Using the Cambridge Structural Database to Teach Molecular Geometry Concepts in Organic Chemistry

ERIC Educational Resources Information Center

Wackerly, Jay Wm.; Janowicz, Philip A.; Ritchey, Joshua A.; Caruso, Mary M.; Elliott, Erin L.; Moore, Jeffrey S.

2009-01-01

This article reports a set of two homework assignments that can be used in a second-year undergraduate organic chemistry class. These assignments were designed to help reinforce concepts of molecular geometry and to give students the opportunity to use a technological database and data mining to analyze experimentally determined chemical…

Binary polymorphic cocrystals: an update on the available literature in the Cambridge Structural Database, including a new polymorph of the pharmaceutical 1:1 cocrystal theophylline-3,4-dihydroxybenzoic acid.

PubMed

Mnguni, Malitsatsi J; Michael, Joseph P; Lemmerer, Andreas

2018-06-01

An analysis and classification of the 2925 neutral binary organic cocrystals in the Cambridge Structural Database is reported, focusing specifically on those both showing polymorphism and containing an active pharmaceutical ingredient (API). The search was confined to molecules having only C, H, N, O, S and halogens atoms. It was found that 400 out of 2925 cocrystals can be classified as pharmaceutical cocrystals, containing at least one API, and that of those, 56 can be classified as being polymorphic cocrystals. In general, the total number of polymorphic cocrystal systems of any type stands at 125. In addition, a new polymorph of the pharmaceutical cocrystal theophylline-3,4-dihydroxybenzoic acid (1/1), C 7 H 8 N 4 O 2 ·C 7 H 6 O 4 , is reported.

Stacking interactions of hydrogen-bridged rings – stronger than the stacking of benzene molecules.

PubMed

Blagojević, Jelena P; Zarić, Snežana D

2015-08-21

Analysis of crystal structures from the Cambridge Structural Database showed that 27% of all planar five-membered hydrogen-bridged rings, possessing only single bonds within the ring, form intermolecular stacking interactions. Interaction energy calculations show that interactions can be as strong as -4.9 kcal mol(-1), but dependent on ring structure.

Data to knowledge: how to get meaning from your result.

PubMed

Berman, Helen M; Gabanyi, Margaret J; Groom, Colin R; Johnson, John E; Murshudov, Garib N; Nicholls, Robert A; Reddy, Vijay; Schwede, Torsten; Zimmerman, Matthew D; Westbrook, John; Minor, Wladek

2015-01-01

Structural and functional studies require the development of sophisticated 'Big Data' technologies and software to increase the knowledge derived and ensure reproducibility of the data. This paper presents summaries of the Structural Biology Knowledge Base, the VIPERdb Virus Structure Database, evaluation of homology modeling by the Protein Model Portal, the ProSMART tool for conformation-independent structure comparison, the LabDB 'super' laboratory information management system and the Cambridge Structural Database. These techniques and technologies represent important tools for the transformation of crystallographic data into knowledge and information, in an effort to address the problem of non-reproducibility of experimental results.

Hydrogen-bond landscapes, geometry and energetics of squaric acid and its mono- and dianions: a Cambridge Structural Database, IsoStar and computational study.

PubMed

Allen, Frank H; Cruz-Cabeza, Aurora J; Wood, Peter A; Bardwell, David A

2013-10-01

As part of a programme of work to extend central-group coverage in the Cambridge Crystallographic Data Centre's (CCDC) IsoStar knowledge base of intermolecular interactions, we have studied the hydrogen-bonding abilities of squaric acid (H2SQ) and its mono- and dianions (HSQ(-) and SQ(2-)) using the Cambridge Structural Database (CSD) along with dispersion-corrected density functional theory (DFT-D) calculations for a range of hydrogen-bonded dimers. The -OH and -C=O groups of H2SQ, HSQ(-) and SQ(2-) are potent donors and acceptors, as indicated by their hydrogen-bond geometries in available crystal structures in the CSD, and by the attractive energies calculated for their dimers with acetone and methanol, which were used as model acceptors and donors. The two anions have sufficient examples in the CSD for their addition as new central groups in IsoStar. It is also shown that charge- and resonance-assisted hydrogen bonds involving H2SQ and HSQ(-) are similar in strength to those made by carboxylate COO(-) acceptors, while hydrogen bonds made by the dianion SQ(2-) are somewhat stronger. The study reinforces the value of squaric acid and its anions as cocrystal formers and their actual and potential importance as isosteric replacements for carboxylic acid and carboxylate functions.

Learning about Intermolecular Interactions from the Cambridge Structural Database

ERIC Educational Resources Information Center

Battle, Gary M.; Allen, Frank H.

2012-01-01

A clear understanding and appreciation of noncovalent interactions, especially hydrogen bonding, are vitally important to students of chemistry and the life sciences, including biochemistry, molecular biology, pharmacology, and medicine. The opportunities afforded by the IsoStar knowledge base of intermolecular interactions to enhance the…

Data to knowledge: how to get meaning from your result

PubMed Central

Berman, Helen M.; Gabanyi, Margaret J.; Groom, Colin R.; Johnson, John E.; Murshudov, Garib N.; Nicholls, Robert A.; Reddy, Vijay; Schwede, Torsten; Zimmerman, Matthew D.; Westbrook, John; Minor, Wladek

2015-01-01

Structural and functional studies require the development of sophisticated ‘Big Data’ technologies and software to increase the knowledge derived and ensure reproducibility of the data. This paper presents summaries of the Structural Biology Knowledge Base, the VIPERdb Virus Structure Database, evaluation of homology modeling by the Protein Model Portal, the ProSMART tool for conformation-independent structure comparison, the LabDB ‘super’ laboratory information management system and the Cambridge Structural Database. These techniques and technologies represent important tools for the transformation of crystallographic data into knowledge and information, in an effort to address the problem of non-reproducibility of experimental results. PMID:25610627

Structural investigation of the β-cyclodextrin complexes with chiral bicyclic monoterpenes - Influence of the functionality group on the host-guest stoichiometry

NASA Astrophysics Data System (ADS)

Ceborska, Magdalena

2017-10-01

The crystal structures of the complexes of β-cyclodextrin with (+)- and (-)-camphors are presented. The comparison of the obtained crystal structures with available data for other complexes of β-cyclodextrin with chiral bicyclic monoterpenes (hydrocarbon (+)-fenchene and alcohols: (-)-isopinocampheol, and (+)-, and (-)-borneols) obtained from Cambridge Structural Database (CSD) shows the trend of alcohols to form dimeric complexes of 2:3 stoichiometry, while hydrocarbons and ketones prefer to form 2:2 host-guest inclusion complexes.

Using more than 801 296 small-molecule crystal structures to aid in protein structure refinement and analysis

PubMed Central

Cole, Jason C.

2017-01-01

The Cambridge Structural Database (CSD) is the worldwide resource for the dissemination of all published three-dimensional structures of small-molecule organic and metal–organic compounds. This paper briefly describes how this collection of crystal structures can be used en masse in the context of macromolecular crystallography. Examples highlight how the CSD and associated software aid protein–ligand complex validation, and show how the CSD could be further used in the generation of geometrical restraints for protein structure refinement. PMID:28291758

Quantum mechanics models of the methanol dimer: O-H…O hydrogen bonds of ß-D-glucose moieties from crystallographic data.

USDA-ARS?s Scientific Manuscript database

In this study, a survey of the Cambridge Crystal Structure Database for all donor-acceptor interactions in ß-D-glucose moieties was performed to examine the similarities and differences among the different hydroxyl groups and ether oxygen atoms that participate in hydrogen bonds. Comparable behavior...

Characteristic conformation of Mosher's amide elucidated using the cambridge structural database.

PubMed

Ichikawa, Akio; Ono, Hiroshi; Mikata, Yuji

2015-07-16

Conformations of the crystalline 3,3,3-trifluoro-2-methoxy-2-phenylpropanamide derivatives (MTPA amides) deposited in the Cambridge Structural Database (CSD) were examined statistically as Racid-enantiomers. The majority of dihedral angles (48/58, ca. 83%) of the amide carbonyl groups and the trifluoromethyl groups ranged from -30° to 0° with an average angle θ1 of -13°. The other conformational properties were also clarified: (1) one of the fluorine atoms was antiperiplanar (ap) to the amide carbonyl group, forming a staggered conformation; (2) the MTPA amides prepared from primary amines showed a Z form in amide moieties; (3) in the case of the MTPA amide prepared from a primary amine possessing secondary alkyl groups (i.e., Mosher-type MTPA amide), the dihedral angles between the methine groups and the carbonyl groups were syn and indicative of a moderate conformational flexibility; (4) the phenyl plane was inclined from the O-Cchiral bond of the methoxy moiety with an average dihedral angle θ2 of +21°; (5) the methyl group of the methoxy moiety was ap to the ipso-carbon atom of the phenyl group.

Interactive and Versatile Navigation of Structural Databases.

PubMed

Korb, Oliver; Kuhn, Bernd; Hert, Jérôme; Taylor, Neil; Cole, Jason; Groom, Colin; Stahl, Martin

2016-05-12

We present CSD-CrossMiner, a novel tool for pharmacophore-based searches in crystal structure databases. Intuitive pharmacophore queries describing, among others, protein-ligand interaction patterns, ligand scaffolds, or protein environments can be built and modified interactively. Matching crystal structures are overlaid onto the query and visualized as soon as they are available, enabling the researcher to quickly modify a hypothesis on the fly. We exemplify the utility of the approach by showing applications relevant to real-world drug discovery projects, including the identification of novel fragments for a specific protein environment or scaffold hopping. The ability to concurrently search protein-ligand binding sites extracted from the Protein Data Bank (PDB) and small organic molecules from the Cambridge Structural Database (CSD) using the same pharmacophore query further emphasizes the flexibility of CSD-CrossMiner. We believe that CSD-CrossMiner closes an important gap in mining structural data and will allow users to extract more value from the growing number of available crystal structures.

Structural analysis of the coordination of dinitrogen to transition metal complexes.

PubMed

Peigné, Benjamin; Aullón, Gabriel

2015-06-01

Transition-metal complexes show a wide variety of coordination modes for the nitrogen molecule. A structural database study has been undertaken for dinitrogen complexes, and geometrical parameters around the L(n)M-N2 unit are retrieved from the Cambridge Structural Database. These data were classified in families of compounds, according to metal properties, to determine the degree of lengthening for the dinitrogen bonding. The importance of the nature of the metal center, such as coordination number and electronic configuration, is reported. Our study reveals poor activation by coordination of dinitrogen in mononuclear complexes, always having end-on coordination. However, partial weakening of nitrogen-nitrogen bonding is found for end-on binuclear complexes, whereas side-on complexes can be completely activated.

Hydrogen-bond coordination in organic crystal structures: statistics, predictions and applications.

PubMed

Galek, Peter T A; Chisholm, James A; Pidcock, Elna; Wood, Peter A

2014-02-01

Statistical models to predict the number of hydrogen bonds that might be formed by any donor or acceptor atom in a crystal structure have been derived using organic structures in the Cambridge Structural Database. This hydrogen-bond coordination behaviour has been uniquely defined for more than 70 unique atom types, and has led to the development of a methodology to construct hypothetical hydrogen-bond arrangements. Comparing the constructed hydrogen-bond arrangements with known crystal structures shows promise in the assessment of structural stability, and some initial examples of industrially relevant polymorphs, co-crystals and hydrates are described.

Supramolecular architectures constructed through self-assembly of a chalcone and substituted diazo-β-diketones

NASA Astrophysics Data System (ADS)

Prajapati, R.; Mishra, L.; Grabowski, S. J.; Govil, G.; Dubey, S. K.

2008-05-01

Organic compounds namely pyridyl chalcone viz. 3-[4-(3-oxo-3-pyridin-2-yl-propenyl)-phenyl]-1-pyridin-2-yl-propenone (L 1), p-cholorophenyldiazopentane-2,4-dione (L 2) and p-methyl phenyldiazopentane-2,4-dione (L 3) have been characterized by their single-crystal X-ray crystallographic studies. Several structural motifs resulting upon their self-association through probable non-covalent interactions have been discussed. The studies of related motifs found in Cambridge Structural Database are performed and the results are related to the structural data obtained for crystal structures reported here in.

A combined theoretical and Cambridge Structural Database study of π-hole pnicogen bonding complexes between electron rich molecules and both nitro compounds and inorganic bromides (YO2Br, Y = N, P, and As).

PubMed

Bauzá, Antonio; Ramis, Rafael; Frontera, Antonio

2014-04-17

Quantum calculations at the DFT-D3/def2-TZVPD level of theory have been used to examine complexes between O2YBr (Y═N, P, and As) molecules and several Lewis bases, that is, NH3, H2O, and HF. The interactions of the lone pair of the ammonia, water, and hydrogen fluoride with the σ-hole and π-hole of O2YBr molecules have been considered. In general, the complexes where the Lewis base lone pair interacts with the π-hole are more favorable than those with σ-hole. The nature of the interactions has been characterized with the Bader theory of atoms in molecules (AIM). We have also studied the ability of trifluoronitromethane and nitromethane to interact with anions using their π-hole along with an analysis the Cambridge Structural Database. We have found a large number of hits that provide strong experimental support for ability of the nitryl (-NO2) group to interact with anions and Lewis bases. In some X-ray structures, the π-hole interaction is crucial in the crystal packing and has a strong influence in the solid state architecture of the complexes. Finally, due to the relevance in atmospheric chemistry, we have studied noncovalent σ/π-hole complexes of nitryl bromide with ozone.

Generation of crystal structures using known crystal structures as analogues

PubMed Central

Cole, Jason C.; Groom, Colin R.; Read, Murray G.; Giangreco, Ilenia; McCabe, Patrick; Reilly, Anthony M.; Shields, Gregory P.

2016-01-01

This analysis attempts to answer the question of whether similar molecules crystallize in a similar manner. An analysis of structures in the Cambridge Structural Database shows that the answer is yes – sometimes they do, particularly for single-component structures. However, one does need to define what we mean by similar in both cases. Building on this observation we then demonstrate how this correlation between shape similarity and packing similarity can be used to generate potential lattices for molecules with no known crystal structure. Simple intermolecular interaction potentials can be used to minimize these potential lattices. Finally we discuss the many limitations of this approach. PMID:27484374

The use of small-molecule structures to complement protein–ligand crystal structures in drug discovery

PubMed Central

Cole, Jason C.

2017-01-01

Many ligand-discovery stories tell of the use of structures of protein–ligand complexes, but the contribution of structural chemistry is such a core part of finding and improving ligands that it is often overlooked. More than 800 000 crystal structures are available to the community through the Cambridge Structural Database (CSD). Individually, these structures can be of tremendous value and the collection of crystal structures is even more helpful. This article provides examples of how small-molecule crystal structures have been used to complement those of protein–ligand complexes to address challenges ranging from affinity, selectivity and bioavailability though to solubility. PMID:28291759

SInCRe—structural interactome computational resource for Mycobacterium tuberculosis

PubMed Central

Metri, Rahul; Hariharaputran, Sridhar; Ramakrishnan, Gayatri; Anand, Praveen; Raghavender, Upadhyayula S.; Ochoa-Montaño, Bernardo; Higueruelo, Alicia P.; Sowdhamini, Ramanathan; Chandra, Nagasuma R.; Blundell, Tom L.; Srinivasan, Narayanaswamy

2015-01-01

We have developed an integrated database for Mycobacterium tuberculosis H37Rv (Mtb) that collates information on protein sequences, domain assignments, functional annotation and 3D structural information along with protein–protein and protein–small molecule interactions. SInCRe (Structural Interactome Computational Resource) is developed out of CamBan (Cambridge and Bangalore) collaboration. The motivation for development of this database is to provide an integrated platform to allow easily access and interpretation of data and results obtained by all the groups in CamBan in the field of Mtb informatics. In-house algorithms and databases developed independently by various academic groups in CamBan are used to generate Mtb-specific datasets and are integrated in this database to provide a structural dimension to studies on tuberculosis. The SInCRe database readily provides information on identification of functional domains, genome-scale modelling of structures of Mtb proteins and characterization of the small-molecule binding sites within Mtb. The resource also provides structure-based function annotation, information on small-molecule binders including FDA (Food and Drug Administration)-approved drugs, protein–protein interactions (PPIs) and natural compounds that bind to pathogen proteins potentially and result in weakening or elimination of host–pathogen protein–protein interactions. Together they provide prerequisites for identification of off-target binding. Database URL: http://proline.biochem.iisc.ernet.in/sincre PMID:26130660

Bioactive focus in conformational ensembles: a pluralistic approach

NASA Astrophysics Data System (ADS)

Habgood, Matthew

2017-12-01

Computational generation of conformational ensembles is key to contemporary drug design. Selecting the members of the ensemble that will approximate the conformation most likely to bind to a desired target (the bioactive conformation) is difficult, given that the potential energy usually used to generate and rank the ensemble is a notoriously poor discriminator between bioactive and non-bioactive conformations. In this study an approach to generating a focused ensemble is proposed in which each conformation is assigned multiple rankings based not just on potential energy but also on solvation energy, hydrophobic or hydrophilic interaction energy, radius of gyration, and on a statistical potential derived from Cambridge Structural Database data. The best ranked structures derived from each system are then assembled into a new ensemble that is shown to be better focused on bioactive conformations. This pluralistic approach is tested on ensembles generated by the Molecular Operating Environment's Low Mode Molecular Dynamics module, and by the Cambridge Crystallographic Data Centre's conformation generator software.

The Cambridge Centre for Ageing and Neuroscience (Cam-CAN) data repository: Structural and functional MRI, MEG, and cognitive data from a cross-sectional adult lifespan sample.

PubMed

Taylor, Jason R; Williams, Nitin; Cusack, Rhodri; Auer, Tibor; Shafto, Meredith A; Dixon, Marie; Tyler, Lorraine K; Cam-Can; Henson, Richard N

2017-01-01

This paper describes the data repository for the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) initial study cohort. The Cam-CAN Stage 2 repository contains multi-modal (MRI, MEG, and cognitive-behavioural) data from a large (approximately N=700), cross-sectional adult lifespan (18-87years old) population-based sample. The study is designed to characterise age-related changes in cognition and brain structure and function, and to uncover the neurocognitive mechanisms that support healthy cognitive ageing. The database contains raw and preprocessed structural MRI, functional MRI (active tasks and resting state), and MEG data (active tasks and resting state), as well as derived scores from cognitive behavioural experiments spanning five broad domains (attention, emotion, action, language, and memory), and demographic and neuropsychological data. The dataset thus provides a depth of neurocognitive phenotyping that is currently unparalleled, enabling integrative analyses of age-related changes in brain structure, brain function, and cognition, and providing a testbed for novel analyses of multi-modal neuroimaging data. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Discovering H-bonding rules in crystals with inductive logic programming.

PubMed

Ando, Howard Y; Dehaspe, Luc; Luyten, Walter; Van Craenenbroeck, Elke; Vandecasteele, Henk; Van Meervelt, Luc

2006-01-01

In the domain of crystal engineering, various schemes have been proposed for the classification of hydrogen bonding (H-bonding) patterns observed in 3D crystal structures. In this study, the aim is to complement these schemes with rules that predict H-bonding in crystals from 2D structural information only. Modern computational power and the advances in inductive logic programming (ILP) can now provide computational chemistry with the opportunity for extracting structure-specific rules from large databases that can be incorporated into expert systems. ILP technology is here applied to H-bonding in crystals to develop a self-extracting expert system utilizing data in the Cambridge Structural Database of small molecule crystal structures. A clear increase in performance was observed when the ILP system DMax was allowed to refer to the local structural environment of the possible H-bond donor/acceptor pairs. This ability distinguishes ILP from more traditional approaches that build rules on the basis of global molecular properties.

Persistent hydrogen bonding in polymorphic crystal structures.

PubMed

Galek, Peter T A; Fábián, László; Allen, Frank H

2009-02-01

The significance of hydrogen bonding and its variability in polymorphic crystal structures is explored using new automated structural analysis methods. The concept of a chemically equivalent hydrogen bond is defined, which may be identified in pairs of structures, revealing those types of bonds that may persist, or not, in moving from one polymorphic form to another. Their frequency and nature are investigated in 882 polymorphic structures from the Cambridge Structural Database. A new method to compare conformations of equivalent molecules is introduced and applied to derive distinct subsets of conformational and packing polymorphs. The roles of chemical functionality and hydrogen-bond geometry in persistent interactions are systematically explored. Detailed structural comparisons reveal a large majority of persistent hydrogen bonds that are energetically crucial to structural stability.

SPLICE: A program to assemble partial query solutions from three-dimensional database searches into novel ligands

NASA Astrophysics Data System (ADS)

Ho, Chris M. W.; Marshall, Garland R.

1993-12-01

SPLICE is a program that processes partial query solutions retrieved from 3D, structural databases to generate novel, aggregate ligands. It is designed to interface with the database searching program FOUNDATION, which retrieves fragments containing any combination of a user-specified minimum number of matching query elements. SPLICE eliminates aspects of structures that are physically incapable of binding within the active site. Then, a systematic rule-based procedure is performed upon the remaining fragments to ensure receptor complementarity. All modifications are automated and remain transparent to the user. Ligands are then assembled by linking components into composite structures through overlapping bonds. As a control experiment, FOUNDATION and SPLICE were used to reconstruct a know HIV-1 protease inhibitor after it had been fragmented, reoriented, and added to a sham database of fifty different small molecules. To illustrate the capabilities of this program, a 3D search query containing the pharmacophoric elements of an aspartic proteinase-inhibitor crystal complex was searched using FOUNDATION against a subset of the Cambridge Structural Database. One hundred thirty-one compounds were retrieved, each containing any combination of at least four query elements. Compounds were automatically screened and edited for receptor complementarity. Numerous combinations of fragments were discovered that could be linked to form novel structures, containing a greater number of pharmacophoric elements than any single retrieved fragment.

Inorganic bromine in organic molecular crystals: Database survey and four case studies

NASA Astrophysics Data System (ADS)

Nemec, Vinko; Lisac, Katarina; Stilinović, Vladimir; Cinčić, Dominik

2017-01-01

We present a Cambridge Structural Database and experimental study of multicomponent molecular crystals containing bromine. The CSD study covers supramolecular behaviour of bromide and tribromide anions as well as halogen bonded dibromine molecules in crystal structures of organic salts and cocrystals, and a study of the geometries and complexities in polybromide anion systems. In addition, we present four case studies of organic structures with bromide, tribromide and polybromide anions as well as the neutral dibromine molecule. These include the first observed crystal with diprotonated phenazine, a double salt of phenazinium bromide and tribromide, a cocrystal of 4-methoxypyridine with the neutral dibromine molecule as a halogen bond donor, as well as bis(4-methoxypyridine)bromonium polybromide. Structural features of the four case studies are in the most part consistent with the statistically prevalent behaviour indicated by the CSD study for given bromine species, although they do exhibit some unorthodox structural features and in that indicate possible supramolecular causes for aberrations from the statistically most abundant (and presumably most favourable) geometries.

Two rhodamine 6G derivative compounds: a structural and fluorescence single-crystal study.

PubMed

Di Paolo, Matias; Bossi, Mariano L; Baggio, Ricardo; Suarez, Sebastián A

2016-10-01

The synthesis, characterization, structural analysis and fluorescence properties of two rhodamine 6G derivatives are described, namely a propargylamine derivative, 3',6'-bis(ethylamino)-2',7'-dimethyl-2-(methylcyanide)spiro[isoindole-1,9'-xanthen]-3(2H)-one (I), and a γ-aminobutyric acid (GABA) derivative, 3',6'-bis(ethylamino)-2',7'-dimethyl-3-oxospiro[isoindole-1,9'-xanthen]-2(3H)-yl)butyricacid (II). Both structures are compared with four similar ones from the Cambridge Structural Database (CSD), and the interactions involved in the stabilization are analyzed using the atoms in molecules (AIM) theory. Finally, a single-crystal in-situ reaction study is presented, carried out by fluorescence methods, which enabled the `opening' of the spirolactam ring in the solid phase.

The CH/π hydrogen bond: Implication in chemistry

NASA Astrophysics Data System (ADS)

Nishio, M.

2012-06-01

The CH/π hydrogen bond is the weakest extreme of hydrogen bonds that occurs between a soft acid CH and a soft base π-system. Implication in chemistry of the CH/π hydrogen bond includes issues of conformation, crystal packing, and specificity in host/guest complexes. The result obtained by analyzing the Cambridge Structural Database is reviewed. The peculiar axial preference of isopropyl group in α-phellandrene and folded conformation of levopimaric acid have been explained in terms of the CH/π hydrogen bond, by high-level ab initio MO calculations. Implication of the CH/π hydrogen bond in structural biology is also discussed, briefly.

Parameters for the RM1 Quantum Chemical Calculation of Complexes of the Trications of Thulium, Ytterbium and Lutetium

PubMed Central

Filho, Manoel A. M.; Dutra, José Diogo L.; Rocha, Gerd B.; Simas, Alfredo M.

2016-01-01

The RM1 quantum chemical model for the calculation of complexes of Tm(III), Yb(III) and Lu(III) is advanced. Subsequently, we tested the models by fully optimizing the geometries of 126 complexes. We then compared the optimized structures with known crystallographic ones from the Cambridge Structural Database. Results indicate that, for thulium complexes, the accuracy in terms of the distances between the lanthanide ion and its directly coordinated atoms is about 2%. Corresponding results for ytterbium and lutetium are both 3%, levels of accuracy useful for the design of lanthanide complexes, targeting their countless applications. PMID:27223475

Spacer conformation in biologically active molecules. Part 1. Structure and conformational preferences of 2-substituted benzoxazoles

NASA Astrophysics Data System (ADS)

Czylkowski, R.; Karolak-Wojciechowska, J.; Mrozek, A.; Yalçin, I.; Aki-Şener, E.

2001-12-01

The mutual position of two pharmacophoric elements in flexible biologically active molecules depends on the spacer conformation. This is true even for a two-atomic chain put to use as a spacer. It was established for 2-substituted-benzoxazoles containing two aromatic centres joined by -CH2-X- (X=S or O). From crystallographic studies of four molecules it was found that the role of heteroatom is essential for the whole molecule conformation. The spacer with X=S adopts the (-)synclinal conformation while for X=O the (+)antiperiplanar one. Such preferences were also found in the statistical data from Cambridge Structural Database (CSD).

PURY: a database of geometric restraints of hetero compounds for refinement in complexes with macromolecular structures.

PubMed

Andrejasic, Miha; Praaenikar, Jure; Turk, Dusan

2008-11-01

The number and variety of macromolecular structures in complex with ;hetero' ligands is growing. The need for rapid delivery of correct geometric parameters for their refinement, which is often crucial for understanding the biological relevance of the structure, is growing correspondingly. The current standard for describing protein structures is the Engh-Huber parameter set. It is an expert data set resulting from selection and analysis of the crystal structures gathered in the Cambridge Structural Database (CSD). Clearly, such a manual approach cannot be applied to the vast and ever-growing number of chemical compounds. Therefore, a database, named PURY, of geometric parameters of chemical compounds has been developed, together with a server that accesses it. PURY is a compilation of the whole CSD. It contains lists of atom classes and bonds connecting them, as well as angle, chirality, planarity and conformation parameters. The current compilation is based on CSD 5.28 and contains 1978 atom classes and 32,702 bonding, 237,068 angle, 201,860 dihedral and 64,193 improper geometric restraints. Analysis has confirmed that the restraints from the PURY database are suitable for use in macromolecular crystal structure refinement and should be of value to the crystallographic community. The database can be accessed through the web server http://pury.ijs.si/, which creates topology and parameter files from deposited coordinates in suitable forms for the refinement programs MAIN, CNS and REFMAC. In the near future, the server will move to the CSD website http://pury.ccdc.cam.ac.uk/.

Validation and extraction of molecular-geometry information from small-molecule databases.

PubMed

Long, Fei; Nicholls, Robert A; Emsley, Paul; Graǽulis, Saulius; Merkys, Andrius; Vaitkus, Antanas; Murshudov, Garib N

2017-02-01

A freely available small-molecule structure database, the Crystallography Open Database (COD), is used for the extraction of molecular-geometry information on small-molecule compounds. The results are used for the generation of new ligand descriptions, which are subsequently used by macromolecular model-building and structure-refinement software. To increase the reliability of the derived data, and therefore the new ligand descriptions, the entries from this database were subjected to very strict validation. The selection criteria made sure that the crystal structures used to derive atom types, bond and angle classes are of sufficiently high quality. Any suspicious entries at a crystal or molecular level were removed from further consideration. The selection criteria included (i) the resolution of the data used for refinement (entries solved at 0.84 Å resolution or higher) and (ii) the structure-solution method (structures must be from a single-crystal experiment and all atoms of generated molecules must have full occupancies), as well as basic sanity checks such as (iii) consistency between the valences and the number of connections between atoms, (iv) acceptable bond-length deviations from the expected values and (v) detection of atomic collisions. The derived atom types and bond classes were then validated using high-order moment-based statistical techniques. The results of the statistical analyses were fed back to fine-tune the atom typing. The developed procedure was repeated four times, resulting in fine-grained atom typing, bond and angle classes. The procedure will be repeated in the future as and when new entries are deposited in the COD. The whole procedure can also be applied to any source of small-molecule structures, including the Cambridge Structural Database and the ZINC database.

Suicide amongst Cambridge University students 1970-1996.

PubMed

Collins, I P; Paykel, E S

2000-03-01

Anecdote, media coverage and earlier research suggest that the rate of suicide amongst students at Cambridge and Oxford Universities is unduly high. There is also a popular belief that student suicide is common at examination times. Student deaths at the University of Cambridge were identified using the University database. The cause of death was determined by reference to death certificates and coroners' inquest records. We identified 157 student deaths during academic years 1970-1996, of which 36 appeared to be suicides. The overall suicide rate was 11.3/100,000 person years at risk. Suicide rates were similar to those seen amongst 15- to 24-year-olds in the general population. There were non-significant trends for male postgraduates to be over-represented and first-year undergraduates under-represented. Examination times were not associated with excess suicide. Suicide rates in University of Cambridge students do not appear to be unduly high.

Visualization of Hyperconjugation and Subsequent Structural Distortions through 3D Printing of Crystal Structures.

PubMed

Mithila, Farha J; Oyola-Reynoso, Stephanie; Thuo, Martin M; Atkinson, Manza Bj

2016-01-01

Structural distortions due to hyperconjugation in organic molecules, like norbornenes, are well captured through X-ray crystallographic data, but are sometimes difficult to visualize especially for those applying chemical knowledge and are not chemists. Crystal structure from the Cambridge database were downloaded and converted to .stl format. The structures were then printed at the desired scale using a 3D printer. Replicas of the crystal structures were accurately reproduced in scale and any resulting distortions were clearly visible from the macroscale models. Through space interactions or effect of through space hyperconjugation was illustrated through loss of symmetry or distortions thereof. The norbornene structures exhibits distortion that cannot be observed through conventional ball and stick modelling kits. We show that 3D printed models derived from crystallographic data capture even subtle distortions in molecules. We translate such crystallographic data into scaled-up models through 3D printing.

INFOSAM: A Sample Database Management System.

DTIC Science & Technology

1981-12-01

PROGRAM ELEMENT. PROJECT, TASA Sloan School of Management AREA WORK UNIT NUMBERS Massachusetts Institute of Technology Cambridge, MA 02139 II...96 NSETCAT .. ............................. 96 Inter -level Communication Databases .... 99 DEEAR ...................... 100 DVAR...Conceptual level, and the External level. The Inter - nal level represents a union of Hsu’s proposed Unary and Binary levels. The rationale for combining the

The Cambridge MRI database for animal models of Huntington disease.

PubMed

Sawiak, Stephen J; Morton, A Jennifer

2016-01-01

We describe the Cambridge animal brain magnetic resonance imaging repository comprising 400 datasets to date from mouse models of Huntington disease. The data include raw images as well as segmented grey and white matter images with maps of cortical thickness. All images and phenotypic data for each subject are freely-available without restriction from (http://www.dspace.cam.ac.uk/handle/1810/243361/). Software and anatomical population templates optimised for animal brain analysis with MRI are also available from this site. Copyright © 2015. Published by Elsevier Inc.

Remarkable features in lattice-parameter ratios of crystals. II. Monoclinic and triclinic crystals.

PubMed

de Gelder, R; Janner, A

2005-06-01

The frequency distributions of monoclinic crystals as a function of the lattice-parameter ratios resemble the corresponding ones of orthorhombic crystals: an exponential component, with more or less pronounced sharp peaks, with in general the most important peak at the ratio value 1. In addition, the distribution as a function of the monoclinic angle beta has a sharp peak at 90 degrees and decreases sensibly at larger angles. Similar behavior is observed for the three triclinic angular parameters alpha, beta and gamma, with characteristic differences between the organic and metal-organic, bio-macromolecular and inorganic crystals, respectively. The general behavior observed for the hexagonal, tetragonal, orthorhombic, monoclinic and triclinic crystals {in the first part of this series [de Gelder & Janner (2005). Acta Cryst. B61, 287-295] and in the present case} is summarized and commented. The data involved represent 366 800 crystals, with lattice parameters taken from the Cambridge Structural Database, CSD (294 400 entries), the Protein Data Bank, PDB (18 800 entries), and the Inorganic Crystal Structure Database, ICSD (53 600 entries). A new general structural principle is suggested.

Trends in active pharmaceutical ingredient salt selection based on analysis of the Orange Book database.

PubMed

Paulekuhn, G Steffen; Dressman, Jennifer B; Saal, Christoph

2007-12-27

The Orange Book database published by the U.S. Drug and Food Administration (FDA) was analyzed for the frequency of occurrence of different counterions used for the formation of pharmaceutical salts. The data obtained from the present analysis of the Orange Book are compared to reviews of the Cambridge Structural Database (CSD) and of the Martindale "The Extra Pharmacopoeia". As well as showing overall distributions of counterion usage, results are broken down into 5-year increments to identify trends in counterion selection. Chloride ions continue to be the most frequently utilized anionic counterions for the formation of salts as active pharmaceutical ingredients (APIs), while sodium ions are most widely utilized for the formation of salts starting from acidic molecules. A strong trend toward a wider variety of counterions over the past decade is observed. This trend can be explained by a stronger need to improve physical chemical properties of research and development compounds.

Consensus Knowledge Acquisition

DTIC Science & Technology

1989-12-01

ex- plicit the logical structure of their positions. Structured frameworks for analyzing 3 SOME USEFUL IDEAS 3 arguments ( Toulmin , 1958; Fogelin, 1982...358-87, 1987. Stefik M, et al., Beyond the chalkboard, CACM, 30:1, Jan 1987, pp. 32-47. Toulmin , S. The Uses of Argument. Cambridge, England: Cambridge University Press, 1958. 01

Cambridge Crystallographic Data Centre. II. Structural Data File

ERIC Educational Resources Information Center

Allen, F. H.; And Others

1973-01-01

The Cambridge Crystallographic Data Centre is concerned with the retrieval, evaluation, synthesis, and dissemination of structural data obtained by diffraction methods. This article (Part I is EJ053033) describes the work of the center and deals with the organization and maintenance of a computerized file of numeric crystallographic structural…

Estimation of vulnerability functions based on a global earthquake damage database

NASA Astrophysics Data System (ADS)

Spence, R. J. S.; Coburn, A. W.; Ruffle, S. J.

2009-04-01

Developing a better approach to the estimation of future earthquake losses, and in particular to the understanding of the inherent uncertainties in loss models, is vital to confidence in modelling potential losses in insurance or for mitigation. For most areas of the world there is currently insufficient knowledge of the current building stock for vulnerability estimates to be based on calculations of structural performance. In such areas, the most reliable basis for estimating vulnerability is performance of the building stock in past earthquakes, using damage databases, and comparison with consistent estimates of ground motion. This paper will present a new approach to the estimation of vulnerabilities using the recently launched Cambridge University Damage Database (CUEDD). CUEDD is based on data assembled by the Martin Centre at Cambridge University since 1980, complemented by other more-recently published and some unpublished data. The database assembles in a single, organised, expandable and web-accessible database, summary information on worldwide post-earthquake building damage surveys which have been carried out since the 1960's. Currently it contains data on the performance of more than 750,000 individual buildings, in 200 surveys following 40 separate earthquakes. The database includes building typologies, damage levels, location of each survey. It is mounted on a GIS mapping system and links to the USGS Shakemaps of each earthquake which enables the macroseismic intensity and other ground motion parameters to be defined for each survey and location. Fields of data for each building damage survey include: · Basic earthquake data and its sources · Details of the survey location and intensity and other ground motion observations or assignments at that location · Building and damage level classification, and tabulated damage survey results · Photos showing typical examples of damage. In future planned extensions of the database information on human casualties will also be assembled. The database also contains analytical tools enabling data from similar locations, building classes or ground motion levels to be assembled and thus vulnerability relationships derived for any chosen ground motion parameter, for a given class of building, and for particular countries or regions. The paper presents examples of vulnerability relationships for particular classes of buildings and regions of the world, together with the estimated uncertainty ranges. It will discuss the applicability of such vulnerability functions in earthquake loss assessment for insurance purposes or for earthquake risk mitigation.

Reactivity of 12-tungstophosphoric acid and its inhibitor potency toward Na+/K+-ATPase: A combined 31P NMR study, ab initio calculations and crystallographic analysis.

PubMed

Bošnjaković-Pavlović, Nada; Bajuk-Bogdanović, Danica; Zakrzewska, Joanna; Yan, Zeyin; Holclajtner-Antunović, Ivanka; Gillet, Jean-Michel; Spasojević-de Biré, Anne

2017-11-01

Influence of 12-tungstophosphoric acid (WPA) on conversion of adenosine triphosphate (ATP) to adenosine diphosphate (ADP) in the presence of Na + /K + -ATPase was monitored by 31 P NMR spectroscopy. It was shown that WPA exhibits inhibitory effect on Na + /K + -ATPase activity. In order to study WPA reactivity and intermolecular interactions between WPA oxygen atoms and different proton donor types (D=O, N, C), we have considered data for WPA based compounds from the Cambridge Structural Database (CSD), the Crystallographic Open Database (COD) and the Inorganic Crystal Structure Database (ICSD). Binding properties of Keggin's anion in biological systems are illustrated using Protein Data Bank (PDB). This work constitutes the first determination of theoretical Bader charges on polyoxotungstate compound via the Atom In Molecule theory. An analysis of electrostatic potential maps at the molecular surface and charge of WPA, resulting from DFT calculations, suggests that the preferred protonation site corresponds to WPA bridging oxygen. These results enlightened WPA chemical reactivity and its potential biological applications such as the inhibition of the ATPase activity. Copyright © 2017 Elsevier Inc. All rights reserved.

Conformation-dependent restraints for polynucleotides: I. Clustering of the geometry of the phosphodiester group

PubMed Central

Kowiel, Marcin; Brzezinski, Dariusz; Jaskolski, Mariusz

2016-01-01

The refinement of macromolecular structures is usually aided by prior stereochemical knowledge in the form of geometrical restraints. Such restraints are also used for the flexible sugar-phosphate backbones of nucleic acids. However, recent highly accurate structural studies of DNA suggest that the phosphate bond angles may have inadequate description in the existing stereochemical dictionaries. In this paper, we analyze the bonding deformations of the phosphodiester groups in the Cambridge Structural Database, cluster the studied fragments into six conformation-related categories and propose a revised set of restraints for the O-P-O bond angles and distances. The proposed restraints have been positively validated against data from the Nucleic Acid Database and an ultrahigh-resolution Z-DNA structure in the Protein Data Bank. Additionally, the manual classification of PO4 geometry is compared with geometrical clusters automatically discovered by machine learning methods. The machine learning cluster analysis provides useful insights and a practical example for general applications of clustering algorithms for automatic discovery of hidden patterns of molecular geometry. Finally, we describe the implementation and application of a public-domain web server for automatic generation of the proposed restraints. PMID:27521371

Characterization of molecular associations involving L-ornithine and α-ketoglutaric acid: crystal structure of L-ornithinium α-ketoglutarate.

PubMed

Allouchi, H; Céolin, R; Berthon, L; Tombret, F; Rietveld, I B

2014-07-01

The crystal structure of L-ornithinium α-ketoglutarate (C5H13N2O2, C5H5O5) has been solved by direct methods using single crystal X-ray diffraction data. It crystallizes in the monoclinic system, space group P21, unit cell parameters a=15.4326(3), b=5.2015(1), c=16.2067(3) Å and β=91.986(1)°, containing two independent pairs of molecular ions in the asymmetric unit. An extensive hydrogen-bond network and electrostatic charges due to proton transfer provide an important part of the cohesive energy of the crystal. The conformational versatility of L-ornithine and α-ketoglutaric acid is illustrated by the present results and crystal structures available from the Cambridge Structural Database. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Survey and analysis of crystal polymorphism in organic structures

PubMed Central

Kaur, Ramanpreet

2018-01-01

With the intention of producing the most comprehensive treatment of the prevalence of crystal polymorphism among structurally characterized materials, all polymorphic compounds flagged as such within the Cambridge Structural Database (CSD) are analysed and a list of crystallographically characterized organic polymorphic compounds is assembled. Classifying these structures into subclasses of anhydrates, salts, hydrates, non-hydrated solvates and cocrystals reveals that there are significant variations in polymorphism prevalence as a function of crystal type, a fact which has not previously been recognized in the literature. It is also shown that, as a percentage, polymorphic entries are decreasing temporally within the CSD, with the notable exception of cocrystals, which continue to rise at a rate that is a constant fraction of the overall entries. Some phenomena identified that require additional scrutiny include the relative prevalence of temperature-induced phase transitions among organic salts and the paucity of polymorphism in crystals with three or more chemical components. PMID:29765601

Structure-directing weak phosphoryl XH...O=P (X = C, N) hydrogen bonds in cyclic oxazaphospholidines and oxazaphosphinanes.

PubMed

van der Lee, A; Rolland, M; Marat, X; Virieux, D; Volle, J N; Pirat, J L

2008-04-01

The structures of six cyclic oxazaphospholidines and three cyclic oxazaphosphinanes have been determined and their supramolecular structures have been compared. The molecules differ with respect to the functional groups attached to the central five- or six-membered rings, but have one phosphoryl group in common. The predominant feature in the supramolecular structures is the existence of relatively weak intermolecular phosphoryl XH...O=P (X = C, N) hydrogen bonds, creating in nearly all cases linear zigzag or double molecular chains. The molecular chains are in general linked to each other via very weak CH...pi or usual hydrogen-bond interactions. A survey of the Cambridge Structural Database on similar XH...O=P interactions shows a very large flexibility of the XH...O angle, which is in agreement with the DFT calculation reported elsewhere. The strength of the XH...O=P interaction can therefore be considered as relatively weak to moderately strong, and is expected to play at least a role in the formation of secondary substructures.

Lattice energy calculation - A quick tool for screening of cocrystals and estimation of relative solubility. Case of flavonoids

NASA Astrophysics Data System (ADS)

Kuleshova, L. N.; Hofmann, D. W. M.; Boese, R.

2013-03-01

Cocrystals (or multicomponent crystals) have physico-chemical properties that are different from crystals of pure components. This is significant in drug development, since the desired properties, e.g. solubility, stability and bioavailability, can be tailored by binding two substances into a single crystal without chemical modification of an active component. Here, the FLEXCRYST program suite, implemented with a data mining force field, was used to estimate the relative stability and, consequently, the relative solubility of cocrystals of flavonoids vs their pure crystals, stored in the Cambridge Structural Database. The considerable potency of this approach for in silico screening of cocrystals, as well as their relative solubility, was demonstrated.

University of Iowa at TREC 2008 Legal and Relevance Feedback Tracks

DTIC Science & Technology

2008-11-01

Fellbaum, C, [ed.]. Wordnet: An Electronic Lexical Database. Cambridge : MIT Press, 1998. [3] Salton , G. (ed) (1971), The SMART Retrieval System...learning tools and techniques. 2nd Edition. San Francisco : Morgan Kaufmann, 2005. [5] Platt, J . Machines using Sequential Minimal Optimization. [ed.] B

Point Picking and Distributing on the Disc and Sphere

DTIC Science & Technology

2015-07-01

interesting application of geodesic subdivision is the design of domes, buildings, and structures (e.g., Spaceship Earth14 at Epcot, Walt Disney World; the...Computational Geometry in C. Cambridge (United Kingdom): Cambridge University Press; 1993. 41 14. Spaceship Earth. Walt Disney World; [accessed 2014

A Cognitive Architecture for Solving Ill-Structured Problems

DTIC Science & Technology

1997-08-01

R. C. (1982). Dynamic memory. Cambridge, Mass.: Cambridge University Press. Selfridge, 0. G., & Neisser , U . (1960). Pattern recognition by machine...Page 1 . In tro d u ctio n...1 1.1 Relevance to the ARI M ission ............................................................................... 1 1.2 Components of Analogy U se

Rhetorical Structure of Biochemistry Research Articles

ERIC Educational Resources Information Center

Kanoksilapatham, Budsaba

2005-01-01

This paper reports on the results of a move analysis [Swales, J. (1990). "Genre analysis." Cambridge: Cambridge University Press] of 60 biochemistry research articles. First, a corpus was systematically compiled to ensure that it represents core journals in the focused discipline. Then, coding reliability analysis was conducted to…

From molecule to solid: The prediction of organic crystal structures

NASA Astrophysics Data System (ADS)

Dzyabchenko, A. V.

2008-10-01

A method for predicting the structure of a molecular crystal based on the systematic search for a global potential energy minimum is considered. The method takes into account unequal occurrences of the structural classes of organic crystals and symmetry of the multidimensional configuration space. The programs of global minimization PMC, comparison of crystal structures CRYCOM, and approximation to the distributions of the electrostatic potentials of molecules FitMEP are presented as tools for numerically solving the problem. Examples of predicted structures substantiated experimentally and the experience of author’s participation in international tests of crystal structure prediction organized by the Cambridge Crystallographic Data Center (Cambridge, UK) are considered.

Review of Aircraft Crash Databases and Evaluation of the Probability of Aircraft Crashes on to a MAGLEV Guide-way: Technical Report

DOT National Transportation Integrated Search

1991-12-09

The System Safety & Security Division at The Volpe National Transportation System Center (VNTSC), Cambridge, MA is participating in an overall risk assessment study on the safety of High Speed Magnetic Levitation Transportation Systems ("MagLev"). Tr...

A single-molecule diode

NASA Astrophysics Data System (ADS)

Elbing, Mark; Ochs, Rolf; Koentopp, Max; Fischer, Matthias; von Hänisch, Carsten; Weigend, Florian; Evers, Ferdinand; Weber, Heiko B.; Mayor, Marcel

2005-06-01

We have designed and synthesized a molecular rod that consists of two weakly coupled electronic π -systems with mutually shifted energy levels. The asymmetry thus implied manifests itself in a current-voltage characteristic with pronounced dependence on the sign of the bias voltage, which makes the molecule a prototype for a molecular diode. The individual molecules were immobilized by sulfur-gold bonds between both electrodes of a mechanically controlled break junction, and their electronic transport properties have been investigated. The results indeed show diode-like current-voltage characteristics. In contrast to that, control experiments with symmetric molecular rods consisting of two identical π -systems did not show significant asymmetries in the transport properties. To investigate the underlying transport mechanism, phenomenological arguments are combined with calculations based on density functional theory. The theoretical analysis suggests that the bias dependence of the polarizability of the molecule feeds back into the current leading to an asymmetric shape of the current-voltage characteristics, similar to the phenomena in a semiconductor diode. Author contributions: F.E., H.B.W., and M.M. designed research; M.E., R.O., M.K., M.F., F.E., H.B.W., and M.M. performed research; M.E., R.O., M.K., M.F., C.v.H., F.W., F.E., H.B.W., and M.M. contributed new reagents/analytic tools; M.E., R.O., M.K., C.v.H., F.E., H.B.W., and M.M. analyzed data; and F.E., H.B.W., and M.M. wrote the paper.This paper was submitted directly (Track II) to the PNAS office.Abbreviations: A, acceptor; D, donor; MCB, mechanically controlled break junction.Data deposition: The atomic coordinates have been deposited in the Cambridge Structural Database, Cambridge Crystallographic Data Centre, Cambridge CB2 1EZ, United Kingdom (CSD reference no. 241632).

Data-driven high-throughput prediction of the 3-D structure of small molecules: review and progress. A response to the letter by the Cambridge Crystallographic Data Centre.

PubMed

Baldi, Pierre

2011-12-27

A response is presented to sentiments expressed in "Data-Driven High-Throughput Prediction of the 3-D Structure of Small Molecules: Review and Progress. A Response from The Cambridge Crystallographic Data Centre", recently published in the Journal of Chemical Information and Modeling, (1) which may give readers a misleading impression regarding significant impediments to scientific research posed by the CCDC.

Information Systems Technician Rating Stakeholders: Implications for Effective Performance

DTIC Science & Technology

2011-01-01

DeSanctis, and Borge Obel. (2006). Organizational Design: A Step-by-Step Approach. Cambridge, UK: Cambridge University Press. Carroll, G . R., and M...manpower, personnel, and training processes for managing the information systems technician (IT) rating and the effects of these different stakeholders...Strategic Human Resource Management and Management Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Organizational

Molecular Modeling and Experimental Investigations of Nonlinear Optical Compounds Monosubstituted Derivatives of Dicyanovinylbenzene

NASA Technical Reports Server (NTRS)

Timofeeva, Tatiana V.; Nesterov, Vladimir N.; Antipin, Mikhail Yu.; Clark, Ronald D.; Sanghadasa, Mohan; Cardelino, Beatriz H.; Moore, Craig E.; Frazier, Donald O.

1999-01-01

A search for potential nonlinear optical compounds was performed using the Cambridge Structure Database and molecular modeling. We investigated a series of monosubstituted derivatives of dicyanovinylbenzene, since the nonlinear optical (NLO) properties of such derivatives (o-methoxy-dicyanovinylbenzene, DIVA) were studied earlier. The molecular geometry of these compounds was investigated with x-ray analysis and discussed along with the results of molecular mechanics and ab initio quantum chemical calculations. The influence of crystal packing on the planarity of the molecules of this series has been revealed. Two new compounds from the series studied, ortho-F and para-Cl-dicyanovinylbenzene, according to powder measurements, were found to be NLO compounds in the crystal state about 10 times more active than urea. The peculiarities of crystal structure formation in the framework of balance between van der Waals and electrostatic interactions have been discussed. The crystal shape of DIVA and two new NLO compounds have been calculated on the basis of the known crystal structure.

Structural study of piracetam polymorphs and cocrystals: crystallography redetermination and quantum mechanics calculations.

PubMed

Tilborg, Anaëlle; Jacquemin, Denis; Norberg, Bernadette; Perpète, Eric; Michaux, Catherine; Wouters, Johan

2011-12-01

Pharmaceutical compounds are mostly developed as solid dosage forms containing a single-crystal form. It means that the selection of a particular crystal state for a given molecule is an important step for further clinical outlooks. In this context, piracetam, a pharmaceutical molecule known since the sixties for its nootropic properties, is considered in the present work. This molecule is analyzed using several experimental and theoretical approaches. First, the conformational space of the molecule has been systematically explored by performing a quantum mechanics scan of the two most relevant dihedral angles of the lateral chain. The predicted stable conformations have been compared to all the reported experimental geometries retrieved from the Cambridge Structural Database (CSD) covering polymorphs and cocrystals structures. In parallel, different batches of powders have been recrystallized. Under specific conditions, single crystals of polymorph (III) of piracetam have been obtained, an outcome confirmed by crystallographic analysis. © 2011 International Union of Crystallography. Printed in Singapore – all rights reserved.

Use of Crystal Structure Informatics for Defining the Conformational Space Needed for Predicting Crystal Structures of Pharmaceutical Molecules.

PubMed

Iuzzolino, Luca; Reilly, Anthony M; McCabe, Patrick; Price, Sarah L

2017-10-10

Determining the range of conformations that a flexible pharmaceutical-like molecule could plausibly adopt in a crystal structure is a key to successful crystal structure prediction (CSP) studies. We aim to use conformational information from the crystal structures in the Cambridge Structural Database (CSD) to facilitate this task. The conformations produced by the CSD Conformer Generator are reduced in number by considering the underlying rotamer distributions, an analysis of changes in molecular shape, and a minimal number of molecular ab initio calculations. This method is tested for five pharmaceutical-like molecules where an extensive CSP study has already been performed. The CSD informatics-derived set of crystal structure searches generates almost all the low-energy crystal structures previously found, including all experimental structures. The workflow effectively combines information on individual torsion angles and then eliminates the combinations that are too high in energy to be found in the solid state, reducing the resources needed to cover the solid-state conformational space of a molecule. This provides insights into how the low-energy solid-state and isolated-molecule conformations are related to the properties of the individual flexible torsion angles.

