolution and reassembly of dissolved silicate species for the formation of secondary building blocks (hollow nanospheres/nanorods; see figure). Supported TiO(2) on nanostructures with multilevel interiors is shown to exhibit significantly enhanced activity in photocatalytic H(2) production. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bayesian Estimation and Inference Using Stochastic Electronics

PubMed Central

Thakur, Chetan Singh; Afshar, Saeed; Wang, Runchun M.; Hamilton, Tara J.; Tapson, Jonathan; van Schaik, André

2016-01-01

In this paper, we present the implementation of two types of Bayesian inference problems to demonstrate the potential of building probabilistic algorithms in hardware using single set of building blocks with the ability to perform these computations in real time. The first implementation, referred to as the BEAST (Bayesian Estimation and Stochastic Tracker), demonstrates a simple problem where an observer uses an underlying Hidden Markov Model (HMM) to track a target in one dimension. In this implementation, sensors make noisy observations of the target position at discrete time steps. The tracker learns the transition model for target movement, and the observation model for the noisy sensors, and uses these to estimate the target position by solving the Bayesian recursive equation online. We show the tracking performance of the system and demonstrate how it can learn the observation model, the transition model, and the external distractor (noise) probability interfering with the observations. In the second implementation, referred to as the Bayesian INference in DAG (BIND), we show how inference can be performed in a Directed Acyclic Graph (DAG) using stochastic circuits. We show how these building blocks can be easily implemented using simple digital logic gates. An advantage of the stochastic electronic implementation is that it is robust to certain types of noise, which may become an issue in integrated circuit (IC) technology with feature sizes in the order of tens of nanometers due to their low noise margin, the effect of high-energy cosmic rays and the low supply voltage. In our framework, the flipping of random individual bits would not affect the system performance because information is encoded in a bit stream. PMID:27047326

Bayesian Estimation and Inference Using Stochastic Electronics.

PubMed

Thakur, Chetan Singh; Afshar, Saeed; Wang, Runchun M; Hamilton, Tara J; Tapson, Jonathan; van Schaik, André

2016-01-01

In this paper, we present the implementation of two types of Bayesian inference problems to demonstrate the potential of building probabilistic algorithms in hardware using single set of building blocks with the ability to perform these computations in real time. The first implementation, referred to as the BEAST (Bayesian Estimation and Stochastic Tracker), demonstrates a simple problem where an observer uses an underlying Hidden Markov Model (HMM) to track a target in one dimension. In this implementation, sensors make noisy observations of the target position at discrete time steps. The tracker learns the transition model for target movement, and the observation model for the noisy sensors, and uses these to estimate the target position by solving the Bayesian recursive equation online. We show the tracking performance of the system and demonstrate how it can learn the observation model, the transition model, and the external distractor (noise) probability interfering with the observations. In the second implementation, referred to as the Bayesian INference in DAG (BIND), we show how inference can be performed in a Directed Acyclic Graph (DAG) using stochastic circuits. We show how these building blocks can be easily implemented using simple digital logic gates. An advantage of the stochastic electronic implementation is that it is robust to certain types of noise, which may become an issue in integrated circuit (IC) technology with feature sizes in the order of tens of nanometers due to their low noise margin, the effect of high-energy cosmic rays and the low supply voltage. In our framework, the flipping of random individual bits would not affect the system performance because information is encoded in a bit stream.

The Impact of Individual Differences, Types of Model and Social Settings on Block Building Performance among Chinese Preschoolers

PubMed Central

Tian, Mi; Deng, Zhu; Meng, Zhaokun; Li, Rui; Zhang, Zhiyi; Qi, Wenhui; Wang, Rui; Yin, Tingting; Ji, Menghui

2018-01-01

Children’s block building performances are used as indicators of other abilities in multiple domains. In the current study, we examined individual differences, types of model and social settings as influences on children’s block building performance. Chinese preschoolers (N = 180) participated in a block building activity in a natural setting, and performance was assessed with multiple measures in order to identify a range of specific skills. Using scores generated across these measures, three dependent variables were analyzed: block building skills, structural balance and structural features. An overall MANOVA showed that there were significant main effects of gender and grade level across most measures. Types of model showed no significant effect in children’s block building. There was a significant main effect of social settings on structural features, with the best performance in the 5-member group, followed by individual and then the 10-member block building. These findings suggest that boys performed better than girls in block building activity. Block building performance increased significantly from 1st to 2nd year of preschool, but not from second to third. The preschoolers created more representational constructions when presented with a model made of wooden rather than with a picture. There was partial evidence that children performed better when working with peers in a small group than when working alone or working in a large group. It is suggested that future study should examine other modalities rather than the visual one, diversify the samples and adopt a longitudinal investigation. PMID:29441031

What Should We Make with CO 2 and How Can We Make It?

DOE PAGES

Bushuyev, Oleksandr S.; De Luna, Phil; Dinh, Cao Thang; ...

2018-03-29

In this forward-looking Perspective, we discuss the current state of technology and the economics of electrocatalytic transformation of CO 2 into various chemical fuels. Furthermore, our analysis finds that short-chain simple building-block molecules currently present the most economically compelling targets. Making an optimistic prediction of technology advancement in the future, we propose the gradual rise of photocatalytic, CO 2 polymerization, biohybrid, and molecular machine technologies to augment and enhance already practical electrocatalytic CO 2 conversion methods.

What Should We Make with CO 2 and How Can We Make It?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bushuyev, Oleksandr S.; De Luna, Phil; Dinh, Cao Thang

In this forward-looking Perspective, we discuss the current state of technology and the economics of electrocatalytic transformation of CO 2 into various chemical fuels. Furthermore, our analysis finds that short-chain simple building-block molecules currently present the most economically compelling targets. Making an optimistic prediction of technology advancement in the future, we propose the gradual rise of photocatalytic, CO 2 polymerization, biohybrid, and molecular machine technologies to augment and enhance already practical electrocatalytic CO 2 conversion methods.

Manganese-Mediated Coupling Reaction of Vinylarenes and Aliphatic Alcohols

PubMed Central

Zhang, Wei; Wang, Nai-Xing; Bai, Cui-Bing; Wang, Yan-Jing; Lan, Xing-Wang; Xing, Yalan; Li, Yi-He; Wen, Jia-Long

2015-01-01

Alcohols and alkenes are the most abundant and commonly used organic building blocks in the large-scale chemical synthesis. Herein, this is the first time to report a novel and operationally simple coupling reaction of vinylarenes and aliphatic alcohols catalyzed by manganese in the presence of TBHP (tert-butyl hydroperoxide). This coupling reaction provides the oxyalkylated products of vinylarenes with good regioselectivity and accomplishes with the principles of step-economies. A possible reaction mechanism has also been proposed. PMID:26470633

Dual function catalysts. Dehydrogenation and asymmetric intramolecular Diels-Alder cycloaddition of N-hydroxy formate esters and hydroxamic acids: evidence for a ruthenium-acylnitroso intermediate.

PubMed

Chow, Chun P; Shea, Kenneth J

2005-03-23

The chiral ruthenium salen complex, 13b, functions as an efficient catalyst for the sequential oxidation and asymmetric Diels-Alder cycloaddition of hydroxamic acids and N-hydroxy formate esters. This result provides evidence for the formation of a ruthenium-nitroso formate (acyl nitroso) intermediate. The Diels-Alder precursors are prepared from simple building blocks, and the cycloadducts, bridged oxazinolactams, can serve as useful intermediates in organic synthesis.

Using the World Health Organization health system building blocks through survey of healthcare professionals to determine the performance of public healthcare facilities.

PubMed

Manyazewal, Tsegahun

2017-01-01

Acknowledging the health system strengthening agenda, the World Health Organization (WHO) has formulated a health systems framework that describes health systems in terms of six building blocks. This study aimed to determine the current status of the six WHO health system building blocks in public healthcare facilities in Ethiopia. A quantitative, cross-sectional study was conducted in five public hospitals in central Ethiopia which were in a post-reform period. A self-administered, structured questionnaire which covered the WHO's six health system building blocks was used to collect data on healthcare professionals who consented. Data was analyzed using IBM SPSS version 20. The overall performance of the public hospitals was 60% when weighed against the WHO building blocks which, in this procedure, needed a minimum of 80% score. For each building block, performance scores were: information 53%, health workforce 55%, medical products and technologies 58%, leadership and governance 61%, healthcare financing 62%, and service delivery 69%. There existed a significant difference in performance among the hospitals ( p  < .001). The study proved that the WHO's health system building blocks are useful for assessing the process of strengthening health systems in Ethiopia. The six blocks allow identifying different improvement opportunities in each one of the hospitals. There was no contradiction between the indicators of the WHO building blocks and the health sustainable development goal (SDG) objectives. However, such SDG objectives should not be a substitute for strategies to strengthen health systems.

NANOSTRUCTURED METAL OXIDE CATALYSTS VIA BUILDING BLOCK SYNTHESES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craig E. Barnes

2013-03-05

A broadly applicable methodology has been developed to prepare new single site catalysts on silica supports. This methodology requires of three critical components: a rigid building block that will be the main structural and compositional component of the support matrix; a family of linking reagents that will be used to insert active metals into the matrix as well as cross link building blocks into a three dimensional matrix; and a clean coupling reaction that will connect building blocks and linking agents together in a controlled fashion. The final piece of conceptual strategy at the center of this methodology involves dosingmore » the building block with known amounts of linking agents so that the targeted connectivity of a linking center to surrounding building blocks is obtained. Achieving targeted connectivities around catalytically active metals in these building block matrices is a critical element of the strategy by which single site catalysts are obtained. This methodology has been demonstrated with a model system involving only silicon and then with two metal-containing systems (titanium and vanadium). The effect that connectivity has on the reactivity of atomically dispersed titanium sites in silica building block matrices has been investigated in the selective oxidation of phenols to benezoquinones. 2-connected titanium sites are found to be five times as active (i.e. initial turnover frequencies) than 4-connected titanium sites (i.e. framework titanium sites).« less

The Building Blocks of Geology.

ERIC Educational Resources Information Center

Gibson, Betty O.

2001-01-01

Discusses teaching techniques for teaching about rocks, minerals, and the differences between them. Presents a model-building activity that uses plastic building blocks to build crystal and rock models. (YDS)

Compartmentalization and Transport in Synthetic Vesicles

PubMed Central

Schmitt, Christine; Lippert, Anna H.; Bonakdar, Navid; Sandoghdar, Vahid; Voll, Lars M.

2016-01-01

Nanoscale vesicles have become a popular tool in life sciences. Besides liposomes that are generated from phospholipids of natural origin, polymersomes fabricated of synthetic block copolymers enjoy increasing popularity, as they represent more versatile membrane building blocks that can be selected based on their specific physicochemical properties, such as permeability, stability, or chemical reactivity. In this review, we focus on the application of simple and nested artificial vesicles in synthetic biology. First, we provide an introduction into the utilization of multicompartmented vesosomes as compartmentalized nanoscale bioreactors. In the bottom-up development of protocells from vesicular nanoreactors, the specific exchange of pathway intermediates across compartment boundaries represents a bottleneck for future studies. To date, most compartmented bioreactors rely on unspecific exchange of substrates and products. This is either based on changes in permeability of the coblock polymer shell by physicochemical triggers or by the incorporation of unspecific porin proteins into the vesicle membrane. Since the incorporation of membrane transport proteins into simple and nested artificial vesicles offers the potential for specific exchange of substances between subcompartments, it opens new vistas in the design of protocells. Therefore, we devote the main part of the review to summarize the technical advances in the use of phospholipids and block copolymers for the reconstitution of membrane proteins. PMID:26973834

The 10 building blocks of high-performing primary care.

PubMed

Bodenheimer, Thomas; Ghorob, Amireh; Willard-Grace, Rachel; Grumbach, Kevin

2014-01-01

Our experiences studying exemplar primary care practices, and our work assisting other practices to become more patient centered, led to a formulation of the essential elements of primary care, which we call the 10 building blocks of high-performing primary care. The building blocks include 4 foundational elements-engaged leadership, data-driven improvement, empanelment, and team-based care-that assist the implementation of the other 6 building blocks-patient-team partnership, population management, continuity of care, prompt access to care, comprehensiveness and care coordination, and a template of the future. The building blocks, which represent a synthesis of the innovative thinking that is transforming primary care in the United States, are both a description of existing high-performing practices and a model for improvement.

Two innovative solutions based on fibre concrete blocks designed for building substructure

NASA Astrophysics Data System (ADS)

Pazderka, J.; Hájek, P.

2017-09-01

Using of fibers in a high-strength concrete allows reduction of the dimensions of small precast concrete elements, which opens up new ways of solution for traditional construction details in buildings. The paper presents two innovative technical solutions for building substructure: The special shaped plinth block from fibre concrete and the fibre concrete elements for new technical solution of ventilated floor. The main advantages of plinth block from fibre concrete blocks (compared with standard plinth solutions) is: easier and faster assembly, higher durability and thanks to the air cavity between the vertical part of the block, the building substructure reduced moisture level of structures under the waterproofing layer and a comprehensive solution to the final surface of building plinth as well as the surface of adjacent terrain. The ventilated floor based on fibre concrete precast blocks is an attractive structural alternative for tackling the problem of increased moisture in masonry in older buildings, lacking a functional waterproof layer in the substructure.

Development of Test Article Building Block (TABB) for deployable platform systems

NASA Technical Reports Server (NTRS)

Greenberg, H. S.; Barbour, R. T.

1984-01-01

The concept of a Test Article Building Block (TABB) is described. The TABB is a ground test article that is representative of a future building block that can be used to construct LEO and GEO deployable space platforms for communications and scientific payloads. This building block contains a main housing within which the entire structure, utilities, and deployment/retraction mechanism are stowed during launch. The end adapter secures the foregoing components to the housing during launch. The main housing and adapter provide the necessary building-block-to-building-block attachments for automatically deployable platforms. Removal from the shuttle cargo bay can be accomplished with the remote manipulator system (RMS) and/or the handling and positioning aid (HAPA). In this concept, all the electrical connections are in place prior to launch with automatic latches for payload attachment provided on either the end adapters or housings. The housings also can contain orbiter docking ports for payload installation and maintenance.

Efficient Risk Determination of Risk of Road Blocking by Means of MMS and Data of Buildings and Their Surrounding

NASA Astrophysics Data System (ADS)

Nose, Kazuhito; Hatake, Shuhei

2016-06-01

Massive earthquake named "Tonankai Massive earthquake" is predicted to occur in the near future and is feared to cause severe damage in Kinki District . "Hanshin-Awaji Massive Earthquake" in 1995 destroyed most of the buildings constructed before 1981 and not complying with the latest earthquake resistance standards. Collapsed buildings blocked roads, obstructed evacuation, rescue and firefighting operations and inflicted further damages.To alleviate the damages, it is important to predict the points where collapsed buildings are likely block the roads and to take precautions in advance. But big cities have an expanse of urban areas with densely-distributed buildings, and it requires time and cost to check each and every building whether or not it will block the road. In order to reduce blocked roads when a disaster strikes, we made a study and confirmed that the risk of road blocking can be determined easily by means of the latest technologies of survey and geographical information.

Fabrication of Polyhedral Particles from Spherical Colloids and Their Self-Assembly into Rotator Phases**

PubMed Central

Vutukuri, Hanumantha Rao; Imhof, Arnout; van Blaaderen, Alfons

2014-01-01

Particle shape is a critical parameter that plays an important role in self-assembly, for example, in designing targeted complex structures with desired properties. Over the last decades, an unprecedented range of monodisperse nanoparticle systems with control over the shape of the particles have become available. In contrast, the choice of micrometer-sized colloidal building blocks of particles with flat facets, that is, particles with polygonal shapes, is significantly more limited. This can be attributed to the fact that in contrast to nanoparticles, the larger colloids are significantly harder to synthesize as single crystals. It is now shown that a very simple building block, such as a micrometer-sized polymeric spherical colloidal particle, is already enough to fabricate particles with regularly placed flat facets, including completely polygonal shapes with sharp edges. As an illustration that the yields are high enough for further self-assembly studies, the formation of three-dimensional rotator phases of fluorescently labelled, micrometer-sized, and charged rhombic dodecahedron particles was demonstrated. This method for fabricating polyhedral particles opens a new avenue for designing new materials. PMID:25366869

Supramolecular chemistry-general principles and selected examples from anion recognition and metallosupramolecular chemistry.

PubMed

Albrecht, Markus

2007-12-01

This review gives an introduction into supramolecular chemistry describing in the first part general principles, focusing on terms like noncovalent interaction, molecular recognition, self-assembly, and supramolecular function. In the second part those will be illustrated by simple examples from our laboratories. Supramolecular chemistry is the science that bridges the gap between the world of molecules and nanotechnology. In supramolecular chemistry noncovalent interactions occur between molecular building blocks, which by molecular recognition and self-assembly form (functional) supramolecular entities. It is also termed the "chemistry of the noncovalent bond." Molecular recognition is based on geometrical complementarity based on the "key-and-lock" principle with nonshape-dependent effects, e.g., solvatization, being also highly influential. Self-assembly leads to the formation of well-defined aggregates. Hereby the overall structure of the target ensemble is controlled by the symmetry features of the certain building blocks. Finally, the aggregates can possess special properties or supramolecular functions, which are only found in the ensemble but not in the participating molecules. This review gives an introduction on supramolecular chemistry and illustrates the fundamental principles by recent examples from our group.

Effects of Working Memory Capacity and Domain Knowledge on Recall for Grocery Prices.

PubMed

Bermingham, Douglas; Gardner, Michael K; Woltz, Dan J

2016-01-01

Hambrick and Engle (2002) proposed 3 models of how domain knowledge and working memory capacity may work together to influence episodic memory: a "rich-get-richer" model, a "building blocks" model, and a "compensatory" model. Their results supported the rich-get-richer model, although later work by Hambrick and Oswald (2005) found support for a building blocks model. We investigated the effects of domain knowledge and working memory on recall of studied grocery prices. Working memory was measured with 3 simple span tasks. A contrast of realistic versus fictitious foods in the episodic memory task served as our manipulation of domain knowledge, because participants could not have domain knowledge of fictitious food prices. There was a strong effect for domain knowledge (realistic food-price pairs were easier to remember) and a moderate effect for working memory capacity (higher working memory capacity produced better recall). Furthermore, the interaction between domain knowledge and working memory produced a small but significant interaction in 1 measure of price recall. This supported the compensatory model and stands in contrast to previous research.

Aliphatic hyperbranched polyester: A new building block in the construction of multifunctional nanoparticles and nanocomposites**

PubMed Central

Santra, Santimukul; Kaittanis, Charalambos; Perez, J. Manuel

2009-01-01

Herein we report the design and synthesis of multifunctional hyperbranched polyester-based nanoparticles and nanocomposites with properties ranging from magnetic, fluorescence, antioxidant and X-ray contrast. The fabrication of these nanostructures was achieved using a novel aliphatic and biodegradable hyperbranched polyester (HBPE) synthesized from readily available diethylmalonate. The polymer’s globular structure with functional surface carboxylic groups and hydrophobic cavities residing in the polymer’s interior allows for the formation of multifunctional polymeric nanoparticles, which are able to encapsulate a diversity of hydrophobic cargos. Via simple surface chemistry modifications, the surface carboxylic acid groups were modified to yield nanoparticles with a variety of surface functionalizations, such as amino, azide and propargyl groups, which mediated the conjugation of small molecules. This capability achieved the engineering of the HBPE nanoparticle surface for specific cell internalization studies and the formation of nanoparticle assemblies for the creation of novel nanocomposites that retained, and in some cases enhanced, the properties of the parental nanoparticle building blocks. Considering these results, the HBPE polymer, nanoparticles and composites should be ideal for biomedical, pharmaceutical, nanophotonics and material applications. PMID:19957939

Building blocks for automated elucidation of metabolites: machine learning methods for NMR prediction.

PubMed

Kuhn, Stefan; Egert, Björn; Neumann, Steffen; Steinbeck, Christoph

2008-09-25

Current efforts in Metabolomics, such as the Human Metabolome Project, collect structures of biological metabolites as well as data for their characterisation, such as spectra for identification of substances and measurements of their concentration. Still, only a fraction of existing metabolites and their spectral fingerprints are known. Computer-Assisted Structure Elucidation (CASE) of biological metabolites will be an important tool to leverage this lack of knowledge. Indispensable for CASE are modules to predict spectra for hypothetical structures. This paper evaluates different statistical and machine learning methods to perform predictions of proton NMR spectra based on data from our open database NMRShiftDB. A mean absolute error of 0.18 ppm was achieved for the prediction of proton NMR shifts ranging from 0 to 11 ppm. Random forest, J48 decision tree and support vector machines achieved similar overall errors. HOSE codes being a notably simple method achieved a comparatively good result of 0.17 ppm mean absolute error. NMR prediction methods applied in the course of this work delivered precise predictions which can serve as a building block for Computer-Assisted Structure Elucidation for biological metabolites.

Nanocluster building blocks of artificial square spin ice: Stray-field studies of thermal dynamics

NASA Astrophysics Data System (ADS)

Pohlit, Merlin; Porrati, Fabrizio; Huth, Michael; Ohno, Yuzo; Ohno, Hideo; Müller, Jens

2015-05-01

We present measurements of the thermal dynamics of a Co-based single building block of an artificial square spin ice fabricated by focused electron-beam-induced deposition. We employ micro-Hall magnetometry, an ultra-sensitive tool to study the stray field emanating from magnetic nanostructures, as a new technique to access the dynamical properties during the magnetization reversal of the spin-ice nanocluster. The obtained hysteresis loop exhibits distinct steps, displaying a reduction of their "coercive field" with increasing temperature. Therefore, thermally unstable states could be repetitively prepared by relatively simple temperature and field protocols allowing one to investigate the statistics of their switching behavior within experimentally accessible timescales. For a selected switching event, we find a strong reduction of the so-prepared states' "survival time" with increasing temperature and magnetic field. Besides the possibility to control the lifetime of selected switching events at will, we find evidence for a more complex behavior caused by the special spin ice arrangement of the macrospins, i.e., that the magnetic reversal statistically follows distinct "paths" most likely driven by thermal perturbation.

Controlled Nucleation and Growth of DNA Tile Arrays within Prescribed DNA Origami Frames and Their Dynamics

PubMed Central

2015-01-01

Controlled nucleation of nanoscale building blocks by geometrically defined seeds implanted in DNA nanoscaffolds represents a unique strategy to study and understand the dynamic processes of molecular self-assembly. Here we utilize a two-dimensional DNA origami frame with a hollow interior and selectively positioned DNA hybridization seeds to control the self-assembly of DNA tile building blocks, where the small DNA tiles are directed to fill the interior of the frame through prescribed sticky end interactions. This design facilitates the construction of DNA origami/array hybrids that adopt the overall shape and dimensions of the origami frame, forming a 2D array in the core consisting of a large number of simple repeating DNA tiles. The formation of the origami/array hybrid was characterized with atomic force microscopy, and the nucleation dynamics were monitored by serial AFM scanning and fluorescence spectroscopy, which revealed faster kinetics of growth within the frame as compared to growth without the presence of a frame. Our study provides insight into the fundamental behavior of DNA-based self-assembling systems. PMID:24575893

Scaling up digital circuit computation with DNA strand displacement cascades.

PubMed

Qian, Lulu; Winfree, Erik

2011-06-03

To construct sophisticated biochemical circuits from scratch, one needs to understand how simple the building blocks can be and how robustly such circuits can scale up. Using a simple DNA reaction mechanism based on a reversible strand displacement process, we experimentally demonstrated several digital logic circuits, culminating in a four-bit square-root circuit that comprises 130 DNA strands. These multilayer circuits include thresholding and catalysis within every logical operation to perform digital signal restoration, which enables fast and reliable function in large circuits with roughly constant switching time and linear signal propagation delays. The design naturally incorporates other crucial elements for large-scale circuitry, such as general debugging tools, parallel circuit preparation, and an abstraction hierarchy supported by an automated circuit compiler.

Modular high power diode lasers with flexible 3D multiplexing arrangement optimized for automated manufacturing

NASA Astrophysics Data System (ADS)

Könning, Tobias; Bayer, Andreas; Plappert, Nora; Faßbender, Wilhelm; Dürsch, Sascha; Küster, Matthias; Hubrich, Ralf; Wolf, Paul; Köhler, Bernd; Biesenbach, Jens

2018-02-01

A novel 3-dimensional arrangement of mirrors is used to re-arrange beams from 1-D and 2-D high power diode laser arrays. The approach allows for a variety of stacking geometries, depending on individual requirements. While basic building blocks, including collimating optics, always remain the same, most adaptations can be realized by simple rearrangement of a few optical components. Due to fully automated alignment processes, the required changes can be realized in software by changing coordinates, rather than requiring customized mechanical components. This approach minimizes development costs due to its flexibility, while reducing overall product cost by using similar building blocks for a variety of products and utilizing a high grade of automation. The modules can be operated with industrial grade water, lowering overall system and maintenance cost. Stackable macro coolers are used as the smallest building block of the system. Each cooler can hold up to five diode laser bars. Micro optical components, collimating the beam, are mounted directly to the cooler. All optical assembly steps are fully automated. Initially, the beams from all laser bars propagate in the same direction. Key to the concept is an arrangement of deflectors, which re-arrange the beams into a 2-D array of the desired shape and high fill factor. Standard multiplexing techniques like polarization- or wavelengths-multiplexing have been implemented as well. A variety of fiber coupled modules ranging from a few hundred watts of optical output power to multiple kilowatts of power, as well as customized laser spot geometries like uniform line sources, have been realized.

The Development of Spatial Skills through Interventions Involving Block Building Activities

ERIC Educational Resources Information Center

Casey, Beth M.; Andrews, Nicole; Schindler, Holly; Kersh, Joanne E.; Samper, Alexandra; Copley, Juanita

2008-01-01

This study investigated the use of block-building interventions to develop spatial-reasoning skills in kindergartners. Two intervention conditions and a control condition were included to determine, first, whether the block building activities themselves benefited children's spatial skills, and secondly, whether a story context further improved…

Incorporating GIS building data and census housing statistics for sub-block-level population estimation

USGS Publications Warehouse

Wu, S.-S.; Wang, L.; Qiu, X.

2008-01-01

This article presents a deterministic model for sub-block-level population estimation based on the total building volumes derived from geographic information system (GIS) building data and three census block-level housing statistics. To assess the model, we generated artificial blocks by aggregating census block areas and calculating the respective housing statistics. We then applied the model to estimate populations for sub-artificial-block areas and assessed the estimates with census populations of the areas. Our analyses indicate that the average percent error of population estimation for sub-artificial-block areas is comparable to those for sub-census-block areas of the same size relative to associated blocks. The smaller the sub-block-level areas, the higher the population estimation errors. For example, the average percent error for residential areas is approximately 0.11 percent for 100 percent block areas and 35 percent for 5 percent block areas.

Global Dynamic Exposure and the OpenBuildingMap

NASA Astrophysics Data System (ADS)

Schorlemmer, D.; Beutin, T.; Hirata, N.; Hao, K. X.; Wyss, M.; Cotton, F.; Prehn, K.

2015-12-01

Detailed understanding of local risk factors regarding natural catastrophes requires in-depth characterization of the local exposure. Current exposure capture techniques have to find the balance between resolution and coverage. We aim at bridging this gap by employing a crowd-sourced approach to exposure capturing focusing on risk related to earthquake hazard. OpenStreetMap (OSM), the rich and constantly growing geographical database, is an ideal foundation for us. More than 2.5 billion geographical nodes, more than 150 million building footprints (growing by ~100'000 per day), and a plethora of information about school, hospital, and other critical facility locations allow us to exploit this dataset for risk-related computations. We will harvest this dataset by collecting exposure and vulnerability indicators from explicitly provided data (e.g. hospital locations), implicitly provided data (e.g. building shapes and positions), and semantically derived data, i.e. interpretation applying expert knowledge. With this approach, we can increase the resolution of existing exposure models from fragility classes distribution via block-by-block specifications to building-by-building vulnerability. To increase coverage, we will provide a framework for collecting building data by any person or community. We will implement a double crowd-sourced approach to bring together the interest and enthusiasm of communities with the knowledge of earthquake and engineering experts. The first crowd-sourced approach aims at collecting building properties in a community by local people and activists. This will be supported by tailored building capture tools for mobile devices for simple and fast building property capturing. The second crowd-sourced approach involves local experts in estimating building vulnerability that will provide building classification rules that translate building properties into vulnerability and exposure indicators as defined in the Building Taxonomy 2.0 developed by the Global Earthquake Model (GEM). These indicators will then be combined with a hazard model using the GEM OpenQuake engine to compute a risk model. The free/open framework we will provide can be used on commodity hardware for local to regional exposure capturing and for communities to understand their earthquake risk.

Building Blocks: Enmeshing Technology and Creativity with Artistic Pedagogical Technologies

ERIC Educational Resources Information Center

Janzen, Katherine J.; Perry, Beth; Edwards, Margaret

2017-01-01

Using the analogy of children's building blocks, the reader is guided through the results of a research study that explored the use of three Artistic Pedagogical Technologies (APTs). "Building blocks" was the major theme that emerged from the data. Sub-themes included developing community, enhancing creativity, and risk taking. The…

Top Value Added Chemicals From Biomass: I. Results of Screening for Potential Candidates from Sugars and Synthesis Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Werpy, Todd A.; Holladay, John E.; White, James F.

2004-11-01

This report identifies twelve building block chemicals that can be produced from sugars via biological or chemical conversions. The twelve building blocks can be subsequently converted to a number of high-value bio-based chemicals or materials. Building block chemicals, as considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules. The twelve sugar-based building blocks are 1,4-diacids (succinic, fumaric and malic), 2,5-furan dicarboxylic acid, 3-hydroxy propionic acid, aspartic acid, glucaric acid, glutamic acid, itaconic acid, levulinic acid, 3-hydroxybutyrolactone, glycerol, sorbitol, and xylitol/arabinitol. In addition to building blocks, themore » report outlines the central technical barriers that are preventing the widespread use of biomass for products and chemicals.« less

Style grammars for interactive visualization of architecture.

PubMed

Aliaga, Daniel G; Rosen, Paul A; Bekins, Daniel R

2007-01-01

Interactive visualization of architecture provides a way to quickly visualize existing or novel buildings and structures. Such applications require both fast rendering and an effortless input regimen for creating and changing architecture using high-level editing operations that automatically fill in the necessary details. Procedural modeling and synthesis is a powerful paradigm that yields high data amplification and can be coupled with fast-rendering techniques to quickly generate plausible details of a scene without much or any user interaction. Previously, forward generating procedural methods have been proposed where a procedure is explicitly created to generate particular content. In this paper, we present our work in inverse procedural modeling of buildings and describe how to use an extracted repertoire of building grammars to facilitate the visualization and quick modification of architectural structures and buildings. We demonstrate an interactive application where the user draws simple building blocks and, using our system, can automatically complete the building "in the style of" other buildings using view-dependent texture mapping or nonphotorealistic rendering techniques. Our system supports an arbitrary number of building grammars created from user subdivided building models and captured photographs. Using only edit, copy, and paste metaphors, the entire building styles can be altered and transferred from one building to another in a few operations, enhancing the ability to modify an existing architectural structure or to visualize a novel building in the style of the others.

Technology to Reduce Hypoglycemia

PubMed Central

Yeoh, Ester; Choudhary, Pratik

2015-01-01

Hypoglycemia is a major barrier toward achieving glycemic targets and is associated with significant morbidity (both psychological and physical) and mortality. This article reviews technological strategies, from simple to more advanced technologies, which may help prevent or mitigate exposure to hypoglycemia. More efficient insulin delivery systems, bolus advisor calculators, data downloads providing information on glucose trends, continuous glucose monitoring with alarms warning of hypoglycemia, predictive algorithms, and finally closed loop insulin delivery systems are reviewed. The building blocks to correct use and interpretation of this range of available technology require patient education and appropriate patient selection. PMID:25883167

Gas flow calculation method of a ramjet engine

NASA Astrophysics Data System (ADS)

Kostyushin, Kirill; Kagenov, Anuar; Eremin, Ivan; Zhiltsov, Konstantin; Shuvarikov, Vladimir

2017-11-01

At the present study calculation methodology of gas dynamics equations in ramjet engine is presented. The algorithm is based on Godunov`s scheme. For realization of calculation algorithm, the system of data storage is offered, the system does not depend on mesh topology, and it allows using the computational meshes with arbitrary number of cell faces. The algorithm of building a block-structured grid is given. Calculation algorithm in the software package "FlashFlow" is implemented. Software package is verified on the calculations of simple configurations of air intakes and scramjet models.

Self-organized synthesis of silver dendritic nanostructures via an electroless metal deposition method

NASA Astrophysics Data System (ADS)

Qiu, T.; Wu, X. L.; Mei, Y. F.; Chu, P. K.; Siu, G. G.

2005-09-01

Unique silver dendritic nanostructures, with stems, branches, and leaves, were synthesized with self-organization via a simple electroless metal deposition method in a conventional autoclave containing aqueous HF and AgNO3 solution. Their growth mechanisms are discussed in detail on the basis of a self-assembled localized microscopic electrochemical cell model. A process of diffusion-limited aggregation is suggested for the formation of the silver dendritic nanostructures. This nanostructured material is of great potential to be building blocks for assembling mini-functional devices of the next generation.

Structural Preferential Attachment: Network Organization beyond the Link

NASA Astrophysics Data System (ADS)

Hébert-Dufresne, Laurent; Allard, Antoine; Marceau, Vincent; Noël, Pierre-André; Dubé, Louis J.

2011-10-01

We introduce a mechanism which models the emergence of the universal properties of complex networks, such as scale independence, modularity and self-similarity, and unifies them under a scale-free organization beyond the link. This brings a new perspective on network organization where communities, instead of links, are the fundamental building blocks of complex systems. We show how our simple model can reproduce social and information networks by predicting their community structure and more importantly, how their nodes or communities are interconnected, often in a self-similar manner.

Direct estimations of linear and nonlinear functionals of a quantum state.

PubMed

Ekert, Artur K; Alves, Carolina Moura; Oi, Daniel K L; Horodecki, Michał; Horodecki, Paweł; Kwek, L C

2002-05-27

We present a simple quantum network, based on the controlled-SWAP gate, that can extract certain properties of quantum states without recourse to quantum tomography. It can be used as a basic building block for direct quantum estimations of both linear and nonlinear functionals of any density operator. The network has many potential applications ranging from purity tests and eigenvalue estimations to direct characterization of some properties of quantum channels. Experimental realizations of the proposed network are within the reach of quantum technology that is currently being developed.

Intercultural Communication Activities in the Classroom: Turning Stumbling Blocks into Building Blocks.

ERIC Educational Resources Information Center

Dillon, Randy K.

This paper explores behavior patterns that inhibit effective communication in everyday, educational, and business cross-cultural settings. Opportunities to change these inhibiting patterns, metaphorically referred to as "stumbling blocks," into building blocks or tools for successful intercultural understandings are discussed in the…

Interlocking Toy Building Blocks as Hands-On Learning Modules for Blind and Visually Impaired Chemistry Students

ERIC Educational Resources Information Center

Melaku, Samuel; Schreck, James O.; Griffin, Kameron; Dabke, Rajeev B.

2016-01-01

Interlocking toy building blocks (e.g., Lego) as chemistry learning modules for blind and visually impaired (BVI) students in high school and undergraduate introductory or general chemistry courses are presented. Building blocks were assembled on a baseplate to depict the relative changes in the periodic properties of elements. Modules depicting…

The impact of domestic rainwater harvesting systems in storm water runoff mitigation at the urban block scale.

PubMed

Palla, A; Gnecco, I; La Barbera, P

2017-04-15

In the framework of storm water management, Domestic Rainwater Harvesting (DRWH) systems are recently recognized as source control solutions according to LID principles. In order to assess the impact of these systems in storm water runoff control, a simple methodological approach is proposed. The hydrologic-hydraulic modelling is undertaken using EPA SWMM; the DRWH is implemented in the model by using a storage unit linked to the building water supply system and to the drainage network. The proposed methodology has been implemented for a residential urban block located in Genoa (Italy). Continuous simulations are performed by using the high-resolution rainfall data series for the ''do nothing'' and DRWH scenarios. The latter includes the installation of a DRWH system for each building of the urban block. Referring to the test site, the peak and volume reduction rate evaluated for the 2125 rainfall events are respectively equal to 33 and 26 percent, on average (with maximum values of 65 percent for peak and 51 percent for volume). In general, the adopted methodology indicates that the hydrologic performance of the storm water drainage network equipped with DRWH systems is noticeable even for the design storm event (T = 10 years) and the rainfall depth seems to affect the hydrologic performance at least when the total depth exceeds 20 mm. Copyright © 2017 Elsevier Ltd. All rights reserved.

Building Curriculum during Block Play

ERIC Educational Resources Information Center

Andrews, Nicole

2015-01-01

Blocks are not just for play! In this article, Nicole Andrews describes observing the interactions of three young boys enthusiastically engaged in the kindergarten block center of their classroom, using blocks in a building project that displayed their ability to use critical thinking skills, physics exploration, and the development of language…

Flexible and Stretchable Energy Storage: Recent Advances and Future Perspectives.

PubMed

Liu, Wei; Song, Min-Sang; Kong, Biao; Cui, Yi

2017-01-01

Energy-storage technologies such as lithium-ion batteries and supercapacitors have become fundamental building blocks in modern society. Recently, the emerging direction toward the ever-growing market of flexible and wearable electronics has nourished progress in building multifunctional energy-storage systems that can be bent, folded, crumpled, and stretched while maintaining their electrochemical functions under deformation. Here, recent progress and well-developed strategies in research designed to accomplish flexible and stretchable lithium-ion batteries and supercapacitors are reviewed. The challenges of developing novel materials and configurations with tailored features, and in designing simple and large-scaled manufacturing methods that can be widely utilized are considered. Furthermore, the perspectives and opportunities for this emerging field of materials science and engineering are also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Multimodular biocatalysts for natural product assembly

NASA Astrophysics Data System (ADS)

Schwarzer, Dirk; Marahiel, Mohamed A.

2001-03-01

Nonribosomal peptides and polyketides represent a large class of natural products that show an extreme structural diversity and broad pharmacological relevance. They are synthesized from simple building blocks such as amino or carboxy acids and malonate derivatives on multimodular enzymes called nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs), respectively. Although utilizing different substrates, NRPSs and PKSs show striking similarities in the modular architecture of their catalytic domains and product assembly-line mechanism. Among these compounds are well known antibiotics (penicillin, vancomycin and erythromycin) as well as potent immunosuppressive agents (cyclosporin, rapamycin and FK 506). This review focuses on the modular organization of NRPSs, PKSs and mixed NRPS/PKS systems and how modules and domains that build up the biosynthetic templates can be exploited for the rational design of recombinant enzymes capable of synthesizing novel compounds.

The 10 Building Blocks of High-Performing Primary Care

PubMed Central

Bodenheimer, Thomas; Ghorob, Amireh; Willard-Grace, Rachel; Grumbach, Kevin

2014-01-01

Our experiences studying exemplar primary care practices, and our work assisting other practices to become more patient centered, led to a formulation of the essential elements of primary care, which we call the 10 building blocks of high-performing primary care. The building blocks include 4 foundational elements—engaged leadership, data-driven improvement, empanelment, and team-based care—that assist the implementation of the other 6 building blocks—patient-team partnership, population management, continuity of care, prompt access to care, comprehensiveness and care coordination, and a template of the future. The building blocks, which represent a synthesis of the innovative thinking that is transforming primary care in the United States, are both a description of existing high-performing practices and a model for improvement. PMID:24615313

Simple arithmetic: not so simple for highly math anxious individuals.

PubMed

Chang, Hyesang; Sprute, Lisa; Maloney, Erin A; Beilock, Sian L; Berman, Marc G

2017-12-01

Fluency with simple arithmetic, typically achieved in early elementary school, is thought to be one of the building blocks of mathematical competence. Behavioral studies with adults indicate that math anxiety (feelings of tension or apprehension about math) is associated with poor performance on cognitively demanding math problems. However, it remains unclear whether there are fundamental differences in how high and low math anxious individuals approach overlearned simple arithmetic problems that are less reliant on cognitive control. The current study used functional magnetic resonance imaging to examine the neural correlates of simple arithmetic performance across high and low math anxious individuals. We implemented a partial least squares analysis, a data-driven, multivariate analysis method to measure distributed patterns of whole-brain activity associated with performance. Despite overall high simple arithmetic performance across high and low math anxious individuals, performance was differentially dependent on the fronto-parietal attentional network as a function of math anxiety. Specifically, low-compared to high-math anxious individuals perform better when they activate this network less-a potential indication of more automatic problem-solving. These findings suggest that low and high math anxious individuals approach even the most fundamental math problems differently. © The Author (2017). Published by Oxford University Press.

Simple arithmetic: not so simple for highly math anxious individuals

PubMed Central

Sprute, Lisa; Maloney, Erin A; Beilock, Sian L; Berman, Marc G

2017-01-01

Abstract Fluency with simple arithmetic, typically achieved in early elementary school, is thought to be one of the building blocks of mathematical competence. Behavioral studies with adults indicate that math anxiety (feelings of tension or apprehension about math) is associated with poor performance on cognitively demanding math problems. However, it remains unclear whether there are fundamental differences in how high and low math anxious individuals approach overlearned simple arithmetic problems that are less reliant on cognitive control. The current study used functional magnetic resonance imaging to examine the neural correlates of simple arithmetic performance across high and low math anxious individuals. We implemented a partial least squares analysis, a data-driven, multivariate analysis method to measure distributed patterns of whole-brain activity associated with performance. Despite overall high simple arithmetic performance across high and low math anxious individuals, performance was differentially dependent on the fronto-parietal attentional network as a function of math anxiety. Specifically, low—compared to high—math anxious individuals perform better when they activate this network less—a potential indication of more automatic problem-solving. These findings suggest that low and high math anxious individuals approach even the most fundamental math problems differently. PMID:29140499

Characteristics of Recycled Concrete Aggregates from Precast Slab Block Buildings

NASA Astrophysics Data System (ADS)

Venkrbec, Václav; Nováková, Iveta; Henková, Svatava

2017-10-01

Precast slab block buildings (PSBB) typically and frequently occur in Central and Eastern Europe, as well as elsewhere in the world. Some of these buildings are currently used beyond their service life capacity. The utilization of recycled materials from these buildings with regard to applying the principles of sustainable construction and using recycled materials will probably be significant in the following years. Documentation from the manufacturing processes of prefabricated blocks for precast slab block buildings is not available, and also it is difficult to declare technological discipline during the construction of these buildings. Therefore, properties of recycled concrete aggregates (RCA) produced from construction and demolition waste (C&DW) of precast slab block buildings build between 1950s to 1990s are not sufficiently known. The demolition of these buildings is very rare today, but it can be assumed an increase in demolitions of these buildings in the future. The use of RCA in new concrete requires verification/testing of the geometrical and physical properties of RCA according to the EN 12 620+A1 standard. The aim of the contribution is to present a case study of the demolition of slab block building with emphasis on RCA usage. The paper presents the results of the tests according to European standards for determining selected geometrical and physical properties of the RCA. The paper describes and evaluates tests such as determination of particle size distribution - Sieve Analysis, content of fine particles, determination of density and water absorption. The results of the properties testing of RCA are compared with the properties of natural aggregate. The general boundary conditions of RCA particular tests are presented.

Rational design of alpha-helical tandem repeat proteins with closed architectures

PubMed Central

Doyle, Lindsey; Hallinan, Jazmine; Bolduc, Jill; Parmeggiani, Fabio; Baker, David; Stoddard, Barry L.; Bradley, Philip

2015-01-01

Tandem repeat proteins, which are formed by repetition of modular units of protein sequence and structure, play important biological roles as macromolecular binding and scaffolding domains, enzymes, and building blocks for the assembly of fibrous materials1,2. The modular nature of repeat proteins enables the rapid construction and diversification of extended binding surfaces by duplication and recombination of simple building blocks3,4. The overall architecture of tandem repeat protein structures – which is dictated by the internal geometry and local packing of the repeat building blocks – is highly diverse, ranging from extended, super-helical folds that bind peptide, DNA, and RNA partners5–9, to closed and compact conformations with internal cavities suitable for small molecule binding and catalysis10. Here we report the development and validation of computational methods for de novo design of tandem repeat protein architectures driven purely by geometric criteria defining the inter-repeat geometry, without reference to the sequences and structures of existing repeat protein families. We have applied these methods to design a series of closed alpha-solenoid11 repeat structures (alpha-toroids) in which the inter-repeat packing geometry is constrained so as to juxtapose the N- and C-termini; several of these designed structures have been validated by X-ray crystallography. Unlike previous approaches to tandem repeat protein engineering12–20, our design procedure does not rely on template sequence or structural information taken from natural repeat proteins and hence can produce structures unlike those seen in nature. As an example, we have successfully designed and validated closed alpha-solenoid repeats with a left-handed helical architecture that – to our knowledge – is not yet present in the protein structure database21. PMID:26675735

Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies.

PubMed

Vogel, Nicolas; Utech, Stefanie; England, Grant T; Shirman, Tanya; Phillips, Katherine R; Koay, Natalie; Burgess, Ian B; Kolle, Mathias; Weitz, David A; Aizenberg, Joanna

2015-09-01

Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal's curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies--potentially as more efficient mimics of structural color as it occurs in nature.

Color from hierarchy: Diverse optical properties of micron-sized spherical colloidal assemblies

PubMed Central

Vogel, Nicolas; Utech, Stefanie; England, Grant T.; Shirman, Tanya; Phillips, Katherine R.; Koay, Natalie; Burgess, Ian B.; Kolle, Mathias; Weitz, David A.; Aizenberg, Joanna

2015-01-01

Materials in nature are characterized by structural order over multiple length scales have evolved for maximum performance and multifunctionality, and are often produced by self-assembly processes. A striking example of this design principle is structural coloration, where interference, diffraction, and absorption effects result in vivid colors. Mimicking this emergence of complex effects from simple building blocks is a key challenge for man-made materials. Here, we show that a simple confined self-assembly process leads to a complex hierarchical geometry that displays a variety of optical effects. Colloidal crystallization in an emulsion droplet creates micron-sized superstructures, termed photonic balls. The curvature imposed by the emulsion droplet leads to frustrated crystallization. We observe spherical colloidal crystals with ordered, crystalline layers and a disordered core. This geometry produces multiple optical effects. The ordered layers give rise to structural color from Bragg diffraction with limited angular dependence and unusual transmission due to the curved nature of the individual crystals. The disordered core contributes nonresonant scattering that induces a macroscopically whitish appearance, which we mitigate by incorporating absorbing gold nanoparticles that suppress scattering and macroscopically purify the color. With increasing size of the constituent colloidal particles, grating diffraction effects dominate, which result from order along the crystal’s curved surface and induce a vivid polychromatic appearance. The control of multiple optical effects induced by the hierarchical morphology in photonic balls paves the way to use them as building blocks for complex optical assemblies—potentially as more efficient mimics of structural color as it occurs in nature. PMID:26290583

INFERENCE BUILDING BLOCKS

DTIC Science & Technology

2018-02-15

address the problem that probabilistic inference algorithms are diÿcult and tedious to implement, by expressing them in terms of a small number of...building blocks, which are automatic transformations on probabilistic programs. On one hand, our curation of these building blocks reflects the way human...reasoning with low-level computational optimization, so the speed and accuracy of the generated solvers are competitive with state-of-the-art systems. 15

1. John C. Garner, Jr., Photographer 1967 PRINCIPAL (NORTH) SIDE, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. John C. Garner, Jr., Photographer 1967 PRINCIPAL (NORTH) SIDE, FROM NORTHWEST. THE RIGHT END OF THE BLOCK IS THE E.S. WOOD BUILDING; THE BUILDING WITH A FIRE ESCAPE IS THE ROSENFIELD BUILDING; THE T.W. HOUSE BUILDING IS TO THE LEFT OF THE PRECEDING BUILDING; JOHN BERLOCHER BUILDING IS AT THE LEFT END OF THE BLOCK. - Strand Historic District, Wood-Rosenfield-House-Berlocher Buildings, 2213-2223 Strand, Galveston, Galveston County, TX

Programmable and Shape-Memorizing Information Carriers.

PubMed

Li, Wenbing; Liu, Yanju; Leng, Jinsong

2017-12-27

Shape memory polymers (SMPs) are expected to play more and more important roles in space-deployable structures, smart actuators, and other high-tech areas. Nevertheless, because of the difficulties in fabrication and the programmability of temporary shape recovery, SMPs have not yet been widely applied in real fields. It is ideal to incorporate the different independent functional building blocks into a material. Herein, we designed a simple method to incorporate four functional building blocks: a neat epoxy-based shape memory (neat SMEP) resin, an SMEP composited with Fe 3 O 4 (SMEP-Fe 3 O 4 ), an SMEP composited with multiwalled carbon nanotubes, and an SMEP composited with p-aminodiphenylimide into a multicomposite, in which the four region surfaces could be programmed with different language code patterns according to a preset command by imprint lithography. Then, we aimed to reprogram the initially raised code patterns into temporary flat patterns using programming mold that, when triggered by a preset stimulus process such as an alternating magnetic field, radiofrequency field, 365 nm UV, and direct heating, could transform these language codes into the information passed by the customer. The concept introduced here will be applied to other available SMPs and provide a practical method to realize the information delivery.

Combinatorics of aliphatic amino acids

NASA Astrophysics Data System (ADS)

Grützmann, Konrad; Böcker, Sebastian; Schuster, Stefan

2011-01-01

This study combines biology and mathematics, showing that a relatively simple question from molecular biology can lead to complicated mathematics. The question is how to calculate the number of theoretically possible aliphatic amino acids as a function of the number of carbon atoms in the side chain. The presented calculation is based on earlier results from theoretical chemistry concerning alkyl compounds. Mathematical properties of this number series are highlighted. We discuss which of the theoretically possible structures really occur in living organisms, such as leucine and isoleucine with a chain length of four. This is done both for a strict definition of aliphatic amino acids only involving carbon and hydrogen atoms in their side chain and for a less strict definition allowing sulphur, nitrogen and oxygen atoms. While the main focus is on proteinogenic amino acids, we also give several examples of non-proteinogenic aliphatic amino acids, playing a role, for instance, in signalling. The results are in agreement with a general phenomenon found in biology: Usually, only a small number of molecules are chosen as building blocks to assemble an inconceivable number of different macromolecules as proteins. Thus, natural biological complexity arises from the multifarious combination of building blocks.