Correspondence: World Wide Web access to the British Universities Human Embryo Database

PubMed Central

AITON, JAMES F.; MCDONOUGH, ARIANA; MCLACHLAN, JOHN C.; SMART, STEVEN D.; WHITEN, SUSAN C.

1997-01-01

The British Universities Human Embryo Database has been created by merging information from the Walmsley Collection of Human Embryos at the School of Biological and Medical Sciences, University of St Andrews and from the Boyd Collection of Human Embryos at the Department of Anatomy, University of Cambridge. The database has been made available electronically on the Internet and World Wide Web browsers can be used to implement interactive access to the information stored in the British Universities Human Embryo Database. The database can, therefore, be accessed and searched from remote sites and specific embryos can be identified in terms of their location, age, developmental stage, plane of section, staining technique, and other parameters. It is intended to add information from other similar collections in the UK as it becomes available. PMID:9034891

NO3- anions can act as Lewis acid in the solid state

NASA Astrophysics Data System (ADS)

Bauzá, Antonio; Frontera, Antonio; Mooibroek, Tiddo J.

2017-02-01

Identifying electron donating and accepting moieties is crucial to understanding molecular aggregation, which is of pivotal significance to biology. Anions such as NO3- are typical electron donors. However, computations predict that the charge distribution of NO3- is anisotropic and minimal on nitrogen. Here we show that when the nitrate's charge is sufficiently dampened by resonating over a larger area, a Lewis acidic site emerges on nitrogen that can interact favourably with electron rich partners. Surveys of the Cambridge Structural Database and Protein Data Bank reveal geometric preferences of some oxygen and sulfur containing entities around a nitrate anion that are consistent with this `π-hole bonding' geometry. Computations reveal donor-acceptor orbital interactions that confirm the counterintuitive Lewis π-acidity of nitrate.

Task Effects on Linguistic Complexity and Accuracy: A Large-Scale Learner Corpus Analysis Employing Natural Language Processing Techniques

ERIC Educational Resources Information Center

Alexopoulou, Theodora; Michel, Marije; Murakami, Akira; Meurers, Detmar

2017-01-01

Large-scale learner corpora collected from online language learning platforms, such as the EF-Cambridge Open Language Database (EFCAMDAT), provide opportunities to analyze learner data at an unprecedented scale. However, interpreting the learner language in such corpora requires a precise understanding of tasks: How does the prompt and input of a…

Performance on Cambridge Neuropsychological Test Automated Battery Subtests Sensitive to Frontal Lobe Function in People with Autistic Disorder: Evidence from the Collaborative Programs of Excellence in Autism Network

ERIC Educational Resources Information Center

Ozonoff, Sally; Cook, Ian; Coon, Hilary; Dawson, Geraldine; Joseph, Robert M.; Klin, Ami; McMahon, William M.; Minshew, Nancy; Munson, Jeffrey A.

2004-01-01

Recent structural and functional imaging work, as well as neuropathology and neuropsychology studies, provide strong empirical support for the involvement of frontal cortex in autism. The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a computer-administered set of neuropsychological tests developed to examine specific components…

Efficient gradient-based Monte Carlo simulation of materials: Applications to amorphous Si and Fe and Ni clusters

NASA Astrophysics Data System (ADS)

Limbu, Dil; Biswas, Parthapratim

We present a simple and efficient Monte-Carlo (MC) simulation of Iron (Fe) and Nickel (Ni) clusters with N =5-100 and amorphous Silicon (a-Si) starting from a random configuration. Using Sutton-Chen and Finnis-Sinclair potentials for Ni (in fcc lattice) and Fe (in bcc lattice), and Stillinger-Weber potential for a-Si, respectively, the total energy of the system is optimized by employing MC moves that include both the stochastic nature of MC simulations and the gradient of the potential function. For both iron and nickel clusters, the energy of the configurations is found to be very close to the values listed in the Cambridge Cluster Database, whereas the maximum force on each cluster is found to be much lower than the corresponding value obtained from the optimized structural configurations reported in the database. An extension of the method to model the amorphous state of Si is presented and the results are compared with experimental data and those obtained from other simulation methods. The work is partially supported by the NSF under Grant Number DMR 1507166.

Full Spectrum Operations: An Analysis of Course Content at the Command and General Staff College

DTIC Science & Technology

2008-05-01

Dynamics of Military Revolutions 1300-2050. Cambridge: Cambridge University Press, 2001. Kolb , David A. Experiential Learning : Experience as the... experiential learning provides latitude for the student or instructor to deviate from the structured lesson plan and pursue alternate avenues to...their contribution. The cognitive learning environment of CGSC is best understood by reviewing the adult learning model and the experiential learning

IUCN/SSC Invasive Species Specialist Group (ISSG)

Science.gov Websites

., Barrios, V., Darwall, W.R.T. and Numa, C. (Editors). 2014. in the Eastern Mediterranean. Cambridge, UK the International Conference on Island Invasives. Edited by C. R. Veitch, M. N. Clout, and D. R. Towns combining and harmonizing data on IAS from a wide range of different databases and networks. The aim is to

Datacomputer and SIP Operations

DTIC Science & Technology

1979-03-30

developed in 1977 under ARPA Contract No. N0001 i4-76-C-0991 , as an application package which would utilize the Datacomputer [ Dorin & Sattley] for...Datacomputer Cambridge, Massachusetts, [ DORIN & EASTLAKE] R. H. Darin and Donald E. Eastlake, III; "Use of the Datacomputer in the Vela Seismological... DORIN & SATTLEY] Dorin , R.H. and Sattl^y, J.Z. Databases: Final Technical Report, Report No. CCAr.77-10, Computer America, 575

Molecular Modeling and Experimental Study of Nonlinear Optical Compounds: Mono-Substituted Derivatives of Dicyanovinylbenzene

NASA Technical Reports Server (NTRS)

Timofeeva, Tatyana V.; Nesterov, Vladimir N.; Antipin, Mikhael Y.; Clark, R. D.; Sanghadasa, M.; Cardelino, B. H.; Moore, C. E.; Frazier, Donald O.

2000-01-01

A search for potential nonlinear optical (NLO) compounds has been performed using the Cambridge Structural Database and molecular modeling. We have studied a series of mono-substituted derivatives of dicyanovinylbenzene as the NLO properties of one of its derivatives (o-methoxy-dicyanovinylbenzene, DIVA) were described earlier. The molecular geometry in the series of the compounds studied was investigated with an X- ray analysis and discussed along with results of molecular mechanics and ab initio quantum chemical calculations. The influence of crystal packing on the molecular planarity has been revealed. Two new compounds from the series studied were found to be active for second harmonic generation (SHG) in the powder. The measurements of SHG efficiency have shown that the o-F- and p-Cl-derivatives of dicyanovinylbenzene are about 10 and 20- times more active than urea, respectively. The peculiarities of crystal structure formation in the framework of balance between the van der Waals and electrostatic interactions have been discussed. The crystal morphology of DIVA and two new SHG-active compounds have been calculated on the basis of their known crystal structures.

Three dimensional model of severe acute respiratory syndrome coronavirus helicase ATPase catalytic domain and molecular design of severe acute respiratory syndrome coronavirus helicase inhibitors

NASA Astrophysics Data System (ADS)

Hoffmann, Marcin; Eitner, Krystian; von Grotthuss, Marcin; Rychlewski, Leszek; Banachowicz, Ewa; Grabarkiewicz, Tomasz; Szkoda, Tomasz; Kolinski, Andrzej

2006-05-01

The modeling of the severe acute respiratory syndrome coronavirus helicase ATPase catalytic domain was performed using the protein structure prediction Meta Server and the 3D Jury method for model selection, which resulted in the identification of 1JPR, 1UAA and 1W36 PDB structures as suitable templates for creating a full atom 3D model. This model was further utilized to design small molecules that are expected to block an ATPase catalytic pocket thus inhibit the enzymatic activity. Binding sites for various functional groups were identified in a series of molecular dynamics calculation. Their positions in the catalytic pocket were used as constraints in the Cambridge structural database search for molecules having the pharmacophores that interacted most strongly with the enzyme in a desired position. The subsequent MD simulations followed by calculations of binding energies of the designed molecules were compared to ATP identifying the most successful candidates, for likely inhibitors—molecules possessing two phosphonic acid moieties at distal ends of the molecule.

DG-AMMOS: a new tool to generate 3d conformation of small molecules using distance geometry and automated molecular mechanics optimization for in silico screening.

PubMed

Lagorce, David; Pencheva, Tania; Villoutreix, Bruno O; Miteva, Maria A

2009-11-13

Discovery of new bioactive molecules that could enter drug discovery programs or that could serve as chemical probes is a very complex and costly endeavor. Structure-based and ligand-based in silico screening approaches are nowadays extensively used to complement experimental screening approaches in order to increase the effectiveness of the process and facilitating the screening of thousands or millions of small molecules against a biomolecular target. Both in silico screening methods require as input a suitable chemical compound collection and most often the 3D structure of the small molecules has to be generated since compounds are usually delivered in 1D SMILES, CANSMILES or in 2D SDF formats. Here, we describe the new open source program DG-AMMOS which allows the generation of the 3D conformation of small molecules using Distance Geometry and their energy minimization via Automated Molecular Mechanics Optimization. The program is validated on the Astex dataset, the ChemBridge Diversity database and on a number of small molecules with known crystal structures extracted from the Cambridge Structural Database. A comparison with the free program Balloon and the well-known commercial program Omega generating the 3D of small molecules is carried out. The results show that the new free program DG-AMMOS is a very efficient 3D structure generator engine. DG-AMMOS provides fast, automated and reliable access to the generation of 3D conformation of small molecules and facilitates the preparation of a compound collection prior to high-throughput virtual screening computations. The validation of DG-AMMOS on several different datasets proves that generated structures are generally of equal quality or sometimes better than structures obtained by other tested methods.

Stereoselective virtual screening of the ZINC database using atom pair 3D-fingerprints.

PubMed

Awale, Mahendra; Jin, Xian; Reymond, Jean-Louis

2015-01-01

Tools to explore large compound databases in search for analogs of query molecules provide a strategically important support in drug discovery to help identify available analogs of any given reference or hit compound by ligand based virtual screening (LBVS). We recently showed that large databases can be formatted for very fast searching with various 2D-fingerprints using the city-block distance as similarity measure, in particular a 2D-atom pair fingerprint (APfp) and the related category extended atom pair fingerprint (Xfp) which efficiently encode molecular shape and pharmacophores, but do not perceive stereochemistry. Here we investigated related 3D-atom pair fingerprints to enable rapid stereoselective searches in the ZINC database (23.2 million 3D structures). Molecular fingerprints counting atom pairs at increasing through-space distance intervals were designed using either all atoms (16-bit 3DAPfp) or different atom categories (80-bit 3DXfp). These 3D-fingerprints retrieved molecular shape and pharmacophore analogs (defined by OpenEye ROCS scoring functions) of 110,000 compounds from the Cambridge Structural Database with equal or better accuracy than the 2D-fingerprints APfp and Xfp, and showed comparable performance in recovering actives from decoys in the DUD database. LBVS by 3DXfp or 3DAPfp similarity was stereoselective and gave very different analogs when starting from different diastereomers of the same chiral drug. Results were also different from LBVS with the parent 2D-fingerprints Xfp or APfp. 3D- and 2D-fingerprints also gave very different results in LBVS of folded molecules where through-space distances between atom pairs are much shorter than topological distances. 3DAPfp and 3DXfp are suitable for stereoselective searches for shape and pharmacophore analogs of query molecules in large databases. Web-browsers for searching ZINC by 3DAPfp and 3DXfp similarity are accessible at www.gdb.unibe.ch and should provide useful assistance to drug discovery projects. Graphical abstractAtom pair fingerprints based on through-space distances (3DAPfp) provide better shape encoding than atom pair fingerprints based on topological distances (APfp) as measured by the recovery of ROCS shape analogs by fp similarity.

Living on pyrrolic foundations - Advances in natural and artificial bioactive pyrrole derivatives.

PubMed

Domagala, Anna; Jarosz, Tomasz; Lapkowski, Mieczyslaw

2015-07-15

Pyrrole, a simple heterocyclic system, is an important building block for numerous biologically active compounds both natural and synthetic in origin, which boast an immense array of qualities, baleful and beneficial alike. The latter have given rise to a bountiful variety of pyrrole-based drugs, with many more being designed, developed and applied each year, as evidenced by the amount of entries in the Cambridge Structural Database skyrocketing from about six hundred in 2004 to more than a thousand over the course of the last decade. Particularly important in light of the ever-encroaching menace of drug-resistant bacteria, the vast progress in the field necessitates a sound organisational framework and summary - a task, to which we contribute this summary and checklist of the most recent developments, indicating the classes of compounds, which have attracted the most significant research attention. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Development of inert density mock materials for HMX

DOE PAGES

Yeager, John D.; Higginbotham Duque, Amanda L.; Shorty, Marvin; ...

2017-09-22

Inert surrogates or mocks for high explosives are commonly used in place of the real material for complex experiments or in situations where safety is a concern. We tested several materials as potential mocks for HMX in terms of density, thermal stability, and processability. Selection criteria were developed and a literature search was conducted primarily using the Cambridge Structural Database. Moreover, out of over 200 potentially acceptable materials, six were chosen for crystallization experiments and a suite of analytical characterization. Of these six, 5-iodo-2'-deoxyuridine, N,N'-bis(2,3,4,5,6-pentafluorophenyl)oxamide, and 2,3,4,5,6-pentafluorobenzamide all were found to be thermally stable at 150°C, matched HMX density asmore » a pressed pellet, and could be crystallized to appropriate particle sizes. These three materials are considered suitable inert density mocks for HMX and will be the subject of future testing.« less

Two tautomeric forms of 2-amino-5,6-dimethylpyrimidin-4-one.

PubMed

Hall, Victoria M; Bertke, Jeffery A; Swift, Jennifer A

2016-06-01

Derivatives of 4-hydroxypyrimidine are an important class of biomolecules. These compounds can undergo keto-enol tautomerization in solution, though a search of the Cambridge Structural Database shows a strong bias toward the 3H-keto tautomer in the solid state. Recrystallization of 2-amino-5,6-dimethyl-4-hydroxypyrimidine, C6H9N3O, from aqueous solution yielded triclinic crystals of the 1H-keto tautomer, denoted form (I). Though not apparent in the X-ray data, the IR spectrum suggests that small amounts of the 4-hydroxy tautomer are also present in the crystal. Monoclinic crystals of form (II), comprised of a 1:1 ratio of both the 1H-keto and the 3H-keto tautomers, were obtained from aqueous solutions containing uric acid. Forms (I) and (II) exhibit one-dimensional and three-dimensional hydrogen-bonding motifs, respectively.

A chiral diamine: practical implications of a three-stereoisomer cocrystallization.

PubMed

Dolinar, Brian S; Samedov, Kerim; Maloney, Andrew G P; West, Robert; Khrustalev, Victor N; Guzei, Ilia A

2018-01-01

A brief comparison of seven straightforward methods for molecular crystal-volume estimation revealed that their precisions are comparable. A chiral diamine, N 2 ,N 3 -bis[2,6-bis(propan-2-yl)phenyl]butane-2,3-diamine, C 28 H 44 N 2 , has been used to illustrate the application of the methods. Three stereoisomers of the diamine cocrystallize in the centrosymmetric space group P2 1 /c with Z' = 1.5. The molecules occupying general positions are RR and SS, whereas that residing on an inversion center is meso. This is one of only ten examples of three stereoisomers with two asymmetric atoms cocrystallizing together reported to the Cambridge Structural Database (CSD). The conformations of the SS/RR and meso molecules differ considerably and lead to statistically significantly different C(asymmetric)-C(asymmetric) bond lengths in the diastereomers. An advanced Python script-based CSD searching technique for chiral compounds is presented.

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

Yeager, John D.; Higginbotham Duque, Amanda L.; Shorty, Marvin

Inert surrogates or mocks for high explosives are commonly used in place of the real material for complex experiments or in situations where safety is a concern. We tested several materials as potential mocks for HMX in terms of density, thermal stability, and processability. Selection criteria were developed and a literature search was conducted primarily using the Cambridge Structural Database. Moreover, out of over 200 potentially acceptable materials, six were chosen for crystallization experiments and a suite of analytical characterization. Of these six, 5-iodo-2'-deoxyuridine, N,N'-bis(2,3,4,5,6-pentafluorophenyl)oxamide, and 2,3,4,5,6-pentafluorobenzamide all were found to be thermally stable at 150°C, matched HMX density asmore » a pressed pellet, and could be crystallized to appropriate particle sizes. These three materials are considered suitable inert density mocks for HMX and will be the subject of future testing.« less

Oriented matroids—combinatorial structures underlying loop quantum gravity

NASA Astrophysics Data System (ADS)

Brunnemann, Johannes; Rideout, David

2010-10-01

We analyze combinatorial structures which play a central role in determining spectral properties of the volume operator (Ashtekar A and Lewandowski J 1998 Adv. Theor. Math. Phys. 1 388) in loop quantum gravity (LQG). These structures encode geometrical information of the embedding of arbitrary valence vertices of a graph in three-dimensional Riemannian space and can be represented by sign strings containing relative orientations of embedded edges. We demonstrate that these signature factors are a special representation of the general mathematical concept of an oriented matroid (Ziegler G M 1998 Electron. J. Comb.; Björner A et al 1999 Oriented Matroids (Cambridge: Cambridge University Press)). Moreover, we show that oriented matroids can also be used to describe the topology (connectedness) of directed graphs. Hence, the mathematical methods developed for oriented matroids can be applied to the difficult combinatorics of embedded graphs underlying the construction of LQG. As a first application we revisit the analysis of Brunnemann and Rideout (2008 Class. Quantum Grav. 25 065001 and 065002), and find that enumeration of all possible sign configurations used there is equivalent to enumerating all realizable oriented matroids of rank 3 (Ziegler G M 1998 Electron. J. Comb.; Björner A et al 1999 Oriented Matroids (Cambridge: Cambridge University Press)), and thus can be greatly simplified. We find that for 7-valent vertices having no coplanar triples of edge tangents, the smallest non-zero eigenvalue of the volume spectrum does not grow as one increases the maximum spin jmax at the vertex, for any orientation of the edge tangents. This indicates that, in contrast to the area operator, considering large jmax does not necessarily imply large volume eigenvalues. In addition we give an outlook to possible starting points for rewriting the combinatorics of LQG in terms of oriented matroids.

Structural studies of crystalline forms of triamterene with carboxylic acid, GRAS and API molecules

PubMed Central

Rehman, Abida

2018-01-01

Pharmaceutical salt solvates (dimethyl sulfoxide, DMSO) of the drug triamterene with the coformers acetic, succinic, adipic, pimelic, azelaic and nicotinic acid and ibuprofen are prepared by liquid-assisted grinding and solvent-evaporative crystallization. The modified ΔpK a rule as proposed by Cruz-Cabeza [(2012 ▸). CrystEngComm, 14, 6362–6365] is in close agreement with the results of this study. All adducts were characterized by X-ray diffraction and thermal analytical techniques, including single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry and thermal gravimetric analysis. Hydrogen-bonded motifs combined to form a variety of extended tapes and sheets. Analysis of the crystal structures showed that all adducts existed as salt solvates and contained the amino­pyridinium–carboxyl­ate heterodimer, except for the solvate containing triamterene, ibuprofen and DMSO, as a result of the presence of a strong and stable hemitriamterenium duplex. A search of the Cambridge Structural Database (CSD 5.36, Version 1.18) to determine the frequency of occurrence of the putative supramolecular synthons found in this study showed good agreement with previous work. PMID:29755747

Quantum mechanics models of the methanol dimer: OH⋯O hydrogen bonds of β-d-glucose moieties from crystallographic data.

PubMed

Cintrón, Michael Santiago; Johnson, Glenn P; French, Alfred D

2017-04-18

The interaction of two methanol molecules, simplified models of carbohydrates and cellulose, was examined using a variety of quantum mechanics (QM) levels of theory. Energy plots for hydrogen bonding distance (H⋯O) and angle (OH⋯O) were constructed. All but two experimental structures were located in stabilized areas on the vacuum phase energy plots. Each of the 399 models was analyzed with Bader's atoms-in-molecules (AIM) theory, which showed a widespread ability by the dimer models to form OH⋯O hydrogen bonds that have bond paths and Bond Critical Points. Continuum solvation calculations suggest that a portion of the energy-stabilized structures could occur in the presence of water. A survey of the Cambridge Structural Database (CSD) for all donor-acceptor interactions in β-D-glucose moieties examined the similarities and differences among the hydroxyl groups and acetal oxygen atoms that participate in hydrogen bonds. Comparable behavior was observed for the O2H, O3H, O4H, and O6H hydroxyls, acting either as acceptors or donors. Ring O atoms showed distinct hydrogen bonding behavior that favored mid-length hydrogen bonds. Published by Elsevier Ltd.

ForceGen 3D structure and conformer generation: from small lead-like molecules to macrocyclic drugs

NASA Astrophysics Data System (ADS)

Cleves, Ann E.; Jain, Ajay N.

2017-05-01

We introduce the ForceGen method for 3D structure generation and conformer elaboration of drug-like small molecules. ForceGen is novel, avoiding use of distance geometry, molecular templates, or simulation-oriented stochastic sampling. The method is primarily driven by the molecular force field, implemented using an extension of MMFF94s and a partial charge estimator based on electronegativity-equalization. The force field is coupled to algorithms for direct sampling of realistic physical movements made by small molecules. Results are presented on a standard benchmark from the Cambridge Crystallographic Database of 480 drug-like small molecules, including full structure generation from SMILES strings. Reproduction of protein-bound crystallographic ligand poses is demonstrated on four carefully curated data sets: the ConfGen Set (667 ligands), the PINC cross-docking benchmark (1062 ligands), a large set of macrocyclic ligands (182 total with typical ring sizes of 12-23 atoms), and a commonly used benchmark for evaluating macrocycle conformer generation (30 ligands total). Results compare favorably to alternative methods, and performance on macrocyclic compounds approaches that observed on non-macrocycles while yielding a roughly 100-fold speed improvement over alternative MD-based methods with comparable performance.

Three-dimensional Structures of Carotenoids by X-ray Crystallography

NASA Astrophysics Data System (ADS)

Helliwell, Madeleine

The number of crystal structures of carotenoid molecules and carotenoid derivatives deposited in the Cambridge Crystallographic Data Centre [1] is still relatively small, but has increased compared with the previous survey [2]. The list is summarized in Table 1.

Local intensity area descriptor for facial recognition in ideal and noise conditions

NASA Astrophysics Data System (ADS)

Tran, Chi-Kien; Tseng, Chin-Dar; Chao, Pei-Ju; Ting, Hui-Min; Chang, Liyun; Huang, Yu-Jie; Lee, Tsair-Fwu

2017-03-01

We propose a local texture descriptor, local intensity area descriptor (LIAD), which is applied for human facial recognition in ideal and noisy conditions. Each facial image is divided into small regions from which LIAD histograms are extracted and concatenated into a single feature vector to represent the facial image. The recognition is performed using a nearest neighbor classifier with histogram intersection and chi-square statistics as dissimilarity measures. Experiments were conducted with LIAD using the ORL database of faces (Olivetti Research Laboratory, Cambridge), the Face94 face database, the Georgia Tech face database, and the FERET database. The results demonstrated the improvement in accuracy of our proposed descriptor compared to conventional descriptors [local binary pattern (LBP), uniform LBP, local ternary pattern, histogram of oriented gradients, and local directional pattern]. Moreover, the proposed descriptor was less sensitive to noise and had low histogram dimensionality. Thus, it is expected to be a powerful texture descriptor that can be used for various computer vision problems.

High pressure hydrogen stabilised by quantum nuclear motion

NASA Astrophysics Data System (ADS)

Needs, Richard; Monserrat, Bartomeu; Pickard, Chris

Hydrogen under extreme pressures is of fundamental interest, as it might exhibit exotic physical phenomena, and of practical interest, as it is a major component of many astrophysical objects. Structure searches have been successful at identifying promising candidates for the known phases of high pressure hydrogen. However, these searches have so far been restricted to the location of minima of the potential energy landscape. In this talk, we will describe a new structure searching method, ``saddle-point ab initio random structure searching'' (sp-AIRSS), that allows us to identify structures associated with saddle points of the potential energy landscape. Using sp-AIRSS, we find two new high-pressure hydrogen structures that exhibit a harmonic dynamical instability, but quantum and thermal anharmonic motion render them dynamically stable. These structures are formed by mixed layers of strongly and softly bound hydrogen molecules, and become thermodynamically competitive at the highest pressures reached in experiment. The experimental implications of these new structures will also be discussed. BM is supported by Robinson College, Cambridge, and the Cambridge Philosophical Society. RJN and CJP are supported by the Engineering and Physical Sciences Research Council (EPSRC) of the UK.

Crystallographic Data Centre Services and Publications.

ERIC Educational Resources Information Center

Cambridge Univ. (England). Chemical Lab.

The Cambridge Crystallographic Data Centre is concerned with the retrieval, evaluation, synthesis, and dissemination of structural data based on diffraction methods. The source of input is almost entirely primary journals. Bibliographic information and numeric data on crystal and molecular structures are on magnetic tapes. The bibliographic file…

Factor structure, validity and reliability of the Cambridge Worry Scale in a pregnant population.

PubMed

Green, Josephine M; Kafetsios, Konstantinos; Statham, Helen E; Snowdon, Claire M

2003-11-01

This article presents the Cambridge Worry Scale (CWS), a content-based measure for assessing worries, and discusses its psychometric properties based on a longitudinal study of 1,207 pregnant women. Principal components analysis revealed a four-factor structure of women's concerns during pregnancy: socio-medical, own health, socio-economic and relational. The measure demonstrated good reliability and validity. Total CWS scores were strongly associated with state and trait anxiety (convergent validity) but also had significant and unique predictive value for mood outcomes (discriminant validity). The CWS discriminated better between women with different reproductive histories than measures of state and trait anxiety. We conclude that the CWS is a reliable and valid tool for assessing the extent and content of worries in specific situations.

Floodplain management: Land acquisition versus preservation of historic buildings in Cambridge, Ontario, Canada

NASA Astrophysics Data System (ADS)

Bennett, Wendy J.; Mitchell, Bruce

1983-07-01

Non-structural adjustments in floodplain management are often avoided because they are seen to infringe on personal rights, adversely affect property values and restrict local tax bases. Land acquisition programs in urban areas encounter a further problem when they lead to demolition of buildings and other structures considered to have historical or architectural value. An experience in Cambridge, Ontario demonstrates that the potential conflict between flood damage reduction and historical preservation objectives can be exacerbated as a result of uncoordinated planning efforts, inflexibility in interpreting mandates, unclear roles for participating agencies, and lack of cooperation Many of these dilemmas can be resolved through consultation and discussion early in the planning process as well as through a willingness to be flexible and to search for a compromise

A multi-populations multi-strategies differential evolution algorithm for structural optimization of metal nanoclusters

NASA Astrophysics Data System (ADS)

Fan, Tian-E.; Shao, Gui-Fang; Ji, Qing-Shuang; Zheng, Ji-Wen; Liu, Tun-dong; Wen, Yu-Hua

2016-11-01

Theoretically, the determination of the structure of a cluster is to search the global minimum on its potential energy surface. The global minimization problem is often nondeterministic-polynomial-time (NP) hard and the number of local minima grows exponentially with the cluster size. In this article, a multi-populations multi-strategies differential evolution algorithm has been proposed to search the globally stable structure of Fe and Cr nanoclusters. The algorithm combines a multi-populations differential evolution with an elite pool scheme to keep the diversity of the solutions and avoid prematurely trapping into local optima. Moreover, multi-strategies such as growing method in initialization and three differential strategies in mutation are introduced to improve the convergence speed and lower the computational cost. The accuracy and effectiveness of our algorithm have been verified by comparing the results of Fe clusters with Cambridge Cluster Database. Meanwhile, the performance of our algorithm has been analyzed by comparing the convergence rate and energy evaluations with the classical DE algorithm. The multi-populations, multi-strategies mutation and growing method in initialization in our algorithm have been considered respectively. Furthermore, the structural growth pattern of Cr clusters has been predicted by this algorithm. The results show that the lowest-energy structure of Cr clusters contains many icosahedra, and the number of the icosahedral rings rises with increasing size.

Energetically Unfavorable Amide Conformations for N6-Acetyllysine Side Chains in Refined Protein Structures

PubMed Central

Genshaft, Alexander; Moser, Joe-Ann S.; D'Antonio, Edward L.; Bowman, Christine M.; Christianson, David W.

2013-01-01

The reversible acetylation of lysine to form N6-acetyllysine in the regulation of protein function is a hallmark of epigenetics. Acetylation of the positively charged amino group of the lysine side chain generates a neutral N-alkylacetamide moiety that serves as a molecular “switch” for the modulation of protein function and protein-protein interactions. We now report the analysis of 381 N6-acetyllysine side chain amide conformations as found in 79 protein crystal structures and 11 protein NMR structures deposited in the Protein Data Bank (PDB) of the Research Collaboratory for Structural Bioinformatics. We find that only 74.3% of N6-acetyllysine residues in protein crystal structures and 46.5% in protein NMR structures contain amide groups with energetically preferred trans or generously trans conformations. Surprisingly, 17.6% of N6-acetyllysine residues in protein crystal structures and 5.3% in protein NMR structures contain amide groups with energetically unfavorable cis or generously cis conformations. Even more surprisingly, 8.1% of N6-acetyllysine residues in protein crystal structures and 48.2% in NMR structures contain amide groups with energetically prohibitive twisted conformations that approach the transition state structure for cis-trans isomerization. In contrast, 109 unique N-alkylacetamide groups contained in 84 highly-accurate small molecule crystal structures retrieved from the Cambridge Structural Database exclusively adopt energetically preferred trans conformations. Therefore, we conclude that cis and twisted N6-acetyllysine amides in protein structures deposited in the PDB are erroneously modeled due to their energetically unfavorable or prohibitive conformations. PMID:23401043

On Directionality of Phrase Structure Building

ERIC Educational Resources Information Center

Chesi, Cristiano

2015-01-01

Minimalism in grammatical theorizing (Chomsky in "The minimalist program." MIT Press, Cambridge, 1995) led to simpler linguistic devices and a better focalization of the core properties of the structure building engine: a lexicon and a free (recursive) phrase formation operation, dubbed Merge, are the basic components that serve in…

VizieR Online Data Catalog: Companions to nearby stars from Pan-STARRS 1 (Deacon+, 2014)

NASA Astrophysics Data System (ADS)

Deacon, N. R.; Liu, M. C.; Magnier, E. A.; Aller, K. M.; Best, W. M. J.; Dupuy, T.; Bowler, B. P.; Mann, A. W.; Redstone, J. A.; Burgett, W. S.; Chambers, K. C.; Draper, P. W.; Flewelling, H.; Hodapp, K. W.; Kaiser, N.; Kudritzki, R.-P.; Morgan, J. S.; Metcalfe, N.; Price, P. A.; Tonry, J. L.; Wainscoat, R. J.

2017-04-01

Pan-STARRS 1 is a wide-field 1.8m telescope situated on Haleakala on Maui in the Hawaiian Islands. Run by a consortium of astronomical research institutions, it has been surveying the sky north of δ=-30° since 2010 May. Just over half of the telescope's operating time is reserved for the 3π Survey, a multi-filter, multi-epoch survey of three-fourths of the sky (~30,000 deg2). We conducted our search over several iterations of the Pan-STARRS 1 3π database. In all our searches we queried the most up-to-date Pan-STARRS 1 3π database using the Desktop Virtual Observatory software (Magnier et al. 2008, IAU Symp. 248, A Giant Step: from Milli- to Micro-arcsecond Astrometry (Cambridge: Cambridge Univ. Press), 553). Initially, our search involved combining 2MASS and Pan-STARRS 1 data to calculate proper motions in a similar process to that used by Deacon et al. (2011, J/AJ/142/77). For this PS1 + 2MASS search, we required that objects had more than one detection in the yP1 band. PS1 detections were required to have a significance greater than 5σ to be included in the astrometric and photometric solutions of their parent object. We also required that the objects be classified as good quality, point-source detections in both Pan-STARRS 1 and 2MASS. (10 data files).

Extreme oxatriquinanes and a record C-O bond length

NASA Astrophysics Data System (ADS)

Gunbas, Gorkem; Hafezi, Nema; Sheppard, William L.; Olmstead, Marilyn M.; Stoyanova, Irini V.; Tham, Fook S.; Meyer, Matthew P.; Mascal, Mark

2012-12-01

Oxatriquinanes are fused, tricyclic oxonium ions that are known to have exceptional stability compared to simple alkyl oxonium salts. C-O bonds in ethers are generally ˜1.43 Å in length, but oxatriquinane has been found to have C-O bond lengths of 1.54 Å. A search of the Cambridge Structural Database turned up no bona fide C-O bond length exceeding this value. Computational modelling of oxatriquinane alongside other alkyl oxonium ions indicated that the electronic consequences of molecular strain were primarily responsible for the observed bond elongation. We also show that substitution of the oxatriquinane ring system with alkyl groups of increasing steric demand pushes the C-O bond to unheard of distances, culminating in a tert-butyl derivative at a predicted 1.60 Å. Chemical synthesis and an X-ray crystallographic study of these compounds validated the results of the modelling work and, finally, an extraordinary 1.622 Å C-O bond was observed in 1,4,7-tri-tert-butyloxatriquinane.

Approximate Fluid-Structure Interaction Theories for Acoustic Echo Signal Predictions.

DTIC Science & Technology

1981-10-19

mations for Structure-Fluid Interaction Analysis," PA,,e𔃻n:s the Second International Symposium on Tnnovative Nijm,r;-a’ An.ti si in Applied ... Engineering Science, Montreal, Canada, June !,150, pi. 79-88. 8. Junger, M.C. and Feit, D., Sound. Structures and tht ir Tu,>i the MIT Press, Cambridge, MA

Brief Report: CANTAB Performance and Brain Structure in Pediatric Patients with Asperger Syndrome

ERIC Educational Resources Information Center

Kaufmann, Liane; Zotter, Sibylle; Pixner, Silvia; Starke, Marc; Haberlandt, Edda; Steinmayr-Gensluckner, Maria; Egger, Karl; Schocke, Michael; Weiss, Elisabeth M.; Marksteiner, Josef

2013-01-01

By merging neuropsychological (CANTAB/Cambridge Neuropsychological Test Automated Battery) and structural brain imaging data (voxel-based-morphometry) the present study sought to identify the neurocognitive correlates of executive functions in individuals with Asperger syndrome (AS) compared to healthy controls. Results disclosed subtle group…

Combined quantum mechanics and molecular mechanics simulation of Ca2+/ammonia solution based on the ONIOM-XS method: Octahedral coordination and implication to biology

NASA Astrophysics Data System (ADS)

Kerdcharoen, Teerakiat; Morokuma, Keiji

2003-05-01

An extension of the ONIOM (Own N-layered Integrated molecular Orbital and molecular Mechanics) method [M. Svensson, S. Humbel, R. D. J. Froese, T. Mutsubara, S. Sieber, and K. Morokuma, J. Phys. Chem. 100, 19357 (1996)] for simulation in the condensed phase, called ONIOM-XS (XS=eXtension to Solvation) [T. Kerdcharoen and K. Morokuma, Chem. Phys. Lett. 355, 257 (2002)], was applied to investigate the coordination of Ca2+ in liquid ammonia. A coordination number of 6 is found. Previous simulations based on pair potential or pair potential plus three-body correction gave values of 9 and 8.2, respectively. The new value is the same as the coordination number most frequently listed in the Cambridge Structural Database (CSD) and Protein Data Bank (PDB). N-Ca-N angular distribution reveals a near-octahedral coordination structure. Inclusion of many-body interactions (which amounts to 25% of the pair interactions) into the potential energy surface is essential for obtaining reasonable coordination number. Analyses of the metal coordination in water, water-ammonia mixture, and in proteins reveals that cation/ammonia solution can be used to approximate the coordination environment in proteins.

The subtle balance of weak supramolecular interactions: The hierarchy of halogen and hydrogen bonds in haloanilinium and halopyridinium salts.

PubMed

Raatikainen, Kari; Cametti, Massimo; Rissanen, Kari

2010-01-15

THE SERIES OF HALOANILINIUM AND HALOPYRIDINIUM SALTS: 4-IPhNH₃Cl (1), 4-IPhNH₃Br (5), 4-IPhNH₃H₂PO₄ (6), 4-ClPhNH₃H₂PO₄ (8), 3-IPyBnCl (9), 3-IPyHCl (10) and 3-IPyH-5NIPA (3-iodopyridinium 5-nitroisophthalate, 13), where hydrogen or/and halogen bonding represents the most relevant non-covalent interactions, has been prepared and characterized by single crystal X-ray diffraction. This series was further complemented by extracting some relevant crystal structures: 4-BrPhNH₃Cl (2, CCDC ref. code TAWRAL), 4-ClPhNH₃Cl (3, CURGOL), 4-FPhNH₃Cl (4, ANLCLA), 4-BrPhNH₃H₂PO₄, (7, UGISEI), 3-BrPyHCl, (11, CIHBAX) and 3-ClPyHCl, (12, VOQMUJ) from Cambridge Structural Database for sake of comparison. Based on the X-ray data it was possible to highlight the balance between non-covalent forces acting in these systems, where the relative strength of the halogen bonding C-X...A⁻ (X = I, Br or Cl) and the ratio between the halogen and hydrogen bonds [C-X...A⁻ : D-H...A⁻] varied across the series.

Undergraduate/Postgraduate Astronomy in Cambridge--A Student's Perspective.

ERIC Educational Resources Information Center

Williams, Robin

1991-01-01

Described is the undergraduate curriculum in physics and its relationship to astronomy at Cambridge University. Discussed are the astronomical research and research establishments at Cambridge. Personal views of a student on the postgraduate research being done at Cambridge are also included. (KR)

Multi-Decadal Oscillations of the Ocean Active Upper-Layer Heat Content

NASA Astrophysics Data System (ADS)

Byshev, Vladimir I.; Neiman, Victor G.; Anisimov, Mikhail V.; Gusev, Anatoly V.; Serykh, Ilya V.; Sidorova, Alexandra N.; Figurkin, Alexander L.; Anisimov, Ivan M.

2017-07-01

Spatial patterns in multi-decadal variability in upper ocean heat content for the last 60 years are examined using a numerical model developed at the Institute of Numerical Mathematics of Russia (INM Model) and sea water temperature-salinity data from the World Ocean Database (in: Levitus, NOAA Atlas NESDIS 66, U.S. Wash.: Gov. Printing Office, 2009). Both the model and the observational data show that the heat content of the Active Upper Layer (AUL) in particular regions of the Atlantic, Pacific and Southern oceans have experienced prominent simultaneous variations on multi-decadal (25-35 years) time scales. These variations are compared earlier revealed climatic alternations in the Northern Atlantic region during the last century (Byshev et al. in Doklady Earth Sci 438(2):887-892, 2011). We found that from the middle of 1970s to the end of 1990s the AUL heat content decreased in several oceanic regions, while the mean surface temperature increased on Northern Hemisphere continents according to IPCC (in: Stocker et al. Contribution of working group I to the fifth assessment report of the intergovernmental panel on climate change, Cambridge University Press, Cambridge, 2013). This means that the climate-forcing effect of the ocean-atmosphere interaction in certain energy-active areas determines not only local climatic processes, but also have an influence on global-scale climate phenomena. Here we show that specific regional features of the AUL thermal structure are in a good agreement with climatic conditions on the adjacent continents. Further, the ocean AUL in the five distinctive regions identified in our study have resumed warming in the first decade of this century. By analogy inference from previous climate scenarios, this may signal the onset of more continental climate over mainlands.

Global energy strategies: Looking over the horizon

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

NONE

1996-12-31

This document presents reports which were presented at the 1996 Cambridge Energy Research Associate`s (CERA) Executive Conference. Topics include: the political and economic outlook; CERA`s 1996 outlook; the energy company of the 21st century; oil market dynamics; natural gas business; generating strategies; growth opportunities in the oil industry; emerging oil and gas strategies; natural gas market; Asia Pacific energy; Latin America energy; California`s energy future; European gas and power opportunities; Russian and FSU energy. Individual reports were processed separately for the Department of Energy databases.

Diversity and Phylogenetic Structure of Two Complex Marine Microbial Communities

DTIC Science & Technology

2004-09-01

Science 190 and Engineering DOCTORAL DISSERTATION Diversity and Phylogenetic Structure of Two Complex Marine Microbial Communities by Vanja Klepac-Ceraj...Two Complex Marine Microbial Communities by Vanja Klepac-Ceraj Massachusetts Institute of Technology Cambridge, Massachusetts 02139 and Woods Hole...Phylogenetic Structure of Two Complex Marine Microbial Communities. Ph.D. Thesis. MIT/WHOI, 2004-11. Approved for publication; distribution unlimited

Perspectives on "Bakke": Equal Protection, Procedural Fairness, or Structural Justice?

ERIC Educational Resources Information Center

Tribe, Laurence H.

1979-01-01

The "Bakke" case is examined for what it has to say regarding first the area of equal protection, then the idea of procedural fairness as distinct from accuracy of result, and finally the notion of structural justice. Available from Harvard Law Review, Harvard Law Review Association, Gannett House, Cambridge, Massachusetts 02138; sc…

Surviving the Glut: The Management of Event Streams in Cyberphysical Systems

NASA Astrophysics Data System (ADS)

Buchmann, Alejandro

Alejandro Buchmann is Professor in the Department of Computer Science, Technische Universität Darmstadt, where he heads the Databases and Distributed Systems Group. He received his MS (1977) and PhD (1980) from the University of Texas at Austin. He was an Assistant/Associate Professor at the Institute for Applied Mathematics and Systems IIMAS/UNAM in Mexico, doing research on databases for CAD, geographic information systems, and objectoriented databases. At Computer Corporation of America (later Xerox Advanced Information Systems) in Cambridge, Mass., he worked in the areas of active databases and real-time databases, and at GTE Laboratories, Waltham, in the areas of distributed object systems and the integration of heterogeneous legacy systems. 1991 he returned to academia and joined T.U. Darmstadt. His current research interests are at the intersection of middleware, databases, eventbased distributed systems, ubiquitous computing, and very large distributed systems (P2P, WSN). Much of the current research is concerned with guaranteeing quality of service and reliability properties in these systems, for example, scalability, performance, transactional behaviour, consistency, and end-to-end security. Many research projects imply collaboration with industry and cover a broad spectrum of application domains. Further information can be found at http://www.dvs.tu-darmstadt.de

Unstable Behavior of Lasers and Other Optical Systems.

DTIC Science & Technology

1987-11-27

Isaacs, R.S. Gioggia, S.P. Adams, L.M. Narducci, L.A. Lugiato, Optical Instabilities, R.W. Boyd, M.G. Raymer , L.M. Narducci, Eds. (Cambridge...Instabilities, R.W. Boyd, M.G. Raymer , L.M. Narducci, Eds. (Cambridge University" Press, Cambridge, 1986), p. 34. "The Effect of Modulation in a Bistable System...Books "* " "OPTICAL INSTABILITIES", edited by R.W. Boyd, M.G. Raymer , and L.M. Narducci, Cambridge University Press, Cambridge, 1986. S P.-• 58

77 FR 64143 - Manufacturer of Controlled Substances; Notice of Registration; Cambridge Isotope Lab

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-18

...; Notice of Registration; Cambridge Isotope Lab By Notice dated June 18, 2012, and published in the Federal Register on June 26, 2012, 77 FR 38086, Cambridge Isotope Lab, 50 Frontage Road, Andover, Massachusetts....C. 823(a) and determined that the registration of Cambridge Isotope Lab to manufacture the listed...

Healthy travel and the socio-economic structure of car commuting in Cambridge, UK: a mixed-methods analysis.

PubMed

Goodman, Anna; Guell, Cornelia; Panter, Jenna; Jones, Natalia R; Ogilvie, David

2012-06-01

Car use is associated with substantial health and environmental costs but research in deprived populations indicates that car access may also promote psychosocial well-being within car-oriented environments. This mixed-method (quantitative and qualitative) study examined this issue in a more affluent setting, investigating the socio-economic structure of car commuting in Cambridge, UK. Our analyses involved integrating self-reported questionnaire data from 1142 participants in the Commuting and Health in Cambridge study (collected in 2009) and in-depth interviews with 50 participants (collected 2009-2010). Even in Britain's leading 'cycling city', cars were a key resource in bridging the gap between individuals' desires and their circumstances. This applied both to long-term life goals such as home ownership and to shorter-term challenges such as illness. Yet car commuting was also subject to constraints, with rush hour traffic pushing drivers to start work earlier and with restrictions on, or charges for, workplace parking pushing drivers towards multimodal journeys (e.g. driving to a 'park-and-ride' site then walking). These patterns of car commuting were socio-economically structured in several ways. First, the gradient of housing costs made living near Cambridge more expensive, affecting who could 'afford' to cycle and perhaps making cycling the more salient local marker of Bourdieu's class distinction. Nevertheless, cars were generally affordable in this relatively affluent, highly-educated population, reducing the barrier which distance posed to labour-force participation. Finally, having the option of starting work early required flexible hours, a form of job control which in Britain is more common among higher occupational classes. Following a social model of disability, we conclude that socio-economic advantage can make car-oriented environments less disabling via both greater affluence and greater job control, and in ways manifested across the full socio-economic range. This suggests the importance of combining individual-level 'healthy travel' interventions with measures aimed at creating travel environments in which all social groups can pursue healthy and satisfying lives. Copyright © 2012 Elsevier Ltd. All rights reserved.

Healthy travel and the socio-economic structure of car commuting in Cambridge, UK: A mixed-methods analysis

PubMed Central

Goodman, Anna; Guell, Cornelia; Panter, Jenna; Jones, Natalia R.; Ogilvie, David

2012-01-01

Car use is associated with substantial health and environmental costs but research in deprived populations indicates that car access may also promote psychosocial well-being within car-oriented environments. This mixed-method (quantitative and qualitative) study examined this issue in a more affluent setting, investigating the socio-economic structure of car commuting in Cambridge, UK. Our analyses involved integrating self-reported questionnaire data from 1142 participants in the Commuting and Health in Cambridge study (collected in 2009) and in-depth interviews with 50 participants (collected 2009–2010). Even in Britain's leading ‘cycling city’, cars were a key resource in bridging the gap between individuals' desires and their circumstances. This applied both to long-term life goals such as home ownership and to shorter-term challenges such as illness. Yet car commuting was also subject to constraints, with rush hour traffic pushing drivers to start work earlier and with restrictions on, or charges for, workplace parking pushing drivers towards multimodal journeys (e.g. driving to a ‘park-and-ride’ site then walking). These patterns of car commuting were socio-economically structured in several ways. First, the gradient of housing costs made living near Cambridge more expensive, affecting who could ‘afford’ to cycle and perhaps making cycling the more salient local marker of Bourdieu's class distinction. Nevertheless, cars were generally affordable in this relatively affluent, highly-educated population, reducing the barrier which distance posed to labour-force participation. Finally, having the option of starting work early required flexible hours, a form of job control which in Britain is more common among higher occupational classes. Following a social model of disability, we conclude that socio-economic advantage can make car-oriented environments less disabling via both greater affluence and greater job control, and in ways manifested across the full socio-economic range. This suggests the importance of combining individual-level ‘healthy travel’ interventions with measures aimed at creating travel environments in which all social groups can pursue healthy and satisfying lives. PMID:22465380

Yet another proof of Hawking and Ellis's Lemma 8.5.5

NASA Astrophysics Data System (ADS)

Krasnikov, S.

2014-11-01

The fact that the null generators of a future Cauchy horizon are past-complete was first proved by Hawking and Ellis (1973 The Large Scale Structure of Spacetime (Cambridge: Cambridge University Press)). Then, Budzyński, Kondracki and Królak outlined a proof free from the error found in the original one (2000 New properties of Cauchy and event horizons arXiv:gr-qc/0011033). Now, Minguzzi has published his version of the proof (2014 J. Math. Phys. 55 082503), patching a previously unnoticed hole in the preceding two. I am not aware of any flaws in that last proof, but it is quite difficult. In this note, I present a simpler one.

Time-resolved measurements of coherent structures in the turbulent boundary layer

NASA Astrophysics Data System (ADS)

LeHew, J. A.; Guala, M.; McKeon, B. J.

2013-04-01

Time-resolved particle image velocimetry was used to examine the structure and evolution of swirling coherent structure (SCS), one interpretation of which is a marker for a three-dimensional coherent vortex structure, in wall-parallel planes of a turbulent boundary layer with a large field of view, 4.3 δ × 2.2 δ. Measurements were taken at four different wall-normal locations ranging from y/ δ = 0.08-0.48 at a friction Reynolds number, Re τ = 410. The data set yielded statistically converged results over a larger field of view than typically observed in the literature. The method for identifying and tracking swirling coherent structure is discussed, and the resulting trajectories, convection velocities, and lifespan of these structures are analyzed at each wall-normal location. The ability of a model in which the entirety of an individual SCS travels at a single convection velocity, consistent with the attached eddy hypothesis of Townsend (The structure of turbulent shear flows. Cambridge University Press, Cambridge, 1976), to describe the data is investigated. A methodology for determining whether such structures are "attached" or "detached" from the wall is also proposed and used to measure the lifespan and convection velocity distributions of these different structures. SCS were found to persist for longer periods of time further from the wall, particularly those inferred to be "detached" from the wall, which could be tracked for longer than 5 eddy turnover times.

CH/π interactions in metal-porphyrin complexes with pyrrole and chelate rings as hydrogen acceptors.

PubMed

Medaković, Vesna B; Bogdanović, Goran A; Milčić, Miloš K; Janjić, Goran V; Zarić, Snežana D

2012-12-01

CH/π interactions in metal porphyrinato complexes were studied by analyzing data in crystal structures from the Cambridge Structural Database (CSD) and by quantum chemical calculations. The analysis of the data in the CSD shows that both five-membered pyrrole and six-membered chelate rings form CH/π interactions. The interactions occur more frequently with five-membered rings. The analysis of distances in crystal structures and calculated energies show stronger interactions with six-membered chelate rings, indicating that a larger number of interactions with five-membered rings are not the consequence of stronger interactions, but better accessibility of five-membered pyrrole rings. The calculated energies of the interactions with positions in six-membered rings are -2.09 to -2.83 kcal/mol, while the energies with five-membered rings are -2.05 to -2.26 kcal/mol. The results reveal that stronger interactions of six-membered rings are the consequence of stronger electrostatic interactions. Substituents on the porphyrin ring significantly strengthen the interactions. Substituents on the six-membered ring strengthen the interaction energy by about 20%. The results show that CH/π interactions play an important role in molecular recognition of metalloporphyrins. The significant influence of the substituents on interaction energies can be very important for the design of model systems in bioinorganic chemistry. Copyright © 2012 Elsevier Inc. All rights reserved.

Plasticity of Cl-Te-Cl Fragments. Synthesis, Single-Crystal X-ray, and NBO Study of (1-Thia-2-tellura-1-phenyl-4-chloro)cyclopentane 2,2,2-Trichloride.

PubMed

Sundberg, Markku R.; Laitalainen, Tarja; Bergman, Jan; Uggla, Rolf; Matikainen, Jorma; Kaltia, Seppo

1998-06-01

Tellurium tetrachloride and allylphenyl sulfide react to form (1-thia-2-tellura-1-phenyl-4-chloro)cyclopentane 2,2,2-trichloride. The crystal and molecular structure were determined by single-crystal X-ray techniques. The crystals belong to the monoclinic system, space group P2(1)/c (No. 14) with a = 6.020(3) Å, b = 11.46(1) Å, c = 20.156(2) Å, beta = 97.53(2) degrees, V = 1379(1) Å(3), and Z = 4. The structure was refined to the final R value of 0.036. The coordination around Te(IV) is distorted psi octahedral with three Cl atoms in the equatorial positions. The axial Te(1)-C(1) bond opposite to the lone pair of electrons at the Te(IV) atom completes the coordination polyhedron. The intramolecular Te-S distance is 2.903(3) Å. Symmetric and asymmetric deformation modes were established to describe the plasticity of the Cl-Te-Cl fragments extracted from the Cambridge Structural Database. The hypervalency of Te(IV) manifests itself as plasticity in the equatorial plane of the coordination sphere. The NBO calculations show that all of the equatorial Te-Cl bonds are highly polarized and the electrons reside mainly on the Cl atoms.

Freyinae, a major new subfamily of Neotropical jumping spiders (Araneae: Salticidae).

PubMed

Edwards, G B

2015-11-02

Freyinae, new subfamily, is described for a group of genera of Neotropical jumping spiders that can be distinguished from other non-ant mimic salticoid Neotropical salticids by having the following three morphological features: a slightly more elongate carapace, a distinctive prolateral tibial macrosetae arrangement (medially placed subdistal and subproximal macrosetae, with a subdorsal medial macroseta in some males), and an unusual dorsoventrally thick tegulum basal division (although one or two of these features are sometimes lost). It includes 20 genera previously considered valid, of which 19 are retained: Akela Peckham & Peckham, 1896, Aphirape C.L. Koch, 1850, Asaracus C.L. Koch, 1846, Capidava Simon, 1902, Chira Peckham & Peckham, 1896, Edilemma Ruiz & Brescovit, 2006, Eustiromastix Simon, 1902, Freya C.L. Koch, 1850, Frigga C.L. Koch, 1850, Kalcerrytus Galiano, 2000, Nycerella Galiano, 1982, Onofre Ruiz & Brescovit, 2007, Pachomius Peckham & Peckham, 1896, Phiale C.L. Koch, 1846, Rishaschia Makhan, 2006, Sumampattus Galiano, 1983, Trydarssus Galiano, 1995, Tullgrenella Mello‑Leitão, 1941, and Wedoquella Galiano, 1984. Romitia Caporiacco, 1947 (and its synonym Uspachus Galiano, 1995) is synonymized with Pachomius, new synonymy. New genera described in the subfamily are: Drizztius, Leptofreya, Megafreya, Philira, Tarkas, Triggella, and Xanthofreya. The following nomenclatorial changes are made: New synonyms: Freya demarcata Chamberlin & Ivie, 1936 = Freya (sub Cyrene) albosignata (F.O.P.-Cambridge, 1901); Freya (sub Cyrene) grisea (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) infuscata (F.O.P.-Cambridge, 1901); Freya (sub Cyrene) emarginata (F.O.P.-Cambridge, 1901) and Nycerella (sub Heraclea) sanguinea paradoxa (Peckham & Peckham, 1896) = Nycerella (sub Heraclea) sanguinea (Peckham & Peckham, 1896); Pachomius (sub Phiale) maculosus (Chickering, 1946) = Phiale (sub Cyrene) bilobata (F.O.P.-Cambridge, 1901); Phiale (sub Cyrene) mediocava (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) maculatipes (F.O.P.-Cambridge, 1901); Phiale (sub Cyrene) simplicicava (F.O.P.-Cambridge, 1901) = Freya (sub Cyrene) bifurcata (F.O.P.-Cambridge, 1901). New combinations: Capidava rufithorax Simon, 1902 = Drizztius rufithorax; Freya frontalis Banks, 1929 = Eustiromastix frontalis; Chira (sub Attus) spinipes (Taczanowski, 1872) = Eustiromastix spinipes; Freya (sub Euophrys) ambigua (C.L. Koch, 1846) = Leptofreya ambigua; Freya (sub Cyrene) bifurcata (F.O.P.-Cambridge, 1901) = Leptofreya bifurcata; Freya (sub Cyrene) laticava (F.O.P.-Cambridge, 1901) = Leptofreya laticava; Freya (sub Cyrene) longispina (F.O.P.-Cambridge, 1901) = Leptofreya longispina; Phiale (sub Cyrene) bilobata (F.O.P.-Cambridge, 1901) = Pachomius bilo-batus; Phiale (sub Cyrene) hieroglyphica (F.O.P.-Cambridge, 1901) = Pachomius hieroglyphicus; Phiale (sub Cyrene) niveoguttata (F.O.P.-Cambridge, 1901) = Pachomius niveoguttatus; Romitia (sub Euophrys) albipalpis (Taczanowski, 1878) = Pachomius albipalpis; Romitia (sub Euophrys) andina (Taczanowski, 1878) = Pachomius andinus; Romitia (sub Uspachus) bahiensis (Galiano, 1995) = Pachomius bahiensis; Romitia (sub Uspachus) columbiana (Galiano, 1995) = Pachomius columbianus; Romitia (sub Uspachus) juquiaensis (Galiano, 1995) = Pachomius juquiaensis; Romitia (sub Phiale) ministerialis (C.L. Koch, 1846) = Pachomius ministerialis; Romitia (sub Uspachus) misionensis (Galiano, 1995) = Pachomius misionensis; Romitia nigra Caporiacco, 1947 = Pachomius nigrus; Romitia (sub Uspachus) patellaris (Galiano, 1995) = Pachomius patellaris; Chira (sub Diagondas) micans (Simon, 1902) = Philira micans; Chira superba Caporiacco, 1947 = Philira superba; Freya (sub Cyrene) maculatipes (F.O.P.-Cambridge, 1901) = Tarkas maculatipes; Freya (sub Cyrene) bifida (F.O.P.-Cambridge, 1901) = Triggella bifida; Freya infuscata (F.O.P.-Cambridge, 1901) = Triggella infuscata; Freya (sub Cyrene) minuta (F.O.P.-Cambridge, 1901) = Triggella minuta; Freya (sub Cyrene) albosignata (F.O.P.-Cambridge, 1901) = Xanthofreya albosignata; Freya arraijanica Chickering, 1946 = Xanthofreya arraijanica; Phiale (sub Cyrene) bicuspidata (F.O.P.-Cambridge, 1901) = Xantho-freya bicuspidata; Freya chionopogon Simon, 1902 = Xanthofreya chionopogon; Freya (sub Heraclea) rustica (Peckham & Peckham, 1896) = Xanthofreya rustica. Combinations restored: Phiale (sub Pachomius) flavescens (Peckham & Peckham, 1896) = Pachomius flavescens; Phiale (sub Pachomius) similis (Peckham & Peckham, 1896) = Pachomius similis. Invalid name: Freya dyali Roewer 1951 is an invalid replacement name for Euophrys trifasciata "Dyal 1935", which was a redescription of Euophrys trifasciata C.L. Koch, 1846, not a homonym. New species: Drizztius geminensis. First female descriptions and transfers of mismatched females: First descriptions for Asaracus megacephalus C.L. Koch, 1846, Capidava biuncata Simon, 1902, and Phiale formosa (Banks, 1909); the true female of Eustiromastix spinipes is described, and its mismatched female is identified as the female of Eustiromastix falcatus Galiano, 1981; the mismatched female of Freya (sub Cyrene) prominens (F.O.P.-Cambridge, 1901) is identified as the female of Xanthofreya rustica; the misidentified female of X. rustica is identified as the female of Leptofreya bifurcata. Lectotypes: designated for Cyrene bifida F.O.P.-Cambridge, 1901 and Cyrene formosa Banks, 1909. New synapomorphy: a constricted proximal end of the cymbium of the male palp is an apparent new synapomorphy for Salticoida.

Multi-temperature study of potassium uridine-5'-monophosphate: electron density distribution and anharmonic motion modelling.

PubMed

Jarzembska, Katarzyna N; Řlepokura, Katarzyna; Kamiński, Radosław; Gutmann, Matthias J; Dominiak, Paulina M; Woźniak, Krzysztof

2017-08-01

Uridine, a nucleoside formed of a uracil fragment attached to a ribose ring via a β-N1-glycosidic bond, is one of the four basic components of ribonucleic acid. Here a new anhydrous structure and experimental charge density distribution analysis of a uridine-5'-monophosphate potassium salt, K(UMPH), is reported. The studied case constitutes the very first structure of a 5'-nucleotide potassium salt according to the Cambridge Structural Database. The excellent crystal quality allowed the collection of charge density data at various temperatures, i.e. 10, 100, 200 and 300 K on one single crystal. Crystal structure and charge density data were analysed thoroughly in the context of related literature-reported examples. Detailed analysis of the charge density distribution revealed elevated anharmonic motion of part of the uracil ring moiety relatively weakly interacting with the neighbouring species. The effect was manifested by alternate positive and negative residual density patterns observed for these atoms, which `disappear' at low temperature. It also occurred that the potassium cation, quite uniformly coordinated by seven O atoms from all molecular fragments of the UMPH - anion, including the O atom from the ribofuranose ring, can be treated as spherical in the charge density model which was supported by theoretical calculations. Apart from the predominant electrostatic interactions, four relatively strong hydrogen bond types further support the stability of the crystal structure. This results in a compact and quite uniform structure (in all directions) of the studied crystal, as opposed to similar cases with layered architecture reported in the literature.

First-line antituberculosis drug, pyrazinamide, its pharmaceutically relevant cocrystals and a salt.

PubMed

Sarmah, Kashyap Kumar; Rajbongshi, Trishna; Bhowmick, Sourav; Thakuria, Ranjit

2017-10-01

A few pyrazinamide (Pyz) cocrystals involving hydroxybenzoic/cinnamic acid derivatives [2,4-dihydroxybenzoic acid (24DHBA); 2,6-dihydroxybenzoic acid (26DHBA); 3,5-dihydroxybenzoic acid (35DHBA) and nutraceutical molecule ferulic acid (FRA)] and the first example of a molecular salt with p-toluenesulfonic acid (pTSA) have been prepared and characterized using various solid-state techniques. A high-temperature cocrystal polymorph of Pyz·FRA has been characterized from the endothermic peaks observed using differential scanning calorimetry. The presence of substituent groups carrying hydrogen bond donors or acceptors and their influence on supramolecular synthon formation has been investigated using a Cambridge Structural Database search. Equilibrium solubility of all the binary complexes of Pyz follows the order of their coformer solubility, i.e. Pyz + ·pTSA - > Pyz·35DHBA > Pyz > Pyz·26DHBA > Pyz·24DHBA > Pyz·FRA. A twofold enhancement in solubility of Pyz + ·pTSA - molecular salt compared with the parent drug suggests a potential drug formulation for the treatment of tuberculosis.

Parametrization of a force field for metals complexed to biomacromolecules: applications to Fe(II), Cu(II) and Pb(II)

NASA Astrophysics Data System (ADS)

David, Laurent; Amara, Patricia; Field, Martin J.; Major, François

2002-08-01

Although techniques for the simulation of biomolecules, such as proteins and RNAs, have greatly advanced in the last decade, modeling complexes of biomolecules with metal ions remains problematic. Precise calculations can be done with quantum mechanical methods but these are prohibitive for systems the size of macromolecules. More qualitative modeling can be done with molecular mechanical potentials but the parametrization of force fields for metals is often difficult, particularly if the bonding between the metal and the groups in its coordination shell has significant covalent character. In this paper we present a method for deriving bond and bond-angle parameters for metal complexes from experimental bond and bond-angle distributions obtained from the Cambridge Structural Database. In conjunction with this method, we also introduce a non-standard energy term of gaussian form that allows us to obtain a stable description of the coordination about a metal center during a simulation. The method was evaluated on Fe(II)-porphyrin complexes, on simple Cu(II) ion complexes and a number of complexes of the Pb(II) ion.

Structural and electronic snapshots during the transition from a Cu(II) to Cu(I) metal center of a lytic polysaccharide monooxygenase by X-ray photoreduction.

PubMed

Gudmundsson, Mikael; Kim, Seonah; Wu, Miao; Ishida, Takuya; Momeni, Majid Hadadd; Vaaje-Kolstad, Gustav; Lundberg, Daniel; Royant, Antoine; Ståhlberg, Jerry; Eijsink, Vincent G H; Beckham, Gregg T; Sandgren, Mats

2014-07-04

Lytic polysaccharide monooxygenases (LPMOs) are a recently discovered class of enzymes that employ a copper-mediated, oxidative mechanism to cleave glycosidic bonds. The LPMO catalytic mechanism likely requires that molecular oxygen first binds to Cu(I), but the oxidation state in many reported LPMO structures is ambiguous, and the changes in the LPMO active site required to accommodate both oxidation states of copper have not been fully elucidated. Here, a diffraction data collection strategy minimizing the deposited x-ray dose was used to solve the crystal structure of a chitin-specific LPMO from Enterococcus faecalis (EfaCBM33A) in the Cu(II)-bound form. Subsequently, the crystalline protein was photoreduced in the x-ray beam, which revealed structural changes associated with the conversion from the initial Cu(II)-oxidized form with two coordinated water molecules, which adopts a trigonal bipyramidal geometry, to a reduced Cu(I) form in a T-shaped geometry with no coordinated water molecules. A comprehensive survey of Cu(II) and Cu(I) structures in the Cambridge Structural Database unambiguously shows that the geometries observed in the least and most reduced structures reflect binding of Cu(II) and Cu(I), respectively. Quantum mechanical calculations of the oxidized and reduced active sites reveal little change in the electronic structure of the active site measured by the active site partial charges. Together with a previous theoretical investigation of a fungal LPMO, this suggests significant functional plasticity in LPMO active sites. Overall, this study provides molecular snapshots along the reduction process to activate the LPMO catalytic machinery and provides a general method for solving LPMO structures in both copper oxidation states. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

Spontaneous Discovery and Use of Categorical Structures

DTIC Science & Technology

1992-02-15

must be defined by a set of necessary and sufficient features, an assumption that has been strongly criticized in recent years (e.g., Wittgenstein ...J.: Lawrence Erlbaum Associates. Smith, E. E., & Medin, D. L. (1981). Categories and concepts. Cambridge, MA: Harvard University Press. Wittgenstein

Bent CNN bond of diazo compounds, RR'(Cdbnd N+dbnd N-)

NASA Astrophysics Data System (ADS)

Akita, Motoko; Takahashi, Mai; Kobayashi, Keiji; Hayashi, Naoto; Tukada, Hideyuki

2013-02-01

The reaction of ninhydrin with benzophenone hydrazone afforded 2-diazo-3-diphenylmethylenehydrazono-1-indanone 1 and 2-diazo-1,3-bis(diphenylmethylenehydrazono)indan 2. X-ray crystal structure analyses of these products showed that the diazo functional group Cdbnd N+dbnd N- of 1 is bent by 172.9°, while that of 2 has a linear geometry. The crystal structure data of diazo compounds have been retrieved from the Cambridge Structural Database (CSD), which hit 177 entries to indicate that the angle of 172.9° in 1 lies in one of the most bent structures. The CSD search also indicated that diazo compounds consisting of a distorted diazo carbon tend to bend the Cdbnd N+dbnd N- bond. On the basis of DFT calculations (B3LYP/6-311++G(d,p)) of model compounds, it was revealed that the bending of the CNN bond is principally induced by steric factors and that the neighboring carbonyl group also plays a role in bending toward the carbonyl side owing to an electrostatic attractive interaction. The potential surface along the path of Cdbnd N+dbnd N- bending in 2-diazopropane shows a significantly shallow profile with only 4 kcal/mol needed to bend the Cdbnd N+dbnd N- bond from 180° to 160°. Thus, the bending of the diazo group in 1 is reasonable as it is provided with all of the factors for facile bending disclosed in this investigation.

Recognition of a novel type X═N-Hal···Hal (X = C, S, P; Hal = F, Cl, Br, I) halogen bonding.

PubMed

Gushchin, Pavel V; Kuznetsov, Maxim L; Haukka, Matti; Kukushkin, Vadim Yu

2013-04-04

The chlorination of the eight-membered platinum(II) chelates [PtCl2{NH═C(NR2)N(Ph)C(═NH)N(Ph)C(NR2)═NH}] (R = Me (1); R2 = (CH2)5 (2)) with uncomplexed imino group with Cl2 gives complexes bearing the ═N-Cl moiety [PtCl4{NH═C(NR2)N(Ph)C(═NCl)N(Ph)C(NR2)═NH}] (R = Me (3); R2 = (CH2)5 (4)). X-ray study for 3 revealed a novel type intermolecular halogen bonding ═N-Cl···Cl(-), formed between the Cl atom of the chlorinated imine and the chloride bound to the platinum(IV) center. The processing relevant structural data retrieved from the Cambridge Structural Database (CSDB) shows that this type of halogen bonding is realized in 18 more molecular species having X═N-Hal moieties (X = C, P, S, V, W; Hal = Cl, Br, I), but this weak ═N-Hal···Hal(-) bonding was totally neglected in the previous works. The presence of the halogen bonding in 3 was confirmed by theoretical calculations at the density functional theory (DFT, M06-2X) level, and its nature was analyzed.

Does the choice of the crystal structure influence the results of the periodic DFT calculations? A case of glycine alpha polymorph GIPAW NMR parameters computations.

PubMed

Szeleszczuk, Łukasz; Pisklak, Dariusz Maciej; Zielińska-Pisklak, Monika

2018-05-30

Glycine is a common amino acid with relatively complex chemistry in solid state. Although several polymorphs (α, β, δ, γ, ε) of crystalline glycine are known, for NMR spectroscopy the most important is a polymorph, which is used as a standard for calibration of spectrometer performance and therefore it is intensively studied by both experimental methods and theoretical computation. The great scientific interest in a glycine results in a large number of crystallographic information files (CIFs) deposited in Cambridge Structural Database (CSD). The aim of this study was to evaluate the influence of the chosen crystal structure of α glycine obtained in different crystallographic experimental conditions (temperature, pressure and source of radiation of α glycine) on the results of periodic DFT calculation. For this purpose the total of 136 GIPAW calculations of α glycine NMR parameters were performed, preceded by the four approaches ("SP", "only H", "full", "full+cell") of structure preparation. The analysis of the results of those computations performed on the representative group of 34 structures obtained at various experimental conditions revealed that though the structures were generally characterized by good accuracy (R < 0.05 for most of them) the results of the periodic DFT calculations performed using the unoptimized structures differed significantly. The values of the standard deviations of the studied NMR parameters were in most cases decreasing with the number of optimized parameters. The most accurate results (of the calculations) were in most cases obtained using the structures with solely hydrogen atoms positions optimized. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Amide-N-oxide heterosynthon and amide dimer homosynthon in cocrystals of carboxamide drugs and pyridine N-oxides.

PubMed

Babu, N Jagadeesh; Reddy, L Sreenivas; Nangia, Ashwini

2007-01-01

The carboxamide-pyridine N-oxide heterosynthon is sustained by syn(amide)N-H...O-(oxide) hydrogen bond and auxiliary (N-oxide)C-H...O(amide) interaction (Reddy, L. S.; Babu, N. J.; Nangia, A. Chem. Commun. 2006, 1369). We evaluate the scope and utility of this heterosynthon in amide-containing molecules and drugs (active pharmaceutical ingredients, APIs) with pyridine N-oxide cocrystal former molecules (CCFs). Out of 10 cocrystals in this study and 7 complexes from previous work, amide-N-oxide heterosynthon is present in 12 structures and amide dimer homosynthon occurs in 5 structures. The amide dimer is favored over amide-N-oxide synthon in cocrystals when there is competition from another H-bonding functional group, e.g., 4-hydroxybenzamide, or because of steric factors, as in carbamazepine API. The molecular organization in carbamazepine.quinoxaline N,N'-dioxide 1:1 cocrystal structure is directed by amide homodimer and anti(amide)N-H...O-(oxide) hydrogen bond. Its X-ray crystal structure matches with the third lowest energy frame calculated in Polymorph Predictor (Cerius(2), COMPASS force field). Apart from generating new and diverse supramolecular structures, hydration is controlled in one substance. 4-Picoline N-oxide deliquesces within a day, but its cocrystal with barbital does not absorb moisture at 50% RH and 30 degrees C up to four weeks. Amide-N-oxide heterosynthon has potential utility in both amide and N-oxide type drug molecules with complementary CCFs. Its occurrence probability in the Cambridge Structural Database is 87% among 27 structures without competing acceptors and 78% in 41 structures containing OH, NH, H(2)O functional groups.

Standard atomic volumes in double-stranded DNA and packing in protein–DNA interfaces

PubMed Central

Nadassy, Katalin; Tomás-Oliveira, Isabel; Alberts, Ian; Janin, Joël; Wodak, Shoshana J.

2001-01-01

Standard volumes for atoms in double-stranded B-DNA are derived using high resolution crystal structures from the Nucleic Acid Database (NDB) and compared with corresponding values derived from crystal structures of small organic compounds in the Cambridge Structural Database (CSD). Two different methods are used to compute these volumes: the classical Voronoi method, which does not depend on the size of atoms, and the related Radical Planes method which does. Results show that atomic groups buried in the interior of double-stranded DNA are, on average, more tightly packed than in related small molecules in the CSD. The packing efficiency of DNA atoms at the interfaces of 25 high resolution protein–DNA complexes is determined by computing the ratios between the volumes of interfacial DNA atoms and the corresponding standard volumes. These ratios are found to be close to unity, indicating that the DNA atoms at protein–DNA interfaces are as closely packed as in crystals of B-DNA. Analogous volume ratios, computed for buried protein atoms, are also near unity, confirming our earlier conclusions that the packing efficiency of these atoms is similar to that in the protein interior. In addition, we examine the number, volume and solvent occupation of cavities located at the protein–DNA interfaces and compared them with those in the protein interior. Cavities are found to be ubiquitous in the interfaces as well as inside the protein moieties. The frequency of solvent occupation of cavities is however higher in the interfaces, indicating that those are more hydrated than protein interiors. Lastly, we compare our results with those obtained using two different measures of shape complementarity of the analysed interfaces, and find that the correlation between our volume ratios and these measures, as well as between the measures themselves, is weak. Our results indicate that a tightly packed environment made up of DNA, protein and solvent atoms plays a significant role in protein–DNA recognition. PMID:11504874

The Structure of Analogical Models in Science.

DTIC Science & Technology

1980-07-01

standard 69I edition of the complete psychological words of Sigmund Freud , Vol. XVII. London, The Hogarth Press Ltd. and the Isltitute of Psycho-Analysis...Intelligence. Cambridge, Ma.: MIT, 1977, 299-304. Freud , S. On transformations of instinct as exemplified in anal eroticism. In J. Strachey (Ed.), The

Proceedings of the Workshop on Transportation/Urban Form Interactions held at Cambridge, MA. on August 14-15, 1978

DOT National Transportation Integrated Search

1979-06-01

Contents: A form of utility function for the UMOT model; An analysis of transportation/land use interactions; Toward a methodology to shape urban structure; Approaches for improving urban travel forecasts; Quasi-dynamic urban location models with end...

New Graph Models and Algorithms for Detecting Salient Structures from Cluttered Images

DTIC Science & Technology

2010-02-24

Development of graph models and algorithms to detect boundaries that show certain levels of symmetry, an important geometric property of many...Bookstein. Morphometric tools for landmark data. Cambridge University Press, 1991. [8] F. L. Bookstein. Principal warps: Thin-plate splines and the

Data-Driven High-Throughput Prediction of the 3D Structure of Small Molecules: Review and Progress

PubMed Central

Andronico, Alessio; Randall, Arlo; Benz, Ryan W.; Baldi, Pierre

2011-01-01

Accurate prediction of the 3D structure of small molecules is essential in order to understand their physical, chemical, and biological properties including how they interact with other molecules. Here we survey the field of high-throughput methods for 3D structure prediction and set up new target specifications for the next generation of methods. We then introduce COSMOS, a novel data-driven prediction method that utilizes libraries of fragment and torsion angle parameters. We illustrate COSMOS using parameters extracted from the Cambridge Structural Database (CSD) by analyzing their distribution and then evaluating the system’s performance in terms of speed, coverage, and accuracy. Results show that COSMOS represents a significant improvement when compared to the state-of-the-art, particularly in terms of coverage of complex molecular structures, including metal-organics. COSMOS can predict structures for 96.4% of the molecules in the CSD [99.6% organic, 94.6% metal-organic] whereas the widely used commercial method CORINA predicts structures for 68.5% [98.5% organic, 51.6% metal-organic]. On the common subset of molecules predicted by both methods COSMOS makes predictions with an average speed per molecule of 0.15s [0.10s organic, 0.21s metal-organic], and an average RMSD of 1.57Å [1.26Å organic, 1.90Å metal-organic], and CORINA makes predictions with an average speed per molecule of 0.13s [0.18s organic, 0.08s metal-organic], and an average RMSD of 1.60Å [1.13Å organic, 2.11Å metal-organic]. COSMOS is available through the ChemDB chemoinformatics web portal at: http://cdb.ics.uci.edu/. PMID:21417267

Findings from the Harvard Medical School Cambridge Integrated Clerkship, a Year-Long Longitudinal Psychiatry Experience.

PubMed

Cheng, Elisa; Hirsh, David; Gaufberg, Elizabeth; Griswold, Todd; Wesley Boyd, J

2018-06-01

The Harvard Medical School Cambridge Integrated Clerkship is a longitudinal integrated clerkship that has provided an alternative clinical model for medical education in psychiatry since its inception in 2004. This study was undertaken in an effort to better understand the student experience of the Cambridge Integrated Clerkship and how it may have impacted students' perceptions of and interest in psychiatry, as well as performance. Qualitative surveys were sent via e-mail to the first 11 student cohorts who had completed the Cambridge Integrated Clerkship (from 2004 to 2014) and for whom we had e-mail addresses (N = 100), and the free-text responses were coded thematically. All available standardized scoring data and residency match data for Cambridge Integrated Clerkship graduates were obtained. From 2006 to 2014, 12 out of 73 Cambridge Integrated Clerkship students who entered the match chose a psychiatry residency (16.4%), four times more than students in traditional clerkships at Harvard Medical School (3.8% of 1355 students) or the national average (4.1% of 146,066 US applicants). Thirty of the 100 surveyed Cambridge Integrated Clerkship graduates (30%) responded to the qualitative survey with free-text remarks on a number of themes. Cambridge Integrated Clerkship students compared positively to their classmates in terms of standardized test performance. Their fourfold higher match rate into psychiatry compared to other students raises intriguing questions as to what role a longitudinal clerkship might have played in developing interest in psychiatry as a career.

Revision Planned for the Cambridge Latin Course.

ERIC Educational Resources Information Center

Sebesta, Judith Lynn

1980-01-01

Summarizes a discussion on the revision of the Cambridge Latin Course (CLC) held during the 1980 ACL Institute at the University of New Hampshire by CLC users and Cambridge University Press representatives. Emphasizes suggestions by users on grammar instruction strategies better suited to American students' needs. (MES)

Teachers Learning: Professional Development and Education. Cambridge Education Research Series

ERIC Educational Resources Information Center

McLaughlin, Colleen, Ed.

2012-01-01

"Teachers Learning: Professional Development and Education" is part of The Cambridge Education Research series, edited by senior colleagues at the University of Cambridge Faculty of Education, which has a longstanding tradition of involvement in high quality, innovative teacher education and continuing professional development.…

A Solution Method for Large Deformation Contact Problems.

DTIC Science & Technology

1984-10-01

15] Desai, C.S., Zaman, M.M., Lightner , J.G., and Siriwardane, H.J., "Thin Element for Interfaces and Joints," Int. J. Anal. and Num. Meth. in...Urbana, IL 61801 SMCCR-SPS-IL 1 Massachusetts Institute of Technology Aeroelastic and Structures Research Laboratory ATTN: Dr. E. A. Witmer Cambridge

Optimal Regulation of Structural Systems with Uncertain Parameters.

DTIC Science & Technology

1981-02-02

been addressed, in part, by Statistical Energy Analysis . Moti- vated by a concern with high frequency vibration and acoustical- structural...Parameter Systems," AFOSR-TR-79-0753 (May, 1979). 25. R. H. Lyon, Statistical Energy Analysis of Dynamical Systems: Theory and Applications, (M.I.T...Press, Cambridge, Mass., 1975). 26. E. E. Ungar, " Statistical Energy Analysis of Vibrating Systems," Trans. ASME, J. Eng. Ind. 89, 626 (1967). 139 27

Ottoman Turkish in the High School Curriculum: Current Language Planning Discussions in Turkey

ERIC Educational Resources Information Center

Yazan, Bedrettin; Üzüm, Melike

2017-01-01

This paper explores the recent policy decision about the teaching of Ottoman Turkish at high schools in Turkey and unpacks its historical, political, and social undercurrents. It theoretically rests upon Spolsky's [2004. "Language policy". Cambridge: Cambridge University Press, 2009. "Language management." Cambridge: Cambridge…

76 FR 77257 - Manufacturer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-12

... 18, 2011, 76 FR 51400, Cambridge Isotope Lab, 50 Frontage Road, Andover, Massachusetts 01810, made... determined that the registration of Cambridge Isotope Lab to manufacture the listed basic class of controlled substance is consistent with the public interest at this time. DEA has investigated Cambridge Isotope Lab to...

Analysis of zinc binding sites in protein crystal structures.

PubMed

Alberts, I L; Nadassy, K; Wodak, S J

1998-08-01

The geometrical properties of zinc binding sites in a dataset of high quality protein crystal structures deposited in the Protein Data Bank have been examined to identify important differences between zinc sites that are directly involved in catalysis and those that play a structural role. Coordination angles in the zinc primary coordination sphere are compared with ideal values for each coordination geometry, and zinc coordination distances are compared with those in small zinc complexes from the Cambridge Structural Database as a guide of expected trends. We find that distances and angles in the primary coordination sphere are in general close to the expected (or ideal) values. Deviations occur primarily for oxygen coordinating atoms and are found to be mainly due to H-bonding of the oxygen coordinating ligand to protein residues, bidentate binding arrangements, and multi-zinc sites. We find that H-bonding of oxygen containing residues (or water) to zinc bound histidines is almost universal in our dataset and defines the elec-His-Zn motif. Analysis of the stereochemistry shows that carboxyl elec-His-Zn motifs are geometrically rigid, while water elec-His-Zn motifs show the most geometrical variation. As catalytic motifs have a higher proportion of carboxyl elec atoms than structural motifs, they provide a more rigid framework for zinc binding. This is understood biologically, as a small distortion in the zinc position in an enzyme can have serious consequences on the enzymatic reaction. We also analyze the sequence pattern of the zinc ligands and residues that provide elecs, and identify conserved hydrophobic residues in the endopeptidases that also appear to contribute to stabilizing the catalytic zinc site. A zinc binding template in protein crystal structures is derived from these observations.

Five-coordinate Co(II) complexes with nitrilotriacetic acid: Crystal structures of Ca[Co(Nta)X] . nH{sub 2}O (X{sup -} = Cl, Br, or NCS)

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

Polyakova, I. N.; Poznyak, A. L.; Sergienko, V. S.

2006-07-15

The synthesis and X-ray diffraction study of three Ca[Co(Nta)X] . nH{sub 2}O complexes [X{sup -} = Cl, n = 2.3 (I); X{sup -} = Br, n = 2 (II); and X{sup -} = NCS, n = 2 (III)] are performed. The main structural units of crystals I-III are the [CoX(Nta)]{sup 2-} anionic complexes and hydrated Ca{sup 2+} cations. The anionic complexes have similar structures. The coordination of the Co{sup 2+} atom in the shape of a trigonal bipyramid is formed by N + 3O atoms of the Nta{sup 3-} ligand and the X{sup -} anion in the trans position withmore » respect to N. In structures I-III, the Co-O and Co-N bond lengths lie in the ranges 1.998-2.032 and 2.186-2.201 A, respectively. The Co-X bond lengths are 2.294 (I), 2.436 and 2.445 (II), and 1.982 A (III). The environments of the Ca{sup 2+} cations include oxygen atoms of one or two water molecules and six or seven O(Nta) atoms with the coordination number of 9 in I or 8 in II and III. The Ca-O(Nta) bonds form a three-dimensional framework in I or layers in II and III. Water molecules are involved in the hydrogen bonds O(w)-H...O(Nta), O(w)-H...X, and O(w)-H...O(w). Structural data for crystals I-III are deposited with the Cambridge Structural Database (CCDC nos. 287 814-287 816)« less

Annular tautomerism: experimental observations and quantum mechanics calculations.

PubMed

Cruz-Cabeza, Aurora J; Schreyer, Adrian; Pitt, William R

2010-06-01

The use of MP2 level quantum mechanical (QM) calculations on isolated heteroaromatic ring systems for the prediction of the tautomeric propensities of whole molecules in a crystalline environment was examined. A Polarisable Continuum Model was used in the calculations to account for environment effects on the tautomeric relative stabilities. The calculated relative energies of tautomers were compared to relative abundances within the Cambridge Structural Database (CSD) and the Protein Data Bank (PDB). The work was focussed on 84 annular tautomeric forms of 34 common ring systems. Good agreement was found between the calculations and the experimental data even if the quantity of these data was limited in many cases. The QM results were compared to those produced by much faster semiempirical calculations. In a search for other sources of the useful experimental data, the relative numbers of known compounds in which prototropic positions were often substituted by heavy atoms were also analysed. A scheme which groups all annular tautomeric transformations into 10 classes was developed. The scheme was designed to encompass a comprehensive set of known and theoretically possible tautomeric ring systems generated as part of a previous study. General trends across analogous ring systems were detected as a result. The calculations and statistics collected on crystallographic data as well as the general trends observed should be useful for the better modelling of annular tautomerism in the applications such as computer-aided drug design, small molecule crystal structure prediction, the naming of compounds and the interpretation of protein-small molecule crystal structures.

Characterising non-covalent interactions with the Cambridge Structural Database.

PubMed

Lommerse, J P; Taylor, R

1997-02-01

This review describes how the CSD can be used to study non-covalent interactions. Several different types of information may be obtained. First, the relative frequencies of various interactions can be studied; for example, we have shown that the terminal oxygen atoms of phosphate groups accept hydrogen bonds far more often than the linkage oxygens. Secondly, information can be obtained about the geometries of nonbonded contacts; for example, hydrogen bonds to P-O groups rarely form along the extension of the P-O bond, whereas short contacts between oxygen and carbon-bound iodine show a strong preference for linear C-I ... O angles. Thirdly, the CSD can be searched for novel interactions which may be exploited in inhibitor design; for example, the I ... O contacts just mentioned, and N-H ... pi hydrogen bonds. Finally, the CSD can suggest synthetic targets for medicinal chemistry; for example, molecules containing delocalised electron deficient groups such as trimethylammonium, pyridinium, thaizolium and dinitrophenyl have a good chance of binding to an active-site tryptophan. Although the CSD contains small-molecule crystal structures, not protein-ligand complexes, there is considerable evidence that the contacts seen in the two types of structures are similar. We have illustrated this a number of times in the present review and additional evidence has been given previously by Klebe. The major advantages of the CSD are its size, diversity and experimental accuracy. For these reasons, it is a useful tool for modellers engaged in rational inhibitor design.

Annular tautomerism: experimental observations and quantum mechanics calculations

NASA Astrophysics Data System (ADS)

Cruz-Cabeza, Aurora J.; Schreyer, Adrian; Pitt, William R.

2010-06-01

The use of MP2 level quantum mechanical (QM) calculations on isolated heteroaromatic ring systems for the prediction of the tautomeric propensities of whole molecules in a crystalline environment was examined. A Polarisable Continuum Model was used in the calculations to account for environment effects on the tautomeric relative stabilities. The calculated relative energies of tautomers were compared to relative abundances within the Cambridge Structural Database (CSD) and the Protein Data Bank (PDB). The work was focussed on 84 annular tautomeric forms of 34 common ring systems. Good agreement was found between the calculations and the experimental data even if the quantity of these data was limited in many cases. The QM results were compared to those produced by much faster semiempirical calculations. In a search for other sources of the useful experimental data, the relative numbers of known compounds in which prototropic positions were often substituted by heavy atoms were also analysed. A scheme which groups all annular tautomeric transformations into 10 classes was developed. The scheme was designed to encompass a comprehensive set of known and theoretically possible tautomeric ring systems generated as part of a previous study. General trends across analogous ring systems were detected as a result. The calculations and statistics collected on crystallographic data as well as the general trends observed should be useful for the better modelling of annular tautomerism in the applications such as computer-aided drug design, small molecule crystal structure prediction, the naming of compounds and the interpretation of protein—small molecule crystal structures.

Partners | Office of Cancer Clinical Proteomics Research

Cancer.gov

Awardees and Affiliated Institutions Agilent Technologies, Inc., Cambridge, MA Baylor College of Medicine, Houston, TX Biomedical Hosting LLC, Arlington, MA Brigham and Women’s Hospital, Cambridge, MA Brown University, Providence, RI Cell Signaling Technology, Danvers, MA Chang Gung University, Molecular Medicine Research Center, Taoyuan City, Taiwan Dana-Farber Cancer Institute, Boston, MA Fluidigm Corp., Cambridge, MA

Geometry Report; Cambridge Conference on School Mathematics Feasibility Study No. 39.

ERIC Educational Resources Information Center

Stolzenberg, Gabriel

These materials were written with the aim of reflecting the thinking of the Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. This report deals with some seventh grade mathematical concepts taught at Cambridge Friends' School. The discovery approach was utilized by the teacher in order to…

The 'Naturals' and Victorian Cambridge: Reflections on the Anatomy of an Elite, 1851-1914.

ERIC Educational Resources Information Center

MacLeod, Roy; Moseley, Russell

1980-01-01

Explores how graduates of Cambridge University from 1851-1914 contributed expertise gained during their university years to British society, particularly the public sector in which they occupied many important positions. The term 'Naturals' refers to those who passed final exams in natural sciences and mathematics at Cambridge. (Author/DB)

The Use of Journal Clubs in Science Teacher Education

NASA Astrophysics Data System (ADS)

Tallman, Karen A.; Feldman, Allan

2016-04-01

This qualitative study explored how in a 7-month-long journal club pre- and inservice science teachers engaged with education research literature relevant to their practice to reduce the theory-practice gap. In the journal club they had the opportunity to critique and analyze peer-reviewed science education articles in the context of their classroom practice. Data sources included audio recordings of the meetings; semi-structured pre- and post-interviews of the teachers; focus groups; and artifacts (e.g., journal articles, reflective paper, email exchanges, and researcher's field notes). Data were analyzed using the techniques of grounded theory (Corbin & Strauss in Basics of qualitative research, 3rd ed. Sage, Thousand Oaks, 2008). In addition we used some preconceived categories that we created from existing literature on journal clubs and communities of practice (Newswander & Borrego in European Journal of Engineering Education 34(6): 561-571, 2009; Wenger in Communities of practice: learning, meaning, and identity. Cambridge University Press, Cambridge, 1998) and from our previous research (Tallman & Feldman, 2012). We found that the journal club incorporated the three characteristics of a community of practice (Wenger in Communities of practice: learning, meaning, and identity. Cambridge University Press, Cambridge, 1998) into its functioning (mutual engagement, joint enterprise, and shared repertoire). The teachers mutually engaged around the joint enterprise of reading, critiquing, and understanding the research studies with the goal of improving practice. The teachers also asked each other analytical questions, which became a shared repertoire of the journal club. They reflected on their practice by presenting, reading, and discussing the articles, which helped them to determine whether and how the findings from the articles could be incorporated into their teaching practice. In doing so, they learned the skills needed to critique the research literature in relation to their practice as classroom teachers.

Investigating the Impact of Cambridge International Assessments on U.S. Stakeholders: Student and Teacher Perceptions

ERIC Educational Resources Information Center

Shaw, Stuart

2011-01-01

As part of the continuing program to study the impact of its international assessments, the University of Cambridge International Examinations ("Cambridge") has undertaken a series of studies investigating the impact on a range of US stakeholders. This paper reports on research designed to respond to a series of washback and impact…

Alternative Force Structuring Strategies for Military Satellite Communication Systems

DTIC Science & Technology

1987-12-01

IC= -4 41 fu~- I C = C= C = Ac -- .G.. LILA ILIJ * 36 The following equation expresses how dBm power levels were calculated (33:120-121): dBm = 10...and Arms Control. Cambridge, Massachusetts: Abt Books, 1982. 16. Heffes, Harry and Anurag Kumar. "Stochastic Damage Models and Dependence Effects in

And Now What about Reforming Cambridge Governance?

ERIC Educational Resources Information Center

Evans, G. R.

2009-01-01

After its recent Assurance visit from HEFCE, Oxford went through a high profile public debate at the end of which its academic community voted against moving to a governance structure which would have given Oxford a majority of external members on its Council. The Higher Education Funding Council asked Oxford to answer eight questions justifying…

Self Concept in People with Williams Syndrome and Prader-Willi Syndrome

ERIC Educational Resources Information Center

Plesa-Skwerer, Daniela; Sullivan, Kate; Joffre, Kristen; Tager-Flusberg, Helen

2004-01-01

This study explored self concepts in matched groups of adolescents and adults with Williams syndrome (WS) and Prader-Willi syndrome (PWS), using Damon and Hart's [Self-understanding in Childhood and Adolescence, Cambridge University Press, New York, 1988] semi-structured interview. The main findings were that the WS participants were more…

An investigation into the impact of question structure on the performance of first year physics undergraduate students at the University of Cambridge

NASA Astrophysics Data System (ADS)

Gibson, Valerie; Jardine-Wright, Lisa; Bateman, Elizabeth

2015-07-01

We describe a study of the impact of exam question structure on the performance of first year Natural Sciences physics undergraduates from the University of Cambridge. The results show conclusively that a student’s performance improves when questions are scaffolded compared with university style questions. In a group of 77 female students we observe that the average exam mark increases by 13.4% for scaffolded questions, which corresponds to a 4.9 standard deviation effect. The equivalent observation for 236 male students is 9% (5.5 standard deviations). We also observe a correlation between exam performance and A2-level marks for UK students, and that students who receive their school education overseas, in a mixed gender environment, or at an independent school are more likely to receive a first class mark in the exam. These results suggest a mis-match between the problem-solving skills and assessment procedures between school and first year university and will provide key input into the future teaching and assessment of first year undergraduate physics students.

Asymptotic decay and non-rupture of viscous sheets

NASA Astrophysics Data System (ADS)

Fontelos, Marco A.; Kitavtsev, Georgy; Taranets, Roman M.

2018-06-01

For a nonlinear system of coupled PDEs, that describes evolution of a viscous thin liquid sheet and takes account of surface tension at the free surface, we show exponential (H^1, L^2) asymptotic decay to the flat profile of its solutions considered with general initial data. Additionally, by transforming the system to Lagrangian coordinates we show that the minimal thickness of the sheet stays positive for all times. This result proves the conjecture formally accepted in the physical literature (cf. Eggers and Fontelos in Singularities: formation, structure, and propagation. Cambridge Texts in Applied Mathematics, Cambridge, 2015), that a viscous sheet cannot rupture in finite time in the absence of external forcing. Moreover, in the absence of surface tension we find a special class of initial data for which the Lagrangian solution exhibits L^2-exponential decay to the flat profile.

Ask not what physics can do for biology--ask what biology can do for physics.

PubMed

Frauenfelder, Hans

2014-10-08

Stan Ulam, the famous mathematician, said once to Hans Frauenfelder: 'Ask not what Physics can do for biology, ask what biology can do for physics'. The interaction between biologists and physicists is a two-way street. Biology reveals the secrets of complex systems, physics provides the physical tools and the theoretical concepts to understand the complexity. The perspective gives a personal view of the path to some of the physical concepts that are relevant for biology and physics (Frauenfelder et al 1999 Rev. Mod. Phys. 71 S419-S442). Schrödinger's book (Schrödinger 1944 What is Life? (Cambridge: Cambridge University Press)), loved by physicists and hated by eminent biologists (Dronamraju 1999 Genetics 153 1071-6), still shows how a great physicist looked at biology well before the first protein structure was known.

Geometry at the aliphatic tertiary carbon atom: computational and experimental test of the Walsh rule.

PubMed

Böhm, Stanislav; Exner, Otto

2004-02-01

The geometrical parameters of molecules of 2-substituted 2-methylpropanes and 1-substituted bicyclo[2.2.2]octanes were calculated at the B3LYP/6-311+G(d,p) level. They agreed reasonably well with the mean crystallographic values retrieved from the Cambridge Structural Database for a set of diverse non-cyclic structures with a tertiary C atom. The angle deformations at this C atom produced by the immediately bonded substituent are also closely related to those observed previously in benzene mono derivatives (either as calculated or as derived from crystallographic data). The calculated geometrical parameters were used to test the classical Walsh rule: It is evidently true that an electron-attracting substituent increases the proportion of C-atom p-electrons in the bond to the substituent and leaves more s-electrons to the remaining bonds; as a consequence the C-C-C angles at a tertiary carbon are widened and the C-C bonds shortened. However, this rule describes only part of the reality since the bond angles and lengths are controlled by other factors as well, for instance by steric crowding. Another imperfection of the Walsh rule is that the sequence of substituents does not correspond to their electronegativities, as measured by any known scale; more probably it is connected with the inductive effect, but then only very roughly.

Chirality measures of α-amino acids.

PubMed

Jamróz, Michał H; Rode, Joanna E; Ostrowski, Sławomir; Lipiński, Piotr F J; Dobrowolski, Jan Cz

2012-06-25

To measure molecular chirality, the molecule is treated as a finite set of points in the Euclidean R(3) space supplemented by k properties, p(1)((i)), p(2)((i)), ..., p(k)((i)) assigned to the ith atom, which constitute a point in the Property P(k) space. Chirality measures are described as the distance between a molecule and its mirror image minimized over all its arbitrary orientation-preserving isometries in the R(3) × P(k) Cartesian product space. Following this formalism, different chirality measures can be estimated by taking into consideration different sets of atomic properties. Here, for α-amino acid zwitterionic structures taken from the Cambridge Structural Database and for all 1684 neutral conformers of 19 biogenic α-amino acid molecules, except glycine and cystine, found at the B3LYP/6-31G** level, chirality measures have been calculated by a CHIMEA program written in this project. It is demonstrated that there is a significant correlation between the measures determined for the α-amino acid zwitterions in crystals and the neutral forms in the gas phase. Performance of the studied chirality measures with changes of the basis set and computation method was also checked. An exemplary quantitative structure–activity relationship (QSAR) application of the chirality measures was presented by an introductory model for the benchmark Cramer data set of steroidal ligands of the sex-hormone binding globulin.

Structure-energy relationship in barbituric acid: a calorimetric, computational, and crystallographic study.

PubMed

Roux, María Victoria; Temprado, Manuel; Notario, Rafael; Foces-Foces, Concepción; Emel'yanenko, Vladimir N; Verevkin, Sergey P

2008-08-14

This paper reports the value of the standard (p(o) = 0.1 MPa) molar enthalpy of formation in the gas phase at T = 298.15 K for barbituric acid. The enthalpies of combustion and sublimation were measured by static bomb combustion calorimetry and transference (transpiration) method in a saturated N2 stream and a gas-phase enthalpy of formation value of -(534.3 +/- 1.7) kJ x mol(-1) was determined at T = 298.15 K. G3-calculated enthalpies of formation are in very good agreement with the experimental value. The behavior of the sample as a function of the temperature was studied by differential scanning calorimetry, and a new polymorph of barbituric acid at high temperature was found. In the solid state, two anhydrous forms are known displaying two out of the six hydrogen-bonding patterns observed in the alkyl/alkenyl derivatives retrieved from the Cambridge Crystallographic Database. The stability of these motifs has been analyzed by theoretical calculations. X-ray powder diffraction technique was used to establish to which polymorphic form corresponds to the commercial sample used in this study and to characterize the new form at high temperature.

Key considerations for the success of Medical Education Research and Innovation units in Canada: unit director perceptions.

PubMed

Varpio, Lara; Bidlake, Erin; Humphrey-Murto, Sue; Sutherland, Stephanie; Hamstra, Stanley J

2014-08-01

Growth in the field of medical education is evidenced by the proliferation of units dedicated to advancing Medical Education Research and Innovation (MERI). While a review of the literature discovered narrative accounts of MERI unit development, we found no systematic examinations of the dimensions of and structures that facilitate the success of these units. We conducted qualitative interviews with the directors of 12 MERI units across Canada. Data were analyzed using qualitative description (Sandelowski in Res Nurs Health 23:334-340, 2000). Final analysis drew on Bourdieu's (Outline of a theory of practice. Cambridge University Press, Cambridge, 1977; Media, culture and society: a critical reader. Sage, London, 1986; Language and symbolic power. Harvard University Press, Cambridge, 1991) concepts of field, habitus, and capital, and more recent research investigating the field of MERI (Albert in Acad Med 79:948-954, 2004; Albert et al. in Adv Health Sci Educ 12:103-115, 2007). When asked about the metrics by which they define their success, directors cited: teaching, faculty mentoring, building collaborations, delivering conference presentations, winning grant funding, and disseminating publications. Analyzed using Bourdieu's concepts, these metrics are discussed as forms of capital that have been legitimized in the MERI field. All directors, with the exception of one, described success as being comprised of elements (capital) at both ends of the service-research spectrum (i.e., Albert's PP-PU structure). Our analysis highlights the forms of habitus (i.e., behaviors, attitudes, demeanors) directors use to negotiate, strategize and position the unit within their local context. These findings may assist institutions in developing a new-or reorganizing an existing-MERI unit. We posit that a better understanding of these complex social structures can help units become savvy participants in the MERI field. With such insight, units can improve their academic output and their status in the MERI context-locally, nationally, and internationally.

Assessing the Impact of Arts and Humanities Research at the University of Cambridge. Technical Report

ERIC Educational Resources Information Center

Levitt, Ruth; Celia, Claire; Diepeveen, Stephanie; Chonaill, Siobhan Ni; Rabinovich, Lila; Tiessen, Jan

2010-01-01

This project for the University of Cambridge and the Arts and Humanities Research Council (AHRC) assesses the impacts of arts and humanities research at the University of Cambridge. Evidence from interviews, a survey of research staff and detailed case studies indicates that these disciplines already have a broad range of impacts. Many of these…

EDUCATION: Gates Gives Cambridge a Rival to Rhodes.

PubMed

Cohen, J

2000-10-20

Thanks to a new $210 million trust announced on 11 October by the Bill & Melinda Gates Foundation, Cambridge University is launching a new high-visibility scholars' program, which each year will fund at least 225 students from outside the United Kingdom. The university will select Gates Cambridge Scholars based on merit, not need, focusing on academic ability and leadership potential.

The Search for Suitable Strategy: Threat-Based and Capabilities-Based Strategies in a Complex World

DTIC Science & Technology

2016-05-26

subject to copyright, however further publication or sale of copyrighted images is not permissible. ii...Williamson Murray and Richard Hart Sinnreich, eds., Successful Strategies: Triumphing in War and Peace from Antiquity to the Present (Cambridge, United...Sinnreich, eds. Successful Strategies: Triumphing in War and Peace from Antiquity to the Present. Cambridge, United Kingdom: Cambridge University Press

Joint Services Electronics Program (Harvard University. Cambridge, Massachusetts)

DTIC Science & Technology

1988-09-30

34Band Structures of Semimagnetic Compounds," Acta Physica Polonica bf A73 (6), 933-941 (1988). (Partially supported by N00014-86-K-0760). c. Books...Journals K.L. Babcock and R.M. Westervelt, "Dynamics of Simple Electronic neural Net- works," Physica 28D, 305 (1987). C.M. Marcus and R.M. Westervelt

Insights into Hydrate Formation and Stability of Morphinanes from a Combination of Experimental and Computational Approaches

PubMed Central

2014-01-01

Morphine, codeine, and ethylmorphine are important drug compounds whose free bases and hydrochloride salts form stable hydrates. These compounds were used to systematically investigate the influence of the type of functional groups, the role of water molecules, and the Cl– counterion on molecular aggregation and solid state properties. Five new crystal structures have been determined. Additionally, structure models for anhydrous ethylmorphine and morphine hydrochloride dihydrate, two phases existing only in a very limited humidity range, are proposed on the basis of computational dehydration modeling. These match the experimental powder X-ray diffraction patterns and the structural information derived from infrared spectroscopy. All 12 structurally characterized morphinane forms (including structures from the Cambridge Structural Database) crystallize in the orthorhombic space group P212121. Hydrate formation results in higher dimensional hydrogen bond networks. The salt structures of the different compounds exhibit only little structural variation. Anhydrous polymorphs were detected for all compounds except ethylmorphine (one anhydrate) and its hydrochloride salt (no anhydrate). Morphine HCl forms a trihydrate and dihydrate. Differential scanning and isothermal calorimetry were employed to estimate the heat of the hydrate ↔ anhydrate phase transformations, indicating an enthalpic stabilization of the respective hydrate of 5.7 to 25.6 kJ mol–1 relative to the most stable anhydrate. These results are in qualitative agreement with static 0 K lattice energy calculations for all systems except morphine hydrochloride, showing the need for further improvements in quantitative thermodynamic prediction of hydrates having water···water interactions. Thus, the combination of a variety of experimental techniques, covering temperature- and moisture-dependent stability, and computational modeling allowed us to generate sufficient kinetic, thermodynamic and structural information to understand the principles of hydrate formation of the model compounds. This approach also led to the detection of several new crystal forms of the investigated morphinanes. PMID:25036525

Microscopy of semiconducting materials

NASA Astrophysics Data System (ADS)

Pennycook, S. J.