High-power VCSEL systems and applications

NASA Astrophysics Data System (ADS)

Moench, Holger; Conrads, Ralf; Deppe, Carsten; Derra, Guenther; Gronenborn, Stephan; Gu, Xi; Heusler, Gero; Kolb, Johanna; Miller, Michael; Pekarski, Pavel; Pollmann-Retsch, Jens; Pruijmboom, Armand; Weichmann, Ulrich

2015-03-01

Easy system design, compactness and a uniform power distribution define the basic advantages of high power VCSEL systems. Full addressability in space and time add new dimensions for optimization and enable "digital photonic production". Many thermal processes benefit from the improved control i.e. heat is applied exactly where and when it is needed. The compact VCSEL systems can be integrated into most manufacturing equipment, replacing batch processes using large furnaces and reducing energy consumption. This paper will present how recent technological development of high power VCSEL systems will extend efficiency and flexibility of thermal processes and replace not only laser systems, lamps and furnaces but enable new ways of production. High power VCSEL systems are made from many VCSEL chips, each comprising thousands of low power VCSELs. Systems scalable in power from watts to multiple ten kilowatts and with various form factors utilize a common modular building block concept. Designs for reliable high power VCSEL arrays and systems can be developed and tested on each building block level and benefit from the low power density and excellent reliability of the VCSELs. Furthermore advanced assembly concepts aim to reduce the number of individual processes and components and make the whole system even more simple and reliable.

New Modular Ultrasonic Signal Processing Building Blocks for Real-Time Data Acquisition and Post Processing

NASA Astrophysics Data System (ADS)

Weber, Walter H.; Mair, H. Douglas; Jansen, Dion

2003-03-01

A suite of basic signal processors has been developed. These basic building blocks can be cascaded together to form more complex processors without the need for programming. The data structures between each of the processors are handled automatically. This allows a processor built for one purpose to be applied to any type of data such as images, waveform arrays and single values. The processors are part of Winspect Data Acquisition software. The new processors are fast enough to work on A-scan signals live while scanning. Their primary use is to extract features, reduce noise or to calculate material properties. The cascaded processors work equally well on live A-scan displays, live gated data or as a post-processing engine on saved data. Researchers are able to call their own MATLAB or C-code from anywhere within the processor structure. A built-in formula node processor that uses a simple algebraic editor may make external user programs unnecessary. This paper also discusses the problems associated with ad hoc software development and how graphical programming languages can tie up researchers writing software rather than designing experiments.

Nanocluster building blocks of artificial square spin ice: Stray-field studies of thermal dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pohlit, Merlin, E-mail: pohlit@physik.uni-frankfurt.de; Porrati, Fabrizio; Huth, Michael

We present measurements of the thermal dynamics of a Co-based single building block of an artificial square spin ice fabricated by focused electron-beam-induced deposition. We employ micro-Hall magnetometry, an ultra-sensitive tool to study the stray field emanating from magnetic nanostructures, as a new technique to access the dynamical properties during the magnetization reversal of the spin-ice nanocluster. The obtained hysteresis loop exhibits distinct steps, displaying a reduction of their “coercive field” with increasing temperature. Therefore, thermally unstable states could be repetitively prepared by relatively simple temperature and field protocols allowing one to investigate the statistics of their switching behavior withinmore » experimentally accessible timescales. For a selected switching event, we find a strong reduction of the so-prepared states' “survival time” with increasing temperature and magnetic field. Besides the possibility to control the lifetime of selected switching events at will, we find evidence for a more complex behavior caused by the special spin ice arrangement of the macrospins, i.e., that the magnetic reversal statistically follows distinct “paths” most likely driven by thermal perturbation.« less

A Library of Rad Hard Mixed-Voltage/Mixed-Signal Building Blocks for Integration of Avionics Systems for Deep Space

NASA Technical Reports Server (NTRS)

Mojarradi, M. M.; Blaes, B.; Kolawa, E. A.; Blalock, B. J.; Li, H. W.; Buck, K.; Houge, D.

2001-01-01

To build the sensor intensive system-on-a-chip for the next generation spacecrafts for deep space, Center for Integration of Space Microsystems at JPL (CISM) takes advantage of the lower power rating and inherent radiation resistance of Silicon on Insulator technology (SOI). We are developing a suite of mixed-voltage and mixed-signal building blocks in Honeywell's SOI process that can enable the rapid integration of the next generation avionics systems with lower power rating, higher reliability, longer life, and enhanced radiation tolerance for spacecrafts such as the Europa Orbiter and Europa Lander. The mixed-voltage building blocks are predominantly for design of adaptive power management systems. Their design centers around an LDMOS structure that is being developed by Honeywell, Boeing Corp, and the University of Idaho. The mixed-signal building blocks are designed to meet the low power, extreme radiation requirement of deep space applications. These building blocks are predominantly used to interface analog sensors to the digital CPU of the next generation avionics system on a chip. Additional information is contained in the original extended abstract.

Solvent mediated hybrid 2D materials: black phosphorus - graphene heterostructured building blocks assembled for sodium ion batteries.

PubMed

Li, Mengya; Muralidharan, Nitin; Moyer, Kathleen; Pint, Cary L

2018-06-07

Here we demonstrate the broad capability to exploit interactions at different length scales in 2D materials to prepare macroscopic functional materials containing hybrid black phosphorus/graphene (BP/G) heterostructured building blocks. First, heterostructured 2D building blocks are self-assembled during co-exfoliation in the solution phase based on electrostatic attraction of different 2D materials. Second, electrophoretic deposition is used as a tool to assemble these building blocks into macroscopic films containing these self-assembled 2D heterostructures. Characterization of deposits formed using this technique elucidates the presence of stacked and sandwiched 2D heterostructures, and zeta potential measurements confirm the mechanistic interactions driving this assembly. Building on the exceptional sodium alloying capacity of BP, these materials were demonstrated as superior binder-free and additive-free anodes for sodium batteries with specific discharge capacity of 2365 mA h gP-1 and long stable cycling duration. This study demonstrates how controllable co-processing of 2D materials can enable material control for stacking and building block assembly relevant to broad future applications of 2D materials.

Top Value Added Chemicals from Biomass - Volume I, Results of Screening for Potential Candidates from Sugars and Synthesis Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2004-08-01

This report identifies twelve building block chemicals that can be produced from sugars via biological or chemical conversions. The twelve building blocks can be subsequently converted to a number of high-value bio-based chemicals or materials. Building block chemicals, as considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules. The twelve sugar-based building blocks are 1,4-diacids (succinic, fumaric and malic), 2,5-furan dicarboxylic acid, 3-hydroxy propionic acid, aspartic acid, glucaric acid, glutamic acid, itaconic acid, levulinic acid, 3-hydroxybutyrolactone, glycerol, sorbitol, and xylitol/arabinitol.

Top Value Added Chemicals from Biomass: Volume I -- Results of Screening for Potential Candidates from Sugars and Synthesis Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Werpy, T.; Petersen, G.

2004-08-01

This report identifies twelve building block chemicals that can be produced from sugars via biological or chemical conversions. The twelve building blocks can be subsequently converted to a number of high-value bio-based chemicals or materials. Building block chemicals, as considered for this analysis, are molecules with multiple functional groups that possess the potential to be transformed into new families of useful molecules. The twelve sugar-based building blocks are 1,4-diacids (succinic, fumaric and malic), 2,5-furan dicarboxylic acid, 3-hydroxy propionic acid, aspartic acid, glucaric acid, glutamic acid, itaconic acid, levulinic acid, 3-hydroxybutyrolactone, glycerol, sorbitol, and xylitol/arabinitol.

Computational strategies for the automated design of RNA nanoscale structures from building blocks using NanoTiler.

PubMed

Bindewald, Eckart; Grunewald, Calvin; Boyle, Brett; O'Connor, Mary; Shapiro, Bruce A

2008-10-01

One approach to designing RNA nanoscale structures is to use known RNA structural motifs such as junctions, kissing loops or bulges and to construct a molecular model by connecting these building blocks with helical struts. We previously developed an algorithm for detecting internal loops, junctions and kissing loops in RNA structures. Here we present algorithms for automating or assisting many of the steps that are involved in creating RNA structures from building blocks: (1) assembling building blocks into nanostructures using either a combinatorial search or constraint satisfaction; (2) optimizing RNA 3D ring structures to improve ring closure; (3) sequence optimisation; (4) creating a unique non-degenerate RNA topology descriptor. This effectively creates a computational pipeline for generating molecular models of RNA nanostructures and more specifically RNA ring structures with optimized sequences from RNA building blocks. We show several examples of how the algorithms can be utilized to generate RNA tecto-shapes.

Computational strategies for the automated design of RNA nanoscale structures from building blocks using NanoTiler☆

PubMed Central

Bindewald, Eckart; Grunewald, Calvin; Boyle, Brett; O’Connor, Mary; Shapiro, Bruce A.

2013-01-01

One approach to designing RNA nanoscale structures is to use known RNA structural motifs such as junctions, kissing loops or bulges and to construct a molecular model by connecting these building blocks with helical struts. We previously developed an algorithm for detecting internal loops, junctions and kissing loops in RNA structures. Here we present algorithms for automating or assisting many of the steps that are involved in creating RNA structures from building blocks: (1) assembling building blocks into nanostructures using either a combinatorial search or constraint satisfaction; (2) optimizing RNA 3D ring structures to improve ring closure; (3) sequence optimisation; (4) creating a unique non-degenerate RNA topology descriptor. This effectively creates a computational pipeline for generating molecular models of RNA nanostructures and more specifically RNA ring structures with optimized sequences from RNA building blocks. We show several examples of how the algorithms can be utilized to generate RNA tecto-shapes. PMID:18838281

Synthesis of most polyene natural product motifs using just twelve building blocks and one coupling reaction

PubMed Central

Woerly, Eric M.; Roy, Jahnabi; Burke, Martin D.

2014-01-01

The inherent modularity of polypeptides, oligonucleotides, and oligosaccharides has been harnessed to achieve generalized building block-based synthesis platforms. Importantly, like these other targets, most small molecule natural products are biosynthesized via iterative coupling of bifunctional building blocks. This suggests that many small molecules also possess inherent modularity commensurate with systematic building block-based construction. Supporting this hypothesis, here we report that the polyene motifs found in >75% of all known polyene natural products can be synthesized using just 12 building blocks and one coupling reaction. Using the same general retrosynthetic algorithm and reaction conditions, this platform enabled the synthesis of a wide range of polyene frameworks covering all of this natural product chemical space, and first total syntheses of the polyene natural products asnipyrone B, physarigin A, and neurosporaxanthin β-D-glucopyranoside. Collectively, these results suggest the potential for a more generalized approach for making small molecules in the laboratory. PMID:24848233

COMPRESSOR BUILDING, TRA626. ELEVATIONS. WINDOWS. WALL SECTIONS. PUMICE BLOCK BUILDING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

COMPRESSOR BUILDING, TRA-626. ELEVATIONS. WINDOWS. WALL SECTIONS. PUMICE BLOCK BUILDING HOUSED COMPRESSORS FOR AIRCRAFT NUCLEAR PROPULSION EXPERIMENTS. MTR-626-IDO-2S, 3/1952. INL INDEX NO. 531-0626-00-396-110535, REV. 2. - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Modular arrangement of regulatory RNA elements.

PubMed

Roßmanith, Johanna; Narberhaus, Franz

2017-03-04

Due to their simple architecture and control mechanism, regulatory RNA modules are attractive building blocks in synthetic biology. This is especially true for riboswitches, which are natural ligand-binding regulators of gene expression. The discovery of various tandem riboswitches inspired the design of combined RNA modules with activities not yet found in nature. Riboswitches were placed in tandem or in combination with a ribozyme or temperature-responsive RNA thermometer resulting in new functionalities. Here, we compare natural examples of tandem riboswitches with recently designed artificial RNA regulators suggesting substantial modularity of regulatory RNA elements. Challenges associated with modular RNA design are discussed.

Technology to Reduce Hypoglycemia.

PubMed

Yeoh, Ester; Choudhary, Pratik

2015-07-01

Hypoglycemia is a major barrier toward achieving glycemic targets and is associated with significant morbidity (both psychological and physical) and mortality. This article reviews technological strategies, from simple to more advanced technologies, which may help prevent or mitigate exposure to hypoglycemia. More efficient insulin delivery systems, bolus advisor calculators, data downloads providing information on glucose trends, continuous glucose monitoring with alarms warning of hypoglycemia, predictive algorithms, and finally closed loop insulin delivery systems are reviewed. The building blocks to correct use and interpretation of this range of available technology require patient education and appropriate patient selection. © 2015 Diabetes Technology Society.

Emerging biomedical applications of synthetic biology.

PubMed

Weber, Wilfried; Fussenegger, Martin

2011-11-29

Synthetic biology aims to create functional devices, systems and organisms with novel and useful functions on the basis of catalogued and standardized biological building blocks. Although they were initially constructed to elucidate the dynamics of simple processes, designed devices now contribute to the understanding of disease mechanisms, provide novel diagnostic tools, enable economic production of therapeutics and allow the design of novel strategies for the treatment of cancer, immune diseases and metabolic disorders, such as diabetes and gout, as well as a range of infectious diseases. In this Review, we cover the impact and potential of synthetic biology for biomedical applications.

Hydrogen isotope exchange in a metal hydride tube

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, David B.

2014-09-01

This report describes a model of the displacement of one hydrogen isotope within a metal hydride tube by a different isotope in the gas phase that is blown through the tube. The model incorporates only the most basic parameters to make a clear connection to the theory of open-tube gas chromatography, and to provide a simple description of how the behavior of the system scales with controllable parameters such as gas velocity and tube radius. A single tube can be seen as a building block for more complex architectures that provide higher molar flow rates or other advanced design goals.

Water-soluble cationic conjugated polymers: response to electron-rich bioanalytes.

PubMed

Rochat, Sébastien; Swager, Timothy M

2013-11-27

We report the concise synthesis of a symmetrical monomer that provides a head-to-head pyridine building block for the preparation of cationic conjugated polymers. The obtained poly(pyridinium-phenylene) polymers display appealing properties such as high electron affinity, charge-transport upon n-doping, and optical response to electron-donating analytes. A simple assay for the optical detection of low micromolar amounts of a variety of analytes in aqueous solution was developed. In particular, caffeine could be measured at a 25 μM detection limit. The reported polymers are also suitable for layer-by-layer film formation.

Redox Catalysis Facilitates Lignin Depolymerization

PubMed Central

2017-01-01

Lignin is a recalcitrant and underexploited natural feedstock for aromatic commodity chemicals, and its degradation generally requires the use of high temperatures and harsh reaction conditions. Herein we present an ambient temperature one-pot process for the controlled oxidation and depolymerization of this potent resource. Harnessing the potential of electrocatalytic oxidation in conjugation with our photocatalytic cleavage methodology, we have developed an operationally simple procedure for selective fragmentation of β-O-4 bonds with excellent mass recovery, which provides a unique opportunity to expand the existing lignin usage from energy source to commodity chemicals and synthetic building block source. PMID:28691074

A route to oligosaccharide-appended salicylaldehydes: useful building blocks for the synthesis of metal-salophen complexes.

PubMed

Bedini, Emiliano; Forte, Gianpiero; De Castro, Cristina; Parrilli, Michelangelo; Dalla Cort, Antonella

2013-08-16

A simple and general synthetic protocol to obtain oligosaccharide-appended salicylaldehydes, key intermediates for the synthesis of water-soluble metal-salophen complexes, is here reported. Six new aldehydes have been prepared and fully characterized as well as the corresponding zinc- and uranyl-salophen complexes. These new derivatives show very good solubility in water. Preliminary studies on the association of compound 19-U, that is, the uranyl maltotetraose derivative, with hydrogen phosphate and fluoride provide very encouraging results and open up the possibility of using such compounds for the efficient recognition of anions in pure water.

Bottom-up construction of a superstructure in a porous uranium-organic crystal

NASA Astrophysics Data System (ADS)

Li, Peng; Vermeulen, Nicolaas A.; Malliakas, Christos D.; Gómez-Gualdrón, Diego A.; Howarth, Ashlee J.; Mehdi, B. Layla; Dohnalkova, Alice; Browning, Nigel D.; O'Keeffe, Michael; Farha, Omar K.

2017-05-01

Bottom-up construction of highly intricate structures from simple building blocks remains one of the most difficult challenges in chemistry. We report a structurally complex, mesoporous uranium-based metal-organic framework (MOF) made from simple starting components. The structure comprises 10 uranium nodes and seven tricarboxylate ligands (both crystallographically nonequivalent), resulting in a 173.3-angstrom cubic unit cell enclosing 816 uranium nodes and 816 organic linkers—the largest unit cell found to date for any nonbiological material. The cuboctahedra organize into pentagonal and hexagonal prismatic secondary structures, which then form tetrahedral and diamond quaternary topologies with unprecedented complexity. This packing results in the formation of colossal icosidodecahedral and rectified hexakaidecahedral cavities with internal diameters of 5.0 nanometers and 6.2 nanometers, respectively—ultimately giving rise to the lowest-density MOF reported to date.

Direct N-alkylation of unprotected amino acids with alcohols

PubMed Central

Yan, Tao; Feringa, Ben L.; Barta, Katalin

2017-01-01

N-alkyl amino acids find widespread application as highly valuable, renewable building blocks. However, traditional synthesis methodologies to obtain these suffer from serious limitations, providing a major challenge to develop sustainable alternatives. We report the first powerful catalytic strategy for the direct N-alkylation of unprotected α-amino acids with alcohols. This method is highly selective, produces water as the only side product leading to a simple purification procedure, and a variety of α-amino acids are mono- or di-N-alkylated, in most cases with excellent retention of optical purity. The hydrophobicity of the products is tunable, and even simple peptides are selectively alkylated. An iron-catalyzed route to mono-N-alkyl amino acids using renewable fatty alcohols is also described that represents an ideal green transformation for obtaining fully bio-based surfactants. PMID:29226249

Nanoarchitectonics

NASA Astrophysics Data System (ADS)

Ariga, Katsuhiko; Aono, Masakazu

2016-11-01

The construction of functional systems with nanosized parts would not possible by simple technology (nanotechnology). It can be handled by certain kinds of more sophisticated carpenter work or artistic architectonics (nanoarchitectonics). However, architecting materials in the nanoscale is not very simple because of various unexpected and uncontrollable thermal/statistical fluctuations and mutual interactions. The latter factors inevitably disturb the interactions between component building blocks. Therefore, several techniques and actions, including the regulation of atomic/molecular manipulation, molecular modification by organic chemistry, control of physicochemical interactions, self-assembly/organization, and application of external physical stimuli, must be well combined. This short review describes the historical backgrounds and essences of nanoarchitectonics, followed by a brief introduction of recent examples related to nanoarchitectonics. These examples are categorized in accordance with their physical usages: (i) atom/molecule control; (ii) devices and sensors; (iii) the other applications based on interfacial nanoarchitectonics.

Encapsulation of an interpenetrated diamondoid inorganic building block in a metal-organic framework.

PubMed

Zhang, Huabin; Lin, Ping; Chen, Erxia; Tan, Yanxi; Wen, Tian; Aldalbahi, Ali; Alshehri, Saad M; Yamauchi, Yusuke; Du, Shaowu; Zhang, Jian

2015-03-23

The first example of an inorganic-organic composite framework with an interpenetrated diamondoid inorganic building block, featuring unique {InNa}n helices and {In12 Na16 } nano-rings, has been constructed and structurally characterized. This framework also represents a unique example of encapsulation of an interpenetrated diamondoid inorganic building block in a metal-organic framework. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

23. The Stroud Building beard the 'Temme Springs' advertisement. Westfacing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

23. The Stroud Building beard the 'Temme Springs' advertisement. West-facing windows of the entire block are protected from the afternoon sun by awnings. The north-facing windows of the second-story restaurant were later blocked by an adjacent two-story building. Circa 1914. Credit PPL. - Stroud Building, 31-33 North Central Avenue, Phoenix, Maricopa County, AZ

Polymer-based platform for microfluidic systems

DOEpatents

Benett, William [Livermore, CA; Krulevitch, Peter [Pleasanton, CA; Maghribi, Mariam [Livermore, CA; Hamilton, Julie [Tracy, CA; Rose, Klint [Boston, MA; Wang, Amy W [Oakland, CA

2009-10-13

A method of forming a polymer-based microfluidic system platform using network building blocks selected from a set of interconnectable network building blocks, such as wire, pins, blocks, and interconnects. The selected building blocks are interconnectably assembled and fixedly positioned in precise positions in a mold cavity of a mold frame to construct a three-dimensional model construction of a microfluidic flow path network preferably having meso-scale dimensions. A hardenable liquid, such as poly (dimethylsiloxane) is then introduced into the mold cavity and hardened to form a platform structure as well as to mold the microfluidic flow path network having channels, reservoirs and ports. Pre-fabricated elbows, T's and other joints are used to interconnect various building block elements together. After hardening the liquid the building blocks are removed from the platform structure to make available the channels, cavities and ports within the platform structure. Microdevices may be embedded within the cast polymer-based platform, or bonded to the platform structure subsequent to molding, to create an integrated microfluidic system. In this manner, the new microfluidic platform is versatile and capable of quickly generating prototype systems, and could easily be adapted to a manufacturing setting.

Building Blocks for Sustainable Communities: Assistance from Grantees

EPA Pesticide Factsheets

EPA awarded Building Blocks for Sustainable Communities grants to four nonprofit organizations with extensive expertise in community sustainability. These organizations deliver technical assistance to communities.

Block Play and Mathematics Learning in Preschool: The Effects of Building Complexity, Peer and Teacher Interactions in the Block Area, and Replica Play Materials

ERIC Educational Resources Information Center

Trawick-Smith, Jeffrey; Swaminathan, Sudha; Baton, Brooke; Danieluk, Courtney; Marsh, Samantha; Szarwacki, Monika

2017-01-01

Block play has been included in early childhood classrooms for over a century, yet few studies have examined its effects on learning. Several previous investigations indicate that the complexity of block building is associated with math ability, but these studies were often conducted in adult-guided, laboratory settings. In the present…

DNA-Templated Polymerization of Side-Chain-Functionalized Peptide Nucleic Acid Aldehydes

PubMed Central

Kleiner, Ralph E.; Brudno, Yevgeny; Birnbaum, Michael E.; Liu, David R.

2009-01-01

The DNA-templated polymerization of synthetic building blocks provides a potential route to the laboratory evolution of sequence-defined polymers with structures and properties not necessarily limited to those of natural biopolymers. We previously reported the efficient and sequence-specific DNA-templated polymerization of peptide nucleic acid (PNA) aldehydes. Here, we report the enzyme-free, DNA-templated polymerization of side-chain-functionalized PNA tetramer and pentamer aldehydes. We observed that the polymerization of tetramer and pentamer PNA building blocks with a single lysine-based side chain at various positions in the building block could proceed efficiently and sequence-specifically. In addition, DNA-templated polymerization also proceeded efficiently and in a sequence-specific manner with pentamer PNA aldehydes containing two or three lysine side chains in a single building block to generate more densely functionalized polymers. To further our understanding of side-chain compatibility and expand the capabilities of this system, we also examined the polymerization efficiencies of 20 pentamer building blocks each containing one of five different side-chain groups and four different side-chain regio- and stereochemistries. Polymerization reactions were efficient for all five different side-chain groups and for three of the four combinations of side-chain regio- and stereochemistries. Differences in the efficiency and initial rate of polymerization correlate with the apparent melting temperature of each building block, which is dependent on side-chain regio- and stereochemistry, but relatively insensitive to side-chain structure among the substrates tested. Our findings represent a significant step towards the evolution of sequence-defined synthetic polymers and also demonstrate that enzyme-free nucleic acid-templated polymerization can occur efficiently using substrates with a wide range of side-chain structures, functionalization positions within each building block, and functionalization densities. PMID:18341334

Total synthesis of TMG-chitotriomycin based on an automated electrochemical assembly of a disaccharide building block.

PubMed

Isoda, Yuta; Sasaki, Norihiko; Kitamura, Kei; Takahashi, Shuji; Manmode, Sujit; Takeda-Okuda, Naoko; Tamura, Jun-Ichi; Nokami, Toshiki; Itoh, Toshiyuki

2017-01-01

The total synthesis of TMG-chitotriomycin using an automated electrochemical synthesizer for the assembly of carbohydrate building blocks is demonstrated. We have successfully prepared a precursor of TMG-chitotriomycin, which is a structurally-pure tetrasaccharide with typical protecting groups, through the methodology of automated electrochemical solution-phase synthesis developed by us. The synthesis of structurally well-defined TMG-chitotriomycin has been accomplished in 10-steps from a disaccharide building block.

Big Questions: The Ultimate Building Blocks of Matter

ScienceCinema

Lincoln, Don

2018-01-16

The Standard Model of particle physics treats quarks and leptons as having no size at all. Quarks are found inside protons and neutrons and the most familiar lepton is the electron. While the best measurements to date support that idea, there is circumstantial evidence that suggests that perhaps the these tiny particles might be composed of even smaller building blocks. This video explains this circumstantial evidence and introduces some very basic ideas of what those building blocks might be.

Building Blocks for Personal Brands

ERIC Educational Resources Information Center

Thomas, Lisa Carlucci

2011-01-01

In this article, the author discusses the four essential building blocks for personal brands: (1) name; (2) message; (3) channels; and (4) bridges. However, outstanding building materials can only take a person so far. The author emphasizes that vision, determination, faith, a sense of humor, and humility are also required.

Damage Assessment Map from Interferometric Coherence

NASA Astrophysics Data System (ADS)

Yun, S.; Fielding, E. J.; Simons, M.; Rosen, P. A.; Owen, S. E.; Webb, F.

2010-12-01

Large earthquakes cause buildings to collapse, which often claims the lives of many. For example, 2010 Haiti earthquake killed about 230,000 people, with about 280,000 buildings collapsed or severely damaged. When a major earthquake hits an urban area, one of the most critical information for rescue operations is rapid and accurate assessment of building-collapse areas. From a study on 2003 Bam earthquake in Iran, interferometric coherence was proved useful for earthquake damage assessment (Fielding et al., 2005) when similar perpendicular baselines can be found for pre- and coseismic interferometric pairs and when there is little temporal and volume decorrelation. In this study we develop a new algorithm to create a more robust and accurate damage assessment map using interferometric coherence despite different interferometric baselines and with other decorrelation sources. We test the algorithm on a building block that recently underwent demolition, which is a proxy for building collapse due to earthquakes, for new construction in the City of Pasadena, California. The size of the building block is about 150 m E-W and 300 m N-S, and the demolition project started on April 23, 2007 and continued until January 22, 2008. After we process Japanese L-band ALOS PALSAR data with ROI_PAC, an interferometric coherence map that spans the demolition period is registered to a coherence map before the demolition, and the relative bias of the coherence values are removed, then a causality constraint is applied to enhance the change due to demolition. The results show clear change in coherence at the demolition site. We improve the signal-to-noise ratio of the coherence change at the demolition site from 17.3 (for simple difference) to 44.6 (with the new algorithm). The damage assessment map algorithm will become more useful with the emergence of InSAR missions with more frequent data acquisition, such as Sentinel-1 and DESDynI.

Shaping Crystal-Crystal Phase Transitions

NASA Astrophysics Data System (ADS)

Du, Xiyu; van Anders, Greg; Dshemuchadse, Julia; Glotzer, Sharon

Previous computational and experimental studies have shown self-assembled structure depends strongly on building block shape. New synthesis techniques have led to building blocks with reconfigurable shape and it has been demonstrated that building block reconfiguration can induce bulk structural reconfiguration. However, we do not understand systematically how this transition happens as a function of building block shape. Using a recently developed ``digital alchemy'' framework, we study the thermodynamics of shape-driven crystal-crystal transitions. We find examples of shape-driven bulk reconfiguration that are accompanied by first-order phase transitions, and bulk reconfiguration that occurs without any thermodynamic phase transition. Our results suggest that for well-chosen shapes and structures, there exist facile means of bulk reconfiguration, and that shape-driven bulk reconfiguration provides a viable mechanism for developing functional materials.

3DGRAPE - THREE DIMENSIONAL GRIDS ABOUT ANYTHING BY POISSON'S EQUATION

NASA Technical Reports Server (NTRS)

Sorenson, R. L.

1994-01-01

The ability to treat arbitrary boundary shapes is one of the most desirable characteristics of a method for generating grids. 3DGRAPE is designed to make computational grids in or about almost any shape. These grids are generated by the solution of Poisson's differential equations in three dimensions. The program automatically finds its own values for inhomogeneous terms which give near-orthogonality and controlled grid cell height at boundaries. Grids generated by 3DGRAPE have been applied to both viscous and inviscid aerodynamic problems, and to problems in other fluid-dynamic areas. 3DGRAPE uses zones to solve the problem of warping one cube into the physical domain in real-world computational fluid dynamics problems. In a zonal approach, a physical domain is divided into regions, each of which maps into its own computational cube. It is believed that even the most complicated physical region can be divided into zones, and since it is possible to warp a cube into each zone, a grid generator which is oriented to zones and allows communication across zonal boundaries (where appropriate) solves the problem of topological complexity. 3DGRAPE expects to read in already-distributed x,y,z coordinates on the bodies of interest, coordinates which will remain fixed during the entire grid-generation process. The 3DGRAPE code makes no attempt to fit given body shapes and redistribute points thereon. Body-fitting is a formidable problem in itself. The user must either be working with some simple analytical body shape, upon which a simple analytical distribution can be easily effected, or must have available some sophisticated stand-alone body-fitting software. 3DGRAPE does not require the user to supply the block-to-block boundaries nor the shapes of the distribution of points. 3DGRAPE will typically supply those block-to-block boundaries simply as surfaces in the elliptic grid. Thus at block-to-block boundaries the following conditions are obtained: (1) grids lines will match up as they approach the block-to-block boundary from either side, (2) grid lines will cross the boundary with no slope discontinuity, (3) the spacing of points along the line piercing the boundary will be continuous, (4) the shape of the boundary will be consistent with the surrounding grid, and (5) the distribution of points on the boundary will be reasonable in view of the surrounding grid. 3DGRAPE offers a powerful building-block approach to complex 3-D grid generation, but is a low-level tool. Users may build each face of each block as they wish, from a wide variety of resources. 3DGRAPE uses point-successive-over-relaxation (point-SOR) to solve the Poisson equations. This method is slow, although it does vectorize nicely. Any number of sophisticated graphics programs may be used on the stored output file of 3DGRAPE though it lacks interactive graphics. Versatility was a prominent consideration in developing the code. The block structure allows a great latitude in the problems it can treat. As the acronym implies, this program should be able to handle just about any physical region into which a computational cube or cubes can be warped. 3DGRAPE was written in FORTRAN 77 and should be machine independent. It was originally developed on a Cray under COS and tested on a MicroVAX 3200 under VMS 5.1.

Automate Your Physical Plant Using the Building Block Approach.

ERIC Educational Resources Information Center

Michaelson, Matt

1998-01-01

Illustrates how Mount Saint Vincent University (Halifax), by upgrading the control and monitoring of one building or section of the school at a time, could produce savings in energy and operating costs and improve the environment. Explains a gradual, "building block" approach to facility automation that provides flexibility without a…

Building Numbers from Primes

ERIC Educational Resources Information Center

Burkhart, Jerry

2009-01-01

Prime numbers are often described as the "building blocks" of natural numbers. This article shows how the author and his students took this idea literally by using prime factorizations to build numbers with blocks. In this activity, students explore many concepts of number theory, including the relationship between greatest common factors and…

26 CFR 1.1248-2 - Earnings and profits attributable to a block of stock in simple cases.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Earnings and profits attributable to a block of... Gains and Losses § 1.1248-2 Earnings and profits attributable to a block of stock in simple cases. (a... person sells or exchanges a block of stock (as defined in paragraph (b) of this section) in a foreign...

2. OBLIQUE VIEW LOOKING NORTHWEST FROM 21ST STREET VIADUCT TOWARDS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. OBLIQUE VIEW LOOKING NORTHWEST FROM 21ST STREET VIADUCT TOWARDS 2000 BLOCK OF MORRIS AVENUE WITH HEAVIEST CORNER ON EARTH BUILDINGS (TOP LEFT) AND COMER BUILDING (TOP RIGHT) - Morris Avenue Warehouse District, 2000-2400 blocks of Morris Avenue & 2100-2500 blocks of First Avenue, North, Birmingham, Jefferson County, AL

Automated electrochemical assembly of the protected potential TMG-chitotriomycin precursor based on rational optimization of the carbohydrate building block.

PubMed

Nokami, Toshiki; Isoda, Yuta; Sasaki, Norihiko; Takaiso, Aki; Hayase, Shuichi; Itoh, Toshiyuki; Hayashi, Ryutaro; Shimizu, Akihiro; Yoshida, Jun-ichi

2015-03-20

The anomeric arylthio group and the hydroxyl-protecting groups of thioglycosides were optimized to construct carbohydrate building blocks for automated electrochemical solution-phase synthesis of oligoglucosamines having 1,4-β-glycosidic linkages. The optimization study included density functional theory calculations, measurements of the oxidation potentials, and the trial synthesis of the chitotriose trisaccharide. The automated synthesis of the protected potential N,N,N-trimethyl-d-glucosaminylchitotriomycin precursor was accomplished by using the optimized building block.

Total synthesis of TMG-chitotriomycin based on an automated electrochemical assembly of a disaccharide building block

PubMed Central

Isoda, Yuta; Sasaki, Norihiko; Kitamura, Kei; Takahashi, Shuji; Manmode, Sujit; Takeda-Okuda, Naoko; Tamura, Jun-ichi

2017-01-01

The total synthesis of TMG-chitotriomycin using an automated electrochemical synthesizer for the assembly of carbohydrate building blocks is demonstrated. We have successfully prepared a precursor of TMG-chitotriomycin, which is a structurally-pure tetrasaccharide with typical protecting groups, through the methodology of automated electrochemical solution-phase synthesis developed by us. The synthesis of structurally well-defined TMG-chitotriomycin has been accomplished in 10-steps from a disaccharide building block. PMID:28684973

Strategies for Controlled Placement of Nanoscale Building Blocks

PubMed Central

2007-01-01

The capability of placing individual nanoscale building blocks on exact substrate locations in a controlled manner is one of the key requirements to realize future electronic, optical, and magnetic devices and sensors that are composed of such blocks. This article reviews some important advances in the strategies for controlled placement of nanoscale building blocks. In particular, we will overview template assisted placement that utilizes physical, molecular, or electrostatic templates, DNA-programmed assembly, placement using dielectrophoresis, approaches for non-close-packed assembly of spherical particles, and recent development of focused placement schemes including electrostatic funneling, focused placement via molecular gradient patterns, electrodynamic focusing of charged aerosols, and others. PMID:21794185

Label-Free Fluorescent DNA Dendrimers for microRNA Detection Based On Nonlinear Hybridization Chain Reaction-Mediated Multiple G-Quadruplex with Low Background Signal.

PubMed

Xue, Qingwang; Liu, Chunxue; Li, Xia; Dai, Li; Wang, Huaisheng

2018-04-18

Various fluorescent sensing systems for miRNA detection have been developed, but they mostly contain enzymatic amplification reactions and label procedures. The strict reaction conditions of tool enzymes and the high cost of labeling limit their potential applications, especially in complex biological matrices. Here, we have addressed the difficult problems and report a strategy for label-free fluorescent DNA dendrimers based on enzyme-free nonlinear hybridization chain reaction (HCR)-mediated multiple G-quadruplex for simple, sensitive, and selective detection of miRNAs with low-background signal. In the strategy, a split G-quadruplex (3:1) sequence is ingeniously designed at both ends of two double-stranded DNAs, which is exploited as building blocks for nonlinear HCR assembly, thereby acquiring a low background signal. A hairpin switch probe (HSP) was employed as recognition and transduction element. Upon sensing the target miRNA, the nonlinear HCR assembly of two blocks (blocks-A and blocks-B) was initiated with the help of two single-stranded DNA assistants, resulting in chain-branching growth of DNA dendrimers with multiple G-quadruplex incorporation. With the zinc(II)-protoporphyrin IX (ZnPPIX) selectively intercalated into the multiple G-quadruplexes, fluorescent DNA dendrimers were obtained, leading to an exponential fluorescence intensity increase. Benefiting from excellent performances of nonlinear HCR and low background signal, this strategy possesses the characteristics of a simplified reaction operation process, as well as high sensitivity. Moreover, the proposed fluorescent sensing strategy also shows preferable selectivity, and can be implemented without modified DNA blocks. Importantly, the strategy has also been tested for miRNA quantification with high confidence in breast cancer cells. Thus, this proposed strategy for label-free fluorescent DNA dendrimers based on a nonlinear HCR-mediated multiple G-quadruplex will be turned into an alternative approach for simple, sensitive, and selective miRNA quantification.

Local anesthesia for inguinal hernia repair step-by-step procedure.

PubMed Central

Amid, P K; Shulman, A G; Lichtenstein, I L

1994-01-01

OBJECTIVE. The authors introduce a simple six-step infiltration technique that results in satisfactory local anesthesia and prolonged postoperative analgesia, requiring a maximum of 30 to 40 mL of local anesthetic solution. SUMMARY BACKGROUND DATA. For the last 20 years, more than 12,000 groin hernia repairs have been performed under local anesthesia at the Lichtenstein Hernia Institute. Initially, field block was the mean of achieving local anesthesia. During the last 5 years, a simple infiltration technique has been used because the field block was more time consuming and required larger volume of the local anesthetic solution. Furthermore, because of the blind nature of the procedure, it did not always result in satisfactory anesthesia and, at times, accidental needle puncture of the ilioinguinal nerve resulted in prolonged postoperative pain, burning, or electric shock sensation within the field of the ilioinguinal nerve innervation. METHODS. More than 12,000 patients underwent operations in a private practice setting in general hospitals. RESULTS. For 2 decades, more than 12,000 adult patients with reducible groin hernias satisfactorily underwent operations under local anesthesia without complications. CONCLUSIONS. The preferred choice of anesthesia for all reducible adult inguinal hernia repair is local. It is safe, simple, effective, and economical, without postanesthesia side effects. Furthermore, local anesthesia administered before the incision produces longer postoperative analgesia because local infiltration, theoretically, inhibits build-up of local nociceptive molecules and, therefore, there is better pain control in the postoperative period. Images Figure 1. Figure 2. PMID:7986138

Collective strategy for obstacle navigation during cooperative transport by ants.

PubMed

McCreery, Helen F; Dix, Zachary A; Breed, Michael D; Nagpal, Radhika

2016-11-01

Group cohesion and consensus have primarily been studied in the context of discrete decisions, but some group tasks require making serial decisions that build on one another. We examine such collective problem solving by studying obstacle navigation during cooperative transport in ants. In cooperative transport, ants work together to move a large object back to their nest. We blocked cooperative transport groups of Paratrechina longicornis with obstacles of varying complexity, analyzing groups' trajectories to infer what kind of strategy the ants employed. Simple strategies require little information, but more challenging, robust strategies succeed with a wider range of obstacles. We found that transport groups use a stochastic strategy that leads to efficient navigation around simple obstacles, and still succeeds at difficult obstacles. While groups navigating obstacles preferentially move directly toward the nest, they change their behavior over time; the longer the ants are obstructed, the more likely they are to move away from the nest. This increases the chance of finding a path around the obstacle. Groups rapidly changed directions and rarely stalled during navigation, indicating that these ants maintain consensus even when the nest direction is blocked. Although some decisions were aided by the arrival of new ants, at many key points, direction changes were initiated within the group, with no apparent external cause. This ant species is highly effective at navigating complex environments, and implements a flexible strategy that works for both simple and more complex obstacles. © 2016. Published by The Company of Biologists Ltd.

Inquiring Minds

Science.gov Websites

and leptons seem to be the fundamental building blocks - but perhaps there is something even smaller properties of the fundamental building blocks of our universe, there are untold mysteries still to solve

Measuring health systems strength and its impact: experiences from the African Health Initiative.

PubMed

Sherr, Kenneth; Fernandes, Quinhas; Kanté, Almamy M; Bawah, Ayaga; Condo, Jeanine; Mutale, Wilbroad

2017-12-21

Health systems are essential platforms for accessible, quality health services, and population health improvements. Global health initiatives have dramatically increased health resources; however, funding to strengthen health systems has not increased commensurately, partially due to concerns about health system complexity and evidence gaps demonstrating health outcome improvements. In 2009, the African Health Initiative of the Doris Duke Charitable Foundation began supporting Population Health Implementation and Training Partnership projects in five sub-Saharan African countries (Ghana, Mozambique, Rwanda, Tanzania, and Zambia) to catalyze significant advances in strengthening health systems. This manuscript reflects on the experience of establishing an evaluation framework to measure health systems strength, and associate measures with health outcomes, as part of this Initiative. Using the World Health Organization's health systems building block framework, the Partnerships present novel approaches to measure health systems building blocks and summarize data across and within building blocks to facilitate analytic procedures. Three Partnerships developed summary measures spanning the building blocks using principal component analysis (Ghana and Tanzania) or the balanced scorecard (Zambia). Other Partnerships developed summary measures to simplify multiple indicators within individual building blocks, including health information systems (Mozambique), and service delivery (Rwanda). At the end of the project intervention period, one to two key informants from each Partnership's leadership team were asked to list - in rank order - the importance of the six building blocks in relation to their intervention. Though there were differences across Partnerships, service delivery and information systems were reported to be the most common focus of interventions, followed by health workforce and leadership and governance. Medical products, vaccines and technologies, and health financing, were the building blocks reported to be of lower focus. The African Health Initiative experience furthers the science of evaluation for health systems strengthening, highlighting areas for further methodological development - including the development of valid, feasible measures sensitive to interventions in multiple contexts (particularly in leadership and governance) and describing interactions across building blocks; in developing summary statistics to facilitate testing intervention effects on health systems and associations with health status; and designing appropriate analytic models for complex, multi-level open health systems.

Systems thinking in practice: the current status of the six WHO building blocks for health system strengthening in three BHOMA intervention districts of Zambia: a baseline qualitative study.

PubMed

Mutale, Wilbroad; Bond, Virginia; Mwanamwenge, Margaret Tembo; Mlewa, Susan; Balabanova, Dina; Spicer, Neil; Ayles, Helen

2013-08-01

The primary bottleneck to achieving the MDGs in low-income countries is health systems that are too fragile to deliver the volume and quality of services to those in need. Strong and effective health systems are increasingly considered a prerequisite to reducing the disease burden and to achieving the health MDGs. Zambia is one of the countries that are lagging behind in achieving millennium development targets. Several barriers have been identified as hindering the progress towards health related millennium development goals. Designing an intervention that addresses these barriers was crucial and so the Better Health Outcomes through Mentorship (BHOMA) project was designed to address the challenges in the Zambia's MOH using a system wide approach. We applied systems thinking approach to describe the baseline status of the Six WHO building blocks for health system strengthening. A qualitative study was conducted looking at the status of the Six WHO building blocks for health systems strengthening in three BHOMA districts. We conducted Focus group discussions with community members and In-depth Interviews with key informants. Data was analyzed using Nvivo version 9. The study showed that building block specific weaknesses had cross cutting effect in other health system building blocks which is an essential element of systems thinking. Challenges noted in service delivery were linked to human resources, medical supplies, information flow, governance and finance building blocks either directly or indirectly. Several barriers were identified as hindering access to health services by the local communities. These included supply side barriers: Shortage of qualified health workers, bad staff attitude, poor relationships between community and health staff, long waiting time, confidentiality and the gender of health workers. Demand side barriers: Long distance to health facility, cost of transport and cultural practices. Participating communities seemed to lack the capacity to hold health workers accountable for the drugs and services. The study has shown that building block specific weaknesses had cross cutting effect in other health system building blocks. These linkages emphasised the need to use system wide approaches in assessing the performance of health system strengthening interventions.

Benzyl alcohol and block copolymer micellar lithography: a versatile route to assembling gold and in situ generated titania nanoparticles into uniform binary nanoarrays.

PubMed

Polleux, Julien; Rasp, Matthias; Louban, Ilia; Plath, Nicole; Feldhoff, Armin; Spatz, Joachim P

2011-08-23

Simultaneous synthesis and assembly of nanoparticles that exhibit unique physicochemical properties are critically important for designing new functional devices at the macroscopic scale. In the present study, we report a simple version of block copolymer micellar lithography (BCML) to synthesize gold and titanium dioxide (TiO(2)) nanoarrays by using benzyl alcohol (BnOH) as a solvent. In contrast to toluene, BnOH can lead to the formation of various gold nanopatterns via salt-induced micellization of polystyrene-block-poly(vinylpyridine) (PS-b-P2VP). In the case of titania, the use of BCML with a nonaqueous sol-gel method, the "benzyl alcohol route", enables the fabrication of nanopatterns made of quasi-hexagonally organized particles or parallel wires upon aging a (BnOH-TiCl(4)-PS(846)-b-P2VP(171))-containing solution for four weeks to grow TiO(2) building blocks in situ. This approach was found to depend mainly on the relative lengths of the polymer blocks, which allows nanoparticle-induced micellization and self-assembly during solvent evaporation. Moreover, this versatile route enables the design of uniform and quasi-ordered gold-TiO(2) binary nanoarrays with a precise particle density due to the absence of graphoepitaxy during the deposition of TiO(2) onto gold nanopatterns. © 2011 American Chemical Society

Rapid and annealing-free self-assembly of DNA building blocks for 3D hydrogel chaperoned by cationic comb-type copolymers.

PubMed

Zhang, Zheng; Wu, Yuyang; Yu, Feng; Niu, Chaoqun; Du, Zhi; Chen, Yong; Du, Jie

2017-10-01

The construction and self-assembly of DNA building blocks are the foundation of bottom-up development of three-dimensional DNA nanostructures or hydrogels. However, most self-assembly from DNA components is impeded by the mishybridized intermediates or the thermodynamic instability. To enable rapid production of complicated DNA objects with high yields no need for annealing process, herein different DNA building blocks (Y-shaped, L- and L'-shaped units) were assembled in presence of a cationic comb-type copolymer, poly (L-lysine)-graft-dextran (PLL-g-Dex), under physiological conditions. The results demonstrated that PLL-g-Dex not only significantly promoted the self-assembly of DNA blocks with high efficiency, but also stabilized the assembled multi-level structures especially for promoting the complicated 3D DNA hydrogel formation. This study develops a novel strategy for rapid and high-yield production of DNA hydrogel even derived from instable building blocks at relatively low DNA concentrations, which would endow DNA nanotechnology for more practical applications.

An Approach for On-Board Software Building Blocks Cooperation and Interfaces Definition

NASA Astrophysics Data System (ADS)

Pascucci, Dario; Campolo, Giovanni; Candia, Sante; Lisio, Giovanni

2010-08-01

This paper provides an insight on the Avionic SW architecture developed by Thales Alenia Space Italy (TAS-I) to achieve structuring of the OBSW as a set of self-standing and re-usable building blocks. It is initially described the underlying framework for building blocks cooperation, which is based on ECSSE-70 packets forwarding (for services request to a building block) and standard parameters exchange for data communication. Subsequently it is discussed the high level of flexibility and scalability of the resulting architecture, reporting as example an implementation of the Failure Detection, Isolation and Recovery (FDIR) function which exploits the proposed architecture. The presented approach evolves from avionic SW architecture developed in the scope of the project PRIMA (Mult-Purpose Italian Re-configurable Platform) and has been adopted for the Sentinel-1 Avionic Software (ASW).

Bottom-up construction of a superstructure in a porous uranium-organic crystal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Peng; Vermeulen, Nicolaas A.; Malliakas, Christos D.

Bottom-up construction of highly intricate structures from simple building blocks remains one of the most difficult challenges in chemistry. We report a structurally complex, mesoporous uranium-based metal-organic framework (MOF) made from simple starting components. The structure comprises 10 uranium nodes and seven tricarboxylate ligands (both crystallographically nonequivalent), resulting in a 173.3-angstrom cubic unit cell enclosing 816 uranium nodes and 816 organic linkers—the largest unit cell found to date for any nonbiological material. The cuboctahedra organize into pentagonal and hexagonal prismatic secondary structures, which then form tetrahedral and diamond quaternary topologies with unprecedented complexity. This packing results in the formation ofmore » colossal icosidodecahedral and rectified hexakaidecahedral cavities with internal diameters of 5.0 nanometers and 6.2 nanometers, respectively—ultimately giving rise to the lowest-density MOF reported to date.« less

Exploitation of Ubiquitous Wi-Fi Devices as Building Blocks for Improvised Motion Detection Systems.

PubMed

Soldovieri, Francesco; Gennarelli, Gianluca

2016-02-27

This article deals with a feasibility study on the detection of human movements in indoor scenarios based on radio signal strength variations. The sensing principle exploits the fact that the human body interacts with wireless signals, introducing variations of the radiowave fields due to shadowing and multipath phenomena. As a result, human motion can be inferred from fluctuations of radiowave power collected by a receiving terminal. In this paper, we investigate the potentialities of widely available wireless communication devices in order to develop an improvised motion detection system (IMDS). Experimental tests are performed in an indoor environment by using a smartphone as a Wi-Fi access point and a laptop with dedicated software as a receiver. Simple detection strategies tailored for real-time operation are implemented to process the received signal strength measurements. The achieved results confirm the potentialities of the simple system here proposed to reliably detect human motion in operational conditions.

Coordination Covalent Frameworks: A New Route for Synthesis and Expansion of Functional Porous Materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elsaidi, Sameh K.; Mohamed, Mona H.; Loring, John S.