1991-04-01

The purpose of the trip was to present an invited talk at the 7th Oxford Conference on Microscopy of Semiconducting Materials entitled, High-Resolution Z-Contrast Imaging of Heterostructures and Superlattices, (Oxford, United Kingdom) and to visit VG Microscopes, East Grinstead, for discussions on the progress of the Oak Ridge National Laboratory (ORNL) 300-kV high-resolution scanning transmission electron microscope (STEM), which is currently on order. The traveler also visited three other institutions with 100-kV STEMs that either have or intend to purchase the necessary modifications to provide Z-contrast capability similar to that of the existing ORNL machine. Specifically, Max-Planck Institut fuer Metallforschung (Stuttgart, Germany); Cambridge University, Department of Materials Science and Metallurgy (Cambridge, United Kingdom); and Cavendish Laboratory, Cambridge University (Cambridge, United Kingdom) were visited. In addition, discussions were held with C. Humphreys on the possibility of obtaining joint funding for collaborative research involving electron beam writing and Z-contrast imaging in the Cambridge and Oak Ridge STEMs, respectively.

Ask not what physics can do for biology—ask what biology can do for physics

NASA Astrophysics Data System (ADS)

Frauenfelder, Hans

2014-10-01

Stan Ulam, the famous mathematician, said once to Hans Frauenfelder: ‘Ask not what Physics can do for biology, ask what biology can do for physics’. The interaction between biologists and physicists is a two-way street. Biology reveals the secrets of complex systems, physics provides the physical tools and the theoretical concepts to understand the complexity. The perspective gives a personal view of the path to some of the physical concepts that are relevant for biology and physics (Frauenfelder et al 1999 Rev. Mod. Phys. 71 S419-S442). Schrödinger’s book (Schrödinger 1944 What is Life? (Cambridge: Cambridge University Press)), loved by physicists and hated by eminent biologists (Dronamraju 1999 Genetics 153 1071-6), still shows how a great physicist looked at biology well before the first protein structure was known.

[Screening for depersonalization-derealization with two items of the cambridge depersonalization scale].

PubMed

Michal, Matthias; Zwerenz, Rüdiger; Tschan, Regine; Edinger, Jens; Lichy, Marcel; Knebel, A; Tuin, Inka; Beutel, Manfred

2010-05-01

Depersonalization (DP) and derealization (DR) are considered to be highly underdiagnosed. Therefore the development of screening instruments is important. From the Cambridge Depersonalization Scale (CDS) two items were extracted discriminating best patients with clinical significant DP from patients without DP. These two Items were assembled to a short version of the CDS. This short version (CDS-2) was tested in a sample of 38 patients with clinical significant DP-DR and 49 patients without or only mild DP-DR. Scores were compared against clinical diagnoses based on a structured interview (gold standard). The CDS-2 was able to differentiate patients with clinical significant DP well from other groups (cut-off of CDS-2>or=3, sensitivity=78.9%, specifity=85.7%) and also showed high reliability (Cronbachs alpha=0.92). Therefore the CDS-2 can be considered as a useful tool for screening and identification of DP-DR.

Book Review: Unifying scientific theories: physical concepts and mathematical structures. Margaret Morrison, Cambridge University Press, Cambridge, 2000, pp. 280, US 65.00, ISBN 0-521-65216-2 hardback

NASA Astrophysics Data System (ADS)

Debs, Talel A.

In addition to being a thorough and timely treatment of unity in science, Morrison's book is particularly noteworthy for the kind of inquiry it represents. In the context of current debates in the history and philosophy of science, Morrison has managed to chart a very persuasive middle path through potentially contentious extreme positions. Also, by taking an approach that is at once conceptual and historical, she has produced a book that truly addresses both the history and philosophy of modern science; it allows the reader to interact with key philosophical questions in addition to well researched and well documented historical accounts. These accounts, which function as case studies, are provided in Chapters 3-6. They are valuable both in-and-of themselves, and as examples which illustrate Morrison's main philosophical thesis.

Geotechnical centrifuge use at University of Cambridge Geotechnical Centre, August-September 1991

NASA Astrophysics Data System (ADS)

Gilbert, Paul A.

1992-01-01

A geotechnical centrifuge applies elevated acceleration to small-scale soil models to simulate body forces and stress levels characteristic of full-size soil structures. Since the constitutive behavior of soil is stress level development, the centrifuge offers considerable advantage in studying soil structures using models. Several experiments were observed and described in relative detail, including experiments in soil dynamics and liquefaction study, an experiment investigation leaning towers on soft foundations, and an experiment investigating migration of hot pollutants through soils.

The discovery of the structure of DNA

NASA Astrophysics Data System (ADS)

Squires, G. L.

2003-04-01

On 25 April 1953, Nature published a letter by Francis Crick and James Watson, at the Cavendish Laboratory, Cambridge, proposing a structure for DNA. This letter marked the beginning of a revolution in biology. Besides Crick and Watson, two other scientists, Rosalind Franklin and Maurice Wilkins, played key roles in the discovery. After sketching the early careers of the four scientists, the present article gives an account of the physics and chemistry involved in the discovery, and the events leading up to it.

European Science Notes Information Bulletin. Reports on Current European and Middle Eastern Science

DTIC Science & Technology

1993-01-01

network. Mechanical properties of ormolytes can tion of TiO2 to "open-up" the structure tb.r Li be modified by altering the structure of the silicate...Cambridge es. The group from the University of California, group has demonstrated that the color (wavelength) Santa Barbara, and Uniax Corporation...A.J. of the electroluminescence can be tuned over a Heeger, F. Wudi, P. Smith) reported on their work range of colors . with polymer 12 in several talks

Slavic Prosody: Language Change and Phonological Theory. Cambridge Studies in Linguistics 86.

ERIC Educational Resources Information Center

Bethin, Christina Yurkiw

The history of Slavic prosody gives an account of Slavic languages at the time of their differentiation and relates these developments to issues in phonological theory. It is first argued that the syllable structure of Slavic changes before the fall of the jers and suggests that intra- and intersyllabic reorganization in Late Common Slavic was far…

Evolving Agents: Communication and Cognition

DTIC Science & Technology

2005-06-01

systems [11] and the first Chomsky ideas concerning mechanisms of language grammar related to deep structure [12] encountered CC of rules. Model-based...Perennial (2000) 3. Jackendoff, R.: Foundations of Language: Brain, Meaning, Grammar , Evolution. Oxford University Press, New York, NY (2002) 4. Pinker, S... University Press, Princeton, NJ (1961) 11. Minsky, M.L.: Semantic Information Processing. The MIT Press, Cambridge, MA (1968) 12. Chomsky , N

The Private Military Firms: Historical Evolution and Industry Analysis

DTIC Science & Technology

2007-06-01

Company, Private Military Firm, Supply Push, Demand Pull, Future Projections, Blackwater, DynCorp, Entrepreneurship 16. PRICE CODE 17. SECURITY...Business Administration, University of California, 1995. Baumol, W. J. Entrepreneurship , Management, and the Structure of Payoffs. Cambridge, MA: The MIT...P. F. Innovation and Entrepreneurship : Practice and Principles. Toronto: Fitzhenry & Whiteside Limited, 1985. Duffy, M. When Private Armies Take to

Earth History databases and visualization - the TimeScale Creator system

NASA Astrophysics Data System (ADS)

Ogg, James; Lugowski, Adam; Gradstein, Felix

2010-05-01

The "TimeScale Creator" team (www.tscreator.org) and the Subcommission on Stratigraphic Information (stratigraphy.science.purdue.edu) of the International Commission on Stratigraphy (www.stratigraphy.org) has worked with numerous geoscientists and geological surveys to prepare reference datasets for global and regional stratigraphy. All events are currently calibrated to Geologic Time Scale 2004 (Gradstein et al., 2004, Cambridge Univ. Press) and Concise Geologic Time Scale (Ogg et al., 2008, Cambridge Univ. Press); but the array of intercalibrations enable dynamic adjustment to future numerical age scales and interpolation methods. The main "global" database contains over 25,000 events/zones from paleontology, geomagnetics, sea-level and sequence stratigraphy, igneous provinces, bolide impacts, plus several stable isotope curves and image sets. Several regional datasets are provided in conjunction with geological surveys, with numerical ages interpolated using a similar flexible inter-calibration procedure. For example, a joint program with Geoscience Australia has compiled an extensive Australian regional biostratigraphy and a full array of basin lithologic columns with each formation linked to public lexicons of all Proterozoic through Phanerozoic basins - nearly 500 columns of over 9,000 data lines plus hot-curser links to oil-gas reference wells. Other datapacks include New Zealand biostratigraphy and basin transects (ca. 200 columns), Russian biostratigraphy, British Isles regional stratigraphy, Gulf of Mexico biostratigraphy and lithostratigraphy, high-resolution Neogene stable isotope curves and ice-core data, human cultural episodes, and Circum-Arctic stratigraphy sets. The growing library of datasets is designed for viewing and chart-making in the free "TimeScale Creator" JAVA package. This visualization system produces a screen display of the user-selected time-span and the selected columns of geologic time scale information. The user can change the vertical-scale, column widths, fonts, colors, titles, ordering, range chart options and many other features. Mouse-activated pop-ups provide additional information on columns and events; including links to external Internet sites. The graphics can be saved as SVG (scalable vector graphics) or PDF files for direct import into Adobe Illustrator or other common drafting software. Users can load additional regional datapacks, and create and upload their own datasets. The "Pro" version has additional dataset-creation tools, output options and the ability to edit and re-save merged datasets. The databases and visualization package are envisioned as a convenient reference tool, chart-production assistant, and a window into the geologic history of our planet.

Bericht uber den 2. Internationalen Kongress fur Angewandte Linguistik. Cambridge 8.-12. IX. 1969. [Report on the Second International Congress for Applied Linguistics, Cambridge, Dec. 8-12, 1969.

ERIC Educational Resources Information Center

Mohr, Peter

This paper is a summary report on the Second International Congress of Applied Linguistics held in Cambridge, England in September 1969. Because of the large number of papers delivered, only a selection of the papers delivered in any one section of the Congress are considered, and the author attempts to identify current interests and trends in…

A first principles prediction of the crystal structure of C6Br2ClFH2

NASA Astrophysics Data System (ADS)

Misquitta, Alston J.; Welch, Gareth W. A.; Stone, Anthony J.; Price, Sarah L.

2008-04-01

We have constructed an intermolecular potential for the 1,3-dibromo-2-chloro-5-fluorobenzene molecule from first principles using SAPT(DFT) interaction energy calculations and the Williams-Stone-Misquitta method for obtaining molecular properties in distributed form. This molecule was included in the fourth Blind Test of crystal structure prediction organised by the Cambridge Crystallographic Data Centre. Using our potential, we have predicted the crystal structure of CBrClFH and found the lowest energy solution to be in excellent agreement with the experimentally observed crystal when it was subsequently revealed.

A Comparison of Quantum and Molecular Mechanical Methods to Estimate Strain Energy in Druglike Fragments.

PubMed

Sellers, Benjamin D; James, Natalie C; Gobbi, Alberto

2017-06-26

Reducing internal strain energy in small molecules is critical for designing potent drugs. Quantum mechanical (QM) and molecular mechanical (MM) methods are often used to estimate these energies. In an effort to determine which methods offer an optimal balance in accuracy and performance, we have carried out torsion scan analyses on 62 fragments. We compared nine QM and four MM methods to reference energies calculated at a higher level of theory: CCSD(T)/CBS single point energies (coupled cluster with single, double, and perturbative triple excitations at the complete basis set limit) calculated on optimized geometries using MP2/6-311+G**. The results show that both the more recent MP2.X perturbation method as well as MP2/CBS perform quite well. In addition, combining a Hartree-Fock geometry optimization with a MP2/CBS single point energy calculation offers a fast and accurate compromise when dispersion is not a key energy component. Among MM methods, the OPLS3 force field accurately reproduces CCSD(T)/CBS torsion energies on more test cases than the MMFF94s or Amber12:EHT force fields, which struggle with aryl-amide and aryl-aryl torsions. Using experimental conformations from the Cambridge Structural Database, we highlight three example structures for which OPLS3 significantly overestimates the strain. The energies and conformations presented should enable scientists to estimate the expected error for the methods described and we hope will spur further research into QM and MM methods.

Implications of Societal Fragmentation for State Formation: Can Democracy Succeed in Afghanistan

DTIC Science & Technology

2006-03-01

Conflict,” in Nationalism and Ethnic Conflict, Eds. Michael E. Brown, Owen R. Cote Jr., Sean M . Lynn-Jones, and Steven E. Miller (Cambridge and London: The...Cote Jr., Sean M . Lynn-Jones, and Steven E. Miller (Cambridge and London: The MIT Press, 1997), 49. 21 conceptions of legitimacy, they are...and Ethnic Conflict, Eds. Michael E. Brown, Owen R. Cote Jr., Sean M . Lynn-Jones, and Steven E. Miller (Cambridge and London: The MIT Press, 1997

The U.S., Japan, and Asia: Challenges to U.S. Policy

DTIC Science & Technology

1993-10-01

1945-1990. Cambridge: Cambridge UP, 1992. (E 183.8 .J3 B78 1992) Burks , Ardath W. Japan: A Postindustrial Power. 3rd ed. Boulder: Westview, 1991. (DS 806...1988) Anchordoguy, Marie . Computers Inc.: Japan’s Challenge to IB4. Cambridge: Harvard UP, 1989. (HD 9696 .C63 J29 1989) Arrison, Thomas S., et. al...Strategv towards the East. London: International Institute for Strategic Studies, 1984. (U 162 .A23 no.192) Burke , Patrick, ed. Nuclear Weapons World

Reflections on Heckman and Pinto’s Causal Analysis After Haavelmo

DTIC Science & Technology

2013-11-01

Econometric Analysis , Cambridge University Press, 477–490, 1995. Halpern, J. (1998). Axiomatizing causal reasoning. In Uncertainty in Artificial...Models, Structural Models and Econometric Policy Evaluation. Elsevier B.V., Amsterdam, 4779–4874. Heckman, J. J. (1979). Sample selection bias as a...Reflections on Heckman and Pinto’s “Causal Analysis After Haavelmo” Judea Pearl University of California, Los Angeles Computer Science Department Los

Second Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, volume 1

NASA Technical Reports Server (NTRS)

Giampapa, M. S. (Editor); Golub, L. (Editor)

1981-01-01

Solar and stellar atmospheric phenomena and their fundamental physical properties such as gravity, effective temperature and rotation rate, which provides the range in parameter space required to test various theoretical models were investigated. The similarity between solar activity and stellar activity is documented. Some of the topics discussed are: atmospheric structure, magnetic fields, solar and stellar activity, and evolution.

Training Metacognitive Skills for Situation Assessment

DTIC Science & Technology

1994-06-01

see Toulmin , 1978). The initial recognitional response to a cue provides its normal meaning. For example, the absence of enemy artillery within...Holland. Toulmin , S. (1958). The uses of argument. Cambridge, UK: Cambridge University Press.

The Life of James Clerk Maxwell

NASA Astrophysics Data System (ADS)

Campbell, Lewis; Garnett, William

2010-06-01

Preface; Part I. Biographical Outline: 1. Birth and parentage; 2. Glenlair - childhood, 1831-1841; 3. Boyhood, 1841-1844; 4. Adolescence, 1844-1847; 5. Opening manhood, 1847-1850; 6. Undergraduate life at Cambridge, 1850-1854; 7. Bachelor-scholar and fellow of Trinity, 1854-1856; 8. Essays at Cambridge, 1853-1856; 9. Death of his father. Professorship at Aberdeen, 1856-1857; 10. Aberdeen. Marriage, 1857-1860; 11. King's College, London. Glenair, 1860-1870; 12. Cambridge, 1871-1879; 13. Illness and death, 1879; 14. Last essays at Cambridge; Part II. Contributions to Science: 1. Experiments on colour vision, and other contributions to optics; 2. Investigations respecting elastic solids; 3. Pure geometry; 4. Mechanics; 5. Saturn's rings; 6. Faraday's lines of force, and Maxwell's theory of the electromagnetic field; 7. Molecular physics; Part III. Poems: 1. Juvenile verses and translations; 2. Occasional pieces; 3. Serio-comic verse; Index.

Highlights from SelectBio 2015: Academic Drug Discovery Conference, Cambridge, UK, 19-20 May 2015.

PubMed

Spencer, John; Coaker, Hannah

2015-01-01

The SelectBio 2015: Academic Drug Discovery Conference was held in Cambridge, UK, on 19-20 May 2015. Building on the success of academic drug discovery events in the USA, this conference aimed to showcase the exciting new research emerging from academic drug discovery and to help bridge the gap between basic research and commercial application. At the event the authors heard from a number of speakers on a broad array of topics, from partnering models for academia and industry to novel drug discovery approaches across various therapeutic areas, with a few talks, such as those by Susanne Muller-Knapp (Structure Genomics Consortium, Oxford University, Oxford, UK) and Julian Blagg (Institute of Cancer Research, UK), covering both remits, by highlighting a number of such partnerships and then delving into some case studies. The conference concluded with a heated debate on whether phenotypic discovery should be favored over targeted discovery in academia and pharma, in a panel discussion chaired by Roland Wolkowicz (San Diego State University, USA).

Formal verification of a microcoded VIPER microprocessor using HOL

NASA Technical Reports Server (NTRS)

Levitt, Karl; Arora, Tejkumar; Leung, Tony; Kalvala, Sara; Schubert, E. Thomas; Windley, Philip; Heckman, Mark; Cohen, Gerald C.

1993-01-01

The Royal Signals and Radar Establishment (RSRE) and members of the Hardware Verification Group at Cambridge University conducted a joint effort to prove the correspondence between the electronic block model and the top level specification of Viper. Unfortunately, the proof became too complex and unmanageable within the given time and funding constraints, and is thus incomplete as of the date of this report. This report describes an independent attempt to use the HOL (Cambridge Higher Order Logic) mechanical verifier to verify Viper. Deriving from recent results in hardware verification research at UC Davis, the approach has been to redesign the electronic block model to make it microcoded and to structure the proof in a series of decreasingly abstract interpreter levels, the lowest being the electronic block level. The highest level is the RSRE Viper instruction set. Owing to the new approach and some results on the proof of generic interpreters as applied to simple microprocessors, this attempt required an effort approximately an order of magnitude less than the previous one.

BV Quantization of the Rozansky-Witten Model

NASA Astrophysics Data System (ADS)

Chan, Kwokwai; Leung, Naichung Conan; Li, Qin

2017-10-01

We investigate the perturbative aspects of Rozansky-Witten's 3d {σ}-model (Rozansky and Witten in Sel Math 3(3):401-458, 1997) using Costello's approach to the Batalin-Vilkovisky (BV) formalism (Costello in Renormalization and effective field theory, American Mathematical Society, Providence, 2011). We show that the BV quantization (in Costello's sense) of the model, which produces a perturbative quantum field theory, can be obtained via the configuration space method of regularization due to Kontsevich (First European congress of mathematics, Paris, 1992) and Axelrod-Singer (J Differ Geom 39(1):173-213, 1994). We also study the factorization algebra structure of quantum observables following Costello-Gwilliam (Factorization algebras in quantum field theory, Cambridge University Press, Cambridge 2017). In particular, we show that the cohomology of local quantum observables on a genus g handle body is given by {H^*(X, (\\wedge^*T_X)^{⊗ g})} (where X is the target manifold), and we prove that the partition function reproduces the Rozansky-Witten invariants.

Arguments, contradictions, resistances, and conceptual change in students' understanding of atomic structure

NASA Astrophysics Data System (ADS)

Niaz, Mansoor; Aguilera, Damarys; Maza, Arelys; Liendo, Gustavo

2002-07-01

Most general chemistry courses and textbooks emphasize experimental details and lack a history and philosophy of science perspective. The objective of this study is to facilitate freshman general chemistry students' understanding of atomic structure based on the work of Thomson, Rutherford, and Bohr. It is hypothesized that classroom discussions based on arguments/counterarguments of the heuristic principles, on which these scientists based their atomic models, can facilitate students' conceptual understanding. This study is based on 160 freshman students enrolled in six sections of General Chemistry I (three sections formed part of the experimental group). All three models (Thomson, Rutherford, and Bohr) were presented to the experimental and control group students in the traditional manner, as found in most textbooks. After this, the three sections of the experimental group participated in the discussion of six items with alternative responses. Students were first asked to select a response and then participate in classroom discussions leading to arguments in favor or against the selected response and finally select a new response. Three weeks after having discussed the six items, both the experimental and control groups presented a monthly exam (based on the three models) and after another 3 weeks a semester exam. Results obtained show that given the opportunity to argue and discuss, students' understanding can go beyond the simple regurgitation of experimental details. Performance of the experimental group showed contradictions, resistances, and progressive conceptual change with considerable and consistent improvement in the last item. It is concluded that if we want our students to understand scientific progress and practice, then it is important that we include the experimental details not as a rhetoric of conclusions (Schwab, 1962, The teaching of science as enquiry, Cambridge, MA, Harward University Press; Schwab, 1974, Conflicting conceptions of curriculum, Berkeley, CA, McCutchan) but as heuristic principles (Lakatos, 1970, Criticism and the growth of knowledge, Cambridge, UK, Cambridge University Press, pp. 91-195), which were based on arguments, controversies, and interpretations of the scientists.

75 FR 11197 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Pistoia Alliance...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

...; CambridgeSoft, San Diego, CA; Merck, Boston, MA; Collaborative Drug Discovery, Burlingame, CA; Royal Society of Chemistry, Cambridge, UNITED KINGDOM; Thomson Reuters HealthCare and Science, Philadelphia, PA...

76 FR 57757 - Endangered Species; Receipt of Applications for Permit

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-16

....) held in zoos in the United States to the Department of Anthropology, University of Cambridge, Cambridge... activities to be conducted by the applicant over a 5-year period. Applicant: Los Angeles Zoo and Botanical...

Reading in developmental prosopagnosia: Evidence for a dissociation between word and face recognition.

PubMed

Starrfelt, Randi; Klargaard, Solja K; Petersen, Anders; Gerlach, Christian

2018-02-01

Recent models suggest that face and word recognition may rely on overlapping cognitive processes and neural regions. In support of this notion, face recognition deficits have been demonstrated in developmental dyslexia. Here we test whether the opposite association can also be found, that is, impaired reading in developmental prosopagnosia. We tested 10 adults with developmental prosopagnosia and 20 matched controls. All participants completed the Cambridge Face Memory Test, the Cambridge Face Perception test and a Face recognition questionnaire used to quantify everyday face recognition experience. Reading was measured in four experimental tasks, testing different levels of letter, word, and text reading: (a) single word reading with words of varying length,(b) vocal response times in single letter and short word naming, (c) recognition of single letters and short words at brief exposure durations (targeting the word superiority effect), and d) text reading. Participants with developmental prosopagnosia performed strikingly similar to controls across the four reading tasks. Formal analysis revealed a significant dissociation between word and face recognition, as the difference in performance with faces and words was significantly greater for participants with developmental prosopagnosia than for controls. Adult developmental prosopagnosics read as quickly and fluently as controls, while they are seemingly unable to learn efficient strategies for recognizing faces. We suggest that this is due to the differing demands that face and word recognition put on the perceptual system. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Sparkle/AM1 Parameters for the Modeling of Samarium(III) and Promethium(III) Complexes.

PubMed

Freire, Ricardo O; da Costa, Nivan B; Rocha, Gerd B; Simas, Alfredo M

2006-01-01

The Sparkle/AM1 model is extended to samarium(III) and promethium(III) complexes. A set of 15 structures of high crystallographic quality (R factor < 0.05 Å), with ligands chosen to be representative of all samarium complexes in the Cambridge Crystallographic Database 2004, CSD, with nitrogen or oxygen directly bonded to the samarium ion, was used as a training set. In the validation procedure, we used a set of 42 other complexes, also of high crystallographic quality. The results show that this parametrization for the Sm(III) ion is similar in accuracy to the previous parametrizations for Eu(III), Gd(III), and Tb(III). On the other hand, promethium is an artificial radioactive element with no stable isotope. So far, there are no promethium complex crystallographic structures in CSD. To circumvent this, we confirmed our previous result that RHF/STO-3G/ECP, with the MWB effective core potential (ECP), appears to be the most efficient ab initio model chemistry in terms of coordination polyhedron crystallographic geometry predictions from isolated lanthanide complex ion calculations. We thus generated a set of 15 RHF/STO-3G/ECP promethium complex structures with ligands chosen to be representative of complexes available in the CSD for all other trivalent lanthanide cations, with nitrogen or oxygen directly bonded to the lanthanide ion. For the 42 samarium(III) complexes and 15 promethium(III) complexes considered, the Sparkle/AM1 unsigned mean error, for all interatomic distances between the Ln(III) ion and the ligand atoms of the first sphere of coordination, is 0.07 and 0.06 Å, respectively, a level of accuracy comparable to present day ab initio/ECP geometries, while being hundreds of times faster.

5-Arylidene derivatives of Meldrum's acid: Synthesis, structural characterization using single crystal and powder crystal X-ray diffraction, and electronic properties

NASA Astrophysics Data System (ADS)

Dey, Tanusri; Ghosh, Soumen; Ghosh, Somnath; Mukherjee, Alok Kumar

2015-07-01

Four 5-arylidene derivatives of Meldrum's acid, 5-(4-chlorobenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (2), 5-(3-hydroxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (3), 5-(3,4-dimethoxybenzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (4) and 5-(2,4-dimethoxy benzylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione (5) have been synthesized and their crystal structures have been determined using single crystal X-ray diffractometry for 2, 4 and 5 and X-ray powder diffraction for 3. The nature of intermolecular interactions in 2-5 has been analyzed through Hirshfeld surfaces and 2D fingerprint plots. The DFT optimized molecular geometries in 2-5 agree closely with those obtained from the crystallographic studies. The crystal packing in 2-5 exhibits an interplay of Osbnd H⋯O, Csbnd H⋯O, Csbnd H⋯Cl and Csbnd H⋯π (arene) hydrogen bonds and π⋯π interactions, which assemble molecules into three-dimensional architecture in 2, 3 and 5 and two-dimensional framework in 4. The Hirshfeld surface analyses of 2-5, Meldrum's acid (1) and a few related 5-arylidene derivatives of Meldrum's acid retrieved from the Cambridge Structural Database (CSD) indicate that about 85% of the Hirshfeld surface area (72% in 2 where H⋯Cl contribution is about 13%) in this class of compounds are due to H⋯H, O⋯H and C⋯H contacts. The HOMO-LUMO energy gap (>2.2 eV) in 2-5 indicates a significant degree of internal charge transfer within the molecule.

Cambridge Safer Truck Initiative : Vehicle-Based Strategies to Protect Pedestrians and Bicyclists

DOT National Transportation Integrated Search

2016-03-01

This report summarizes Volpe, The National Transportation Systems Centers (Volpes) research and recommendations for the City of Cambridge for implementing a number of proven vehicle safety strategies, including truck side guards, blind spot mir...

Theory of Effectiveness Measurement

DTIC Science & Technology

2006-09-01

features, or properties). These attributes can be either directly or indirectly observable ( Cropley , 1998:238). Additionally, a system embodies a set...John Shawe-Taylor, An Introduction to Support Vector Machines, Cambridge University Press, Cambridge, 2000. Cropley , D. H., “Towards Formulating a

When are Overcomplete Topic Models Identifiable? Uniqueness of Tensor Tucker Decompositions with Structured Sparsity

DTIC Science & Technology

2013-08-14

Communications and Computing, Electrical Engineering and Computer Science Dept., University of California, Irvine, USA 92697. Email : a.anandkumar...uci.edu,mjanzami@uci.edu. Daniel Hsu and Sham Kakade are with Microsoft Research New England, 1 Memorial Drive, Cambridge, MA 02142. Email : dahsu...Andreas Maurer, Massimiliano Pontil, and Bernardino Romera-Paredes. Sparse coding for multitask and transfer learning. ArxXiv preprint, abs/1209.0738, 2012

Who do you know? Developing and Analyzing Entrepreneur Networks: An Analysis of the Tech Entrepreneurial Environment of Six African Cities

DTIC Science & Technology

2015-01-01

2013, 2014, 2015) Greve, A. and Salaff, J. W. (2003), Social Networks and Entrepreneurship . Entrepreneurship Theory and Practice , 28: 1–22. doi...Social Capital: A Theory of Structure and Action. Cambridge University Press, New York 2001. Liu, Y., Slotine, J., and Barabasi, A. (2011...success of start-ups. Entrepreneurship and Regional Development. 16:391–412.

State of the Art of Natural Language Processing

DTIC Science & Technology

1987-11-15

work of Chomsky , Hewlett-Packard, Generalized Phase Structure Grammar . D. Lunar, DARPA speech understanding, Schank’s Conceptual Dependency Theory...of computers that a machine which understood natural languages was highly desirable. It also was evident from the work of Chomsky * and others that...computers. ♦Noam Chomsky , Aspects of the Theory of Syntax (Cambridge, Mass.: MIT Press, 1965). -A- One of the earliest attempts at Natural Language

Data Acquisition and Preparation for Social Network Analysis Based on Email: Lessons Learned

DTIC Science & Technology

2009-06-01

Mrvar , A., and Batagelj , V. (2005), Exploratory Social Network Analysis with Pajek (Structural Analysis in the Social Sciences series). Cambridge, New...visualization of large networks. This program was developed by Vladimir Batagelj and Andrej Mrvar of the University of Ljubljana in Slovenia. Pajek evolved...theory, presumes Wasserman & Faust as foundation Amazon: 55% purchase rate among viewers 5. de Nooy, W., Mrvar , A., and Batagelj , V. (2005

12. Historic American Buildings Survey Photocopy of ink on linen ...

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

12. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts ATTIC PLAN - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

11. Historic American Buildings Survey Photocopy of ink on linen ...

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

11. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts SECOND FLOOR PLAN - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

9. Historic American Buildings Survey Photocopy of ink on linen ...

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

9. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts BASEMENT PLAN - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

10. Historic American Buildings Survey Photocopy of ink on linen ...

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

10. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts FIRST FLOOR PLAN - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

6. Historic American Buildings Survey Photocopy of ink on linen ...

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

6. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts SOUTH ELEVATION DRAWING - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

7. Historic American Buildings Survey Photocopy of ink on linen ...

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

7. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts EAST ELEVATION DRAWING - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

8. Historic American Buildings Survey Photocopy of ink on linen ...

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

8. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts NORTH ELEVATION DRAWING - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

5. Historic American Buildings Survey Photocopy of ink on linen ...

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

5. Historic American Buildings Survey Photocopy of ink on linen drawing dated 1878, Longfellow & Clark, in possession of owner, 70 Sparks Street, Cambridge Street, Massachusetts WEST ELEVATION DRAWING - Edward S. Dodge House, 70 Sparks Street, Cambridge, Middlesex County, MA

Some reminiscences about my early career

NASA Astrophysics Data System (ADS)

Domb, Cyril

1990-09-01

The author recalls some of the highlights of his scientific career before he took up a professional appointment at King's College, London in 1954. The periods covered are: High School and undergraduate studies at Cambridge University 1932-1941; radar research for the British Admiralty 1941-1946; graduate studies at Cambridge University 1946-1949; post-doctoral research at the Clarendon Laboratory, Oxford University 1949-1952; faculty appointment at Cambridge University 1952-1954. A brief description is given of the personalities with whom the author was associated, the research problems in which he was involved, and of the early post world war 2 scientific conferences.

Water quality in the Cambridge, Massachusetts, drinking-water source area, 2005-8

USGS Publications Warehouse

Smith, Kirk P.; Waldron, Marcus C.

2015-01-01

During 2005-8, the U.S. Geological Survey, in cooperation with the Cambridge, Massachusetts, Water Department, measured concentrations of sodium and chloride, plant nutrients, commonly used pesticides, and caffeine in base-flow and stormwater samples collected from 11 tributaries in the Cambridge drinking-water source area. These data were used to characterize current water-quality conditions, to establish a baseline for future comparisons, and to describe trends in surface-water quality. The data also were used to assess the effects of watershed characteristics on surface-water quality and to inform future watershed management.

Polymorphism in R-tamsulosin (an alpha blocker): The unexpected manifestation of a sulfonamide⋯o-diethoxybenzene heterosynthon

NASA Astrophysics Data System (ADS)

Nanubolu, Jagadeesh Babu; Sridhar, Balasubramanian; Ravikumar, Krishnan

2014-12-01

A two point Nsbnd H⋯O dimer or an infinite catemer are the most preferred motifs/synthons for sulfonamide structures. Such synthons are known to be so robust that they are only disrupted in the presence of highly activated O acceptors such as pyridine-N-oxide and sulfoxide. We demonstrate in this article that a multi-point synthon offered by much weaker ethoxy O and amine N acceptors can however strongly compete and disrupt the robust sulfonamide homosynthons. This has been illustrated with the synthon analysis in three polymorphic crystal structures of R-tamsulosin, an active drug used in the treatment of Benign Prostatic Hyperplasia (BPH) and its hydrochloride salt. These crystalline solids are characterized by Single crystal X-ray diffraction (SC-XRD), powder X-ray diffraction (PXRD), Fourier Transform Infrared (FT-IR) and Raman spectroscopy. Forms I, II of the free base and hydrochloride salt crystallize in the monoclinic P21, C2, and P21 space groups respectively with two molecules in the asymmetric unit (Z‧ = 2), whereas, form III of freebase crystallize in the orthorhombic P212121 space group with Z‧ = 1. Remarkably, all four crystal structures contain a totally unexpected sulfonamide⋯o-diethoxybenzene heterosynthon. The multi-point motifs observed in polymorphs are relatively stronger than those in the hydrochloride salt because of the gauche conformation of the tamsulosin linker chain which renders an additional hydrogen bond interaction with amine N acceptor, and resemble the crown ether sulfonamide recognition pattern. Observation of this new heterosynthon offers potential scope in the design of pharmaceutical cocrystals for sulfonamide bearing drug molecules. The present study also presents a detailed hydrogen bond motif analysis in 310 primary sulfonamide structures culled from the latest version of Cambridge Structural Database (CSD). The role of various competing groups is discussed in the context of understanding the most recurring sulfonamide homo and heterosynthons.

4. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. ...

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

4. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. - Erie Railway, Parallel French Creek Bridges, 100 feet South of Millers Station Road, 0.4 mile Northeast of State Route 408, 0.9 mile East of Cambridge Springs, Cambridge Springs, Crawford County, PA

2. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. ...

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

2. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. - Erie Railway, Parallel French Creek Bridges, 100 feet South of Millers Station Road, 0.4 mile Northeast of State Route 408, 0.9 mile East of Cambridge Springs, Cambridge Springs, Crawford County, PA

3. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. ...

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

3. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. - Erie Railway, Parallel French Creek Bridges, 100 feet South of Millers Station Road, 0.4 mile Northeast of State Route 408, 0.9 mile East of Cambridge Springs, Cambridge Springs, Crawford County, PA

1. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. ...

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

1. July 1971. AERIAL RECONNAISSANCE II, ERIE RAILWAY SURVEY. - Erie Railway, Parallel French Creek Bridges, 100 feet South of Millers Station Road, 0.4 mile Northeast of State Route 408, 0.9 mile East of Cambridge Springs, Cambridge Springs, Crawford County, PA

Cambridge Desegregation Succeeding.

ERIC Educational Resources Information Center

Alves, Michael

1983-01-01

This paper provides an overview of the controversy concerning "freedom of choice" desegregation plans and presents a case study of the plan adopted by Cambridge, Massachusetts, in 1981. Following the introduction, a short explanation of the plan's distinctive feature, controlled open enrollment, is given. (Under controlled open…

Ecology for conserving our sirenians

USGS Publications Warehouse

Bonde, Robert K.

2012-01-01

Review of: Ecology and conservation of the sirenia: dugongs and manatees. Helene Marsh, Thomas J. O'Shea and John E. Reynolds III. Cambridge University Press, Cambridge, 2012, 521 pp, ISBN 978-0-521-88828-8, US$135 and 978-0-521-71643-7, US$65.

Implementation and evaluation of a hypercube-based method for spatiotemporal exploration and analysis

NASA Astrophysics Data System (ADS)

Marchand, Pierre; Brisebois, Alexandre; Bédard, Yvan; Edwards, Geoffrey

This paper presents the results obtained with a new type of spatiotemporal topological dimension implemented within a hypercube, i.e., within a multidimensional database (MDDB) structure formed by the conjunction of several thematic, spatial and temporal dimensions. Our goal is to support efficient SpatioTemporal Exploration and Analysis (STEA) in the context of Automatic Position Reporting System (APRS), the worldwide amateur radio system for position report transmission. Mobile APRS stations are equipped with GPS navigation systems to provide real-time positioning reports. Previous research about the multidimensional approach has proved good potential for spatiotemporal exploration and analysis despite a lack of explicit topological operators (spatial, temporal and spatiotemporal). Our project implemented such operators through a hierarchy of operators that are applied to pairs of instances of objects. At the top of the hierarchy, users can use simple operators such as "same place", "same time" or "same time, same place". As they drill down into the hierarchy, more detailed topological operators are made available such as "adjacent immediately after", "touch during" or more detailed operators. This hierarchy is structured according to four levels of granularity based on cognitive models, generalized relationships and formal models of topological relationships. In this paper, we also describe the generic approach which allows efficient STEA within the multidimensional approach. Finally, we demonstrate that such an implementation offers query run times which permit to maintain a "train-of-thought" during exploration and analysis operations as they are compatible with Newell's cognitive band (query runtime<10 s) (Newell, A., 1990. Unified theories of cognition. Harvard University Press, Cambridge MA, 549 p.).

EPOS--The European E-Portfolio of Languages

ERIC Educational Resources Information Center

Kühn, Bärbel

2016-01-01

Democratic principles and human rights, the core values of the Council of Europe, informed the development of the "Common European Framework of Reference for Languages" (CEFR; Council of Europe 2001. "Common European framework of reference for languages: Learning, teaching, assessment." Cambridge: Cambridge University Press.…

A Robust Method of Measuring Other-Race and Other-Ethnicity Effects: The Cambridge Face Memory Test Format

PubMed Central

McKone, Elinor; Stokes, Sacha; Liu, Jia; Cohan, Sarah; Fiorentini, Chiara; Pidcock, Madeleine; Yovel, Galit; Broughton, Mary; Pelleg, Michel

2012-01-01

Other-race and other-ethnicity effects on face memory have remained a topic of consistent research interest over several decades, across fields including face perception, social psychology, and forensic psychology (eyewitness testimony). Here we demonstrate that the Cambridge Face Memory Test format provides a robust method for measuring these effects. Testing the Cambridge Face Memory Test original version (CFMT-original; European-ancestry faces from Boston USA) and a new Cambridge Face Memory Test Chinese (CFMT-Chinese), with European and Asian observers, we report a race-of-face by race-of-observer interaction that was highly significant despite modest sample size and despite observers who had quite high exposure to the other race. We attribute this to high statistical power arising from the very high internal reliability of the tasks. This power also allows us to demonstrate a much smaller within-race other ethnicity effect, based on differences in European physiognomy between Boston faces/observers and Australian faces/observers (using the CFMT-Australian). PMID:23118912

On the Use of Offensive Cyber Capabilities: A Policy Analysis on Offensive US Cyber Policy

DTIC Science & Technology

2012-03-20

greater success in addressing systemic issues with the current networking structures in cyberspace (such as IPv4 , and border gateway protocol (BGP...PERFORMING ORGANIZATION NAME(S) AND ADDRESS (ES) Harvard Kennedy School,79 John F. Kennedy Street,Cambridge,MA,02138 8. PERFORMING ORGANIZATION...REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS (ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12

Using Structured Knowledge Representation for Context-Sensitive Probabilistic Modeling

DTIC Science & Technology

2008-01-01

Morgan Kaufmann, 1988. [24] J. Pearl, Causality: Models, Reasoning, and Inference, Cambridge University Press, 2000. [25] J. Piaget , Piaget’s theory ...5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( S ) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES...AGENCY NAME( S ) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM( S ) 11. SPONSOR/MONITOR’S REPORT NUMBER( S ) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved

Structures and Functions of Selective Attention.

DTIC Science & Technology

1987-07-20

phonological and semantic representations in memory ( LaBerge & Samuels, 1974; Marcel, 1983; Posner, 1978). The advantage of an integrated word, even in...0014-86-0289 and by the McDonnell Center for Higher Brain Function. I am grateful to Drs. Mary K. Rothbart, Steven E. Petersen and Jennifer Sandson...benefit of cost and benefit. Psychology Bulletin, 1984, 96, 29-44. Kosslyn, S.M. (1980) Image and Mind. Harvard Press, Cambridge, MA. LaBerge , D.L

Integrated Software Development System/Higher Order Software Conceptual Description (ISDS/HOS)

DTIC Science & Technology

1976-11-01

Structured Flowchart Conventions 270 6.3.5.3 Design Diagram Notation 273 xii HIGHER ORDER SOFTWARE, INC. 843 MASSACHUSETTS AVENUE. CAMBRIDGE, MASSACHUSETTS...associated with the process steps. They also reference other HIPO diagrams as well an non-HIPO documentation such as flowcharts or decision tables of...syntax that is easy to learn and must provide the novice with some prompting to help him avoid classic beginner errors. Desirable editing capabilities

Oral Histories in Meteoritics and Planetary Science - XV: John Wood

NASA Astrophysics Data System (ADS)

Sears, Derek W. G.

2012-05-01

John Wood (Fig. 1) was trained in Geology at Virginia Tech and M.I.T. To fulfill a minor subject requirement at M.I.T., he studied astronomy at Harvard, taking courses with Fred Whipple and others. Disappointed at how little was known in the 1950s about the origin of the earth, he seized an opportunity to study a set of thin sections of stony meteorites, on the understanding that these might shed light on the topic. This study became his Ph.D. thesis. He recognized that chondrites form a metamorphic sequence, and that idea proved surprisingly hard to sell. After brief service in the Army and a year at Cambridge University, John served for 3 years as a research associate with Ed Anders at the University of Chicago. He then returned to the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, where he spent the remainder of his career. At Chicago, he investigated the formation of the Widmanstätten structure, and found that the process informs us of the cooling rates of iron meteorites. Back in Cambridge, he collaborated with W. R. Van Schmus on a chondrite classification that incorporates metamorphic grade, and published on metal grains in chondrites, before becoming absorbed by preparations for the return of lunar samples by the Apollo astronauts. His group's work on Apollo samples helped to establish the character of the lunar crust, and the need for a magma ocean to form it. Wood served as President of the Meteoritical Society in 1971-72 and received the Leonard Medal in 1978.

Performance on Cambridge Neuropsychological Test Automated Battery subtests sensitive to frontal lobe function in people with autistic disorder: evidence from the Collaborative Programs of Excellence in Autism network.

PubMed

Ozonoff, Sally; Cook, Ian; Coon, Hilary; Dawson, Geraldine; Joseph, Robert M; Klin, Ami; McMahon, William M; Minshew, Nancy; Munson, Jeffrey A; Pennington, Bruce F; Rogers, Sally J; Spence, M Anne; Tager-Flusberg, Helen; Volkmar, Fred R; Wrathall, Debora

2004-04-01

Recent structural and functional imaging work, as well as neuropathology and neuropsychology studies, provide strong empirical support for the involvement of frontal cortex in autism. The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a computer-administered set of neuropsychological tests developed to examine specific components of cognition. Previous studies document the role of frontal cortex in performance of two CANTAB subtests: the Stockings of Cambridge, a planning task, and the Intradimensional/Extradimensional Shift task, a measure of cognitive set shifting. To examine the integrity of frontal functions, these subtests were administered to 79 participants with autism and 70 typical controls recruited from seven universities who are part of the Collaborative Programs of Excellence in Autism network. The two groups were matched on age, sex, and full-scale IQ. Significant group differences were found in performance on both subtests, with the autism group showing deficits in planning efficiency and extradimensional shifting relative to controls. Deficits were found in both lower- and higher-IQ individuals with autism across the age range of 6 to 47 years. Impairment on the CANTAB executive function subtests did not predict autism severity or specific autism symptoms (as measured by the ADI-R and ADOS), but it was correlated with adaptive behavior. If these CANTAB subtests do indeed measure prefrontal function, as suggested by previous research with animals and lesion patients, this adds to the accumulating evidence of frontal involvement in autism and indicates that this brain region should remain an active area of investigation.

Progressive sparse representation-based classification using local discrete cosine transform evaluation for image recognition

NASA Astrophysics Data System (ADS)

Song, Xiaoning; Feng, Zhen-Hua; Hu, Guosheng; Yang, Xibei; Yang, Jingyu; Qi, Yunsong

2015-09-01

This paper proposes a progressive sparse representation-based classification algorithm using local discrete cosine transform (DCT) evaluation to perform face recognition. Specifically, the sum of the contributions of all training samples of each subject is first taken as the contribution of this subject, then the redundant subject with the smallest contribution to the test sample is iteratively eliminated. Second, the progressive method aims at representing the test sample as a linear combination of all the remaining training samples, by which the representation capability of each training sample is exploited to determine the optimal "nearest neighbors" for the test sample. Third, the transformed DCT evaluation is constructed to measure the similarity between the test sample and each local training sample using cosine distance metrics in the DCT domain. The final goal of the proposed method is to determine an optimal weighted sum of nearest neighbors that are obtained under the local correlative degree evaluation, which is approximately equal to the test sample, and we can use this weighted linear combination to perform robust classification. Experimental results conducted on the ORL database of faces (created by the Olivetti Research Laboratory in Cambridge), the FERET face database (managed by the Defense Advanced Research Projects Agency and the National Institute of Standards and Technology), AR face database (created by Aleix Martinez and Robert Benavente in the Computer Vision Center at U.A.B), and USPS handwritten digit database (gathered at the Center of Excellence in Document Analysis and Recognition at SUNY Buffalo) demonstrate the effectiveness of the proposed method.

Two new species of the genus Paramitraceras Pickard-Cambridge, 1905 (Opiliones: Laniatores: Stygnopsidae) from Chiapas, Mexico.

PubMed

Cruz-López, Jesús A; Francke, Oscar F

2013-01-01

Parainitraceras pickardcanibridgei sp. nov. and Paramitraceras tzotzil sp. nov. from Chiapas, Mexico are described based on specimens previously determined as Paramitraceras granulatum Pickard-Cambridge, 1905 by Goodnight and Goodnight. The male genitalia of the new species and P. granulatum are illustrated with scanning electronic micrographs (SEMs) or drawings derived from them. The importance of the ocular tubercle, cheliceral dentition and sexual dimorphism, pedipalpal armature and male genitalia as taxonomic characters within the genus is discussed as well as differences and similarities between Paramitraceras Pickard-Cambridge, 1905 and its most similar genus, Sbordonia Šilhavý, 1977.

The Ancients' Appliance of Science

ERIC Educational Resources Information Center

Stephenson, Philip; Sword, Frances

2004-01-01

An innovative collaboration between the Fitzwilliam Museum in Cambridge and the University of Cambridge Faculty of Education encourages new questions to be asked of ancient objects. In the museum galleries children work directly from ancient Egyptian objects through activities designed to encourage questioning that unpicks the technologies of the…

An Alternative Approach to the Variable Housing Allowance Program

DTIC Science & Technology

1987-01-01

ACOL values. 1T CBO, p. 31. tm Angus Deaton and John Muellbauer, Economics and Consumer Behavior (New York: Cambridge University Press, 1980), p...London: Chapman and Hall, 1975. Deaton A. S. and J. Muellbauer. Economics and Consumer Behavior . New York« Cambridge University Press, 1980

Neural Networks Applied to Signal Processing

DTIC Science & Technology

1989-09-01

Distributed Processing, The MIT Press, Cambridge, MA, 1988. 3. Marvin Minsky and Seymour Papert, Perceptrons, The MIT Press, Cambridge, MA, 1969. 4...signum function, the linear function, and the sigmoid function. Initial research conducted in the 1950’s and 1960’s by Rosenblat, Minsky and others used

Decision Topology Assessment in Engineering Design Under Uncertainity

DTIC Science & Technology

2014-01-01

those of the United States Government or the DoA, and shall not be used for advertising or product endorsement purposes. REFERENCES 1. Clemen ...Raiffa, H., 1994, Decisions with Multiple Objectives, Cambridge University Press, Cambridge, United Kingdom. 6. Lewis, K., W. Chen, and L.C. Schmidt

77 FR 46120 - Notice of Inventory Completion: Peabody Museum of Archaeology and Ethnology, Harvard University...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-02

... Inventory Completion: Peabody Museum of Archaeology and Ethnology, Harvard University, Cambridge, MA... Museum of Archaeology and Ethnology, Harvard University, Cambridge, MA. The human remains and associated..., Repatriation Coordinator, Peabody Museum of Archaeology and Ethnology, Harvard University, 11 Divinity Avenue...

76 FR 5829 - Manufacturer of Controlled Substances; Notice of Registration

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-02

... 1, 2010, 75 FR 53719, Cambridge Isotope Lab, 50 Frontage Road, Andover, Massachusetts 01810, made... determined that the registration of Cambridge Isotope Lab to manufacture the listed basic class of controlled substance is consistent with the public interest at this time. DEA has [[Page 5830

BOOK REVIEW Exact Space-Times in Einstein's General Relativity Exact Space-Times in Einstein's General Relativity

NASA Astrophysics Data System (ADS)

Lake, Kayll

2010-12-01

The title immediately brings to mind a standard reference of almost the same title [1]. The authors are quick to point out the relationship between these two works: they are complementary. The purpose of this work is to explain what is known about a selection of exact solutions. As the authors state, it is often much easier to find a new solution of Einstein's equations than it is to understand it. Even at first glance it is very clear that great effort went into the production of this reference. The book is replete with beautifully detailed diagrams that reflect deep geometric intuition. In many parts of the text there are detailed calculations that are not readily available elsewhere. The book begins with a review of basic tools that allows the authors to set the notation. Then follows a discussion of Minkowski space with an emphasis on the conformal structure and applications such as simple cosmic strings. The next two chapters give an in-depth review of de Sitter space and then anti-de Sitter space. Both chapters contain a remarkable collection of useful diagrams. The standard model in cosmology these days is the ICDM model and whereas the chapter on the Friedmann-Lemaître-Robertson-Walker space-times contains much useful information, I found the discussion of the currently popular a representation rather too brief. After a brief but interesting excursion into electrovacuum, the authors consider the Schwarzschild space-time. This chapter does mention the Swiss cheese model but the discussion is too brief and certainly dated. Space-times related to Schwarzschild are covered in some detail and include not only the addition of charge and the cosmological constant but also the addition of radiation (the Vaidya solution). Just prior to a discussion of the Kerr space-time, static axially symmetric space-times are reviewed. Here one can find a very interesting discussion of the Curzon-Chazy space-time. The chapter on rotating black holes is rather brief and, for example, does not contain reference to the insights found by Pretorius and Israel [2]. This is perhaps justifiable in view of the many specialized texts devoted to the Kerr space-time (e.g. [3]). The large clear diagrams that one becomes accustomed to in this book show off the Taub-NUT (and related) space-times in the next chapter. After perhaps a somewhat standard discussion of stationary axially symmetric space-times, there is a very informative discussion of accelerating black holes. For example, the global structure of the C-metric is considered in detail. This is followed by a brief discussion of solutions for uniformly accelerating particles. The discussion of the Plebański-Demiański solutions contains two very useful flow charts that help to systematize two rather complex families of solutions. After a somewhat brief discussion of plane and pp-waves, the authors give an extensive discussion of the Kunt solutions. I note here that after this text was in production the importance of the Kunt space-times as regards the characterization of space-times by scalar curvature invariants was made clear [4]. The discussion of the Robinson-Trautman solutions that follows is extensive, containing, for example, details of the singularity structure and of the global structure. The final formal chapter in this text covers colliding plane waves. This contains, for example, discussions of the Khan-Penrose, Ferrari-Ibañez and Chandrasekhar-Xanthopoulos solutions. The text ends with a `final miscellany'. This covers a number of interesting topics, but I found the discussion of the Lemaître-Tolman solutions rather weak (compare e.g. [5]). The book has two quite useful appendices covering 2-spaces and 3-spaces of constant curvature. To conclude, I will quote from the dust jacket: `The book is an invaluable resource for both graduate students and academic researchers working in gravitational physics'. I highly recommend it. References [1] Stephani H, Kramer D, MacCallum M, Hoenselaers C and Herlt E 2003 Exact Solutions of Einstein's Field Equations (Second Edition) (Cambridge: Cambridge University Press) [2] Pretorius F and Israel W 1998 Class. Quantum Grav.15 2289 [3] Wiltshire D, Visser M and Scott S (ed) 2008 The Kerr Spacetime: Rotating Black Holes in General Relativity (Cambridge: Cambridge University Press) [4] Coley A, Hervik S and Pelavas N 2009 Class. Quantum Grav. 26 025013 [5] Plebański J and Krasiński A 2006 An Introduction to General Relativity and Cosmology (Cambridge: Cambridge University Press)

Structural failure; International Symposium on Structural Crashworthiness, 2nd, Massachusetts Institute of Technology, Cambridge, June 6-8, 1988, Invited Lectures

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

Wierzbicki, T.; Jones, N.

1989-01-01

The book discusses the fragmentation of solids under dynamic loading, the debris-impact protection of space structures, the controlled fracturing of structures by shock-wave interaction and focusing, the tearing of thin metal sheets, and the dynamic inelastic failure of beams, and dynamic rupture of shells. Consideration is also given to investigations of the failure of brittle and composite materials by numerical methods, the energy absorption of polymer matrix composite structures (frictional effects), the mechanics of deep plastic collapse of thin-walled structures, the denting and bending of tubular beams under local loads, the dynamic bending collapse of strain-softening cantilever beams, and themore » failure of bar structures under repeated loading. Other topics discussed are on the behavior of composite and metallic superstructures under blast loading, the catastrophic failure modes of marine structures, and industrial experience with structural failure.« less

75 FR 16178 - Antitrust Division

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-31

... Production Act of 1993--Joint Venture Agreement Between Cambridge Major Laboratories, Inc. and Konarka... Production Act of 1993, 15 U.S.C. 4301 et seq. (``the Act''), Joint Venture Agreement Between Cambridge Major... to the venture and (2) the nature and objectives of the venture. The notifications were filed for the...

Gendered Language in Interactive Discourse

ERIC Educational Resources Information Center

Hussey, Karen A.; Katz, Albert N.; Leith, Scott A.

2015-01-01

Over two studies, we examined the nature of gendered language in interactive discourse. In the first study, we analyzed gendered language from a chat corpus to see whether tokens of gendered language proposed in the gender-as-culture hypothesis (Maltz and Borker in "Language and social identity." Cambridge University Press, Cambridge, pp…

An Evaluation of the Compressive Properties of Helmet Pads Pre- and Post-Shock Wave Overpressure Exposure

DTIC Science & Technology

2015-08-14

by ANSI Std. Z39.18 BLAST DROP TESTS BRAIN DAMAGE VISCOELASTICITY BRAIN CONCUSSION ...Cambridge, UK: Cambridge University Press, 1997. [5] W. C. Moss and M. J. King, "Impact response of US Army and National Football League helmet pad

Oxbridge Redivivus

ERIC Educational Resources Information Center

Ainley, Patrick

2011-01-01

How the dominance of the two medieval universities, namely, (1) The University of Oxford; and (2) The University of Cambridge, was gained and maintained is the subject of the institutional histories by Gillian Evans. She has long been a thorn in the side of successive Cambridge Vice-Chancellors' aspirations to turn that institution--at which she…

The Linguistically Aware Teacher and the Teacher-Aware Linguist

ERIC Educational Resources Information Center

McCartney, Elspeth; Ellis, Sue

2013-01-01

This review evaluates issues of teacher linguistic knowledge relating to their work with children with speech, language and communication difficulties (SLCD). Information is from Ellis and McCartney [(2011a). "Applied linguistics and primary school teaching." Cambridge: Cambridge University Press], a state-of-the-art text deriving from a British…

Embedding Sustainable Development at Cambridge University Engineering Department

ERIC Educational Resources Information Center

Fenner, Richard A.; Ainger, Charles M.; Cruickshank, Heather J.; Guthrie, Peter M.

2005-01-01

Purpose--The paper seeks to examine the latest stage in a process of change aimed at introducing concepts of sustainable development into the activities of the Department of Engineering at Cambridge University, UK. Design/methodology/approach--The rationale behind defining the skills which future engineers require is discussed and vehicles for…

Dynamics of and Characteristics of Numerical Models of Weakly Nonlinear Flows

DTIC Science & Technology

1997-09-30

for Environmental Science 2020 Horns Point Road PO Box 775 Cambridge, MD 21613-0775 phone: (410) 221-8477 fax: (410) 221-8490 email: walstad...AND ADDRESS(ES) University of Maryland Center for Environmental Science ,Horn Point Laboratory,2020 Horns Point Road,Cambridge,MD,21613-0775 8

New Frontiers: Moving the Humanities Model of Curricular Development.

ERIC Educational Resources Information Center

Grady, Elizabeth

1995-01-01

The American Council of Learned Societies (ACLS) humanities model in the Cambridge (Massachusetts) public schools has significantly affected curricular reform and teacher development. The endeavor is in its third year at the Pilot School, a program within the Cambridge Rindge and Latin School. The article describes progressive reform experiences…

77 FR 3118 - Security Zone; Choptank River and Cambridge Channel, Cambridge, MD

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-23

... security regimes designed to safeguard human life, vessels, and waterfront facilities while still... restriction of vessel traffic is necessary to protect life, property and the environment, therefore, a 30-day... maritime safety and security in order to safeguard life, property, and the environment on or near the...

Aligning ESP Courses with the "Common European Framework of Reference for Languages"

ERIC Educational Resources Information Center

Athanasiou, Androulla; Constantinou, Elis Kakoulli; Neophytou, Maro; Nicolaou, Anna; Papadima Sophocleous, Salomi; Yerou, Christina

2016-01-01

This article explains how the "Common European Framework of References for Languages" (CEFR; Council of Europe 2001, "Common European Framework of Reference for Languages: Learning, teaching, assessment." Cambridge: Cambridge University Press) has been applied in language courses at the Language Centre (LC) of the Cyprus…

Psychiatry in the Harvard Medical School-Cambridge Integrated Clerkship: An Innovative, Year-Long Program

ERIC Educational Resources Information Center

Griswold, Todd; Bullock, Christopher; Gaufberg, Elizabeth; Albanese, Mark; Bonilla, Pedro; Dvorak, Ramona; Epelbaum, Claudia; Givon, Lior; Kueppenbender, Karsten; Joseph, Robert; Boyd, J. Wesley; Shtasel, Derri

2012-01-01

Objective: The authors present what is to their knowledge the first description of a model for longitudinal third-year medical student psychiatry education. Method: A longitudinal, integrated psychiatric curriculum was developed, implemented, and sustained within the Harvard Medical School-Cambridge Integrated Clerkship. Curriculum elements…

75 FR 58431 - Notice of Inventory Completion: Peabody Museum of Archaeology and Ethnology, Harvard University...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-24

... Archaeology and Ethnology, Harvard University, Cambridge, MA; Correction AGENCY: National Park Service... in the possession of the Peabody Museum of Archaeology and Ethnology, Harvard University, Cambridge... was a project of Harvard University faculty in 1972. No known individuals were identified. No...

The Growth of Economic Studies at Cambridge: 1776-1860.

ERIC Educational Resources Information Center

Rashid, Salim

1980-01-01

Traces the resistance toward establishing an economics curriculum at Cambridge University from 1776 to 1860. Complex reasons include inertia, low intellectual standards, fear of being considered partisan, and avoidance of change during good times. The eventual introduction of economics was achieved only when wholesale reforms were enacted within…

Testing the English of Foreign Students in 1930.

ERIC Educational Resources Information Center

Spolsky, Bernard

Tests of English for foreign students conducted by the University of Cambridge Local Examinations Syndicate (England) and the Educational Testing Service were recognized as equivalent, though different in form and approach, in the 1930s. The underlying goal of the Cambridge certificate of proficiency was control of the English curriculum of…

A teaching skills assessment tool inspired by the Calgary-Cambridge model and the patient-centered approach.

PubMed

Sommer, Johanna; Lanier, Cédric; Perron, Noelle Junod; Nendaz, Mathieu; Clavet, Diane; Audétat, Marie-Claude

2016-04-01

The aim of this study was to develop a descriptive tool for peer review of clinical teaching skills. Two analogies framed our research: (1) between the patient-centered and the learner-centered approach; (2) between the structures of clinical encounters (Calgary-Cambridge communication model) and teaching sessions. During the course of one year, each step of the action research was carried out in collaboration with twelve clinical teachers from an outpatient general internal medicine clinic and with three experts in medical education. The content validation consisted of a literature review, expert opinion and the participatory research process. Interrater reliability was evaluated by three clinical teachers coding thirty audiotaped standardized learner-teacher interactions. This tool contains sixteen items covering the process and content of clinical supervisions. Descriptors define the expected teaching behaviors for three levels of competence. Interrater reliability was significant for eleven items (Kendall's coefficient p<0.05). This peer assessment tool has high reliability and can be used to facilitate the acquisition of teaching skills. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Scaling and allometry in the building geometries of Greater London

NASA Astrophysics Data System (ADS)

Batty, M.; Carvalho, R.; Hudson-Smith, A.; Milton, R.; Smith, D.; Steadman, P.

2008-06-01

Many aggregate distributions of urban activities such as city sizes reveal scaling but hardly any work exists on the properties of spatial distributions within individual cities, notwithstanding considerable knowledge about their fractal structure. We redress this here by examining scaling relationships in a world city using data on the geometric properties of individual buildings. We first summarise how power laws can be used to approximate the size distributions of buildings, in analogy to city-size distributions which have been widely studied as rank-size and lognormal distributions following Zipf [ Human Behavior and the Principle of Least Effort (Addison-Wesley, Cambridge, 1949)] and Gibrat [ Les Inégalités Économiques (Librarie du Recueil Sirey, Paris, 1931)]. We then extend this analysis to allometric relationships between buildings in terms of their different geometric size properties. We present some preliminary analysis of building heights from the Emporis database which suggests very strong scaling in world cities. The data base for Greater London is then introduced from which we extract 3.6 million buildings whose scaling properties we explore. We examine key allometric relationships between these different properties illustrating how building shape changes according to size, and we extend this analysis to the classification of buildings according to land use types. We conclude with an analysis of two-point correlation functions of building geometries which supports our non-spatial analysis of scaling.

Characterization of non-classical Csbnd Br⋯π interactions in (E)-1,3-dibromo-5-(2-(ferrocenyl)vinyl)benzene and related derivatives of ferrocene

NASA Astrophysics Data System (ADS)

Shukla, Rahul; Panini, Piyush; McAdam, C. John; Robinson, Brian H.; Simpson, Jim; Tagg, Tei; Chopra, Deepak

2017-03-01

Amongst the halogens, the involvement of bromine atoms in various types of intermolecular interactions is comparatively the least studied. In this manuscript, we report the formation of Csbnd Br⋯π interactions, with the π-rings being the cyclopentadienyl (Cp) rings of a ferrocene molecule in a newly synthesized compound (E)-1,3-dibromo-5-(2-(ferrocenyl)vinyl)benzene. We have also performed a detailed quantitative analysis on Csbnd Br⋯π interactions observed in the synthesized molecule and in several related molecules found in the Cambridge Structure Database (CSD) showing the presence of these interactions. A topological analysis based upon QTAIM theory and electrostatic potential ESP mapped on the Hirshfeld surface of these molecules confirm that these interactions are better described as "halogen bonds" wherein the electropositive region (σ-hole) on the Br-atom interacts with the electronegative region over the Cp-ring of the ferrocene. Further, the electronegative region on the bromine atom (perpendicular to the Csbnd Br bond) was observed to be involved in the formation of highly directional Csbnd H⋯Br interactions with the ∠Csbnd Br⋯H close to 90°. Thus the bromine atom is acting as both a "halogen bond donor" and "hydrogen bond acceptor" in the crystal packing with the two interactions being mutually orthogonal.

New developments in crystallography: exploring its technology, methods and scope in the molecular biosciences.

PubMed

Helliwell, John R

2017-08-31

Since the Protein Data Bank (PDB) was founded in 1971, there are now over 120,000 depositions, the majority of which are from X-ray crystallography and 90% of those made use of synchrotron beamlines. At the Cambridge Structure Database (CSD), founded in 1965, there are more than 800,000 'small molecule' crystal structure depositions and a very large number of those are relevant in the biosciences as ligands or cofactors. The technology for crystal structure analysis is still developing rapidly both at synchrotrons and in home labs. Determination of the details of the hydrogen atoms in biological macromolecules is well served using neutrons as probe. Large multi-macromolecular complexes cause major challenges to crystallization; electrons as probes offer unique advantages here. Methods developments naturally accompany technology change, mainly incremental but some, such as the tuneability, intensity and collimation of synchrotron radiation, have effected radical changes in capability of biological crystallography. In the past few years, the X-ray laser has taken X-ray crystallography measurement times into the femtosecond range. In terms of applications many new discoveries have been made in the molecular biosciences. The scope of crystallographic techniques is indeed very wide. As examples, new insights into chemical catalysis of enzymes and relating ligand bound structures to thermodynamics have been gained but predictive power is seen as not yet achieved. Metal complexes are also an emerging theme for biomedicine applications. Our studies of coloration of live and cooked lobsters proved to be an unexpected favourite with the public and schoolchildren. More generally, public understanding of the biosciences and crystallography's role within the field have been greatly enhanced by the United Nations International Year of Crystallography coordinated by the International Union of Crystallography. This topical review describes each of these areas along with illustrative results to document the scope of each methodology. © 2017 The Author(s).

Designing the Desired State: A Process and Model for Operational Design

DTIC Science & Technology

2010-04-01

Riper and my mentor Dr. Frank Marlo for their insights and assistance in this endeavor. I also need to thank my family. My wife Melanie was not only...FMI 5-2. (Washington, DC.: U.S. Department of the Army, FebiUary 20, 2009), 18 . 11 Melanie Stofka, a professional artist, assisted Major Jon Stofka...May 2009. Klein , Gary. Sources of Power: How People Make Decisions. Cambridge, Massachusetts: The MIT Press, 1998. Kuhn, Thomas S. The Structure

Design, Synthesis, and Chemical Processing of Hierarchical Ceramic Structures for Aerospace Applications

DTIC Science & Technology

1993-03-30

Massachusetts Institute of Technology, Cambridge, MA 02139I ABSTRACT polysilanes." Pyrolysis of these polymers usually The decomposition of polymeric SiC ...of soluble polymeric solids. Pyrolysis of these polymers in argon yielded The precursors were prepared by adding a TiC/A120 3 composite at 12501C...formation of soluble polymeric solids. Pyrolysis described an approach for synthesizing AI2O/ SiC of these polymers in argon yielded TiC/AI203

Arbitrary amplitude electrostatic wave propagation in a magnetized dense plasma containing helium ions and degenerate electrons

NASA Astrophysics Data System (ADS)

Mahmood, S.; Sadiq, Safeer; Haque, Q.; Ali, Munazza Z.

2016-06-01

The obliquely propagating arbitrary amplitude electrostatic wave is studied in a dense magnetized plasma having singly and doubly charged helium ions with nonrelativistic and ultrarelativistic degenerate electrons pressures. The Fermi temperature for ultrarelativistic degenerate electrons described by N. M. Vernet [(Cambridge University Press, Cambridge, 2007), p. 57] is used to define ion acoustic speed in ultra-dense plasmas. The pseudo-potential approach is used to solve the fully nonlinear set of dynamic equations for obliquely propagating electrostatic waves in a dense magnetized plasma containing helium ions. The upper and lower Mach number ranges for the existence of electrostatic solitons are found which depends on the obliqueness of the wave propagation with respect to applied magnetic field and charge number of the helium ions. It is found that only compressive (hump) soliton structures are formed in all the cases and only subsonic solitons are formed for a singly charged helium ions plasma case with nonrelativistic degenerate electrons. Both subsonic and supersonic soliton hump structures are formed for doubly charged helium ions with nonrelativistic degenerate electrons and ultrarelativistic degenerate electrons plasma case containing singly as well as doubly charged helium ions. The effect of propagation direction on the soliton amplitude and width of the electrostatic waves is also presented. The numerical plots are also shown for illustration using dense plasma parameters of a compact star (white dwarf) from literature.

The afterlife of Laurence Sterne (1713-1768): Body snatching, dissection and the role of Cambridge anatomist Charles Collignon.

PubMed

Dittmar, Jenna M; Mitchell, Piers D

2016-11-01

This paper aims to highlight the practice of body snatching from graves in the 1700s for the purpose of providing corpses for anatomical dissection, and for stocking anatomy museums. To do this, we examine the exhumation and dissection of the famous eighteenth-century novelist Laurence Sterne and explore the involvement of Charles Collignon, Professor of Anatomy at the University of Cambridge. We also show that osteological and cut-mark analysis of a skull purported to be that of Sterne, currently housed in the Duckworth Collection at Cambridge, provides the key to solving the mystery surrounding why Sterne was resurrected. © The Author(s) 2015.

The Best That Has Been Thought and Said?

ERIC Educational Resources Information Center

Alexander, Robin

2014-01-01

"FORUM" has marked the progress of the Cambridge Primary Review by three previous articles from Robin Alexander, the Review's director, and by critiques and responses from several others, notably "FORUM"'s Michael Armstrong. In 2013 the Review was superseded by the Cambridge Primary Review Trust, and this article is the text of…

Self-Access and the Adult Language Learner.

ERIC Educational Resources Information Center

Esch, Edith, Ed.

The immediate stimulus for this collection of papers was a conference, Self-Access and the Adult Language Learner, organized by the Centre for Information on Language Teaching and Research (CILT) and the Language Centre of the University of Cambridge in December 1992 at Queen's College, Cambridge. Several 1-day conferences on the same theme were…

77 FR 9682 - Announcement of Funding Awards for the HUD-Veterans Affairs Supportive Housing (HUD-VASH) Program...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-17

... 35804 84,762 25 City of Huntsville. NE. HA Tuscaloosa 2117 Jack Warner Tuscaloosa...... AL 35401 96,333... Street.... Boston MA 02111 520,356 50 Cambridge Housing Authority.. 675 Massachusetts Cambridge....... MA 02139 350,721 25 Avenue. Worcester Housing Authority.. 40 Belmont Street.... Worcester....... MA 01605...

Genetic Influences on Cognitive Function Using the Cambridge Neuropsychological Test Automated Battery

ERIC Educational Resources Information Center

Singer, Jamie J.; MacGregor, Alex J.; Cherkas, Lynn F.; Spector, Tim D.

2006-01-01

The genetic relationship between intelligence and components of cognition remains controversial. Conflicting results may be a function of the limited number of methods used in experimental evaluation. The current study is the first to use CANTAB (The Cambridge Neuropsychological Test Automated Battery). This is a battery of validated computerised…

Final Report of Cambridge Conference on School Mathematics, January 1962 - August 1970.

ERIC Educational Resources Information Center

Cambridge Conference on School Mathematics, Newton, MA.

The Cambridge Conference on School Mathematics (CCSM) was an association of prominent mathematicians who had a concern for mathematics education at school level, from kindergarten through grade twelve. These mathematicians organized three main conferences in three areas of mathematics education, and have carried on activities related to the…

[Probability, Cambridge Conference on School Mathematics Feasibility Study No. 7.

ERIC Educational Resources Information Center

Davis, R.

These materials were written with the aim of reflecting the thinking of the Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. They represent a practical response to a proposal by CCSM that some elements of probability be introduced in the elementary grades. These materials provide children…

Trust-Based Cooperative Games and Control Strategies for Autonomous Military Convoys

DTIC Science & Technology

2013-01-01

52] S. Goering, "Postnatal Reproductive Autonomy: Promoting Relational Autonomy and Self-Trust in New Parents," Bioethics , vol. 23, no. 1, pp. 9-19...Systems," Proceedings of the IEEE, vol. 95, no. 1, pp. 215-233, January 2007. [105] O. O’Neill, Autonomy and Trust in Bioethics . Cambridge: Cambridge

The Just Community School: The Theory and the Cambridge Cluster School Experiment.

ERIC Educational Resources Information Center

Kohlberg, Lawrence; And Others

The background, evaluation process, theories, and practical aspects of the Just Community High School in Cambridge, Masachusetts, are presented. The document is organized into four sections. Section 1 briefly discusses the components of a Just School: participatory democracy with teachers and students having equal rights, emphasis on conflict…

Stacking up against Alternative Conceptions: Using Uno Cards to Introduce Discourse and Argumentation

ERIC Educational Resources Information Center

Dunac, Patricia S.; Demi, Kadir

2013-01-01

We engaged secondary science students in a teacher and student constructed Uno card game (UCG) to change their conceptual understanding of the various energy transformations. The paper outlines how we incorporated Toulmin's argumentation pattern (Toulmin 1958 "The Uses of Argument"(Cambridge: Cambridge University Press)) in the UCG,…

The Cambridge Companion to Dewey. Cambridge Companions to Philosophy

ERIC Educational Resources Information Center

Cochran, Molly

2010-01-01

John Dewey (1859-1952) was a major figure of the American cultural and intellectual landscape in the first half of the twentieth century. While not the originator of American pragmatism, he was instrumental to its articulation as a philosophy and the spread of its influence beyond philosophy to other disciplines. His prolific writings encompass…

Argumentation and Participation Patterns in General Chemistry Peer-Led Sessions

ERIC Educational Resources Information Center

Kulatunga, Ushiri; Moog, Richard S.; Lewis, Jennifer E.

2013-01-01

This article focuses on the use of Toulmin's argumentation scheme to investigate the characteristics of student group argumentation in Peer-Led Guided Inquiry sessions for a General Chemistry I course. A coding scheme based on Toulmin's [Toulmin [1958] "The uses of argument." Cambridge: Cambridge University Press] argumentation…

Developing Outcome Measures for a Family Intensive Support Service for Children Presenting with Challenging Behaviours

ERIC Educational Resources Information Center

Mulligan, Bethany; John, Mary; Coombes, Rachel; Singh, Rosemary

2015-01-01

Seven per cent of individuals with learning disabilities also display challenging behaviour ("Challenging behaviour: analysis and intervention in people with severe intellectual disabilities," 2001, Cambridge, Cambridge University Press), which has an effect on the whole family. Services need to be developed to support and reflect this…

The Visual Identity Project

ERIC Educational Resources Information Center

Tennant-Gadd, Laurie; Sansone, Kristina Lamour

2008-01-01

Identity is the focus of the middle-school visual arts program at Cambridge Friends School (CFS) in Cambridge, Massachusetts. Sixth graders enter the middle school and design a personal logo as their first major project in the art studio. The logo becomes a way for students to introduce themselves to their teachers and to represent who they are…

Massive Molecular Outflows and Evidence for AGN Feedback from CO Observations

DTIC Science & Technology

2013-11-13

J. Thomson Avenue, Cambridge CB3 0HE, UK e-mail: c.cicone@mrao.cam.ac.uk 2 Kavli Institute for Cosmology , University of Cambridge, Madingley Road...molecular outflow as a function of AGN luminosity. Theoretical models of AGN feed- back and cosmological simulations predict a coupling efficiency between AGN

Aerodynamics Education: Where We’ve Been and Where We’re Going

DTIC Science & Technology

2013-06-24

2661. June 1992. 3 Kroo. I.. "Aerodynamic Analyses for Design and Education ... AIAA Paper 92-2664 . . lune 1992. 12 American Institute of Aeronautics...Paper 98-2792 . . lune 1998. 13 Anderson. J.D .. A l-/ist01y <~/Aero<~wwmics. Cambridge Univers ity Press. Cambridge. 1998. 14http

Coastal Marine Demonstration of Forecast Information to Mariners for the U.S. East Coast

DTIC Science & Technology

1998-09-30

Maryland Center for Environmental Science PO Box 775 Cambridge, MD 21613-0775 410.221.8477 fax:410.221.8490 walstad@hpl.umces.edu George L. Mellor... Environmental Science ,PO Box 775,Cambridge,MD,21613-0775 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES

Legacies, Policies and Prospects: One Year on from the Cambridge Primary Review

ERIC Educational Resources Information Center

Alexander, Robin

2011-01-01

This article features the "Cambridge Primary Review." The "Review" has been supported from the beginning by Esmee Fairbairn Foundation, and this has given it the independence which is essential to its credibility. Its remit was to investigate, report and make recommendations on the condition and future of primary education in…

How to Run a University

ERIC Educational Resources Information Center

Evans, G. R.

2006-01-01

The Lambert Review of Business-University Collaboration proposed a business model for universities in 2003. Pressure to change university governance to make it match the business model remains strong, and it is being most actively applied to Oxford and Cambridge. The Oxford and Cambridge governance debates (which began in the 1990s) open up the…

The Singapore-Cambridge General Certificate of Education Advanced-Level General Paper Examination

ERIC Educational Resources Information Center

Hassan, Nurul Huda; Shih, Chih-Min

2013-01-01

This article describes and reviews the Singapore-Cambridge General Certificate of Education Advanced Level General Paper (GP) examination. As a written test that is administered to preuniversity students, the GP examination is internationally recognised and accepted by universities and employers as proof of English competence. In this article, the…

Using the Concordancer in Vocabulary Development for the Cambridge Advanced English (CAE) Course.

ERIC Educational Resources Information Center

Somogyi, Emma

1996-01-01

Discusses concordancing activities tailored for use with English-as-a-Second-Language (ESL) students in the Cambridge Advanced English course in Australia. The article focuses on students selecting appropriate vocabulary to complete gapped text. Findings indicate that these activities benefit ESL students by providing authentic examples of…

Democratic Consolidation and Comparative Political Perspective on the 2002 Presidential Election in the ROK

DTIC Science & Technology

2005-01-01

combining presidential system with legislature where no single party has majority status is a kiss of death.”52 According to Giovanni Sartori , the...Cheibub and Limongi, “What Makes Democracies Endure?” p. 46. 53 Giovanni Sartori , Parties and Party Systems (Cambridge: Cambridge University Press

A Computerized Three-Dimensional Program Budget and Its Implementation at Cambridge School Department.

ERIC Educational Resources Information Center

Wong, S. Godwin

This report describes the APL (Accountable unit, Program, and line item) budget system, a computerized three-dimensional program budget system that has been implemented in the Cambridge (Massachusetts) School Department. Various chapters discuss the differences between traditional budgeting and program budgeting, present an overview of te APL…

Accounting Community of Practice Pedagogy: A Course Management Invention for Developing Personal Competencies in Accounting Education

ERIC Educational Resources Information Center

Stephenson, Sandria S.

2017-01-01

This paper reports the findings of an exploratory qualitative study using the implementation of Wenger's [(1998). "Communities of practice: Learning, meaning, and identity." Cambridge, MA: Cambridge University Press; Wenger, E. (2000). Communities of practice and social learning systems. "Organization," 7(2), 225-246] Theory of…

Linguistic Turn and Gendering Language in the Cambridge Advanced Learner's Dictionary

ERIC Educational Resources Information Center

Arimbi, Diah A.; Kwary, Deny A.

2016-01-01

Language constructs how humans perceive things. Since language is a human construction, it tends to be biased as it is mainly men's construction. Using gender perspectives, this paper attempts to discuss the imbalance in gender representations found in the examples given in an English learner's dictionary, that is, the "Cambridge Advanced…

What To Look for in ESL Admission Tests: Cambridge Certificate Exams, IELTS, and TOEFL.

ERIC Educational Resources Information Center

Chalhoub-Deville, Micheline; Turner, Carolyn E.

2000-01-01

Familiarizes test users with issues to consider when employing assessments for screening and admission purposes. Examines the purpose, content, and scoring methods of three English-as-a-Second-Language admissions tests--the Cambridge certificate exams, International English Language Teaching System, and Test of English as a Foreign…

Learner Diary Research with "Cambridge" Examination Candidates.

ERIC Educational Resources Information Center

Parkinson, Brian; Benson, Cathy; Jenkins, Michael

2003-01-01

This paper describes a research project in which volunteers, self-selected from IALS students preparing for one or more of the Cambridge English Examinations, kept journals. Following guidelines, they reflected on their in-class and outside-of-class experiences in the 8 weeks leading up to the exams. They also attended four biweekly meetings with…

Physical Fitness of U.S. Navy Special Forces Team Members and Trainees

DTIC Science & Technology

1989-07-07

Resting Heart Rate and Blood Pressure. At the completion of a 12-lead resting EKG (VS4S, Cambridge Instrument Co., Ossining , NY), heart rate (bpm) of...Cambridge Instrument Co., Ossining , NY). Instruments were interfaced with a MINC-23 computer (Digital Equipment Corp., Marlboro, MA) for on-line

Multifaceted impairments in impulsivity and brain structural abnormalities in opioid dependence and abstinence.

PubMed

Tolomeo, S; Gray, S; Matthews, K; Steele, J D; Baldacchino, A

2016-10-01

Chronic opioid exposure, as a treatment for a variety of disorders or as drug of misuse, is common worldwide, but behavioural and brain abnormalities remain under-investigated. Only a small percentage of patients who receive methadone maintenance treatment (MMT) for previous heroin misuse eventually achieve abstinence and studies on such patients are rare. The Cambridge Neuropsychological Test Automated Battery and T1 weighted magnetic resonance imaging (MRI) were used to study a cohort of 122 male individuals: a clinically stable opioid-dependent patient group receiving MMT (n = 48), an abstinent previously MMT maintained group (ABS) (n = 24) and healthy controls (n = 50). Stable MMT participants deliberated longer and placed higher bets earlier in the Cambridge Gambling Task (CGT) and showed impaired strategic planning compared with healthy controls. In contrast, ABS participants showed impairment in choosing the least likely outcome, delay aversion and risk adjustment on the CGT, and exhibited non-planning impulsivity compared with controls. MMT patients had widespread grey matter reductions in the orbitomedial prefrontal cortex, caudate, putamen and globus pallidus. In contrast, ABS participants showed midbrain-thalamic grey matter reductions. A higher methadone dose at the time of scanning was associated with a smaller globus pallidus in the MMT group. Our findings support an interpretation of heightened impulsivity in patients receiving MMT. Widespread structural brain abnormalities in the MMT group and reduced brain structural abnormality with abstinence suggest benefit of cessation of methadone intake. We suggest that a longitudinal study is required to determine whether abstinence improves abnormalities, or patients who achieve abstinence have reduced abnormalities before methadone cessation.

Source-Water Protection and Water-Quality Investigations in the Cambridge, Massachusetts, Drinking-Water Supply System

USGS Publications Warehouse

Waldron, Marcus C.; Norton, Chip; MacDonald, Timothy W.D.

1998-01-01

Introduction The Cambridge Water Department (CWD) supplies about 15 million gallons of water each day to more than 95,000 customers in the City of Cambridge, Massachusetts. Most of this water is obtained from a system of reservoirs located in Cambridge and in parts of five other suburban-Boston communities. The drainage basin that contributes water to these reservoirs includes several potential sources of drinking-water contaminants, including major highways, secondary roads, areas of commercial and industrial development, and suburban residential tracts. The CWD is implementing a comprehensive Source-Water Protection Plan to ensure that the highest quality water is delivered to the treatment plant. A key element of this plan is a program that combines systematic monitoring of the drainage basin with detailed investigations of the effects of nonpoint-source contaminants, such as highway-deicing chemicals, nutrients, oxygen-demanding organic compounds, bacteria, and trace metals arising from stormwater runoff. The U.S. Geological Survey (USGS) is working with the CWD and the Massachusetts Highway Department (MassHighway) to develop a better understanding of the sources, transport, and fate of many of these contaminants. This Fact Sheet describes source-water protection and water-quality investigations currently underway in the Cambridge drinking-water supply system. The investigations are designed to complement a national effort by the USGS to provide water suppliers and regulatory agencies with information on the vulnerability of water supplies and the movement and fate of source-water contaminants.

Buckling of structures; Proceedings of the Symposium, Harvard University, Cambridge, Mass., June 17-21, 1974

NASA Technical Reports Server (NTRS)

Budiansky, B.

1976-01-01

The papers deal with such topics as the buckling and post-buckling behavior of plates and shells; methods of calculating critical buckling and collapse loads; finite element representations for thin-shell instability analysis; theory and experiment in the creep buckling of plates and shells; creep instability of thick shell structures; analytical and numerical studies of the influence of initial imperfections on the elastic buckling of columns; mode interaction in stiffened panels under compression; imperfection-sensitivity in the interactive buckling of stiffened plates; buckling of stochastically imperfect structures; and the Liapunov stability of elastic dynamic systems. A special chapter is devoted to design problems, including the design of a Mars entry 'aeroshell', and buckling design in vehicle structures. Individual items are announced in this issue.

On the genus Cebrennus Simon, 1880 in Iran with description of a new species from Iranian Central Desert (Araneae: Sparassidae).

PubMed

Moradmand, Majid; Zamani, Alireza; Jäger, Peter

2016-06-08

The taxonomic knowledge on the desert-dwelling sparassid genus Cebrennus Simon, 1880 in Iran is updated by describing a new species, Cebrennus rambodjavani sp. nov. (male) from northern Qom in Iran's Central Desert, and reviewing the material of the previous Iranian record of the genus [sub C. kochi (O. Pickard-Cambridge, 1872)] from Bushehr, southern Iran, which is found to be a misidentification. A revised definition of the term "embolus kink", a male copulatory structure in Cebrennus, is given. A comparative discussion of this structure between several representatives of the genus Cebrennus is included.

Polymorphism in molecular solids: an extraordinary system of red, orange, and yellow crystals.

PubMed

Yu, Lian

2010-09-21

Diamond and graphite are polymorphs of each other: they have the same composition but different structures and properties. Many other substances exhibit polymorphism: inorganic and organic, natural and manmade. Polymorphs are encountered in studies of crystallization, phase transition, materials synthesis, and biomineralization and in the manufacture of specialty chemicals. Polymorphs can provide valuable insights into crystal packing and structure-property relationships. 5-Methyl-2-[(2-nitrophenyl)amino]-3-thiophenecarbonitrile, known as ROY for its red, orange, and yellow crystals, has seven polymorphs with solved structures, the largest number in the Cambridge Structural Database. First synthesized by medicinal chemists, ROY has attracted attention from solid-state chemists because it demonstrates the remarkable diversity possible in organic solids. Many structures of ROY polymorphs and their thermodynamic properties are known, making ROY an important model system for testing computational models. Though not the most polymorphic substance on record, ROY is extraordinary in that many of its polymorphs can crystallize simultaneously from the same liquid and are kinetically stable under the same conditions. Studies of ROY polymorphs have revealed a new crystallization mechanism that invalidates the common view that nucleation defines the polymorph of crystallization. A slow-nucleating polymorph can still dominate the product if it grows rapidly and nucleates on another polymorph. Studies of ROY have also helped understand a new, surprisingly fast mode of crystal growth in organic liquids cooled to the glass transition temperature. This growth mode exists only for those polymorphs that have more isotropic, and perhaps more liquid-like, packing. The rich polymorphism of ROY results from a combination of favorable thermodynamics and kinetics. Not only must there be many polymorphs of comparable energies or free energies, many polymorphs must be kinetically stable and crystallize at comparable rates to be observed. This system demonstrates the unique insights that polymorphism provides into solid-state structures and properties, as well as the inadequacy of our current understanding of the phenomenon. Despite many studies of ROY, it is still impossible to predict the next molecule that is equally or more polymorphic. ROY is a lucky gift from medicinal chemists.

Up the Garden Path: A Chemical Trail through the Cambridge University Botanic Garden

ERIC Educational Resources Information Center

Battle, Gary M.; Kyd, Gwenda O.; Groom, Colin R.; Allen, Frank H.; Day, Juliet; Upson, Timothy

2012-01-01

The living world is a rich source of chemicals with many medicines, dyes, flavorings, and foodstuffs having their origins in compounds produced by plants. We describe a chemical trail through the plant holdings of the Cambridge University Botanic Gardens. Visitors to the gardens are provided with a laminated trail guide with 22 stopping points…

Surface-water, water-quality, and meteorological data for the Cambridge, Massachusetts, drinking-water source area, water years 2007-08

USGS Publications Warehouse

Smith, Kirk P.

2011-01-01

Water samples were collected in nearly all of the subbasins in the Cambridge drinking-water source area and from Fresh Pond during the study period. Discrete water samples were collected during base-flow conditions with an antecedent dry period of at least 3 days. Composite sampl

Phillips Lab Project Manager’s Handbook

DTIC Science & Technology

1994-04-15

Phillips Lab continues to be the Air Force Phillips Laboratory (PL) center of excellence for space research and Kirtland AFB, New...POINTS OF CONTACT pages of world history. In 1949, the Cambridge Field Station was renamed the Kirtland AFB: Air Force Cambridge Research Laboratories ...by the Air Force’s facilities are geographically located. Phillips Laboratory at Kirtland Air Force

How Has Dewey's Democratic Theory Influenced the Development of a New Primary School? A Headteacher's Perspective

ERIC Educational Resources Information Center

Higham, Rupert; Biddulph, James

2018-01-01

This article provides the transcript of Dr. Rupert Higham (University College London, Institute of Education) in conversation with Dr. James Biddulph (Headteacher of the University of Cambridge Primary School). Among the topics discussed are: What the University of Cambridge Primary School (UCPS) motto, "Releasing the Imagination: Celebrating…

Old Glory and the Jolly Roger: The Cultural Constraints and Strategic Imperatives of Modern Piracy

DTIC Science & Technology

2009-06-01

41. Watkins , Eric. "Pirates Seize Another Tanker Off Yemen." Oil and Gas Journal (9 January 2009), http://www.ogj.com/display_article/352052/7...Piracy in the Graeco-Roman World. Cambridge: Cambridge University Press, 2002. Dobbins, James, Seth G. Jones, Keith Crane, and Beth Cole DeGrasse. The

[Cambridge Conference on School Mathematics Feasibility Studies 9-13.

ERIC Educational Resources Information Center

Cambridge Conference on School Mathematics, Newton, MA.

These materials are a part of a series of studies sponsored by the Cambridge Conference on School Mathematics which reflects the ideas of CCSM regarding the goals and objectives for school mathematics K-12. Feasibility Studies 9-13 contain a wide range of topics. The following are the titles and brief descriptions of these studies. Number…

Symmetry Motion Classes; Cambridge Conference on School Mathematics Feasibility Study No. 40.

ERIC Educational Resources Information Center

McLane, Lyn

These materials were written with the aim of reflecting the thinking of The Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. This document details the planning and response for each of ten lessons involving symmetry motions. The problems focused on (1) combining motions in a given order,…

Informal Geometry for Young Children; Cambridge Conference on School Mathematics; Feasibility Study No. 34b.

ERIC Educational Resources Information Center

Walter, Marion

These materials were written with the aim of reflecting the thinking of The Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. These materials are intended to provide children with a variety of informal activities in intuitive geometry in the elementary school. Opportunities are provided…

Inequalities and Real Numbers as a Basis for School Mathematics, Cambridge Conference on School Mathematics Feasibility Study No. 38.

ERIC Educational Resources Information Center

Lomon, Earle

These materials were developed as a practical response to some of the recommendations of the 1963 Cambridge Conference on School Mathematics (CCSM). Experimental sessions are described in detail in this report. In the Estabrook Elementary School, Lexington, Massachusetts, first grade children (1964-65 Academic Year) concentrated on material…

A FIRST STEP TOWARDS THE IMPLEMENTATION OF THE CAMBRIDGE MATHEMATICS CURRICULUM IN A K-12 UNGRADED SCHOOL.

ERIC Educational Resources Information Center

FOSTER, GARRETT R.

A SERIES OF THREE CONFERENCES WAS HELD TO EXPLORE THE FEASIBILITY OF IMPLEMENTING A LONG-RANGE CURRICULUM DEVELOPMENT PROJECT FOR AN UNGRADED, K-12 SCHOOL, BASED ON RECOMMENDATIONS OF THE CAMBRIDGE CONFERENCE ON SCHOOL MATHEMATICS. OVER 50 MATHEMATICIANS, MATHEMATICS EDUCATORS, AND PERSONS INVOLVED IN THEORETICAL AND APPLIED PSYCHOLOGICAL…

Probability Lessons at Hancock School, Lexington; Cambridge Conference on School Mathematics Feasibility Study No. 41.

ERIC Educational Resources Information Center

McLane, Lyn

These materials were written with the aim of reflecting the thinking of Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. Presented are plans for teaching 23 probability lessons in the elementary grades at Hancock School, Lexington, Massachusetts. The discovery approach was utilized by the…

Factors Affecting Applications to Oxford and Cambridge--Repeat Survey. Executive Summary with Statistics

ERIC Educational Resources Information Center

Ridley, Kate; White, Kerensa; Styles, Ben; Morrison, Jo

2005-01-01

This research follows up a study conducted in 1998 by the National Foundation for Educational Research (NFER) to investigate teachers' and students' views on the factors affecting students' choices of whether or not to apply to Oxford and Cambridge universities. It identifies what has changed since 1998 and areas in which the universities could…

University Choice: What Influences the Decisions of Academically Successful Post-16 Students?

ERIC Educational Resources Information Center

Whitehead, Joan M.; Raffan, John; Deaney, Rosemary

2006-01-01

The questionnaire survey reported in this paper is part of an ongoing evaluation of the effect of a bursary scheme on recruitment to Cambridge University. It sought to identify factors that encouraged or discouraged highly successful A Level students from applying to Cambridge. Findings reveal three main dimensions associated with the decision to…

Formal-Language-Theoretic Control & Coordination of Mobile Robots

DTIC Science & Technology

2007-10-29

and Applications, Cambridge, UK: Cambridge University Press, 1997. I. Chattopadhyay and A. Ray, ‘‘A complex measure for linear grammars ...under the leadership of Prof. Asok Ray and Dr. Ishanu Chattopadhyay, Pennsylvania State University , University Park, PA. This research project has...Investigator: Professor Asok Ray, Pennsylvania State University Key Contributor: Dr. Ishanu Chattopadhyay, Pennsylvania State University The

77 FR 9169 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-16

... on 8260-15A. The large number of SIAPs, Takeoff Minimums and ODPs, in addition to their complex... (GPS) Y RWY 20, Amdt 1B Cambridge, MN, Cambridge Muni, Takeoff Minimums and Obstacle DP, Orig Pipestone, MN, Pipestone Muni, NDB RWY 36, Amdt 7, CANCELLED Rushford, MN, Rushford Muni, Takeoff Minimums and...

The Target of the Question: A Taxonomy of Textual Features for Cambridge University "O" Levels English

ERIC Educational Resources Information Center

Benjamin, Shanti Isabelle

2015-01-01

This study investigates the typical textual features that are most frequently targeted in short-answer reading comprehension questions of the Cambridge University "O" Level English Paper 2. Test writers' awareness of how textual features impact on understanding of meanings in text decisions will determine to great extent their decisions…

The Key Political Decisions of the Military Government in Turkey, September 1980-November 1983 and the Impact on Those Decisions.

DTIC Science & Technology

1985-05-01

I-would argue that there is a relevant application of Professor Giovanni Sartoris theory of party systems to the Turkish case, especially in the 1979...1980 time frame. G. Sartori , Parties and Party Systems A Framework for Analysis (Cambridge Eng: Cambridge University Press, 1976). 7

Battle of Narratives

DTIC Science & Technology

2012-06-01

18 De Nooy, Wouter, Andrej Mrvar , and Vladimir Batagelj , Exploratory Social Network Analysis with Pajek (New York: Cambridge University Press, 2005... Mrvar , and Vladimir Batagelj . Exploratory Social Network Analysis with Pajek. New York: Cambridge University Press, 2005. Democratic National...Review 54(1):33-48; Brian Uzzi. 1996 . "The Sources and Consequences of Embeddedness for the Economic Performance of Organizations: The Network Effect

M-DCPS Student Performance in International Baccalaureate and Cambridge Advanced International Certificate of Education Programs. Research Brief. Volume 1102

ERIC Educational Resources Information Center

Blazer, Christie

2011-01-01

This Research Brief summarizes the performance of M-DCPS students participating in the International Baccalaureate (IB) and Cambridge Advanced International Certificate of Education (AICE) programs. Outcome data are provided for the eight M-DCPS schools offering the two programs and corresponding examinations. Participation in international…

76 FR 57713 - Wooden Bedroom Furniture From the People's Republic of China: Amended Final Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-09-16

... appearance on behalf of Liberty Furniture Industries Inc. (``Liberty'') on August 17, 2011. The law firm also... Department: (1) Left out the word ``Dongguan'' when it listed the entity ``Dongguan Cambridge Furniture Co., Ltd., Glory Oceanic Co., Ltd.'' (``Cambridge'') in the rate table of the Final Results; (2) did not...

Constructivism -- Is the United States Making China an Enemy?

DTIC Science & Technology

2012-03-12

theories to include critical theory , postmodernism, feminist theory , historical institutionalism, sociological institutionalism, symbolic...Alexander Wendt, Social Theory of International Politics (Cambridge: Cambridge University Press, 1999), 103. 2 Vendulka Kubalkova, Nicholas Onuf and Paul...Kowert, eds., International Relations in a Constructed World (Armonk, NY: M.E. Sharpe Inc., 1998), 59. 3 Wendt, Social Theory of International

Innovations and challenges in renal cancer: summary statement from the Third Cambridge Conference.

PubMed

Atkins, Michael B; Bukowski, Ronald M; Escudier, Bernard J; Figlin, Robert A; Hudes, Gary H; Kaelin, William G; Linehan, W Marston; McDermott, David F; Mier, James W; Pedrosa, Ivan; Rini, Brian I; Signoretti, Sabina; Sosman, Jeffrey A; Teh, Bin Tean; Wood, Christopher G; Zurita, Amado J; King, Laura

2009-05-15

The Third Cambridge Conference on Innovations and Challenges in Renal Cancer, a symposium held in Cambridge, Massachusetts, June 27-28, 2008, and chaired by Michael B. Atkins, was convened to discuss the current state of knowledge in the field, critique new data, stimulate communication among those involved in basic and clinical research, and offer recommendations for further study. Four main topics were discussed: genetics and molecular biology of renal cell cancer, staging and prognosis, systemic therapy, and correlative science and biomarkers in stage IV disease. The conference format combined brief presentations with extended periods of discussion. The conclusions and recommendations are summarized in this paper and presented in more detail in the individual papers that follow. (c) 2009 American Cancer Society.

Innovations and Challenges in Renal Cancer: Summary Statement From the Third Cambridge Conference

PubMed Central

Atkins, Michael B.; Bukowski, Ronald M.; Escudier, Bernard J.; Figlin, Robert A.; Hudes, Gary H.; Kaelin, William G.; Linehan, W. Marston; McDermott, David F.; Mier, James W.; Pedrosa, Ivan; Rini, Brian I.; Signoretti, Sabina; Sosman, Jeffrey A.; Teh, Bin Tean; Wood, Christopher G.; Zurita, Amado J.; King, Laura

2009-01-01

The Third Cambridge Conference on Innovations and Challenges in Renal Cancer, a symposium held in Cambridge, Massachusetts, June 27–28, 2008, and chaired by Michael B. Atkins, was convened to discuss the current state of knowledge in the field, critique new data, stimulate communication among those involved in basic and clinical research, and offer recommendations for further study. Four main topics were discussed: genetics and molecular biology of renal cell cancer, staging and prognosis, systemic therapy, and correlative science and biomarkers in stage IV disease. The conference format combined brief presentations with extended periods of discussion. The conclusions and recommendations are summarized in this paper and presented in more detail in the individual papers that follow. PMID:19402064

Cambridge Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Cambridge Elementary School, Cocoa, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Cambridge is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. Behind the children is Jim Thurston, a school volunteer and retired employee of USBI, who shared in the project. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

A Study of Supersonic Compression-Corner Interactions using Hybrid LES/RANS Models

DTIC Science & Technology

2014-01-20

Mach 2.5 shock / boundary layer interaction in a wind tunnel (experiments conducted at Cambridge University [15]) as a means of assessing methods... wind tunnel . The shock impinges upon the bottom surface of the wind tunnel , creating a region of shock -separated flow. The structure of the SBLI... waves into a shock wave (Figure 19, X = 0.1016 and X = 0.1278 stations) are also not well-predicted. The hot-wire measurements may not be as

The SME (Structure-Mapping Engine) User’s Manual (SME Version 2E)

DTIC Science & Technology

1988-12-30

It is prior to this step that one might want to think about wether to modify any system parameters (e.g., print the match hypotheses, print only the...Wshington, DC 20390 Department of Psychology Carnegie-Mellon University Dr. Judith Orsanu Schenley Park Dr. Harold P. O’Neil, Jr. Basic Research Office...Pinker Baltimore, MD 21201 Department of Psychology ElO-018 Dr. Judith W. Segal MIT Dr. J. Wesley Regian OERI Cambridge, MA 02139 AFHRL/IDI 556 New

Proceedings of the Image Understanding Workshop (18th) Held in Cambridge, Massachusetts on 6-8 April 1988. Volume 1

DTIC Science & Technology

1988-04-01

hypercube; methods, which work best in structured scenes, and parent/ child operations run in a smaller fixed time independent spatiotemporal energy...rectangle defines a new coordinate sVstem for it, image is constructed under orthographic projection. The child links that is relative to its own...that the child rectangle can shift in the X -- V plane, rectangle in the image. At first, a noiseless image is created relative to the nominal

Deterioration of Synthetic Fiber Rope during Marine Usage. Appendix A.

DTIC Science & Technology

1981-12-31

Rigidity, Moisture and Fibre Structure, JTI 48(6), T163-%174 (1957). R394 Khosla, N.K., Shrinkage Properties of Continuous Filament Yarns with Different...8217D-Ai3i 685 DETERIORATION OF SYNTHETIC FIBER ROPE DURING MARINE i/i USAGE APPENDIX AU) MASSACHUSETTS INST OF TECH CAMBRIDGE S BACKER ET AL. 31 DEC...79 70A -. - - DETERIORATION OF SYNTHETIC FIBER ROPE DURING MARINE USAGE -- APPNDIX A PROGRESS REPORT PROJECT R/T-11 PERIOD JANUARY 1 - DECEMBER 31

Solar and interplanetary dynamics; Proceedings of the Symposium, Harvard University, Cambridge, Mass., August 27-31, 1979

NASA Technical Reports Server (NTRS)

Dryer, M. (Editor); Tandberg-Hanssen, E.

1980-01-01

The symposium focuses on solar phenomena as the source of transient events propagating through the solar system, and theoretical and observational assessments of the dynamic processes involved in these events. The topics discussed include the life history of coronal structures and fields, coronal and interplanetary responses to long time scale phenomena, solar transient phenomena affecting the corona and interplanetary medium, coronal and interplanetary responses to short time scale phenomena, and future directions.

Travelling Wave Concepts for the Modeling and Control of Space Structures

DTIC Science & Technology

1988-01-31

ZIP Code) 77 Massachusetts Avenue AFOSR / L \\\\ 0 Cambridge, MA 02139 Bolling Air Force Base , DC 20332-6448 8a. NAME OF FUNDING/SPONSORING 8b OFFICE...FQ8671-88-00398 8c. ADDRESS (City, State, and ZIP Code) 10 SOURCE OF FUNDING NUMBERS Building 410 PROGRAM PROJECT tASK WORK UNIT Bolling Air Force Base ...at the Jet Propulsion Laboratories, and is writing two further papers for journal publication based on his PhD dissertation. In the winter of 1987

Enhancements to the NASA Astrophysics Science Information and Abstract Service

NASA Astrophysics Data System (ADS)

Kurtz, M. J.; Eichhorn, G.; Accomazzi, A.; Grant, C. S.; Murray, S. S.