The synthetic approaches for fine-tuning the structural properties of coordination polymers or metal organic frameworks have exponentially grown during the last decade. This is due to the control over the properties of the resulting structures such as stability, pore size, pore chemis-try and surface area for myriad possible applications. Herein, we present a new class of porous materials called Covalent Coordination Frameworks (CCFs) that were designed and effectively synthesized using a two-step reticular chemistry approach. During the first step, trigonal prismatic molecular building block was isolated using 4-aminobenazoic acid and Cr (III) salt, subsequently in the second step the polymerizationmore » of the isolated molecular building blocks (MBBs) takes place by the formation of strong covalent bonds where small organic molecules can connect the MBBs forming extended porous CCF materials. All the isolated CCFs were found to be permanently porous while the discrete MBB were non-porous. This approach would inevitably open a feasible path for the applications of reticular chemistry and the synthesis of novel porous materials with various topologies under ambient conditions using simple organic molecules and versatile MBBs with different functionalities which would not be possible using the traditional one step approach« less

15. WEST SIDE OF 1900 BLOCK, PACIFIC AVE. FROM RIGHT; ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. WEST SIDE OF 1900 BLOCK, PACIFIC AVE. FROM RIGHT; 1920-22 PACIFIC AVE., WIEGAL COMPANY CANDY FACTORY (1904); 1924-26 PACIFIC AVE., CAMPBELL BUILDING (DAVIS BUILDING) (1890); 1928-30 PACIFIC AVE., REESE-CRANDALL & REDMAN BUILDING, (1890); 1932-36 PACIFIC AVE., MC DONALD & SMITH BUILDING (1890); 1938-48 PACIFIC AVE., F.S. HARMON COMPANY WAREHOUSE (1908), DESIGNED BY CARL AUGUST DARMER. - Union Depot Area Study, Tacoma, Pierce County, WA

Application of soil block without burning process and calcium silicate panels as building wall in mountainous area

NASA Astrophysics Data System (ADS)

Noerwasito, Vincentius Totok; Nasution, Tanti Satriana Rosary

2017-11-01

Utilization of local building materials in a residential location in mountainous area is very important, considering local material as a low-energy building material because of low transport energy. The local building materials used in this study are walls made from soil blocks. The material was made by the surrounding community from compacted soil without burning process. To maximize the potential of soil block to the outdoor temperature in the mountains, it is necessary to add non-local building materials as an insulator from the influence of the outside air. The insulator was calcium silicate panel. The location of the research is Trawas sub-district, Mojokerto regency, which is a mountainous area. The research problem is on applying the composition of local materials and calcium silicate panels that it will be able to meet the requirements as a wall building material and finding to what extent the impact of the wall against indoor temperature. The result from this research was the application of soil block walls insulated by calcium silicate panels in a building model. Besides, because of the utilization of those materials, the building has a specific difference between indoor and outdoor temperature. Thus, this model can be applied in mountainous areas in Indonesia.

The Origin and Early Evolution of Membrane Proteins

NASA Technical Reports Server (NTRS)

Pohorille, Andrew; Schweighofer, Karl; Wilson, Michael A.

2005-01-01

Membrane proteins mediate functions that are essential to all cells. These functions include transport of ions, nutrients and waste products across cell walls, capture of energy and its transduction into the form usable in chemical reactions, transmission of environmental signals to the interior of the cell, cellular growth and cell volume regulation. In the absence of membrane proteins, ancestors of cell (protocells), would have had only very limited capabilities to communicate with their environment. Thus, it is not surprising that membrane proteins are quite common even in simplest prokaryotic cells. Considering that contemporary membrane channels are large and complex, both structurally and functionally, a question arises how their presumably much simpler ancestors could have emerged, perform functions and diversify in early protobiological evolution. Remarkably, despite their overall complexity, structural motifs in membrane proteins are quite simple, with a-helices being most common. This suggests that these proteins might have evolved from simple building blocks. To explain how these blocks could have organized into functional structures, we performed large-scale, accurate computer simulations of folding peptides at a water-membrane interface, their insertion into the membrane, self-assembly into higher-order structures and function. The results of these simulations, combined with analysis of structural and functional experimental data led to the first integrated view of the origin and early evolution of membrane proteins.

How Crossover Speeds up Building Block Assembly in Genetic Algorithms.

PubMed

Sudholt, Dirk

2017-01-01

We reinvestigate a fundamental question: How effective is crossover in genetic algorithms in combining building blocks of good solutions? Although this has been discussed controversially for decades, we are still lacking a rigorous and intuitive answer. We provide such answers for royal road functions and OneMax, where every bit is a building block. For the latter, we show that using crossover makes every ([Formula: see text]+[Formula: see text]) genetic algorithm at least twice as fast as the fastest evolutionary algorithm using only standard bit mutation, up to small-order terms and for moderate [Formula: see text] and [Formula: see text]. Crossover is beneficial because it can capitalize on mutations that have both beneficial and disruptive effects on building blocks: crossover is able to repair the disruptive effects of mutation in later generations. Compared to mutation-based evolutionary algorithms, this makes multibit mutations more useful. Introducing crossover changes the optimal mutation rate on OneMax from [Formula: see text] to [Formula: see text]. This holds both for uniform crossover and k-point crossover. Experiments and statistical tests confirm that our findings apply to a broad class of building block functions.

Single molecule magnets from magnetic building blocks

NASA Astrophysics Data System (ADS)

Kroener, W.; Paretzki, A.; Cervetti, C.; Hohloch, S.; Rauschenbach, S.; Kern, K.; Dressel, M.; Bogani, L.; M&üLler, P.

2013-03-01

We provide a basic set of magnetic building blocks that can be rationally assembled, similar to magnetic LEGO bricks, in order to create a huge variety of magnetic behavior. Using rare-earth centers and multipyridine ligands, fine-tuning of intra and intermolecular exchange interaction is demonstrated. We have investigated a series of molecules with monomeric, dimeric and trimeric lanthanide centers using SQUID susceptometry and Hall bar magnetometry. A home-made micro-Hall-probe magnetometer was used to measure magnetic hysteresis loops at mK temperatures and fields up to 17 T. All compounds show hysteresis below blocking temperatures of 3 to 4 K. The correlation of the assembly of the building blocks with the magnetic properties will be discussed.

Embeddable Reconfigurable Neuroprocessors

NASA Technical Reports Server (NTRS)

Daud, Taher; Duong, Tuan; Langenbacher, Harry; Tran, Mua; Thakoor, Anil

1993-01-01

Reconfigurable and cascadable building block neural network chips, fabricated using analog VLSI design tools, are interfaced to a PC. The building block chip designs, the cascadability and the hardware-in-the-loop supervised learning aspects of these chips are described.

A monomer-trimer model supports intermittent glucagon fibril growth

NASA Astrophysics Data System (ADS)

Košmrlj, Andrej; Cordsen, Pia; Kyrsting, Anders; Otzen, Daniel E.; Oddershede, Lene B.; Jensen, Mogens H.

2015-03-01

We investigate in vitro fibrillation kinetics of the hormone peptide glucagon at various concentrations using confocal microscopy and determine the glucagon fibril persistence length 60μm. At all concentrations we observe that periods of individual fibril growth are interrupted by periods of stasis. The growth probability is large at high and low concentrations and is reduced for intermediate glucagon concentrations. To explain this behavior we propose a simple model, where fibrils come in two forms, one built entirely from glucagon monomers and one entirely from glucagon trimers. The opposite building blocks act as fibril growth blockers, and this generic model reproduces experimental behavior well.

Carbon Nanotubes: Molecular Electronic Components

NASA Technical Reports Server (NTRS)

Srivastava, Deepak; Saini, Subhash; Menon, Madhu

1997-01-01

The carbon Nanotube junctions have recently emerged as excellent candidates for use as the building blocks in the formation of nanoscale molecular electronic networks. While the simple joint of two dissimilar tubes can be generated by the introduction of a pair of heptagon-pentagon defects in an otherwise perfect hexagonal graphene sheet, more complex joints require other mechanisms. In this work we explore structural characteristics of complex 3-point junctions of carbon nanotubes using a generalized tight-binding molecular-dynamics scheme. The study of pi-electron local densities of states (LDOS) of these junctions reveal many interesting features, most prominent among them being the defect-induced states in the gap.

Living fungal hyphae-templated porous gold microwires using nanoparticles as building blocks

NASA Astrophysics Data System (ADS)

Rehman, Asma; Majeed, Muhammad Irfan; Ihsan, Ayesha; Hussain, Syed Zajif; Saif-ur-Rehman; Ghauri, Muhammad Afzal; Khalid, Zafar M.; Hussain, Irshad

2011-12-01

A simple and environmentally benign green method is reported to decorate growing fungal hyphae with high loading of gold nanoparticles, which were initially produced using aqueous tea extract as a sole reducing/stabilizing agent. Inoculation of fungal spores in aqueous suspension of nanoparticles led to the growth of intensely red-coloured fungal hyphae due to the accumulation of gold nanoparticles. Heat treatment of these hybrid materials led to the formation of porous gold microwires. This report is thus an interesting example of using green and sustainable approach to produce nanostructured materials which have potential applications in catalysis, sensing and electronics.

Novel multiform morphologies of hydroxyapatite: Synthesis and growth mechanism

NASA Astrophysics Data System (ADS)

Mary, I. Reeta; Sonia, S.; Viji, S.; Mangalaraj, D.; Viswanathan, C.; Ponpandian, N.

2016-01-01

Morphological evolution of materials becomes a prodigious challenge due to their key role in defining their functional properties and desired applications. Herein, we report the synthesis of hydroxyapatite (HAp) microstructures with multiform morphologies, such as spheres, cubes, hexagonal rods and nested bundles constructed from their respective nanoscale building blocks via a simple cost effective hydro/solvothermal method. A possible formation mechanism of diverse morphologies of HAp has been presented. Structural analysis based on X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy confirms the purity of the HAp microstructures. The multiform morphologies of HAp were corroborated by using Field emission scanning electron microscope (FESEM).

Selective Oxidative Esterification from Two Different Alcohols via Photoredox Catalysis.

PubMed

Yi, Hong; Hu, Xia; Bian, Changliang; Lei, Aiwen

2017-01-10

Esters functionalities are important building blocks that are extensively used in the chemical industry and academic laboratories. Direct oxidative esterification from easy-available alcohols to esters would be a much more appealing approach, especially using O 2 as terminal oxidant. Inputting external energy by photocatalysis for dioxygen activation, a mild and simple method for ester synthesis from two different alcohols has been achieved in this work. This reaction is performed under neutral conditions using O 2 as the terminal oxidant. A variety of primary alcohols, especially long chain alcohols and secondary alcohols are tolerated in this system. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-speed observation of ZnO microspherical crystals produced by laser ablation (Conference Presentation)

NASA Astrophysics Data System (ADS)

Nakamura, Daisuke; Tasaki, Ryohei; Fujiwara, Yuki; Nagasaki, Fumiaki; Higashihata, Mitsuhiro; Ikenoue, Hiroshi; Okada, Tatsuo

2017-03-01

ZnO nano/microstructures have attracted much attention as building blocks for optoelectronic devices because of their high crystalline quality and unique structures. We have succeeded in synthesizing ZnO microspherical crystals by a simple atmospheric laser ablation method, and demonstrated ultraviolet whispering-gallery-mode lasing from the spheres. In the microsphere synthesis process, molten droplets formed into spherical shapes by surface tension, and crystalized during ejection from the ablation spot. In this study, we observed the generation of ZnO microspheres by high-speed camera. Now we are trying to control and manipulate the microspheres using a vortex beam.

Tops as building blocks for G 2 manifolds

NASA Astrophysics Data System (ADS)

Braun, Andreas P.

2017-10-01

A large number of examples of compact G 2 manifolds, relevant to supersymmetric compactifications of M-Theory to four dimensions, can be constructed by forming a twisted connected sum of two building blocks times a circle. These building blocks, which are appropriate K3-fibred threefolds, are shown to have a natural and elegant construction in terms of tops, which parallels the construction of Calabi-Yau manifolds via reflexive polytopes. In particular, this enables us to prove combinatorial formulas for the Hodge numbers and other relevant topological data.

Origami-inspired building block and parametric design for mechanical metamaterials

NASA Astrophysics Data System (ADS)

Jiang, Wei; Ma, Hua; Feng, Mingde; Yan, Leilei; Wang, Jiafu; Wang, Jun; Qu, Shaobo

2016-08-01

An origami-based building block of mechanical metamaterials is proposed and explained by introducing a mechanism model based on its geometry. According to our model, this origami mechanism supports response to uniaxial tension that depends on structure parameters. Hence, its mechanical properties can be tunable by adjusting the structure parameters. Experiments for poly lactic acid (PLA) samples were carried out, and the results are in good agreement with those of finite element analysis (FEA). This work may be useful for designing building blocks of mechanical metamaterials or other complex mechanical structures.

Large space erectable structures - building block structures study

NASA Technical Reports Server (NTRS)

Armstrong, W. H.; Skoumal, D. E.; Straayer, J. W.

1977-01-01

A modular planar truss structure and a long slender boom concept identified as building block approaches to construction of large spacecraft configurations are described. The concepts are compatible in weight and volume goals with the Space Transportation System, use standard structural units, and represent high on-orbit productivity in terms of structural area or beam length. Results of structural trade studies involving static and dynamic analyses of a single module and rigid body deployment analyses to assess kinetics and kinematics of automatic deployment of the building block modules are presented.

Field Trial of an Aerosol-Based Enclosure Sealing Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harrington, Curtis; Springer, David

2015-09-01

This report presents the results from several demonstrations of a new method for sealing building envelope air leaks using an aerosol sealing process developed by the Western Cooling Efficiency Center at UC Davis. The process involves pressurizing a building while applying an aerosol sealant to the interior. As air escapes through leaks in the building envelope, the aerosol particles are transported to the leaks where they collect and form a seal that blocks the leak. Standard blower door technology is used to facilitate the building pressurization, which allows the installer to track the sealing progress during the installation and automaticallymore » verify the final building tightness. Each aerosol envelope sealing installation was performed after drywall was installed and taped, and the process did not appear to interrupt the construction schedule or interfere with other trades working in the homes. The labor needed to physically seal bulk air leaks in typical construction will not be replaced by this technology. However, this technology is capable of bringing the air leakage of a building that was built with standard construction techniques and HERS-verified sealing down to levels that would meet DOE Zero Energy Ready Homes program requirements. When a developer is striving to meet a tighter envelope leakage specification, this technology could greatly reduce the cost to achieve that goal by providing a simple and relatively low cost method for reducing the air leakage of a building envelope with little to no change in their common building practices.« less

Spatial Characteristics of Small Green Spaces' Mitigating Effects on Microscopic Urban Heat Islands

NASA Astrophysics Data System (ADS)

Park, J.; Lee, D. K.; Jeong, W.; Kim, J. H.; Huh, K. Y.

2015-12-01

The purpose of the study is to find small greens' disposition, types and sizes to reduce air temperature effectively in urban blocks. The research sites were six high developed blocks in Seoul, Korea. Air temperature was measured with mobile loggers in clear daytime during summer, from August to September, at screen level. Also the measurement repeated over three times a day during three days by walking and circulating around the experimental blocks and the control blocks at the same time. By analyzing spatial characteristics, the averaged air temperatures were classified with three spaces, sunny spaces, building-shaded spaces and small green spaces by using Kruskal-Wallis Test; and small green spaces in 6 blocks were classified into their outward forms, polygonal or linear and single or mixed. The polygonal and mixed types of small green spaces mitigated averaged air temperature of each block which they belonged with a simple linear regression model with adjusted R2 = 0.90**. As the area and volume of these types increased, the effect of air temperature reduction (ΔT; Air temperature difference between sunny space and green space in a block) also increased in a linear relationship. The experimental range of this research is 100m2 ~ 2,000m2 of area, and 1,000m3 ~ 10,000m3 of volume of small green space. As a result, more than 300m2 and 2,300m3 of polygonal green spaces with mixed vegetation is required to lower 1°C; 650m2 and 5,000m3 of them to lower 2°C; about 2,000m2 and about 10,000m3 of them to lower 4°C air temperature reduction in an urban block.

View of the southwest guard tower, cell blocks seven and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

View of the southwest guard tower, cell blocks seven and eight, administration building west tower, and Fairmount Avenue, looking from the administration building facing west - Eastern State Penitentiary, 2125 Fairmount Avenue, Philadelphia, Philadelphia County, PA

Synthesis of most polyene natural product motifs using just 12 building blocks and one coupling reaction.

PubMed

Woerly, Eric M; Roy, Jahnabi; Burke, Martin D

2014-06-01

The inherent modularity of polypeptides, oligonucleotides and oligosaccharides has been harnessed to achieve generalized synthesis platforms. Importantly, like these other targets, most small-molecule natural products are biosynthesized via iterative coupling of bifunctional building blocks. This suggests that many small molecules also possess inherent modularity commensurate with systematic building block-based construction. Supporting this hypothesis, here we report that the polyene motifs found in >75% of all known polyene natural products can be synthesized using just 12 building blocks and one coupling reaction. Using the same general retrosynthetic algorithm and reaction conditions, this platform enabled both the synthesis of a wide range of polyene frameworks that covered all of this natural-product chemical space and the first total syntheses of the polyene natural products asnipyrone B, physarigin A and neurosporaxanthin b-D-glucopyranoside. Collectively, these results suggest the potential for a more generalized approach to making small molecules in the laboratory.

Synthesis of most polyene natural product motifs using just 12 building blocks and one coupling reaction

NASA Astrophysics Data System (ADS)

Woerly, Eric M.; Roy, Jahnabi; Burke, Martin D.

2014-06-01

The inherent modularity of polypeptides, oligonucleotides and oligosaccharides has been harnessed to achieve generalized synthesis platforms. Importantly, like these other targets, most small-molecule natural products are biosynthesized via iterative coupling of bifunctional building blocks. This suggests that many small molecules also possess inherent modularity commensurate with systematic building block-based construction. Supporting this hypothesis, here we report that the polyene motifs found in >75% of all known polyene natural products can be synthesized using just 12 building blocks and one coupling reaction. Using the same general retrosynthetic algorithm and reaction conditions, this platform enabled both the synthesis of a wide range of polyene frameworks that covered all of this natural-product chemical space and the first total syntheses of the polyene natural products asnipyrone B, physarigin A and neurosporaxanthin β-D-glucopyranoside. Collectively, these results suggest the potential for a more generalized approach to making small molecules in the laboratory.

Expanding the biomass derived chemical space

PubMed Central

Brun, Nicolas; Hesemann, Peter

2017-01-01

Biorefinery aims at the conversion of biomass and renewable feedstocks into fuels and platform chemicals, in analogy to conventional oil refinery. In the past years, the scientific community has defined a number of primary building blocks that can be obtained by direct biomass decomposition. However, the large potential of this “renewable chemical space” to contribute to the generation of value added bio-active compounds and materials still remains unexplored. In general, biomass derived building blocks feature a diverse range of chemical functionalities. In order to be integrated into value-added compounds, they require additional functionalization and/or covalent modification thereby generating secondary building blocks. The latter can be thus regarded as functional components of bio-active molecules or materials and represent an expansion of the renewable chemical space. This perspective highlights the most recent developments and opportunities for the synthesis of secondary biomass derived building blocks and their application to the preparation of value added products. PMID:28959397

SKIRT: The design of a suite of input models for Monte Carlo radiative transfer simulations

NASA Astrophysics Data System (ADS)

Baes, M.; Camps, P.

2015-09-01

The Monte Carlo method is the most popular technique to perform radiative transfer simulations in a general 3D geometry. The algorithms behind and acceleration techniques for Monte Carlo radiative transfer are discussed extensively in the literature, and many different Monte Carlo codes are publicly available. On the contrary, the design of a suite of components that can be used for the distribution of sources and sinks in radiative transfer codes has received very little attention. The availability of such models, with different degrees of complexity, has many benefits. For example, they can serve as toy models to test new physical ingredients, or as parameterised models for inverse radiative transfer fitting. For 3D Monte Carlo codes, this requires algorithms to efficiently generate random positions from 3D density distributions. We describe the design of a flexible suite of components for the Monte Carlo radiative transfer code SKIRT. The design is based on a combination of basic building blocks (which can be either analytical toy models or numerical models defined on grids or a set of particles) and the extensive use of decorators that combine and alter these building blocks to more complex structures. For a number of decorators, e.g. those that add spiral structure or clumpiness, we provide a detailed description of the algorithms that can be used to generate random positions. Advantages of this decorator-based design include code transparency, the avoidance of code duplication, and an increase in code maintainability. Moreover, since decorators can be chained without problems, very complex models can easily be constructed out of simple building blocks. Finally, based on a number of test simulations, we demonstrate that our design using customised random position generators is superior to a simpler design based on a generic black-box random position generator.

Rational design of monocrystalline (InP)(y)Ge(5-2y)/Ge/Si(100) semiconductors: synthesis and optical properties.

PubMed

Sims, Patrick E; Chizmeshya, Andrew V G; Jiang, Liying; Beeler, Richard T; Poweleit, Christian D; Gallagher, James; Smith, David J; Menéndez, José; Kouvetakis, John

2013-08-21

In this work, we extend our strategy previously developed to synthesize functional, crystalline Si(5-2y)(AlX)y {X = N,P,As} semiconductors to a new class of Ge-III-V hybrid compounds, leading to the creation of (InP)(y)Ge(5-2y) analogues. The compounds are grown directly on Ge-buffered Si(100) substrates using gas source MBE by tuning the interaction between Ge-based P(GeH3)3 precursors and In atoms to yield nanoscale "In-P-Ge3" building blocks, which then confer their molecular structure and composition to form the target solids via complete elimination of H2. The collateral production of reactive germylene (GeH2), via partial decomposition of P(GeH3)3, is achieved by simple adjustment of the deposition conditions, leading to controlled Ge enrichment of the solid product relative to the stoichiometric InPGe3 composition. High resolution XRD, XTEM, EDX, and RBS indicate that the resultant monocrystalline (InP)(y)Ge(5-2y) alloys with y = 0.3-0.7 are tetragonally strained and fully coherent with the substrate and possess a cubic diamond-like structure. Molecular and solid-state ab initio density functional theory (DFT) simulations support the viability of "In-P-Ge3" building-block assembly of the proposed crystal structures, which consist of a Ge parent crystal in which the P atoms form a third-nearest-neighbor sublattice and "In-P" dimers are oriented to exclude energetically unfavorable In-In bonding. The observed InP concentration dependence of the lattice constant is closely reproduced by DFT simulation of these model structures. Raman spectroscopy and ellipsometry are also consistent with the "In-P-Ge3" building-block interpretation of the crystal structure, while the observation of photoluminescence suggests that (InP)(y)Ge(5-2y) may have important optoelectronic applications.

Interfacial growth of large-area single-layer metal-organic framework nanosheets

PubMed Central

Makiura, Rie; Konovalov, Oleg

2013-01-01

The air/liquid interface is an excellent platform to assemble two-dimensional (2D) sheets of materials by enhancing spontaneous organizational features of the building components and encouraging large length scale in-plane growth. We have grown 2D molecularly-thin crystalline metal-organic-framework (MOF) nanosheets composed of porphyrin building units and metal-ion joints (NAFS-13) under operationally simple ambient conditions at the air/liquid interface. In-situ synchrotron X-ray diffraction studies of the formation process performed directly at the interface were employed to optimize the NAFS-13 growth protocol leading to the development of a post-injection method –post-injection of the metal connectors into the water subphase on whose surface the molecular building blocks are pre-oriented– which allowed us to achieve the formation of large-surface area morphologically-uniform preferentially-oriented single-layer nanosheets. The growth of such large-size high-quality sheets is of interest for the understanding of the fundamental physical/chemical properties associated with ultra-thin sheet-shaped materials and the realization of their use in applications. PMID:23974345

A VLSI decomposition of the deBruijn graph

NASA Technical Reports Server (NTRS)

Collins, O.; Dolinar, S.; Mceliece, R.; Pollara, F.

1990-01-01

A new Viterbi decoder for convolutional codes with constraint lengths up to 15, called the Big Viterbi Decoder, is under development for the Deep Space Network. It will be demonstrated by decoding data from the Galileo spacecraft, which has a rate 1/4, constraint-length 15 convolutional encoder on board. Here, the mathematical theory underlying the design of the very-large-scale-integrated (VLSI) chips that are being used to build this decoder is explained. The deBruijn graph B sub n describes the topology of a fully parallel, rate 1/v, constraint length n+2 Viterbi decoder, and it is shown that B sub n can be built by appropriately wiring together (i.e., connecting together with extra edges) many isomorphic copies of a fixed graph called a B sub n building block. The efficiency of such a building block is defined as the fraction of the edges in B sub n that are present in the copies of the building block. It is shown, among other things, that for any alpha less than 1, there exists a graph G which is a B sub n building block of efficiency greater than alpha for all sufficiently large n. These results are illustrated by describing a special hierarchical family of deBruijn building blocks, which has led to the design of the gate-array chips being used in the Big Viterbi Decoder.

Fracture mechanics life analytical methods verification testing

NASA Technical Reports Server (NTRS)

Favenesi, J. A.; Clemmons, T. G.; Lambert, T. J.

1994-01-01

Verification and validation of the basic information capabilities in NASCRAC has been completed. The basic information includes computation of K versus a, J versus a, and crack opening area versus a. These quantities represent building blocks which NASCRAC uses in its other computations such as fatigue crack life and tearing instability. Several methods were used to verify and validate the basic information capabilities. The simple configurations such as the compact tension specimen and a crack in a finite plate were verified and validated versus handbook solutions for simple loads. For general loads using weight functions, offline integration using standard FORTRAN routines was performed. For more complicated configurations such as corner cracks and semielliptical cracks, NASCRAC solutions were verified and validated versus published results and finite element analyses. A few minor problems were identified in the basic information capabilities of the simple configurations. In the more complicated configurations, significant differences between NASCRAC and reference solutions were observed because NASCRAC calculates its solutions as averaged values across the entire crack front whereas the reference solutions were computed for a single point.

Synapse fits neuron: joint reduction by model inversion.

PubMed

van der Scheer, H T; Doelman, A

2017-08-01

In this paper, we introduce a novel simplification method for dealing with physical systems that can be thought to consist of two subsystems connected in series, such as a neuron and a synapse. The aim of our method is to help find a simple, yet convincing model of the full cascade-connected system, assuming that a satisfactory model of one of the subsystems, e.g., the neuron, is already given. Our method allows us to validate a candidate model of the full cascade against data at a finer scale. In our main example, we apply our method to part of the squid's giant fiber system. We first postulate a simple, hypothetical model of cell-to-cell signaling based on the squid's escape response. Then, given a FitzHugh-type neuron model, we derive the verifiable model of the squid giant synapse that this hypothesis implies. We show that the derived synapse model accurately reproduces synaptic recordings, hence lending support to the postulated, simple model of cell-to-cell signaling, which thus, in turn, can be used as a basic building block for network models.

A Working Model of Protein Synthesis Using Lego(TM) Building Blocks.

ERIC Educational Resources Information Center

Templin, Mark A.; Fetters, Marcia K.

2002-01-01

Uses Lego building blocks to improve the effectiveness of teaching about protein synthesis. Provides diagrams and pictures for a 2-3 day student activity. Discusses mRNA, transfer RNA, and a protein synthesis model. (MVL)

Enantiopure heterobimetallic single-chain magnets from the chiral Ru(III) building block.

PubMed

Ru, Jing; Gao, Feng; Wu, Tao; Yao, Min-Xia; Li, Yi-Zhi; Zuo, Jing-Lin

2014-01-21

A pair of one-dimensional enantiomers based on the versatile chiral dicyanoruthenate(III) building block have been synthesized and they are chiral single-chain magnets with the effective spin-reversal barrier of 28.2 K.

Systems thinking in practice: the current status of the six WHO building blocks for health system strengthening in three BHOMA intervention districts of Zambia: a baseline qualitative study

PubMed Central

2013-01-01

Background The primary bottleneck to achieving the MDGs in low-income countries is health systems that are too fragile to deliver the volume and quality of services to those in need. Strong and effective health systems are increasingly considered a prerequisite to reducing the disease burden and to achieving the health MDGs. Zambia is one of the countries that are lagging behind in achieving millennium development targets. Several barriers have been identified as hindering the progress towards health related millennium development goals. Designing an intervention that addresses these barriers was crucial and so the Better Health Outcomes through Mentorship (BHOMA) project was designed to address the challenges in the Zambia’s MOH using a system wide approach. We applied systems thinking approach to describe the baseline status of the Six WHO building blocks for health system strengthening. Methods A qualitative study was conducted looking at the status of the Six WHO building blocks for health systems strengthening in three BHOMA districts. We conducted Focus group discussions with community members and In-depth Interviews with key informants. Data was analyzed using Nvivo version 9. Results The study showed that building block specific weaknesses had cross cutting effect in other health system building blocks which is an essential element of systems thinking. Challenges noted in service delivery were linked to human resources, medical supplies, information flow, governance and finance building blocks either directly or indirectly. Several barriers were identified as hindering access to health services by the local communities. These included supply side barriers: Shortage of qualified health workers, bad staff attitude, poor relationships between community and health staff, long waiting time, confidentiality and the gender of health workers. Demand side barriers: Long distance to health facility, cost of transport and cultural practices. Participating communities seemed to lack the capacity to hold health workers accountable for the drugs and services. Conclusion The study has shown that building block specific weaknesses had cross cutting effect in other health system building blocks. These linkages emphasised the need to use system wide approaches in assessing the performance of health system strengthening interventions. PMID:23902601

Précis of Simple heuristics that make us smart.

PubMed

Todd, P M; Gigerenzer, G

2000-10-01

How can anyone be rational in a world where knowledge is limited, time is pressing, and deep thought is often an unattainable luxury? Traditional models of unbounded rationality and optimization in cognitive science, economics, and animal behavior have tended to view decision-makers as possessing supernatural powers of reason, limitless knowledge, and endless time. But understanding decisions in the real world requires a more psychologically plausible notion of bounded rationality. In Simple heuristics that make us smart (Gigerenzer et al. 1999), we explore fast and frugal heuristics--simple rules in the mind's adaptive toolbox for making decisions with realistic mental resources. These heuristics can enable both living organisms and artificial systems to make smart choices quickly and with a minimum of information by exploiting the way that information is structured in particular environments. In this précis, we show how simple building blocks that control information search, stop search, and make decisions can be put together to form classes of heuristics, including: ignorance-based and one-reason decision making for choice, elimination models for categorization, and satisficing heuristics for sequential search. These simple heuristics perform comparably to more complex algorithms, particularly when generalizing to new data--that is, simplicity leads to robustness. We present evidence regarding when people use simple heuristics and describe the challenges to be addressed by this research program.

Building block diode laser concept for high brightness laser output in the kW range and its applications

NASA Astrophysics Data System (ADS)

Ferrario, Fabio; Fritsche, Haro; Grohe, Andreas; Hagen, Thomas; Kern, Holger; Koch, Ralf; Kruschke, Bastian; Reich, Axel; Sanftleben, Dennis; Steger, Ronny; Wallendorf, Till; Gries, Wolfgang

2016-03-01

The modular concept of DirectPhotonics laser systems is a big advantage regarding its manufacturability, serviceability as well as reproducibility. By sticking to identical base components an economic production allows to serve as many applications as possible while keeping the product variations minimal. The modular laser design is based on single emitters and various combining technics. In a first step we accept a reduction of the very high brightness of the single emitters by vertical stacking several diodes in fast axis. This can be theoretically done until the combined fast axis beam quality is on a comparable level as the individual diodes slow axis beam quality without loosing overall beam performance after fiber coupling. Those stacked individual emitters can be wavelength stabilized by an external resonator, providing the very same feedback to each of those laser diodes which leads to an output power of about 100 W with BPP of <3.5 mm*mrad (FA) and <5 mm*mrad (SA). In the next steps, further power scaling is accomplished by polarization and wavelength multiplexing yielding high optical efficiencies of more than 80% and resulting in a building block module with about 500 W launched into a 100 μm fiber with 0.15 NA. Higher power levels can be achieved by stacking those building blocks using the very same dense spectral combing technique up to multi kW Systems without further reduction of the BPP. The 500 W building blocks are consequently designed in a way that they feature a high flexibility with regard to their emitting wavelength bandwidth. Therefore, new wavelengths can be implemented by only exchanging parts and without any additional change of the production process. This design principal theoretically offers the option to adapt the wavelength of those blocks to any applications, from UV, visible into the far IR as long as there are any diodes commercially available. This opens numerous additional applications like laser pumping, scientific applications, materials processing such as cutting and welding of copper aluminum or steel and also medical application. Typical operating at wavelengths in the 9XX nm range, these systems are designed for and mainly used in cutting and welding applications, but adapted wavelength ranges such as 793 nm and 1530 nm are also offered. Around 15XX nm the diodes are already successfully used for resonant pumping of Erbium lasers [1]. Furthermore, the fully integrated electronic concept allows addressing further applications, as due to short lead lengths it is capable of generating very short μs pulses up to cw mode operation by simple software commands.

Dendronized Metal Nanoparticles-Self-Organizing Building Blocks for the Design of New Functional Materials

DTIC Science & Technology

2016-04-01

characterization has just started.       The hybrids that we have synthesized are based on plasmonic gold and  silver   nanoparticles  (NPs) but  the concept  is...AFRL-AFOSR-UK-TR-2016-0010 Dendronized metal nanoparticles - self-organizing building blocks for the design of new functional materials Bertrand...2015 4. TITLE AND SUBTITLE Dendronized metal nanoparticles - self-organizing building blocks for the design of new functional materials 5a. CONTRACT

A mixed molecular building block strategy for the design of nested polyhedron metal-organic frameworks.

PubMed

Tian, Dan; Chen, Qiang; Li, Yue; Zhang, Ying-Hui; Chang, Ze; Bu, Xian-He

2014-01-13

A mixed molecular building block (MBB) strategy for the synthesis of double-walled cage-based porous metal-organic frameworks (MOFs) is presented. By means of this method, two isostructural porous MOFs built from unprecedented double-walled metal-organic octahedron were obtained by introducing two size-matching C3 -symmetric molecular building blocks with different rigidities. With their unique framework structures, these MOFs provide, to the best of our knowledge, the first examples of double-walled octahedron-based MOFs. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Three dimensional Origami-based metamaterial

NASA Astrophysics Data System (ADS)

Kamrava, Soroush; Mousanezhad, Davood; Ebrahimi, Hamid; Ghosh, Ranajay; Vaziri, Ashkan; High Performance Materials; Structures Labratory Team

We present a novel cellular metamaterial constructed from Origami building blocks based on Miura-ori fold. The proposed cellular metamaterial exhibits unusual properties some of which stemming from the inherent properties of its Origami building blocks, and others manifesting due to its unique geometrical construction and architecture. These properties include foldability with two fully-folded configurations, auxeticity (i.e., negative Poisson's ratio), bistability, and self-locking of Origami building blocks to construct load-bearing cellular metamaterials. The kinematics and force response of the cellular metamaterial during folding were studied to investigate the underlying mechanisms resulting in its unique properties using analytical modeling and experiments.

EarthCube GeoLink: Semantics and Linked Data for the Geosciences

NASA Astrophysics Data System (ADS)

Arko, R. A.; Carbotte, S. M.; Chandler, C. L.; Cheatham, M.; Fils, D.; Hitzler, P.; Janowicz, K.; Ji, P.; Jones, M. B.; Krisnadhi, A.; Lehnert, K. A.; Mickle, A.; Narock, T.; O'Brien, M.; Raymond, L. M.; Schildhauer, M.; Shepherd, A.; Wiebe, P. H.

2015-12-01

The NSF EarthCube initiative is building next-generation cyberinfrastructure to aid geoscientists in collecting, accessing, analyzing, sharing, and visualizing their data and knowledge. The EarthCube GeoLink Building Block project focuses on a specific set of software protocols and vocabularies, often characterized as the Semantic Web and "Linked Data", to publish data online in a way that is easily discoverable, accessible, and interoperable. GeoLink brings together specialists from the computer science, geoscience, and library science domains, and includes data from a network of NSF-funded repositories that support scientific studies in marine geology, marine ecosystems, biogeochemistry, and paleoclimatology. We are working collaboratively with closely-related Building Block projects including EarthCollab and CINERGI, and solicit feedback from RCN projects including Cyberinfrastructure for Paleogeosciences (C4P) and iSamples. GeoLink has developed a modular ontology that describes essential geoscience research concepts; published data from seven collections (to date) on the Web as geospatially-enabled Linked Data using this ontology; matched and mapped data between collections using shared identifiers for investigators, repositories, datasets, funding awards, platforms, research cruises, physical specimens, and gazetteer features; and aggregated the results in a shared knowledgebase that can be queried via a standard SPARQL endpoint. Client applications have been built around the knowledgebase, including a Web/map-based data browser using the Leaflet JavaScript library and a simple query service using the OpenSearch format. Future development will include extending and refining the GeoLink ontology, adding content from additional repositories, developing semi-automated algorithms to enhance metadata, and further work on client applications.

Seismic Safety Of Simple Masonry Buildings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guadagnuolo, Mariateresa; Faella, Giuseppe

2008-07-08

Several masonry buildings comply with the rules for simple buildings provided by seismic codes. For these buildings explicit safety verifications are not compulsory if specific code rules are fulfilled. In fact it is assumed that their fulfilment ensures a suitable seismic behaviour of buildings and thus adequate safety under earthquakes. Italian and European seismic codes differ in the requirements for simple masonry buildings, mostly concerning the building typology, the building geometry and the acceleration at site. Obviously, a wide percentage of buildings assumed simple by codes should satisfy the numerical safety verification, so that no confusion and uncertainty have tomore » be given rise to designers who must use the codes. This paper aims at evaluating the seismic response of some simple unreinforced masonry buildings that comply with the provisions of the new Italian seismic code. Two-story buildings, having different geometry, are analysed and results from nonlinear static analyses performed by varying the acceleration at site are presented and discussed. Indications on the congruence between code rules and results of numerical analyses performed according to the code itself are supplied and, in this context, the obtained result can provide a contribution for improving the seismic code requirements.« less

Building America Case Study: Field Trial of an Aerosol-Based Enclosure Sealing Technology, Clovis, California

DOE Office of Scientific and Technical Information (OSTI.GOV)

This report presents the results from several demonstrations of a new method for sealing building envelope air leaks using an aerosol sealing process developed by the Western Cooling Efficiency Center at UC Davis. The process involves pressurizing a building while applying an aerosol sealant to the interior. As air escapes through leaks in the building envelope, the aerosol particles are transported to the leaks where they collect and form a seal that blocks the leak. Standard blower door technology is used to facilitate the building pressurization, which allows the installer to track the sealing progress during the installation and automaticallymore » verify the final building tightness. Each aerosol envelope sealing installation was performed after drywall was installed and taped, and the process did not appear to interrupt the construction schedule or interfere with other trades working in the homes. The labor needed to physically seal bulk air leaks in typical construction will not be replaced by this technology. However, this technology is capable of bringing the air leakage of a building that was built with standard construction techniques and HERS-verified sealing down to levels that would meet DOE Zero Energy Ready Homes program requirements. When a developer is striving to meet a tighter envelope leakage specification, this technology could greatly reduce the cost to achieve that goal by providing a simple and relatively low cost method for reducing the air leakage of a building envelope with little to no change in their common building practices.« less

PERTS: A Prototyping Environment for Real-Time Systems

NASA Technical Reports Server (NTRS)

Liu, Jane W. S.; Lin, Kwei-Jay; Liu, C. L.

1991-01-01

We discuss an ongoing project to build a Prototyping Environment for Real-Time Systems, called PERTS. PERTS is a unique prototyping environment in that it has (1) tools and performance models for the analysis and evaluation of real-time prototype systems, (2) building blocks for flexible real-time programs and the support system software, (3) basic building blocks of distributed and intelligent real time applications, and (4) an execution environment. PERTS will make the recent and future theoretical advances in real-time system design and engineering readily usable to practitioners. In particular, it will provide an environment for the use and evaluation of new design approaches, for experimentation with alternative system building blocks and for the analysis and performance profiling of prototype real-time systems.

Transportable Payload Operations Control Center reusable software: Building blocks for quality ground data systems

NASA Technical Reports Server (NTRS)

Mahmot, Ron; Koslosky, John T.; Beach, Edward; Schwarz, Barbara

1994-01-01

The Mission Operations Division (MOD) at Goddard Space Flight Center builds Mission Operations Centers which are used by Flight Operations Teams to monitor and control satellites. Reducing system life cycle costs through software reuse has always been a priority of the MOD. The MOD's Transportable Payload Operations Control Center development team established an extensive library of 14 subsystems with over 100,000 delivered source instructions of reusable, generic software components. Nine TPOCC-based control centers to date support 11 satellites and achieved an average software reuse level of more than 75 percent. This paper shares experiences of how the TPOCC building blocks were developed and how building block developer's, mission development teams, and users are all part of the process.

Convergence to Diagonal Form of Block Jacobi-type Processes

NASA Astrophysics Data System (ADS)

Hari, Vjeran

2008-09-01

The main result of recent research on convergence to diagonal form of block Jacobi-type processes is presented. For this purpose, all notions needed to describe the result are introduced. In particular, elementary block transformation matrices, simple and non-simple algorithms, block pivot strategies together with the appropriate equivalence relations are defined. The general block Jacobi-type process considered here can be specialized to take the form of almost any known Jacobi-type method for solving the ordinary or the generalized matrix eigenvalue and singular value problems. The assumptions used in the result are satisfied by many concrete methods.

A Novel Latin Hypercube Algorithm via Translational Propagation

PubMed Central

Pan, Guang; Ye, Pengcheng

2014-01-01

Metamodels have been widely used in engineering design to facilitate analysis and optimization of complex systems that involve computationally expensive simulation programs. The accuracy of metamodels is directly related to the experimental designs used. Optimal Latin hypercube designs are frequently used and have been shown to have good space-filling and projective properties. However, the high cost in constructing them limits their use. In this paper, a methodology for creating novel Latin hypercube designs via translational propagation and successive local enumeration algorithm (TPSLE) is developed without using formal optimization. TPSLE algorithm is based on the inspiration that a near optimal Latin Hypercube design can be constructed by a simple initial block with a few points generated by algorithm SLE as a building block. In fact, TPSLE algorithm offers a balanced trade-off between the efficiency and sampling performance. The proposed algorithm is compared to two existing algorithms and is found to be much more efficient in terms of the computation time and has acceptable space-filling and projective properties. PMID:25276844

Hydration effects on the electronic properties of eumelanin building blocks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Assis Oliveira, Leonardo Bruno; Departamento de Física - CEPAE, Universidade Federal de Goiás, 74690-900 Goiânia, GO; Escola de Ciências Exatas e da Computação, Pontifícia Universidade Católica de Goiás, 74605-010 Goiânia, GO

2016-08-28

Theoretical results for the electronic properties of eumelanin building blocks in the gas phase and water are presented. The building blocks presently investigated include the monomeric species DHI (5,6-dihydroxyindole) or hydroquinone (HQ), DHICA (5,6-dihydroxyindole-2-carboxylic acid), indolequinone (IQ), quinone methide (MQ), two covalently bonded dimers [HM ≡ HQ + MQ and IM ≡ IQ + MQ], and two tetramers [HMIM ≡ HQ + IM, IMIM ≡ IM + IM]. The electronic properties in water were determined by carrying out sequential Monte Carlo/time dependent density functional theory calculations. The results illustrate the role played by hydrogen bonding and electrostatic interactions in themore » electronic properties of eumelanin building blocks in a polar environment. In water, the dipole moments of monomeric species are significantly increased ([54–79]%) relative to their gas phase values. Recently, it has been proposed that the observed enhancement of the higher-energy absorption intensity in eumelanin can be explained by excitonic coupling among eumelanin protomolecules [C.-T. Chen et al., Nat. Commun. 5, 3859 (2014)]. Here, we are providing evidence that for DHICA, IQ, and HMIM, the electronic absorption toward the higher-energy end of the spectrum ([180–220] nm) is enhanced by long-range Coulombic interactions with the water environment. It was verified that by superposing the absorption spectra of different eumelanin building blocks corresponding to the monomers, dimers, and tetramers in liquid water, the behaviour of the experimental spectrum, which is characterised by a nearly monotonic decay from the ultraviolet to the infrared, is qualitatively reproduced. This result is in keeping with a “chemical disorder model,” where the broadband absorption of eumelanin pigments is determined by the superposition of the spectra associated with the monomeric and oligomeric building blocks.« less

Hydration effects on the electronic properties of eumelanin building blocks.

PubMed

Assis Oliveira, Leonardo Bruno; L Fonseca, Tertius; Costa Cabral, Benedito J; Coutinho, Kaline; Canuto, Sylvio

2016-08-28

Theoretical results for the electronic properties of eumelanin building blocks in the gas phase and water are presented. The building blocks presently investigated include the monomeric species DHI (5,6-dihydroxyindole) or hydroquinone (HQ), DHICA (5,6-dihydroxyindole-2-carboxylic acid), indolequinone (IQ), quinone methide (MQ), two covalently bonded dimers [HM ≡ HQ + MQ and IM ≡ IQ + MQ], and two tetramers [HMIM ≡ HQ + IM, IMIM ≡ IM + IM]. The electronic properties in water were determined by carrying out sequential Monte Carlo/time dependent density functional theory calculations. The results illustrate the role played by hydrogen bonding and electrostatic interactions in the electronic properties of eumelanin building blocks in a polar environment. In water, the dipole moments of monomeric species are significantly increased ([54-79]%) relative to their gas phase values. Recently, it has been proposed that the observed enhancement of the higher-energy absorption intensity in eumelanin can be explained by excitonic coupling among eumelanin protomolecules [C.-T. Chen et al., Nat. Commun. 5, 3859 (2014)]. Here, we are providing evidence that for DHICA, IQ, and HMIM, the electronic absorption toward the higher-energy end of the spectrum ([180-220] nm) is enhanced by long-range Coulombic interactions with the water environment. It was verified that by superposing the absorption spectra of different eumelanin building blocks corresponding to the monomers, dimers, and tetramers in liquid water, the behaviour of the experimental spectrum, which is characterised by a nearly monotonic decay from the ultraviolet to the infrared, is qualitatively reproduced. This result is in keeping with a "chemical disorder model," where the broadband absorption of eumelanin pigments is determined by the superposition of the spectra associated with the monomeric and oligomeric building blocks.

Hydration effects on the electronic properties of eumelanin building blocks

NASA Astrophysics Data System (ADS)

Assis Oliveira, Leonardo Bruno; L. Fonseca, Tertius; Costa Cabral, Benedito J.; Coutinho, Kaline; Canuto, Sylvio

2016-08-01

Theoretical results for the electronic properties of eumelanin building blocks in the gas phase and water are presented. The building blocks presently investigated include the monomeric species DHI (5,6-dihydroxyindole) or hydroquinone (HQ), DHICA (5,6-dihydroxyindole-2-carboxylic acid), indolequinone (IQ), quinone methide (MQ), two covalently bonded dimers [HM ≡ HQ + MQ and IM ≡ IQ + MQ], and two tetramers [HMIM ≡ HQ + IM, IMIM ≡ IM + IM]. The electronic properties in water were determined by carrying out sequential Monte Carlo/time dependent density functional theory calculations. The results illustrate the role played by hydrogen bonding and electrostatic interactions in the electronic properties of eumelanin building blocks in a polar environment. In water, the dipole moments of monomeric species are significantly increased ([54-79]%) relative to their gas phase values. Recently, it has been proposed that the observed enhancement of the higher-energy absorption intensity in eumelanin can be explained by excitonic coupling among eumelanin protomolecules [C.-T. Chen et al., Nat. Commun. 5, 3859 (2014)]. Here, we are providing evidence that for DHICA, IQ, and HMIM, the electronic absorption toward the higher-energy end of the spectrum ([180-220] nm) is enhanced by long-range Coulombic interactions with the water environment. It was verified that by superposing the absorption spectra of different eumelanin building blocks corresponding to the monomers, dimers, and tetramers in liquid water, the behaviour of the experimental spectrum, which is characterised by a nearly monotonic decay from the ultraviolet to the infrared, is qualitatively reproduced. This result is in keeping with a "chemical disorder model," where the broadband absorption of eumelanin pigments is determined by the superposition of the spectra associated with the monomeric and oligomeric building blocks.

Movement planning reflects skill level and age changes in toddlers

PubMed Central

Chen, Yu-ping; Keen, Rachel; Rosander, Kerstin; von Hofsten, Claes

2010-01-01

Kinematic measures of children’s reaching were found to reflect stable differences in skill level for planning for future actions. Thirty-five toddlers (18–21 months) were engaged in building block towers (precise task) and in placing blocks into an open container (imprecise task). Sixteen children were re-tested on the same tasks a year later. Longer deceleration as the hand approached the block for pickup was found in the tower task compared to the imprecise task, indicating planning for the second movement. More skillful toddlers who could build high towers had a longer deceleration phase when placing blocks on the tower than toddlers who built low towers. Kinematic differences between the groups remained a year later when all children could build high towers. PMID:21077868

Real World of Industrial Chemistry: Ethylene: The Organic Chemical Industry's Most Important Building Block.

ERIC Educational Resources Information Center

Fernelius, W. Conrad, Ed.; And Others

1979-01-01

The value of ethylene, as the organic chemical industry's most important building block, is discussed. The discussion focuses on the source of ethylene, its various forms and functions, and the ways in which the forms are made. (SA)

Two integrator loop quadrature oscillators: A review.

PubMed

Soliman, Ahmed M

2013-01-01

A review of the two integrator loop oscillator circuits providing two quadrature sinusoidal output voltages is given. All the circuits considered employ the minimum number of capacitors namely two except one circuit which uses three capacitors. The circuits considered are classified to four different classes. The first class includes floating capacitors and floating resistors and the active building blocks realizing these circuits are the Op Amp or the OTRA. The second class employs grounded capacitors and includes floating resistors and the active building blocks realizing these circuits are the DCVC or the unity gain cells or the CFOA. The third class employs grounded capacitors and grounded resistors and the active building blocks realizing these circuits are the CCII. The fourth class employs grounded capacitors and no resistors and the active building blocks realizing these circuits are the TA. Transformation methods showing the generation of different classes from each other is given in details and this is one of the main objectives of this paper.

Toward Generalization of Iterative Small Molecule Synthesis

PubMed Central

Lehmann, Jonathan W.; Blair, Daniel J.; Burke, Martin D.

2018-01-01

Small molecules have extensive untapped potential to benefit society, but access to this potential is too often restricted by limitations inherent to the customized approach currently used to synthesize this class of chemical matter. In contrast, the “building block approach”, i.e., generalized iterative assembly of interchangeable parts, has now proven to be a highly efficient and flexible way to construct things ranging all the way from skyscrapers to macromolecules to artificial intelligence algorithms. The structural redundancy found in many small molecules suggests that they possess a similar capacity for generalized building block-based construction. It is also encouraging that many customized iterative synthesis methods have been developed that improve access to specific classes of small molecules. There has also been substantial recent progress toward the iterative assembly of many different types of small molecules, including complex natural products, pharmaceuticals, biological probes, and materials, using common building blocks and coupling chemistry. Collectively, these advances suggest that a generalized building block approach for small molecule synthesis may be within reach. PMID:29696152

Structure to function: Spider silk and human collagen

NASA Astrophysics Data System (ADS)

Rabotyagova, Olena S.

Nature has the ability to assemble a variety of simple molecules into complex functional structures with diverse properties. Collagens, silks and muscles fibers are some examples of fibrous proteins with self-assembling properties. One of the great challenges facing Science is to mimic these designs in Nature to find a way to construct molecules that are capable of organizing into functional supra-structures by self-assembly. In order to do so, a construction kit consisting of molecular building blocks along with a complete understanding on how to form functional materials is required. In this current research, the focus is on spider silk and collagen as fibrous protein-based biopolymers that can shed light on how to generate nanostructures through the complex process of self-assembly. Spider silk in fiber form offers a unique combination of high elasticity, toughness, and mechanical strength, along with biological compatibility and biodegrability. Spider silk is an example of a natural block copolymer, in which hydrophobic and hydrophilic blocks are linked together generating polymers that organize into functional materials with extraordinary properties. Since silks resemble synthetic block copolymer systems, we adopted the principles of block copolymer design from the synthetic polymer literature to build block copolymers based on spider silk sequences. Moreover, we consider spider silk to be an important model with which to study the relationships between structure and properties in our system. Thus, the first part of this work was dedicated to a novel family of spider silk block copolymers, where we generated a new family of functional spider silk-like block copolymers through recombinant DNA technology. To provide fundamental insight into relationships between peptide primary sequence, block composition, and block length and observed morphological and structural features, we used these bioengineered spider silk block copolymers to study secondary structure, morphological features and assembly. Aside from fundamental perspectives, we anticipate that these results will provide a blueprint for the design of precise materials for a range of potential applications such as controlled release devices, functional coatings, components of tissue regeneration materials and environmentally friendly polymers in future studies. In the second part of this work, human collagen type I was studied as another representative of the family of fibrous proteins. Collagen type I is the most abundant extracellular matrix protein in the human body, providing the basis for tissue structure and directing cellular functions. Collagen has a complex structural hierarchy, organized at different length scales, including the characteristic triple helical feature. In the present study we assessed the relationship between collagen structure (native vs. denatured) and sensitivity to UV radiation with a focus on changes in the primary structure, conformation, microstructure and material properties. Free radical reactions are involved in collagen degradation and a mechanism for UV-induced collagen degradation related to structure was proposed. The results from this study demonstrated the role of collagen supramolecular organization (triple helix) in the context of the effects of electromagnetic radiation on extracellular matrices. Owing to the fact that both silks and collagens are proteins that have found widespread interest for biomaterial related needs, we anticipate that the current studies will serve as a foundation for future biomaterial designs with controlled properties. Furthermore, fundamental insight into self-assembly and environmentally-2mediated degradation, will build a foundation for fundamental understanding of the remodeling and functions of these types of fibrous proteins in vivo and in vitro. This type of insight is essential for many areas of scientific inquiry, from drug delivery, to scaffolds for tissue engineering, and to the stability of materials in space.

Diversity-Oriented Approaches to Polycyclics and Bioinspired Molecules via the Diels-Alder Strategy: Green Chemistry, Synthetic Economy, and Beyond.

PubMed

Kotha, Sambasivarao; Chavan, Arjun S; Goyal, Deepti

2015-05-11

We describe diverse approaches to various dienes and their utilization in the Diels-Alder reaction to produce a variety of polycycles. The dienes covered here are prepared by simple alkylation reaction or via the Claisen rearrangement or by enyne metathesis of alkyne or enyne building blocks. Here, we have also included the Diels-Alder chemistry of dendralenes, a higher analog of cross-conjugated dienes. The present article is inclusive of o-xylylene derivatives that are generated in situ starting with benzosultine or benzosulfone derivatives. The Diels-Alder reaction of these dienes with various dienophiles gave diverse polycyclic systems and biologically important targets.

Room temperature ferromagnetism in a phthalocyanine based carbon material

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honda, Z., E-mail: honda@fms.saitama-u.ac.jp; Sato, K.; Sakai, M.

2014-02-07

We report on a simple method to fabricate a magnetic carbon material that contains nitrogen-coordinated transition metals and has a large magnetic moment. Highly chlorinated iron phthalocyanine was used as building blocks and potassium as a coupling reagent to uniformly disperse nitrogen-coordinated iron atoms on the phthalocyanine based carbon material. The iron phthalocyanine based carbon material exhibits ferromagnetic properties at room temperature and the ferromagnetic phase transition occurs at T{sub c} = 490 ± 10 K. Transmission electron microscopy observation, X-ray diffraction analysis, and the temperature dependence of magnetization suggest that the phthalocyanine molecules form three-dimensional random networks in the iron phthalocyanine based carbon material.

Passion fruit-like nano-architectures: a general synthesis route

NASA Astrophysics Data System (ADS)

Cassano, D.; David, J.; Luin, S.; Voliani, V.

2017-03-01

Noble metal nanostructures have demonstrated a number of intriguing features for both medicine and catalysis. However, accumulation issues have prevented their clinical translation, while their use in catalysis has shown serious efficiency and stability hurdles. Here we introduce a simple and robust synthetic protocol for passion fruit-like nano-architectures composed by a silica shell embedding polymeric arrays of ultrasmall noble metal nanoparticles. These nano-architectures show interesting features for both oncology and catalysis. They avoid the issue of persistence in organism thanks to their fast biodegradation in renal clearable building blocks. Furthermore, their calcination results in yolk-shell structures composed by naked metal or alloy nanospheres shielded from aggregation by a silica shell.

Optical reversible programmable Boolean logic unit.

PubMed

Chattopadhyay, Tanay

2012-07-20

Computing with reversibility is the only way to avoid dissipation of energy associated with bit erase. So, a reversible microprocessor is required for future computing. In this paper, a design of a simple all-optical reversible programmable processor is proposed using a polarizing beam splitter, liquid crystal-phase spatial light modulators, a half-wave plate, and plane mirrors. This circuit can perform 16 logical operations according to three programming inputs. Also, inputs can be easily recovered from the outputs. It is named the "reversible programmable Boolean logic unit (RPBLU)." The logic unit is the basic building block of many complex computational operations. Hence the design is important in sense. Two orthogonally polarized lights are defined here as two logical states, respectively.

Protein nanoparticles are nontoxic, tuneable cell stressors.

PubMed

de Pinho Favaro, Marianna Teixeira; Sánchez-García, Laura; Sánchez-Chardi, Alejandro; Roldán, Mónica; Unzueta, Ugutz; Serna, Naroa; Cano-Garrido, Olivia; Azzoni, Adriano Rodrigues; Ferrer-Miralles, Neus; Villaverde, Antonio; Vázquez, Esther

2018-02-01

Nanoparticle-cell interactions can promote cell toxicity and stimulate particular behavioral patterns, but cell responses to protein nanomaterials have been poorly studied. By repositioning oligomerization domains in a simple, modular self-assembling protein platform, we have generated closely related but distinguishable homomeric nanoparticles. Composed by building blocks with modular domains arranged in different order, they share amino acid composition. These materials, once exposed to cultured cells, are differentially internalized in absence of toxicity and trigger distinctive cell adaptive responses, monitored by the emission of tubular filopodia and enhanced drug sensitivity. The capability to rapidly modulate such cell responses by conventional protein engineering reveals protein nanoparticles as tuneable, versatile and potent cell stressors for cell-targeted conditioning.

Nonequilibrium thermodynamics of the shear-transformation-zone model

NASA Astrophysics Data System (ADS)

Luo, Alan M.; Ã-ttinger, Hans Christian

2014-02-01

The shear-transformation-zone (STZ) model has been applied numerous times to describe the plastic deformation of different types of amorphous systems. We formulate this model within the general equation for nonequilibrium reversible-irreversible coupling (GENERIC) framework, thereby clarifying the thermodynamic structure of the constitutive equations and guaranteeing thermodynamic consistency. We propose natural, physically motivated forms for the building blocks of the GENERIC, which combine to produce a closed set of time evolution equations for the state variables, valid for any choice of free energy. We demonstrate an application of the new GENERIC-based model by choosing a simple form of the free energy. In addition, we present some numerical results and contrast those with the original STZ equations.

Salt-induced square prism Pd microtubes and their ethanol electrocatalysis properties

NASA Astrophysics Data System (ADS)

Jiang, Kunpeng; Ma, Shenghua; Wang, Yinan; Zhang, Ying; Han, Xiaojun

2017-05-01

The synthesis of square prism tubes are always challenging due to their thermo and dynamical instability. We demonstrated a simple method using Pd2+ doped PoPD oligomers as building blocks to assemble into 1D square prism metal-organic microtubes, which consists of cataphracted nanosheets on the surfaces. After high temperature treatment, the microtubes became square prism Pd tubes with a cross section size of 3 μm. The pure Pd microtubes showed excellent catalyzing activity towards the electro oxidation of ethanol. Their electrochemically active surface area is 48.2 m2 g-1, which indicates the square prism Pd tubes have great potential in the field of fuel cell.

Passion fruit-like nano-architectures: a general synthesis route

PubMed Central

Cassano, D.; David, J.; Luin, S.; Voliani, V.

2017-01-01

Noble metal nanostructures have demonstrated a number of intriguing features for both medicine and catalysis. However, accumulation issues have prevented their clinical translation, while their use in catalysis has shown serious efficiency and stability hurdles. Here we introduce a simple and robust synthetic protocol for passion fruit-like nano-architectures composed by a silica shell embedding polymeric arrays of ultrasmall noble metal nanoparticles. These nano-architectures show interesting features for both oncology and catalysis. They avoid the issue of persistence in organism thanks to their fast biodegradation in renal clearable building blocks. Furthermore, their calcination results in yolk-shell structures composed by naked metal or alloy nanospheres shielded from aggregation by a silica shell. PMID:28256565

Flaw tolerance promoted by dissipative deformation mechanisms between material building blocks

NASA Astrophysics Data System (ADS)

Verho, Tuukka; Buehler, Markus J.

2014-09-01

Novel high-performance composite materials often draw inspiration from natural materials such as bone or mollusc shells. A prime feature of such composites is that they are, like their natural counterparts, quasibrittle. They are tolerant to material flaws up to a certain characteristic flaw-tolerant size scale, exhibiting high strength and toughness, but start to behave in a brittle manner when sufficiently large flaws are present. Here, we establish that better flaw tolerance can be achieved by maximizing fracture toughness relative to the maximum elastic energy available in the material, and we demonstrate this concept with simple two-dimensional coarse-grained simulations where the transition from brittle to quasibrittle behaviour is examined.

The Vertex on a Strip

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashani-Poor, A.

2004-11-03

We demonstrate that for a broad class of local Calabi-Yau geometries built around a string of IP{sup 1}s--those whose toric diagrams are given by triangulations of a strip--we can derive simple rules, based on the topological vertex, for obtaining expressions for the topological string partition function in which the sums over Young tableaux have been performed. By allowing non-trivial tableaux on the external legs of the corresponding web diagrams, these strips can be used as building blocks for more general geometries. As applications of our result, we study the behavior of topological string amplitudes under flops, as well as checkmore » Nekrasov's conjecture in its most general form.« less

Highly selective deuteration of pharmaceutically relevant nitrogen-containing heterocycles: a flow chemistry approach.

PubMed

Ötvös, Sándor B; Mándity, István M; Fülöp, Ferenc

2011-08-01

A simple and efficient flow-based technique is reported for the catalytic deuteration of several model nitrogen-containing heterocyclic compounds which are important building blocks of pharmacologically active materials. A continuous flow reactor was used in combination with on-demand pressure-controlled electrolytic D(2) production. The D(2) source was D(2)O, the consumption of which was very low. The experimental set-up allows the fine-tuning of pressure, temperature, and flow rate so as to determine the optimal conditions for the deuteration reactions. The described procedure lacks most of the drawbacks of the conventional batch deuteration techniques, and additionally is highly selective and reproducible.

On-Chip Optical Nonreciprocity Using an Active Microcavity

PubMed Central

Jiang, Xiaoshun; Yang, Chao; Wu, Hongya; Hua, Shiyue; Chang, Long; Ding, Yang; Hua, Qian; Xiao, Min

2016-01-01

Optically nonreciprocal devices provide critical functionalities such as light isolation and circulation in integrated photonic circuits for optical communications and information processing, but have been difficult to achieve. By exploring gain-saturation nonlinearity, we demonstrate on-chip optical nonreciprocity with excellent isolation performance within telecommunication wavelengths using only one toroid microcavity. Compatible with current complementary metal-oxide-semiconductor process, our compact and simple scheme works for a very wide range of input power levels from ~10 microwatts down to ~10 nanowatts, and exhibits remarkable properties of one-way light transport with sufficiently low insertion loss. These superior features make our device become a promising critical building block indispensable for future integrated nanophotonic networks. PMID:27958356

A molybdenum disulfide/carbon nanotube heterogeneous complementary inverter.

PubMed

Huang, Jun; Somu, Sivasubramanian; Busnaina, Ahmed

2012-08-24

We report a simple, bottom-up/top-down approach for integrating drastically different nanoscale building blocks to form a heterogeneous complementary inverter circuit based on layered molybdenum disulfide and carbon nanotube (CNT) bundles. The fabricated CNT/MoS(2) inverter is composed of n-type molybdenum disulfide (MOS(2)) and p-type CNT transistors, with a high voltage gain of 1.3. The CNT channels are fabricated using directed assembly while the layered molybdenum disulfide channels are fabricated by mechanical exfoliation. This bottom-up fabrication approach for integrating various nanoscale elements with unique characteristics provides an alternative cost-effective methodology to complementary metal-oxide-semiconductors, laying the foundation for the realization of high performance logic circuits.

One-Pot Synthesis of N-Substituted β-Amino Alcohols from Aldehydes and Isocyanides.

PubMed

Cioc, Răzvan C; van der Niet, Daan J H; Janssen, Elwin; Ruijter, Eelco; Orru, Romano V A

2015-05-18

A practical two-stage one-pot synthesis of N-substituted β-amino alcohols using aldehydes and isocyanides as starting materials has been developed. This method features mild reaction conditions, broad scope, and general tolerance of functional groups. Based on a less common central carbon-carbon bond disconnection, this protocol complements traditional approaches that involve amines and various carbon electrophiles (epoxides, α-halo ketones, β-halohydrins). Medicinally relevant products can be prepared in a concise and efficient way from simple building blocks, as demonstrated in the synthesis of the antiasthma drug salbutamol. Upgrading the synthesis to an enantioselective variant is also feasible. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Building Quality Report Cards for Geriatric Care in The Netherlands: Using Concept Mapping to Identify the Appropriate "Building Blocks" from the Consumer's Perspective

ERIC Educational Resources Information Center

Groenewoud, A. Stef; van Exel, N. Job A.; Berg, Marc; Huijsman, Robbert

2008-01-01

Purpose: This article reports on a study to identify "building blocks" for quality report cards for geriatric care. Its aim is to present (a) the results of the study and (b) the innovative step-by-step approach that was developed to arrive at these results. Design and Methods: We used Concept Mapping/Structured Conceptualization to…

Building blocks for subleading helicity operators

DOE PAGES

Kolodrubetz, Daniel W.; Moult, Ian; Stewart, Iain W.

2016-05-24

On-shell helicity methods provide powerful tools for determining scattering amplitudes, which have a one-to-one correspondence with leading power helicity operators in the Soft-Collinear Effective Theory (SCET) away from singular regions of phase space. We show that helicity based operators are also useful for enumerating power suppressed SCET operators, which encode subleading amplitude information about singular limits. In particular, we present a complete set of scalar helicity building blocks that are valid for constructing operators at any order in the SCET power expansion. In conclusion, we also describe an interesting angular momentum selection rule that restricts how these building blocks canmore » be assembled.« less

Origami-based cellular metamaterial with auxetic, bistable, and self-locking properties

NASA Astrophysics Data System (ADS)

Kamrava, Soroush; Mousanezhad, Davood; Ebrahimi, Hamid; Ghosh, Ranajay; Vaziri, Ashkan

2017-04-01

We present a novel cellular metamaterial constructed from Origami building blocks based on Miura-ori fold. The proposed cellular metamaterial exhibits unusual properties some of which stemming from the inherent properties of its Origami building blocks, and others manifesting due to its unique geometrical construction and architecture. These properties include foldability with two fully-folded configurations, auxeticity (i.e., negative Poisson’s ratio), bistability, and self-locking of Origami building blocks to construct load-bearing cellular metamaterials. The kinematics and force response of the cellular metamaterial during folding were studied to investigate the underlying mechanisms resulting in its unique properties using analytical modeling and experiments.

Origami-based cellular metamaterial with auxetic, bistable, and self-locking properties

PubMed Central

Kamrava, Soroush; Mousanezhad, Davood; Ebrahimi, Hamid; Ghosh, Ranajay; Vaziri, Ashkan

2017-01-01

We present a novel cellular metamaterial constructed from Origami building blocks based on Miura-ori fold. The proposed cellular metamaterial exhibits unusual properties some of which stemming from the inherent properties of its Origami building blocks, and others manifesting due to its unique geometrical construction and architecture. These properties include foldability with two fully-folded configurations, auxeticity (i.e., negative Poisson’s ratio), bistability, and self-locking of Origami building blocks to construct load-bearing cellular metamaterials. The kinematics and force response of the cellular metamaterial during folding were studied to investigate the underlying mechanisms resulting in its unique properties using analytical modeling and experiments. PMID:28387345

Rapid formation of complexity in the total synthesis of natural products enabled by oxabicyclo[2.2.1]heptene building blocks.

PubMed

Schindler, Corinna S; Carreira, Erick M

2009-11-01

This critical review showcases examples of rapid formation of complexity in total syntheses starting from 7-oxabicyclo[2.2.1]hept-5-ene derivatives. An overview of methods allowing synthetic access to these building blocks is provided and their application in recently developed synthetic transformations to structurally complex systems is illustrated. In addition, the facile access to a novel oxabicyclo[2.2.1]heptene derived building block is presented which significantly enlarges the possibilities of previously known chemical transformations and is highlighted in the enantioselective route to the core of the banyaside and suomilide natural products (107 references).

Recent advances in synthesis of bacterial rare sugar building blocks and their applications.

PubMed

Emmadi, Madhu; Kulkarni, Suvarn S

2014-07-01

Covering: 1964 to 2013. Bacteria have unusual glycans on their surfaces which distinguish them from the host cells. These unique structures offer avenues for targeting bacteria with specific therapeutics and vaccine. However, these rare sugars are not accessible in acceptable purity and amounts by isolation from natural sources. Thus, procurement of orthogonally protected rare sugar building blocks through efficient chemical synthesis is regarded as a crucial step towards the development of glycoconjugate vaccines. This Highlight focuses on recent advances in the synthesis of the bacterial deoxy amino hexopyranoside building blocks and their application in constructing various biologically important bacterial O-glycans.

Ae2Sb2X4F2 (Ae = Sr, Ba): new members of the homologous series Ae2M(1+n)X(3+n)F2 designed from rock salt and fluorite 2D building blocks.

PubMed

Kabbour, Houria; Cario, Laurent

2006-03-20

We have designed new compounds within the homologous series Ae2F2M(1+n)X(3+n) (Ae = Sr, Ba; M = main group metal; n = integer) built up from the stacking of 2D building blocks of rock salt and fluorite types. By incrementally increasing the size of the rock salt 2D building blocks, we have obtained two new n = 1 members of this homologous series, namely, Sr2F2Sb2Se4 and Ba2F2Sb2Se4. We then succeeded in synthesizing these compounds using a high-temperature ceramic method. The structure refinements from the powder or single-crystal X-ray diffraction data confirmed presence of the expected alternating stacking of fluorite [Ae2F2] (Ae = Sr, Ba) and rock salt [Sb2Se4] 2D building blocks. However the Ba derivative shows a strong distortion of the [Sb2Se4] block and a concomitant change of the Sb atom coordination likely related to the lone-pair activity.

Probabilistic switching circuits in DNA

PubMed Central

Wilhelm, Daniel; Bruck, Jehoshua

2018-01-01

A natural feature of molecular systems is their inherent stochastic behavior. A fundamental challenge related to the programming of molecular information processing systems is to develop a circuit architecture that controls the stochastic states of individual molecular events. Here we present a systematic implementation of probabilistic switching circuits, using DNA strand displacement reactions. Exploiting the intrinsic stochasticity of molecular interactions, we developed a simple, unbiased DNA switch: An input signal strand binds to the switch and releases an output signal strand with probability one-half. Using this unbiased switch as a molecular building block, we designed DNA circuits that convert an input signal to an output signal with any desired probability. Further, this probability can be switched between 2n different values by simply varying the presence or absence of n distinct DNA molecules. We demonstrated several DNA circuits that have multiple layers and feedback, including a circuit that converts an input strand to an output strand with eight different probabilities, controlled by the combination of three DNA molecules. These circuits combine the advantages of digital and analog computation: They allow a small number of distinct input molecules to control a diverse signal range of output molecules, while keeping the inputs robust to noise and the outputs at precise values. Moreover, arbitrarily complex circuit behaviors can be implemented with just a single type of molecular building block. PMID:29339484

Simple Quaternary Ammonium Ions R4N + ( R= nPr, nBu, nPen) as Versatile Structure Directors for the Synthesis of Zeolite-Like, Heterobimetallic Cyanide Frameworks

NASA Astrophysics Data System (ADS)

Poll, Eyck-Michael; Samba, Sabine; Dieter Fischer, R.; Olbrich, Falk; Davies, Nicola A.; Avalle, Paolo; Apperley, David C.; Harris, Robin K.

2000-06-01

The preparation of three new examples of water insoluble host/guest assemblies of the general composition: [(R4N)(Me3Sn)2M(CN)6·zH2O] (R=n-propyl or n-pentyl, M=Fe or Co, 0≤z≤2) from likewise polymeric super-Prussian-blue derivatives [(Me3Sn)3M(CN)6] and aqueous (R4N)X solutions are reported. According to combined single-crystal X-ray (3a and 3a*: R=nPr, M=Co, z=2; 5b: R=nPen, M=Fe, z=0.5), powder X-ray diffraction (XRD), and multinuclear (13C, 15N, 59Co, 119Sn) CPMAS solid-state magnetic resonance studies, 3a and 3a* contain cis- and trans-isomeric [Co(CN)4(CNSnMe3OH2)2]- building blocks, respectively, which are held together exclusively by Sn←OH2···NC-Co hydrogen bonds. In striking contrast, the building blocks of 5b and 5a are infinite [M-CN-Sn-NC] chains. In all these assemblies, also significant C-H···NC hydrogen bonds between the encapsulated R4N+ guest ion and exclusively terminal cyanide ligands of the host seem to play a notable auxiliary role.

Conjugated polymers/semiconductor nanocrystals hybrid materials--preparation, electrical transport properties and applications.

PubMed

Reiss, Peter; Couderc, Elsa; De Girolamo, Julia; Pron, Adam

2011-02-01

This critical review discusses specific preparation and characterization methods applied to hybrid materials consisting of π-conjugated polymers (or oligomers) and semiconductor nanocrystals. These materials are of great importance in the quickly growing field of hybrid organic/inorganic electronics since they can serve as active components of photovoltaic cells, light emitting diodes, photodetectors and other devices. The electronic energy levels of the organic and inorganic components of the hybrid can be tuned individually and thin hybrid films can be processed using low cost solution based techniques. However, the interface between the hybrid components and the morphology of the hybrid directly influences the generation, separation and transport of charge carriers and those parameters are not easy to control. Therefore a large variety of different approaches for assembling the building blocks--conjugated polymers and semiconductor nanocrystals--has been developed. They range from their simple blending through various grafting procedures to methods exploiting specific non-covalent interactions between both components, induced by their tailor-made functionalization. In the first part of this review, we discuss the preparation of the building blocks (nanocrystals and polymers) and the strategies for their assembly into hybrid materials' thin films. In the second part, we focus on the charge carriers' generation and their transport within the hybrids. Finally, we summarize the performances of solar cells using conjugated polymer/semiconductor nanocrystals hybrids and give perspectives for future developments.

Total synthesis of a CD-ring: side-chain building block for preparing 17-epi-calcitriol derivatives from the Hajos-Parrish dione.

PubMed

Michalak, Karol; Wicha, Jerzy

2011-08-19

An efficient synthesis of the key building block for 17-epi-calctriol from the Hajos-Parrish dione involving a sequence of diastereoselective transformation of the azulene core and the side-chain construction is presented.

Multiresonant Composite Optical Nanoantennas by Out-of-plane Plasmonic Engineering.

PubMed

Song, Junyeob; Zhou, Wei

2018-06-27

Optical nanoantennas can concentrate light and enhance light-matter interactions in subwavelength domain, which is useful for photodetection, light emission, optical biosensing, and spectroscopy. However, conventional optical nanoantennas operating at a single wavelength band are not suitable for multiband applications. Here, we propose and exploit an out-of-plane plasmonic engineering strategy to design and create composite optical nanoantennas that can support multiple nanolocalized modes at different resonant wavelengths. These multiresonant composite nanoantennas are composed of vertically stacked building blocks of metal-insulator-metal loop nanoantennas. Studies of multiresonant composite nanoantennas demonstrate that the number of supported modes depends on the number of vertically stacked building blocks and the resonant wavelengths of individual modes are tunable by controlling the out-of-plane geometries of their building blocks. In addition, numerical studies show that the resonant wavelengths of individual modes in composite nanoantennas can deviate from the optical response of building blocks due to hybridization of magnetic modes in neighboring building blocks. Using Au nanohole arrays as deposition masks to fabricate arrays of multilayered composite nanoantennas, we experimentally demonstrate their multiresonant optical properties in good agreement with theory predictions. These studies show that out-of-plane engineered multiresonant composite nanoantennas can provide new opportunities for fundamental nanophotonics research and practical applications involving optical multiband operations, such as multiphoton process, broadband solar energy conversion, and wavelength-multiplexed optical system.

Branching patterns in leaf starches from Arabidopsis mutants deficient in diverse starch synthases.

PubMed

Zhu, Fan; Bertoft, Eric; Szydlowski, Nicolas; d'Hulst, Christophe; Seetharaman, Koushik

2015-01-12

This is the first report on the cluster structure of transitory starch from Arabidopsis leaves. In addition to wild type, the molecular structures of leaf starch from mutants deficient in starch synthases (SS) including single enzyme mutants ss1-, ss2-, or ss3-, and also double mutants ss1-ss2- and ss1-ss3- were characterized. The mutations resulted in increased amylose content. Clusters from whole starch were isolated by partial hydrolysis using α-amylase of Bacillus amyloliquefaciens. The clusters were then further hydrolyzed with concentrated α-amylase of B. amyloliquefaciens to produce building blocks (α-limit dextrins). Structures of the clusters and their building blocks were characterized by chromatography of samples before and after debranching treatment. While the mutations increased the size of clusters, the reasons were different as reflected by the composition of their unit chains and building blocks. In general, all mutants contained more of a-chains that preferentially increased the number of small building blocks with only two chains. The clusters of the double mutant ss1-ss3- were very large and possessed also more of large building blocks with four or more chains. The results from transitory starch are compared with those from agriculturally important crops in the context that to what extent the Arabidopsis can be a true biotechnological reflection for starch modifications through genetic means. Copyright © 2014 Elsevier Ltd. All rights reserved.

Alq3 nanorods: promising building blocks for optical devices.

PubMed

Chen, Wei; Peng, Qing; Li, Yadong

2008-07-17

Monodisperse Alq3 nanorods with hexagonal-prism-like morphology are produced via a facile, emulsion based synthesis route. The photoluminescence of individual nanorods differs from the bulk material. These nanorods are promising building blocks for novel optical devices. Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Racing to learn: statistical inference and learning in a single spiking neuron with adaptive kernels

PubMed Central

Afshar, Saeed; George, Libin; Tapson, Jonathan; van Schaik, André; Hamilton, Tara J.

2014-01-01

This paper describes the Synapto-dendritic Kernel Adapting Neuron (SKAN), a simple spiking neuron model that performs statistical inference and unsupervised learning of spatiotemporal spike patterns. SKAN is the first proposed neuron model to investigate the effects of dynamic synapto-dendritic kernels and demonstrate their computational power even at the single neuron scale. The rule-set defining the neuron is simple: there are no complex mathematical operations such as normalization, exponentiation or even multiplication. The functionalities of SKAN emerge from the real-time interaction of simple additive and binary processes. Like a biological neuron, SKAN is robust to signal and parameter noise, and can utilize both in its operations. At the network scale neurons are locked in a race with each other with the fastest neuron to spike effectively “hiding” its learnt pattern from its neighbors. The robustness to noise, high speed, and simple building blocks not only make SKAN an interesting neuron model in computational neuroscience, but also make it ideal for implementation in digital and analog neuromorphic systems which is demonstrated through an implementation in a Field Programmable Gate Array (FPGA). Matlab, Python, and Verilog implementations of SKAN are available at: http://www.uws.edu.au/bioelectronics_neuroscience/bens/reproducible_research. PMID:25505378

A simple structure wavelet transform circuit employing function link neural networks and SI filters

NASA Astrophysics Data System (ADS)

Mu, Li; Yigang, He

2016-12-01

Signal processing by means of analog circuits offers advantages from a power consumption viewpoint. Implementing wavelet transform (WT) using analog circuits is of great interest when low-power consumption becomes an important issue. In this article, a novel simple structure WT circuit in analog domain is presented by employing functional link neural network (FLNN) and switched-current (SI) filters. First, the wavelet base is approximated using FLNN algorithms for giving a filter transfer function that is suitable for simple structure WT circuit implementation. Next, the WT circuit is constructed with the wavelet filter bank, whose impulse response is the approximated wavelet and its dilations. The filter design that follows is based on a follow-the-leader feedback (FLF) structure with multiple output bilinear SI integrators and current mirrors as the main building blocks. SI filter is well suited for this application since the dilation constant across different scales of the transform can be precisely implemented and controlled by the clock frequency of the circuit with the same system architecture. Finally, to illustrate the design procedure, a seventh-order FLNN-approximated Gaussian wavelet is implemented as an example. Simulations have successfully verified that the designed simple structure WT circuit has low sensitivity, low-power consumption and litter effect to the imperfections.

Racing to learn: statistical inference and learning in a single spiking neuron with adaptive kernels.

PubMed

Afshar, Saeed; George, Libin; Tapson, Jonathan; van Schaik, André; Hamilton, Tara J

2014-01-01

This paper describes the Synapto-dendritic Kernel Adapting Neuron (SKAN), a simple spiking neuron model that performs statistical inference and unsupervised learning of spatiotemporal spike patterns. SKAN is the first proposed neuron model to investigate the effects of dynamic synapto-dendritic kernels and demonstrate their computational power even at the single neuron scale. The rule-set defining the neuron is simple: there are no complex mathematical operations such as normalization, exponentiation or even multiplication. The functionalities of SKAN emerge from the real-time interaction of simple additive and binary processes. Like a biological neuron, SKAN is robust to signal and parameter noise, and can utilize both in its operations. At the network scale neurons are locked in a race with each other with the fastest neuron to spike effectively "hiding" its learnt pattern from its neighbors. The robustness to noise, high speed, and simple building blocks not only make SKAN an interesting neuron model in computational neuroscience, but also make it ideal for implementation in digital and analog neuromorphic systems which is demonstrated through an implementation in a Field Programmable Gate Array (FPGA). Matlab, Python, and Verilog implementations of SKAN are available at: http://www.uws.edu.au/bioelectronics_neuroscience/bens/reproducible_research.

Forecasting Maintenance Shortcomings of a Planned Equipment Density Listing in Support of Expeditionary Missions

DTIC Science & Technology

2017-06-01

importantly, it examines the methodology used to build the class IX block embarked on ship prior to deployment. The class IX block is defined as a repository...compared to historical data to evaluate model and simulation outputs. This thesis provides recommendations on improving the methodology implemented in...improving the level of organic support available to deployed units. More importantly, it examines the methodology used to build the class IX block

π-Extended Isoindigo-Based Derivative: A Promising Electron-Deficient Building Block for Polymer Semiconductors.

PubMed

Xu, Long; Zhao, Zhiyuan; Xiao, Mingchao; Yang, Jie; Xiao, Jian; Yi, Zhengran; Wang, Shuai; Liu, Yunqi

2017-11-22

The exploration of novel electron-deficient building blocks is a key task for developing high-performance polymer semiconductors in organic thin-film transistors. In view of the situation of the lack of strong electron-deficient building blocks, we designed two novel π-extended isoindigo-based electron-deficient building blocks, IVI and F 4 IVI. Owing to the strong electron-deficient nature and the extended π-conjugated system of the two acceptor units, their copolymers, PIVI2T and PF 4 IVI2T, containing 2,2'-bithiophene donor units, are endowed with deep-lying highest occupied molecular orbital (HOMO)/lowest unoccupied molecular orbital (LUMO) energy levels and strong intermolecular interactions. In comparison to PIVI2T, the fluorinated PF 4 IVI2T exhibits stronger intra- and intermolecular interactions, lower HOMO/LUMO energy levels up to -5.74/-4.17 eV, and more ordered molecular packing with a smaller π-π stacking distance of up to 3.53 Å, resulting in an excellent ambipolar transporting behavior and a promising application in logic circuits for PF 4 IVI2T in ambient with hole and electron mobilities of up to 1.03 and 1.82 cm 2 V -1 s -1 , respectively. The results reveal that F 4 IVI is a promising and strong electron-deficient building unit to construct high-performance semiconducting polymers, which provides an insight into the structure-property relationships for the exploration and molecular engineering of excellent electron-deficient building blocks in the field of organic electronics.

Letter of intent for KM3NeT 2.0

NASA Astrophysics Data System (ADS)

Adrián-Martínez, S.; Ageron, M.; Aharonian, F.; Aiello, S.; Albert, A.; Ameli, F.; Anassontzis, E.; Andre, M.; Androulakis, G.; Anghinolfi, M.; Anton, G.; Ardid, M.; Avgitas, T.; Barbarino, G.; Barbarito, E.; Baret, B.; Barrios-Martí, J.; Belhorma, B.; Belias, A.; Berbee, E.; van den Berg, A.; Bertin, V.; Beurthey, S.; van Beveren, V.; Beverini, N.; Biagi, S.; Biagioni, A.; Billault, M.; Bondì, M.; Bormuth, R.; Bouhadef, B.; Bourlis, G.; Bourret, S.; Boutonnet, C.; Bouwhuis, M.; Bozza, C.; Bruijn, R.; Brunner, J.; Buis, E.; Busto, J.; Cacopardo, G.; Caillat, L.; Calamai, M.; Calvo, D.; Capone, A.; Caramete, L.; Cecchini, S.; Celli, S.; Champion, C.; Cherkaoui El Moursli, R.; Cherubini, S.; Chiarusi, T.; Circella, M.; Classen, L.; Cocimano, R.; Coelho, J. A. B.; Coleiro, A.; Colonges, S.; Coniglione, R.; Cordelli, M.; Cosquer, A.; Coyle, P.; Creusot, A.; Cuttone, G.; D'Amico, A.; De Bonis, G.; De Rosa, G.; De Sio, C.; Di Capua, F.; Di Palma, I.; Díaz García, A. F.; Distefano, C.; Donzaud, C.; Dornic, D.; Dorosti-Hasankiadeh, Q.; Drakopoulou, E.; Drouhin, D.; Drury, L.; Durocher, M.; Eberl, T.; Eichie, S.; van Eijk, D.; El Bojaddaini, I.; El Khayati, N.; Elsaesser, D.; Enzenhöfer, A.; Fassi, F.; Favali, P.; Fermani, P.; Ferrara, G.; Filippidis, C.; Frascadore, G.; Fusco, L. A.; Gal, T.; Galatà, S.; Garufi, F.; Gay, P.; Gebyehu, M.; Giordano, V.; Gizani, N.; Gracia, R.; Graf, K.; Grégoire, T.; Grella, G.; Habel, R.; Hallmann, S.; van Haren, H.; Harissopulos, S.; Heid, T.; Heijboer, A.; Heine, E.; Henry, S.; Hernández-Rey, J. J.; Hevinga, M.; Hofestädt, J.; Hugon, C. M. F.; Illuminati, G.; James, C. W.; Jansweijer, P.; Jongen, M.; de Jong, M.; Kadler, M.; Kalekin, O.; Kappes, A.; Katz, U. F.; Keller, P.; Kieft, G.; Kießling, D.; Koffeman, E. N.; Kooijman, P.; Kouchner, A.; Kulikovskiy, V.; Lahmann, R.; Lamare, P.; Leisos, A.; Leonora, E.; Clark, M. Lindsey; Liolios, A.; Llorens Alvarez, C. D.; Lo Presti, D.; Löhner, H.; Lonardo, A.; Lotze, M.; Loucatos, S.; Maccioni, E.; Mannheim, K.; Margiotta, A.; Marinelli, A.; Mariş, O.; Markou, C.; Martínez-Mora, J. A.; Martini, A.; Mele, R.; Melis, K. W.; Michael, T.; Migliozzi, P.; Migneco, E.; Mijakowski, P.; Miraglia, A.; Mollo, C. M.; Mongelli, M.; Morganti, M.; Moussa, A.; Musico, P.; Musumeci, M.; Navas, S.; Nicolau, C. A.; Olcina, I.; Olivetto, C.; Orlando, A.; Papaikonomou, A.; Papaleo, R.; Păvălaş, G. E.; Peek, H.; Pellegrino, C.; Perrina, C.; Pfutzner, M.; Piattelli, P.; Pikounis, K.; Poma, G. E.; Popa, V.; Pradier, T.; Pratolongo, F.; Pühlhofer, G.; Pulvirenti, S.; Quinn, L.; Racca, C.; Raffaelli, F.; Randazzo, N.; Rapidis, P.; Razis, P.; Real, D.; Resvanis, L.; Reubelt, J.; Riccobene, G.; Rossi, C.; Rovelli, A.; Saldaña, M.; Salvadori, I.; Samtleben, D. F. E.; Sánchez García, A.; Sánchez Losa, A.; Sanguineti, M.; Santangelo, A.; Santonocito, D.; Sapienza, P.; Schimmel, F.; Schmelling, J.; Sciacca, V.; Sedita, M.; Seitz, T.; Sgura, I.; Simeone, F.; Siotis, I.; Sipala, V.; Spisso, B.; Spurio, M.; Stavropoulos, G.; Steijger, J.; Stellacci, S. M.; Stransky, D.; Taiuti, M.; Tayalati, Y.; Tézier, D.; Theraube, S.; Thompson, L.; Timmer, P.; Tönnis, C.; Trasatti, L.; Trovato, A.; Tsirigotis, A.; Tzamarias, S.; Tzamariudaki, E.; Vallage, B.; Van Elewyck, V.; Vermeulen, J.; Vicini, P.; Viola, S.; Vivolo, D.; Volkert, M.; Voulgaris, G.; Wiggers, L.; Wilms, J.; de Wolf, E.; Zachariadou, K.; Zornoza, J. D.; Zúñiga, J.

2016-08-01

The main objectives of the KM3NeT Collaboration are (i) the discovery and subsequent observation of high-energy neutrino sources in the Universe and (ii) the determination of the mass hierarchy of neutrinos. These objectives are strongly motivated by two recent important discoveries, namely: (1) the high-energy astrophysical neutrino signal reported by IceCube and (2) the sizable contribution of electron neutrinos to the third neutrino mass eigenstate as reported by Daya Bay, Reno and others. To meet these objectives, the KM3NeT Collaboration plans to build a new Research Infrastructure consisting of a network of deep-sea neutrino telescopes in the Mediterranean Sea. A phased and distributed implementation is pursued which maximises the access to regional funds, the availability of human resources and the synergistic opportunities for the Earth and sea sciences community. Three suitable deep-sea sites are selected, namely off-shore Toulon (France), Capo Passero (Sicily, Italy) and Pylos (Peloponnese, Greece). The infrastructure will consist of three so-called building blocks. A building block comprises 115 strings, each string comprises 18 optical modules and each optical module comprises 31 photo-multiplier tubes. Each building block thus constitutes a three-dimensional array of photo sensors that can be used to detect the Cherenkov light produced by relativistic particles emerging from neutrino interactions. Two building blocks will be sparsely configured to fully explore the IceCube signal with similar instrumented volume, different methodology, improved resolution and complementary field of view, including the galactic plane. One building block will be densely configured to precisely measure atmospheric neutrino oscillations.

Programmable disorder in random DNA tilings

NASA Astrophysics Data System (ADS)

Tikhomirov, Grigory; Petersen, Philip; Qian, Lulu

2017-03-01

Scaling up the complexity and diversity of synthetic molecular structures will require strategies that exploit the inherent stochasticity of molecular systems in a controlled fashion. Here we demonstrate a framework for programming random DNA tilings and show how to control the properties of global patterns through simple, local rules. We constructed three general forms of planar network—random loops, mazes and trees—on the surface of self-assembled DNA origami arrays on the micrometre scale with nanometre resolution. Using simple molecular building blocks and robust experimental conditions, we demonstrate control of a wide range of properties of the random networks, including the branching rules, the growth directions, the proximity between adjacent networks and the size distribution. Much as combinatorial approaches for generating random one-dimensional chains of polymers have been used to revolutionize chemical synthesis and the selection of functional nucleic acids, our strategy extends these principles to random two-dimensional networks of molecules and creates new opportunities for fabricating more complex molecular devices that are organized by DNA nanostructures.

Correlation Imaging Reveals Specific Crowding Dynamics of Kinesin Motor Proteins

NASA Astrophysics Data System (ADS)

Miedema, Daniël M.; Kushwaha, Vandana S.; Denisov, Dmitry V.; Acar, Seyda; Nienhuis, Bernard; Peterman, Erwin J. G.; Schall, Peter

2017-10-01

Molecular motor proteins fulfill the critical function of transporting organelles and other building blocks along the biopolymer network of the cell's cytoskeleton, but crowding effects are believed to crucially affect this motor-driven transport due to motor interactions. Physical transport models, like the paradigmatic, totally asymmetric simple exclusion process (TASEP), have been used to predict these crowding effects based on simple exclusion interactions, but verifying them in experiments remains challenging. Here, we introduce a correlation imaging technique to precisely measure the motor density, velocity, and run length along filaments under crowding conditions, enabling us to elucidate the physical nature of crowding and test TASEP model predictions. Using the kinesin motor proteins kinesin-1 and OSM-3, we identify crowding effects in qualitative agreement with TASEP predictions, and we achieve excellent quantitative agreement by extending the model with motor-specific interaction ranges and crowding-dependent detachment probabilities. These results confirm the applicability of basic nonequilibrium models to the intracellular transport and highlight motor-specific strategies to deal with crowding.

UUI: Reusable Spatial Data Services in Unified User Interface at NASA GES DISC

NASA Technical Reports Server (NTRS)

Petrenko, Maksym; Hegde, Mahabaleshwa; Bryant, Keith; Pham, Long B.

2016-01-01

Unified User Interface (UUI) is a next-generation operational data access tool that has been developed at Goddard Earth Sciences Data and Information Services Center(GES DISC) to provide a simple, unified, and intuitive one-stop shop experience for the key data services available at GES DISC, including subsetting (Simple Subset Wizard -SSW), granule file search (Mirador), plotting (Giovanni), and other legacy spatial data services. UUI has been built based on a flexible infrastructure of reusable web services self-contained building blocks that can easily be plugged into spatial applications, including third-party clients or services, to easily enable new functionality as new datasets and services become available. In this presentation, we will discuss our experience in designing UUI services based on open industry standards. We will also explain how the resulting framework can be used for a rapid development, deployment, and integration of spatial data services, facilitating efficient access and dissemination of spatial data sets.

Determining Possible Building Blocks of the Earth and Mars

NASA Technical Reports Server (NTRS)

Burbine, T. H.; OBrien, K. M.

2004-01-01

One of the fundamental questions concerning planetary formation is exactly what material did the planets form from? All the planets in our solar system are believed to have formed out of material from the solar nebula. Chondritic meteorites appear to sample this primitive material. Chondritic meteorites are generally classified into 13 major groups, which have a variety of compositions. Detailed studies of possible building blocks of the terrestrial planets require samples that can be used to estimate the bulk chemistry of these bodies. This study will focus on trying to determine possible building blocks of Earth and Mars since samples of these two planets can be studied in detail in the laboratory.

OBSIFRAC: database-supported software for 3D modeling of rock mass fragmentation

NASA Astrophysics Data System (ADS)

Empereur-Mot, Luc; Villemin, Thierry

2003-03-01

Under stress, fractures in rock masses tend to form fully connected networks. The mass can thus be thought of as a 3D series of blocks produced by fragmentation processes. A numerical model has been developed that uses a relational database to describe such a mass. The model, which assumes the fractures to be plane, allows data from natural networks to test theories concerning fragmentation processes. In the model, blocks are bordered by faces that are composed of edges and vertices. A fracture can originate from a seed point, its orientation being controlled by the stress field specified by an orientation matrix. Alternatively, it can be generated from a discrete set of given orientations and positions. Both kinds of fracture can occur together in a model. From an original simple block, a given fracture produces two simple polyhedral blocks, and the original block becomes compound. Compound and simple blocks created throughout fragmentation are stored in the database. Several fragmentation processes have been studied. In one scenario, a constant proportion of blocks is fragmented at each step of the process. The resulting distribution appears to be fractal, although seed points are random in each fragmented block. In a second scenario, division affects only one random block at each stage of the process, and gives a Weibull volume distribution law. This software can be used for a large number of other applications.

MyGeoHub: A Collaborative Geospatial Research and Education Platform

NASA Astrophysics Data System (ADS)

Kalyanam, R.; Zhao, L.; Biehl, L. L.; Song, C. X.; Merwade, V.; Villoria, N.

2017-12-01

Scientific research is increasingly collaborative and globally distributed; research groups now rely on web-based scientific tools and data management systems to simplify their day-to-day collaborative workflows. However, such tools often lack seamless interfaces, requiring researchers to contend with manual data transfers, annotation and sharing. MyGeoHub is a web platform that supports out-of-the-box, seamless workflows involving data ingestion, metadata extraction, analysis, sharing and publication. MyGeoHub is built on the HUBzero cyberinfrastructure platform and adds general-purpose software building blocks (GABBs), for geospatial data management, visualization and analysis. A data management building block iData, processes geospatial files, extracting metadata for keyword and map-based search while enabling quick previews. iData is pervasive, allowing access through a web interface, scientific tools on MyGeoHub or even mobile field devices via a data service API. GABBs includes a Python map library as well as map widgets that in a few lines of code, generate complete geospatial visualization web interfaces for scientific tools. GABBs also includes powerful tools that can be used with no programming effort. The GeoBuilder tool provides an intuitive wizard for importing multi-variable, geo-located time series data (typical of sensor readings, GPS trackers) to build visualizations supporting data filtering and plotting. MyGeoHub has been used in tutorials at scientific conferences and educational activities for K-12 students. MyGeoHub is also constantly evolving; the recent addition of Jupyter and R Shiny notebook environments enable reproducible, richly interactive geospatial analyses and applications ranging from simple pre-processing to published tools. MyGeoHub is not a monolithic geospatial science gateway, instead it supports diverse needs ranging from just a feature-rich data management system, to complex scientific tools and workflows.

LEGO® Bricks as Building Blocks for Centimeter-Scale Biological Environments: The Case of Plants

PubMed Central

Lind, Kara R.; Sizmur, Tom; Benomar, Saida; Miller, Anthony; Cademartiri, Ludovico

2014-01-01

LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil. PMID:24963716

LEGO® bricks as building blocks for centimeter-scale biological environments: the case of plants.

PubMed

Lind, Kara R; Sizmur, Tom; Benomar, Saida; Miller, Anthony; Cademartiri, Ludovico

2014-01-01

LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil.

Building Blocks and Cognitive Building Blocks: Playing to Know the World Mathematically

ERIC Educational Resources Information Center

Sarama, Julie; Clements, Douglas H.

2009-01-01

The authors explore how children's play can support the development of the foundations of mathematics learning and how adults can support children's representation of--and thus the "mathematization" of--their play. The authors review research about the amount and nature of mathematics found in the free play of children. They briefly…

Trainer's Guide to Building Blocks for Teaching Preschoolers with Special Needs [CD-ROM

ERIC Educational Resources Information Center

Joseph, Gail E.; Sandall, Susan R.; Schwartz, Ilene S.

2010-01-01

An essential teaching companion for instructors of pre-K educators, this convenient CD-ROM is a vivid blueprint for effective inclusive education using the popular "Building Blocks" approach. Following the structure of the bestselling textbook, this comprehensive guide helps teacher educators provide effective instruction on the three types of…

1. NORTHWEST FRONT AND SOUTHWEST SIDE, SHOWING LOCATION OF BUILDING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. NORTHWEST FRONT AND SOUTHWEST SIDE, SHOWING LOCATION OF BUILDING 0520 WEST OF FIRING CONTOL BLOCK HOUSE (BLDG. 0545), BETWEEN SLED TRACK AND CAMERA ACCESS ROAD. - Edwards Air Force Base, South Base Sled Track, Observation Block House, Station "O" area, east end of Sled Track, Lancaster, Los Angeles County, CA

Building an Early Childhood Parent-Teacher Resource Center.

ERIC Educational Resources Information Center

Holloway, Mary A.

This manual is a guidebook to the development of the Project Enlightenment Parent-Teacher Resource Center and serves as a reference for the replication of this type of center in other communities. The manual consists of three chapters that are conceptualized as building blocks, because they are sequential, incremental, and independent. Block A…

Effects of a Preschool Mathematics Curriculum: Summative Research on the "Building Blocks" Project

ERIC Educational Resources Information Center

Clements, Douglas H.; Sarama, Julie

2007-01-01

This study evaluated the efficacy of a preschool mathematics program based on a comprehensive model of developing research-based software and print curricula. Building Blocks, funded by the National Science Foundation, is a curriculum development project focused on creating research-based, technology-enhanced mathematics materials for pre-K…

PBF Reactor Building (PER620). Detail of arrangement of highdensity blocks ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF Reactor Building (PER-620). Detail of arrangement of high-density blocks and other basement shielding. Date: February 1966. Ebasco Services 1205 PER/PBF 620-A-7. INEEL index no. 761-0620-00-205-123070 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

University Education in Ontario: Shared Goals & Building Blocks.

ERIC Educational Resources Information Center

Council of Ontario Universities, Toronto.

This brochure suggests five goals that are likely to be shared by the people of Ontario, their government, and the province's publicly funded universities for a strong university system, and identifies the building blocks and resource-related commitments that would enable Ontario universities to achieve these goals. The goals are: (1) all…

Stereoselective total synthesis of Oxylipin from open chain gluco-configured building block.

PubMed

Borkar, Santosh Ramdas; Aidhen, Indrapal Singh

2017-04-18

Total synthesis of naturally occurring Oxylipin has been achieved from open chain gluco-configured building block which is readily assembled from inexpensive and commercially available D-(+)-gluconolactone. Grignard reaction and Wittig olefination reactions are key steps for the requisite CC bond formation. Copyright © 2017. Published by Elsevier Ltd.