1995-05-01

The NASA Astrophysics Data System Astrophysics Science Information and Abstract Service, the extension of the ADS Abstract Service continues rapidly to expand in both use and capabilities. Each month the service is used by about 4,000 different people, and returns about 1,000,000 pieces of bibliographic information. Among the recent additions to the system are: 1. Whole Text Access. In addition to the ApJ Letters we now have whole text for the ApJ on-line, soon we will have AJ and Rev. Mexicana. Discussions with other publishers are in progress. 2. Space Instrumentation Database. We now provide a second abstract service, covering papers related to space instruments. This is larger than the astronomy and astrophysics database in terms of total abstracts. 3. Reference Books and Historical Journals. We have begun putting the SAO Annals and the HCO Annals on-line. We have put the Handbook of Space Astronomy and Astrophysics by M.V. Zombeck (Cambridge U.P.) on-line. 4. Author Abstracts. We can now include original abstracts in addition to those we get from the NASA STI Abstracts Database. We have included abstracts for A&A in collaboration with the CDS in Strasbourg, and are collaborating with the AAS and the ASP on others. We invite publishers and editors of journals and conference proceedings to include their original abstracts in our service; send inquiries via e-mail to ads@cfa.harvard.edu. 5. Author Notes. We now accept notes and comments from authors of articles in our database. These are arbitrary html files and may contain pointers to other WWW documents, they are listed along with the abstracts, whole text, and data available in the index listing for every reference. The ASIAS is available at: http://adswww.harvard.edu/

Quantifying intermolecular interactions in solid state indapamide and other popular diuretic drugs: Insights from Hirshfeld surface study

NASA Astrophysics Data System (ADS)

Bojarska, Joanna; Fruziński, Andrzej; Maniukiewicz, Waldemar

2016-07-01

Hirshfeld surfaces (HS) and two-dimensional fingerprint plots are used to analyze the intermolecular interactions in indapamide and other popular thiazide diuretic derivatives. The crystal structure of indapamide (INDP) at 100 K determined by single-crystal X-ray analysis, is also reported. The title compound crystallizes in the centrosymmetric I2/a space group with one indapamide and half water molecule (lying on the glide plane) in the asymmetric unit. An interplay of N-H⋯O hydrogen bonds connects the indapamide molecules generating chains with the graph-set motifs: C (8) and C23 (16), and together with C-H⋯O and π⋯π stacking interactions create a 3D net. The Hirshfeld surface study facilitates comparison of diverse and numerous intercontacts, such as H⋯H, O⋯H, Cl⋯H, C⋯C (π⋯π), C⋯O (π⋯lone pair), O⋯O (lone pair⋯lone pair), Cl⋯O, Cl⋯Cl, N⋯N, C⋯H (C-H⋯π) with regard to building self-assembled framework of indapamide and related thiazide derivatives retrieved from the Cambridge Structural Database. The HS analysis highlights that H⋯H, O⋯H/H⋯O and C⋯H/H⋯C contacts play an influential role contributing to about 80% of the HS areas in this class of compounds. Nevertheless, in the case of INDP the H⋯H interactions, while in hydrochlorothiazide (HCTZ) O⋯H/H⋯O are dominant amongst all intercontacts towards the HS. Notably, indapamide has the highest proportion of C⋯C contacts.

In Living Memory: The Dying Art of Learning Poetry and a Case for Revival

ERIC Educational Resources Information Center

Pullinger, Debbie

2012-01-01

This article considers the practice of learning poems and the value of poetry in the memory, and emerges from the Cambridge Poetry Teaching Project, a small-scale research study co-ordinated through the Faculty of Education at the University of Cambridge. Drawing on the subset of findings in relation to learning and memory, the essay locates the…

Goals for Mathematical Education of Elementary School Teachers: A Report of the Cambridge Conference on Teacher Training.

ERIC Educational Resources Information Center

Education Development Center, Inc., Newton, MA.

This report is intended to provide attention to issues that the Cambridge Conference feels are related to the mathematical training of elementary school teachers. The document is divided into three parts. Part I, titled "The Problems and Proposals Towards the Solution," contains the following chapters: (1) Introduction to the Report; (2)…

An Experimental Text in Transformational Geometry, Student Text; Cambridge Conference on School Mathematics Feasibility Study No. 43a.

ERIC Educational Resources Information Center

Cambridge Conference on School Mathematics, Newton, MA.

This is part of a student text which was written with the aim of reflecting the thinking of The Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for mathematics. The instructional materials were developed for teaching geometry in the secondary schools. This document is chapter six and titled Motions and…

[Geometry Through Symmetry, Cambridge Conference on School Mathematics Feasibility Study No. 32.

ERIC Educational Resources Information Center

Friedman, Bernard

These materials were written for the use of a class of eighth grade high ability students in a four week course sponsored by Educational Services Incorporated on the Stanford campus. They represent a practical response to the proposal by the Cambridge Conference of 1963 that geometry be taught by vector space methods. Instead of using vector…

Inequality Lessons at Adams School, Lexington; Cambridge Conference on School Mathematics Feasibility Study No. 42.

ERIC Educational Resources Information Center

Fitzgerald, B.

These materials were written with the aim of reflecting the thinking of The Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics. Presented are plans for teaching 15 inequality lessons for above average first grade students. The discovery approach is utilized by the teacher in order to involve…

A Flexible Approach to Quantifying Various Dimensions of Environmental Complexity

DTIC Science & Technology

2004-08-01

dissertation, Cambridge University, Cambridge, England, 1989. [15] C. J. C. H. Watkins and P. Dayan, “Q-learning,” Machine Learning , vol. 8, pp. 279–292, 1992...16] I. Szita, B. Takács, and A. Lörincz, “²-MDPs: Learning in varying environments,” Journal of Machine Learning Research, vol. 3, pp. 145–174, 2002

Problem Articulation and the Processes of Assistance: An Activity Theoretic View of Mediation in Game Play

ERIC Educational Resources Information Center

Stone, Lynda D.; Gutierrez, Kris D.

2007-01-01

In this article, we study a local adaptation of the Fifth Dimension [Cole, M. (1996). "Cultural psychology: A once and future discipline." Cambridge: Cambridge University Press] known as Las Redes (i.e., Networks of Collaboration in the Fifth Dimension) to examine how the multiple activity systems of Las Redes, e.g. the undergraduate course and…

"Please Do Not Leave Any Notes for the Cleaning Lady, as Many Do Not Speak English Fluently": Policy, Power, and Language Brokering in a Multilingual Workplace

ERIC Educational Resources Information Center

Gonçalves, Kellie; Schluter, Anne

2017-01-01

This article investigates the covert language policy and micro-language planning practices of one female Brazilian-American entrepreneur, Magda, within her multilingual cleaning company. Because Magda is plurilingual (Spolsky in "Language policy." Cambridge University Press, Cambridge, 2004), she is able to draw on her metalinguistic…

Satisficing Decision-Making in Supervisory Control. Part 2.

DTIC Science & Technology

1986-07-31

purpose of the United States Government. C-P Department of Mechanical Engineering Massachusetts Institute of Technology Cambridge, Massachusetts 02139...of Mechanical Engineering Massachusetts Institute of Technology Cambridge MA 02139 Satisficing Decision-Making in Supervisory Control Leonid Charny...example, that there are two attributes, speed and accuracy, and one is selecting a robot manipulator based -4n these two parameters. A set of alternatives

The Cambridge Primary Review: A Reply to R. J. Campbell

ERIC Educational Resources Information Center

Armstrong, Michael

2010-01-01

The author was disappointed by R. J. Campbell's sour critique of the Cambridge Primary Review in "FORUM" Volume 52 Number 1 2010. His description of the Review's proposals on curriculum and pedagogy as "backward-looking, cumbersome and partial" is such a bizarre misjudgement that it calls for some response. The author comments in turn on R. J.…

Robot Programming.

DTIC Science & Technology

1982-12-01

Paris, France, June, 1982, 519-530. Latoinbe, J. C. "Equipe Intelligence Artificielle et Robotique: Etat d’avancement des recherches," Laboratoire...8217AD-A127 233 ROBOT PROGRRMMING(U) MASSACHUSETTS INST OFGTECHi/ CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB T LOZANO-PEREZ UNCLASSIFIED DC8 AI-9 N884...NAME AND ADDRESS 10. PROGRAM ELEMENT. PROJECT. TASK Artificial Intelligence Laboratory AREA I WORK UNIT NUMBERS ,. 545 Technology Square Cambridge

Mantle convection and the distribution of geochemical reservoirs in the silicate shell of the Earth

NASA Astrophysics Data System (ADS)

Walzer, Uwe; Hendel, Roland

2010-05-01

We present a dynamic 3-D spherical-shell model of mantle convection and the evolution of the chemical reservoirs of the Earth`s silicate shell. Chemical differentiation, convection, stirring and thermal evolution constitute an inseparable dynamic system. Our model is based on the solution of the balance equations of mass, momentum, energy, angular momentum, and four sums of the number of atoms of the pairs 238U-206Pb, 235U-207Pb, 232Th-208Pb, and 40K-40Ar. Similar to the present model, the continental crust of the real Earth was not produced entirely at the start of the evolution but developed episodically in batches [1-7]. The details of the continental distribution of the model are largely stochastic, but the spectral properties are quite similar to the present real Earth. The calculated Figures reveal that the modeled present-day mantle has no chemical stratification but we find a marble-cake structure. If we compare the observational results of the present-day proportion of depleted MORB mantle with the model then we find a similar order of magnitude. The MORB source dominates under the lithosphere. In our model, there are nowhere pure unblended reservoirs in the mantle. It is, however, remarkable that, in spite of 4500 Ma of solid-state mantle convection, certain strong concentrations of distributed chemical reservoirs continue to persist in certain volumes, although without sharp abundance boundaries. We deal with the question of predictable and stochastic portions of the phenomena. Although the convective flow patterns and the chemical differentiation of oceanic plateaus are coupled, the evolution of time-dependent Rayleigh number, Rat , is relatively well predictable and the stochastic parts of the Rat(t)-curves are small. Regarding the juvenile growth rates of the total mass of the continents, predictions are possible only in the first epoch of the evolution. Later on, the distribution of the continental-growth episodes is increasingly stochastic. Independently of the varying individual runs, our model shows that the total mass of the present-day continents is not generated in a single process at the beginning of the thermal evolution of the Earth but in episodically distributed processes in the course of geological time. This is in accord with observation. Finally, we present results regarding the numerical method, implementation, scalability and performance. References [1] Condie, K. C., Episodie continental growth models: Afterthoughts and extensions, Tectonophysics, 322 (2000), 153-162. [2] Davidson, J. P. and Arculus, R. J., The significance of Phanerozoic arc magmatism in generating continental crust, in Evolution and Differentiation of the Continental Crust, edited by M. Brown and T. Rushmer (2006), 135-172, Cambridge Univ. Press, Cambridge, UK. [3] Hofmann, A. W., Sampling mantle heterogeneity through oceanic basalts: Isotopes and trace elements, in Treatise on Geochemistry, Vol. 2: The Mantle and the Core, edited by R. W. Carlson (2003), 61-101, Elsevier, Amsterdam. [4] Rollinson, H., Crustal generation in the Archean, in Evolution and Differentiation of the Continental Crust, edited by M. Brown and T. Rushmer (2006), 173-230, Cambridge Univ. Press, Cambridge, UK: [5] Taylor, S. R. and McLennan, S. M., Planetary Crusts. Their Composition, Origin and Evolution. (2009), 1-378, Cambridge Univ. Press, Cambridge, UK. [6] Walzer, U. and Hendel, R., Mantle convection and evolution with growing continents. J. Geophys. Res. 113 (2008), B09405, doi: 10.1029/2007JB005459 [7] http://www.igw.uni-jena.de/geodyn

Quantum simulation of transverse Ising models with Rydberg atoms

NASA Astrophysics Data System (ADS)

Schauss, Peter

2018-04-01

Quantum Ising models are canonical models for the study of quantum phase transitions (Sachdev 1999 Quantum Phase Transitions (Cambridge: Cambridge University Press)) and are the underlying concept for many analogue quantum computing and quantum annealing ideas (Tanaka et al Quantum Spin Glasses, Annealing and Computation (Cambridge: Cambridge University Press)). Here we focus on the implementation of finite-range interacting Ising spin models, which are barely tractable numerically. Recent experiments with cold atoms have reached the interaction-dominated regime in quantum Ising magnets via optical coupling of trapped neutral atoms to Rydberg states. This approach allows for the tunability of all relevant terms in an Ising spin Hamiltonian with 1/{r}6 interactions in transverse and longitudinal fields. This review summarizes the recent progress of these implementations in Rydberg lattices with site-resolved detection. Strong correlations in quantum Ising models have been observed in several experiments, starting from a single excitation in the superatom regime up to the point of crystallization. The rapid progress in this field makes spin systems based on Rydberg atoms a promising platform for quantum simulation because of the unmatched flexibility and strength of interactions combined with high control and good isolation from the environment.

Development of the Fray-Farthing-Chen Cambridge Process: Towards the Sustainable Production of Titanium and Its Alloys

NASA Astrophysics Data System (ADS)

Hu, Di; Dolganov, Aleksei; Ma, Mingchan; Bhattacharya, Biyash; Bishop, Matthew T.; Chen, George Z.

2018-02-01

The Kroll process has been employed for titanium extraction since the 1950s. It is a labour and energy intensive multi-step semi-batch process. The post-extraction processes for making the raw titanium into alloys and products are also excessive, including multiple remelting steps. Invented in the late 1990s, the Fray-Farthing-Chen (FFC) Cambridge process extracts titanium from solid oxides at lower energy consumption via electrochemical reduction in molten salts. Its ability to produce alloys and powders, while retaining the cathode shape also promises energy and material efficient manufacturing. Focusing on titanium and its alloys, this article reviews the recent development of the FFC-Cambridge process in two aspects, (1) resource and process sustainability and (2) advanced post-extraction processing.

Smooth- and rough-wall boundary layer structure from high spatial range particle image velocimetry

NASA Astrophysics Data System (ADS)

Squire, D. T.; Morrill-Winter, C.; Hutchins, N.; Marusic, I.; Schultz, M. P.; Klewicki, J. C.

2016-10-01

Two particle image velocimetry arrangements are used to make true spatial comparisons between smooth- and rough-wall boundary layers at high Reynolds numbers across a very wide range of streamwise scales. Together, the arrangements resolve scales ranging from motions on the order of the Kolmogorov microscale to those longer than twice the boundary layer thickness. The rough-wall experiments were obtained above a continuous sandpaper sheet, identical to that used by Squire et al. [J. Fluid Mech. 795, 210 (2016), 10.1017/jfm.2016.196], and cover a range of friction and equivalent sand-grain roughness Reynolds numbers (12 000 ≲δ+≲ 18000, 62 ≲ks+≲104 ). The smooth-wall experiments comprise new and previously published data spanning 6500 ≲δ+≲17 000 . Flow statistics from all experiments show similar Reynolds number trends and behaviors to recent, well-resolved hot-wire anemometry measurements above the same rough surface. Comparisons, at matched δ+, between smooth- and rough-wall two-point correlation maps and two-point magnitude-squared coherence maps demonstrate that spatially the outer region of the boundary layer is the same between the two flows. This is apparently true even at wall-normal locations where the total (inner-normalized) energy differs between the smooth and rough wall. Generally, the present results provide strong support for Townsend's [The Structure of Turbulent Shear Flow (Cambridge University Press, Cambridge, 1956), Vol. 1] wall-similarity hypothesis in high Reynolds number fully rough boundary layer flows.

Arbitrary amplitude electrostatic wave propagation in a magnetized dense plasma containing helium ions and degenerate electrons

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

Mahmood, S., E-mail: shahzadm100@gmail.com; Sadiq, Safeer; Haque, Q.

2016-06-15

The obliquely propagating arbitrary amplitude electrostatic wave is studied in a dense magnetized plasma having singly and doubly charged helium ions with nonrelativistic and ultrarelativistic degenerate electrons pressures. The Fermi temperature for ultrarelativistic degenerate electrons described by N. M. Vernet [(Cambridge University Press, Cambridge, 2007), p. 57] is used to define ion acoustic speed in ultra-dense plasmas. The pseudo-potential approach is used to solve the fully nonlinear set of dynamic equations for obliquely propagating electrostatic waves in a dense magnetized plasma containing helium ions. The upper and lower Mach number ranges for the existence of electrostatic solitons are found whichmore » depends on the obliqueness of the wave propagation with respect to applied magnetic field and charge number of the helium ions. It is found that only compressive (hump) soliton structures are formed in all the cases and only subsonic solitons are formed for a singly charged helium ions plasma case with nonrelativistic degenerate electrons. Both subsonic and supersonic soliton hump structures are formed for doubly charged helium ions with nonrelativistic degenerate electrons and ultrarelativistic degenerate electrons plasma case containing singly as well as doubly charged helium ions. The effect of propagation direction on the soliton amplitude and width of the electrostatic waves is also presented. The numerical plots are also shown for illustration using dense plasma parameters of a compact star (white dwarf) from literature.« less

Fine refinement of solid state structure of racemic form of phospho-tyrosine employing NMR Crystallography approach.

PubMed

Paluch, Piotr; Pawlak, Tomasz; Oszajca, Marcin; Lasocha, Wieslaw; Potrzebowski, Marek J

2015-02-01

We present step by step facets important in NMR Crystallography strategy employing O-phospho-dl-tyrosine as model sample. The significance of three major techniques being components of this approach: solid state NMR (SS NMR), X-ray diffraction of powdered sample (PXRD) and theoretical calculations (Gauge Invariant Projector Augmented Wave; GIPAW) is discussed. Each experimental technique provides different set of structural constraints. From the PXRD measurement the size of the unit cell, space group and roughly refined molecular structure are established. SS NMR provides information about content of crystallographic asymmetric unit, local geometry, molecular motion in the crystal lattice and hydrogen bonding pattern. GIPAW calculations are employed for validation of quality of elucidation and fine refinement of structure. Crystal and molecular structure of O-phospho-dl-tyrosine solved by NMR Crystallography is deposited at Cambridge Crystallographic Data Center under number CCDC 1005924. Copyright © 2014 Elsevier Inc. All rights reserved.

Dynamics of δ-dopant redistribution during heterostructure growth

NASA Astrophysics Data System (ADS)

Pankratov, E. L.

2007-06-01

It has recently been shown that growth of a multilayer structure with one or more delta-layers at high temperature leads to spreading and asymmetrization of the dopant distribution [see, for example, E.F.J. Schubert, Vac. Sci. Technol. A. 8, 2980 (1990), A.M. Nazmul, S. Sugahara, M. Tanaka, J. Crystal Growth 251, 303 (2003); R.C. Newman, M.J. Ashwin, M.R. Fahy, L. Hart, S.N. Holmes, C. Roberts, X. Zhang, Phys. Rev. B 54, 8769 (1996); E.F. Schubert, J.M. Kuo, R.F. Kopf, H.S. Luftman, L.C. Hopkins, N.J. Sauer, J. Appl. Phys. 67, 1969 (1990); P.M. Zagwijn, J.F. van der Veen, E. Vlieg, A.H. Reader, D.J. Gravesteijn, J. Appl. Phys. 78, 4933 (1995); W.S. Hobson, S.J. Pearton, E.F. Schubert, G. Cabaniss, Appl. Phys. Lett. 55, 1546 (1989); Delta Doping of Semiconductors, edited by E.F. Schubert (Cambridge University Press, Cambridge, 1996); Yu.N. Drozdov, N.B. Baidus', B.N. Zvonkov, M.N. Drozdov, O.I. Khrykin, V.I. Shashkin, Semiconductors 37, 194 (2003); E. Skuras, A.R. Long, B. Vogele, M.C. Holland, C.R. Stanley, E.A. Johnson, M. van der Burgt, H. Yaguchi, J. Singleton, Phys. Rev. B 59, 10712 (1999); G. Li, C. Jagadish, Solid-State Electronics 41, 1207 (1997)]. In this work analytical and numerical analysis of dopant dynamics in a delta-doped area of a multilayer structure has been accomplished using Fick's second law. Some reasons for asymmetrization of a delta-dopant distribution are illustrated. The spreading of a delta-layer has been estimated using example materials of a multilayer structure, a delta-layer and an overlayer.

Windows of Opportunity: East Timor and Australian Strategic Decision Making (1975-1999)

DTIC Science & Technology

2014-06-01

could not be further from the truth. Australia has always been consistent, adjusting its foreign policy to take advantage of shifting international ... International Security. Cambridge; New York: Cambridge University Press, 2003. Carey, P. B. R, and G. Carter Bentley. East Timor at the Crossroads: The...DISTRIBUTION A. Approved for public release: distribution unlimited. WINDOWS OF OPPORTUNITY: EAST TIMOR AND AUSTRALIAN STRATEGIC DECISION

Undergraduate-postgraduate astronomy in Cambridge - a student's perspective

NASA Astrophysics Data System (ADS)

Williams, Robin

1991-01-01

This article describes the astronomical scene at Cambridge University from the point of view of a one-time graduate there: I'm now a first-year postgraduate. I progressed from an interest in Maths and Physics at sixth-form level to a degree in Physics and Theoretical Physics, a postgraduate Applied Maths and Theoretical Physics course (Part III) and now to the Institute of Astronomy.

Use of a Photosimulation Laboratory for Estimating Vehicle Detection Probability and Comparing Detection Metrics

DTIC Science & Technology

2003-04-15

the monitors, the authors are confident that the color fidelity is accurate. The primary physical difference of field versus lab tests is the level... Creelman , C. Douglas, Detection theory: A user’s guide, Cambridge University Press, Cambridge, U.K., 1991, pp. 189-190. *For more information, contact Dr. Thomas Meitzler at (586) 574-5405, email: meitzlet@tacom.army.mil

Provisional Approaches to Goals for School Mathematics; Cambridge Conference on School Mathematics Feasibility Study No. 37.

ERIC Educational Resources Information Center

Cambridge Conference on School Mathematics, Newton, MA.

These materials were written with the aim of reflecting the thinking of Cambridge Conference on School Mathematics (CCSM) regarding the goals and objectives for school mathematics K-6. In view of the experiences of other curriculum groups and of the general discussions since 1963, the present report initiates the next step in evolving the "Goals".…

Trajectories of Offending and Their Relation to Life Failure in Late Middle Age: Findings from the Cambridge Study in Delinquent Development

ERIC Educational Resources Information Center

Piquero, Alex R.; Farrington, David P.; Nagin, Daniel S.; Moffitt, Terrie E.

2010-01-01

Researchers have hypothesized that over the life course, criminal offending varies with problems in other domains, including life failure and physical and mental health. To examine this issue, the authors use data from the Cambridge Study in Delinquent Development, a prospective longitudinal survey of 411 South London males first studied at age 8…

Preparing for College Success: Exploring the Impact of the High School Cambridge Acceleration Program on U.S. University Students

ERIC Educational Resources Information Center

Shaw, Stuart D.; Werno, Magda A.

2016-01-01

This case study sought to gain a better understanding of the impact of the Cambridge Acceleration Program on students' transition from high school to college at one American university. The findings from an online questionnaire indicate that many participants develop a range of skills that are perceived as important in the context of university…

Classification of Complex Sounds.

DTIC Science & Technology

1992-10-31

spectral weights may be useful in developing signal enhancement techniques based on psychological aspects of the listener (providing a complement to...Journals) Green, D.M., and Berg, B.G. (1991). Spectral weights and the profile bowl. Quarterly Journal of Experimental Psychology , 43A, 449-458. Dai, H...Macmillan and C.D. Creelman . Cambridge/NY: Cambridge Universi- ty Press, 1991.) J. Math. Psych., in press. Training Currently, there are two graduate

Beaches of the Future: Analyzing Territorial Disputes in South America

DTIC Science & Technology

2016-09-01

Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork...in the Twentieth Century (Cambridge: Cambridge University Press, 2002), 16. 28 Ibid. 11 realist approach that finds leaders concurrently managing ...United Kingdom107 Alternatively, these arbitration treaties managed to cool tensions between the Argentina and Chile, two stockpiling players involved

COmmunications and Networking with QUantum Operationally-Secure Technology for Maritime Deployment (CONQUEST)

DTIC Science & Technology

2017-03-06

Raytheon BBN Technologies ; Dr. Saikat Guha Contractor Address: 10 Moulton Street, Cambridge, MA 02138 Title of the Project : COmmunications and...BBN Technologies 10 Moulton Street Cambridge, MA 02138 6 March 2017 US Navy Office of Naval Research One Liberty Center 875 North Randolph...Networking with QUantum operationally-Secure Technology for Maritime Deployment (CONQUEST) Contract Period of Performance: 2 September 2016 – 1

Generic Software for Emulating Multiprocessor Architectures.

DTIC Science & Technology

1985-05-01

RD-A157 662 GENERIC SOFTWARE FOR EMULATING MULTIPROCESSOR 1/2 AlRCHITECTURES(J) MASSACHUSETTS INST OF TECH CAMBRIDGE U LRS LAB FOR COMPUTER SCIENCE R...AREA & WORK UNIT NUMBERS MIT Laboratory for Computer Science 545 Technology Square Cambridge, MA 02139 ____________ I I. CONTROLLING OFFICE NAME AND...aide If neceeasy end Identify by block number) Computer architecture, emulation, simulation, dataf low 20. ABSTRACT (Continue an reverse slde It

Intelligence Collection Targeting and Interdiction of Dark Networks

DTIC Science & Technology

2014-06-01

2006): 346. 26 Wouter de Nooy, Andrej Mrvar , and Vladimir Batagelj . Exploratory Social Network Analysis with Pajek, 2nd ed. (Cambridge: Cambridge...Pittsburgh, PA: Carnegie Mellon University, 2013. de Nooy, Wouter, Andrej Mrvar , and Vladimir Batagelj . Exploratory Social Network Analysis with...al-Qaeda’s leaders had closely followed the April 1996 assassination of Dzhokhar Dudayev, the Chechen prime minister, who was killed by a Russian

Investigation of Elliptical Cooling Channels for a Naval Electromagnetic Railgun

DTIC Science & Technology

2005-05-09

Numerical Recipes in C : The Art of Scientific Computing, Second Edition. Cambridge: Cambridge University Press, 1992. Ramanujan , S. Ramanujan’s...by Midshipman 1/ c Elizabeth R. Kealey, Class of 2005 United States Naval Academy Annapolis, MD ___________________________________ (signature...system 55 10 Equation 46: Fourier number 55 Equation 47: General heat equation with coefficients a, b, c , and d 55 Equation 48: Tridiagonal matrix

Assisting Design Given Multiple Performance Criteria

DTIC Science & Technology

1988-08-01

with uninstantiated operators is created then each operator’s implementation is selected. g - Keywords: computer-aided design, artificial...IEEE Trans- actions on Software Engineering, SE-7(1), 1981. [BG86] Forrest D. Brewer and Daniel D. Gajski . An expert-system paradigm for de- sign. In...Teukolsky, api William T. Vet- terling. Numerical Recipes. Cambridge University Press, Cambridge, England, 1987. [RFS83] G . G . Rassweiler, M. D

Fiber optic and laser sensors IV; Proceedings of the Meeting, Cambridge, MA, Sept. 22-24, 1986

NASA Technical Reports Server (NTRS)

De Paula, Ramon P. (Editor); Udd, Eric (Editor)

1987-01-01

The conference presents papers on industrial uses of fiber optic sensors, point and distributed polarimetric optical fiber sensors, fiber optic electric field sensor technology, micromachined resonant structures, single-mode fibers for sensing applications, and measurement techniques for magnetic field gradient detection. Consideration is also given to electric field meter and temperature measurement techniques for the power industry, the calibration of high-temperature fiber-optic microbend pressure transducers, and interferometric sensors for dc measurands. Other topics include the recognition of colors and collision avoidance in robotics using optical fiber sensors, the loss compensation of intensity-modulating fiber-optic sensors, and an embedded optical fiber strain tensor for composite structure applications.

Investigation of Prolific Sheep from UK and Ireland for Evidence on Origin of the Mutations in BMP15 (FecXG, FecXB) and GDF9 (FecGH) in Belclare and Cambridge Sheep

PubMed Central

Mullen, Michael P.; Hanrahan, James P.; Howard, Dawn J.

2013-01-01

This paper concerns the likely origin of three mutations with large effects on ovulation rate identified in the Belclare and Cambridge sheep breeds; two in the BMP15 gene (FecXG and FecXB) and the third (FecGH) in GDF9. All three mutations segregate in Belclare sheep while one, FecXB, has not been found in the Cambridge. Both Belclare and Cambridge breeds are relatively recently developed composites that have common ancestry through the use of genetic material from the Finnish Landrace and Lleyn breeds. The development of both composites also involved major contributions from exceptionally prolific ewes screened from flocks in Ireland (Belclare) and Britain (Cambridge) during the 1960s. The objective of the current study was to establish the likely origin of the mutations (FecXG, FecXB and FecGH) through analysis of DNA from Finnish Landrace and Lleyn sheep, and Galway and Texel breeds which contributed to the development of the Belclare breed. Ewes with exceptionally high prolificacy (hyper-prolific ewes) in current flocks on Irish farms were identified to simulate the screening of ewes from Irish flocks in the 1960s. DNA was obtained from: prolific ewes in extant flocks of Lleyn sheep (n = 44) on the Lleyn peninsula in Wales; hyper-prolific ewes (n = 41); prolific Galway (n = 41) ewes; Finnish Landrace (n = 124) and Texel (n = 19) ewes. The FecXG mutation was identified in Lleyn but not in Finnish Landrace, Galway or Texel sheep; FecXB was only found among the hyper-prolific ewes. The FecGH mutation was identified in the sample of Lleyn sheep. It was concluded from these findings that the Lleyn breed was the most likely source of the FecXG and FecGH mutations in Belclare and Cambridge sheep and that the FecXB mutation came from the High Fertility line that was developed using prolific ewes selected from commercial flocks in Ireland in the 1960′s and subsequently used in the genesis of the Belclare. PMID:23301039

Physical Causation. Phil Dowe, Physical causation (Cambridge Studies in Probability, Induction, and Decision Theory), Cambridge University Press, Cambridge, 2000, pp. ix+224, price US60.00, ISBN: 0-521-78049-7 hbk

NASA Astrophysics Data System (ADS)

Hausman, Daniel M.

Causation is a frustrating subject. Suppose one begins with some promising idea such as that causation is counterfactual dependence or statistical relevance. One then develops this idea with care and intelligence, revises and improves it to cope with criticisms, and by the time one is finished, sane people will be looking elsewhere. If one wants conclusive reasons to reject the counterfactual theory of causation, one can do no better than to read Lewis' (1986) many postscripts. If one wants the best refutation of a probabilistic theory of causation, then one should read my colleague, Ellery Eells' (1991) magisterial defense. In Physical Causation, Phil Dowe performs the same service for physical process/interaction theories of causation.

In America’s Wake: A Comparison of Rising Power Foreign Policies

DTIC Science & Technology

2016-06-01

judgments or pronouncements as to the propriety or impropriety of any particular course of action. The author is unconvinced that ex post facto ...Expansion, 3rd ed, Cambridge Imperial and Post -Colonial Studies Series (Houndmills, Basingstoke, Hampshire ; New York: Palgrave/Macmillan, 2002), 14...Century, 1815-1914: A Study of Empire and Expansion, 3rd ed, Cambridge Imperial and Post -Colonial Studies Series (Houndmills, Basingstoke, Hampshire

Motion Simulation in the Environment for Auditory Research

DTIC Science & Technology

2011-08-01

Toolbox, Centre for Digital Music , Queen Mary University of London, 2009. http://www.isophonics.net/content/spatial-audio- matlab-toolbox (accessed July 27...this work. 46 Student Bio I studied Music Technology at Northwestern University, graduating as valedictorian of the School of... Music in 2008. In 2009, I was awarded the Gates Cambridge Scholarship to fund a postgraduate degree at the University of Cambridge. I read for a

Goals for the Correlation of Elementary Science and Mathematics; The Report of the Cambridge Conference on the Correlation of Science and Mathematics in Schools.

ERIC Educational Resources Information Center

Cambridge Conference on School Mathematics, Newton, MA.

This is The Report of the 1967 Cambridge Conference on the Correlation of Science and Mathematics in the Schools. It is addressed to professionals in education, and is designed to stimulate dialogue among them concerning the mathematics-science curriculum. The report is organized in five chapters, each dealing respectively with (1) educational…

Computing Environments for Data Analysis. Part 3. Programming Environments.

DTIC Science & Technology

1986-05-21

to understand how the existing system works and how to modify them to get the desired effect. This depends on the programming ...editor that performs automatic syntax checking for all the programming languages. 3.3 How S fits in To make efficient use of the machine (maximize the... programming , manuscript from Symbolics, Inc., 5 Cambridge Center, Cambridge, Mass. 02142. [101 DEITEL H.M., (1983) An Introduction to Operating

Sensing Strategies for Disambiguating among Multiple Objects in Known Poses.

DTIC Science & Technology

1985-08-01

ELEMENT. PROIECT. TASK Artificial Inteligence Laboratory AE OKUI UBR 545 Technology Square Cambridge, MA 021.39 11. CONTROLLING OFFICE NAME AND ADDRESS 12...AD-Ali65 912 SENSING STRATEGIES FOR DISAMBIGURTING MONG MULTIPLE 1/1 OBJECTS IN KNOWN POSES(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL ...or Dist Special 1 ’ MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A. I. Memo 855 August, 1985 Sensing Strategies for

Herbert: A Second Generation Mobile Robot.

DTIC Science & Technology

1988-01-01

PROJECT. TASK S Artificial Inteligence Laboratory AREA A WORK UNIT NUMBERS ’ ~ 545 Technology Square Cambridge, MA 02139 11. CONTROLLING OFFICE NAME...AD-AI93 632 WMRT: A SECOND GENERTION MOBILE ROWT(U) / MASSACHUSETTS IMST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB R BROOKS ET AL .JAN l8 Al-M...MASSACHUSETTS INSTITUTE OF TECHNOLOGY ARTIFICIAL INTELLIGENCE LABORATORY A. I. Memo 1016 January, 1988 HERBERT: A SECOND GENERATION MOBILE ROBOT Rodney A

Content Questions In American Sign Language: An RRG Analysis

DTIC Science & Technology

2004-12-08

a temporal framework, someone might sign (29) DURING FIVE YEAR YONDER GALLAUDET … During my five years at Gallaudet …. Until a new topic is...Language: A Teacher’s Resource on Grammar and Culture. Washington, D.C.: Gallaudet University Press. BATTISON, ROBBIN. 1978. Loan Signs from...Typology and Syntactic Description, ed. by Timothy Shopen. Cambridge, MA: Cambridge University Press. —. In press b. Clause Types. Language Typology

Self-Stabilizing and Efficient Robust Uncertainty Management

DTIC Science & Technology

2011-10-01

Group decision making in honey bee swarms. American Scientist. 94:220-229. 71 Frisch, Karl von. (1967) The Dance Language and Orientation of... Bees . Cambridge, Mass.: The Belknap Press of Harvard University Press. 18 Thom et al. (21 August 2007) The Scent of the Waggle Dance . PLoS Biology...Orientation of Bees . Cambridge, Mass.: The Belknap Press of Harvard University Press. 02 Frisch, Karl von. (1967) The Dance Language and

Civil Wars in Britain, 1640-1646 Military Revolution on Campaign

DTIC Science & Technology

2001-01-01

revolution thesis. In the 1980s David Parrott argued that the tactical reforms described by Roberts were in practice nearly irrelevant to the battles...Social Order: Reading and Writing in Tudor and Stuart England (Cambridge: Cambridge University Press, 1980 ), passim. 8A royal license was obtained by...Finlayson, Clement Little and His Library: The Origins of Edinburgh University Library (Edinburgh: Edinburgh University, 1980 ). 10Jean R. Guild and

Hydronic Heating Retrofits for Low-Rise Multifamily Buildings: Boiler Control Replacement and Monitoring

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

Dentz, J.; Henderson, H.; Varshney, K.

2013-10-01

The ARIES Collaborative, a U.S. Department of Energy Building America research team, partnered with NeighborWorks America affiliate Homeowners' Rehab Inc. of Cambridge, Massachusetts, to implement and study improvements to the central hydronic heating system in one of the nonprofit's housing developments. The heating control systems in the three-building, 42-unit Columbia Cambridge Alliance for Spanish Tenants housing development were upgraded.

The British Experience in Iraq, 2007: A Perspective on the Utility of Force

DTIC Science & Technology

2012-05-17

exploit JAM’s temporary disarray to muscle in on the electricity franchise . This provoked a violent backlash from JAM whose fighters besieged Wahili’s...approximation to absolute war, although its instrumental value is difficult to divine given its self-defeating absurdity.) 13 Beatrice Heuser, The Evolution ...Heuser, The Evolution of Strategy, (Cambridge: Cambridge University Press, 2010), Page 489. “The Clausewitzian model according to which governments

Parallel Algorithms for Computer Vision.

DTIC Science & Technology

1989-01-01

34 IEEE Tran. Pattern Ankyaij and Ma- Artifcial Intelligence , Tokyo, 1979. chine Intelligence , 6, 1984. Kirkpatrick, S., C.D. Gelatt, Jr. and M.P. Vecchi...MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB T P06010 JAN 89 ETL-0529 UNCLASSIFIED DACA76-85-C-0010 F.’G 12/1I N mommiimmmiiso...PoggioI Massachusetts Institute of Technology i Artificial Intelligence Laboratory 545 Technology Square Cambridge, Massachusetts 02139 DTIC January

Understanding Tumor Dormancy as a Means of Secondary Prevention

DTIC Science & Technology

2017-10-01

Hannon CONTRACTING ORGANIZATION: University of Cambridge, UK Cambridge, CB 0RE REPORT DATE: October 2017 TYPE OF REPORT : Annual PREPARED FOR...Distribution Unlimited The views, opinions and/or findings contained in this report are those of the author(s) and should not be construed as an official...Department of the Army position, policy or decision unless so designated by other documentation. REPORT DOCUMENTATION PAGE Form Approved OMB No

Natural Object Categorization.

DTIC Science & Technology

1987-11-01

6-A194 103 NATURAL OBJECT CATEGORIZATION(U) MASSACHUSETTS INST OF 1/3 TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB R F DBICK NOY 87 AI-TR-1091 NBSSI4...ORGANI1ZATION NAME AN40 ACORES$ 10. PROGRAM ELEMENT. PROJECT. TASK Artificial Inteligence Laboratory AREA A WORK UNIT MUMBERS 545 Technology Square Cambridge...describes research done at the Department of Brain and Cognitive Sciences and the Artificial Intelligence Laboratory at the Massachusetts Institute of

Analysis of pharmacist-patient communication using the Calgary-Cambridge guide.

PubMed

Greenhill, Nicola; Anderson, Claire; Avery, Anthony; Pilnick, Alison

2011-06-01

This study explored communication between pharmacists and patients through application of the Calgary-Cambridge guide [1] to appointment-based pharmacist-patient consultations and considers use of the guide in pharmacy education. Eighteen patients attending appointment-based consultations with five pharmacists were recruited to this qualitative study. Consultations were audio-recorded and observed. Transcripts were coded according to the use of skills within the guide and analysed thematically. The results showed good use of many skills by pharmacists, particularly signposting and closing the session. Some skills were poorly represented such as listening effectively, eliciting the patient's perspective, effective use of computers and creating patient-centred consultations. A key theme of social conversation was present in the data but this skill was not defined in the guide. The Calgary-Cambridge guide was developed for use in medical consultations but its application to pharmacist-patient consultations showed that the guide could be successfully used in pharmacy with some minor alterations. Pharmacists may need more training to improve the use of specific communication skills including how to conduct a patient-centred consultation. The Calgary-Cambridge guide is well aligned with many aspects of pharmacist-patient consultations and could help pharmacists to improve their consultation skills. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Nutrition in medical education: reflections from an initiative at the University of Cambridge

PubMed Central

Ball, Lauren; Crowley, Jennifer; Laur, Celia; Rajput-Ray, Minha; Gillam, Stephen; Ray, Sumantra

2014-01-01

Landmark reports have confirmed that it is within the core responsibilities of doctors to address nutrition in patient care. There are ongoing concerns that doctors receive insufficient nutrition education during medical training. This paper provides an overview of a medical nutrition education initiative at the University of Cambridge, School of Clinical Medicine, including 1) the approach to medical nutrition education, 2) evaluation of the medical nutrition education initiative, and 3) areas identified for future improvement. The initiative utilizes a vertical, spiral approach during the clinically focused years of the Cambridge undergraduate and graduate medical degrees. It is facilitated by the Nutrition Education Review Group, a group associated with the UK Need for Nutrition Education/Innovation Programme, and informed by the experiences of their previous nutrition education interventions. Three factors were identified as contributing to the success of the nutrition education initiative including the leadership and advocacy skills of the nutrition academic team, the variety of teaching modes, and the multidisciplinary approach to teaching. Opportunities for continuing improvement to the medical nutrition education initiative included a review of evaluation tools, inclusion of nutrition in assessment items, and further alignment of the Cambridge curriculum with the recommended UK medical nutrition education curriculum. This paper is intended to inform other institutions in ongoing efforts in medical nutrition education. PMID:24899813

Instability, investment, disasters, and demography: natural disasters and fertility in Italy (1820-1962) and Japan (1671-1965).

PubMed

Lin, C-Y Cynthia

2010-03-01

This article examines whether natural disasters affect fertility-a topic little explored but of policy importance given relevance to policies regarding disaster insurance, foreign aid, and the environment. The identification strategy uses historic regional data to exploit natural variation within each of two countries: one European country-Italy (1820-1962), and one Asian country-Japan (1671-1965). The choice of study settings allows consideration of Jones' (The European miracle, Cambridge University Press, Cambridge, 1981) theory that preindustrial differences in income and population between Asia and Europe resulted from the fertility response to different environmental risk profiles. According to the results, short-run instability, particularly that arising from the natural environment, appears to be associated with a decrease in fertility-thereby suggesting that environmental shocks and economic volatility are associated with a decrease in investment in the population size of future generations. The results also show that, contrary to Jones' (The European miracle, Cambridge University Press, Cambridge, 1981) theory, differences in fertility between Italy and Japan cannot be explained away by disaster proneness alone. Research on the effects of natural disasters may enable social scientists and environmentalists alike to better predict the potential effects of the increase in natural disasters that may result from global climate change.

Hybrid Taxis Give Fuel Economy a Lift, Clean Cities, Fleet Experiences, April 2009 (Fact Sheet)

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

Not Available

2009-04-01

Clean Cities helped Boston, San Antonio, and Cambridge create hybrid taxi programs. The hybrid taxis are able to achieve about twice the gas mileage of a conventional taxi while helping cut gasoline use and fuel costs. Tax credits and other incentives are helping both company owners and drivers make the switch to hybrids. Program leaders have learned some important lessons other cities can benefit from including learning a city's taxi structure, relaying benefits to drivers, and understanding the needs of owners.

[Efficiency of etiologic correction of concomitant ascaridosis in the complex treatment of chronic pancreatitis].

PubMed

Babinets', L S; Droniak, Iu V; Pliashko, K O; Babinets', A I

2014-11-01

The of antihelmintic preparation albendazole using in the complex treatment of patients with chronic pancreatitis with the concomitant ascaridosis was promote regression of clinical demonstration of basic and concomitant diseases (P < 0.05). Options of coprogram and the structural state of pancreas from data of ultrasonography in marks by Marseille-Cambridge classification of chronic pancreatitis, after the conducted treatment became the better (P < 0.05), that established expedience of the use of albendazole in complex treatment of patients with a chronic pancreatitis with a concomitant ascaridosis.

GlycomeDB – integration of open-access carbohydrate structure databases

PubMed Central

Ranzinger, René; Herget, Stephan; Wetter, Thomas; von der Lieth, Claus-Wilhelm

2008-01-01

Background Although carbohydrates are the third major class of biological macromolecules, after proteins and DNA, there is neither a comprehensive database for carbohydrate structures nor an established universal structure encoding scheme for computational purposes. Funding for further development of the Complex Carbohydrate Structure Database (CCSD or CarbBank) ceased in 1997, and since then several initiatives have developed independent databases with partially overlapping foci. For each database, different encoding schemes for residues and sequence topology were designed. Therefore, it is virtually impossible to obtain an overview of all deposited structures or to compare the contents of the various databases. Results We have implemented procedures which download the structures contained in the seven major databases, e.g. GLYCOSCIENCES.de, the Consortium for Functional Glycomics (CFG), the Kyoto Encyclopedia of Genes and Genomes (KEGG) and the Bacterial Carbohydrate Structure Database (BCSDB). We have created a new database called GlycomeDB, containing all structures, their taxonomic annotations and references (IDs) for the original databases. More than 100000 datasets were imported, resulting in more than 33000 unique sequences now encoded in GlycomeDB using the universal format GlycoCT. Inconsistencies were found in all public databases, which were discussed and corrected in multiple feedback rounds with the responsible curators. Conclusion GlycomeDB is a new, publicly available database for carbohydrate sequences with a unified, all-encompassing structure encoding format and NCBI taxonomic referencing. The database is updated weekly and can be downloaded free of charge. The JAVA application GlycoUpdateDB is also available for establishing and updating a local installation of GlycomeDB. With the advent of GlycomeDB, the distributed islands of knowledge in glycomics are now bridged to form a single resource. PMID:18803830

ProBiS-database: precalculated binding site similarities and local pairwise alignments of PDB structures.

PubMed

Konc, Janez; Cesnik, Tomo; Konc, Joanna Trykowska; Penca, Matej; Janežič, Dušanka

2012-02-27

ProBiS-Database is a searchable repository of precalculated local structural alignments in proteins detected by the ProBiS algorithm in the Protein Data Bank. Identification of functionally important binding regions of the protein is facilitated by structural similarity scores mapped to the query protein structure. PDB structures that have been aligned with a query protein may be rapidly retrieved from the ProBiS-Database, which is thus able to generate hypotheses concerning the roles of uncharacterized proteins. Presented with uncharacterized protein structure, ProBiS-Database can discern relationships between such a query protein and other better known proteins in the PDB. Fast access and a user-friendly graphical interface promote easy exploration of this database of over 420 million local structural alignments. The ProBiS-Database is updated weekly and is freely available online at http://probis.cmm.ki.si/database.

Construction of crystal structure prototype database: methods and applications.

PubMed

Su, Chuanxun; Lv, Jian; Li, Quan; Wang, Hui; Zhang, Lijun; Wang, Yanchao; Ma, Yanming

2017-04-26

Crystal structure prototype data have become a useful source of information for materials discovery in the fields of crystallography, chemistry, physics, and materials science. This work reports the development of a robust and efficient method for assessing the similarity of structures on the basis of their interatomic distances. Using this method, we proposed a simple and unambiguous definition of crystal structure prototype based on hierarchical clustering theory, and constructed the crystal structure prototype database (CSPD) by filtering the known crystallographic structures in a database. With similar method, a program structure prototype analysis package (SPAP) was developed to remove similar structures in CALYPSO prediction results and extract predicted low energy structures for a separate theoretical structure database. A series of statistics describing the distribution of crystal structure prototypes in the CSPD was compiled to provide an important insight for structure prediction and high-throughput calculations. Illustrative examples of the application of the proposed database are given, including the generation of initial structures for structure prediction and determination of the prototype structure in databases. These examples demonstrate the CSPD to be a generally applicable and useful tool for materials discovery.

Construction of crystal structure prototype database: methods and applications

NASA Astrophysics Data System (ADS)

Su, Chuanxun; Lv, Jian; Li, Quan; Wang, Hui; Zhang, Lijun; Wang, Yanchao; Ma, Yanming

2017-04-01

Crystal structure prototype data have become a useful source of information for materials discovery in the fields of crystallography, chemistry, physics, and materials science. This work reports the development of a robust and efficient method for assessing the similarity of structures on the basis of their interatomic distances. Using this method, we proposed a simple and unambiguous definition of crystal structure prototype based on hierarchical clustering theory, and constructed the crystal structure prototype database (CSPD) by filtering the known crystallographic structures in a database. With similar method, a program structure prototype analysis package (SPAP) was developed to remove similar structures in CALYPSO prediction results and extract predicted low energy structures for a separate theoretical structure database. A series of statistics describing the distribution of crystal structure prototypes in the CSPD was compiled to provide an important insight for structure prediction and high-throughput calculations. Illustrative examples of the application of the proposed database are given, including the generation of initial structures for structure prediction and determination of the prototype structure in databases. These examples demonstrate the CSPD to be a generally applicable and useful tool for materials discovery.

A Semantics of Synchronization.

DTIC Science & Technology

1980-09-01

suggestion of having very hungry philosophers. One can easily imagine the complexity of the equivalent implementation using semaphores . Synchronization types...Edinburgh, July 1978. [STAR79] Stark, E.W., " Semaphore Primitives and Fair Mutual Exclusion," TM-158, Laboratory for Computer Science, M.I.T., Cambridge...AD-AQ91 015 MASSACHUSETTS INST OF TECH CAMBRIDGE LAB FOR COMPUTE--ETC F/S 9/2 A SEMANTICS OF SYNCHRONIZATION .(U) .C SEP 80 C A SEAQUIST N00015-75

New Insights on Visual Cortex. Abstracts. Center for Visual Science Symposium (16th) Held in Rochester, New York on June 16-18, 1988

DTIC Science & Technology

1988-06-01

Cortex of the Cat John G. Robson Craik Physiological Laboratory Cambridge University Cambridge, England When tested with spatially-localized stimuli...University, New York, NY Stanley Klein - School of Optometry, University Berkeley, Berkeley, CA Jennifer Knight - Neurobiology & Behavior, Cornell University...Village, Poughkeepsie, NY Jeffrcy Lubin - Psychology Department, University of PA, Philadelphia, PA Jennifer S. Lund - University of Pittsburgh

Autobiography of Sir George Biddell Airy

NASA Astrophysics Data System (ADS)

Airy, George Biddell; Airy, Wilfred

2010-06-01

Preface; 1. Personal sketch of George Biddell Airy; 2. From his birth to his taking his B.A. degree; 3. At Trinity College, Cambridge; 4. At Cambridge Observatory; 5. At Greenwich Observatory, 1836-1846; 6. At Greenwich Observatory, 1846-1856; 7. At Greenwich Observatory, 1856-1866; 8. At Greenwich Observatory, 1866-1876; 9. At Greenwich Observatory to his resignation in 1881; 10. At the White House, Greewich, to his death; Appendix: List of printed papers; Index.

A Set of Orthogonal Polynomials That Generalize the Racah Coefficients or 6 - j Symbols.

DTIC Science & Technology

1978-03-01

Generalized Hypergeometric Functions, Cambridge Univ. Press, Cambridge, 1966. [11] D. Stanton, Some basic hypergeometric polynomials arising from... Some bas ic hypergeometr ic an a logues of the classical orthogonal polynomials and applications , to appear. [3] C. de Boor and G. H. Golub , The...Report #1833 A SET OF ORTHOGONAL POLYNOMIALS THAT GENERALIZE THE RACAR COEFFICIENTS OR 6 — j SYMBOLS Richard Askey and James Wilson •

DDN (Defence Data Network) Protocol Implementations and Vendors Guide

DTIC Science & Technology

1988-08-01

Artificial Intelligence Laboratory Room NE43-723 545 Technology Square Cambridge, MA 02139 (617) 253-8843 S John Wroclawski, (JTW@AI.AJ.MIT.EDU...Massachusetts Institute of Technology Artificial Intelligence Laboratory Room NE43-743 545 Technology Square 0 Cambridge, MA 02139 (617) 253-7885 ORDERING...TCP/IP Network Software for PC-DOS Systems CPU: IBM-PC/XT/AT/compatible in conjunction with EXOS 205 Inteligent Ethernet Controller for PCbus 0/s

Exploiting Lexical Regularities in Designing Natural Language Systems.