Patterning nonisometric origami in nematic elastomer sheets

NASA Astrophysics Data System (ADS)

Plucinsky, Paul; Kowalski, Benjamin A.; White, Timothy J.; Bhattacharya, Kaushik

Nematic elastomers dramatically change their shape in response to diverse stimuli including light and heat. In this paper, we provide a systematic framework for the design of complex three dimensional shapes through the actuation of heterogeneously patterned nematic elastomer sheets. These sheets are composed of \\textit{nonisometric origami} building blocks which, when appropriately linked together, can actuate into a diverse array of three dimensional faceted shapes. We demonstrate both theoretically and experimentally that: 1) the nonisometric origami building blocks actuate in the predicted manner, 2) the integration of multiple building blocks leads to complex multi-stable, yet predictable, shapes, 3) we can bias the actuation experimentally to obtain a desired complex shape amongst the multi-stable shapes. We then show that this experimentally realized functionality enables a rich possible design landscape for actuation using nematic elastomers. We highlight this landscape through theoretical examples, which utilize large arrays of these building blocks to realize a desired three dimensional origami shape. In combination, these results amount to an engineering design principle, which we hope will provide a template for the application of nematic elastomers to emerging technologies.

Structure of clusters and building blocks in amylopectin from African rice accessions.

PubMed

Gayin, Joseph; Abdel-Aal, El-Sayed M; Marcone, Massimo; Manful, John; Bertoft, Eric

2016-09-05

Enzymatic hydrolysis in combination with gel-permeation and anion-exchange chromatography techniques were employed to characterise the composition of clusters and building blocks of amylopectin from two African rice (Oryza glaberrima) accessions-IRGC 103759 and TOG 12440. The samples were compared with one Asian rice (Oryza sativa) sample (cv WITA 4) and one O. sativa×O. glaberrima cross (NERICA 4). The average DP of clusters from the African rice accessions (ARAs) was marginally larger (DP=83) than in WITA 4 (DP=81). However, regarding average number of chains, clusters from the ARAs represented both the smallest and largest clusters. Overall, the result suggested that the structure of clusters in TOG 12440 was dense with short chains and high degree of branching, whereas the situation was the opposite in NERICA 4. IRGC 103759 and WITA 4 possessed clusters with intermediate characteristics. The commonest type of building blocks in all samples was group 2 (single branched dextrins) representing 40.3-49.4% of the blocks, while groups 3-6 were found in successively lower numbers. The average number of building blocks in the clusters was significantly larger in NERICA 4 (5.8) and WITA 4 (5.7) than in IRGC 103759 and TOG 12440 (5.1 and 5.3, respectively). Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of nanoparticle shape on the morphology and properties of porous CdSe assemblies (aerogels).

PubMed

Yu, Hongtao; Brock, Stephanie L

2008-08-01

We demonstrate the effect of differently shaped CdSe nanoscale building blocks (dots, rods, branched nanoparticles, and hyperbranched nanoparticles) on the morphologies, surface characteristics, and optical properties of resultant porous CdSe nanostructured aerogels. Monolithic CdSe aerogels were produced by controlled oxidative removal of surface thiolate ligands from differently shaped CdSe nanoparticles to yield a wet gel, followed by CO(2) supercritical drying. The X-ray diffraction data show that the resultant CdSe aerogels maintain the crystalline phase of the building blocks without significant grain growth. However, the transmission electron microscopy images indicate that the morphology of CdSe aerogels changes from a colloid-type morphology to a polymer-type morphology when the building block changes from dot to rod or the branched nanoparticle. The morphology of the CdSe aerogel assembled from hyperbranched nanoparticles appears to be intermediate between the colloid-type and the polymer-type. Nitrogen physisorption measurements suggest that the surface areas and porosity are a direct function of the shape of the primary building blocks, with aerogels formed from rods or branched particles exhibiting the greatest surface areas (>200 m(2)/g) and those prepared from hyperbranched nanoparticles exhibiting the least (<100 m(2)/g). Band gap measurements and photoluminescence studies show that the as-prepared CdSe aerogels retain to a large extent the intrinsic quantum confinement of the differently shaped building blocks, despite being connected into a 3D network.

Effective Light Directed Assembly of Building Blocks with Microscale Control.

PubMed

Dinh, Ngoc-Duy; Luo, Rongcong; Christine, Maria Tankeh Asuncion; Lin, Weikang Nicholas; Shih, Wei-Chuan; Goh, James Cho-Hong; Chen, Chia-Hung

2017-06-01

Light-directed forces have been widely used to pattern micro/nanoscale objects with precise control, forming functional assemblies. However, a substantial laser intensity is required to generate sufficient optical gradient forces to move a small object in a certain direction, causing limited throughput for applications. A high-throughput light-directed assembly is demonstrated as a printing technology by introducing gold nanorods to induce thermal convection flows that move microparticles (diameter = 40 µm to several hundreds of micrometers) to specific light-guided locations, forming desired patterns. With the advantage of effective light-directed assembly, the microfluidic-fabricated monodispersed biocompatible microparticles are used as building blocks to construct a structured assembly (≈10 cm scale) in ≈2 min. The control with microscale precision is approached by changing the size of the laser light spot. After crosslinking assembly of building blocks, a novel soft material with wanted pattern is approached. To demonstrate its application, the mesenchymal stem-cell-seeded hydrogel microparticles are prepared as functional building blocks to construct scaffold-free tissues with desired structures. This light-directed fabrication method can be applied to integrate different building units, enabling the bottom-up formation of materials with precise control over their internal structure for bioprinting, tissue engineering, and advanced manufacturing. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

SynTrack: DNA Assembly Workflow Management (SynTrack) v2.0.1

DOE Office of Scientific and Technical Information (OSTI.GOV)

MENG, XIANWEI; SIMIRENKO, LISA

2016-12-01

SynTrack is a dynamic, workflow-driven data management system that tracks the DNA build process: Management of the hierarchical relationships of the DNA fragments; Monitoring of process tasks for the assembly of multiple DNA fragments into final constructs; Creations of vendor order forms with selectable building blocks. Organizing plate layouts barcodes for vendor/pcr/fusion/chewback/bioassay/glycerol/master plate maps (default/condensed); Creating or updating Pre-Assembly/Assembly process workflows with selected building blocks; Generating Echo pooling instructions based on plate maps; Tracking of building block orders, received and final assembled for delivering; Bulk updating of colony or PCR amplification information, fusion PCR and chewback results; Updating with QA/QCmore » outcome with .csv & .xlsx template files; Re-work assembly workflow enabled before and after sequencing validation; and Tracking of plate/well data changes and status updates and reporting of master plate status with QC outcomes.« less

Building Trades. Block II. Foundations.

ERIC Educational Resources Information Center

Texas A and M Univ., College Station. Vocational Instructional Services.

Twelve informational lessons and eleven manipulative lessons are provided on foundations as applied to the building trades. Informational lessons cover land measurements; blueprint reading; level instruments; building and site planning; building site preparation; laying out building lines; soil preparation and special evacuation; concrete forms;…

The Building Blocks of Digital Media Literacy: Socio-Material Participation and the Production of Media Knowledge

ERIC Educational Resources Information Center

Dezuanni, Michael

2015-01-01

This article outlines the knowledge and skills students develop when they engage in digital media production and analysis in school settings. The metaphor of "digital building blocks" is used to describe the material practices, conceptual understandings and production of knowledge that lead to the development of digital media literacy.…

Plumbing Specialist II & III, 3-22. Military Curriculum Materials for Vocational and Technical Education.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

These military-developed curriculum materials consist of a course description, course chart, plan of instruction, lesson plans, study guides, and workbooks for use in training plumbing specialists II and III. Covered in the course blocks are building waste systems and exterior and interior supply systems. Course block II, on building waste…

The Development of Logico-Mathematical Knowledge in a Block-Building Activity at Ages 1-4

ERIC Educational Resources Information Center

Kamii, Constance; Miyakawa, Yoko; Kato, Yasuhiko

2004-01-01

To study the developmental interrelationships among various aspects of logico-mathematical knowledge, 80 one- to 4-year-olds were individually asked to build "something tall" with 20 blocks. Percentages of new and significant behaviors increased with age and were analyzed in terms of the development of logico-mathematical relationships. It was…

Building Blocks of Contemporary HRD Research: A Citation Analysis on Human Resource Development Quarterly between 2007 and 2013

ERIC Educational Resources Information Center

Mehdiabadi, Amir Hedayati; Seo, Gaeun; Huang, Wenhao David; Han, Seung-hyun Caleb

2017-01-01

Human resource development is known to encapsulate a collection of social science disciplines including communications, psychology, and economics. Since these and other similar areas are the cornerstones of HRD, the changing nature of HRD demands constant reflections on the value and building blocks of contemporary HRD inquiries. This article…

Non-symbolic arithmetic in adults and young children.

PubMed

Barth, Hilary; La Mont, Kristen; Lipton, Jennifer; Dehaene, Stanislas; Kanwisher, Nancy; Spelke, Elizabeth

2006-01-01

Five experiments investigated whether adults and preschool children can perform simple arithmetic calculations on non-symbolic numerosities. Previous research has demonstrated that human adults, human infants, and non-human animals can process numerical quantities through approximate representations of their magnitudes. Here we consider whether these non-symbolic numerical representations might serve as a building block of uniquely human, learned mathematics. Both adults and children with no training in arithmetic successfully performed approximate arithmetic on large sets of elements. Success at these tasks did not depend on non-numerical continuous quantities, modality-specific quantity information, the adoption of alternative non-arithmetic strategies, or learned symbolic arithmetic knowledge. Abstract numerical quantity representations therefore are computationally functional and may provide a foundation for formal mathematics.

Gold glyconanoparticles: synthetic polyvalent ligands mimicking glycocalyx-like surfaces as tools for glycobiological studies.

PubMed

Barrientos, Africa G; de la Fuente, Jesús M; Rojas, Teresa C; Fernández, Asunción; Penadés, Soledad

2003-05-09

A simple and versatile methodology is described for tailoring sugar-functionalised gold nanoclusters (glyconanoparticles) that have 3D polyvalent carbohydrate display and globular shapes. This methodology allows the preparation of glyconanoparticles with biologically significant oligosaccharides as well as with differing carbohydrate density. Fluorescent glyconanoparticles have been also prepared for labelling cells in biological tests. The materials are water soluble, stable under physiological conditions and present an exceptional small core size. All of them have been characterised by (1)H NMR, UV and IR spectroscopy, TEM and elemental analysis. Their highly polyvalent network can mimic glycosphingolipid clustering and interactions at the plasma membrane, providing an controlled system for glycobiological studies. Furthermore, they are useful building blocks for the design of nanomaterials.

Catalytic Oxidative Carbonylation of Amino Moieties to Ureas, Oxamides, 2-Oxazolidinones, and Benzoxazolones.

PubMed

Mancuso, Raffaella; Raut, Dnyaneshwar S; Della Ca', Nicola; Fini, Francesco; Carfagna, Carla; Gabriele, Bartolo

2015-07-08

The direct syntheses of ureas, oxamides, 2-oxazolidinones, and benzoxazolones by the oxidative carbonylation of amines, β-amino alcohols, and 2-aminophenols allows us to obtain high value added molecules, which have a large number of important applications in several fields, from very simple building blocks. We have found that it is possible to perform these transformations using the PdI2 /KI catalytic system in an ionic liquid, such as 1-butyl-3-methylimidazolium tetrafluoroborate, as the solvent, the solvent/catalyst system can be recycled several times with only a slight loss of activity, and the product can be recovered easily by crystallization. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tick, Tock, Tick, Tock...

NASA Astrophysics Data System (ADS)

Evans, N. W.; Molloy, M.

2014-07-01

The Gaia dataset will require a huge leap forward in terms of modelling of the Milky Way. Two problems are highlighted here. First, models of the Galactic Bar remain primitive as compared to the Galactic Disk and Stellar Halo. Although Schwarzschild and N-body methods are useful, the future belongs to Made-to-Measure (M2M) models which have significant advantages in terms of storage and flexibility. Second, the Milky Way potential will need much better representation than hitherto. Most models still use very simple building blocks (Miyamoto-Nagai disks or Hernquist bulges) and these will not be fit for purpose in the Gaia Era. Expansions in terms of basis functions offer the possibility of incorporating cosmological information as priors, as well as mych greater adaptability.

Enantioselective oxidation of racemic lactic acid to D-lactic acid and pyruvic acid by Pseudomonas stutzeri SDM.

PubMed

Gao, Chao; Qiu, Jianhua; Li, Jingchen; Ma, Cuiqing; Tang, Hongzhi; Xu, Ping

2009-03-01

D-lactic acid and pyruvic acid are two important building block intermediates. Production of D-lactic acid and pyruvic acid from racemic lactic acid by biotransformation is economically interesting. Biocatalyst prepared from 9 g dry cell wt l(-1) of Pseudomonas stutzeri SDM could catalyze 45.00 g l(-1)DL-lactic acid into 25.23 g l(-1)D-lactic acid and 19.70 g l(-1) pyruvic acid in 10h. Using a simple ion exchange process, D-lactic acid and pyruvic acid were effectively separated from the biotransformation system. Co-production of d-lactic acid and pyruvic acid by enantioselective oxidation of racemic lactic acid is technically feasible.

Chemical composition of donor-acceptor complexes of hydroxyoxo(5,10,15,20-tetraphenylporphinato)molybdenum(V) with 3,5-dimethylpyrazole and equilibrium constants for their formation

NASA Astrophysics Data System (ADS)

Motorina, E. V.; Lomova, T. N.

2017-11-01

The results from a quantitative study of reactions between hydroxyoxo(5,10,15,20-tetraphenylporphinato)molybdenum(V) (O=Mo(OH)TPP) and 3,5-dimethylpyrazole, a biologically active base, in toluene are presented. The chemical structure and key parameters of intermediates and reaction products are determined by spectral means. The equilibrium constant ( K = 51.3 L/mol) is calculated and a full kinetic description of simple reactions that occur in this system during complex transformation is obtained. The prospect of using a mixed porphyrin-containing complex as a receptor for 3,5-dimethylpyrazole, a building block for alkaloids and pharmaceutical preparations, is substantiated.

A Natural Glycyrrhizic Acid-Tailored Light-Responsive Gelator.

PubMed

Fang, Heshu; Zhao, Xia; Lin, Yuan; Yang, Song; Hu, Jun

2018-05-04

The construction of stimuli-responsive materials by using naturally occurring molecules as building blocks has received increasing attention owing to their bioavailability, biocompatibility, and biodegradability. Herein, a symmetrical azobenzene-functionalized natural glycyrrhizic acid (trans-GAG) was synthesized and could form stable supramolecular gels in DMSO/H 2 O and MeOH/H 2 O. Owing to trans-cis isomerization, this gel exhibited typical light-responsive behavior that led to a reversible gel-sol transition accompanied by a variation in morphology and rheology. Additionally, this trans-GAG gel displayed a distinct injectable self-healing property and outstanding biocompatibility. This work provides a simple yet rational strategy to fabricate stimuli-responsive materials from naturally occurring, eco-friendly molecules. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

A biochemically semi-detailed model of auxin-mediated vein formation in plant leaves.

PubMed

Roussel, Marc R; Slingerland, Martin J

2012-09-01

We present here a model intended to capture the biochemistry of vein formation in plant leaves. The model consists of three modules. Two of these modules, those describing auxin signaling and transport in plant cells, are biochemically detailed. We couple these modules to a simple model for PIN (auxin efflux carrier) protein localization based on an extracellular auxin sensor. We study the single-cell responses of this combined model in order to verify proper functioning of the modeled biochemical network. We then assemble a multicellular model from the single-cell building blocks. We find that the model can, under some conditions, generate files of polarized cells, but not true veins. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Rapid trifluoromethylation and perfluoroalkylation of five-membered heterocycles by photoredox catalysis in continuous flow.

PubMed

Straathof, Natan J W; Gemoets, Hannes P L; Wang, Xiao; Schouten, Jaap C; Hessel, Volker; Noël, Timothy

2014-06-01

Trifluoromethylated and perfluoroalkylated heterocycles are important building blocks for the synthesis of numerous pharmaceutical products, agrochemicals and are widely applied in material sciences. To date, trifluoromethylated and perfluoroalkylated hetero-aromatic systems can be prepared utilizing visible light photoredox catalysis methodologies in batch. While several limitations are associated with these batch protocols, the application of microflow technology could greatly enhance and intensify these reactions. A simple and straightforward photocatalytic trifluoromethylation and perfluoroalkylation method has been developed in continuous microflow, using commercially available photocatalysts and microflow components. A selection of five-membered hetero-aromatics were successfully trifluoromethylated (12 examples) and perfluoroalkylated (5 examples) within several minutes (8-20 min). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Oxyfunctionalization of the Remote C-H Bonds of Aliphatic Amines by Decatungstate Photocatalysis.

PubMed

Schultz, Danielle M; Lévesque, François; DiRocco, Daniel A; Reibarkh, Mikhail; Ji, Yining; Joyce, Leo A; Dropinski, James F; Sheng, Huaming; Sherry, Benjamin D; Davies, Ian W

2017-11-27

Aliphatic amines, oxygenated at remote positions within the molecule, represent an important class of synthetic building blocks to which there are currently no direct means of access. Reported herein is an efficient and scalable solution that relies upon decatungstate photocatalysis under acidic conditions using either H 2 O 2 or O 2 as the terminal oxidant. By using these reaction conditions a series of simple and unbiased aliphatic amine starting materials can be oxidized to value-added ketone products. Lastly, NMR spectroscopy using in situ LED-irradiated samples was utilized to monitor the kinetics of the reaction, thus enabling direct translation of the reaction into flow. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Quantitative NMR Approach to Optimize the Formation of Chemical Building Blocks from Abundant Carbohydrates.

PubMed

Elliot, Samuel G; Tolborg, Søren; Sádaba, Irantzu; Taarning, Esben; Meier, Sebastian

2017-07-21

The future role of biomass-derived chemicals relies on the formation of diverse functional monomers in high yields from carbohydrates. Recently, it has become clear that a series of α-hydroxy acids, esters, and lactones can be formed from carbohydrates in alcohol and water solvents using tin-containing catalysts such as Sn-Beta. These compounds are potential building blocks for polyesters bearing additional olefin and alcohol functionalities. An NMR approach was used to identify, quantify, and optimize the formation of these building blocks in the Sn-Beta-catalyzed transformation of abundant carbohydrates. Record yields of the target molecules can be achieved by obstructing competing reactions through solvent selection. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comprehensive assessment of the efficiency of high-rise construction projects in the form of urban blocks

NASA Astrophysics Data System (ADS)

Orlov, Alexandr; Chubarkina, Irina

2018-03-01

The paper is dedicated to main modern trends in the area of high-rise construction. The classification of buildings and structures by height is given. Functional distribution by the height of buildings is presented. A review of positive and negative aspects of high-rise construction from the economic point of view is given. On the basis of the data obtained, it is proposed to build up residential microdistricts in the form of urban blocks. A plan of microdistricts development is presented. It takes into account urban blocks and includes their main characteristics. An economic and mathematical model was developed to carry out a comprehensive assessment of the effectiveness of high-rise construction projects.

Advances in metabolic pathway and strain engineering paving the way for sustainable production of chemical building blocks.

PubMed

Chen, Yun; Nielsen, Jens

2013-12-01

Bio-based production of chemical building blocks from renewable resources is an attractive alternative to petroleum-based platform chemicals. Metabolic pathway and strain engineering is the key element in constructing robust microbial chemical factories within the constraints of cost effective production. Here we discuss how the development of computational algorithms, novel modules and methods, omics-based techniques combined with modeling refinement are enabling reduction in development time and thus advance the field of industrial biotechnology. We further discuss how recent technological developments contribute to the development of novel cell factories for the production of the building block chemicals: adipic acid, succinic acid and 3-hydroxypropionic acid. Copyright © 2013 Elsevier Ltd. All rights reserved.

An Ap-Structure with Finslerian Flavor I:. the Principal Idea

NASA Astrophysics Data System (ADS)

Wanas, M. I.

A geometric structure (FAP-structure), having both absolute parallelism and Finsler properties, is constructed. The building blocks of this structure are assumed to be functions of position and direction. A nonlinear connection emerges naturally and is defined in terms of the building blocks of the structure. Two linear connections, one of Berwald type and the other of the Cartan type, are defined using the nonlinear connection of the FAP. Both linear connections are nonsymmetric and consequently admit torsion. A metric tensor is defined in terms of the building blocks of the structure. The condition for this metric to be a Finslerian one is obtained. Also, the condition for an FAP-space to be an AP-one is given.

A stereoscopic look into the bulk

DOE PAGES

Czech, Bartlomiej; Lamprou, Lampros; McCandlish, Samuel; ...

2016-07-26

Here, we present the foundation for a holographic dictionary with depth perception. The dictionary consists of natural CFT operators whose duals are simple, diffeomorphism-invariant bulk operators. The CFT operators of interest are the “OPE blocks,” contributions to the OPE from a single conformal family. In holographic theories, we show that the OPE blocks are dual at leading order in 1/N to integrals of effective bulk fields along geodesics or homogeneous minimal surfaces in anti-de Sitter space. One widely studied example of an OPE block is the modular Hamiltonian, which is dual to the fluctuation in the area of a minimalmore » surface. Thus, our operators pave the way for generalizing the Ryu-Takayanagi relation to other bulk fields. Although the OPE blocks are non-local operators in the CFT, they admit a simple geometric description as fields in kinematic space — the space of pairs of CFT points. We develop the tools for constructing local bulk operators in terms of these non-local objects. The OPE blocks also allow for conceptually clean and technically simple derivations of many results known in the literature, including linearized Einstein’s equations and the relation between conformal blocks and geodesic Witten diagrams.« less

Blockbusters: Ideas for the Block Center.

ERIC Educational Resources Information Center

Adams, Polly K.; Nesmith, Jaynie

1996-01-01

Goals of block building in early childhood classrooms focus on physical, social, cognitive, and emotional development. Reports survey results of the value teachers place on block play. Offers illustrations of task cards to use with blocks in math, language arts, social studies, and science. Discusses guidelines and suggests idea cards and sentence…

DNA-programmable nanoparticle crystallization.

PubMed

Park, Sung Yong; Lytton-Jean, Abigail K R; Lee, Byeongdu; Weigand, Steven; Schatz, George C; Mirkin, Chad A

2008-01-31

It was first shown more than ten years ago that DNA oligonucleotides can be attached to gold nanoparticles rationally to direct the formation of larger assemblies. Since then, oligonucleotide-functionalized nanoparticles have been developed into powerful diagnostic tools for nucleic acids and proteins, and into intracellular probes and gene regulators. In contrast, the conceptually simple yet powerful idea that functionalized nanoparticles might serve as basic building blocks that can be rationally assembled through programmable base-pairing interactions into highly ordered macroscopic materials remains poorly developed. So far, the approach has mainly resulted in polymerization, with modest control over the placement of, the periodicity in, and the distance between particles within the assembled material. That is, most of the materials obtained thus far are best classified as amorphous polymers, although a few examples of colloidal crystal formation exist. Here, we demonstrate that DNA can be used to control the crystallization of nanoparticle-oligonucleotide conjugates to the extent that different DNA sequences guide the assembly of the same type of inorganic nanoparticle into different crystalline states. We show that the choice of DNA sequences attached to the nanoparticle building blocks, the DNA linking molecules and the absence or presence of a non-bonding single-base flexor can be adjusted so that gold nanoparticles assemble into micrometre-sized face-centred-cubic or body-centred-cubic crystal structures. Our findings thus clearly demonstrate that synthetically programmable colloidal crystallization is possible, and that a single-component system can be directed to form different structures.

Molecular Building Block-Based Electronic Charges for High-Throughput Screening of Metal-Organic Frameworks for Adsorption Applications.

PubMed

Argueta, Edwin; Shaji, Jeena; Gopalan, Arun; Liao, Peilin; Snurr, Randall Q; Gómez-Gualdrón, Diego A

2018-01-09

Metal-organic frameworks (MOFs) are porous crystalline materials with attractive properties for gas separation and storage. Their remarkable tunability makes it possible to create millions of MOF variations but creates the need for fast material screening to identify promising structures. Computational high-throughput screening (HTS) is a possible solution, but its usefulness is tied to accurate predictions of MOF adsorption properties. Accurate adsorption simulations often require an accurate description of electrostatic interactions, which depend on the electronic charges of the MOF atoms. HTS-compatible methods to assign charges to MOF atoms need to accurately reproduce electrostatic potentials (ESPs) and be computationally affordable, but current methods present an unsatisfactory trade-off between computational cost and accuracy. We illustrate a method to assign charges to MOF atoms based on ab initio calculations on MOF molecular building blocks. A library of building blocks with built-in charges is thus created and used by an automated MOF construction code to create hundreds of MOFs with charges "inherited" from the constituent building blocks. The molecular building block-based (MBBB) charges are similar to REPEAT charges-which are charges that reproduce ESPs obtained from ab initio calculations on crystallographic unit cells of nanoporous crystals-and thus similar predictions of adsorption loadings, heats of adsorption, and Henry's constants are obtained with either method. The presented results indicate that the MBBB method to assign charges to MOF atoms is suitable for use in computational high-throughput screening of MOFs for applications that involve adsorption of molecules such as carbon dioxide.

Statistical analysis of atmospheric turbulence about a simulated block building

NASA Technical Reports Server (NTRS)

Steely, S. L., Jr.

1981-01-01

An array of towers instrumented to measure the three components of wind speed was used to study atmospheric flow about a simulated block building. Two-point spacetime correlations of the longitudinal velocity component were computed along with two-point spatial correlations. These correlations are in good agreement with fundamental concepts of fluid mechanics. The two-point spatial correlations computed directly were compared with correlations predicted by Taylor's hypothesis and excellent agreement was obtained at the higher levels which were out of the building influence. The correlations fall off significantly in the building wake but recover beyond the wake to essentially the same values in the undisturbed, higher regions.

"Looking through the Eyes of the Learner": Implementation of Building Blocks for Student Engagement

ERIC Educational Resources Information Center

D'Annolfo, Suzanne Cordier; Schumann, Jeffrey A.

2012-01-01

The Building Blocks for Student Engagement (BBSE) protocol was designed to provide a consistent framework of common language and a visual point of reference shared among students, teachers and school leaders to keep a laser-like focus on the instructional core and student engagement. Grounded in brain-based learning and implemented in urban,…

Oligomers and Polymers Based on Pentacene Building Blocks

PubMed Central

Lehnherr, Dan; Tykwinski, Rik R.

2010-01-01

Functionalized pentacene derivatives continue to provide unique materials for organic semiconductor applications. Although oligomers and polymers based on pentacene building blocks remain quite rare, recent synthetic achievements have provided a number of examples with varied structural motifs. This review highlights recent work in this area and, when possible, contrasts the properties of defined-length pentacene oligomers to those of mono- and polymeric systems.

Public Opinion on Youth, Crime and Race: A Guide for Advocates. Building Blocks for Youth.

ERIC Educational Resources Information Center

Soler, Mark

This guide summarizes public opinion research on youth and juvenile justice issues from the Building Blocks for Youth focus groups and various national polls. Overall, the public is less fearful about crime than in the past but believes juvenile crime is increasing. There is serious public concern about the effectiveness of the juvenile justice…

A “fullerene-carbon nanotube” structure with tunable mechanical properties

NASA Astrophysics Data System (ADS)

Ji, W. M.; Zhang, L. W.; Liew, K. M.

2018-03-01

Carbon-based nanostructures have drawn tremendous research interest and become promising building blocks for the new generation of smart sensors and devices. Utilizing a bottom-up strategy, the chemical interconnecting sp 3 covalent bond between carbon building blocks is an efficient way to enhance its Young's modulus and ductility. The formation of sp 3 covalent bond, however, inevitably degrades its ultimate tensile strength caused by stress concentration at the junction. By performing a molecular dynamics simulation of tensile deformation for a fullerene-carbon nanotube (FCNT) structure, we propose a tunable strategy in which fullerenes with various angle energy absorption capacities are utilized as building blocks to tune their ductile behavior, while still maintaining a good ultimate tensile strength of the carbon building blocks. A higher ultimate tensile strength is revealed with the reduction of stress concentration at the junction. A brittle-to-ductile transition during the tensile deformation is detected through the structural modification. The development of ductile behavior is attributed to the improvement of energy propagation ability during the fracture initiation, in which the released energy from bonds fracture is mitigated properly, leading to the further development of mechanical properties.

De novo design of molecular architectures by evolutionary assembly of drug-derived building blocks.

PubMed

Schneider, G; Lee, M L; Stahl, M; Schneider, P

2000-07-01

An evolutionary algorithm was developed for fragment-based de novo design of molecules (TOPAS, TOPology-Assigning System). This stochastic method aims at generating a novel molecular structure mimicking a template structure. A set of approximately 25,000 fragment structures serves as the building block supply, which were obtained by a straightforward fragmentation procedure applied to 36,000 known drugs. Eleven reaction schemes were implemented for both fragmentation and building block assembly. This combination of drug-derived building blocks and a restricted set of reaction schemes proved to be a key for the automatic development of novel, synthetically tractable structures. In a cyclic optimization process, molecular architectures were generated from a parent structure by virtual synthesis, and the best structure of a generation was selected as the parent for the subsequent TOPAS cycle. Similarity measures were used to define 'fitness', based on 2D-structural similarity or topological pharmacophore distance between the template molecule and the variants. The concept of varying library 'diversity' during a design process was consequently implemented by using adaptive variant distributions. The efficiency of the design algorithm was demonstrated for the de novo construction of potential thrombin inhibitors mimicking peptide and non-peptide template structures.

Versatile plasmid-based expression systems for Gram-negative bacteria--General essentials exemplified with the bacterium Ralstonia eutropha H16.

PubMed

Gruber, Steffen; Schwab, Helmut; Koefinger, Petra

2015-12-25

The Gram-negative bacterium Escherichia coli is currently the most efficient and widely used prokaryotic host for recombinant protein and metabolite production. However, due to some limitations and to various interesting features of other Gram-negative bacteria efficient vector systems applicable to a broad range are desired. Basic building blocks for plasmid-based vectors include besides the need for a suitable selection marker in the first line a proper replication and maintenance system. In addition to these basic requirements, further elements are needed for Gram-negative bacteria beyond E. coli, such as Pseudomonas pudita, Ralstonia eutropha, Burkholderia glumae or Acinetobacter sp.. Established building blocks have to be adapted and new building blocks providing the desired functions need to be identified and exploited. This minireview addresses so far described and used genetic elements for broad host range replication, efficient plasmid maintenance, and conjugative plasmid transfer as well as expression elements and protein secretion signals. The industrially important bacterium R. eutropha H16 was chosen as a model organism to provide specific data on the effectivity and utility of building blocks based on such genetic elements. Copyright © 2015 Elsevier B.V. All rights reserved.

Geospatial-enabled Data Exploration and Computation through Data Infrastructure Building Blocks

NASA Astrophysics Data System (ADS)

Song, C. X.; Biehl, L. L.; Merwade, V.; Villoria, N.

2015-12-01

Geospatial data are present everywhere today with the proliferation of location-aware computing devices and sensors. This is especially true in the scientific community where large amounts of data are driving research and education activities in many domains. Collaboration over geospatial data, for example, in modeling, data analysis and visualization, must still overcome the barriers of specialized software and expertise among other challenges. The GABBs project aims at enabling broader access to geospatial data exploration and computation by developing spatial data infrastructure building blocks that leverage capabilities of end-to-end application service and virtualized computing framework in HUBzero. Funded by NSF Data Infrastructure Building Blocks (DIBBS) initiative, GABBs provides a geospatial data architecture that integrates spatial data management, mapping and visualization and will make it available as open source. The outcome of the project will enable users to rapidly create tools and share geospatial data and tools on the web for interactive exploration of data without requiring significant software development skills, GIS expertise or IT administrative privileges. This presentation will describe the development of geospatial data infrastructure building blocks and the scientific use cases that help drive the software development, as well as seek feedback from the user communities.

13. A southeastward view of buildings #3 (on the right), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

13. A southeastward view of buildings #3 (on the right), building #5 ( to the immediate left of building #3), and buildings #6-B (low building on the far left) and #6 ( to the immediate rear of #6-B). - American Chain & Cable Company, East Princess Street (400 Block), York, York County, PA

An easy-to-build remote laboratory with data transfer using the Internet School Experimental System

NASA Astrophysics Data System (ADS)

Schauer, František; Lustig, František; Dvořák, Jiří; Ožvoldová, Miroslava

2008-07-01

The present state of information communication technology makes it possible to devise and run computer-based e-laboratories accessible to any user with a connection to the Internet, equipped with very simple technical means and making full use of web services. Thus, the way is open for a new strategy of physics education with strongly global features, based on experiment and experimentation. We name this strategy integrated e-learning, and remote experiments across the Internet are the foundation for this strategy. We present both pedagogical and technical reasoning for the remote experiments and outline a simple system based on a server-client approach, and on web services and Java applets. We give here an outline of the prospective remote laboratory system with data transfer using the Internet School Experimental System (ISES) as hardware and ISES WEB Control kit as software. This approach enables the simple construction of remote experiments without building any hardware and virtually no programming, using a paste and copy approach with typical prebuilt blocks such as a camera view, controls, graphs, displays, etc. We have set up and operate at present seven experiments, running round the clock, with more than 12 000 connections since 2005. The experiments are widely used in practical teaching of both university and secondary level physics. The recording of the detailed steps the experimentor takes during the measurement enables detailed study of the psychological aspects of running the experiments. The system is ready for a network of universities to start covering the basic set of physics experiments. In conclusion we summarize the results achieved and experiences of using remote experiments built on the ISES hardware system.

1. Historic American Buildings Survey E. W. Russell, Photographer, October ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Historic American Buildings Survey E. W. Russell, Photographer, October 17, 1935 51-69 Government St. BLOCK OF BUILDINGS ON GOVERNMENT ST. (S. SIDE) BETWEEN WATER AND ROYAL STREETS - 51-69 Government Street (Commercial Building), Mobile, Mobile County, AL

Computational Design of Self-Assembling Protein Nanomaterials with Atomic Level Accuracy

DOE Office of Scientific and Technical Information (OSTI.GOV)

King, Neil P.; Sheffler, William; Sawaya, Michael R.

2015-09-17

We describe a general computational method for designing proteins that self-assemble to a desired symmetric architecture. Protein building blocks are docked together symmetrically to identify complementary packing arrangements, and low-energy protein-protein interfaces are then designed between the building blocks in order to drive self-assembly. We used trimeric protein building blocks to design a 24-subunit, 13-nm diameter complex with octahedral symmetry and a 12-subunit, 11-nm diameter complex with tetrahedral symmetry. The designed proteins assembled to the desired oligomeric states in solution, and the crystal structures of the complexes revealed that the resulting materials closely match the design models. The method canmore » be used to design a wide variety of self-assembling protein nanomaterials.« less

Expressivism, Relativism, and the Analytic Equivalence Test

PubMed Central

Frápolli, Maria J.; Villanueva, Neftalí

2015-01-01

The purpose of this paper is to show that, pace (Field, 2009), MacFarlane’s assessment relativism and expressivism should be sharply distinguished. We do so by arguing that relativism and expressivism exemplify two very different approaches to context-dependence. Relativism, on the one hand, shares with other contemporary approaches a bottom–up, building block, model, while expressivism is part of a different tradition, one that might include Lewis’ epistemic contextualism and Frege’s content individuation, with which it shares an organic model to deal with context-dependence. The building-block model and the organic model, and thus relativism and expressivism, are set apart with the aid of a particular test: only the building-block model is compatible with the idea that there might be analytically equivalent, and yet different, propositions. PMID:26635690

Fast and Facile Synthesis of 4-Nitrophenyl 2-Azidoethylcarbamate Derivatives from N-Fmoc-Protected α-Amino Acids as Activated Building Blocks for Urea Moiety-Containing Compound Library.

PubMed

Chen, Ying-Ying; Chang, Li-Te; Chen, Hung-Wei; Yang, Chia-Ying; Hsin, Ling-Wei

2017-03-13

A fast and facile synthesis of a series of 4-nitrophenyl 2-azidoethylcarbamate derivatives as activated urea building blocks was developed. The N-Fmoc-protected 2-aminoethyl mesylates derived from various commercially available N-Fmoc-protected α-amino acids, including those having functionalized side chains with acid-labile protective groups, were directly transformed into 4-nitrophenyl 2-azidoethylcarbamate derivatives in 1 h via a one-pot two-step reaction. These urea building blocks were utilized for the preparation of a series of urea moiety-containing mitoxantrone-amino acid conjugates in 75-92% yields and parallel solution-phase synthesis of a urea compound library consisted of 30 members in 38-70% total yields.

Mission building blocks for outer solar system exploration.

NASA Technical Reports Server (NTRS)

Herman, D.; Tarver, P.; Moore, J.

1973-01-01

Description of the technological building blocks required for exploring the outer planets with maximum scientific yields under stringent resource constraints. Two generic spacecraft types are considered: the Mariner and the Pioneer. Following a discussion of the outer planet mission constraints, the evolutionary development of spacecraft, probes, and propulsion building blocks is presented. Then, program genealogies are shown for Pioneer and Mariner missions and advanced propulsion systems to illustrate the soundness of a program based on spacecraft modification rather than on the development of new spacecraft for each mission. It is argued that, for minimum costs, technological advancement should occur in an evolutionary manner from mission to mission. While this strategy is likely to result in compromises on specific missions, the realization of the overall objectives calls for an advance commitment to the entire mission series.

2. EXTERIOR VIEW OF BUILDING 25B (TEST CHAMBER BUILDING) AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. EXTERIOR VIEW OF BUILDING 25B (TEST CHAMBER BUILDING) AND WIND TUNNEL, LOOKING NORTHWEST (1991). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

A model to predict radon exhalation from walls to indoor air based on the exhalation from building material samples.

PubMed

Sahoo, B K; Sapra, B K; Gaware, J J; Kanse, S D; Mayya, Y S

2011-06-01

In recognition of the fact that building materials are an important source of indoor radon, second only to soil, surface radon exhalation fluxes have been extensively measured from the samples of these materials. Based on this flux data, several researchers have attempted to predict the inhalation dose attributable to radon emitted from walls and ceilings made up of these materials. However, an important aspect not considered in this methodology is the enhancement of the radon flux from the wall or the ceiling constructed using the same building material. This enhancement occurs mainly because of the change in the radon diffusion process from the former to the latter configuration. To predict the true radon flux from the wall based on the flux data of building material samples, we now propose a semi-empirical model involving radon diffusion length and the physical dimensions of the samples as well as wall thickness as other input parameters. This model has been established by statistically fitting the ratio of the solution to radon diffusion equations for the cases of three-dimensional cuboidal shaped building materials (such as brick, concrete block) and one dimensional wall system to a simple mathematical function. The model predictions have been validated against the measurements made at a new construction site. This model provides an alternative tool (substitute to conventional 1-D model) to estimate radon flux from a wall without relying on ²²⁶Ra content, radon emanation factor and bulk density of the samples. Moreover, it may be very useful in the context of developing building codes for radon regulation in new buildings. Copyright © 2011 Elsevier B.V. All rights reserved.

Block Play: Practical Suggestions for Common Dilemmas

ERIC Educational Resources Information Center

Tunks, Karyn Wellhousen

2009-01-01

Learning materials and teaching methods used in early childhood classrooms have fluctuated greatly over the past century. However, one learning tool has stood the test of time: Wood building blocks, often called unit blocks, continue to be a source of pleasure and learning for young children at play. Wood blocks have the unique capacity to engage…

Molecular docking sites designed for the generation of highly crystalline covalent organic frameworks

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ascherl, Laura; Sick, Torben; Margraf, Johannes

Covalent organic frameworks (COFs) formed by connecting multidentate organic building blocks through covalent bonds provide a platform for designing multifunctional porous materials with atomic precision. As they are promising materials for applications in optoelectronics, they would benefit from a maximum degree of long-range order within the framework, which has remained a major challenge. We have developed a synthetic concept to allow consecutive COF sheets to lock in position during crystal growth, and thus minimize the occurrence of stacking faults and dislocations. Hereby, the three-dimensional conformation of propeller-shaped molecular building units was used to generate well-defined periodic docking sites, which guidedmore » the attachment of successive building blocks that, in turn, promoted long-range order during COF formation. This approach enables us to achieve a very high crystallinity for a series of COFs that comprise tri- and tetradentate central building blocks. We expect this strategy to be transferable to a broad range of customized COFs.« less

Emergent mechanics of biological structures

PubMed Central

Dumont, Sophie; Prakash, Manu

2014-01-01

Mechanical force organizes life at all scales, from molecules to cells and tissues. Although we have made remarkable progress unraveling the mechanics of life's individual building blocks, our understanding of how they give rise to the mechanics of larger-scale biological structures is still poor. Unlike the engineered macroscopic structures that we commonly build, biological structures are dynamic and self-organize: they sculpt themselves and change their own architecture, and they have structural building blocks that generate force and constantly come on and off. A description of such structures defies current traditional mechanical frameworks. It requires approaches that account for active force-generating parts and for the formation of spatial and temporal patterns utilizing a diverse array of building blocks. In this Perspective, we term this framework “emergent mechanics.” Through examples at molecular, cellular, and tissue scales, we highlight challenges and opportunities in quantitatively understanding the emergent mechanics of biological structures and the need for new conceptual frameworks and experimental tools on the way ahead. PMID:25368421

Molecular docking sites designed for the generation of highly crystalline covalent organic frameworks

NASA Astrophysics Data System (ADS)

Ascherl, Laura; Sick, Torben; Margraf, Johannes T.; Lapidus, Saul H.; Calik, Mona; Hettstedt, Christina; Karaghiosoff, Konstantin; Döblinger, Markus; Clark, Timothy; Chapman, Karena W.; Auras, Florian; Bein, Thomas

2016-04-01

Covalent organic frameworks (COFs) formed by connecting multidentate organic building blocks through covalent bonds provide a platform for designing multifunctional porous materials with atomic precision. As they are promising materials for applications in optoelectronics, they would benefit from a maximum degree of long-range order within the framework, which has remained a major challenge. We have developed a synthetic concept to allow consecutive COF sheets to lock in position during crystal growth, and thus minimize the occurrence of stacking faults and dislocations. Hereby, the three-dimensional conformation of propeller-shaped molecular building units was used to generate well-defined periodic docking sites, which guided the attachment of successive building blocks that, in turn, promoted long-range order during COF formation. This approach enables us to achieve a very high crystallinity for a series of COFs that comprise tri- and tetradentate central building blocks. We expect this strategy to be transferable to a broad range of customized COFs.

Elfin: An algorithm for the computational design of custom three-dimensional structures from modular repeat protein building blocks.

PubMed

Yeh, Chun-Ting; Brunette, T J; Baker, David; McIntosh-Smith, Simon; Parmeggiani, Fabio

2018-02-01

Computational protein design methods have enabled the design of novel protein structures, but they are often still limited to small proteins and symmetric systems. To expand the size of designable proteins while controlling the overall structure, we developed Elfin, a genetic algorithm for the design of novel proteins with custom shapes using structural building blocks derived from experimentally verified repeat proteins. By combining building blocks with compatible interfaces, it is possible to rapidly build non-symmetric large structures (>1000 amino acids) that match three-dimensional geometric descriptions provided by the user. A run time of about 20min on a laptop computer for a 3000 amino acid structure makes Elfin accessible to users with limited computational resources. Protein structures with controlled geometry will allow the systematic study of the effect of spatial arrangement of enzymes and signaling molecules, and provide new scaffolds for functional nanomaterials. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of site frequencies from building records

USGS Publications Warehouse

Celebi, M.

2003-01-01

A simple procedure to identify site frequencies using earthquake response records from roofs and basements of buildings is presented. For this purpose, data from five different buildings are analyzed using only spectral analyses techniques. Additional data such as free-field records in close proximity to the buildings and site characterization data are also used to estimate site frequencies and thereby to provide convincing evidence and confirmation of the site frequencies inferred from the building records. Furthermore, simple code-formula is used to calculate site frequencies and compare them with the identified site frequencies from records. Results show that the simple procedure is effective in identification of site frequencies and provides relatively reliable estimates of site frequencies when compared with other methods. Therefore the simple procedure for estimating site frequencies using earthquake records can be useful in adding to the database of site frequencies. Such databases can be used to better estimate site frequencies of those sites with similar geological structures.

The Influence of Building Block Play on Mathematics Achievement and Logical and Divergent Thinking in Italian Primary School Mathematics Classes

ERIC Educational Resources Information Center

Pirrone, Concetta; Tienken, Christopher H.; Pagano, Tatiana; Di Nuovo, Santo

2018-01-01

In an experimental study to explain the effect of structured Building Block Play with LEGO™ bricks on 6-year-old student mathematics achievement and in the areas of logical thinking, divergent thinking, nonverbal reasoning, and mental imagery, students in the experimental group scored significantly higher (p = 0.05) in mathematics achievement and…

Novel single photon sources for new generation of quantum communications

DTIC Science & Technology

2017-06-13

be used as building blocks for quantum cryptography and quantum key distribution There were numerous important achievements for the projects in the...single photon sources that will be used as build- ing blocks for quantum cryptography and quantum key distribution There were numerous im- portant...and enable absolutely secured information transfer between distant nodes – key prerequisite for quantum cryptography . Experiment: the experimental

Building Blocks for Transport-Class Hybrid and Turboelectric Vehicles

NASA Technical Reports Server (NTRS)

Jankovsky, Amy; Bowman, Cheryl; Jansen, Ralph

2016-01-01

NASA has been investing in research efforts to define potential vehicles that use hybrid and turboelectric propulsion to enable savings in fuel burn and carbon usage. This paper overviews the fundamental building blocks that have been derived from those studies and details what key performance parameters have been defined, what key ground and flight tests need to occur, and highlights progress toward each.

2016 Summer Series - Kenneth Cheung: Building Blocks for Aerospace Structures

NASA Image and Video Library

2016-06-16

Strong, ultra-lightweight materials are expected to play a key role in the design of future aircraft and space vehicles. Lower structural mass leads to improved performance, maneuverability, efficiency, range and payload capacity. Dr. Kenneth Cheung is developing cellular composite building blocks, or digital materials, to create transformable aerostructures. In his presentation, Dr. Cheung will discuss the implications of the digital materials and morphing structures.

Supramolecular Lego assembly towards three-dimensional multi-responsive hydrogels.

PubMed

Ma, Chunxin; Li, Tiefeng; Zhao, Qian; Yang, Xuxu; Wu, Jingjun; Luo, Yingwu; Xie, Tao

2014-08-27

Inspired by the assembly of Lego toys, hydrogel building blocks with heterogeneous responsiveness are assembled utilizing macroscopic supramolecular recognition as the adhesion force. The Lego hydrogel provides 3D transformation upon pH variation. After disassembly of the building blocks by changing the oxidation state, they can be re-assembled into a completely new shape. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Damage of modern building materials by microscopic fungi].

PubMed

Chuenko, A I; Karpenko, Iu V

2011-01-01

Resistance of three materials, produced on the basis of concrete compounds to the action of microscopic fungi, isolated from damaged living buildings, has been first investigated. It has been shown that samples of froth-block and thermoeffective block had low fungal resistance, in contrast to samples of cellular polystyrene concrete, which were resistant to fungal action, that can be associated with peculiarities of their component composition.

Building Blocks for Father Involvement: Building Block 1--Appreciating How Fathers Give Children a Head Start

ERIC Educational Resources Information Center

US Department of Health and Human Services, Head Start Bureau, 2004

2004-01-01

Nearly 30 years ago, leading child psychologist Michael E. Lamb reminded us that fathers are the "forgotten contributors to child development." Since then, much work has been done to explore the ways fathers uniquely contribute to the healthy development of their children. Scholars now know that boys and girls who grow up with an involved father,…

Highly crystalline covalent organic frameworks from flexible building blocks.

PubMed

Xu, Liqian; Ding, San-Yuan; Liu, Junmin; Sun, Junliang; Wang, Wei; Zheng, Qi-Yu

2016-03-28

Two novel 2D covalent organic frameworks (TPT-COF-1 and TPT-COF-2) were synthesized from the flexible 2,4,6-triaryloxy-1,3,5-triazine building blocks on a gram scale, which show high crystallinity and large surface area. The controllable formation of highly ordered frameworks is mainly attributed to the self-assembly Piedfort unit of 2,4,6-triaryloxy-1,3,5-triazine.

Functional Perfluoroalkyl Polyhedral Oligomeric Silsesquioxane (F-POSS): Building Blocks for Low Surface Energy Materials

DTIC Science & Technology

2010-10-21

Technical Paper 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Functional Perfluoroalkyl Polyhedral Oligomeric Silsesquioxane (F...long chain fluorinated alkyl groups ranging from 6-12 carbon atoms in length. Herein, a disilanol perfluoroalkyl polyhedral oligomeric...FUNCTIONAL PERFLUOROALKYL POLYHEDRAL OLIGOMERIC SILSESQUIOXANES (F-POSS): BUILDING BLOCKS FOR LOW SURFACE ENERGY MATERIA LS Sean M Rami,.e:, Yvonne Dia

Expansion and improvements of the FORMA system for response and load analysis. Volume 1: Programming manual

NASA Technical Reports Server (NTRS)

Wohlen, R. L.

1976-01-01

Techniques are presented for the solution of structural dynamic systems on an electronic digital computer using FORMA (FORTRAN Matrix Analysis). FORMA is a library of subroutines coded in FORTRAN 4 for the efficient solution of structural dynamics problems. These subroutines are in the form of building blocks that can be put together to solve a large variety of structural dynamics problems. The obvious advantage of the building block approach is that programming and checkout time are limited to that required for putting the blocks together in the proper order.

Dual-mode MOS SOI nanoscale transistor serving as a building block for optical communication between blocks

NASA Astrophysics Data System (ADS)

Bendayan, Michael; Sabo, Roi; Zolberg, Roee; Mandelbaum, Yaakov; Chelly, Avraham; Karsenty, Avi

2017-02-01

We developed a new type of silicon MOSFET Quantum Well transistor, coupling both electronic and optical properties which should overcome the indirect silicon bandgap constraint, and serve as a future light emitting device in the range 0.8-2μm, as part of a new building block in integrated circuits allowing ultra-high speed processors. Such Quantum Well structure enables discrete energy levels for light recombination. Model and simulations of both optical and electric properties are presented pointing out the influence of the channel thickness and the drain voltage on the optical emission spectrum.

Single block three-dimensional volume grids about complex aerodynamic vehicles

NASA Technical Reports Server (NTRS)

Alter, Stephen J.; Weilmuenster, K. James

1993-01-01

This paper presents an alternate approach for the generation of volumetric grids for supersonic and hypersonic flows about complex configurations. The method uses parametric two dimensional block face grid definition within the framework of GRIDGEN2D. The incorporation of face decomposition reduces complex surfaces to simple shapes. These simple shapes are combined to obtain the final face definition. The advantages of this method include the reduction of overall grid generation time through the use of vectorized computer code, the elimination of the need to generate matching block faces, and the implementation of simplified boundary conditions. A simple axisymmetric grid is used to illustrate this method. In addition, volume grids for two complex configurations, the Langley Lifting Body (HL-20) and the Space Shuttle Orbiter, are shown.

Selfish altruism, fierce cooperation and the predator.

PubMed

Askitas, Nikolaos

2018-12-01

This paper suggests a new way to think about a famous question: what explains cooperation in nature and in particular in humans? I argue that, for an evolutionary biologist as well as a quantitative social scientist, the triangle of two 'teammates' in the presence of a predator (passing and shooting in two-on-one situations) is one of the fundamental conceptual building-blocks for understanding these phenomena because in such a situation the fact that life is packaged in many distinct enclosures (and not in one big monolithic blob) can unfold its comparative advantage. I show how, in the presence of a predator, cooperative equilibria emerge among entirely selfish teammates if we infinitesimally bias the lead player in the selfish direction or assign a computational burden on the predator due to the presence of a teammate. I argue that 'predators' are common in the biological jungle but also in everyday human settings. Intuitively, this paper builds on the simple idea - a familiar one to a biologist observing the natural world but perhaps less so to social scientists - that everybody has enemies.

Conformal Nanocoatings with Uniform and Controllable Thickness on Microstructured Surfaces: A General Assembly Route.

PubMed

Hou, Yi; Wang, Zhen; Cai, Chao; Hao, Xi; Li, Dongdong; Zhao, Ning; Zhao, Yiping; Chen, Li; Ma, Hongwei; Xu, Jian

2018-02-01

Assembling nanoparticles (NPs) on various surfaces are intensively investigated for the construction of functional nanocoatings; however, it is still a challenge to fabricate conformal nanocoatings uniformly on surfaces having micro- or nanostructures. Herein, it is demonstrated that the negatively charged SiO 2 NPs and the positively charged silicon coupling agent can be assembled layer-by-layer on the microstructures based on the combination of electrostatic interaction and condensation reaction. Conformal nanocoatings with controllable thickness are formed on the microstructured surfaces with different compositions and morphologies. The formation mechanism is confirmed by using quartz crystal microbalance with dissipation (QCM-D) to study the assembly process in real time. The universality of this method is illustrated by using other reactive building blocks with opposite charge to build up the conformal nanocoatings. Application in the preparation of antireflective nanocoatings on nonplanar optical materials is demonstrated. This simple, versatile, and scalable strategy for the preparation of conformal nanocoatings is promising for practical applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

General synthesis of inorganic single-walled nanotubes

PubMed Central

Ni, Bing; Liu, Huiling; Wang, Peng-peng; He, Jie; Wang, Xun

2015-01-01

The single-walled nanotube (SWNT) is an interesting nanostructure for fundamental research and potential applications. However, very few inorganic SWNTs are available to date due to the lack of efficient fabrication methods. Here we synthesize four types of SWNT: sulfide; hydroxide; phosphate; and polyoxometalate. Each type of SWNT possesses essentially uniform diameters. Detailed studies illustrate that the formation of SWNTs is initiated by the self-coiling of the corresponding ultrathin nanostructure embryo/building blocks on the base of weak interactions between them, which is not limited to specific compounds or crystal structures. The interactions between building blocks can be modulated by varying the solvents used, thus multi-walled tubes can also be obtained. Our results reveal that the generalized synthesis of inorganic SWNTs can be achieved by the self-coiling of ultrathin building blocks under the proper weak interactions. PMID:26510862

Simplified and quick electrical modeling for dye sensitized solar cells: An experimental and theoretical investigation

NASA Astrophysics Data System (ADS)

de Andrade, Rocelito Lopes; de Oliveira, Matheus Costa; Kohlrausch, Emerson Cristofer; Santos, Marcos José Leite

2018-05-01

This work presents a new and simple method for determining IPH (current source dependent on luminance), I0 (reverse saturation current), n (ideality factor), RP and RS, (parallel and series resistance) to build an electrical model for dye sensitized solar cells (DSSCs). The electrical circuit parameters used in the simulation and to generate theoretical curves for the single diode electrical model were extracted from I-V curves of assembled DSSCs. Model validation was performed by assembling five different types of DSSCs and evaluating the following parameters: effect of a TiO2 blocking/adhesive layer, thickness of the TiO2 layer and the presence of a light scattering layer. In addition, irradiance, temperature, series and parallel resistance, ideality factor and reverse saturation current were simulated.

An RNA Origami Octahedron with Intrinsic siRNAs for Potent Gene Knockdown.

PubMed

Høiberg, Hans Christian; Sparvath, Steffen M; Andersen, Veronica L; Kjems, Jørgen; Andersen, Ebbe S

2018-05-26

The fields of DNA and RNA nanotechnology have established nucleic acids as valuable building blocks for functional nanodevices with applications in nanomedicine. Here, a simple method for designing and assembling a 3D scaffolded RNA origami wireframe structure with intrinsic functioning small interfering RNAs (siRNAs) embedded is introduced. Uniquely, the method uses an mRNA fragment as scaffold strand, which is folded by sequence-complementarity of nine shorter synthetic strands. High-yield production of the intended 3D structure is verified by transmission electron microscopy (TEM). Production of functional siRNAs is facilitated by incorporating recognition sites for Dicer at selected locations in the structure, and efficient silencing of a target reporter gene is demonstrated. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functional organic materials based on polymerized liquid-crystal monomers: supramolecular hydrogen-bonded systems.

PubMed

Broer, Dirk J; Bastiaansen, Cees M W; Debije, Michael G; Schenning, Albertus P H J

2012-07-16

Functional organic materials are of great interest for a variety of applications. To obtain precise functional properties, well-defined hierarchically ordered supramolecular materials are crucial. The self-assembly of liquid crystals has proven to be an extremely useful tool in the development of well-defined nanostructured materials. We have chosen the illustrative example of photopolymerizable hydrogen-bonding mesogens to show that a wide variety of functional materials can be made from a relatively simple set of building blocks. Upon mixing these compounds with other reactive mesogens, nematic, chiral nematic, and smectic or columnar liquid-crystalline phases can be formed that can be applied as actuators, sensors and responsive reflectors, and nanoporous membranes, respectively. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Epoxy Monomers Cured by High Cellulosic Nanocrystal Loading.

PubMed

Khelifa, Farid; Habibi, Youssef; Bonnaud, Leila; Dubois, Philippe

2016-04-27

The present study focuses on the use of cellulose nanocrystals (CNC) as the main constituent of a nanocomposite material and takes advantage of hydroxyl groups, characteristic of the CNC chemical structure, to thermally cross-link an epoxy resin. An original and simple approach is proposed, based on the collective sticking of CNC building blocks with the help of a DGEBA/TGPAP-based epoxy resin. Scientific findings suggest that hydroxyl groups act as a toxic-free cross-linking agent of the resin. The enhanced protection against water degradation as compared to neat CNC film and the improvement of mechanical properties of the synthesized films are attributed to a good compatibility between the CNC and the resin. Moreover, the preservation of CNC optical properties at high concentrations opens the way to applying these materials in photonic devices.

Structure and function of polyketide biosynthetic enzymes: various strategies for production of structurally diverse polyketides.

PubMed

Miyanaga, Akimasa

2017-12-01

Polyketides constitute a large family of natural products that display various biological activities. Polyketides exhibit a high degree of structural diversity, although they are synthesized from simple acyl building blocks. Recent biochemical and structural studies provide a better understanding of the biosynthetic logic of polyketide diversity. This review highlights the biosynthetic mechanisms of structurally unique polyketides, β-amino acid-containing macrolactams, enterocin, and phenolic lipids. Functional and structural studies of macrolactam biosynthetic enzymes have revealed the unique biosynthetic machinery used for selective incorporation of a rare β-amino acid starter unit into the polyketide skeleton. Biochemical and structural studies of cyclization enzymes involved in the biosynthesis of enterocin and phenolic lipids provide mechanistic insights into how these enzymes diversify the carbon skeletons of their products.

ChemCalc: a building block for tomorrow's chemical infrastructure.

PubMed

Patiny, Luc; Borel, Alain

2013-05-24

Web services, as an aspect of cloud computing, are becoming an important part of the general IT infrastructure, and scientific computing is no exception to this trend. We propose a simple approach to develop chemical Web services, through which servers could expose the essential data manipulation functionality that students and researchers need for chemical calculations. These services return their results as JSON (JavaScript Object Notation) objects, which facilitates their use for Web applications. The ChemCalc project http://www.chemcalc.org demonstrates this approach: we present three Web services related with mass spectrometry, namely isotopic distribution simulation, peptide fragmentation simulation, and molecular formula determination. We also developed a complete Web application based on these three Web services, taking advantage of modern HTML5 and JavaScript libraries (ChemDoodle and jQuery).

Field-induced assembly of colloidal ellipsoids into well-defined microtubules

PubMed Central

Crassous, Jérôme J.; Mihut, Adriana M.; Wernersson, Erik; Pfleiderer, Patrick; Vermant, Jan; Linse, Per; Schurtenberger, Peter

2014-01-01

Current theoretical attempts to understand the reversible formation of stable microtubules and virus shells are generally based on shape-specific building blocks or monomers, where the local curvature of the resulting structure is explicitly built-in via the monomer geometry. Here we demonstrate that even simple ellipsoidal colloids can reversibly self-assemble into regular tubular structures when subjected to an alternating electric field. Supported by model calculations, we discuss the combined effects of anisotropic shape and field-induced dipolar interactions on the reversible formation of self-assembled structures. Our observations show that the formation of tubular structures through self-assembly requires much less geometrical and interaction specificity than previously thought, and advance our current understanding of the minimal requirements for self-assembly into regular virus-like structures. PMID:25409686

Strong circularly polarized luminescence from the supramolecular gels of an achiral gelator: tunable intensity and handedness.

PubMed

Shen, Zhaocun; Wang, Tianyu; Shi, Lin; Tang, Zhiyong; Liu, Minghua

2015-07-01

Although the importance of circularly polarized luminescence (CPL) materials has been widely recognized, the CPL responses of supramolecular gels are still rarely studied. Moreover, developing CPL materials based on supramolecular gels is of great significance, due to their special advantages and important applications. Herein, we report the first circularly polarized supramolecular gels self-assembled exclusively from a simple achiral C 3 -symmetric molecule. Most importantly, the excellent tunability of these novel CPL materials, which benefits from achiral molecular building blocks as well as the nature of supramolecular gels, has been investigated. Thus, the CPL intensity of these supramolecular gels is easily enhanced by mechanical stirring or doping chiral amines. The handedness of CPL signals is controlled by the chirality of organic amines.

Quantification of Soluble Sugars and Sugar Alcohols by LC-MS/MS.

PubMed

Feil, Regina; Lunn, John Edward

2018-01-01

Sugars are simple carbohydrates composed primarily of carbon, hydrogen, and oxygen. They play a central role in metabolism as sources of energy and as building blocks for synthesis of structural and nonstructural polymers. Many different techniques have been used to measure sugars, including refractometry, colorimetric and enzymatic assays, gas chromatography, high-performance liquid chromatography, and nuclear magnetic resonance spectroscopy. In this chapter we describe a method that combines an initial separation of sugars by high-performance anion-exchange chromatography (HPAEC) with detection and quantification by tandem mass spectrometry (MS/MS). This combination of techniques provides exquisite specificity, allowing measurement of a diverse range of high- and low-abundance sugars in biological samples. This method can also be used for isotopomer analysis in stable-isotope labeling experiments to measure metabolic fluxes.

Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis.

PubMed

Kärkäs, Markus D; Porco, John A; Stephenson, Corey R J

2016-09-14

The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the involvement of electronically excited states, generated upon absorption of photons. This produces transient reactive intermediates and significantly alters the reactivity of a chemical compound. The input of energy provided by light thus offers a means to produce strained and unique target compounds that cannot be assembled using thermal protocols. This review aims at highlighting photochemical transformations as a tool for rapidly accessing structurally and stereochemically diverse scaffolds. Synthetic designs based on photochemical transformations have the potential to afford complex polycyclic carbon skeletons with impressive efficiency, which are of high value in total synthesis.

Toward a low-cost, low-power, low-complexity DAC-based multilevel (M-ary QAM) coherent transmitter using compact linear optical field modulator

NASA Astrophysics Data System (ADS)

Dingel, Benjamin

2017-01-01

In this invited paper, we summarize the current developments in linear optical field modulators (LOFMs) for coherent multilevel optical transmitters. Our focus is the presentation of a new, novel LOFM design that provides beneficial and necessary features such as lowest hardware component counts, lowered insertion loss, smaller RF power consumption, smaller footprint, simple structure, and lowered cost. We refer to this modulator as called Double-Pass LOFM (DP-LOFM) that becomes the building block for high-performance, linear Dual-Polarization, In-Phase- Quadrature-Phase (DP-IQ) modulator. We analyze its performance in term of slope linearity, and present one of its unique feature -- a built-in compensation functionality that no other linear modulators possessed till now.

Large-area, lightweight and thick biomimetic composites with superior material properties via fast, economic, and green pathways.

PubMed

Walther, Andreas; Bjurhager, Ingela; Malho, Jani-Markus; Pere, Jaakko; Ruokolainen, Janne; Berglund, Lars A; Ikkala, Olli

2010-08-11

Although remarkable success has been achieved to mimic the mechanically excellent structure of nacre in laboratory-scale models, it remains difficult to foresee mainstream applications due to time-consuming sequential depositions or energy-intensive processes. Here, we introduce a surprisingly simple and rapid methodology for large-area, lightweight, and thick nacre-mimetic films and laminates with superior material properties. Nanoclay sheets with soft polymer coatings are used as ideal building blocks with intrinsic hard/soft character. They are forced to rapidly self-assemble into aligned nacre-mimetic films via paper-making, doctor-blading or simple painting, giving rise to strong and thick films with tensile modulus of 45 GPa and strength of 250 MPa, that is, partly exceeding nacre. The concepts are environmentally friendly, energy-efficient, and economic and are ready for scale-up via continuous roll-to-roll processes. Excellent gas barrier properties, optical translucency, and extraordinary shape-persistent fire-resistance are demonstrated. We foresee advanced large-scale biomimetic materials, relevant for lightweight sustainable construction and energy-efficient transportation.

A New Paradigm for Robotic Rovers

NASA Astrophysics Data System (ADS)

Clark, P. E.; Curtis, S. A.; Rilee, M. L.

We are in the process of developing rovers with extreme mobility needed to explore remote, rugged terrain. We call these systems Tetrahedral Explorer Technologies (TETs). Architecture is based on conformable tetrahedra, the simplest space-filling form, as building blocks, single or networked, where apices act as nodes from which struts reversibly deploy. The tetrahedral framework acts as a simple skeletal muscular structure. We have already prototyped a simple robotic walker from a single reconfigurable tetrahedron capable of tumbling and a more evolved 12Tetrahedral Walker, the Autonomous Landed Investigator (ALI), which has interior nodes for payload, more continuous motion, and is commandable through a user friendly interface. ALI is an EMS level mission concept which would allow autonomous in situ exploration of the lunar poles within the next decade. ALI would consist of one or more 12tetrahedral walkers capable of rapid locomotion with the many degrees of freedom and equipped for navigation in the unilluminated, inaccessible and thus largely unexplored rugged terrains where lunar resources are likely to be found: the Polar Regions. ALI walkers would act as roving reconnaissance teams for unexplored regions, analyzing samples along the way.

Functional renormalization group analysis of tensorial group field theories on Rd

NASA Astrophysics Data System (ADS)

Geloun, Joseph Ben; Martini, Riccardo; Oriti, Daniele

2016-07-01

Rank-d tensorial group field theories are quantum field theories (QFTs) defined on a group manifold G×d , which represent a nonlocal generalization of standard QFT and a candidate formalism for quantum gravity, since, when endowed with appropriate data, they can be interpreted as defining a field theoretic description of the fundamental building blocks of quantum spacetime. Their renormalization analysis is crucial both for establishing their consistency as quantum field theories and for studying the emergence of continuum spacetime and geometry from them. In this paper, we study the renormalization group flow of two simple classes of tensorial group field theories (TGFTs), defined for the group G =R for arbitrary rank, both without and with gauge invariance conditions, by means of functional renormalization group techniques. The issue of IR divergences is tackled by the definition of a proper thermodynamic limit for TGFTs. We map the phase diagram of such models, in a simple truncation, and identify both UV and IR fixed points of the RG flow. Encouragingly, for all the models we study, we find evidence for the existence of a phase transition of condensation type.

A cargo-sorting DNA robot.

PubMed

Thubagere, Anupama J; Li, Wei; Johnson, Robert F; Chen, Zibo; Doroudi, Shayan; Lee, Yae Lim; Izatt, Gregory; Wittman, Sarah; Srinivas, Niranjan; Woods, Damien; Winfree, Erik; Qian, Lulu

2017-09-15

Two critical challenges in the design and synthesis of molecular robots are modularity and algorithm simplicity. We demonstrate three modular building blocks for a DNA robot that performs cargo sorting at the molecular level. A simple algorithm encoding recognition between cargos and their destinations allows for a simple robot design: a single-stranded DNA with one leg and two foot domains for walking, and one arm and one hand domain for picking up and dropping off cargos. The robot explores a two-dimensional testing ground on the surface of DNA origami, picks up multiple cargos of two types that are initially at unordered locations, and delivers them to specified destinations until all molecules are sorted into two distinct piles. The robot is designed to perform a random walk without any energy supply. Exploiting this feature, a single robot can repeatedly sort multiple cargos. Localization on DNA origami allows for distinct cargo-sorting tasks to take place simultaneously in one test tube or for multiple robots to collectively perform the same task. Copyright © 2017, American Association for the Advancement of Science.

Superconductivity in doped fullerenes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hebard, A.F.

1992-11-01

While there is not complete agreement on the microscopic mechanism of superconductivity in alkali-metal-doped C[sub 60], further research may well lead to the production of analogous materials that lose resistance at even higher temperatures. Carbon 60 is a fascinating and arrestingly beautiful molecule. With 12 pentagonal and 20 hexagonal faces symmetrically arrayed in a soccer-ball-like structure that belongs to the icosahedral point group, I[sub h], its high symmetry alone invites special attention. The publication in September 1990 of a simple technique for manufacturing and concentrating macroscopic amounts of this new form of carbon announced to the scientific community that enablingmore » technology had arrived. Macroscopic amounts of C[sub 60] (and the higher fullerenes, such as C[sub 70] and C[sub 84]) can now be made with an apparatus as simple as an arc furnace powered with an arc welding supply. Accordingly, chemists, physicists and materials scientists have joined forces in an explosion of effort to explore the properties of this unusual molecular building block. 23 refs., 6 figs.« less

Incorporating residual temperature and specific humidity in predicting weather-dependent warm-season electricity consumption

NASA Astrophysics Data System (ADS)

Guan, Huade; Beecham, Simon; Xu, Hanqiu; Ingleton, Greg

2017-02-01

Climate warming and increasing variability challenges the electricity supply in warm seasons. A good quantitative representation of the relationship between warm-season electricity consumption and weather condition provides necessary information for long-term electricity planning and short-term electricity management. In this study, an extended version of cooling degree days (ECDD) is proposed for better characterisation of this relationship. The ECDD includes temperature, residual temperature and specific humidity effects. The residual temperature is introduced for the first time to reflect the building thermal inertia effect on electricity consumption. The study is based on the electricity consumption data of four multiple-street city blocks and three office buildings. It is found that the residual temperature effect is about 20% of the current-day temperature effect at the block scale, and increases with a large variation at the building scale. Investigation of this residual temperature effect provides insight to the influence of building designs and structures on electricity consumption. The specific humidity effect appears to be more important at the building scale than at the block scale. A building with high energy performance does not necessarily have low specific humidity dependence. The new ECDD better reflects the weather dependence of electricity consumption than the conventional CDD method.

Living with earthquakes - development and usage of earthquake-resistant construction methods in European and Asian Antiquity

NASA Astrophysics Data System (ADS)

Kázmér, Miklós; Major, Balázs; Hariyadi, Agus; Pramumijoyo, Subagyo; Ditto Haryana, Yohanes

2010-05-01

Earthquakes are among the most horrible events of nature due to unexpected occurrence, for which no spiritual means are available for protection. The only way of preserving life and property is applying earthquake-resistant construction methods. Ancient Greek architects of public buildings applied steel clamps embedded in lead casing to hold together columns and masonry walls during frequent earthquakes in the Aegean region. Elastic steel provided strength, while plastic lead casing absorbed minor shifts of blocks without fracturing rigid stone. Romans invented concrete and built all sizes of buildings as a single, unflexible unit. Masonry surrounding and decorating concrete core of the wall did not bear load. Concrete resisted minor shaking, yielding only to forces higher than fracture limits. Roman building traditions survived the Dark Ages and 12th century Crusader castles erected in earthquake-prone Syria survive until today in reasonably good condition. Concrete and steel clamping persisted side-by-side in the Roman Empire. Concrete was used for cheap construction as compared to building of masonry. Applying lead-encased steel increased costs, and was avoided whenever possible. Columns of the various forums in Italian Pompeii mostly lack steel fittings despite situated in well-known earthquake-prone area. Whether frequent recurrence of earthquakes in the Naples region was known to inhabitants of Pompeii might be a matter of debate. Seemingly the shock of the AD 62 earthquake was not enough to apply well-known protective engineering methods throughout the reconstruction of the city before the AD 79 volcanic catastrophe. An independent engineering tradition developed on the island of Java (Indonesia). The mortar-less construction technique of 8-9th century Hindu masonry shrines around Yogyakarta would allow scattering of blocks during earthquakes. To prevent dilapidation an intricate mortise-and-tenon system was carved into adjacent faces of blocks. Only the outermost layer was treated this way, the core of the shrines was made of simple rectangular blocks. The system resisted both in-plane and out-of-plane shaking quite well, as proven by survival of many shrines for more than a millennium, and by fracturing of blocks instead of displacement during the 2006 Yogyakarta earthquake. Systematic use or disuse of known earthquake-resistant techniques in any one society depends on the perception of earthquake risk and on available financial resources. Earthquake-resistant construction practice is significantly more expensive than regular construction. Perception is influenced mostly by short individual and longer social memory. If earthquake recurrence time is longer than the preservation of social memory, if damaging quakes fade into the past, societies commit the same construction mistakes again and again. Length of the memory is possibly about a generation's lifetime. Events occurring less frequently than 25-30 years can be readily forgotten, and the risk of recurrence considered as negligible, not worth the costs of safe construction practices. (Example of recurring flash floods in Hungary.) Frequent earthquakes maintain safe construction practices, like the Java masonry technique throughout at least two centuries, and like the Fachwerk tradition on Modern Aegean Samos throughout 500 years of political and technological development. (OTKA K67583)

7. Historic American Buildings Survey Verlin Berry, Photographer November 10, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. Historic American Buildings Survey Verlin Berry, Photographer November 10, 1977 FIRST FLOOR, VIEW OF PRESSED TIN CEILING WITH WOOD BLOCKING AT CROWN MOLDING - 111 West First Street (Commercial Building), Mishawaka, St. Joseph County, IN

Main-chain supramolecular block copolymers.

PubMed

Yang, Si Kyung; Ambade, Ashootosh V; Weck, Marcus

2011-01-01

Block copolymers are key building blocks for a variety of applications ranging from electronic devices to drug delivery. The material properties of block copolymers can be tuned and potentially improved by introducing noncovalent interactions in place of covalent linkages between polymeric blocks resulting in the formation of supramolecular block copolymers. Such materials combine the microphase separation behavior inherent to block copolymers with the responsiveness of supramolecular materials thereby affording dynamic and reversible materials. This tutorial review covers recent advances in main-chain supramolecular block copolymers and describes the design principles, synthetic approaches, advantages, and potential applications.

Estimating flow duration curve in the humid tropics: a disaggregation approach in Hawaiian catchments

NASA Astrophysics Data System (ADS)

Chris, Leong; Yoshiyuki, Yokoo

2017-04-01

Islands that are concentrated in developing countries have poor hydrological research data which contribute to stress on hydrological resources due to unmonitored human influence and negligence. As studies in islands are relatively young, there is a need to understand these stresses and influences by building block research specifically targeting islands. The flow duration curve (FDC) is a simple start up hydrological tool that can be used in initial studies of islands. This study disaggregates the FDC into three sections, top, middle and bottom and in each section runoff is estimated with simple hydrological models. The study is based on Hawaiian Islands, toward estimating runoff in ungauged island catchments in the humid tropics. Runoff estimations in the top and middle sections include using the Curve Number (CN) method and the Regime Curve (RC) respectively. The bottom section is presented as a separate study from this one. The results showed that for majority of the catchments the RC can be used for estimations in the middle section of the FDC. It also showed that in order for the CN method to make stable estimations, it had to be calibrated. This study identifies simple methodologies that can be useful for making runoff estimations in ungauged island catchments.

GENERAL VIEW OF TYPE HB54s (BUILDINGS T1088 TO T1093) & ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

GENERAL VIEW OF TYPE HB-54s (BUILDINGS T-1088 TO T-1093) & CONVERTED TYPE HB-54S (BUILDINGS T-1094 TO T-1096), LOOKING SOUTHWEST; BUILDING T-1088 AT LEFT, BUILDING T-1096 AT RIGHT - Fort McCoy, Building No. T-1096, South side of South Ninth Avenue, Block 10, Sparta, Monroe County, WI

Flexible Fabrication of Shape-Controlled Collagen Building Blocks for Self-Assembly of 3D Microtissues.

PubMed

Zhang, Xu; Meng, Zhaoxu; Ma, Jingyun; Shi, Yang; Xu, Hui; Lykkemark, Simon; Qin, Jianhua

2015-08-12

Creating artificial tissue-like structures that possess the functionality, specificity, and architecture of native tissues remains a big challenge. A new and straightforward strategy for generating shape-controlled collagen building blocks with a well-defined architecture is presented, which can be used for self-assembly of complex 3D microtissues. Collagen blocks with tunable geometries are controllably produced and released via a membrane-templated microdevice. The formation of functional microtissues by embedding tissue-specific cells into collagen blocks with expression of specific proteins is described. The spontaneous self-assembly of cell-laden collagen blocks into organized tissue constructs with predetermined configurations is demonstrated, which are largely driven by the synergistic effects of cell-cell and cell-matrix interactions. This new strategy would open up new avenues for the study of tissue/organ morphogenesis, and tissue engineering applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An easy access to 2-Amino-5,6-dihydro-3H-pyrimidin-4-one building blocks: the reaction under conventional and microwave conditions.

PubMed

Ostras, Konstantin S; Gorobets, Nikolay Yu; Desenko, Sergey M; Musatov, Vladimir I

2006-08-01

A new one-stage fast multicomponent synthesis of title compounds leads to products in 21-55% isolated yields under both conventional and microwave conditions. The primary amino group in the building blocks can be easily acylated by various usual electophilic agents that can be utilized in the synthesis of diverse heterocylic compounds libraries.

[Spatial distribution characteristics of urban potential population in Shenyang City based on QuickBird image and GIS].

PubMed

Li, Jun-Ying; Hu, Yuan-Man; Chen, Wei; Liu, Miao; Hu, Jian-Bo; Zhong, Qiao-Lin; Lu, Ning

2012-06-01

Population is the most active factor affecting city development. To understand the distribution characteristics of urban population is of significance for making city policy decisions and for optimizing the layout of various urban infrastructures. In this paper, the information of the residential buildings in Shenyang urban area was extracted from the QuickBird remote sensing images, and the spatial distribution characteristics of the population within the Third-Ring Road of the City were analyzed, according to the social and economic statistics data. In 2010, the population density in different types of residential buildings within the Third-Ring Road of the City decreased in the order of high-storey block, mixed block, mixed garden, old multi-storey building, high-storey garden, multi-storey block, multi-storey garden, villa block, shanty, and villa garden. The vacancy rate of the buildings within the Third-Ring Road was more than 30%, meaning that the real estate market was seriously overstocked. Among the five Districts of Shenyang City, Shenhe District had the highest potential population density, while Tiexi District and Dadong District had a lower one. The gravity center of the City and its five Districts was also analyzed, which could provide basic information for locating commercial facilities and planning city infrastructure.

Wrapping cytochrome c around single-wall carbon nanotube: engineered nanohybrid building blocks for infrared detection at high quantum efficiency

PubMed Central

Gong, Youpin; Liu, Qingfeng; Wilt, Jamie Samantha; Gong, Maogang; Ren, Shenqiang; Wu, Judy

2015-01-01

Biomolecule cytochrome c (Cty c), a small molecule of a chain of amino acids with extraordinary electron transport, was helically wrapped around a semiconductive single-wall carbon nanotube (s-SWCNT) to form a molecular building block for uncooled infrared detection with two uniquely designed functionalities: exciton dissociation to free charge carriers at the heterojunction formed on the s-SWCNT/Cty c interface and charge transport along the electron conducting chain of Cty c (acceptor) and hole conducting channel through s-SWCNT (donor). Such a design aims at addressing the long-standing challenges in exciton dissociation and charge transport in an SWCNT network, which have bottlenecked development of photonic SWCNT-based infrared detectors. Using these building blocks, uncooled s-SWCNT/Cyt c thin film infrared detectors were synthesized and shown to have extraordinary photoresponsivity up to 0.77 A W−1 due to a high external quantum efficiency (EQE) in exceeding 90%, which represents a more than two orders of magnitude enhancement than the best previously reported on CNT-based infrared detectors with EQE of only 1.72%. From a broad perspective, this work on novel s-SWCNT/Cyt c nanohybrid infrared detectors has developed a successful platform of engineered carbon nanotube/biomolecule building blocks with superior properties for optoelectronic applications. PMID:26066737

Wrapping cytochrome c around single-wall carbon nanotube: engineered nanohybrid building blocks for infrared detection at high quantum efficiency.

PubMed

Gong, Youpin; Liu, Qingfeng; Wilt, Jamie Samantha; Gong, Maogang; Ren, Shenqiang; Wu, Judy

2015-06-11

Biomolecule cytochrome c (Cty c), a small molecule of a chain of amino acids with extraordinary electron transport, was helically wrapped around a semiconductive single-wall carbon nanotube (s-SWCNT) to form a molecular building block for uncooled infrared detection with two uniquely designed functionalities: exciton dissociation to free charge carriers at the heterojunction formed on the s-SWCNT/Cty c interface and charge transport along the electron conducting chain of Cty c (acceptor) and hole conducting channel through s-SWCNT (donor). Such a design aims at addressing the long-standing challenges in exciton dissociation and charge transport in an SWCNT network, which have bottlenecked development of photonic SWCNT-based infrared detectors. Using these building blocks, uncooled s-SWCNT/Cyt c thin film infrared detectors were synthesized and shown to have extraordinary photoresponsivity up to 0.77 A W(-1) due to a high external quantum efficiency (EQE) in exceeding 90%, which represents a more than two orders of magnitude enhancement than the best previously reported on CNT-based infrared detectors with EQE of only 1.72%. From a broad perspective, this work on novel s-SWCNT/Cyt c nanohybrid infrared detectors has developed a successful platform of engineered carbon nanotube/biomolecule building blocks with superior properties for optoelectronic applications.

Intrinsic Folding Proclivities in Cyclic β-Peptide Building Blocks: Configuration and Heteroatom Effects Analyzed by Conformer-Selective Spectroscopy and Quantum Chemistry.

PubMed

Alauddin, Mohammad; Gloaguen, Eric; Brenner, Valérie; Tardivel, Benjamin; Mons, Michel; Zehnacker-Rentien, Anne; Declerck, Valérie; Aitken, David J

2015-11-09

This work describes the use of conformer-selective laser spectroscopy following supersonic expansion to probe the local folding proclivities of four-membered ring cyclic β-amino acid building blocks. Emphasis is placed on stereochemical effects as well as on the structural changes induced by the replacement of a carbon atom of the cycle by a nitrogen atom. The amide A IR spectra are obtained and interpreted with the help of quantum chemistry structure calculations. Results provide evidence that the building block with a trans-substituted cyclobutane ring has a predilection to form strong C8 hydrogen bonds. Nitrogen-atom substitution in the ring induces the formation of the hydrazino turn, with a related but distinct hydrogen-bonding network: the structure is best viewed as a bifurcated C8/C5 bond with the N heteroatom lone electron pair playing a significant acceptor role, which supports recent observations on the hydrazino turn structure in solution. Surprisingly, this study shows that the cis-substituted cyclobutane ring derivative also gives rise predominantly to a C8 hydrogen bond, although weaker than in the two former cases, a feature that is not often encountered for this building block. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microzonation of seismic risk in a low-rise Latin American city based on the macroseismic evaluation of the vulnerability of residential buildings: Colima city, México

NASA Astrophysics Data System (ADS)

Zobin, V. M.; Cruz-Bravo, A. A.; Ventura-Ramírez, F.

2010-06-01

A macroseismic methodology of seismic risk microzonation in a low-rise city based on the vulnerability of residential buildings is proposed and applied to Colima city, Mexico. The seismic risk microzonation for Colima consists of two elements: the mapping of residential blocks according to their vulnerability level and the calculation of an expert-opinion based damage probability matrix (DPM) for a given level of earthquake intensity and a given type of residential block. A specified exposure time to the seismic risk for this zonation is equal to the interval between two destructive earthquakes. The damage probability matrices were calculated for three types of urban buildings and five types of residential blocks in Colima. It was shown that only 9% of 1409 residential blocks are able to resist to the Modify Mercalli (MM) intensity VII and VIII earthquakes without significant damage. The proposed DPM-2007 is in good accordance with the experimental damage curves based on the macroseismic evaluation of 3332 residential buildings in Colima that was carried out after the 21 January 2003 intensity MM VII earthquake. This methodology and the calculated PDM-2007 curves may be applied also to seismic risk microzonation for many low-rise cities in Latin America, Asia, and Africa.

Advanced space system concepts and their orbital support needs (1980 - 2000). Volume 4: Detailed data. Part 2: Program plans and common support needs (a study of the commonality of space vehicle applications to future national needs

NASA Technical Reports Server (NTRS)

Bekey, I.; Mayer, H. L.; Wolfe, M. G.

1976-01-01

The methodology of alternate world future scenarios is utilized for selecting a plausible, though not advocated, set of future scenarios each of which results in a program plan appropriate for the respective environment. Each such program plan gives rise to different building block and technology requirements, which are analyzed for common need between the NASA and the DoD for each of the alternate world scenarios. An essentially invariant set of system, building block, and technology development plans is presented at the conclusion, intended to allow protection of most of the options for system concepts regardless of what the actual future world environment turns out to be. Thus, building block and technology needs are derived which support: (1) each specific world scenario; (2) all the world scenarios identified in this study; or (3) generalized scenarios applicable to almost any future environment. The output included in this volume consists of the building blocks, i.e.: transportation vehicles, orbital support vehicles, and orbital support facilities; the technology required to support the program plans; identification of their features which could support the DoD and NASA in common; and a complete discussion of the planning methodology.

Making Your Own Hollow Blocks. What We Make. Science and Technology Education in Philippine Society.

ERIC Educational Resources Information Center

Philippines Univ., Quezon City. Inst. for Science and Mathematics Education Development.

The procedures needed to make hollow blocks from palay hull, sawdust, soil, or sand are outlined in this module. Also outlined are the procedures needed to construct the wooden molds used to make the blocks. The hollow blocks can be used in building a one story house where the roof does not rest on the hollow block wall, an additional room to the…

Mapping from Space - Ontology Based Map Production Using Satellite Imageries

NASA Astrophysics Data System (ADS)

Asefpour Vakilian, A.; Momeni, M.

2013-09-01

Determination of the maximum ability for feature extraction from satellite imageries based on ontology procedure using cartographic feature determination is the main objective of this research. Therefore, a special ontology has been developed to extract maximum volume of information available in different high resolution satellite imageries and compare them to the map information layers required in each specific scale due to unified specification for surveying and mapping. ontology seeks to provide an explicit and comprehensive classification of entities in all sphere of being. This study proposes a new method for automatic maximum map feature extraction and reconstruction of high resolution satellite images. For example, in order to extract building blocks to produce 1 : 5000 scale and smaller maps, the road networks located around the building blocks should be determined. Thus, a new building index has been developed based on concepts obtained from ontology. Building blocks have been extracted with completeness about 83%. Then, road networks have been extracted and reconstructed to create a uniform network with less discontinuity on it. In this case, building blocks have been extracted with proper performance and the false positive value from confusion matrix was reduced by about 7%. Results showed that vegetation cover and water features have been extracted completely (100%) and about 71% of limits have been extracted. Also, the proposed method in this article had the ability to produce a map with largest scale possible from any multi spectral high resolution satellite imagery equal to or smaller than 1 : 5000.

Mapping from Space - Ontology Based Map Production Using Satellite Imageries

NASA Astrophysics Data System (ADS)

Asefpour Vakilian, A.; Momeni, M.

2013-09-01

Determination of the maximum ability for feature extraction from satellite imageries based on ontology procedure using cartographic feature determination is the main objective of this research. Therefore, a special ontology has been developed to extract maximum volume of information available in different high resolution satellite imageries and compare them to the map information layers required in each specific scale due to unified specification for surveying and mapping. ontology seeks to provide an explicit and comprehensive classification of entities in all sphere of being. This study proposes a new method for automatic maximum map feature extraction and reconstruction of high resolution satellite images. For example, in order to extract building blocks to produce 1 : 5000 scale and smaller maps, the road networks located around the building blocks should be determined. Thus, a new building index has been developed based on concepts obtained from ontology. Building blocks have been extracted with completeness about 83 %. Then, road networks have been extracted and reconstructed to create a uniform network with less discontinuity on it. In this case, building blocks have been extracted with proper performance and the false positive value from confusion matrix was reduced by about 7 %. Results showed that vegetation cover and water features have been extracted completely (100 %) and about 71 % of limits have been extracted. Also, the proposed method in this article had the ability to produce a map with largest scale possible from any multi spectral high resolution satellite imagery equal to or smaller than 1 : 5000.

Highly modular high-brightness diode laser system design for a wide application range

NASA Astrophysics Data System (ADS)

Fritsche, Haro; Kruschke, Bastian; Koch, Ralf; Ferrario, Fabio; Kern, Holger; Pahl, Ullrich; Ehm, Einar; Pflueger, Silke; Grohe, Andreas; Gries, Wolfgang

2015-03-01

For an economic production it is important to serve as many applications as possible while keeping the product variations minimal. We present our modular laser design, which is based on single emitters and various combining technics. In a first step we accept a reduction of the very high brightness of the single emitters by vertical stacking. Those emitters can be wavelength stabilized by an external resonator, providing the very same feedback to each of those laser diodes which leads to an output power of about 100W with BPP of <3.5 mm*mrad (FA) and <5 mm*mrad (SA). Further power scaling is accomplished by polarization and wavelength multiplexing yielding high optical efficiencies of more than 80% and results in about 500 W launched into a 100 μm fiber with 0.15 NA. Subsequently those building blocks can be stacked also by the very same dense spectral combing technique up to multi kW Systems without further reduction of the BPP. These "500W building blocks" are consequently designed in a way that without any system change new wavelengths can be implemented by only exchanging parts but without change of the production process. This design principal offers the option to adapt the wavelength of those blocks to any applications, from UV, visible into the far IR. From laser pumping and scientific applications to materials processing such as cutting and welding of copper aluminum or steel and also medical application. Operating at wavelengths between 900 nm and 1100 nm, these systems are mainly used in cutting and welding, but the technology can also be adapted to other wavelength ranges, such as 793 nm and 1530 nm. Around 1.5 μm the diodes are already successfully used for resonant pumping of Erbium lasers.[1] Furthermore, the fully integrated electronic concept allows addressing further applications, as it is capable of very short μs pulses up to cw mode operation by simple software commands.

17. A southward view of buildings #6B and #6 in ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. A southward view of buildings #6-B and #6 in the left background and buildings #5 (center) and #3 (right of center). - American Chain & Cable Company, East Princess Street (400 Block), York, York County, PA

Streambank Protection Guidelines,

DTIC Science & Technology

1983-10-01

the types of rubble suitable for dumping on an eroding bank include broken pavement, bricks, building blocks , slag , and quarry waste. Large flat slabs...not provide any long-termn protection. blocks , and house brick. I rfbiae omrilgbo akt Completed gabion revetment made from prefabricated baskets...prevent pressure buildup that could cause revetment failure. BLOCKS . Precast cellular blocks can be ypi i .,, p no- , ,,, ,hag ,.,.,,,,t

Rockfall vulnerability assessment for masonry buildings

NASA Astrophysics Data System (ADS)

Mavrouli, Olga

2015-04-01

The methodologies for the quantitative risk assessment vary in function of the application scale and the available data. For fragmental rockfalls, risk calculation requires data for the expected damage of the exposed elements due to potential rock block impacts with a range of trajectories, magnitudes and intensities. Although the procedures for the quantification of the rock block characteristics in terms of magnitude-frequency relationships are well established, there are few methodologies for the calculation of the vulnerability, and these are usually empirical or judgmental. The response of buildings to rock block impacts using analytical methods has been mainly realised so far for reinforced concrete buildings, and some fragility curves have been calculated with the results, indicating the potential damage for a range of rock block characteristics. Masonry buildings, as a common structural typology in mountainous areas, are in many cases impacted by rock blocks during rockfalls. Their response presents some peculiarities in comparison with reinforced-concrete structures given the non-homogeneity and variability of the compound materials (blocks and mortar), their orthotropy, low strength in tension, the statically indeterminate load-bearing system and the non-monolithic connections. To this purpose, analytical procedures which are specifically adapted to masonry structures should be used for the evaluation of the expected damage due to rock impacts. In this contribution we discuss the application of the analytical approach for the assessment of the expected damage in rockfall prone areas and the simulation assumptions that can be made concerning the materials, geometry, loading and the relevant simplifications. The amount of uncertainties introduced during their analytical simulation is high due to the dispersion of the data for material mechanical properties and the construction techniques and quality and thus a probabilistic assessment is suggested. The random nature of the rockfall as far as it concerns the magnitude and the intensity of the rock blocks can also be introduced using parametric analyses.

Highly Ordered Block Copolymer Templates for the Generation of Nanostructured Materials

NASA Astrophysics Data System (ADS)

Bhoje Gowd, E.; Nandan, Bhanu; Bigall, Nadja C.; Eychmuller, Alexander; Stamm, Manfred

2009-03-01

Among many different types of self-assembled materials, block copolymers have attracted immense interest for applications in nanotechnology. Block copolymer thin film can be used as a template for patterning of hard inorganic materials such as metal nanoparticles. In the present work, we demonstrate a new approach to fabricate highly ordered arrays of nanoscopic inorganic dots and wires using switchable block copolymer thin films. Various inorganic nanoparticles from a simple aqueous solution were directly deposited on the surface reconstructed block copolymer templates. The preferential interaction of the nanoparticles with one of the blocks is mainly responsible for the lateral distribution of the nanoparticles in addition to the capillary forces. Subsequent stabilization by UV-irradiation followed by pyrolysis in air at 450 ^oC removes the polymer to produce highly ordered metallic nanostructures. This method is highly versatile as the procedure used here is simple, eco-friendly and provides a facile approach to fabricate a broad range of nanoscaled architectures with tunable lateral spacing.

Design and synthesis of unnatural heparosan and chondroitin building blocks

PubMed Central

Bera, Smritilekha; Linhardt, Robert J.

2011-01-01

Triazole linked heparosan and chondroitin disaccharide and tetrasaccharide building blocks were synthesized in a stereoselective manner by applying a very efficient Copper Catalyzed Azide-Alkyne Cycloadditions (CuAAC) reaction of appropriately substituted azido-glucuronic acid and propargyluted N-acetyl glucosamine and N-acetyl galactosamine derivative respectively. The resulting suitably substituted tetrasaccharide analogs can be easily converted into azide and alkyne unit for further synthesis of higher oligosaccharide analogs. PMID:21438620

PBF Reactor Building (PER620). After lowering reactor vessel onto blocks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

PBF Reactor Building (PER-620). After lowering reactor vessel onto blocks, it is rolled on logs into PBF. Metal framework under vessel is handling device. Various penetrations in reactor bottom were for instrumentation, poison injection, drains. Large one, below center "manhole" was for primary coolant. Photographer: Larry Page. Date: February 13, 1970. INEEL negative no. 70-736 - Idaho National Engineering Laboratory, SPERT-I & Power Burst Facility Area, Scoville, Butte County, ID

11. VIEW OF INTERIOR OF BUILDING 220 FIRST FLOOR, CELL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. VIEW OF INTERIOR OF BUILDING 220 FIRST FLOOR, CELL BLOCK 'A' (SOLITARY CONFINEMENT CELL BLOCK), TYPICAL SOLITARY CONFINEMENT CELL. THE CELL SHOWN IN CENTER OF PHOTO, HAS A 2-1/2' THICK STEEL DOOR. THE CELL SHOWN IN THE LEFT OF PHOTO, HAS A 3/4' DIAMETER IRON GRILLE DOOR. - U.S. Naval Base, Pearl Harbor, Brig, Neville Way near Ninth Street at Marine Barracks, Pearl City, Honolulu County, HI

Advanced information processing system: Local system services

NASA Technical Reports Server (NTRS)

Burkhardt, Laura; Alger, Linda; Whittredge, Roy; Stasiowski, Peter

1989-01-01

The Advanced Information Processing System (AIPS) is a multi-computer architecture composed of hardware and software building blocks that can be configured to meet a broad range of application requirements. The hardware building blocks are fault-tolerant, general-purpose computers, fault-and damage-tolerant networks (both computer and input/output), and interfaces between the networks and the computers. The software building blocks are the major software functions: local system services, input/output, system services, inter-computer system services, and the system manager. The foundation of the local system services is an operating system with the functions required for a traditional real-time multi-tasking computer, such as task scheduling, inter-task communication, memory management, interrupt handling, and time maintenance. Resting on this foundation are the redundancy management functions necessary in a redundant computer and the status reporting functions required for an operator interface. The functional requirements, functional design and detailed specifications for all the local system services are documented.

Effector-Triggered Self-Replication in Coupled Subsystems.

PubMed

Komáromy, Dávid; Tezcan, Meniz; Schaeffer, Gaël; Marić, Ivana; Otto, Sijbren

2017-11-13

In living systems processes like genome duplication and cell division are carefully synchronized through subsystem coupling. If we are to create life de novo, similar control over essential processes such as self-replication need to be developed. Here we report that coupling two dynamic combinatorial subsystems, featuring two separate building blocks, enables effector-mediated control over self-replication. The subsystem based on the first building block shows only self-replication, whereas that based on the second one is solely responsive toward a specific external effector molecule. Mixing the subsystems arrests replication until the effector molecule is added, resulting in the formation of a host-effector complex and the liberation of the building block that subsequently engages in self-replication. The onset, rate and extent of self-replication is controlled by the amount of effector present. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Laboratory testing of a building envelope segment based on cellular concrete

NASA Astrophysics Data System (ADS)

Fořt, Jan; Pavlík, Zbyšek; Černý, Robert

2016-07-01

Hygrothermal performance of a building envelope based on cellular concrete blocks is studied in the paper. Simultaneously, the strain fields induced by the heat and moisture changes are monitored. The studied wall is exposed to the climatic load corresponding to the winter climatic conditions of the moderate year for Prague. The winter climatic exposure is chosen in order to simulate the critical conditions of the building structure from the point of view of material performance and temperature and humidity loading. The evaluation of hygrothermal performance of a researched wall is done on the basis of relative humidity and temperature profiles measured along the cross section of the cellular concrete blocks. Strain gauges are fixed on the wall surface in expected orientation of the blocks expansion. The obtained results show a good hygrothermal function of the analyzed cellular concrete wall and its insignificant strain.

Synthesis of Triamino Acid Building Blocks with Different Lipophilicities

PubMed Central

Maity, Jyotirmoy; Honcharenko, Dmytro; Strömberg, Roger

2015-01-01

To obtain different amino acids with varying lipophilicity and that can carry up to three positive charges we have developed a number of new triamino acid building blocks. One set of building blocks was achieved by aminoethyl extension, via reductive amination, of the side chain of ortnithine, diaminopropanoic and diaminobutanoic acid. A second set of triamino acids with the aminoethyl extension having hydrocarbon side chains was synthesized from diaminobutanoic acid. The aldehydes needed for the extension by reductive amination were synthesized from the corresponding Fmoc-L-2-amino fatty acids in two steps. Reductive amination of these compounds with Boc-L-Dab-OH gave the C4-C8 alkyl-branched triamino acids. All triamino acids were subsequently Boc-protected at the formed secondary amine to make the monomers appropriate for the N-terminus position when performing Fmoc-based solid-phase peptide synthesis. PMID:25876040

Tandem Repeat Proteins Inspired By Squid Ring Teeth

NASA Astrophysics Data System (ADS)

Pena-Francesch, Abdon

Proteins are large biomolecules consisting of long chains of amino acids that hierarchically assemble into complex structures, and provide a variety of building blocks for biological materials. The repetition of structural building blocks is a natural evolutionary strategy for increasing the complexity and stability of protein structures. However, the relationship between amino acid sequence, structure, and material properties of protein systems remains unclear due to the lack of control over the protein sequence and the intricacies of the assembly process. In order to investigate the repetition of protein building blocks, a recently discovered protein from squids is examined as an ideal protein system. Squid ring teeth are predatory appendages located inside the suction cups that provide a strong grasp of prey, and are solely composed of a group of proteins with tandem repetition of building blocks. The objective of this thesis is the understanding of sequence, structure and property relationship in repetitive protein materials inspired in squid ring teeth for the first time. Specifically, this work focuses on squid-inspired structural proteins with tandem repeat units in their sequence (i.e., repetition of alternating building blocks) that are physically cross-linked via beta-sheet structures. The research work presented here tests the hypothesis that, in these systems, increasing the number of building blocks in the polypeptide chain decreases the protein network defects and improves the material properties. Hence, the sequence, nanostructure, and properties (thermal, mechanical, and conducting) of tandem repeat squid-inspired protein materials are examined. Spectroscopic structural analysis, advanced materials characterization, and entropic elasticity theory are combined to elucidate the structure and material properties of these repetitive proteins. This approach is applied not only to native squid proteins but also to squid-inspired synthetic polypeptides that allow for a fine control of the sequence and network morphology. The results provided in this work establish a clear dependence between the repetitive building blocks, the network morphology, and the properties of squid-inspired repetitive protein materials. Increasing the number of tandem repeat units in SRT-inspired proteins led to more effective protein networks with superior properties. Through increasing tandem repetition and optimization of network morphology, highly efficient protein materials capable of withstanding deformations up to 400% of their original length, with MPa-GPa modulus, high energy absorption (50 MJ m-3), peak proton conductivity of 3.7 mS cm-1 (at pH 7, highest reported to date for biological materials), and peak thermal conductivity of 1.4 W m-1 K -1 (which exceeds that of most polymer materials) were developed. These findings introduce new design rules in the engineering of proteins based on tandem repetition and morphology control, and provide a novel framework for tailoring and optimizing the properties of protein-based materials.