DTIC Science & Technology

1988-04-01

ELEMENT. PROJECT. TASKN Artificial Inteligence Laboratory A1A4WR NTumet 0) 545 Technology Square Cambridge, MA 02139 Ln *t- CONTROLLING OFFICE NAME AND...RO-RI95 922 EXPLOITING LEXICAL REGULARITIES IN DESIGNING NATURAL 1/1 LANGUAGE SYSTENS(U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE...oes.ary and ftdou.Ip hr Nl wow" L,2This paper presents the lexical component of the START Question Answering system developed at the MIT Artificial

Human Factors in Aircraft Maintenance

DTIC Science & Technology

2001-03-01

795 - 3-798. Reason, J . (1990). Human Error. Cambridge: Cambridge University Press. Schmidt, J ., Schmorrow, D . and Figlock, R. (2000). Human factors...and so on. When each step is described in sufficient detail, the task description is complete and task analysis can begin (e.g. Drury, Paramore , Van... Paramore , B., Van Cott, H.P., Grey, S.M. and Corlett, E.M.(1987). Task analysis. In G. Salvendy (Ed) Handbook of Human Factors, Chapter 3.4. New

The Characterization and Circumvention of Carbon Nanotube Junctions - The Route to Practical Carbon Conductors Through Extreme Frequency, Fields, and Light

DTIC Science & Technology

2015-05-22

Conductors Through Extreme Frequency, Fields, and Light Krzysztof Koziol THE CHANCELLOR, MASTER AND SCHOLARS OF THE UNIVERISTY OF CAMBRIDGE...2011 to 31 August 2014 Air Force Research Laboratory Air Force Office of Scientific Research European Office of Aerospace Research and...Carbon Conductors Through Extreme Frequency, Fields, and Light Krzysztof Koziol THE CHANCELLOR, MASTER AND SCHOLARS OF THE UNIVERISTY OF CAMBRIDGE THE

Selection and Effects of Channels in Distributed Communication and Decision Making Tasks: A Theoretical Review and a Proposed Research Paradigm

DTIC Science & Technology

1988-02-01

1982). Integration and involvement in speaking, writing, and oral literture. In Deborah Tannen (Ed.) Spoken and written lanquage: Exploring orality and...University. Gump rz, John J. (1982). Discourse strategies. Cambridge: Cambridge University Press. Gumperz, John J., & Tannen , Deborah . (1978...and the transition to literacy. In Deborah Tannen (Ed.) Coherence in spoken and written discourse. Gutek, Barbara A., Bikson, Tora K., & Mankin, Don

Conflict for Resources: Water in the Lake Chad Basin

DTIC Science & Technology

2009-01-01

Security 19 (1994), http://www.library.utoronto.ca/pcs/evidence (accessed 10 February 2009). 11 Miriam Lowi, Water and Power (Cambridge, UK : Cambridge...states wage wars and how scarce natural resources influence the states. Carl von Clausewitz’s treatise, On War serves as a starting point for any...has lots of water, very little of it is freshwater. Miriam Lowi, author of Water and Power describes political dynamics of high and low politics. High

The production of oxygen and metal from lunar regolith

NASA Astrophysics Data System (ADS)

Schwandt, Carsten; Hamilton, James A.; Fray, Derek J.; Crawford, Ian A.

2012-12-01

The present article summarises the various methods that have been, and still are, explored for the production of oxygen from lunar materials. These include the classical concepts based on chemical reduction with hydrogen or methane, vapour phase pyrolysis, sulphuric acid treatment, and molten oxide electrolysis. Our main focus in this paper is on a novel approach developed at the University of Cambridge that employs molten salt electrochemistry to achieve the combined winning of oxygen and metal from solid lunar materials of varying composition. This makes the Cambridge process attractive because it will work equally well in mare as in highland regions. We also discuss the implications of the recent apparent discovery of water ice at the poles of the Moon and conclude that, even if this discovery is confirmed, it will nevertheless be desirable to provide oxygen at non-polar localities, and the Cambridge process is a strong candidate for achieving this.

Analysis of the viewing zone of the Cambridge autostereoscopic display.

PubMed

Dodgson, N A

1996-04-01

The Cambridge autostereoscopic three-dimensional display is a time-multiplexed device that gives both stereo and movement parallax to the viewer without the need for any special glasses. This analysis derives the size and position of the fully illuminated, and hence useful, viewing zone for a Cambridge display. The viewing zone of such a display is shown to be completely determined by four parameters: the width of the screen, the optimal distance of the viewer from the screen, the width over which an image can be seen across the whole screen at this optimal distance, and the number of views. A display's viewing zone can thus be completely described without reference to the internal implementation of the device. An equation that describes what the eye sees from any position in front of the display is derived. The equations derived can be used in both the analysis and design of this type of time-multiplexed autostereoscopic display.

Economic dynamics with financial fragility and mean-field interaction: A model

NASA Astrophysics Data System (ADS)

Di Guilmi, C.; Gallegati, M.; Landini, S.

2008-06-01

Following Aoki’s statistical mechanics methodology [Masanao Aoki, New Approaches to Macroeconomic Modeling, Cambridge University Press, 1996; Masanao Aoki, Modeling Aggregate Behaviour and Fluctuations in Economics, Cambridge University Press, 2002; Masanao Aoki, and Hiroshi Yoshikawa, Reconstructing Macroeconomics, Cambridge University Press, 2006], we provide some insights into the well-known works of [Bruce Greenwald, Joseph Stiglitz, Macroeconomic models with equity and credit rationing, in: R. Hubbard (Ed.), Information, Capital Markets and Investment, Chicago University Press, Chicago, 1990; Bruce Greenwald, Joseph Stiglitz, Financial markets imperfections and business cycles, Quarterly journal of Economics (1993)]. Specifically, we reach analytically a closed form solution of their models overcoming the aggregation problem. The key idea is to represent the economy as an evolving complex system, composed by heterogeneous interacting agents, that can be partitioned into a space of macroscopic states. This meso level of aggregation permits to adopt mean-field interaction modeling and master equation techniques.

Structural Ceramics Database

National Institute of Standards and Technology Data Gateway

SRD 30 NIST Structural Ceramics Database (Web, free access)   The NIST Structural Ceramics Database (WebSCD) provides evaluated materials property data for a wide range of advanced ceramics known variously as structural ceramics, engineering ceramics, and fine ceramics.

mTM-align: a server for fast protein structure database search and multiple protein structure alignment.

PubMed

Dong, Runze; Pan, Shuo; Peng, Zhenling; Zhang, Yang; Yang, Jianyi

2018-05-21

With the rapid increase of the number of protein structures in the Protein Data Bank, it becomes urgent to develop algorithms for efficient protein structure comparisons. In this article, we present the mTM-align server, which consists of two closely related modules: one for structure database search and the other for multiple structure alignment. The database search is speeded up based on a heuristic algorithm and a hierarchical organization of the structures in the database. The multiple structure alignment is performed using the recently developed algorithm mTM-align. Benchmark tests demonstrate that our algorithms outperform other peering methods for both modules, in terms of speed and accuracy. One of the unique features for the server is the interplay between database search and multiple structure alignment. The server provides service not only for performing fast database search, but also for making accurate multiple structure alignment with the structures found by the search. For the database search, it takes about 2-5 min for a structure of a medium size (∼300 residues). For the multiple structure alignment, it takes a few seconds for ∼10 structures of medium sizes. The server is freely available at: http://yanglab.nankai.edu.cn/mTM-align/.

Comprehensive analysis of the N-glycan biosynthetic pathway using bioinformatics to generate UniCorn: A theoretical N-glycan structure database.

PubMed

Akune, Yukie; Lin, Chi-Hung; Abrahams, Jodie L; Zhang, Jingyu; Packer, Nicolle H; Aoki-Kinoshita, Kiyoko F; Campbell, Matthew P

2016-08-05

Glycan structures attached to proteins are comprised of diverse monosaccharide sequences and linkages that are produced from precursor nucleotide-sugars by a series of glycosyltransferases. Databases of these structures are an essential resource for the interpretation of analytical data and the development of bioinformatics tools. However, with no template to predict what structures are possible the human glycan structure databases are incomplete and rely heavily on the curation of published, experimentally determined, glycan structure data. In this work, a library of 45 human glycosyltransferases was used to generate a theoretical database of N-glycan structures comprised of 15 or less monosaccharide residues. Enzyme specificities were sourced from major online databases including Kyoto Encyclopedia of Genes and Genomes (KEGG) Glycan, Consortium for Functional Glycomics (CFG), Carbohydrate-Active enZymes (CAZy), GlycoGene DataBase (GGDB) and BRENDA. Based on the known activities, more than 1.1 million theoretical structures and 4.7 million synthetic reactions were generated and stored in our database called UniCorn. Furthermore, we analyzed the differences between the predicted glycan structures in UniCorn and those contained in UniCarbKB (www.unicarbkb.org), a database which stores experimentally described glycan structures reported in the literature, and demonstrate that UniCorn can be used to aid in the assignment of ambiguous structures whilst also serving as a discovery database. Copyright © 2016 Elsevier Ltd. All rights reserved.

URS DataBase: universe of RNA structures and their motifs.

PubMed

Baulin, Eugene; Yacovlev, Victor; Khachko, Denis; Spirin, Sergei; Roytberg, Mikhail

2016-01-01

The Universe of RNA Structures DataBase (URSDB) stores information obtained from all RNA-containing PDB entries (2935 entries in October 2015). The content of the database is updated regularly. The database consists of 51 tables containing indexed data on various elements of the RNA structures. The database provides a web interface allowing user to select a subset of structures with desired features and to obtain various statistical data for a selected subset of structures or for all structures. In particular, one can easily obtain statistics on geometric parameters of base pairs, on structural motifs (stems, loops, etc.) or on different types of pseudoknots. The user can also view and get information on an individual structure or its selected parts, e.g. RNA-protein hydrogen bonds. URSDB employs a new original definition of loops in RNA structures. That definition fits both pseudoknot-free and pseudoknotted secondary structures and coincides with the classical definition in case of pseudoknot-free structures. To our knowledge, URSDB is the first database supporting searches based on topological classification of pseudoknots and on extended loop classification.Database URL: http://server3.lpm.org.ru/urs/. © The Author(s) 2016. Published by Oxford University Press.

URS DataBase: universe of RNA structures and their motifs

PubMed Central

Baulin, Eugene; Yacovlev, Victor; Khachko, Denis; Spirin, Sergei; Roytberg, Mikhail

2016-01-01

The Universe of RNA Structures DataBase (URSDB) stores information obtained from all RNA-containing PDB entries (2935 entries in October 2015). The content of the database is updated regularly. The database consists of 51 tables containing indexed data on various elements of the RNA structures. The database provides a web interface allowing user to select a subset of structures with desired features and to obtain various statistical data for a selected subset of structures or for all structures. In particular, one can easily obtain statistics on geometric parameters of base pairs, on structural motifs (stems, loops, etc.) or on different types of pseudoknots. The user can also view and get information on an individual structure or its selected parts, e.g. RNA–protein hydrogen bonds. URSDB employs a new original definition of loops in RNA structures. That definition fits both pseudoknot-free and pseudoknotted secondary structures and coincides with the classical definition in case of pseudoknot-free structures. To our knowledge, URSDB is the first database supporting searches based on topological classification of pseudoknots and on extended loop classification. Database URL: http://server3.lpm.org.ru/urs/ PMID:27242032

Band Gap Tuning in 2D Layered Materials by Angular Rotation.

PubMed

Polanco-Gonzalez, Javier; Carranco-Rodríguez, Jesús Alfredo; Enríquez-Carrejo, José L; Mani-Gonzalez, Pierre G; Domínguez-Esquivel, José Manuel; Ramos, Manuel

2017-02-08

We present a series of computer-assisted high-resolution transmission electron (HRTEM) simulations to determine Moiré patters by induced twisting effects between slabs at rotational angles of 3°, 5°, 8°, and 16°, for molybdenum disulfide, graphene, tungsten disulfide, and tungsten selenide layered materials. In order to investigate the electronic structure, a series of numerical simulations using density functional methods (DFT) methods was completed using Cambridge serial total energy package (CASTEP) with a generalized gradient approximation to determine both the band structure and density of states on honeycomb-like new superlattices. Our results indicated metallic transitions when the rotation approached 8° with respect to each other laminates for most of the two-dimensional systems that were analyzed.

Modelling large deformation and soil—water—structure interaction with material point method: Briefing on MPM2017 conference

NASA Astrophysics Data System (ADS)

Rohe, Alexander; Liang, Dongfang

2017-06-01

The 1st International Conference on the Material Point Method for "Modelling Large Deformation and Soil-Water-Structure Interaction" (MPM2017) was held in Delft, The Netherlands on 10-13 January 2017. This is the first conference organised by the Anura3D MPM Research Community, following a series of international workshops and symposia previously held in The Netherlands, UK, Spain and Italy, as part of the European Commission FP7 Marie-Curie project MPM-DREDGE. We are delighted to present seven contributions in this Special Column of the Journal of Hydrodynamics, and take this opportunity to announce that the 2nd conference, MPM2019, will be held in Cambridge, UK in January 2019.

Band Gap Tuning in 2D Layered Materials by Angular Rotation

PubMed Central

Polanco-Gonzalez, Javier; Carranco-Rodríguez, Jesús Alfredo; Enríquez-Carrejo, José L.; Mani-Gonzalez, Pierre G.; Domínguez-Esquivel, José Manuel; Ramos, Manuel

2017-01-01

We present a series of computer-assisted high-resolution transmission electron (HRTEM) simulations to determine Moiré patters by induced twisting effects between slabs at rotational angles of 3°, 5°, 8°, and 16°, for molybdenum disulfide, graphene, tungsten disulfide, and tungsten selenide layered materials. In order to investigate the electronic structure, a series of numerical simulations using density functional methods (DFT) methods was completed using Cambridge serial total energy package (CASTEP) with a generalized gradient approximation to determine both the band structure and density of states on honeycomb-like new superlattices. Our results indicated metallic transitions when the rotation approached 8° with respect to each other laminates for most of the two-dimensional systems that were analyzed. PMID:28772507

First AXAF Fellowships Awarded

NASA Astrophysics Data System (ADS)

1998-03-01

The AXAF (Advanced X-ray Astrophysics Facility) Science Center has announced the selection of five scientists to inaugurate the AXAF Postdoctoral Fellowship Program. Competition for the fellowships was open to all recent astronomy and astrophysics graduates worldwide. The AXAF Fellows will work for three years at a host astronomical institution in the United States where they will investigate topics broadly related to the scientific mission of AXAF. Additional AXAF Fellows will be selected each year over the course of the program. The AXAF Fellowship Program is a joint venture between NASA and the AXAF Science Center in cooperation with the host institutions. The AXAF Science Center is operated by the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts and funded by NASA through the Marshall Space Flight Center. "We are elated at the outstanding group of Fellows," said Harvey Tananbaum, the Director of the AXAF Science Center. "They will be working during the exciting period when the first X-ray images will be received from AXAF." Nancy Remage Evans, AXAF Fellowship Program Coordinator added, "The program will also encourage AXAF related work at institutions throughout the United States." An independent panel of scientists selected the honorees. The first AXAF Fellows and the host institutions at which they will hold their fellowships are: David Buote (University of California, Santa Cruz), Tiziana Di Matteo (Harvard-Smithsonian Center for Astrophysics), Ann Esin (California Institute of Technology), Joseph Mohr (University of Chicago), and Edward Moran (Massachusetts Institute of Technology). AXAF, the third of NASA's Great Observatories after the Hubble Space Telescope and the Compton Gamma Ray Observatory, is the largest and most sophisticated X-ray telescope ever built. When it is launched in December of this year, AXAF's high resolution will provide new information about exploding stars, black holes, colliding galaxies, and other extremely hot regions of the universe. Further information about the AXAF satellite is available at the World Wide Web at http://xrtpub.harvard.edu/. Further information about the Fellowship program is available at http://asc.harvard.edu/fellows/. Supplemental Information on 1998 AXAF Fellows: * David Buote graduated from MIT, Cambridge MA 02139 * Tiziana DiMatteo graduated from Cambridge University, Cambridge CB30HA UK * Ann Esin graduated from Harvard University, Cambridge, MA 02138 * Joseph Mohr graduated from Harvard University, Cambridge, MA 02138 * Edward Moran graduated from Columbia University, New York City, NY 10027

Oxford and Cambridge Boat Race: Performance, Pacing and Tactics Between 1890 and 2014.

PubMed

Edwards, Andrew M; Guy, Joshua H; Hettinga, Florentina J

2016-10-01

Currently no studies have examined the historical performances of Oxford and Cambridge Boat Race crews in the context of performance, pacing and tactics which is surprising as the event has routinely taken place annually for over 150 years on the same course. The purpose of this study was twofold, to firstly examine the historical development of performances and physical characteristics of crews over 124 years of the Oxford and Cambridge Boat Race between 1890 and 2014 and secondly to investigate the pacing and tactics employed by crews over that period. Linear regression modelling was applied to investigate the development of performance and body size for crews of eight male individuals over time from Boat Race archive data. Performance change over time was further assessed in 10-year clusters while four intra-race checkpoints were used to examine pacing and tactics. Significant correlations were observed between performance and time (1890-2014) for both Oxford (r = -0.67; p < 0.01) and Cambridge (r = -0.64; p < 0.01). There was no difference in mean performance times for Oxford (1170 ± 88 s) and Cambridge (1168 ± 89.8 s) during 1890-2014. Crew performance times improved over time with significant gains from baseline achieved in the 1950s (Cambridge) and the 1960s (Oxford), which coincided with significant change in the physicality of the competing crews (p < 0.01). There was no tactical advantage from commencing on either the Surrey or Middlesex station beyond chance alone; however, all crews (n = 228) adopted a fast-start strategy, with 81 % of victories achieved by the crew leading the race at the first intra-race checkpoint (24 % of total distance). Crews leading the race at the final checkpoint (83 % of total distance; 1143 m) achieved victory on 94 % of occasions. Performances and physical characteristics of the crews have changed markedly since 1890, with faster heavier crews now common. Tactically, gaining the early lead position with a fast-start strategy seems particularly meaningful to success in the Boat Race throughout the years, and has been of greater importance to race outcome than factors such as the starting station.

Investigation of prolific sheep from UK and Ireland for evidence on origin of the mutations in BMP15 (FecX(G), FecX(B)) and GDF9 (FecG(H)) in Belclare and Cambridge sheep.

PubMed

Mullen, Michael P; Hanrahan, James P; Howard, Dawn J; Powell, Richard

2013-01-01

This paper concerns the likely origin of three mutations with large effects on ovulation rate identified in the Belclare and Cambridge sheep breeds; two in the BMP15 gene (FecX(G) and FecX(B)) and the third (FecG(H)) in GDF9. All three mutations segregate in Belclare sheep while one, FecX(B), has not been found in the Cambridge. Both Belclare and Cambridge breeds are relatively recently developed composites that have common ancestry through the use of genetic material from the Finnish Landrace and Lleyn breeds. The development of both composites also involved major contributions from exceptionally prolific ewes screened from flocks in Ireland (Belclare) and Britain (Cambridge) during the 1960s. The objective of the current study was to establish the likely origin of the mutations (FecX(G), FecX(B) and FecG(H)) through analysis of DNA from Finnish Landrace and Lleyn sheep, and Galway and Texel breeds which contributed to the development of the Belclare breed. Ewes with exceptionally high prolificacy (hyper-prolific ewes) in current flocks on Irish farms were identified to simulate the screening of ewes from Irish flocks in the 1960s. DNA was obtained from: prolific ewes in extant flocks of Lleyn sheep (n = 44) on the Lleyn peninsula in Wales; hyper-prolific ewes (n = 41); prolific Galway (n = 41) ewes; Finnish Landrace (n = 124) and Texel (n = 19) ewes. The FecX(G) mutation was identified in Lleyn but not in Finnish Landrace, Galway or Texel sheep; FecX(B) was only found among the hyper-prolific ewes. The FecG(H) mutation was identified in the sample of Lleyn sheep. It was concluded from these findings that the Lleyn breed was the most likely source of the FecX(G) and FecG(H) mutations in Belclare and Cambridge sheep and that the FecX(B) mutation came from the High Fertility line that was developed using prolific ewes selected from commercial flocks in Ireland in the 1960's and subsequently used in the genesis of the Belclare.

A case study for a digital seabed database: Bohai Sea engineering geology database

NASA Astrophysics Data System (ADS)

Tianyun, Su; Shikui, Zhai; Baohua, Liu; Ruicai, Liang; Yanpeng, Zheng; Yong, Wang

2006-07-01

This paper discusses the designing plan of ORACLE-based Bohai Sea engineering geology database structure from requisition analysis, conceptual structure analysis, logical structure analysis, physical structure analysis and security designing. In the study, we used the object-oriented Unified Modeling Language (UML) to model the conceptual structure of the database and used the powerful function of data management which the object-oriented and relational database ORACLE provides to organize and manage the storage space and improve its security performance. By this means, the database can provide rapid and highly effective performance in data storage, maintenance and query to satisfy the application requisition of the Bohai Sea Oilfield Paradigm Area Information System.

Inorganic Crystal Structure Database (ICSD)

National Institute of Standards and Technology Data Gateway

SRD 84 FIZ/NIST Inorganic Crystal Structure Database (ICSD) (PC database for purchase)   The Inorganic Crystal Structure Database (ICSD) is produced cooperatively by the Fachinformationszentrum Karlsruhe(FIZ) and the National Institute of Standards and Technology (NIST). The ICSD is a comprehensive collection of crystal structure data of inorganic compounds containing more than 140,000 entries and covering the literature from 1915 to the present.

Phenoxide and alkoxide complexes of Mg, Al and Zn, and their use for the ring-opening polymerization of ℇ-caprolactone with initiators of different natures.

PubMed

Minyaev, Mikhail E; Nifant'ev, Ilya E; Shlyakhtin, Andrey V; Ivchenko, Pavel V; Lyssenko, Konstantin A

2018-05-01

A new packing polymorph of bis(2,6-di-tert-butyl-4-methylphenolato-κO)bis(tetrahydrofuran-κO)magnesium, [Mg(C 15 H 23 O) 2 (C 4 H 8 O) 2 ] or Mg(BHT) 2 (THF) 2 , (BHT is the 2,6-di-tert-butyl-4-methylphenoxide anion and THF is tetrahydrofuran), (1), has the same space group (P2 1 ) as the previously reported modification [Nifant'ev et al. (2017d). Dalton Trans. 46, 12132-12146], but contains three crystallographically independent molecules instead of one. The structure of (1) exhibits rotational disorder of the tert-butyl groups and positional disorder of a THF ligand. The complex of bis(2,6-di-tert-butyl-4-methylphenolato-κO)bis(μ 2 -ethyl glycolato-κ 2 O,O':κO)dimethyldialuminium, [Al 2 (CH 3 ) 2 (C 4 H 7 O 3 ) 2 (C 15 H 23 O) 2 ] or [(BHT)AlMe(OCH 2 COOEt)] 2 , (2), is a dimer located on an inversion centre and has an Al 2 O 2 rhomboid core. The 2-ethoxy-2-oxoethanolate ligand (OCH 2 COOEt) displays a μ 2 -κ 2 O,O':κO semi-bridging coordination mode, forming a five-membered heteronuclear Al-O-C-C-O ring. The same ligand exhibits positional disorder of the terminal methyl group. The redetermined structure of the heptanuclear complex octakis(μ 3 -benzyloxo-κO:κO:κO)hexaethylheptazinc, [Zn 7 (C 2 H 5 ) 6 (C 7 H 7 O) 8 ] or [Zn 7 (OCH 2 Ph) 8 Et 6 ], (3), possesses a bicubic Zn 7 O 8 core located at an inversion centre and demonstrates positional disorder of one crystallographically independent phenyl group. Cambridge Structural Database surveys are given for complexes structurally analogous to (2) and (3). Complexes (2) and (3), as well as derivatives of (1), are of interest as catalysts for the ring-opening polymerization of ℇ-caprolactone, and polymerization results are reported.

Assessing the Impact of Strategic Culture on Chinese Regional Security Policies in South Asia

DTIC Science & Technology

2011-05-19

36John Milton Cooper, Breaking the Heart of the World: Woodrow Wilson and the Fight for the League of Nations (Cambridge: Cambridge University Press...investment vehicles. 44Thomas L. Friedman , The Lexus and the Olive Tree (New York: Farrar, Straus, Giroux, 1999), 155. 16 regarding the control...Washington Post, June 13, 1999, A27. Cooper, John Milton . Breaking the Heart of the World: Woodrow Wilson and the Fight for the League of Nations

Inspection Methods in Programming: Cliches and Plans.

DTIC Science & Technology

1987-12-01

PROGRAM ELEMENT. PROJECT. TASK Artificial Inteligence Laboratory AREA & WORK UN IT NUMBERS J 545 Technology Square Cambridge, MA 02139 $L. CONTROLLING...U) MASSACHUSETTS INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB C RICH DEC 87 AI-M-±05 UNCLASSIFIED NW014-B5-K-0124 F/G 12/5 NL ’lllll l l l...S %P W. J % % %s MASSACHUSETTS INSTITUTE OF TECHNOLOGY N ARTIFICIAL INTELLIGENCE LABORATORY 00 A.I. Memo No. 1005 December 1987 N Inspection Methods

Real-Time Modeling of Cross-Body Flow for Torpedo Tube Recovery of the Phoenix Autonomous Underwater Vehicle (AUV)

DTIC Science & Technology

1998-03-01

34Numerical Recipes in C," second edition, Cambridge University Press, Cambridge England, 1992. Marco, David , "Autonomous Control of Underwater...in the viewer. -202- LIST OF REFERENCES Ames, Andrea L., Nadeau, David R., Moreland, John L., VRML 2.0 Sourcebook, Second edition, John Wiley...McGhee, Bob, "The Phoenix Autonomous Underwater Vehicle," AI-Based Mobile Robots, editors David Kortenkamp, Pete Bonasso and Robin Murphy, MJT/AAAI

Aircraft Wake Vortices: An Assessment of the Current Situation

DTIC Science & Technology

1991-01-01

1979 , DOT/TSC, Cambridge, MA. 36. Burnham, D.C., "Chicago Monostatic Acoustic Vortex Sensing System, Vol. I : Data Collection and Reduction," FAA-RD-79...April 1979 , DOT/TSC, Cambridge, MA. 45. Hallock, J.N., "Vortex Advisory System Safety Analysis; Vol. I : Analytical Model," FAA-RD-78-68. I , September...Industry Representatives," March 1979 , Economics & Science Planning Inc., Washington, DC. 106. Hallock, J.N., "Vortex Advisory System, Vol. I : Effectiveness

Governing Geoengineering Research: A Political and Technical Vulnerability Analysis of Potential Near-Term Options

DTIC Science & Technology

2011-01-01

weather events, or the spread of tropical diseases into North America. The net A Vulnerability-and-Response-Option Analysis Framework for a Risk...Avoidable Surprises, Cambridge: Cambridge University Press, 2002. Doney, Scott C., Victoria J. Fabry , Richard A. Feely, and Joan A. Kleypas, “Ocean...Falkenmark, Louise Karlberg, Robert W. Corell, Victoria J. Fabry , James Hansen, Brian Walker, Diana Liverman, Katherine Richardson, Paul Crutzen, and

Special Relationship What are the Strategic Choices available to the UK after the US Pivot to Asia

DTIC Science & Technology

2013-02-14

Emergency’ see Jones, Matthew, Conflict and Confrontation in South East Asia , 1961 – 1965, (Cambridge: CUP, 2002). 7 A spokesman at the Bureau of Asian...Stanford: Stanford University Press, 2010. Jones, Matthew. Conflict and Confrontation in South East Asia , 1961 – 1965. Cambridge: CUP, 2002...greater role in influencing events in the Asia -Pacific region. This strategic decision is complicated by the fact that the United States is trying to

The Alliance Decides the Mission? Multilateral Decision Making at the UN and NATO on Libya, 2010-2011

DTIC Science & Technology

2012-06-01

Bruce D. Jones, Shepard Forman, and Richard Gowan, 20-44, (Cambridge: Cambridge University Press, 2010). 65 Steve Weber, “Shaping the Postwar Balance...because the United States provided strong counterbalancing leadership, it also enabled increased French- German cooperation, wherein French concerns of... German military power were somewhat mitigated by the U.S. promise of continued involvement.93 An investigation of a few key articles in the North

Selection and Effects of Channels in Distributed Communication and Decision-Making Tasks: A Theoretical Review and a Proposed Research Paradigm

DTIC Science & Technology

1988-04-01

in speaking, writing, and oral literture. In Deborah Tannen (Ed.) Spoken and written lanquage: Exploring orality and literacy. Norwood, NJ: Ablex...strategies. Cambridge: Cambridge .’. University Press. Gumperz, John J., Tannen , Deborah . (1978). Individual and social differences in lanquaqe use. In W. Wang...Hannah, & O’Connor, Mary Catherine. (1984). Cohesion in spoken and written discourse: Ethnic style and the transition to literacy. In Deborah Tannen (Ed

Instantly Basing Locust Swarms: New Options for Future Air Operations

DTIC Science & Technology

2012-06-01

force’s fighting potential.”51 Moreover, JP 3-0 specifically emphasizes “Securing and protecting forces, bases, JSAs [Joint Storage Areas], and LOCs ...Smith and Leo Marx (Cambridge, MA: The MIT Press, 1994), 101-113. 64 Hughes, “Technological Momentum,”108. 65 John Law, "Technology and Heterogeneous...Technology Drive History?, edited by Merritt Roe Smith and Leo Marx, 101-113. Cambridge, MA: The MIT Press, 1994. Jean, Grace V. "Remotely Piloted

Fighting Dark Networks: Using Social Network Analysis to Implement the Special Operations Targeting Process for Direct and Indirect Approaches

DTIC Science & Technology

2013-03-01

Wouter De Nooy, Andrej Mrvar and Vladimir Batagelj , Exploratory Social Network Analysis with Pajek, (New York: Cambridge University Press, 2005), 5...Granovetter, “The Strength of Weak Ties,” 1350–1368. 151 de Nooy, Mrvar , and Batagelj , Exploratory Social Network Analysis with Pajek, 151. 152...Spacetime Wrinkles Exhibit (1995). de Nooy, Wouter, Andrej Mrvar , and Vladimir Batagelj . Exploratory Social Network Analysis with Pajek. Cambridge

A Grey Area: Congressional Oversight of the Middle Ground Between Title 10 and Title 50

DTIC Science & Technology

2012-06-01

for 1981, Title V. 43 Eric Rosenbach and Aki J. Peritz, Trials by Fire , Counterterrorism and the Law (Cambridge: Belfer Center for Science and...Potomac Books, 2005), 59. The authors use different terms to describe the same phenomena, Johnson uses police patrolling and fire fighting instead. 56...Trials by Fire , Counterterrorism and the Law (Cambridge: Belfer Center for Science and International Affairs, 2010), 8. 44 Kibbe, “The Rise of the

Stability of libration points in the restricted four-body problem with variable mass

NASA Astrophysics Data System (ADS)

Mittal, Amit; Aggarwal, Rajiv; Suraj, Md. Sanam; Bisht, Virender Singh

2016-10-01

We have investigated the stability of the Lagrangian solutions for the restricted four-body problem with variable mass. It has been assumed that the three primaries with masses m1, m2 and m3 form an equilateral triangle, wherein m2=m3. According to Jeans' law (Astronomy and Cosmogony, Cambridge University Press, Cambridge, 1928), the infinitesimal body varies its mass m with time. The space-time transformations of Meshcherskii (Studies on the Mechanics of Bodies of Variable Mass, GITTL, Moscow, 1949) are used by taking the values of the parameters q=1/2, k=0, n=1. The equations of motion of the infinitesimal body with variable mass have been determined. The equations of motion of the current problem differ from the ones of the restricted four-body problem with constant mass. There exist eight libration points, out of which two are collinear with the primary m1 and the rest are non-collinear for a fixed value of parameters γ (m {at time} t/m {at initial time}, 0<γ≤1 ), α (the proportionality constant in Jeans' law (Astronomy and Cosmogony, Cambridge University Press, Cambridge, 1928), 0≤α≤2.2) and μ=0.019 (the mass parameter). All the libration points are found to be unstable. The zero velocity surfaces (ZVS) are also drawn and regions of motion are discussed.

A novel approach: chemical relational databases, and the role of the ISSCAN database on assessing chemical carcinogenicity.

PubMed

Benigni, Romualdo; Bossa, Cecilia; Richard, Ann M; Yang, Chihae

2008-01-01

Mutagenicity and carcinogenicity databases are crucial resources for toxicologists and regulators involved in chemicals risk assessment. Until recently, existing public toxicity databases have been constructed primarily as "look-up-tables" of existing data, and most often did not contain chemical structures. Concepts and technologies originated from the structure-activity relationships science have provided powerful tools to create new types of databases, where the effective linkage of chemical toxicity with chemical structure can facilitate and greatly enhance data gathering and hypothesis generation, by permitting: a) exploration across both chemical and biological domains; and b) structure-searchability through the data. This paper reviews the main public databases, together with the progress in the field of chemical relational databases, and presents the ISSCAN database on experimental chemical carcinogens.

Viewing brain processes as Critical State Transitions across levels of organization: Neural events in Cognition and Consciousness, and general principles.

PubMed

Werner, Gerhard

2009-04-01

In this theoretical and speculative essay, I propose that insights into certain aspects of neural system functions can be gained from viewing brain function in terms of the branch of Statistical Mechanics currently referred to as "Modern Critical Theory" [Stanley, H.E., 1987. Introduction to Phase Transitions and Critical Phenomena. Oxford University Press; Marro, J., Dickman, R., 1999. Nonequilibrium Phase Transitions in Lattice Models. Cambridge University Press, Cambridge, UK]. The application of this framework is here explored in two stages: in the first place, its principles are applied to state transitions in global brain dynamics, with benchmarks of Cognitive Neuroscience providing the relevant empirical reference points. The second stage generalizes to suggest in more detail how the same principles could also apply to the relation between other levels of the structural-functional hierarchy of the nervous system and between neural assemblies. In this view, state transitions resulting from the processing at one level are the input to the next, in the image of a 'bucket brigade', with the content of each bucket being passed on along the chain, after having undergone a state transition. The unique features of a process of this kind will be discussed and illustrated.

The Relationship between India’s Geographic Element of Power and its Military Element of Power

DTIC Science & Technology

1991-06-07

provided the background knowledge necessary to begin this project. The Cambridge Encyclopedia of India, Pakistan, BanAladesh and Srilanka , by Francis...and Burma and in the west, by Pakistan. Just south of India’s southern tip lies Srilanka . Location. The bulk of India’s land mass lies between 70...Affairs, (Rand McNally & Co., 1963), 319. 2. Francis Robinson, The Cambridge Encyclopedia of India, Pakistan, Bangladesh, Srilanka , Nepal, Bhutan and

Edge Detection,

DTIC Science & Technology

1985-09-01

PROJECT. T ASK0 Artificial Inteligence Laboratory AREA It WORK UNIT NUMBERS V 545 Technology Square ( Cambridge, HA 02139 I I* CONTOOL1LIN@4OFFICE NAME...ARD-A1t62 62 EDGE DETECTION(U) NASSACNUSETTS INST OF TECH CAMBRIDGE 1/1 ARTIFICIAL INTELLIGENCE LAB E C HILDRETH SEP 85 AI-M-8 N99SI4-8S-C-6595...used to carry out this analysis. cce~iO a N) ’.~" D LI’BL. P p ------------ Sj. t i MASSACHUSETTS INSTITUTE OF TECHNOLOGY i ARTIFICIAL INTELLIGENCE

Using a neural network to proximity correct patterns written with a Cambridge electron beam microfabricator 10.5 lithography system

NASA Astrophysics Data System (ADS)

Cummings, K. D.; Frye, R. C.; Rietman, E. A.

1990-10-01

This letter describes the initial results of using a theoretical determination of the proximity function and an adaptively trained neural network to proximity-correct patterns written on a Cambridge electron beam lithography system. The methods described are complete and may be applied to any electron beam exposure system that can modify the dose during exposure. The patterns produced in resist show the effects of proximity correction versus noncorrected patterns.

Proceedings of the International Symposium on Methodologies for Intelligent Systems (Poster Session) (7th) held at Trondheim, Norway, on 15-18 June, 1993

DTIC Science & Technology

1993-06-18

David Hislop (US Army Research Office), Eero Hyvonen (VTT, Finland), Marek Karpinski (Bonn, Germany), Yves Kodratoff (Paris VI, France), Jan...21] M. P. Marcus, A theory of Syntactic Recognition for Natural Language, The MIT Press, Cambridge, Mass., 1980 [221 K.R. McKeown, The TEXT System...H. Simon, The Sciences of the Artificial, The MIT Press, Cambridge, MA, ( 1980 ). 3. M.D. Mesarovich, D. Macko, Y. Takahara Y., Theory of Hierarchical

An Optimal Dissipative Encoder for the Toric Code

DTIC Science & Technology

2014-01-16

Topological quantummemory J. Math. Phys. 43 4452–505 [6] Diehl S, Micheli A, Kantian A, Kraus B, Büchler H P and Zoller P 2008 Quantum states and phases in...Diehl S, Kantian A, Micheli A and Zoller P 2008 Preparation of entangled states by quantum Markov processes Phys. Rev. A 78 042307 [12] Marvian I 2013...Information Theory (Cambridge: Cambridge University Press) [20] Wolf M and Cirac J I 2008 Dividing quantum channels Commun. Math. Phys. 279 147 11

The Polish Collection at the Alliance College Library in Cambridge Springs, PA: The Origins of the Collection in 1950, Its Rapid Development in the 1970's and the Introduction of the Online Computer Library Center (OCLC) in 1982.

ERIC Educational Resources Information Center

Kozaczka, Stanley J.

This essay outlines the development, present condition, and future direction of the 20,000-volume Polish research collection at Alliance College, located in Cambridge Springs, Pennsylvania. Alliance College was founded in 1912 by the Polish National Alliance (PNA), a life insurance fraternal organization. In 1931 its entire library collection was…

Application of Ada (Trade Name) Higher Order Language to Guidance and Control

DTIC Science & Technology

1986-05-01

name "DoD-0"). The name Ada honors the mathematician of the 19th century who, as colleague to Charles Babbage , developed an instruction set for the as...Avenue St Charles , MO 63301 USA SPEAKERS Mr R.E.Bolz 6751 South Dahlia Court Modem Prograimning Languages Littleton, CO 80122 USA Dr O.Roubine...WHITTREDGE, R. S. PAA : C/( Charles Stark Draper Laboratory, Inc., Cambridge, MA) CORP: Draper ( Charles Stark) Lab., Inc., Cambridge, Mass. IN

Massive Molecular Outflows and Evidence for AGN Feedback from CO Observations

DTIC Science & Technology

2014-01-01

19 J. J. Thomson Avenue, Cambridge CB3 0HE, UK e-mail: c.cicone@mrao.cam.ac.uk 2 Kavli Institute for Cosmology , University of Cambridge, Madingley...about 25 arcsec from the galactic centre (corresponding to 1.6 kpc with the cosmology adopted in this paper). The CO(1–0) integrated flux in this com...power of the molecular outflow as a function of AGN luminosity. Theoretical models of AGN feedback and cosmological simulations predict a coupling effi

Analysis of a Novel Paralogue of SWI/SNF Member p270, Which is Frequently Down-Regulated in Breast Cancer

DTIC Science & Technology

2005-07-01

Viruses and Cell Cycle Control, July 2004, University of Wisconsin, Madison (NCI Travel Award to attend ($750)). "* Norman G. Nagl, Jr., Xiaomei Wang...DNA Tumor Viruses and Cell Cycle Control, July 2002, University of Wisconsin, Madison "* Norman G. Nagl, Jr., Xiaomei Wang, Deborah Wilsker, Michael...Presented at the 2001 Meeting on Small DNA Tumor Viruses and Cell Cycle Control, Cambridge University, Cambridge, UK (NCI Travel Award to attend the 2001

A Tale of Two Countries: Why Some British Muslims Turned to Terrorism and French Muslims Did Not

DTIC Science & Technology

2010-03-01

this protection. Joel S. Fetzer and J. Christopher Soper , Muslims and the State in Britain, France, and Germany. (New York: Cambridge University...Press, 2005), 16. 3 Joel S. Fetzer and J. Christopher Soper , Muslims and the State in Britain, France, and Germany. (New York: Cambridge University...Oxford University Press, 2006), 5. 5 Fetzer and Soper , Muslims and the State, 3. 6 Ibid. 3 This concern developed as they settled permanently in

The 2014 Nucleic Acids Research Database Issue and an updated NAR online Molecular Biology Database Collection.

PubMed

Fernández-Suárez, Xosé M; Rigden, Daniel J; Galperin, Michael Y

2014-01-01

The 2014 Nucleic Acids Research Database Issue includes descriptions of 58 new molecular biology databases and recent updates to 123 databases previously featured in NAR or other journals. For convenience, the issue is now divided into eight sections that reflect major subject categories. Among the highlights of this issue are six databases of the transcription factor binding sites in various organisms and updates on such popular databases as CAZy, Database of Genomic Variants (DGV), dbGaP, DrugBank, KEGG, miRBase, Pfam, Reactome, SEED, TCDB and UniProt. There is a strong block of structural databases, which includes, among others, the new RNA Bricks database, updates on PDBe, PDBsum, ArchDB, Gene3D, ModBase, Nucleic Acid Database and the recently revived iPfam database. An update on the NCBI's MMDB describes VAST+, an improved tool for protein structure comparison. Two articles highlight the development of the Structural Classification of Proteins (SCOP) database: one describes SCOPe, which automates assignment of new structures to the existing SCOP hierarchy; the other one describes the first version of SCOP2, with its more flexible approach to classifying protein structures. This issue also includes a collection of articles on bacterial taxonomy and metagenomics, which includes updates on the List of Prokaryotic Names with Standing in Nomenclature (LPSN), Ribosomal Database Project (RDP), the Silva/LTP project and several new metagenomics resources. The NAR online Molecular Biology Database Collection, http://www.oxfordjournals.org/nar/database/c/, has been expanded to 1552 databases. The entire Database Issue is freely available online on the Nucleic Acids Research website (http://nar.oxfordjournals.org/).

GRAIL Mission Briefing

NASA Image and Video Library

2011-08-25

Maria Zuber, GRAIL principal investigator, Massachusetts Institute of Technology, Cambridge, answers a reporter's question at a press briefing about the upcoming launch to the moon of the Gravity Recovery and Interior Laboratory (GRAIL) mission, Thursday, Aug. 25, 2011 in Washington. GRAIL's primary science objectives are to determine the structure of the lunar interior, from crust to core, and to advance understanding of the thermal evolution of the moon. The mission will place two spacecraft into the same orbit around the moon which will gather information about the its gravitational field enabling scientists to create a high-resolution map. Photo Credit: (NASA/Carla Cioffi)

MMDB: Entrez’s 3D-structure database

PubMed Central

Wang, Yanli; Anderson, John B.; Chen, Jie; Geer, Lewis Y.; He, Siqian; Hurwitz, David I.; Liebert, Cynthia A.; Madej, Thomas; Marchler, Gabriele H.; Marchler-Bauer, Aron; Panchenko, Anna R.; Shoemaker, Benjamin A.; Song, James S.; Thiessen, Paul A.; Yamashita, Roxanne A.; Bryant, Stephen H.

2002-01-01

Three-dimensional structures are now known within many protein families and it is quite likely, in searching a sequence database, that one will encounter a homolog with known structure. The goal of Entrez’s 3D-structure database is to make this information, and the functional annotation it can provide, easily accessible to molecular biologists. To this end Entrez’s search engine provides three powerful features. (i) Sequence and structure neighbors; one may select all sequences similar to one of interest, for example, and link to any known 3D structures. (ii) Links between databases; one may search by term matching in MEDLINE, for example, and link to 3D structures reported in these articles. (iii) Sequence and structure visualization; identifying a homolog with known structure, one may view molecular-graphic and alignment displays, to infer approximate 3D structure. In this article we focus on two features of Entrez’s Molecular Modeling Database (MMDB) not described previously: links from individual biopolymer chains within 3D structures to a systematic taxonomy of organisms represented in molecular databases, and links from individual chains (and compact 3D domains within them) to structure neighbors, other chains (and 3D domains) with similar 3D structure. MMDB may be accessed at http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=Structure. PMID:11752307

HIV Structural Database

National Institute of Standards and Technology Data Gateway

SRD 102 HIV Structural Database (Web, free access)   The HIV Protease Structural Database is an archive of experimentally determined 3-D structures of Human Immunodeficiency Virus 1 (HIV-1), Human Immunodeficiency Virus 2 (HIV-2) and Simian Immunodeficiency Virus (SIV) Proteases and their complexes with inhibitors or products of substrate cleavage.

Validity of the Cambridge Cognitive Examination-Revised new Executive Function Scores in the diagnosis of dementia: some early findings.

PubMed

Heinik, Jeremia; Solomesh, Isaac

2007-03-01

The Cambridge Cognitive Examination-Revised introduces 2 new executive items (Ideational Fluency and Visual Reasoning), which separately or combined with 2 executive items in the former version (word list generation and similarities) might constitute an Executive Function Score (EFS). The authors studied the validity of these new EFSs in 51 demented (dementia of the Alzheimer's type, vascular dementia) and nondemented individuals (depressives and normals). The new EFSs were found valid to accurately differentiate between demented and nondemented subjects; however, they were considerably less so when specific diagnoses were considered. Correlations between the variously combined executive scores and the cognitive scales and subscales studied were prevalently low to moderate, and ranged from high and significant to low and nonsignificant when the 4 executive items were correlated to each other. The ability of the executive scores to discriminate demented from nondemented individuals was lower compared with the Cambridge Cognitive Examination-Revised scores. EFS was found internally consistent.

How the Weak Variance of Momentum Can Turn Out to be Negative

NASA Astrophysics Data System (ADS)

Feyereisen, M. R.

2015-05-01

Weak values are average quantities, therefore investigating their associated variance is crucial in understanding their place in quantum mechanics. We develop the concept of a position-postselected weak variance of momentum as cohesively as possible, building primarily on material from Moyal (Mathematical Proceedings of the Cambridge Philosophical Society, Cambridge University Press, Cambridge, 1949) and Sonego (Found Phys 21(10):1135, 1991) . The weak variance is defined in terms of the Wigner function, using a standard construction from probability theory. We show this corresponds to a measurable quantity, which is not itself a weak value. It also leads naturally to a connection between the imaginary part of the weak value of momentum and the quantum potential. We study how the negativity of the Wigner function causes negative weak variances, and the implications this has on a class of `subquantum' theories. We also discuss the role of weak variances in studying determinism, deriving the classical limit from a variational principle.

The linguistically aware teacher and the teacher-aware linguist.

PubMed

McCartney, Elspeth; Ellis, Sue

2013-07-01

This review evaluates issues of teacher linguistic knowledge relating to their work with children with speech, language and communication difficulties (SLCD). Information is from Ellis and McCartney [(2011a). Applied linguistics and primary school teaching. Cambridge: Cambridge University Press], a state-of-the-art text deriving from a British Association of Applied Linguistics/Cambridge University Press expert seminar series that details: linguistic research underpinning primary school curricula and pedagogy; the form of linguistic knowledge useful for teachers supporting children with SLCD in partnership with speech and language therapists; and how and when teachers acquire and learn to apply such knowledge. Critical analysis of the options presented for teacher learning indicate that policy enjoinders now include linguistic application as an expected part of teachers' professional knowledge, for all children including those with SLCD, but there is a large unmet learning need. It is concluded that there is a role for clinical linguists to disseminate useable knowledge to teachers in an accessible format. Ways of achieving this are considered.

Taxonomic notes on the crab spider genera Stephanopoides and Isaloides (Araneae: Thomisidae: Stephanopinae).

PubMed

Teixeira, Renato Augusto; Barros, Bruno Augusto Reis

2015-05-08

According to current catalogues, two species are allocated to the genus Parastephanops F. O. Pickard-Cambridge, 1900. The examination of the type of Parastephanops cognatus (O. Pickard-Cambridge, 1892) (type-species of Parastephanops) has revealed the presence of a high cephalic region, legs with dark metatarsus and apex of tibia, and triangular epigynum with median ridge, all diagnostic features of Stephanopoides Keyserling, 1880. However, the female of P. echinatus (Banks, 1914) has a low cephalic region, a median ocular quadrangle longer than wide and a large atrium of the epigynum, which are diagnostic features of Isaloides F. O. Pickard-Cambridge, 1900. Thus, Parastephanops is synonymized with Stephanopoides and its two species, P. cognatus and P. echinatus, are redescribed, illustrated and assigned to Stephanopoides and Isaloides, respectively. We also propose that Pyresthesis berlandi Caporiacco, 1947 is a junior synonym of Stephanopoides simoni Keyserling, 1880 based on shape and arrangement of the epigynal plate, copulatory ducts and spermathecae.

Diagnosis of mild chronic pancreatitis (Cambridge classification): comparative study using secretin injection-magnetic resonance cholangiopancreatography and endoscopic retrograde pancreatography.

PubMed

Sai, Jin-Kan; Suyama, Masafumi; Kubokawa, Yoshihiro; Watanabe, Sumio

2008-02-28

To investigate the usefulness of secretin injection-MRCP for the diagnosis of mild chronic pancreatitis. Sixteen patients having mild chronic pancreatitis according to the Cambridge classification and 12 control subjects with no abnormal findings on the pancreatogram were examined for the diagnostic accuracy of secretin injection-MRCP regarding abnormal branch pancreatic ducts associated with mild chronic pancreatitis (Cambridge Classification), using endoscopic retrograde cholangiopancreatography (ERCP) for comparison. The sensitivity and specificity for abnormal branch pancreatic ducts determined by two reviewers were respectively 55%-63% and 75%-83% in the head, 57%-64% and 82%-83% in the body, and 44%-44% and 72%-76% in the tail of the pancreas. The sensitivity and specificity for mild chronic pancreatitis were 56%-63% and 92%-92%, respectively. Interobserver agreement (kappa statistics) concerning the diagnosis of an abnormal branch pancreatic duct and of mild chronic pancreatitis was good to excellent. Secretin injection-MRCP might be useful for the diagnosis of mild chronic pancreatitis.

A natural history of mathematics: George Peacock and the making of English algebra.

PubMed

Lambert, Kevin

2013-06-01

In a series of papers read to the Cambridge Philosophical Society through the 1820s, the Cambridge mathematician George Peacock laid the foundation for a natural history of arithmetic that would tell a story of human progress from counting to modern arithmetic. The trajectory of that history, Peacock argued, established algebraic analysis as a form of universal reasoning that used empirically warranted operations of mind to think with symbols on paper. The science of counting would suggest arithmetic, arithmetic would suggest arithmetical algebra, and, finally, arithmetical algebra would suggest symbolic algebra. This philosophy of suggestion provided the foundation for Peacock's "principle of equivalent forms," which justified the practice of nineteenth-century English symbolic algebra. Peacock's philosophy of suggestion owed a considerable debt to the early Cambridge Philosophical Society culture of natural history. The aim of this essay is to show how that culture of natural history was constitutively significant to the practice of nineteenth-century English algebra.

An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system.

PubMed

AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide

2015-11-19

Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database in which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. This database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.

Conflict in the Cosmos: the Hoyle-Ryle clashes

NASA Astrophysics Data System (ADS)

Mitton, S.

2005-08-01

Fred Hoyle (1915-2001) made great contributions to both astrophysics and cosmology. His work in accretion theory (1939-45) and nuclear astrophysics (1946-57) continues to be admired and widely quoted. In cosmology, the field for which he is best known among the general public, his achievement is more questionable and marked by controversy. He was the first to use the expression Big Bang to describe the evolving universes of Eddington, Lemaitre, and Gamow. He named his own theory Continuous Creation, although the expression Steady State, coined by Bondi and Gold, became associated with Hoyle's model of a universe of infinite age, infinite extent, and matter creation. By 1952 the Cambridge radio astronomer Martin Ryle (1918-84) realised that his group could join the observational cosmology game. They would use counts of radio sources to discriminate between evolution and steady state. Ryle's first two surveys were inadequate and unreliable, although he did not see it that way, believing from the outset that he had proved Hoyle wrong. The third and fourth surveys did point to an evolutionary universe, but Hoyle refused to accept this, given Ryle's earlier track record in observational cosmology. The two argued passionately for a period of 20 years in a way that came to do serious harm to the standing of astronomy in the University of Cambridge. The paper examines the reasons for the failure of the two Cambridge astronomers to be more co-operative. This research was supported by St Edmund's College, Cambridge.

Hamming's "open doors" and group creativity as keys to scientific excellence: the example of Cambridge.