Molecular Clusters: Nanoscale Building Blocks for Solid-State Materials.

PubMed

Pinkard, Andrew; Champsaur, Anouck M; Roy, Xavier

2018-04-17

The programmed assembly of nanoscale building blocks into multicomponent hierarchical structures is a powerful strategy for the bottom-up construction of functional materials. To develop this concept, our team has explored the use of molecular clusters as superatomic building blocks to fabricate new classes of materials. The library of molecular clusters is rich with exciting properties, including diverse functionalization, redox activity, and magnetic ordering, so the resulting cluster-assembled solids, which we term superatomic crystals (SACs), hold the promise of high tunability, atomic precision, and robust architectures among a diverse range of other material properties. Molecular clusters have only seldom been used as precursors for functional materials. Our team has been at the forefront of new developments in this exciting research area, and this Account focuses on our progress toward designing materials from cluster-based precursors. In particular, this Account discusses (1) the design and synthesis of molecular cluster superatomic building blocks, (2) their self-assembly into SACs, and (3) their resulting collective properties. The set of molecular clusters discussed herein is diverse, with different cluster cores and ligand arrangements to create an impressive array of solids. The cluster cores include octahedral M 6 E 8 and cubane M 4 E 4 (M = metal; E = chalcogen), which are typically passivated by a shell of supporting ligands, a feature upon which we have expanded upon by designing and synthesizing more exotic ligands that can be used to direct solid-state assembly. Building from this library, we have designed whole families of binary SACs where the building blocks are held together through electrostatic, covalent, or van der Waals interactions. Using single-crystal X-ray diffraction (SCXRD) to determine the atomic structure, a remarkable range of compositional variability is accessible. We can also use this technique, in tandem with vibrational spectroscopy, to ascertain features about the constituent superatomic building blocks, such as the charge of the cluster cores, by analysis of bond distances from the SCXRD data. The combination of atomic precision and intercluster interactions in these SACs produces novel collective properties, including tunable electrical transport, crystalline thermal conductivity, and ferromagnetism. In addition, we have developed a synthetic strategy to insert redox-active guests into the superstructure of SACs via single-crystal-to-single-crystal intercalation. This intercalation process allows us to tune the optical and electrical transport properties of the superatomic crystal host. These properties are explored using a host of techniques, including Raman spectroscopy, SQUID magnetometry, electrical transport measurements, electronic absorption spectroscopy, differential scanning calorimetry, and frequency-domain thermoreflectance. Superatomic crystals have proven to be both robust and tunable, representing a new method of materials design and architecture. This Account demonstrates how precisely controlling the structure and properties of nanoscale building blocks is key in developing the next generation of functional materials; several examples are discussed and detailed herein.

Building a Case for Blocks as Kindergarten Mathematics Learning Tools

ERIC Educational Resources Information Center

Kinzer, Cathy; Gerhardt, Kacie; Coca, Nicole

2016-01-01

Kindergarteners need access to blocks as thinking tools to develop, model, test, and articulate their mathematical ideas. In the current educational landscape, resources such as blocks are being pushed to the side and being replaced by procedural worksheets and academic "seat time" in order to address standards. Mathematics research…

Revisit Pattern Blocks to Develop Rational Number Sense

ERIC Educational Resources Information Center

Champion, Joe; Wheeler, Ann

2014-01-01

Pattern blocks are inexpensive wooden, foam, or plastic manipulatives developed in the 1960s to help students build an understanding of shapes, proportions, equivalence, and fractions (EDC 1968). The colorful collection of basic shapes in classic pattern block kits affords opportunities for amazing puzzle-like problem-solving tasks and for…

Forest Edge Regrowth Typologies in Southern Sweden-Relationship to Environmental Characteristics and Implications for Management.

PubMed

Wiström, Björn; Busse Nielsen, Anders

2017-07-01

After two major storms, the Swedish Transport Administration was granted permission in 2008 to expand the railroad corridor from 10 to 20 m from the rail banks, and to clear the forest edges in the expanded area. In order to evaluate the possibilities for managers to promote and control the species composition of the woody regrowth so that a forest edge with a graded profile develops over time, this study mapped the woody regrowth and environmental variables at 78 random sites along the 610-km railroad between Stockholm and Malmö four growing seasons after the clearing was implemented. Through different clustering approaches, dominant tree species to be controlled and future building block species for management were identified. Using multivariate regression trees, the most decisive environmental variables were identified and used to develop a regrowth typology and to calculate species indicator values. Five regrowth types and ten indicator species were identified along the environmental gradients of soil moisture, soil fertility, and altitude. Six tree species dominated the regrowth across the regrowth types, but clustering showed that if these were controlled by selective thinning, lower tree and shrub species were generally present so they could form the "building blocks" for development of a graded edge. We concluded that selective thinning targeted at controlling a few dominant tree species, here named Functional Species Control, is a simple and easily implemented management concept to promote a wide range of suitable species, because it does not require field staff with specialist taxonomic knowledge.

Programmable colloidal molecules from sequential capillarity-assisted particle assembly

PubMed Central

Ni, Songbo; Leemann, Jessica; Buttinoni, Ivo; Isa, Lucio; Wolf, Heiko

2016-01-01

The assembly of artificial nanostructured and microstructured materials which display structures and functionalities that mimic nature’s complexity requires building blocks with specific and directional interactions, analogous to those displayed at the molecular level. Despite remarkable progress in synthesizing “patchy” particles encoding anisotropic interactions, most current methods are restricted to integrating up to two compositional patches on a single “molecule” and to objects with simple shapes. Currently, decoupling functionality and shape to achieve full compositional and geometrical programmability remains an elusive task. We use sequential capillarity-assisted particle assembly which uniquely fulfills the demands described above. This is a new method based on simple, yet essential, adaptations to the well-known capillary assembly of particles over topographical templates. Tuning the depth of the assembly sites (traps) and the surface tension of moving droplets of colloidal suspensions enables controlled stepwise filling of traps to “synthesize” colloidal molecules. After deposition and mechanical linkage, the colloidal molecules can be dispersed in a solvent. The template’s shape solely controls the molecule’s geometry, whereas the filling sequence independently determines its composition. No specific surface chemistry is required, and multifunctional molecules with organic and inorganic moieties can be fabricated. We demonstrate the “synthesis” of a library of structures, ranging from dumbbells and triangles to units resembling bar codes, block copolymers, surfactants, and three-dimensional chiral objects. The full programmability of our approach opens up new directions not only for assembling and studying complex materials with single-particle-level control but also for fabricating new microscale devices for sensing, patterning, and delivery applications. PMID:27051882

Two new hybrid molybdenum arsenate derivative constructed from [As2Mo6O26]6- building: Synthesis, structural characterization and photocatalysis property

NASA Astrophysics Data System (ADS)

Zhang, Xiao; Luo, Xuan; Duan, Yuanling; Huang, Yanping; Zhang, Nanxi; Zhao, Liyan; Wu, Jie

2017-08-01

Two new inorganic-organic hybrid materials [Cu(enMe)2]2{(As2Mo6O26) [Cu(enMe)2]}·4H2O (1) and [As2Mo6(OH)2O24][Cu(H2O)2(phen)]2 (2) (enMe = 1,2'-propanediamine, phen = 1,10'-phenanthroline) based on [As2Mo6O26]6- building blocks, denoted as [As2Mo6], have been obtained by hydrothermal methods. 1 shows a 1-D straight chain structure constructed form [As2Mo6] building blocks and [Cu(enMe)2] complexes, and then extended to 3-D supramolecular network by lattice water via hydrogen bonds interactions. 2 exhibits a new 1-D covalent ribbon with large rectangular grids formed from [As2Mo6] building blocks connected by [Cu(H2O)2(phen)] complexes, then extended into 3-D supramolecular network via hydrogen bonds and π···π interactions. In additional, the photocatalytic activity for methylene blue degradation under visible-light irradiation of 2 was investigated.

Self-assembly: Misfits unite

NASA Astrophysics Data System (ADS)

Grason, Gregory M.

2017-12-01

The spontaneous assembly of particulate or molecular 'building blocks' into larger architectures underlies structure formation in many biological and synthetic materials. Shape frustration of ill-fitting blocks holds a surprising key to more regular assemblies.

Door in west wall of the center block, positioned near ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Door in west wall of the center block, positioned near the detached kitchen/bake house building. - Lazaretto Quarantine Station, Wanamaker Avenue and East Second Street, Essington, Delaware County, PA

A novel strategy for high-stability lithium sulfur batteries by in situ formation of polysulfide adsorptive-blocking layer

NASA Astrophysics Data System (ADS)

Jin, Liming; Li, Gaoran; Liu, Binhong; Li, Zhoupeng; Zheng, Junsheng; Zheng, Jim P.

2017-07-01

Lithium sulfur (Lisbnd S) batteries are one of the most promising energy storage devices owing to their high energy and power density. However, the shuttle effect as a key barrier hinders its practical application by resulting in low coulombic efficiency and poor cycling performance. Herein, a novel design of in situ formed polysulfide adsorptive-blocking layer (PAL) on the cathode surface was developed to tame the polysulfide shuttling and promote the cycling stability for Lisbnd S batteries. The PAL is consisted of La2S3, which is capable to chemically adsorb polysulfide via the strong interaction of Lasbnd S bond and Ssbnd S bond, and build an effective barrier against sulfur escaping. Moreover, the La2S3 is capable to suppress the crystallization of Li2S and promote the ion transfer, which contributes to the reduced internal resistance of batteries. Furthermore, the by-product LiNO3 simultaneously forms a stable anode solid and electrolyte interface to further inhibit the polysulfide shuttle. By this simple and convenient method, the resultant Lisbnd S batteries achieved exceptional cycling stability with an ultralow decay rate of 0.055% since the 10th cycle.

A crown-like heterometallic unit as the building block for a 3D In-Ge-S framework.

PubMed

Han, Xiaohui; Wang, Zhenqing; Xu, Jin; Liu, Dan; Wang, Cheng

2015-12-14

Supertetrahedral clusters are the most common building blocks in constructing Group 13/14/16 microporous metal chalcogenide materials while other types of clusters are yet scarcely explored. Herein, a new crown-like building unit [In3Ge3S16] has been obtained. The units assemble into a 3D framework [C6H14NO]4[In6Ge3S17]·1.5H2O (1) via a dual-connection mode and a SrSi2 (srs)-type topology could be achieved by treating each unit as a tri-connected node.

PERTS: A Prototyping Environment for Real-Time Systems

NASA Technical Reports Server (NTRS)

Liu, Jane W. S.; Lin, Kwei-Jay; Liu, C. L.

1993-01-01

PERTS is a prototyping environment for real-time systems. It is being built incrementally and will contain basic building blocks of operating systems for time-critical applications, tools, and performance models for the analysis, evaluation and measurement of real-time systems and a simulation/emulation environment. It is designed to support the use and evaluation of new design approaches, experimentations with alternative system building blocks, and the analysis and performance profiling of prototype real-time systems.

VLSI architecture for a Reed-Solomon decoder

NASA Technical Reports Server (NTRS)

Hsu, In-Shek (Inventor); Truong, Trieu-Kie (Inventor)

1992-01-01

A basic single-chip building block for a Reed-Solomon (RS) decoder system is partitioned into a plurality of sections, the first of which consists of a plurality of syndrome subcells each of which contains identical standard-basis finite-field multipliers that are programmable between 10 and 8 bit operation. A desired number of basic building blocks may be assembled to provide a RS decoder of any syndrome subcell size that is programmable between 10 and 8 bit operation.

Exploring endoperoxides as a new entry for the synthesis of branched azasugars

PubMed Central

Domeyer, Svenja; Bjerregaard, Mark; Johansson, Henrik

2017-01-01

A new class of nitrogen-containing endoperoxides were synthesised by a photochemical [4 + 2]-cycloaddition between a diene and singlet oxygen. The endoperoxides were dihydroxylated and protected to provide a series of endoperoxide building blocks for organic synthesis, with potential use as precursors for the synthesis of branched azasugars. Preliminary exploration of the chemistry of these building blocks provided access to a variety of derivatives including tetrahydrofurans, epoxides and protected amino-tetraols. PMID:28487758

Cascaded VLSI neural network architecture for on-line learning

NASA Technical Reports Server (NTRS)

Thakoor, Anilkumar P. (Inventor); Duong, Tuan A. (Inventor); Daud, Taher (Inventor)

1992-01-01

High-speed, analog, fully-parallel, and asynchronous building blocks are cascaded for larger sizes and enhanced resolution. A hardware compatible algorithm permits hardware-in-the-loop learning despite limited weight resolution. A computation intensive feature classification application was demonstrated with this flexible hardware and new algorithm at high speed. This result indicates that these building block chips can be embedded as an application specific coprocessor for solving real world problems at extremely high data rates.

Spontaneous self-assembly of a giant spherical metal-oxide Keplerate: addition of one building block induces "immediate" formation of the complementary one from a constitutional dynamic library.

PubMed

Schäffer, Christian; Todea, Ana Maria; Gouzerh, Pierre; Müller, Achim

2012-01-11

The addition of dinuclear {Mo(2)} units to a dynamic library containing molybdates results in the spontaneous self-assembly of a giant spherical metal-oxide species of the type {(Mo)Mo(5)}(12){Mo(2)}(30) while the required pentagonal {(Mo)Mo(5)} building blocks are "immediately" formed. This journal is © The Royal Society of Chemistry 2012

Fluorescence enhancement through the formation of a single-layer two-dimensional supramolecular organic framework and its application in highly selective recognition of picric acid.

PubMed

Zhang, Ying; Zhan, Tian-Guang; Zhou, Tian-You; Qi, Qiao-Yan; Xu, Xiao-Na; Zhao, Xin

2016-06-18

A two-dimensional (2D) supramolecular organic framework (SOF) has been constructed through the co-assembly of a triphenylamine-based building block and cucurbit[8]uril (CB[8]). Fluorescence turn-on of the non-emissive building block was observed upon the formation of the 2D SOF, which displayed highly selective and sensitive recognition of picric acid over a variety of nitroaromatics.

Cascaded VLSI neural network architecture for on-line learning

NASA Technical Reports Server (NTRS)

Duong, Tuan A. (Inventor); Daud, Taher (Inventor); Thakoor, Anilkumar P. (Inventor)

1995-01-01

High-speed, analog, fully-parallel and asynchronous building blocks are cascaded for larger sizes and enhanced resolution. A hardware-compatible algorithm permits hardware-in-the-loop learning despite limited weight resolution. A comparison-intensive feature classification application has been demonstrated with this flexible hardware and new algorithm at high speed. This result indicates that these building block chips can be embedded as application-specific-coprocessors for solving real-world problems at extremely high data rates.

Building blocks for the development of an interface for high-throughput thin layer chromatography/ambient mass spectrometric analysis: a green methodology.

PubMed

Cheng, Sy-Chyi; Huang, Min-Zong; Wu, Li-Chieh; Chou, Chih-Chiang; Cheng, Chu-Nian; Jhang, Siou-Sian; Shiea, Jentaie

2012-07-17

Interfacing thin layer chromatography (TLC) with ambient mass spectrometry (AMS) has been an important area of analytical chemistry because of its capability to rapidly separate and characterize the chemical compounds. In this study, we have developed a high-throughput TLC-AMS system using building blocks to deal, deliver, and collect the TLC plate through an electrospray-assisted laser desorption ionization (ELDI) source. This is the first demonstration of the use of building blocks to construct and test the TLC-MS interfacing system. With the advantages of being readily available, cheap, reusable, and extremely easy to modify without consuming any material or reagent, the use of building blocks to develop the TLC-AMS interface is undoubtedly a green methodology. The TLC plate delivery system consists of a storage box, plate dealing component, conveyer, light sensor, and plate collecting box. During a TLC-AMS analysis, the TLC plate was sent to the conveyer from a stack of TLC plates placed in the storage box. As the TLC plate passed through the ELDI source, the chemical compounds separated on the plate would be desorbed by laser desorption and subsequently postionized by electrospray ionization. The samples, including a mixture of synthetic dyes and extracts of pharmaceutical drugs, were analyzed to demonstrate the capability of this TLC-ELDI/MS system for high-throughput analysis.

Mussel-inspired nano-building block assemblies for mimicking extracellular matrix microenvironments with multiple functions.

PubMed

Wang, Zhenming; Jia, Zhanrong; Jiang, Yanan; Li, Pengfei; Han, Lu; Lu, Xiong; Ren, Fuzeng; Wang, Kefeng; Yuan, Huiping

2017-08-03

The assembly of nano-building blocks is an effective way to produce artificial extracellular matrix microenvironments with hierarchical micro/nano structures. However, it is hard to assemble different types of nano-building blocks, to form composite coatings with multiple functions, by traditional layer-by-layer (LbL) self-assembly methods. Inspired by the mussel adhesion mechanism, we developed polydopamine (PDA)-decorated bovine serum albumin microspheres (BSA-MS) and nano-hydroxyapatite (nano-HA), and assembled them to form bioactive coatings with micro/nano structures encapsulating bone morphogenetic protein-2 (BMP-2). First, PDA-decorated nano-HA (nano-pHA) was obtained by oxidative polymerization of dopamine on nano-HA. Second, BMP-2-encapsulated BSA microspheres were prepared through desolvation, and then were also decorated by PDA (pBSA-MS). Finally, the nano-pHA and pBSA-MS were assembled using the adhesive properties of PDA. Bone marrow stromal cell cultures and in vivo implantation, showed that the pHA/pBSA (BMP-2) coatings can promote cell adhesion, proliferation, and benefited for osteoinductivity. PDA decoration was also applied to assemble various functional nanoparticles, such as nano-HA, polystyrene, and Fe 3 O 4 nanoparticles. In summary, this study provides a novel strategy for the assembly of biofunctional nano-building blocks, which surpasses traditional LbL self-assembly of polyelectrolytes, and can find broad applications in bioactive agents delivery or multi-functional coatings.

Key Topics for High-Lift Research: A Joint Wind Tunnel/Flight Test Approach

NASA Technical Reports Server (NTRS)

Fisher, David; Thomas, Flint O.; Nelson, Robert C.

1996-01-01

Future high-lift systems must achieve improved aerodynamic performance with simpler designs that involve fewer elements and reduced maintenance costs. To expeditiously achieve this, reliable CFD design tools are required. The development of useful CFD-based design tools for high lift systems requires increased attention to unresolved flow physics issues. The complex flow field over any multi-element airfoil may be broken down into certain generic component flows which are termed high-lift building block flows. In this report a broad spectrum of key flow field physics issues relevant to the design of improved high lift systems are considered. It is demonstrated that in-flight experiments utilizing the NASA Dryden Flight Test Fixture (which is essentially an instrumented ventral fin) carried on an F-15B support aircraft can provide a novel and cost effective method by which both Reynolds and Mach number effects associated with specific high lift building block flows can be investigated. These in-flight high lift building block flow experiments are most effective when performed in conjunction with coordinated ground based wind tunnel experiments in low speed facilities. For illustrative purposes three specific examples of in-flight high lift building block flow experiments capable of yielding a high payoff are described. The report concludes with a description of a joint wind tunnel/flight test approach to high lift aerodynamics research.

Single-trabecula building block for large-scale finite element models of cancellous bone.

PubMed

Dagan, D; Be'ery, M; Gefen, A

2004-07-01

Recent development of high-resolution imaging of cancellous bone allows finite element (FE) analysis of bone tissue stresses and strains in individual trabeculae. However, specimen-specific stress/strain analyses can include effects of anatomical variations and local damage that can bias the interpretation of the results from individual specimens with respect to large populations. This study developed a standard (generic) 'building-block' of a trabecula for large-scale FE models. Being parametric and based on statistics of dimensions of ovine trabeculae, this building block can be scaled for trabecular thickness and length and be used in commercial or custom-made FE codes to construct generic, large-scale FE models of bone, using less computer power than that currently required to reproduce the accurate micro-architecture of trabecular bone. Orthogonal lattices constructed with this building block, after it was scaled to trabeculae of the human proximal femur, provided apparent elastic moduli of approximately 150 MPa, in good agreement with experimental data for the stiffness of cancellous bone from this site. Likewise, lattices with thinner, osteoporotic-like trabeculae could predict a reduction of approximately 30% in the apparent elastic modulus, as reported in experimental studies of osteoporotic femora. Based on these comparisons, it is concluded that the single-trabecula element developed in the present study is well-suited for representing cancellous bone in large-scale generic FE simulations.

Monitoring Thermal Performance of Hollow Bricks with Different Cavity Fillers in Difference Climate Conditions

NASA Astrophysics Data System (ADS)

Pavlík, Zbyšek; Jerman, Miloš; Fořt, Jan; Černý, Robert

2015-03-01

Hollow brick blocks have found widespread use in the building industry during the last decades. The increasing requirements to the thermal insulation properties of building envelopes given by the national standards in Europe led the brick producers to reduce the production of common solid bricks. Brick blocks with more or less complex systems of internal cavities replaced the traditional bricks and became dominant on the building ceramics market. However, contrary to the solid bricks where the thermal conductivity can easily be measured by standard methods, the complex geometry of hollow brick blocks makes the application of common techniques impossible. In this paper, a steady-state technique utilizing a system of two climatic chambers separated by a connecting tunnel for sample positioning is used for the determination of the thermal conductivity, thermal resistance, and thermal transmittance ( U value) of hollow bricks with the cavities filled by air, two different types of mineral wool, polystyrene balls, and foam polyurethane. The particular brick block is provided with the necessary temperature- and heat-flux sensors and thermally insulated in the tunnel. In the climatic chambers, different temperatures are set. After steady-state conditions are established in the measuring system, the effective thermal properties of the brick block are calculated using the measured data. Experimental results show that the best results are achieved with hydrophilic mineral wool as a cavity filler; the worst performance exhibits the brick block with air-filled cavities.

ETR BUILDING, TRA642. SOUTH SIDE VIEW INCLUDES SOUTH SIDES OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR BUILDING, TRA-642. SOUTH SIDE VIEW INCLUDES SOUTH SIDES OF ETR BUILDING (HIGH ROOF LINE); ELECTRICAL BUILDING (ONE-STORY, MADE OF PUMICE BLOCKS), TRA-648; AND HEAT EXCHANGER BUILDING (WITH BUILDING NUMBERS), TRA-644. NOTE PROJECTION OF ELECTRICAL BUILDING AT LEFT EDGE OF VIEW. CAMERA FACES NORTH. INL NEGATIVE NO. HD46-37-3. Mike Crane, Photographer, 4/2005 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Automatic design and manufacture of robotic lifeforms.

PubMed

Lipson, H; Pollack, J B

2000-08-31

Biological life is in control of its own means of reproduction, which generally involves complex, autocatalysing chemical reactions. But this autonomy of design and manufacture has not yet been realized artificially. Robots are still laboriously designed and constructed by teams of human engineers, usually at considerable expense. Few robots are available because these costs must be absorbed through mass production, which is justified only for toys, weapons and industrial systems such as automatic teller machines. Here we report the results of a combined computational and experimental approach in which simple electromechanical systems are evolved through simulations from basic building blocks (bars, actuators and artificial neurons); the 'fittest' machines (defined by their locomotive ability) are then fabricated robotically using rapid manufacturing technology. We thus achieve autonomy of design and construction using evolution in a 'limited universe' physical simulation coupled to automatic fabrication.

Biological materials by design.

PubMed

Qin, Zhao; Dimas, Leon; Adler, David; Bratzel, Graham; Buehler, Markus J

2014-02-19

In this topical review we discuss recent advances in the use of physical insight into the way biological materials function, to design novel engineered materials 'from scratch', or from the level of fundamental building blocks upwards and by using computational multiscale methods that link chemistry to material function. We present studies that connect advances in multiscale hierarchical material structuring with material synthesis and testing, review case studies of wood and other biological materials, and illustrate how engineered fiber composites and bulk materials are designed, modeled, and then synthesized and tested experimentally. The integration of experiment and simulation in multiscale design opens new avenues to explore the physics of materials from a fundamental perspective, and using complementary strengths from models and empirical techniques. Recent developments in this field illustrate a new paradigm by which complex material functionality is achieved through hierarchical structuring in spite of simple material constituents.

Preparation and magnetic properties of phthalocyanine-based carbon materials containing transition metals

NASA Astrophysics Data System (ADS)

Honda, Z.; Sato, S.; Hagiwara, M.; Kida, T.; Sakai, M.; Fukuda, T.; Kamata, N.

2016-07-01

A simple method for the preparation of bulk quantities of magnetic carbon materials, which contain uniformly dispersed transition metals (M = Fe, Co, Ni, and Cu) as the magnetic components, is presented. By using highly chlorinated metal phthalocyanine as the building block and potassium as the coupling reagent, phthalocyanine-based carbon materials (PBCMs) containing transition metals were obtained. Our experiments demonstrate the structure of these PBCMs consists of transition metals embedded in graphitic carbon that includes a square planar MN4 magnetic core and the Fe and Co-PBCM possess spontaneous magnetization at room temperature. In addition, carbon-coated transition metal particles were obtained by the Wurtz-type reaction with excess amount of potassium coupling agent. The large transition metal surface area and magnetization of these M-PBCMs are useful for spintronic and catalytic applications.

Physics of Intracellular Organization in Bacteria.

PubMed

Wingreen, Ned S; Huang, Kerwyn Casey

2015-01-01

With the realization that bacteria achieve exquisite levels of spatiotemporal organization has come the challenge of discovering the underlying mechanisms. In this review, we describe three classes of such mechanisms, each of which has physical origins: the use of landmarks, the creation of higher-order structures that enable geometric sensing, and the emergence of length scales from systems of chemical reactions coupled to diffusion. We then examine the diversity of geometric cues that exist even in cells with relatively simple geometries, and end by discussing both new technologies that could drive further discovery and the implications of our current knowledge for the behavior, fitness, and evolution of bacteria. The organizational strategies described here are employed in a wide variety of systems and in species across all kingdoms of life; in many ways they provide a general blueprint for organizing the building blocks of life.

The DIMA web resource--exploring the protein domain network.

PubMed

Pagel, Philipp; Oesterheld, Matthias; Stümpflen, Volker; Frishman, Dmitrij

2006-04-15

Conserved domains represent essential building blocks of most known proteins. Owing to their role as modular components carrying out specific functions they form a network based both on functional relations and direct physical interactions. We have previously shown that domain interaction networks provide substantially novel information with respect to networks built on full-length protein chains. In this work we present a comprehensive web resource for exploring the Domain Interaction MAp (DIMA), interactively. The tool aims at integration of multiple data sources and prediction techniques, two of which have been implemented so far: domain phylogenetic profiling and experimentally demonstrated domain contacts from known three-dimensional structures. A powerful yet simple user interface enables the user to compute, visualize, navigate and download domain networks based on specific search criteria. http://mips.gsf.de/genre/proj/dima

LEAPing on with language: An on-line language programme to support classroom teachers and parents of primary school children (aged 5-11 years).

PubMed

Clare Allen, M; Kendrick, Andrew; Archbold, Sue; Harrigan, Suzanne

2014-05-01

The Leaping on with Language programme provides a combination of strategies and activities to accelerate children's spoken language use from simple sentences to complex language. Using a conversational philosophy it expands the building blocks of language (vocabulary, grammar, speech), whilst emphasising the importance of developing independent social communication and acknowledging a child's developing self esteem and self identity between the ages of 4-11. Three pilot projects evaluated the programme with a total of 51 delegates. The outcomes were hugely positive. Changes in behaviour were reported from the 3rd pilot 1 month later. Comments regarding the length of training, practical strategies and more film clips were implemented. Leaping on with language is now a free to access resource available on line.

α-Unsubstituted Pyrroles by NHC-Catalyzed Three-Component Coupling: Direct Synthesis of a Versatile Atorvastatin Derivative.

PubMed

Fleige, Mirco; Glorius, Frank

2017-08-10

A practical one-pot cascade reaction protocol provides direct access to valuable 1,2,4-trisubstituted pyrroles. The process involves an N-heterocyclic carbene (NHC)-catalyzed Stetter-type hydroformylation using glycolaldehyde dimer as a novel C1 building-block, followed by a Paal-Knorr condensation with primary amines. The reaction makes use of simple and commercially available starting-materials and catalyst, an important feature regarding applicability and utility. Low catalyst loading under mild reaction conditions afforded a variety of 1,2,4-substituted pyrroles in a transition-metal-free reaction with high step economy and good yields. This methodology is applied in the synthesis of a versatile Atorvastatin precursor, in which a variety of modifications at the pyrrole core structure are possible. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

BILL-E: Robotic Platform for Locomotion and Manipulation of Lightweight Space Structures

NASA Technical Reports Server (NTRS)

Jenett, Benjamin; Cheung, Kenneth

2017-01-01

We describe a robotic platform for traversing and manipulating a modular 3D lattice structure. The robot is designed to operate within a specifically structured environment, which enables low numbers of degrees of freedom (DOF) compared to robots performing comparable tasks in an unstructured environment. This allows for simple controls, as well as low mass and cost. This approach, designing the robot relative to the local environment in which it operates, results in a type of robot we call a "relative robot." We describe a bipedal robot that can locomote across a periodic lattice structure, as well as being able to handle, manipulate, and transport building block parts that compose the lattice structure. Based on a general inchworm design, the robot has added functionality for traveling over and operating on a host structure.

Multiple pickering emulsions stabilized by microbowls.

PubMed

Nonomura, Yoshimune; Kobayashi, Naoto; Nakagawa, Naoki

2011-04-19

Some researchers have focused on the adsorption of solid particles at fluid-fluid interfaces and prepared emulsions and foams called "Pickering emulsions/foams". However, while several reports exist on simple spherical emulsions, few reports are available on the formation of more complex structures. Here, we show that holes on particle surfaces are a key factor in establishing the variety and complexity of mesoscale structures. Microbowls, which are hollow particles with holes on their surfaces, form multiple emulsions (water-in-oil-in-water and oil-in-water-in-oil emulsions) by simply mixing them with water and oil. Furthermore, stable potato-like or coffee-bean-like emulsions are also obtained, although nonspherical emulsions are usually unstable because of their larger interfacial energies. These findings are useful in designing the building blocks of complex supracolloidal systems for pharmaceutical, food, and cosmetic products. © 2011 American Chemical Society

Decarboxylative alkenylation

NASA Astrophysics Data System (ADS)

Edwards, Jacob T.; Merchant, Rohan R.; McClymont, Kyle S.; Knouse, Kyle W.; Qin, Tian; Malins, Lara R.; Vokits, Benjamin; Shaw, Scott A.; Bao, Deng-Hui; Wei, Fu-Liang; Zhou, Ting; Eastgate, Martin D.; Baran, Phil S.

2017-04-01

Olefin chemistry, through pericyclic reactions, polymerizations, oxidations, or reductions, has an essential role in the manipulation of organic matter. Despite its importance, olefin synthesis still relies largely on chemistry introduced more than three decades ago, with metathesis being the most recent addition. Here we describe a simple method of accessing olefins with any substitution pattern or geometry from one of the most ubiquitous and variegated building blocks of chemistry: alkyl carboxylic acids. The activating principles used in amide-bond synthesis can therefore be used, with nickel- or iron-based catalysis, to extract carbon dioxide from a carboxylic acid and economically replace it with an organozinc-derived olefin on a molar scale. We prepare more than 60 olefins across a range of substrate classes, and the ability to simplify retrosynthetic analysis is exemplified with the preparation of 16 different natural products across 10 different families.

Modular assembly of optical nanocircuits.

PubMed

Shi, Jinwei; Monticone, Francesco; Elias, Sarah; Wu, Yanwen; Ratchford, Daniel; Li, Xiaoqin; Alù, Andrea

2014-05-29

A key element enabling the microelectronic technology advances of the past decades has been the conceptualization of complex circuits with versatile functionalities as being composed of the proper combination of basic 'lumped' circuit elements (for example, inductors and capacitors). In contrast, modern nanophotonic systems are still far from a similar level of sophistication, partially because of the lack of modularization of their response in terms of basic building blocks. Here we demonstrate the design, assembly and characterization of relatively complex photonic nanocircuits by accurately positioning a number of metallic and dielectric nanoparticles acting as modular lumped elements. The nanoparticle clusters produce the desired spectral response described by simple circuit rules and are shown to be dynamically reconfigurable by modifying the direction or polarization of impinging signals. Our work represents an important step towards extending the powerful modular design tools of electronic circuits into nanophotonic systems.

Modular assembly of optical nanocircuits

NASA Astrophysics Data System (ADS)

Shi, Jinwei; Monticone, Francesco; Elias, Sarah; Wu, Yanwen; Ratchford, Daniel; Li, Xiaoqin; Alù, Andrea

2014-05-01

A key element enabling the microelectronic technology advances of the past decades has been the conceptualization of complex circuits with versatile functionalities as being composed of the proper combination of basic ‘lumped’ circuit elements (for example, inductors and capacitors). In contrast, modern nanophotonic systems are still far from a similar level of sophistication, partially because of the lack of modularization of their response in terms of basic building blocks. Here we demonstrate the design, assembly and characterization of relatively complex photonic nanocircuits by accurately positioning a number of metallic and dielectric nanoparticles acting as modular lumped elements. The nanoparticle clusters produce the desired spectral response described by simple circuit rules and are shown to be dynamically reconfigurable by modifying the direction or polarization of impinging signals. Our work represents an important step towards extending the powerful modular design tools of electronic circuits into nanophotonic systems.

Photochemical Approaches to Complex Chemotypes: Applications in Natural Product Synthesis

PubMed Central

2016-01-01

The use of photochemical transformations is a powerful strategy that allows for the formation of a high degree of molecular complexity from relatively simple building blocks in a single step. A central feature of all light-promoted transformations is the involvement of electronically excited states, generated upon absorption of photons. This produces transient reactive intermediates and significantly alters the reactivity of a chemical compound. The input of energy provided by light thus offers a means to produce strained and unique target compounds that cannot be assembled using thermal protocols. This review aims at highlighting photochemical transformations as a tool for rapidly accessing structurally and stereochemically diverse scaffolds. Synthetic designs based on photochemical transformations have the potential to afford complex polycyclic carbon skeletons with impressive efficiency, which are of high value in total synthesis. PMID:27120289

Strain-induced phase transition and electron spin-polarization in graphene spirals

PubMed Central

Zhang, Xiaoming; Zhao, Mingwen

2014-01-01

Spin-polarized triangular graphene nanoflakes (t-GNFs) serve as ideal building blocks for the long-desired ferromagnetic graphene superlattices, but they are always assembled to planar structures which reduce its mechanical properties. Here, by joining t-GNFs in a spiral way, we propose one-dimensional graphene spirals (GSs) with superior mechanical properties and tunable electronic structures. We demonstrate theoretically the unique features of electron motion in the spiral lattice by means of first-principles calculations combined with a simple Hubbard model. Within a linear elastic deformation range, the GSs are nonmagnetic metals. When the axial tensile strain exceeds an ultimate strain, however, they convert to magnetic semiconductors with stable ferromagnetic ordering along the edges. Such strain-induced phase transition and tunable electron spin-polarization revealed in the GSs open a new avenue for spintronics devices. PMID:25027550

Strain-induced phase transition and electron spin-polarization in graphene spirals.

PubMed

Zhang, Xiaoming; Zhao, Mingwen

2014-07-16

Spin-polarized triangular graphene nanoflakes (t-GNFs) serve as ideal building blocks for the long-desired ferromagnetic graphene superlattices, but they are always assembled to planar structures which reduce its mechanical properties. Here, by joining t-GNFs in a spiral way, we propose one-dimensional graphene spirals (GSs) with superior mechanical properties and tunable electronic structures. We demonstrate theoretically the unique features of electron motion in the spiral lattice by means of first-principles calculations combined with a simple Hubbard model. Within a linear elastic deformation range, the GSs are nonmagnetic metals. When the axial tensile strain exceeds an ultimate strain, however, they convert to magnetic semiconductors with stable ferromagnetic ordering along the edges. Such strain-induced phase transition and tunable electron spin-polarization revealed in the GSs open a new avenue for spintronics devices.

Electrophoretic deposition of fluorescent Cu and Au sheets for light-emitting diodes

NASA Astrophysics Data System (ADS)

Liu, Jiale; Wu, Zhennan; Li, Tingting; Zhou, Ding; Zhang, Kai; Sheng, Yu; Cui, Jianli; Zhang, Hao; Yang, Bai

2015-12-01

Electrophoretic deposition (EPD) is a conventional method for fabricating film materials from nanometer-sized building blocks, and exhibits the advantages of low-cost, high-efficiency, wide-range thickness adjustment, and uniform deposition. Inspired by the interest in the application of two-dimensional (2D) nanomaterials, the EPD technique has been recently extended to building blocks with 2D features. However, the studies are mainly focused on simplex building blocks. The utilization of multiplex building blocks is rarely reported. In this work, we demonstrate a controlled EPD of Cu and Au sheets, which are 2D assemblies of luminescent Cu and Au nanoclusters. Systematic investigations reveal that both the deposition efficiency and the thickness are determined by the lateral size of the sheets. For Cu sheets with a large lateral size, a high ζ-potential and strong face-to-face van der Waals interactions facilitate the deposition with high efficiency. However, for Au sheets, the small lateral size and ζ-potential limit the formation of a thick film. To solve this problem, the deposition dynamics are controlled by increasing the concentration of the Au sheets and adding acetone. This understanding permits the fabrication of a binary EPD film by the stepwise deposition of Cu and Au sheets, thus producing a luminescent film with both Cu green emission and Au red emission. A white light-emitting diode prototype with color coordinates (x, y) = (0.31, 0.36) is fabricated by employing the EPD film as a color conversion layer on a 365 nm GaN clip and further tuning the amount of deposited Cu and Au sheets.Electrophoretic deposition (EPD) is a conventional method for fabricating film materials from nanometer-sized building blocks, and exhibits the advantages of low-cost, high-efficiency, wide-range thickness adjustment, and uniform deposition. Inspired by the interest in the application of two-dimensional (2D) nanomaterials, the EPD technique has been recently extended to building blocks with 2D features. However, the studies are mainly focused on simplex building blocks. The utilization of multiplex building blocks is rarely reported. In this work, we demonstrate a controlled EPD of Cu and Au sheets, which are 2D assemblies of luminescent Cu and Au nanoclusters. Systematic investigations reveal that both the deposition efficiency and the thickness are determined by the lateral size of the sheets. For Cu sheets with a large lateral size, a high ζ-potential and strong face-to-face van der Waals interactions facilitate the deposition with high efficiency. However, for Au sheets, the small lateral size and ζ-potential limit the formation of a thick film. To solve this problem, the deposition dynamics are controlled by increasing the concentration of the Au sheets and adding acetone. This understanding permits the fabrication of a binary EPD film by the stepwise deposition of Cu and Au sheets, thus producing a luminescent film with both Cu green emission and Au red emission. A white light-emitting diode prototype with color coordinates (x, y) = (0.31, 0.36) is fabricated by employing the EPD film as a color conversion layer on a 365 nm GaN clip and further tuning the amount of deposited Cu and Au sheets. Electronic supplementary information (ESI) available: Additional experimental information, and SEM images of Cu EPD films. See DOI: 10.1039/c5nr06599b

Streambank Protection Guidelines for Landowners and Local Governments,

DTIC Science & Technology

1983-10-01

building blocks , slag , and quarry waste. UNCHE SON / / Large flat slabs should be broken up into /smaller pieces. Garbage, vegetation, scrap lumber...concrete blocks , and house brick. but will not provide any long-term protection. Preabrfirated commercial gabion basket. Completed gabion revetment made...prevent pressure buildup that could cause revetment failure. BLOCKS . Precast cellular blocks can be *,-’e : Typi.tal sa.d- e, .t bag r ’etment

44. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

44. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE COMPANY FACTORY AND WAREHOUSE AND DUBUQUE SEED COMPANY WAREHOUSE IN BACKGROUND. VIEW TO SOUTHWEST. - Dubuque Commercial & Industrial Buildings, Dubuque, Dubuque County, IA

43. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

43. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE COMPANY FACTORY AND WAREHOUSE AND DUBUQUE SEED COMPANY WAREHOUSE IN BACKGROUND. VIEW TO SOUTHWEST. - Dubuque Commercial & Industrial Buildings, Dubuque, Dubuque County, IA

42. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

42. RAILROAD TRACKS, WITH BISHOP'S BLOCK, MCFADDEN COFFEE AND SPICE COMPANY FACTORY AND WAREHOUSE AND DUBUQUE SEED COMPANY WAREHOUSE IN BACKGROUND. VIEW TO SOUTHWEST. - Dubuque Commercial & Industrial Buildings, Dubuque, Dubuque County, IA

12. SOUTHWEST VIEW OF BUILDING 25C (SUBSONIC AERODYNAMICS TEST FACILITY) ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. SOUTHWEST VIEW OF BUILDING 25C (SUBSONIC AERODYNAMICS TEST FACILITY) (1992). - Wright-Patterson Air Force Base, Area B, Buildings 25 & 24,10-foot & 20-foot Wind Tunnel Complex, Northeast side of block bounded by K, G, Third, & Fifth Streets, Dayton, Montgomery County, OH

Photogrammetric Recording and Reconstruction of Town Scale Models - the Case of the Plan-Relief of Strasbourg

NASA Astrophysics Data System (ADS)

Macher, H.; Grussenmeyer, P.; Landes, T.; Halin, G.; Chevrier, C.; Huyghe, O.

2017-08-01

The French collection of Plan-Reliefs, scale models of fortified towns, constitutes a precious testimony of the history of France. The aim of the URBANIA project is the valorisation and the diffusion of this Heritage through the creation of virtual models. The town scale model of Strasbourg at 1/600 currently exhibited in the Historical Museum of Strasbourg was selected as a case study. In this paper, the photogrammetric recording of this scale model is first presented. The acquisition protocol as well as the data post-processing are detailed. Then, the modelling of the city and more specially building blocks is investigated. Based on point clouds of the scale model, the extraction of roof elements is considered. It deals first with the segmentation of the point cloud into building blocks. Then, for each block, points belonging to roofs are identified and the extraction of chimney point clouds as well as roof ridges and roof planes is performed. Finally, the 3D parametric modelling of the building blocks is studied by considering roof polygons and polylines describing chimneys as input. In a future works section, the semantically enrichment and the potential usage scenarios of the scale model are envisaged.

School's Out, Let's Eat: FRAC's Guide to Using the Child and Adult Care Food Program (CACFP) to Expand Afterschool Opportunities for Children. The Building Blocks Project. Promoting Education and Child Development with Nutrition Resources.

ERIC Educational Resources Information Center

Wierwille, Jennifer; Parker, Lynn; Henchy, Geraldine; Driscoll, Christin M.; Tingling-Clemmons, Michele

The provision of quality before- and after-school child care is a major challenge facing educators. This guide from the Food Research and Action Center's Building Blocks Project provides information to providers of before and after school programs on using the federal Child and Adult Care Food Program (CACFP) to provide snacks and meals. Following…

Molecularly Defined Nanostructures Based on a Novel AAA-DDD Triple Hydrogen-Bonding Motif.

PubMed

Papmeyer, Marcus; Vuilleumier, Clément A; Pavan, Giovanni M; Zhurov, Konstantin O; Severin, Kay

2016-01-26

A facile and flexible method for the synthesis of a new AAA-DDD triple hydrogen-bonding motif is described. Polytopic supramolecular building blocks with precisely oriented AAA and DDD groups are thus accessible in few steps. These building blocks were used for the assembly of large macrocycles featuring four AAA-DDD interactions and a macrobicyclic complex with a total of six AAA-DDD interactions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Single crystalline Ge(1-x)Mn(x) nanowires as building blocks for nanoelectronics.

PubMed

van der Meulen, Machteld I; Petkov, Nikolay; Morris, Michael A; Kazakova, Olga; Han, Xinhai; Wang, Kang L; Jacob, Ajey P; Holmes, Justin D

2009-01-01

Magnetically doped Si and Ge nanowires have potential application in future nanowire spin-based devices. Here, we report a supercritical fluid method for producing single crystalline Mn-doped Ge nanowires with a Mn-doping concentration of between 0.5-1.0 atomic % that display ferromagnetism above 300 K and a superior performance with respect to the hole mobility of around 340 cm(2)/Vs, demonstrating the potential of using these nanowires as building blocks for electronic devices.

Data Type Registry - Cross Road Between Catalogs, Data And Semantics

NASA Astrophysics Data System (ADS)

Richard, S. M.; Zaslavsky, I.; Bristol, S.

2017-12-01

As more data become accessible online, the opportunity is increasing to improve search for information within datasets and for automating some levels of data integration. A prerequisite for these advances is indexing the kinds of information that are present in datasets and providing machine actionable descriptions of data structures. We are exploring approaches to enabling these capabilities in the EarthCube DigitalCrust and Data Discovery Hub Building Block projects, building on the Data type registry (DTR) workgroup activity in the Research Data Alliance. We are prototyping a registry implementation using the CNRI Cordra platform and API to enable 'deep registration' of datasets for building hydrogeologic models of the Earth's Crust, and executing complex science scenarios for river chemistry and coral bleaching data. These use cases require the ability to respond to queries such as: What are properties of Entity X; What entities include property Y (or L, M, N…), and What DataTypes are about Entity X and include property Y. Development of the registry to enable these capabilities requires more in-depth metadata than is commonly available, so we are also exploring approaches to analyzing simple tabular data to automate recognition of entities and properties, and assist users with establishing semantic mappings to data integration vocabularies. This poster will review the current capabilities and implementation of a data type registry.

4. Historic American Buildings Survey Nathaniel R. Ewan, Photographer January ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. Historic American Buildings Survey Nathaniel R. Ewan, Photographer January 6, 1939 INTERIOR - END CARRIAGE 'BLOCK AND DOGS' - McMurtry's Saw Mill, Hardscrabble Road, Basking Ridge, Somerset County, NJ

Historic American Buildings Survey PHOTOCOPY OF MEASURED DRAWING BY DIETER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Historic American Buildings Survey PHOTOCOPY OF MEASURED DRAWING BY DIETER SENGLER, 1964 CROSS SECTION AND ORIGINAL JACKSON BOULEVARD ELEVATION - Monadnock Block, 53 West Jackson Boulevard, Chicago, Cook County, IL

Modular Assembly of Hierarchically Structured Polymers

NASA Astrophysics Data System (ADS)

Leophairatana, Porakrit

The synthesis of macromolecules with complex yet highly controlled molecular architectures has attracted significant attention in the past few decades due to the growing demand for specialty polymers that possess novel properties. Despite recent efforts, current synthetic routes lack the ability to control several important architectural variables while maintaining low polydispersity index. This dissertation explores a new synthetic scheme for the modular assembly of hierarchically structured polymers (MAHP) that allows virtually any complex polymer to be assembled from a few basic molecular building blocks using a single common coupling chemistry. Complex polymer structures can be assembled from a molecular toolkit consisting of (1) copper-catalyzed azide-alkyne cycloaddition (CuAAC), (2) linear heterobifunctional macromonomers, (3) a branching heterotrifunctional molecule, (4) a protection/deprotection strategy, (5) "click" functional solid substrates, and (6) functional and responsive polymers. This work addresses the different challenges that emerged during the development of this synthetic scheme, and presents strategies to overcome those challenges. Chapter 3 investigates the alkyne-alkyne (i.e. Glaser) coupling side reactions associated with the atom transfer radical polymerization (ATRP) synthesis of alkyne-functional macromonomers, as well as with the CuAAC reaction of alkyne functional building blocks. In typical ATRP synthesis of unprotected alkyne functional polymers, Glaser coupling reactions can significantly compromise the polymer functionality and undermine the success of subsequent click reactions in which the polymers are used. Two strategies are reported that effectively eliminate these coupling reactions: (1) maintaining low temperature post-ATRP upon exposure to air, followed by immediate removal of copper catalyst; and (2) adding excess reducing agents post-ATRP, which prevents the oxidation of Cu(I) catalyst required by the Glaser coupling mechanism. Post-ATRP Glaser coupling was also influenced by the ATRP synthesis ligand used. The order of ligand activity for catalyzing Glaser coupling was: linear bidentate > tridentate > tetradentate. Glaser coupling can also occur for alkynes held under CuAAC reaction conditions but again can be eliminated by adding appropriate reducing agents. With the strategy presented in Chapter 3, alkyne-terminated polymers of high-functionality were produced without the need for alkyne protecting groups. These "click" functional building blocks were employed to investigate the overall efficiency of the CuAAC "click" coupling reactions between alkyne- and azide-terminated macromonomers as discussed in Chapter 4. Quantitative convolution modeling of the entire molecular weight distribution post-CuAAC indicates a CuAAC efficiency of about 94% and an azide substitution efficiency of >99%. However, incomplete functionality of the azide-terminated macromonomer (˜92%) proves to be the largest factor compromising the overall efficacy of the coupling reactions, and is attributed primarily to the loss of bromine functionality during synthesis by ATRP. To address this issue, we discuss in Chapter 6 the development of a new set of molecular building blocks consisting of alkyne functional substrates and heterobifunctional degradable linkers that allow the growth and subsequent detachment of polymers from the solid substrate. Complex polymeric structures are created by progressive cycles of CuAAC and deprotection reactions that add building blocks to the growing polymer chain ends. We demonstrate that these building blocks were completely stable under both CuAAC and deprotection reaction conditions. Since the desired product is covalently bound to the solid surface, the unreacted monomers/macromonomers and by-products (i.e. non-functional building blocks) can be easily separated from the product via removal of the polymer-tethered solid substrate in one step. Chapter 5 discusses how MAHP was employed to prepare a variety of hierarchically structured polymers and copolymers with controlled branching architectures. alpha-azido,o-TIPS-alkyne-heterobifunctional and heterotrifunctional building blocks were first prepared via ATRP and organic synthesis. Preliminary NMR and SEC studies demonstrated that these building blocks all satisfied the criteria necessary for MAHP: (1) the TIPS protecting group is stable during ATRP and CuAAC, (2) the "click" functionality is completely regenerated during the deprotection step, and (3) the CuAAC reaction of branching macromonomers is quantitative (>94%). To demonstrate the concept, poly(n-butyl acrylate)-b-dipolystyrene- b-dipoly(tert-butyl acrylate) penta-block branching copolymacromer was prepared via MAHP and quantitively characterized with SEC and NMR. (Abstract shortened by ProQuest.).

Development of volume deposition on cast iron by additive manufacturing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sridharan, Niyanth; Dehoff, Ryan R.; Jordan, Brian H.

2016-11-10

ORNL partnered with Cummins to demonstrate the feasibility of using additive manufacturing techniques to help develop repair techniques for refurbished cast iron engine blocks. Cummins is interested in the refurbished engine business due to the increased cost savings and reduced emissions. It is expected that by refurbishing engines could help reduce the green house gas emissions by as much as 85%. Though such repair techniques are possible in principle there has been no major industry in the automotive sector that has deployed this technology. Therefore phase-1 would seek to evaluate the feasibility of using the laser directed energy deposition techniquemore » to repair cast iron engine blocks. The objective of the phase-1 would be to explore various strategies and understand the challenges involved. During phase-1 deposits were made using Inconel-718, Nickel, Nr-Cr-B braze filler. Inconel 718 builds showed significant cracking in the heat-affected zone in the cast iron. Nickel was used to reduce the cracking in the cast iron substrate, however the Ni builds did not wet the substrate sufficiently resulting in poor dimensional tolerance. In order to increase wetting the Ni was alloyed with the Ni-Cr-B braze to decrease the surface tension of Ni. This however resulted in significant cracks in the build due to shrinkage stresses associated with multiple thermal cycling. Hence to reduce the residual stresses in the builds the DMD-103D equipment was modified and the cast iron block was pre heated using cartridge heaters. Inconel-718 alloyed with Ni was deposited on the engine block. The pre-heated deposits showed a reduced susceptibility to cracking. If awarded the phase-2 of the project would aim to develop process parameters to achieve a crack free deposit engine block.« less

Where are lifesaving automated external defibrillators located and how hard is it to find them in a large urban city?

PubMed Central

Leung, Alison C.; Asch, David A.; Lozada, Kirkland N.; Saynisch, Olivia B.; Asch, Jeremy M.; Becker, Nora; Griffis, Heather M.; Shofer, Frances; Hershey, John C.; Hill, Shawndra; Branas, Charles C.; Nichol, Graham; Becker, Lance B.; Merchant, Raina M.

2013-01-01

Objectives Automated external defibrillators (AEDs) are lifesaving, but little is known about where they are located or how to find them. We sought to locate AEDs in high employment areas of Philadelphia and characterize the process of door-to-door surveying to identify these devices. Methods Block groups representing approximately the top 3rd of total primary jobs in Philadelphia were identified using the US Census Local Employment Dynamics database. All buildings within these block groups were surveyed during regular working hours over six weeks during July-August 2011. Buildings were characterized as publically accessible or inaccessible. For accessible buildings, address, location type, and AED presence were collected. Total devices, location description and prior use were gathered in locations with AEDs. Process information (total people contacted, survey duration) was collected for all buildings. Results Of 1420 buildings in 17 block groups, 949 (67%) were accessible, but most 834 (88%) did not have an AED. 283 AEDs were reported in 115 buildings (12%). 81 (29%) were validated through visualization and 68 (24%) through photo because employees often refused access. In buildings with AEDs, several employees (median 2; range 1–8) were contacted to ascertain information, which required several minutes (mean 4; range 1–55). Conclusions Door-to-door surveying is a feasible, but time-consuming method for identifying AEDs in high employment areas. Few buildings reported having AEDs and few permitted visualization, which raises concerns about AED access. To improve cardiac arrest outcomes, efforts are needed to improve the availability of AEDs, awareness of their location and access to them. PMID:23357702

Where are lifesaving automated external defibrillators located and how hard is it to find them in a large urban city?

PubMed

Leung, Alison C; Asch, David A; Lozada, Kirkland N; Saynisch, Olivia B; Asch, Jeremy M; Becker, Nora; Griffis, Heather M; Shofer, Frances; Hershey, John C; Hill, Shawndra; Branas, Charles C; Nichol, Graham; Becker, Lance B; Merchant, Raina M

2013-07-01

Automated external defibrillators (AEDs) are lifesaving, but little is known about where they are located or how to find them. We sought to locate AEDs in high employment areas of Philadelphia and characterize the process of door-to-door surveying to identify these devices. Block groups representing approximately the top 3rd of total primary jobs in Philadelphia were identified using the US Census Local Employment Dynamics database. All buildings within these block groups were surveyed during regular working hours over six weeks during July-August 2011. Buildings were characterized as publically accessible or inaccessible. For accessible buildings, address, location type, and AED presence were collected. Total devices, location description and prior use were gathered in locations with AEDs. Process information (total people contacted, survey duration) was collected for all buildings. Of 1420 buildings in 17 block groups, 949 (67%) were accessible, but most 834 (88%) did not have an AED. 283 AEDs were reported in 115 buildings (12%). 81 (29%) were validated through visualization and 68 (24%) through photo because employees often refused access. In buildings with AEDs, several employees (median 2; range 1-8) were contacted to ascertain information, which required several minutes (mean 4; range 1-55). Door-to-door surveying is a feasible, but time-consuming method for identifying AEDs in high employment areas. Few buildings reported having AEDs and few permitted visualization, which raises concerns about AED access. To improve cardiac arrest outcomes, efforts are needed to improve the availability of AEDs, awareness of their location and access to them. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Properties of Clay for Ceramics with Rock Waste for Production Structural Block by Pressing and Firing

NASA Astrophysics Data System (ADS)

Cerqueira, N. A.; Choe, D.; Alexandre, J.; Azevedo, A. R. G.; Xavier, C. G.; Souza, V. B.

Building work requires optimization of materials and labor, so that the execution of its subsystems contribute to the quality, reduce costs, decrease waste in buildings, productivity, practicality and especially agility. Thus, the fitting blocks can contribute in this direction. This work therefore consists of physical characterization (determination of fitness levels, grain size and bulk density), chemical (EDX) and thermal (DTA and TGA) sample clay Campos dos Goytacazes-RJ and waste rock ornamental Cachoeiro de Itapemirim-ES, to verify potential for producing red ceramic blocks, pressed and burned, male and female type. The output of block will be with different pe rcentages of incorporation of residues of ornamental rocks (0%, 5% and 10%). With the results obtained, it was found that the raw materials under consideration has the potential for application in the production of ceramic articles.

Monolithic THz Frequency Multipliers

NASA Technical Reports Server (NTRS)

Erickson, N. R.; Narayanan, G.; Grosslein, R. M.; Martin, S.; Mehdi, I.; Smith, P.; Coulomb, M.; DeMartinez, G.

2001-01-01

Frequency multipliers are required as local oscillator sources for frequencies up to 2.7 THz for FIRST and airborne applications. Multipliers at these frequencies have not previously been demonstrated, and the object of this work was to show whether such circuits are really practical. A practical circuit is one which not only performs as well as is required, but also can be replicated in a time that is feasible. As the frequency of circuits is increased, the difficulties in fabrication and assembly increase rapidly. Building all of the circuit on GaAs as a monolithic circuit is highly desirable to minimize the complexity of assembly, but at the highest frequencies, even a complete monolithic circuit is extremely small, and presents serious handling difficulty. This is compounded by the requirement for a very thin substrate. Assembly can become very difficult because of handling problems and critical placement. It is very desirable to make the chip big enough to that it can be seen without magnification, and strong enough that it may be picked up with tweezers. Machined blocks to house the chips present an additional challenge. Blocks with complex features are very expensive, and these also imply very critical assembly of the parts. It would be much better if the features in the block were as simple as possible and non-critical to the function of the chip. In particular, grounding and other electrical interfaces should be done in a manner that is highly reproducible.

Grasping with the eyes of your hands: hapsis and vision modulate hand preference.

PubMed

Stone, Kayla D; Gonzalez, Claudia L R

2014-02-01

Right-hand preference has been demonstrated for visually guided reaching and grasping. Grasping, however, requires the integration of both visual and haptic cues. To what extent does vision influence hand preference for grasping? Is there a hand preference for haptically guided grasping? Two experiments were designed to address these questions. In Experiment 1, individuals were tested in a reaching-to-grasp task with vision (sighted condition) and with hapsis (blindfolded condition). Participants were asked to put together 3D models using building blocks scattered on a tabletop. The models were simple, composed of ten blocks of three different shapes. Starting condition (Vision-First or Hapsis-First) was counterbalanced among participants. Right-hand preference was greater in visually guided grasping but only in the Vision-First group. Participants who initially built the models while blindfolded (Hapsis-First group) used their right hand significantly less for the visually guided portion of the task. To investigate whether grasping using hapsis modifies subsequent hand preference, participants received an additional haptic experience in a follow-up experiment. While blindfolded, participants manipulated the blocks in a container for 5 min prior to the task. This additional experience did not affect right-hand use on visually guided grasping but had a robust effect on haptically guided grasping. Together, the results demonstrate first that hand preference for grasping is influenced by both vision and hapsis, and second, they highlight how flexible this preference could be when modulated by hapsis.

Dorello's Canal for Laymen: A Lego-Like Presentation.

PubMed

Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

2012-06-01

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students.

Dorello's Canal for Laymen: A Lego-Like Presentation

PubMed Central

Ezer, Haim; Banerjee, Anirban Deep; Thakur, Jai Deep; Nanda, Anil

2012-01-01

Objective Dorello's canal was first described by Gruber in 1859, and later by Dorello. Vail also described the anatomy of Dorello's canal. In the preceding century, Dorello's canal was clinically important, in understanding sixth nerve palsy and nowadays it is mostly important for skull base surgery. The understanding of the three dimensional anatomy, of this canal is very difficult to understand, and there is no simple explanation for its anatomy and its relationship with adjacent structures. We present a simple, Lego-like, presentation of Dorello's canal, in a stepwise manner. Materials and Methods Dorello's canal was dissected in five formalin-fixed cadaver specimens (10 sides). The craniotomy was performed, while preserving the neural and vascular structures associated with the canal. A 3D model was created, to explain the canal's anatomy. Results Using the petrous pyramid, the sixth nerve, the cavernous sinus, the trigeminal ganglion, the petorclival ligament and the posterior clinoid, the three-dimensional structure of Dorello's canal was defined. This simple representation aids in understanding the three dimensional relationship of Dorello's canal to its neighboring structures. Conclusion Dorello's canal with its three dimensional structure and relationship to its neighboring anatomical structures could be reconstructed using a few anatomical building blocks. This method simplifies the understanding of this complex anatomical structure, and could be used for teaching purposes for aspiring neurosurgeons, and anatomy students. PMID:23730547

Evaluation of Sunshine Duration around a Building in an Urban Area

NASA Astrophysics Data System (ADS)

Kang, J. E.; Kim, J.

2017-12-01

In this study, sunshine duration around a building in a building-congested district in Busan, Korea was analyzed using a numerical model. This model considers sunshine duration blocking caused by topography and buildings and it is properly applicable to evaluation of sunshine duration environment in urban areas. The 2 km Í 2 km area where the building with 45-m height was located at the center was selected as a target area. We selected the target period from December 21 to December 23, 2015, considering the winter solstice (December 22, 2015) when it is expected to have the largest effect of sunshine blocking due to buildings. We validated the calculated solar altitude and azimuth angles against those provided by Korea astronomy and space science institute (KASI) and the calculated results gave very good agreement with those provided by KASI. Topography and buildings used as the input data of the model were constructed using a geographic information system (GIS) data. In order to analyze, in detail, the change in sunshine duration caused by the construction of the building, the sunshine duration on the roof and walls (eastern, western, southern, northern side) were investigated before and after the construction.

Synthetic fermentation of bioactive non-ribosomal peptides without organisms, enzymes or reagents

NASA Astrophysics Data System (ADS)

Huang, Yi-Lin; Bode, Jeffrey W.

2014-10-01

Microbial fermentation can rapidly provide potent compounds that can be easily screened for biological activity, and the active components can be isolated. Its success in drug discovery has inspired extensive efforts to modulate and control the products. In this Article, we document a ‘synthetic fermentation’ of bioactive, unnatural peptides ‘grown’ from small building blocks in water using amide-forming ligations. No organisms, enzymes or reagents are needed. The sequences, structures and compositions of the products can be modulated by adjusting the building blocks and conditions. No specialized knowledge of organic chemistry or handling of toxic material is required to produce complex organic molecules. The ‘fermentations’ can be conducted in arrays and screened for biological activity without isolation or workup. As a proof-of-concept, about 6,000 unnatural peptides were produced from just 23 building blocks, from which a hepatitis C virus NS3/4A protease inhibitor with a half-maximum inhibitory concentration of 1.0 μM was identified and characterized.

A triaxial supramolecular weave

NASA Astrophysics Data System (ADS)

Lewandowska, Urszula; Zajaczkowski, Wojciech; Corra, Stefano; Tanabe, Junki; Borrmann, Ruediger; Benetti, Edmondo M.; Stappert, Sebastian; Watanabe, Kohei; Ochs, Nellie A. K.; Schaeublin, Robin; Li, Chen; Yashima, Eiji; Pisula, Wojciech; Müllen, Klaus; Wennemers, Helma

2017-11-01

Despite recent advances in the synthesis of increasingly complex topologies at the molecular level, nano- and microscopic weaves have remained difficult to achieve. Only a few diaxial molecular weaves exist—these were achieved by templation with metals. Here, we present an extended triaxial supramolecular weave that consists of self-assembled organic threads. Each thread is formed by the self-assembly of a building block comprising a rigid oligoproline segment with two perylene-monoimide chromophores spaced at 18 Å. Upon π stacking of the chromophores, threads form that feature alternating up- and down-facing voids at regular distances. These voids accommodate incoming building blocks and establish crossing points through CH-π interactions on further assembly of the threads into a triaxial woven superstructure. The resulting micrometre-scale supramolecular weave proved to be more robust than non-woven self-assemblies of the same building block. The uniform hexagonal pores of the interwoven network were able to host iridium nanoparticles, which may be of interest for practical applications.

Morphology-Controlled Synthesis and Metalation of Porphyrin Nanoparticles with Enhanced Photocatalytic Performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jiefei; Zhong, Yong; Wang, Liang

The design and engineering of the size, shape, and chemistry of photoactive building blocks enables the fabrication of functional nanoparticles for applications in light harvesting, photocatalytic synthesis, water splitting, phototherapy, and photodegradation. Here, we report the synthesis of such nanoparticles through a surfactant-assisted interfacial self-assembly process using optically active porphyrin as a functional building block. The self-assembly process relies on specific interactions such as π–π stacking and metalation (metal atoms and ligand coordination) between individual porphyrin building blocks. Depending on the kinetic conditions and type of surfactants, resulting structures exhibit well-defined one- to three-dimensional morphologies such as nanowires, nanooctahedra, andmore » hierarchically ordered internal architectures. Specifically, electron microscopy and X-ray diffraction results indicate that these nanoparticles exhibit stable single-crystalline and nanoporous frameworks. In conclusion, due to the hierarchical ordering of the porphyrins, the nanoparticles exhibit collective optical properties resulted from coupling of molecular porphyrins and photocatalytic activities such as photodegradation of methyl orange (MO) pollutants and hydrogen production.« less

Robust excitons inhabit soft supramolecular nanotubes

PubMed Central

Eisele, Dörthe M.; Arias, Dylan H.; Fu, Xiaofeng; Bloemsma, Erik A.; Steiner, Colby P.; Jensen, Russell A.; Rebentrost, Patrick; Eisele, Holger; Tokmakoff, Andrei; Lloyd, Seth; Nelson, Keith A.; Nicastro, Daniela; Knoester, Jasper; Bawendi, Moungi G.

2014-01-01

Nature's highly efficient light-harvesting antennae, such as those found in green sulfur bacteria, consist of supramolecular building blocks that self-assemble into a hierarchy of close-packed structures. In an effort to mimic the fundamental processes that govern nature’s efficient systems, it is important to elucidate the role of each level of hierarchy: from molecule, to supramolecular building block, to close-packed building blocks. Here, we study the impact of hierarchical structure. We present a model system that mirrors nature’s complexity: cylinders self-assembled from cyanine-dye molecules. Our work reveals that even though close-packing may alter the cylinders’ soft mesoscopic structure, robust delocalized excitons are retained: Internal order and strong excitation-transfer interactions—prerequisites for efficient energy transport—are both maintained. Our results suggest that the cylindrical geometry strongly favors robust excitons; it presents a rational design that is potentially key to nature’s high efficiency, allowing construction of efficient light-harvesting devices even from soft, supramolecular materials. PMID:25092336

Morphology-Controlled Synthesis and Metalation of Porphyrin Nanoparticles with Enhanced Photocatalytic Performance

DOE PAGES

Wang, Jiefei; Zhong, Yong; Wang, Liang; ...

2016-09-12

The design and engineering of the size, shape, and chemistry of photoactive building blocks enables the fabrication of functional nanoparticles for applications in light harvesting, photocatalytic synthesis, water splitting, phototherapy, and photodegradation. Here, we report the synthesis of such nanoparticles through a surfactant-assisted interfacial self-assembly process using optically active porphyrin as a functional building block. The self-assembly process relies on specific interactions such as π–π stacking and metalation (metal atoms and ligand coordination) between individual porphyrin building blocks. Depending on the kinetic conditions and type of surfactants, resulting structures exhibit well-defined one- to three-dimensional morphologies such as nanowires, nanooctahedra, andmore » hierarchically ordered internal architectures. Specifically, electron microscopy and X-ray diffraction results indicate that these nanoparticles exhibit stable single-crystalline and nanoporous frameworks. In conclusion, due to the hierarchical ordering of the porphyrins, the nanoparticles exhibit collective optical properties resulted from coupling of molecular porphyrins and photocatalytic activities such as photodegradation of methyl orange (MO) pollutants and hydrogen production.« less

Templated Assembly of a Functional Ordered Protein Macromolecular Framework from P22 Virus-like Particles.

PubMed

McCoy, Kimberly; Uchida, Masaki; Lee, Byeongdu; Douglas, Trevor

2018-04-24

Bottom-up construction of mesoscale materials using biologically derived nanoscale building blocks enables engineering of desired physical properties using green production methods. Virus-like particles (VLPs) are exceptional building blocks due to their monodispersed sizes, geometric shapes, production ease, proteinaceous composition, and our ability to independently functionalize the interior and exterior interfaces. Here a VLP, derived from bacteriophage P22, is used as a building block for the fabrication of a protein macromolecular framework (PMF), a tightly linked 3D network of functional protein cages that exhibit long-range order and catalytic activity. Assembly of PMFs was electrostatically templated, using amine-terminated dendrimers, then locked into place with a ditopic cementing protein that binds to P22. Long-range order is preserved on removal of the dendrimer, leaving a framework material composed completely of protein. Encapsulation of β-glucosidase enzymes inside of P22 VLPs results in formation of stable, condensed-phase materials with high local concentration of enzymes generating catalytically active PMFs.

Designed synthesis of double-stage two-dimensional covalent organic frameworks

PubMed Central

Chen, Xiong; Addicoat, Matthew; Jin, Enquan; Xu, Hong; Hayashi, Taku; Xu, Fei; Huang, Ning; Irle, Stephan; Jiang, Donglin

2015-01-01

Covalent organic frameworks (COFs) are an emerging class of crystalline porous polymers in which organic building blocks are covalently and topologically linked to form extended crystalline polygon structures, constituting a new platform for designing π-electronic porous materials. However, COFs are currently synthesised by a few chemical reactions, limiting the access to and exploration of new structures and properties. The development of new reaction systems that avoid such limitations to expand structural diversity is highly desired. Here we report that COFs can be synthesised via a double-stage connection that polymerises various different building blocks into crystalline polygon architectures, leading to the development of a new type of COFs with enhanced structural complexity and diversity. We show that the double-stage approach not only controls the sequence of building blocks but also allows fine engineering of pore size and shape. This strategy is widely applicable to different polymerisation systems to yield hexagonal, tetragonal and rhombus COFs with predesigned pores and π-arrays. PMID:26456081

Engineering cell factories for producing building block chemicals for bio-polymer synthesis.

PubMed

Tsuge, Yota; Kawaguchi, Hideo; Sasaki, Kengo; Kondo, Akihiko

2016-01-21

Synthetic polymers are widely used in daily life. Due to increasing environmental concerns related to global warming and the depletion of oil reserves, the development of microbial-based fermentation processes for the production of polymer building block chemicals from renewable resources is desirable to replace current petroleum-based methods. To this end, strains that efficiently produce the target chemicals at high yields and productivity are needed. Recent advances in metabolic engineering have enabled the biosynthesis of polymer compounds at high yield and productivities by governing the carbon flux towards the target chemicals. Using these methods, microbial strains have been engineered to produce monomer chemicals for replacing traditional petroleum-derived aliphatic polymers. These developments also raise the possibility of microbial production of aromatic chemicals for synthesizing high-performance polymers with desirable properties, such as ultraviolet absorbance, high thermal resistance, and mechanical strength. In the present review, we summarize recent progress in metabolic engineering approaches to optimize microbial strains for producing building blocks to synthesize aliphatic and high-performance aromatic polymers.

Recurrence of 49-base decamers, nonomers, and octamers within mouse C mu gene of Ig heavy chain and its primordial building block.

PubMed Central

Yazaki, A; Ohno, S

1983-01-01

Within the published 2,168-base-long mouse C mu gene of Ig heavy chain consisting of four coding and four noncoding segments, 2 base decamers, 8 nonomers, and 39 octamers recurred. Recurring base heptamers (about 100) and hexamers (about 350) were simply too numerous to merit individual identification. In spite of extensive overlaps between these recurring base decamers to hexamers, they occupied nearly the entire length of mouse Ig C mu gene. As with other genes of the beta-sheet-forming beta 2-microglobulin family, the Ig C mu gene (flanking and intervening noncoding sequences included) is not a unique sequence but rather it is degenerate repeats of the 45-base-long primordial building-block sequence uniquely its own. This primordial building block must originally have specified the 15-amino-acid-residue-long primordial arm of beta-sheet-forming loops, the characteristics of the beta 2-microglobulin family of polypeptides. PMID:6403948

Exploring the building blocks of social cognition: spontaneous agency perception and visual perspective taking in autism.

PubMed

Zwickel, Jan; White, Sarah J; Coniston, Devorah; Senju, Atsushi; Frith, Uta

2011-10-01

Individuals with autism spectrum disorders have highly characteristic impairments in social interaction and this is true also for those with high functioning autism or Asperger syndrome (AS). These social cognitive impairments are far from global and it seems likely that some of the building blocks of social cognition are intact. In our first experiment, we investigated whether high functioning adults who also had a diagnosis of AS would be similar to control participants in terms of their eye movements when watching animated triangles in short movies that normally evoke mentalizing. They were. Our second experiment using the same movies, tested whether both groups would spontaneously adopt the visuo-spatial perspective of a triangle protagonist. They did. At the same time autistic participants differed in their verbal accounts of the story line underlying the movies, confirming their specific difficulties in on-line mentalizing. In spite of this difficulty, two basic building blocks of social cognition appear to be intact: spontaneous agency perception and spontaneous visual perspective taking.

Appendices for the Space Applications program, 1974

NASA Technical Reports Server (NTRS)

1974-01-01

To achieve truly low cost system design with direct evolution for inorbit shuttle resupply, a modular building block approach has been adopted. The heart of the modular building block concept lies in the ability to use a common set of nonoptimized subsystems in such a way that a wide variety of missions can be flown with no detrimental impact on performance. By standardizing the mechanical configurations and electrical interfaces of the subsystem modules, and by designing each of them to be structurally and thermally independent entities, it is possible to cluster these building blocks or modules about an instrument system so as to adequately perform the mission without the need for subsystem redevelopments for each mission. This system concept offers the following capabilities: (1) the ability to launch and orbit the observatory by either the Delta, the Titan, or the space shuttle. (2) the ability to completely reconfigure the spacecraft subsystems for different launch vehicles, and (3) the ability to perform in-orbit resupply and/or emergency retrieval of the observatory.

Elasticity-dependent fast underwater adhesion demonstrated by macroscopic supramolecular assembly.

PubMed

Ju, Guannan; Cheng, Mengjiao; Guo, Fengli; Zhang, Qian; Shi, Feng

2018-05-30

Macroscopic supramolecular assembly (MSA) is a recent progress in supramolecular chemistry to associate visible building blocks through non-covalent interactions in a multivalent manner. Although various substrates (e. g. hydrogels, rigid materials) have been used, a general design rule of building blocks in MSA systems and interpretation of the assembly mechanism are still lacking and urgently in demand. Here we design three model systems with varied modulus and correlated the MSA probability with the elasticity. Based on the effects of substrate deformability on multivalency, we have proposed an elastic-modulus-dependent rule that building blocks below a critical modulus of 2.5 MPa can achieve MSA for the used host/guest system. Moreover, this MSA rule applies well to the design of materials applicable for fast underwater adhesion: Soft substrates (0.5 MPa) can achieve underwater adhesion within 10 s with one magnitude higher strength than that of rigid substrates (2.5 MPa). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

High-flexibility combinatorial peptide synthesis with laser-based transfer of monomers in solid matrix material.

PubMed

Loeffler, Felix F; Foertsch, Tobias C; Popov, Roman; Mattes, Daniela S; Schlageter, Martin; Sedlmayr, Martyna; Ridder, Barbara; Dang, Florian-Xuan; von Bojničić-Kninski, Clemens; Weber, Laura K; Fischer, Andrea; Greifenstein, Juliane; Bykovskaya, Valentina; Buliev, Ivan; Bischoff, F Ralf; Hahn, Lothar; Meier, Michael A R; Bräse, Stefan; Powell, Annie K; Balaban, Teodor Silviu; Breitling, Frank; Nesterov-Mueller, Alexander

2016-06-14

Laser writing is used to structure surfaces in many different ways in materials and life sciences. However, combinatorial patterning applications are still limited. Here we present a method for cost-efficient combinatorial synthesis of very-high-density peptide arrays with natural and synthetic monomers. A laser automatically transfers nanometre-thin solid material spots from different donor slides to an acceptor. Each donor bears a thin polymer film, embedding one type of monomer. Coupling occurs in a separate heating step, where the matrix becomes viscous and building blocks diffuse and couple to the acceptor surface. Furthermore, we can consecutively deposit two material layers of activation reagents and amino acids. Subsequent heat-induced mixing facilitates an in situ activation and coupling of the monomers. This allows us to incorporate building blocks with click chemistry compatibility or a large variety of commercially available non-activated, for example, posttranslationally modified building blocks into the array's peptides with >17,000 spots per cm(2).

Designed synthesis of double-stage two-dimensional covalent organic frameworks

NASA Astrophysics Data System (ADS)

Chen, Xiong; Addicoat, Matthew; Jin, Enquan; Xu, Hong; Hayashi, Taku; Xu, Fei; Huang, Ning; Irle, Stephan; Jiang, Donglin

2015-10-01

Covalent organic frameworks (COFs) are an emerging class of crystalline porous polymers in which organic building blocks are covalently and topologically linked to form extended crystalline polygon structures, constituting a new platform for designing π-electronic porous materials. However, COFs are currently synthesised by a few chemical reactions, limiting the access to and exploration of new structures and properties. The development of new reaction systems that avoid such limitations to expand structural diversity is highly desired. Here we report that COFs can be synthesised via a double-stage connection that polymerises various different building blocks into crystalline polygon architectures, leading to the development of a new type of COFs with enhanced structural complexity and diversity. We show that the double-stage approach not only controls the sequence of building blocks but also allows fine engineering of pore size and shape. This strategy is widely applicable to different polymerisation systems to yield hexagonal, tetragonal and rhombus COFs with predesigned pores and π-arrays.

[Ropivacaine use in transnasal sphenopalatine ganglion block for post dural puncture headache in obstetric patients - case series].

PubMed

Furtado, Inês; Lima, Isabel Flor de; Pedro, Sérgio

2018-02-02

Sphenopalatine ganglion block is widely accepted in chronic pain; however it has been underestimated in post dural puncture headache treatment. The ganglion block does not restore normal cerebrospinal fluid dynamics but effectively reduces symptoms associated with resultant hypotension. When correctly applied it may avoid performance of epidural blood patch. The transnasal approach is a simple and minimally invasive technique. In the cases presented, we attempted to perform and report the ganglion block effectiveness and duration, using ropivacaine. We present four obstetrics patients with post dural puncture headache, after epidural or combined techniques, with Tuohy needle 18G that underwent a safe and successful Sphenopalatine ganglion block. We performed the block 24-48h after dural puncture, with 4mL of ropivacaine 0.75% in each nostril. In three cases pain recurred within 12-48h, although less intense. In one patient a second block was performed with complete relief and without further recurrence. In the other two patients a blood patch was performed without success. All patients were asymptomatic within 7 days. The average duration of analgesic effect of the block remains poorly defined. In the cases reported, blocking with ropivacaine was a simple, safe and effective technique, with immediate and sustained pain relief for at least 12-24h. Copyright © 2017 Sociedade Brasileira de Anestesiologia. Publicado por Elsevier Editora Ltda. All rights reserved.

Synthetic analog computation in living cells.

PubMed

Daniel, Ramiz; Rubens, Jacob R; Sarpeshkar, Rahul; Lu, Timothy K

2013-05-30

A central goal of synthetic biology is to achieve multi-signal integration and processing in living cells for diagnostic, therapeutic and biotechnology applications. Digital logic has been used to build small-scale circuits, but other frameworks may be needed for efficient computation in the resource-limited environments of cells. Here we demonstrate that synthetic analog gene circuits can be engineered to execute sophisticated computational functions in living cells using just three transcription factors. Such synthetic analog gene circuits exploit feedback to implement logarithmically linear sensing, addition, ratiometric and power-law computations. The circuits exhibit Weber's law behaviour as in natural biological systems, operate over a wide dynamic range of up to four orders of magnitude and can be designed to have tunable transfer functions. Our circuits can be composed to implement higher-order functions that are well described by both intricate biochemical models and simple mathematical functions. By exploiting analog building-block functions that are already naturally present in cells, this approach efficiently implements arithmetic operations and complex functions in the logarithmic domain. Such circuits may lead to new applications for synthetic biology and biotechnology that require complex computations with limited parts, need wide-dynamic-range biosensing or would benefit from the fine control of gene expression.

Modulation and multiplexing in ultra-broadband photonic internet: Part II

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2011-06-01

In this paper, there is presented a review of our today's understanding of the ultimately broadband photonic Internet. A simple calculation is presented showing the estimate of the throughput of the core photonic network branches. Optoelectronic components, circuits, systems and signals, together with analogous electronic entities and common software layers, are building blocks of the contemporary Internet. Participation of photonics in development of the physical layer in the future Internet will probably increase. The photonics leads now to a better usage of the available bandwidth (increase of the spectral efficiency measured in Bit/s/Hz), increase in the transmission rate (from Gbps, via Tbps up to probably Pbps), increase in the transmission distance without signal regeneration (in distortion compensated active optical cables), increase in energy/power efficiency measured in W/Gbps, etc. Photonics may lead, in the future, to fully transparent optical networks and, thus, to essential increase in bandwidth and network reliability. It is expected that photonics (with biochemistry, electronics and mechatronics) may build psychological and physiological interface for humans to the future global network. The following optical signal multiplexing methods were considered, which are possible without O/E/O conversion: TDM-OTDM, FDM-CO-OFDM, OCDM-OCDMA, WDM-DWDM.

Ultra-broadband photonic internet

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2011-06-01

In this paper, there is presented a review of our today's understanding of the ultimately broadband photonic Internet. A simple calculation is presented showing the estimate of the throughput of the core photonic network branches. Optoelectronic components, circuits, systems and signals, together with analogous electronic entities and common software layers, are building blocks of the contemporary Internet. Participation of photonics in development of the physical layer in the future Internet will probably increase. The photonics leads now to a better usage of the available bandwidth (increase of the spectral efficiency measured in Bit/s/Hz), increase in the transmission rate (from Gbps, via Tbps up to probably Pbps), increase in the transmission distance without signal regeneration (in distortion compensated active optical cables), increase in energy/power efficiency measured in W/Gbps, etc. Photonics may lead, in the future, to fully transparent optical networks and, thus, to essential increase in bandwidth and network reliability. It is expected that photonics (with biochemistry, electronics and mechatronics) may build psychological and physiological interface for humans to the future global network. The following optical signal multiplexing methods were considered, which are possible without O/E/O conversion: TDM-OTDM, FDM-CO-OFDM, OCDM-OCDMA, WDM-DWDM.

Modulation and multiplexing in ultra-broadband photonic internet: Part I

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2011-06-01

In this paper, there is presented a review of our today's understanding of the ultimately broadband photonic Internet. A simple calculation is presented showing the estimate of the throughput of the core photonic network branches. Optoelectronic components, circuits, systems and signals, together with analogous electronic entities and common software layers, are building blocks of the contemporary Internet. Participation of photonics in development of the physical layer in the future Internet will probably increase. The photonics leads now to a better usage of the available bandwidth (increase of the spectral efficiency measured in Bit/s/Hz), increase in the transmission rate (from Gbps, via Tbps up to probably Pbps), increase in the transmission distance without signal regeneration (in distortion compensated active optical cables), increase in energy/power efficiency measured in W/Gbps, etc. Photonics may lead, in the future, to fully transparent optical networks and, thus, to essential increase in bandwidth and network reliability. It is expected that photonics (with biochemistry, electronics and mechatronics) may build psychological and physiological interface for humans to the future global network. The following optical signal multiplexing methods were considered, which are possible without O/E/O conversion: TDM-OTDM, FDM-CO-OFDM, OCDM-OCDMA, WDM-DWDM.

A molecular quantum spin network controlled by a single qubit.

PubMed

Schlipf, Lukas; Oeckinghaus, Thomas; Xu, Kebiao; Dasari, Durga Bhaktavatsala Rao; Zappe, Andrea; de Oliveira, Felipe Fávaro; Kern, Bastian; Azarkh, Mykhailo; Drescher, Malte; Ternes, Markus; Kern, Klaus; Wrachtrup, Jörg; Finkler, Amit

2017-08-01

Scalable quantum technologies require an unprecedented combination of precision and complexity for designing stable structures of well-controllable quantum systems on the nanoscale. It is a challenging task to find a suitable elementary building block, of which a quantum network can be comprised in a scalable way. We present the working principle of such a basic unit, engineered using molecular chemistry, whose collective control and readout are executed using a nitrogen vacancy (NV) center in diamond. The basic unit we investigate is a synthetic polyproline with electron spins localized on attached molecular side groups separated by a few nanometers. We demonstrate the collective readout and coherent manipulation of very few (≤ 6) of these S = 1/2 electronic spin systems and access their direct dipolar coupling tensor. Our results show that it is feasible to use spin-labeled peptides as a resource for a molecular qubit-based network, while at the same time providing simple optical readout of single quantum states through NV magnetometry. This work lays the foundation for building arbitrary quantum networks using well-established chemistry methods, which has many applications ranging from mapping distances in single molecules to quantum information processing.

[The clinical study on labor pain relief using two kinds of segmental block anesthesia].

PubMed

Zhang, Z; Zhang, Y; Bi, L

1998-07-01

To study the pain relief effectiveness of combined subarachnoid peridural segmental block and simple peridural anesthesia, and their influences on the mothers and the infants. 100 pregnants women were administered combined subarachnoid and peridural segmental block during labor and delivery (study group). 40 pregnant women received simple peridural anesthesia (control group). The degree of labour pain, side effects, labor course, the mode of delivery and the incidences of postpartum hemorrhage, fetal distress and neonatal asphyxia were observed in two groups respectively. The pain relief effect in the study group was much better than that of the control group (P < 0.01). There were no significant differences of the mean time of labor course and the mode of delivery between the two groups (P > 0.05). The incidences of postpartum hemorrhage, fetal distress and neonatal asphyxia were similar (P > 0.05). The analgesic delivery of combined subarachnoid and peridural segmental block is safe and effective, which has no influences on the labour course and the mothers and infants. Its pain relief effectiveness is more positive and satisfactory than that of simple peridural anesthesia. We suggest that it should be performed in the medical units under optimal conditions.

Correlating the magic numbers of inorganic nanomolecular assemblies with a {Pd84} molecular-ring Rosetta Stone

PubMed Central

Xu, Feng; Miras, Haralampos N.; Scullion, Rachel A.; Long, De-Liang; Thiel, Johannes; Cronin, Leroy

2012-01-01

Molecular self-assembly has often been suggested as the ultimate route for the bottom-up construction of building blocks atom-by-atom for functional nanotechnology, yet structural design or prediction of nanomolecular assemblies is still far from reach. Whereas nature uses complex machinery such as the ribosome, chemists use painstakingly engineered step-by-step approaches to build complex molecules but the size and complexity of such molecules, not to mention the accessible yields, can be limited. Herein we present the discovery of a palladium oxometalate {Pd84}-ring cluster 3.3 nm in diameter; [Pd84O42(OAc)28(PO4)42]70- ({Pd84} ≡ {Pd12}7) that is formed in water just by mixing two reagents at room temperature, giving crystals of the compound in just a few days. The structure of the {Pd84}-ring has sevenfold symmetry, comprises 196 building blocks, and we also show, using mass spectrometry, that a large library of other related nanostructures is present in solution. Finally, by analysis of the symmetry and the building block library that construct the {Pd84} we show that the correlation of the symmetry, subunit number, and overall cluster nuclearity can be used as a “Rosetta Stone” to rationalize the “magic numbers” defining a number of other systems. This is because the discovery of {Pd84} allows the relationship between seemingly unrelated families of molecular inorganic nanosystems to be decoded from the overall cluster magic-number nuclearity, to the symmetry and building blocks that define such structures allowing the prediction of other members of these nanocluster families. PMID:22753516

Hydrophilic interaction chromatography-multiple reaction monitoring mass spectrometry method for basic building block analysis of low molecular weight heparins prepared through nitrous acid depolymerization.

PubMed

Sun, Xiaojun; Guo, Zhimou; Yu, Mengqi; Lin, Chao; Sheng, Anran; Wang, Zhiyu; Linhardt, Robert J; Chi, Lianli

2017-01-06

Low molecular weight heparins (LMWHs) are important anticoagulant drugs that are prepared through depolymerization of unfractionated heparin. Based on the types of processing reactions and the structures of the products, LMWHs can be divided into different classifications. Enoxaparin is prepared by benzyl esterification and alkaline depolymerization, while dalteparin and nadroparin are prepared through nitrous acid depolymerization followed by borohydride reduction. Compositional analysis of their basic building blocks is an effective way to provide structural information on heparin and LMWHs. However, most current compositional analysis methods have been limited to heparin and enoxaparin. A sensitive and comprehensive approach is needed for detailed investigation of the structure of LMWHs prepared through nitrous acid depolymerization, especially their characteristic saturated non-reducing end (NRE) and 2,5-anhydro-d-mannitol reducing end (RE). A maltose modified hydrophilic interaction column offers improved separation of complicated mixtures of acidic disaccharides and oligosaccharides. A total of 36 basic building blocks were unambiguously identified by high-resolution tandem mass spectrometry (MS). Multiple reaction monitoring (MRM) MS/MS quantification was developed and validated in the analysis of dalteparin and nadroparin samples. Each group of building blocks revealed different aspects of the properties of LMWHs, such as functional motifs required for anticoagulant activity, the structure of heparin starting materials, cleavage sites in the depolymerization reaction, and undesired structural modifications resulting from side reactions. Copyright © 2016 Elsevier B.V. All rights reserved.

Layer-by-layer assembly of two-dimensional materials into wafer-scale heterostructures

NASA Astrophysics Data System (ADS)

Kang, Kibum; Lee, Kan-Heng; Han, Yimo; Gao, Hui; Xie, Saien; Muller, David A.; Park, Jiwoong

2017-10-01

High-performance semiconductor films with vertical compositions that are designed to atomic-scale precision provide the foundation for modern integrated circuitry and novel materials discovery. One approach to realizing such films is sequential layer-by-layer assembly, whereby atomically thin two-dimensional building blocks are vertically stacked, and held together by van der Waals interactions. With this approach, graphene and transition-metal dichalcogenides--which represent one- and three-atom-thick two-dimensional building blocks, respectively--have been used to realize previously inaccessible heterostructures with interesting physical properties. However, no large-scale assembly method exists at present that maintains the intrinsic properties of these two-dimensional building blocks while producing pristine interlayer interfaces, thus limiting the layer-by-layer assembly method to small-scale proof-of-concept demonstrations. Here we report the generation of wafer-scale semiconductor films with a very high level of spatial uniformity and pristine interfaces. The vertical composition and properties of these films are designed at the atomic scale using layer-by-layer assembly of two-dimensional building blocks under vacuum. We fabricate several large-scale, high-quality heterostructure films and devices, including superlattice films with vertical compositions designed layer-by-layer, batch-fabricated tunnel device arrays with resistances that can be tuned over four orders of magnitude, band-engineered heterostructure tunnel diodes, and millimetre-scale ultrathin membranes and windows. The stacked films are detachable, suspendable and compatible with water or plastic surfaces, which will enable their integration with advanced optical and mechanical systems.

Layer-by-layer assembly of two-dimensional materials into wafer-scale heterostructures.

PubMed

Kang, Kibum; Lee, Kan-Heng; Han, Yimo; Gao, Hui; Xie, Saien; Muller, David A; Park, Jiwoong

2017-10-12

High-performance semiconductor films with vertical compositions that are designed to atomic-scale precision provide the foundation for modern integrated circuitry and novel materials discovery. One approach to realizing such films is sequential layer-by-layer assembly, whereby atomically thin two-dimensional building blocks are vertically stacked, and held together by van der Waals interactions. With this approach, graphene and transition-metal dichalcogenides-which represent one- and three-atom-thick two-dimensional building blocks, respectively-have been used to realize previously inaccessible heterostructures with interesting physical properties. However, no large-scale assembly method exists at present that maintains the intrinsic properties of these two-dimensional building blocks while producing pristine interlayer interfaces, thus limiting the layer-by-layer assembly method to small-scale proof-of-concept demonstrations. Here we report the generation of wafer-scale semiconductor films with a very high level of spatial uniformity and pristine interfaces. The vertical composition and properties of these films are designed at the atomic scale using layer-by-layer assembly of two-dimensional building blocks under vacuum. We fabricate several large-scale, high-quality heterostructure films and devices, including superlattice films with vertical compositions designed layer-by-layer, batch-fabricated tunnel device arrays with resistances that can be tuned over four orders of magnitude, band-engineered heterostructure tunnel diodes, and millimetre-scale ultrathin membranes and windows. The stacked films are detachable, suspendable and compatible with water or plastic surfaces, which will enable their integration with advanced optical and mechanical systems.

To Know, or Not to Know - Why it is Important to Understand Both What we Know, and What We Don't Know, When Studying Our Air and Sky

NASA Astrophysics Data System (ADS)

Brown-Steiner, B.

2017-12-01

I study the air and the sky, which can get really, really confusing. When you cup your hands and catch some air, you are holding many hundreds of hundreds of hundreds (do this about ten more times) of really tiny building blocks that keep hitting (and changing) one another every second of every day. We need some of these tiny building blocks to live and breathe, but there are many tiny building blocks that can hurt us - or even kill us. Right now, the way we live - how we make power, how we make food, how we get from place to place - adds a lot of bad building blocks to our air and our sky, and is changing our world in ways we do not really understand. As we learn more about the air and the sky, we get better at knowing how things are changing, but it is also really important to think about the things we do not know, and the things we do not understand. I study our air and our sky by thinking hard not only about the things that we know, but also about the things we do not know, and I try to use what I learn to help us make more sense out of the really confusing stuff. I want to share some of what I have learned with you.

Mononuclear, trinuclear, and hetero-trinuclear supramolecular complexes containing a new tri-sulfonate ligand and cobalt(II)/copper(II)-(1,10-phenanthroline) 2 building blocks

NASA Astrophysics Data System (ADS)

Yu, Yunfang; Wei, Yongqin; Broer, Ria; Sa, Rongjian; Wu, Kechen

2008-03-01

Novel mononuclear, trinuclear, and hetero-trinuclear supermolecular complexes, [Co(phen) 2(H 2O)(HTST)]·2H 2O ( 1), [Co 3(phen) 6(H 2O) 2(TST) 2]·7H 2O ( 2), and [Co 2Cu(phen) 6(H 2O) 2(TST) 2]·10H 2O ( 3), have been synthesized by the reactions of a new tri-sulfonate ligand (2,4,6-tris(4-sulfophenylamino)-1,3,5-triazine, H 3TST) with the M2+ ( M=Co, Cu) and the second ligand 1,10-phenanthroline (phen). Complex 1 contains a cis-Co(II)(phen) 2 building block and an HTST as monodentate ligand; complex 2 consists of two TST as bidentate ligands connecting one trans- and two cis-Co(II)(phen) 2 building blocks; complex 3 is formed by replacing the trans-Co(II)(phen) 2 in 2 with a trans-Cu(II)(phen) 2, which is the first reported hetero-trinuclear supramolecular complex containing both the Co(II)(phen) 2 and Cu(II)(phen) 2 as building blocks. The study shows the flexible multifunctional self-assembly capability of the H 3TST ligands presenting in these supramolecular complexes through coordinative, H-bonding and even π- π stacking interactions. The photoluminescent optical properties of these complexes are also investigated and discussed as well as the second-order nonlinear optical properties of 1.

The Building Blocks for JWST I and T (Integrations and Test) to Operations - From Simulator to Flight Units

NASA Technical Reports Server (NTRS)

Fatig, Curtis; Ochs, William; Johns, Alan; Seaton, Bonita; Adams, Cynthia; Wasiak, Francis; Jones, Ronald; Jackson, Wallace

2012-01-01

The James Webb Space Telescope (JWST) Project has an extended integration and test (I&T) phase due to long procurement and development times of various components as well as recent launch delays. The JWST Ground Segment and Operations group has developed a roadmap of the various ground and flight elements and their use in the various JWST I&T test programs. The JWST Project s building block approach to the eventual operational systems, while not new, is complex and challenging; a large-scale mission like JWST involves international partners, many vendors across the United States, and competing needs for the same systems. One of the challenges is resource balancing so simulators and flight products for various elements congeal into integrated systems used for I&T and flight operations activities. This building block approach to an incremental buildup provides for early problem identification with simulators and exercises the flight operations systems, products, and interfaces during the JWST I&T test programs. The JWST Project has completed some early I&T with the simulators, engineering models and some components of the operational ground system. The JWST Project is testing the various flight units as they are delivered and will continue to do so for the entire flight and operational system. The JWST Project has already and will continue to reap the value of the building block approach on the road to launch and flight operations.

Refined Synthesis of 2,3,4,5-Tetrahydro-1,3,3-trimethyldipyrrin, a Deceptively Simple Precursor to Hydroporphyrins

PubMed Central

Ptaszek, Marcin; Bhaumik, Jayeeta; Kim, Han-Je; Taniguchi, Masahiko; Lindsey, Jonathan S.

2008-01-01

2,3,4,5-Tetrahydro-1,3,3-trimethyldipyrrin (1) is a crucial building block in the rational synthesis of chlorins and oxochlorins. The prior 5-step synthesis of 1 from pyrrole-2-carboxaldehyde (2) employed relatively simple and well-known reactions yet suffered from several drawbacks, including limited scale (≥ 0.5 g of 1 per run). A streamlined preparation of 1 has been developed that entails four steps: (i) nitro-aldol condensation of 2 and nitromethane under neat conditions to give 2-(2-nitrovinyl)pyrrole (3), (ii) reduction of 3 with NaBH4 to give 2-(2-nitroethyl)pyrrole (4), (iii) Michael addition of 4 with mesityl oxide under neat conditions or at high concentration to give γ-nitrohexanonepyrrole 5, and (iv) reductive cyclization of 5 with zinc/ammonium formate to give 1. Several multistep transformations have been established, including the direct conversion of 2 → 1. The advantages of the new procedures include (1) fewer steps, (2) avoidance of several problematic reagents, (3) diminished consumption of solvents and reagents, (4) lessened reliance on chromatography, and (5) scalability. The new procedures facilitate the preparation of 1 at the multigram scale. PMID:19132135

How do bendy straws bend? A study of re-configurability of multi-stable corrugated shells

NASA Astrophysics Data System (ADS)

Bende, Nakul; Selden, Sarah; Evans, Arthur; Santangelo, Christian; Hayward, Ryan

Shape programmable systems have evolved to allow for reconfiguration of structures through a variety of mechanisms including swelling, stress-relaxation, and thermal expansion. Particularly, there has been a recent interest in systems that exhibit bi-stability or multi-stability to achieve transformation between two or more pre-programmed states. Here, we study the ubiquitous architecture of corrugated shells, such as drinking straws or bellows, which has been well known for centuries. Some of these structures exhibit almost continuous stability amongst a wide range of reconfigurable shapes, but the underlying mechanisms are not well understood. To understand multi-stability in `bendy-straw' structures, we study the unit bi-conical segment using experiments and finite element modeling to elucidate the key geometrical and mechanical factors responsible for its multi-stability. The simple transformations of a unit segment - a change in length or angle can impart complex re-configurability of a structure containing many of these units. The fundamental understanding provided of this simple multi-stable building block could yield improvements in shape re-configurability for a wide array of applications such as corrugated medical tubing, robotics, and deployable structures. NSF EFRI ODISSEI-1240441.

Simple and Efficient Single Photon Filter for a Rb-based Quantum Memory

NASA Astrophysics Data System (ADS)

Stack, Daniel; Li, Xiao; Quraishi, Qudsia

2015-05-01

Distribution of entangled quantum states over significant distances is important to the development of future quantum technologies such as long-distance cryptography, networks of atomic clocks, distributed quantum computing, etc. Long-lived quantum memories and single photons are building blocks for systems capable of realizing such applications. The ability to store and retrieve quantum information while filtering unwanted light signals is critical to the operation of quantum memories based on neutral-atom ensembles. We report on an efficient frequency filter which uses a glass cell filled with 85Rb vapor to attenuate noise photons by an order of magnitude with little loss to the single photons associated with the operation of our cold 87Rb quantum memory. An Ar buffer gas is required to differentiate between signal and noise photons or similar statement. Our simple, passive filter requires no optical pumping or external frequency references and provides an additional 18 dB attenuation of our pump laser for every 1 dB loss of the single photon signal. We observe improved non-classical correlations and our data shows that the addition of a frequency filter increases the non-classical correlations and readout efficiency of our quantum memory by ~ 35%.