PubMed

Erren, Thomas C

2008-01-01

Dr. Charlton used diverse approaches to identify research institutions which provided home to outstanding scientists and work. One intriguing example of long-lasting scientific excellence is Cambridge with 19 Nobel laureates who worked at the University or at the MRC Molecular Biology Unit when they received the prize between 1947 and 2006. With specific reference to Cambridge, I would like to complement the primarily quantitative assessment and offer considerations as to why and how research achievements may have clustered in space and time. Indeed, observations voiced by the mathematician Richard Hamming as to how great research can be pursued offer explanations for the series of great science in the UK. In my view, the most important determinant of the clustering may be illustrated by Hamming's fitting picture of "open doors": working in environments with the doors open allows constant interactions with peers with various disciplinary backgrounds, and thus fast avoidance of detours or dead ends in science and, ultimately, a focus on and the solution of problems of paramount, rather than of tangential, importance. Narrative insights into a strong argumentative tradition at Cambridge provided by Drs. Watson and Magueijo between 1968 and 2003 are in line with Hamming's suggestion and the value of group creativity. In the internet age with abundant interactions beyond home institutions we should not be surprised if clusters of great science were no longer confined to the usual suspect institutions which were awarded disproportionally with Nobel prizes in the past.

The Cambridge-Cambridge x-ray serendipity survey. 2: Classification of x-ray luminous galaxies

NASA Technical Reports Server (NTRS)

Boyle, B. J.; Mcmahon, R. G.; Wilkes, B. J.; Elvis, Martin

1994-01-01

We present the results of an intermediate-resolution (1.5 A) spectroscopic study of 17 x-ray luminous narrow emission-line galaxies previously identified in the Cambridge-Cambridge ROSAT Serendipity Survey and the Einstein Extended Medium Sensitivity Survey. Emission-line ratios reveal that the sample is composed of ten Seyfert and seven starburst galaxies. Measured linewidths for the narrow H alpha emission lines lie in the range 170 - 460 km s(exp -1). Five of the objects show clear evidence for asymmetry in the (OIII) lambda 5007 emission-line profile. Broad H alpha emission is detected in six of the Seyfert galaxies, which range in type from Seyfert 1.5 to 2. Broad H beta emission is only detected in one Seyfert galaxy. The mean full width at half maximum for the broad lines in the Seyfert galaxies is FWHM = 3900 +/- 1750 km s(exp -1). Broad (FWHM = 2200 +/- 600 km s(exp -1) H alpha emission is also detected in three of the starburst galaxies, which could originate from stellar winds or supernovae remnants. The mean Balmer decrement for the sample is H alpha / H beta = 3, consistent with little or no reddening for the bulk of the sample. There is no evidence for any trend with x-ray luminosity in the ratio of starburst galaxies to Seyfert galaxies. Based on our previous observations, it is therefore likely that both classes of object comprise approximately 10 percent of the 2 keV x-ray background.

Tautomerism in chemical information management systems

NASA Astrophysics Data System (ADS)

Warr, Wendy A.

2010-06-01

Tautomerism has an impact on many of the processes in chemical information management systems including novelty checking during registration into chemical structure databases; storage of structures; exact and substructure searching in chemical structure databases; and depiction of structures retrieved by a search. The approaches taken by 27 different software vendors and database producers are compared. It is hoped that this comparison will act as a discussion document that could ultimately improve databases and software for researchers in the future.

Columba: an integrated database of proteins, structures, and annotations.

PubMed

Trissl, Silke; Rother, Kristian; Müller, Heiko; Steinke, Thomas; Koch, Ina; Preissner, Robert; Frömmel, Cornelius; Leser, Ulf

2005-03-31

Structural and functional research often requires the computation of sets of protein structures based on certain properties of the proteins, such as sequence features, fold classification, or functional annotation. Compiling such sets using current web resources is tedious because the necessary data are spread over many different databases. To facilitate this task, we have created COLUMBA, an integrated database of annotations of protein structures. COLUMBA currently integrates twelve different databases, including PDB, KEGG, Swiss-Prot, CATH, SCOP, the Gene Ontology, and ENZYME. The database can be searched using either keyword search or data source-specific web forms. Users can thus quickly select and download PDB entries that, for instance, participate in a particular pathway, are classified as containing a certain CATH architecture, are annotated as having a certain molecular function in the Gene Ontology, and whose structures have a resolution under a defined threshold. The results of queries are provided in both machine-readable extensible markup language and human-readable format. The structures themselves can be viewed interactively on the web. The COLUMBA database facilitates the creation of protein structure data sets for many structure-based studies. It allows to combine queries on a number of structure-related databases not covered by other projects at present. Thus, information on both many and few protein structures can be used efficiently. The web interface for COLUMBA is available at http://www.columba-db.de.

Out-of-equilibrium processes in suspensions of oppositely charged colloids: liquid-to-crystal nucleation and gel formation

NASA Astrophysics Data System (ADS)

Sanz, Eduardo

2009-03-01

We study the kinetics of the liquid-to-crystal transformation and of gel formation in colloidal suspensions of oppositely charged particles. We analyse, by means of both computer simulations and experiments, the evolution of a fluid quenched to a state point of the phase diagram where the most stable state is either a homogeneous crystalline solid or a solid phase in contact with a dilute gas. On the one hand, at high temperatures and high packing fractions, close to an ordered-solid/disordered-solid coexistence line, we find that the fluid-to-crystal pathway does not follow the minimum free energy route. On the other hand, a quench to a state point far from the ordered-crystal/disordered-crystal coexistence border is followed by a fluid-to-solid transition through the minimum free energy pathway. At low temperatures and packing fractions we observe that the system undergoes a gas-liquid spinodal decomposition that, at some point, arrests giving rise to a gel-like structure. Both our simulations and experiments suggest that increasing the interaction range favors crystallization over vitrification in gel-like structures. [4pt] In collaboration with Chantal Valeriani, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands and SUPA, School of Physics, University of Edinburgh, JCMB King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, UK; Teun Vissers, Andrea Fortini, Mirjam E. Leunissen, and Alfons van Blaaderen, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University; Daan Frenke, FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJ Amsterdam, The Netherlands and Department of Chemistry, University of Cambridge, Lensfield Road, CB2 1EW, Cambridge, UK; and Marjolein Dijkstra, Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University.

Electromagnetic Studies Using The Cam-1 (lisbon-madeira) Submarine Cable

NASA Astrophysics Data System (ADS)

Monteiro Santos, F.; Soares, A.; Rodrigues, H.; Luzio, R.; Nolasco, R.; Iso-3D Team

Data of electrical voltage measured between the ends of the CAM-1 cable have been analysed in order to determine the electrical stability of the cable and to obtain some preliminary information related to water transport. The monthly average of the po- tential measured during days with low geomagnetic activity suggests a periodicity of 120 days that was tentatively interpreted as having origin in water flow. These results show a small trend that is compatible with no drift in the cable. The mean electric field estimated from quiet days is 0.206 s´ 0.022 mV/km. The voltage measurements have been used, in combination with magnetic observations carried out in the geomagnetic observatory of Guimar (Canary Islands), to estimate the deep geoelectrical structure beneath the ocean. Apparent resistivities and phases were calculated from those data sets. Magnetic transfer function (tipper) measured in two long period (magnetovari- ational) stations located near the coast line, and the invariant apparent resistivity and phase obtained at one site in SW Iberia were used in the modelling in order to bet- ter constraint some model parameters. The result obtained by one- two- and three- dimensional trial-and-error modelling suggests a three-layer geoelectrical structure beneath the ocean. The conductance of the uppermost layer, representing sea-water and marine sediments, is most likely in the range between 15700 and 18500 S. The most probable order of the integral resistivity of the lithosphere layer in marine part is 4x107 ohm m2. ISO-3D team: M. Sinha (U. Cambridge/U. Southampton), J.M. Miranda (CGUL), A. Junge (U. Frankfurt), A. Flosadottir (HALO), N. Lourenço and J. Luís (U. Algarve), L. MacGregor, S. Dean, N. Barker, S. Riches and Z. Cheng (U. Cambridge/U. Southamp- ton).

Internal consistency and stability of the CANTAB neuropsychological test battery in children.

PubMed

Syväoja, Heidi J; Tammelin, Tuija H; Ahonen, Timo; Räsänen, Pekka; Tolvanen, Asko; Kankaanpää, Anna; Kantomaa, Marko T

2015-06-01

The Cambridge Neuropsychological Test Automated Battery (CANTAB) is a computer-assessed test battery widely use in different populations. The internal consistency and 1-year stability of CANTAB tests were examined in school-age children. Two hundred-thirty children (57% girls) from five schools in the Jyväskylä school district in Finland participated in the study in spring 2011. The children completed the following CANTAB tests: (a) visual memory (pattern recognition memory [PRM] and spatial recognition memory [SRM]), (b) executive function (spatial span [SSP], Stockings of Cambridge [SOC], and intra-extra dimensional set shift [IED]), and (c) attention (reaction time [RTI] and rapid visual information processing [RVP]). Seventy-four children participated in the follow-up measurements (64% girls) in spring 2012. Cronbach's alpha reliability coefficient was used to estimate the internal consistency of the nonhampering test, and structural equation models were applied to examine the stability of these tests. The reliability and the stability could not be determined for IED or SSP because of the nature of these tests. The internal consistency was acceptable only in the RTI task. The 1-year stability was moderate-to-good for the PRM, RTI, and RVP. The SSP and IED showed a moderate correlation between the two measurement points. The SRM and the SOC tasks were not reliable or stable measures in this study population. For research purposes, we recommend using structural equation modeling to improve reliability. The results suggest that the reliability and the stability of computer-based test batteries should be confirmed in the target population before using them for clinical or research purposes. (c) 2015 APA, all rights reserved).

PREFACE: International Conference on Strongly Correlated Electron Systems (SCES 2011)

NASA Astrophysics Data System (ADS)

Littlewood, P. B.; Lonzarich, G. G.; Saxena, S. S.; Sutherland, M. L.; Sebastian, S. E.; Artacho, E.; Grosche, F. M.; Hadzibabic, Z.

2012-11-01

The Strongly Correlated Electron Systems Conference (SCES) 2011, was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 was dedicated to 100 years of superconductivity and covered a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The meeting welcomed to Cambridge 657 participants from 23 countries, who presented 127 talks (including 16 plenary, 57 invited, and 54 contributed) and 736 posters in 40 sessions over five full days of meetings. This proceedings volume contains papers reporting on the science presented at the meeting. This work deepens our understanding of the rich physical phenomena that arise from correlation effects. Strongly correlated systems are known for their remarkable array of emergent phenomena: the traditional subjects of superconductivity, magnetism and metal-insulator transitions have been joined by non-Fermi liquid phenomena, topologically protected quantum states, atomic and photonic gases, and quantum phase transitions. These are some of the most challenging and interesting phenomena in science. As well as the science driver, there is underlying interest in energy-dense materials, which make use of 'small' electrons packed to the highest possible density. These are by definition 'strongly correlated'. For example: good photovoltaics must be efficient optical absorbers, which means that photons will generate tightly bound electron-hole pairs (excitons) that must then be ionised at a heterointerface and transported to contacts; efficient solid state refrigeration depends on substantial entropy changes in a unit cell, with large local electrical or magnetic moments; efficient lighting is in a real sense the inverse of photovoltaics; the limit of an efficient battery is a supercapacitor employing mixed valent ions; fuel cells and solar to fuel conversion require us to understand electrochemistry on the scale of a single atom; and we already know that the only prospect for effective high temperature superconductivity involves strongly correlated materials. Even novel IT technologies are now seen to have value not just for novel function but also for efficiency. While strongly correlated electron systems continue to excite researchers and the public alike due to the fundamental science issues involved, it seems increasingly likely that support for the science will be leveraged by its impact on energy and sustainability. The conference owes its success to the large number of devoted workers for the cause, which includes the organising and programme committees and a considerable number of workers on the ground who contributed to the smooth running of the meeting. The conference received major sponsorship from CamCool Research Limited, the International Institute for Complex Adaptive Matter, from the European Science Foundation through the program INTELBIOMAT, and the Cambridge Central Asia Forum. On behalf of Conference Chairs: P B Littlewood and G G Lonzarich Secretary: S Saxena Treasurer: M Sutherland Local Organising Committee Chair: S E Sebastian Programme Committee Chairs: E Artacho, F M Grosche, Z Hadzibabic (The PDF file also contains photographs from the conference.) Programme Committee E. Artacho, Cambridge (chair)D. Cox, DavisM. Norman, Argonne M. Grosche, Cambridge (chair)H. Ding, IOP, ChinaY. Onuki, Osaka Z. Hadzibabic, Cambridge (chair)M. Ellerby, LondonC. Panagopoulos, Singapore H. Alloul, Paris Z. Fisk, IrvineS. Ramakrishnan, Mumbai E. Baggio-Saitovich, Rio Di JaneiroJ. Flouquet, GrenobleA. Ramirez, Santa Cruz E. Bauer, ViennaA. Galatanu, RomaniaF. Rivadulla, Compostela N. Berloff, CambridgeP. Gegenwart, GottingenS. E. Sebastian, Cambridge D. Bonn, VancouverL. Greene, UrbanaV. Sechovsky, Prague J. van den Brink, DresdenH. Hwang, TokyoS. Simon, Oxford R. Budhani, DelhiA. P. Mackenzie, St.AndrewsD. Snoke, Pittsburgh P. Chandra, PiscatawayN. Mathur, CambridgeJ.C. Gomez-Sal, Santander S-W. Cheong, RutgersK. Miyake, OsakaV. Tripathi, Mumbai P. Coleman, PiscatawayA Navrotsky, DavisA. Vasiliev, Moscow M. Vojta, Cologne Local Committee S. E. Sebastian (chair)R. NeedsJ. Keeling N. MathurE. PughD. Khmelnitskii M. ParishM. CarpenterM. Koehl M. AtatureR. CowburnW. Milne C. BarnesJ. McManus DriscollS. Redfern N. BerloffA. FerrariD. Ritchie M. BlamireC. GreyJ. Robertson J. BaumbergZ. HadzibabicB. Simons A. Cheetham National Advisory Committee G. Aeppli, LondonV. Falko, LancasterM. Pepper, Cambridge A. Ardavan, OxfordR. Friend, CambridgeT. Perring, Didcot P. Attfield, EdinburghC. Frost, RutherfordJ. Saunders, London A. Boothroyd, OxfordG. Gehring, ShefieldA. Schofield, Birmingham A. Coldea, OxfordS. Hayden, BristolN. Shannon, Bristol L. Eaves, NottinghamN. Hussey, BristolM. Skolnick, Sheffield D. Edwards, LondonA. Huxley, EdinburghS. Thompson, York M. Ellerby, LondonH. Wilhelm, Didcot International Advisory Committee E. Abrahams, UCLAG. Kotliar, Piscataway E. V. Sampathkumaran, Mumbai G. Aeppli, LondonD. Khmelnitskii, CambridgeUK J. Sarrao, Los Alamos J. W. Allen, Ann ArborK. Kugel, MoscowJ. Schilling, St. Louise P. W. Anderson, Princeton C. Lacroix, Grenoble A. Schofield, Birmingham M. Aronson, Stony Brook P. A. LeeCambridge, USA V. Sechovsky, Prague Y. K. Bang, Kwangju and Pohang C.T. Liang, Taipei T. Senthil, Cambridge, USA M. Barma, Mumbai P. Majumdar, Allahabad J. G. Sereni, Bariloche G. Baskaran, Chennai Y. Maeno, Kyoto K. Shimizu, Osaka E. Bauer, Vienna J. Mannhart, Augsburg Q. Si, Houston G. Boebinger, Tallahassee M. B. Maple, San Diego M. Sigrist, Zurich R. Budhani, Delhi Y. Matsuda, Kyoto A. Simoni, Trento P. Canfield, Ames R. Moessner, Dresden D. Singh, Oak Ridge M. Continentino, Rio di Janiero A. Millis, New York A. Sood, Bangalore S. Coppersmith, Madison J. Mydosh, Leiden J. Spalek, Krakow B. Coqblin, Paris S. Nakatsuji, Tokyo F. Steglich, Dresden A. Chubukov, Madison G. Oomi, Kyushu G. R. Stewart, Gainesville C. Di Castro, Rome R. Osborn, Chicago H. Takagi, Tokyo M. Eremets, Mainz S. Ovchnikov, Krasnoyarsk L. Taillefer, Sherbrooke M. Fiebig, Bonn C. Panagopoulos, Singapore & Heraklion J. D. Thompson, Los Alamos Z. FiskIrvine S. Paschen, Vienna Y. Tokura, Tokyo J. Flouquet, Grenoble C. Pfleiderer, Munich K. Ueda, Tokyo P. Fulde, Dresden P. Phillips, Urbana C. M. Varma, Riverside A. Geim, Manchester D. Pines, Davis T. Vojta, Rolla J.C. Gomez-Sal, Santander T. V. Ramakrishnan, Bangalore N.L. Wang, Beijing A. Kavokin, Southampton A.K. Raychaudhuri, Calcutta T. Xiang, Beijing J. Goodenough, Austin M. Reifers, Kosice L. Yu, Beijing H. Hosono, Tokyo P. Riseborough, Philadelphia F. C. Zhang, Hong Kong S. Julian, Toronto M. L Saboungi, Orleans G. Zwicknagl, Braunschweig Operational Team Anson Cheung (co-ordinator)Hyeong Jin KimPaul Nahai-Williamson Beng Tan (co-ordinator)Jack GillettPeter Logg Cheng Liu (co-ordinator)Jo WensleyPrajakti Kalra Swee K. Goh (co-ordinator)Jonathan SilverRichard Brierley Adam HalskiLara SibleyRobert Hay Edd CavannaLeona HopeSeb Haines Felix NissenLina KlintbergSitikantha Das Gareth ConduitMarianne BauerStephen Rowley Gerie LonzarichMatt BurgessSven Friedemann Greg LeverMuhammad Ahsan ZebYang Zou Hannah PriceNick BristoweYiqian Xu Haruka TaniguchiOleksandr PoplavskyyZhuo Feng

Symmetric functionalization of polyhedral phenylsilsesquioxanes as a route to nano-building blocks

NASA Astrophysics Data System (ADS)

Roll, Mark Francis

The design and synthesis of nanometer scale structures is of intense current interest. Herein we report on the ability to use symmetric, robust, mutable silsesquioxane ([RSiO3/2]n) nano-building blocks to produce well-defined 3-D structures for electronic or adsorption applications. We are able to show the systematic effects of supermolecular coordination to modulate the density of the molecular packing. This dissertation first describes the synthesis of the elusive decaphenylsilsesquioxane, and the exploration of the substitutionally specific para iodination of the octa-, deca- and dodeca-(p-iodophenyl)-silsesquioxanes, whose single-crystal X-ray diffraction structures are reported. Octa( p-iodophenyl)-silsesquioxane shows supermolecular coordination via Desiraju's halogen-halogen short-contact synthon, forming an open structure with a solvent accessible cavity comprising 40% of the unit cell. The application of palladium, nickel and copper catalyzed cross-coupling techniques using the carbon-iodine bond is explored in order to divergently synthesize crystalline derivatives. These derivatives include the octa(diphenylacetylene)-silsesquioxane and the octa(hexaphenylbenzene)silsesquioxane (56 Aryl), whose single-crystal X-ray diffraction structures are reported. We show that 56 Aryl, which contains more carbon atoms than any other discrete molecule in the Cambridge Structural Database, crystallizes into an extremely open structure with a solvent accessible cavity comprising 55% of the total volume. The supermolecular ordering driven by the bulky hexaphenylbenzene moieties gives nanometer-scale channels along the ab plane. Substitutional specificity is explored in the bromination of octaphenylsilsesquioxane (OPS), and single-crystal X-ray diffraction structures are reported for the octa-, hexadeca- and tetraicosa-brominated derivatives. Precise synthetic control is demonstrated by the unique catalyst-free bromination of OPS, providing the octa(o-bromophenyl)-silsesquioxane in low yield. An iron tribromide catalyzed hexadeca-bromination gives the crystalline octa(2,5-dibromopheny1)silsesquioxane in good yield, with a high density of 2.3 g/cc. Finally, the iron tribromide-catalyzed tetraicosa-bromination of OPS is described, producing a low yield of crystals with a solid solution of substitution patterns coordinated by bromine-bromine short contacts. Lastly, the Scholl-type, dehydrogenative cyclization of the octa(hexaarylbenzene)silsesquioxane systems is explored by the addition of iron trichloride/nitromethane to a refluxing solution of the silsesquioxane in stannic chloride/dichloromethane. The products are analyzed by Proton Nuclear Magnetic Resonance Spectroscopy, Matrix Assisted Laser Desorption and Ionization - Time of Flight Mass Spectroscopy and Diffuse Reflectance Fourier Transform Infra Red Spectroscopy.

Active Contours for Multispectral Images With Non-Homogeneous Sub-Regions

DTIC Science & Technology

2005-09-16

Marching Methods. Cambridge Monographs on Applied and Computational Mathematics, Cambridge University Press, 2nd ed., 1999. [76] R . Malladi and J. Sethian...F. Dibos, “A geometric model for active contours,” Numerische Mathematik, p. 19, 1993. [80] R . Malladi , J. Sethian, and C. Vemuri, “Shape modeling... Malladi et al. [80, 76] proposed a similar model given by ∂φ(x, y) ∂t = g(I(x, y))(κ(φ(x, y)) + ν)|∇φ(x, y)|, (3.14) where g(·) : Ω → < denotes the

Merging Multiple-Partial-Depth Data Time Series Using Objective Empirical Orthogonal Function Fitting

DTIC Science & Technology

2010-05-01

F. J. Lermusiaux, “Adaptive modeling, adaptive data assimilation and adaptive sampling,” Physica D, vol. 230, pp. 172–196, 2007 . [9] T. P. Sapsis and...DOI: 10.1016/j.physd.2009.09.017. [10] P. F. J. Lermusiaux, P. Malanotte-Rizzoli, D. Stammer , J. Carton, J. Cummings, and A. M. Moore, “Progress and...Oceanography, vol. 20, pp. 156–167, 2007 . [12] C. Wunsch, The Ocean Circulation Inverse Problem. Cambridge, U.K.: Cambridge Univ. Press, 1996, ch. 3. [13] H

Experimental and theoretical evidence of a supercritical-like transition in an organic semiconductor presenting colossal uniaxial negative thermal expansion† †Electronic supplementary information (ESI) available: Diffraction and crystallography, Cambridge Structural Database survey, DFT computational details, UV spectroscopy, differential scanning calorimetry, and optical microscopy. CCDC 1810678–1810688. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c8sc00159f

PubMed Central

Roche, Gilles H.; Wantz, Guillaume; Moreau, Joël J. E.; Dautel, Olivier J.; Filhol, Jean-Sébastien

2018-01-01

Thermal expansion coefficients of most materials are usually small, typically up to 50 parts per million per kelvin, and positive, i.e. materials expand when heated. Some materials show an atypical shrinking behavior in one or more crystallographic directions when heated. Here we show that a high mobility thiophene-based organic semiconductor, BHH-BTBT, has an exceptionally large negative expansion between 95 and 295 K (–216 < α2 = αb < –333 MK–1), being compensated by an even larger positive expansion in the perpendicular direction (287 < α1 < 634 MK–1). It is shown that these anomalous expansivities are completely absent in C8-BTBT, a much studied organic semiconductor with a closely related molecular formula and 3D crystallographic structure. Complete theoretical characterization of BHH-BTBT using ab initio molecular dynamics shows that below ∼200 K two different α and β domains exist of which one is dominant but which dynamically exchange around and above 210 K. A supercritical-like transition from an α dominated phase to a β dominated phase is observed using DSC measurements, UV-VIS spectroscopy, and X-ray diffraction. The origin of the extreme negative and positive thermal expansion is related to steric hindrance between adjacent tilted thiophene units and strongly enhanced by attractive S···S and S···C interactions within the highly anharmonic mixed-domain phase. This material could trigger the tailoring of optoelectronic devices highly sensitive to strain and temperature. PMID:29780527

E-MSD: an integrated data resource for bioinformatics.

PubMed

Velankar, S; McNeil, P; Mittard-Runte, V; Suarez, A; Barrell, D; Apweiler, R; Henrick, K

2005-01-01

The Macromolecular Structure Database (MSD) group (http://www.ebi.ac.uk/msd/) continues to enhance the quality and consistency of macromolecular structure data in the worldwide Protein Data Bank (wwPDB) and to work towards the integration of various bioinformatics data resources. One of the major obstacles to the improved integration of structural databases such as MSD and sequence databases like UniProt is the absence of up to date and well-maintained mapping between corresponding entries. We have worked closely with the UniProt group at the EBI to clean up the taxonomy and sequence cross-reference information in the MSD and UniProt databases. This information is vital for the reliable integration of the sequence family databases such as Pfam and Interpro with the structure-oriented databases of SCOP and CATH. This information has been made available to the eFamily group (http://www.efamily.org.uk/) and now forms the basis of the regular interchange of information between the member databases (MSD, UniProt, Pfam, Interpro, SCOP and CATH). This exchange of annotation information has enriched the structural information in the MSD database with annotation from wider sequence-oriented resources. This work was carried out under the 'Structure Integration with Function, Taxonomy and Sequences (SIFTS)' initiative (http://www.ebi.ac.uk/msd-srv/docs/sifts) in the MSD group.

Using the structure-function linkage database to characterize functional domains in enzymes.

PubMed

Brown, Shoshana; Babbitt, Patricia

2014-12-12

The Structure-Function Linkage Database (SFLD; http://sfld.rbvi.ucsf.edu/) is a Web-accessible database designed to link enzyme sequence, structure, and functional information. This unit describes the protocols by which a user may query the database to predict the function of uncharacterized enzymes and to correct misannotated functional assignments. The information in this unit is especially useful in helping a user discriminate functional capabilities of a sequence that is only distantly related to characterized sequences in publicly available databases. Copyright © 2014 John Wiley & Sons, Inc.

LMSD: LIPID MAPS structure database

PubMed Central

Sud, Manish; Fahy, Eoin; Cotter, Dawn; Brown, Alex; Dennis, Edward A.; Glass, Christopher K.; Merrill, Alfred H.; Murphy, Robert C.; Raetz, Christian R. H.; Russell, David W.; Subramaniam, Shankar

2007-01-01

The LIPID MAPS Structure Database (LMSD) is a relational database encompassing structures and annotations of biologically relevant lipids. Structures of lipids in the database come from four sources: (i) LIPID MAPS Consortium's core laboratories and partners; (ii) lipids identified by LIPID MAPS experiments; (iii) computationally generated structures for appropriate lipid classes; (iv) biologically relevant lipids manually curated from LIPID BANK, LIPIDAT and other public sources. All the lipid structures in LMSD are drawn in a consistent fashion. In addition to a classification-based retrieval of lipids, users can search LMSD using either text-based or structure-based search options. The text-based search implementation supports data retrieval by any combination of these data fields: LIPID MAPS ID, systematic or common name, mass, formula, category, main class, and subclass data fields. The structure-based search, in conjunction with optional data fields, provides the capability to perform a substructure search or exact match for the structure drawn by the user. Search results, in addition to structure and annotations, also include relevant links to external databases. The LMSD is publicly available at PMID:17098933

Ambiguity of non-systematic chemical identifiers within and between small-molecule databases.

PubMed

Akhondi, Saber A; Muresan, Sorel; Williams, Antony J; Kors, Jan A

2015-01-01

A wide range of chemical compound databases are currently available for pharmaceutical research. To retrieve compound information, including structures, researchers can query these chemical databases using non-systematic identifiers. These are source-dependent identifiers (e.g., brand names, generic names), which are usually assigned to the compound at the point of registration. The correctness of non-systematic identifiers (i.e., whether an identifier matches the associated structure) can only be assessed manually, which is cumbersome, but it is possible to automatically check their ambiguity (i.e., whether an identifier matches more than one structure). In this study we have quantified the ambiguity of non-systematic identifiers within and between eight widely used chemical databases. We also studied the effect of chemical structure standardization on reducing the ambiguity of non-systematic identifiers. The ambiguity of non-systematic identifiers within databases varied from 0.1 to 15.2 % (median 2.5 %). Standardization reduced the ambiguity only to a small extent for most databases. A wide range of ambiguity existed for non-systematic identifiers that are shared between databases (17.7-60.2 %, median of 40.3 %). Removing stereochemistry information provided the largest reduction in ambiguity across databases (median reduction 13.7 percentage points). Ambiguity of non-systematic identifiers within chemical databases is generally low, but ambiguity of non-systematic identifiers that are shared between databases, is high. Chemical structure standardization reduces the ambiguity to a limited extent. Our findings can help to improve database integration, curation, and maintenance.

Molecule database framework: a framework for creating database applications with chemical structure search capability

PubMed Central

2013-01-01

Background Research in organic chemistry generates samples of novel chemicals together with their properties and other related data. The involved scientists must be able to store this data and search it by chemical structure. There are commercial solutions for common needs like chemical registration systems or electronic lab notebooks. However for specific requirements of in-house databases and processes no such solutions exist. Another issue is that commercial solutions have the risk of vendor lock-in and may require an expensive license of a proprietary relational database management system. To speed up and simplify the development for applications that require chemical structure search capabilities, I have developed Molecule Database Framework. The framework abstracts the storing and searching of chemical structures into method calls. Therefore software developers do not require extensive knowledge about chemistry and the underlying database cartridge. This decreases application development time. Results Molecule Database Framework is written in Java and I created it by integrating existing free and open-source tools and frameworks. The core functionality includes: • Support for multi-component compounds (mixtures) • Import and export of SD-files • Optional security (authorization) For chemical structure searching Molecule Database Framework leverages the capabilities of the Bingo Cartridge for PostgreSQL and provides type-safe searching, caching, transactions and optional method level security. Molecule Database Framework supports multi-component chemical compounds (mixtures). Furthermore the design of entity classes and the reasoning behind it are explained. By means of a simple web application I describe how the framework could be used. I then benchmarked this example application to create some basic performance expectations for chemical structure searches and import and export of SD-files. Conclusions By using a simple web application it was shown that Molecule Database Framework successfully abstracts chemical structure searches and SD-File import and export to simple method calls. The framework offers good search performance on a standard laptop without any database tuning. This is also due to the fact that chemical structure searches are paged and cached. Molecule Database Framework is available for download on the projects web page on bitbucket: https://bitbucket.org/kienerj/moleculedatabaseframework. PMID:24325762

Molecule database framework: a framework for creating database applications with chemical structure search capability.

PubMed

Kiener, Joos

2013-12-11

Research in organic chemistry generates samples of novel chemicals together with their properties and other related data. The involved scientists must be able to store this data and search it by chemical structure. There are commercial solutions for common needs like chemical registration systems or electronic lab notebooks. However for specific requirements of in-house databases and processes no such solutions exist. Another issue is that commercial solutions have the risk of vendor lock-in and may require an expensive license of a proprietary relational database management system. To speed up and simplify the development for applications that require chemical structure search capabilities, I have developed Molecule Database Framework. The framework abstracts the storing and searching of chemical structures into method calls. Therefore software developers do not require extensive knowledge about chemistry and the underlying database cartridge. This decreases application development time. Molecule Database Framework is written in Java and I created it by integrating existing free and open-source tools and frameworks. The core functionality includes:•Support for multi-component compounds (mixtures)•Import and export of SD-files•Optional security (authorization)For chemical structure searching Molecule Database Framework leverages the capabilities of the Bingo Cartridge for PostgreSQL and provides type-safe searching, caching, transactions and optional method level security. Molecule Database Framework supports multi-component chemical compounds (mixtures).Furthermore the design of entity classes and the reasoning behind it are explained. By means of a simple web application I describe how the framework could be used. I then benchmarked this example application to create some basic performance expectations for chemical structure searches and import and export of SD-files. By using a simple web application it was shown that Molecule Database Framework successfully abstracts chemical structure searches and SD-File import and export to simple method calls. The framework offers good search performance on a standard laptop without any database tuning. This is also due to the fact that chemical structure searches are paged and cached. Molecule Database Framework is available for download on the projects web page on bitbucket: https://bitbucket.org/kienerj/moleculedatabaseframework.

Is quantum theory a form of statistical mechanics?

NASA Astrophysics Data System (ADS)

Adler, S. L.

2007-05-01

We give a review of the basic themes of my recent book: Adler S L 2004 Quantum Theory as an Emergent Phenomenon (Cambridge: Cambridge University Press). We first give motivations for considering the possibility that quantum mechanics is not exact, but is instead an accurate asymptotic approximation to a deeper level theory. For this deeper level, we propose a non-commutative generalization of classical mechanics, that we call "trace dynamics", and we give a brief survey of how it works, considering for simplicity only the bosonic case. We then discuss the statistical mechanics of trace dynamics and give our argument that with suitable approximations, the Ward identities for trace dynamics imply that ensemble averages in the canonical ensemble correspond to Wightman functions in quantum field theory. Thus, quantum theory emerges as the statistical thermodynamics of trace dynamics. Finally, we argue that Brownian motion corrections to this thermodynamics lead to stochastic corrections to the Schrödinger equation, of the type that have been much studied in the "continuous spontaneous localization" model of objective state vector reduction. In appendices to the talk, we give details of the existence of a conserved operator in trace dynamics that encodes the structure of the canonical algebra, of the derivation of the Ward identities, and of the proof that the stochastically-modified Schrödinger equation leads to state vector reduction with Born rule probabilities.

Applicability of the Calgary-Cambridge Guide to Dog and Cat Owners for Teaching Veterinary Clinical Communications.

PubMed

Englar, Ryane E; Williams, Melanie; Weingand, Kurt

2016-01-01

Effective communication in health care benefits patients. Medical and veterinary schools not only have a responsibility to teach communication skills, the American Veterinary Medical Association (AVMA) Council on Education (COE) requires that communication be taught in all accredited colleges of veterinary medicine. However, the best strategy for designing a communications curriculum is unclear. The Calgary-Cambridge Guide (CCG) is one of many models developed in human medicine as an evidence-based approach to structuring the clinical consultation through 71 communication skills. The model has been revised by Radford et al. (2006) for use in veterinary curricula; however, the best approach for veterinary educators to teach communication remains to be determined. This qualitative study investigated if one adaptation of the CCG currently taught at Midwestern University College of Veterinary Medicine (MWU CVM) fulfills client expectations of what constitutes clinically effective communication. Two focus groups (cat owners and dog owners) were conducted with a total of 13 participants to identify common themes in veterinary communication. Participants compared communication skills they valued to those taught by MWU CVM. The results indicated that while the CCG skills that MWU CVM adopted are applicable to cat and dog owners, they are not comprehensive. Participants expressed the need to expand the skillset to include compassionate transparency and unconditional positive regard. Participants also expressed different communication needs that were attributed to the species of companion animal owned.

Assessing public aesthetic preferences towards some urban landscape patterns: the case study of two different geographic groups.

PubMed

Chen, Ziyue; Xu, Bing; Devereux, Bernard

2016-01-01

Landscape aesthetics is closely linked to people's daily life, and a large body of studies has been conducted to understand the public's landscape preferences. These studies commonly focused on comprehensive landscape configuration, yet limited emphasis was placed on the patterns of individual landscape features. This research explored people's preferences towards the composition and patterns of some specific urban features. Questionnaire-based survey was conducted in two cities: Cambridge, UK and Nanjing, China and more than 180 responses were collected, respectively. Respondents from both sites showed similar preferences towards freely growing trees, individual houses, gable roofs and mixed design of green spaces. On the other hand, respondents from Cambridge and Nanjing have different preferences towards the height of trees, the size of green spaces, and the height diversity of buildings. This survey also proved that the factors of age, education, status and length of living have larger influences on landscape preferences than the factors of gender, and major. Furthermore, strong correlations were found between people's aesthetic preferences towards comparative landscape patterns, building types, tree shapes and roof structures. The existence of generally shared landscape preferences makes it feasible to conduct international and standardized projects for acquiring comparable and transferable criteria. The methodology and findings of this research provides landscape planners and decision makers with useful reference to compare, evaluate and improve urban landscape configurations to meet people's needs.

Which preparatory curriculum for the International Baccalaureate Diploma Programme is best? The challenge for international schools with regard to mathematics and science

NASA Astrophysics Data System (ADS)

Corlu, M. Sencer

2014-12-01

There are two mainstream curricula for international school students at the junior high level: the International Baccalaureate (IB) Middle Years Programme (MYP) and the Cambridge International General Certificate of Secondary Education (IGCSE). The former was developed in the mid-1990s and is currently being relaunched in a 21st-century approach. The latter programme of study was developed by University of Cambridge International Examinations in 1985 and has become popular in recent years among British domestic and international schools worldwide due to the clarity of its learning content. The prevailing uncertainty about which curriculum is best to prepare students for the IB Diploma Programme represents a challenge for international schools. The purpose of the current study is to develop a methodology through causal models which can explain the relationship between student performance in the IGCSE and the Diploma Programme with regard to mathematics and science. The data evaluated here consisted of external examination scores of students who attended a private international high school between the years 2005 and 2012. Two structural equation models were developed. The first model employed a maximum likelihood estimation, while the second model used a Bayesian estimation with a Markov Chain Monte Carlo method. Both models fit the data well. The evidence suggests that the IGCSE provides a good foundational preparation for the Diploma Programme in mathematics and science.

The making of the architecture of the plant cell wall: how cells exploit geometry.

PubMed

Emons, A M; Mulder, B M

1998-06-09

Cell wall deposition is a key process in the formation, growth, and differentiation of plant cells. The most important structural components of the wall are long cellulose microfibrils, which are synthesized by synthases embedded in the plasma membrane. A fundamental question is how the microfibrils become oriented during deposition at the plasma membrane. The current textbook explanation for the orientation mechanism is a guidance system mediated by cortical microtubules. However, too many contraindications are known in secondary cell walls for this to be a universal mechanism, particularly in the case of helicoidal arrangements, which occur in many situations. An additional construction mechanism involves liquid crystalline self-assembly [A. C. Neville (1993) Biology of Fibrous Composites: Development Beyond the Cell Membrane (Cambridge Univ. Press, Cambridge, U.K.)], but the required amount of bulk material that is able to equilibrate thermally is not normally present at any stage of the wall deposition process. Therefore, we have asked whether the complex ordered texture of helicoidal cell walls can be formed in the absence of direct cellular guidance mechanisms. We propose that they can be formed by a mechanism that is based on geometrical considerations. It explains the genesis of the complicated helicoidal texture and shows that the cell has intrinsic, versatile tools for creating a variety of textures. A compelling feature of the model is that local rules generate global order, a typical phenomenon of life.

Fractality and the law of the wall

NASA Astrophysics Data System (ADS)

Xu, Haosen H. A.; Yang, X. I. A.

2018-05-01

Fluid motions in the inertial range of isotropic turbulence are fractal, with their space-filling capacity slightly below regular three-dimensional objects, which is a consequence of the energy cascade. Besides the energy cascade, the other often encountered cascading process is the momentum cascade in wall-bounded flows. Despite the long-existing analogy between the two processes, many of the thoroughly investigated aspects of the energy cascade have so far received little attention in studies of the momentum counterpart, e.g., the possibility of the momentum-transferring scales in the logarithmic region being fractal has not been considered. In this work, this possibility is pursued, and we discuss one of its implications. Following the same dimensional arguments that lead to the D =2.33 fractal dimension of wrinkled surfaces in isotropic turbulence, we show that the large-scale momentum-carrying eddies may also be fractal and non-space-filling, which then leads to the power-law scaling of the mean velocity profile. The logarithmic law of the wall, on the other hand, corresponds to space-filling eddies, as suggested by Townsend [The Structure of Turbulent Shear Flow (Cambridge University Press, Cambridge, 1980)]. Because the space-filling capacity is an integral geometric quantity, the analysis presented in this work provides us with a low-order quantity, with which, one would be able to distinguish between the logarithmic law and the power law.

An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system

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

AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide

Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database inmore » which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.« less

An affinity-structure database of helix-turn-helix: DNA complexes with a universal coordinate system

DOE PAGES

AlQuraishi, Mohammed; Tang, Shengdong; Xia, Xide

2015-11-19

Molecular interactions between proteins and DNA molecules underlie many cellular processes, including transcriptional regulation, chromosome replication, and nucleosome positioning. Computational analyses of protein-DNA interactions rely on experimental data characterizing known protein-DNA interactions structurally and biochemically. While many databases exist that contain either structural or biochemical data, few integrate these two data sources in a unified fashion. Such integration is becoming increasingly critical with the rapid growth of structural and biochemical data, and the emergence of algorithms that rely on the synthesis of multiple data types to derive computational models of molecular interactions. We have developed an integrated affinity-structure database inmore » which the experimental and quantitative DNA binding affinities of helix-turn-helix proteins are mapped onto the crystal structures of the corresponding protein-DNA complexes. This database provides access to: (i) protein-DNA structures, (ii) quantitative summaries of protein-DNA binding affinities using position weight matrices, and (iii) raw experimental data of protein-DNA binding instances. Critically, this database establishes a correspondence between experimental structural data and quantitative binding affinity data at the single basepair level. Furthermore, we present a novel alignment algorithm that structurally aligns the protein-DNA complexes in the database and creates a unified residue-level coordinate system for comparing the physico-chemical environments at the interface between complexes. Using this unified coordinate system, we compute the statistics of atomic interactions at the protein-DNA interface of helix-turn-helix proteins. We provide an interactive website for visualization, querying, and analyzing this database, and a downloadable version to facilitate programmatic analysis. Lastly, this database will facilitate the analysis of protein-DNA interactions and the development of programmatic computational methods that capitalize on integration of structural and biochemical datasets. The database can be accessed at http://ProteinDNA.hms.harvard.edu.« less

Purine 3':5'-cyclic nucleotides with the nucleobase in a syn orientation: cAMP, cGMP and cIMP.

PubMed

Řlepokura, Katarzyna Anna

2016-06-01

Purine 3':5'-cyclic nucleotides are very well known for their role as the secondary messengers in hormone action and cellular signal transduction. Nonetheless, their solid-state conformational details still require investigation. Five crystals containing purine 3':5'-cyclic nucleotides have been obtained and structurally characterized, namely adenosine 3':5'-cyclic phosphate dihydrate, C10H12N5O6P·2H2O or cAMP·2H2O, (I), adenosine 3':5'-cyclic phosphate 0.3-hydrate, C10H12N5O6P·0.3H2O or cAMP·0.3H2O, (II), guanosine 3':5'-cyclic phosphate pentahydrate, C10H12N5O7P·5H2O or cGMP·5H2O, (III), sodium guanosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H11N5O7P(-)·4H2O or Na(cGMP)·4H2O, (IV), and sodium inosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H10N4O7P(-)·4H2O or Na(cIMP)·4H2O, (V). Most of the cyclic nucleotide zwitterions/anions [two from four cAMP present in total in (I) and (II), cGMP in (III), cGMP(-) in (IV) and cIMP(-) in (V)] are syn conformers about the N-glycosidic bond, and this nucleobase arrangement is accompanied by Crib-H...Npur hydrogen bonds (rib = ribose and pur = purine). The base orientation is tuned by the ribose pucker. An analysis of data obtained from the Cambridge Structural Database made in the context of syn-anti conformational preferences has revealed that among the syn conformers of various purine nucleotides, cyclic nucleotides and dinucleotides predominate significantly. The interactions stabilizing the syn conformation have been indicated. The inter-nucleotide contacts in (I)-(V) have been systematized in terms of the chemical groups involved. All five structures display three-dimensional hydrogen-bonded networks.

The Cambridge Car Memory Test: a task matched in format to the Cambridge Face Memory Test, with norms, reliability, sex differences, dissociations from face memory, and expertise effects.

PubMed

Dennett, Hugh W; McKone, Elinor; Tavashmi, Raka; Hall, Ashleigh; Pidcock, Madeleine; Edwards, Mark; Duchaine, Bradley

2012-06-01

Many research questions require a within-class object recognition task matched for general cognitive requirements with a face recognition task. If the object task also has high internal reliability, it can improve accuracy and power in group analyses (e.g., mean inversion effects for faces vs. objects), individual-difference studies (e.g., correlations between certain perceptual abilities and face/object recognition), and case studies in neuropsychology (e.g., whether a prosopagnosic shows a face-specific or object-general deficit). Here, we present such a task. Our Cambridge Car Memory Test (CCMT) was matched in format to the established Cambridge Face Memory Test, requiring recognition of exemplars across view and lighting change. We tested 153 young adults (93 female). Results showed high reliability (Cronbach's alpha = .84) and a range of scores suitable both for normal-range individual-difference studies and, potentially, for diagnosis of impairment. The mean for males was much higher than the mean for females. We demonstrate independence between face memory and car memory (dissociation based on sex, plus a modest correlation between the two), including where participants have high relative expertise with cars. We also show that expertise with real car makes and models of the era used in the test significantly predicts CCMT performance. Surprisingly, however, regression analyses imply that there is an effect of sex per se on the CCMT that is not attributable to a stereotypical male advantage in car expertise.

NewsMars: Express journey to Mars ASE 2003: Knocked out by meteorites Events: Sun-Earth Day ASE 2003: Fun Physics - popular as ever Appointments: Sykes to bring science to the people UK Science Education: The future's bright, the future's science ASE 2003: A grand finale for Catherine Teaching Resources: UK goes to the planets Cambridge Physics Update: Basement physics Conferences: Earth Science Teachers' Association Conference 2003 New Website: JESEI sets sail GIREP: Teacher education seminar Malaysia: Rewards for curriculum change Cambridge Physics Update: My boomerang will come back! Teaching Resources: Widening particiption through ideas and evidence with the University of Surrey Wales: First Ffiseg Events: Nuna: Solar car on tour Physics on Stage: Physics on Stage 3 embraces life Symposium: In what sense a nuclear 'debate'? Gifted and Talented: Able pupils experiencing challenging science Australia: ISS flies high Down Under

NASA Astrophysics Data System (ADS)

2003-03-01

Mars: Express journey to Mars ASE 2003: Knocked out by meteorites Events: Sun-Earth Day ASE 2003: Fun Physics - popular as ever Appointments: Sykes to bring science to the people UK Science Education: The future's bright, the future's science ASE 2003: A grand finale for Catherine Teaching Resources: UK goes to the planets Cambridge Physics Update: Basement physics Conferences: Earth Science Teachers' Association Conference 2003 New Website: JESEI sets sail GIREP: Teacher education seminar Malaysia: Rewards for curriculum change Cambridge Physics Update: My boomerang will come back! Teaching Resources: Widening particiption through ideas and evidence with the University of Surrey Wales: First Ffiseg Events: Nuna: Solar car on tour Physics on Stage: Physics on Stage 3 embraces life Symposium: In what sense a nuclear 'debate'? Gifted and Talented: Able pupils experiencing challenging science Australia: ISS flies high Down Under

A Head Start to a Healthy Heart

NASA Technical Reports Server (NTRS)

2002-01-01

Cambridge Heart, Inc., has licensed the only U.S. Food and Drug Administration-cleared tool to identify those at risk for sudden cardiac death (SCD). The Microvolt T-Wave Alternans Test(TM) was invented by Dr. Richard J. Cohen, a professor at the Harvard-Massachusetts Institute of Technology (MIT) Division of Health Sciences and Technology, with developmental support and funding from NASA's Johnson Space Center and the National Space Biomedical Research Institute (NSBRI) in Houston, Texas. In 1993, MIT licensed the technology to Cambridge Heart, Inc., a start-up company that Dr. Cohen helped to establish. Cambridge Heart's non-invasive technology measures T-wave alternans, a change from one heartbeat to the next that is too minute to be detected by a standard electrocardiogram. Cardiac patients with such a change in heartbeat regulation are faced with a much greater risk of ventricular arrhythmia and SCD than those without it. The company's ability to measure electrical alternans on a microvolt level has been clinically proven to be just as accurate as - and in some studies, more accurate than - more costly and somewhat risky, invasive procedures, such as electrophysiological testing.

The Monthly Sky Guide: Sixth Edition

NASA Astrophysics Data System (ADS)

Ridpath, Ian; Tirion, Wil

2003-06-01

The latest edition of Ian Ridpath and Wil Tirion's popular guide to the night sky is updated for planet positions and forthcoming eclipses up to the end of the year 2007. With one chapter for each month of the year, this is an easy-to-use handbook for anyone wanting to identify constellations, star clusters, nebulae, to plot the movement of planets, or witness solar and lunar eclipses. Most of the features discussed are visible to the naked eye and all can be seen with a small telescope or binoculars. Ian Ridpath has been a full-time writer, broadcaster and lecturer on astronomy and space for more than twenty-five years. He has written and edited more than 40 books, including A Comet Called Haley (Cambridge, 1985). Wil Tirion made his first star map in 1977. It showed stars to the magnitude of 6.5 and was issued as a set of maps by the British Astronomical Association in 1981. He has illustrated numerous books and magazines, including The Cambridge Star Atlas (Cambridge, 2001). Previous Edition Pb (1999): 0-521-66771-2

Trials and tribulations of playing the devil's advocate

NASA Astrophysics Data System (ADS)

Narlikar, Jayant V.

2015-01-01

Beginning with his student days at school and college, the author describes his training at Cambridge with special emphasis on his mentor Fred Hoyle. His early experience of participating in a controversy at Cambridge played a major role in giving him the confidence to defend his scientific ideas. All through his later life he chose areas that were not part of mainstream research. These included the steady state theory and later the quasi steady state cosmology, action at a distance, noncosmological redshifts, quantum conformal cosmology, etc. After being a founding member of the Institute of Theoretical Astronomy (IOTA) at Cambridge, the author joined the Tata Institute of Fundamental Research (TIFR) in Mumbai and later moved to Pune to set up the Inter-University Centre for Astronomy and Astrophysics (IUCAA). He briefly reviews his own work and ends by pointing out the difficulties a non-conformist scientist faces in his professional life. In the conclusion, he mentions his interests in science popularization and science fiction for which he has won awards and appreciation, including UNESCO's Kalinga Prize.

Revisiting the blind tests in crystal structure prediction: accurate energy ranking of molecular crystals.

PubMed

Asmadi, Aldi; Neumann, Marcus A; Kendrick, John; Girard, Pascale; Perrin, Marc-Antoine; Leusen, Frank J J

2009-12-24

In the 2007 blind test of crystal structure prediction hosted by the Cambridge Crystallographic Data Centre (CCDC), a hybrid DFT/MM method correctly ranked each of the four experimental structures as having the lowest lattice energy of all the crystal structures predicted for each molecule. The work presented here further validates this hybrid method by optimizing the crystal structures (experimental and submitted) of the first three CCDC blind tests held in 1999, 2001, and 2004. Except for the crystal structures of compound IX, all structures were reminimized and ranked according to their lattice energies. The hybrid method computes the lattice energy of a crystal structure as the sum of the DFT total energy and a van der Waals (dispersion) energy correction. Considering all four blind tests, the crystal structure with the lowest lattice energy corresponds to the experimentally observed structure for 12 out of 14 molecules. Moreover, good geometrical agreement is observed between the structures determined by the hybrid method and those measured experimentally. In comparison with the correct submissions made by the blind test participants, all hybrid optimized crystal structures (apart from compound II) have the smallest calculated root mean squared deviations from the experimentally observed structures. It is predicted that a new polymorph of compound V exists under pressure.

A dynamic clinical dental relational database.

PubMed

Taylor, D; Naguib, R N G; Boulton, S

2004-09-01

The traditional approach to relational database design is based on the logical organization of data into a number of related normalized tables. One assumption is that the nature and structure of the data is known at the design stage. In the case of designing a relational database to store historical dental epidemiological data from individual clinical surveys, the structure of the data is not known until the data is presented for inclusion into the database. This paper addresses the issues concerned with the theoretical design of a clinical dynamic database capable of adapting the internal table structure to accommodate clinical survey data, and presents a prototype database application capable of processing, displaying, and querying the dental data.

TRANSFORMATION OF DEVELOPMENTAL NEUROTOXICITY DATA INTO STRUCTURE-SEARCHABLE TOXML DATABASE IN SUPPORT OF STRUCTURE-ACTIVITY RELATIONSHIP (SAR) WORKFLOW.

EPA Science Inventory

Early hazard identification of new chemicals is often difficult due to lack of data on the novel material for toxicity endpoints, including neurotoxicity. At present, there are no structure searchable neurotoxicity databases. A working group was formed to construct a database to...

Databases and Associated Tools for Glycomics and Glycoproteomics.

PubMed

Lisacek, Frederique; Mariethoz, Julien; Alocci, Davide; Rudd, Pauline M; Abrahams, Jodie L; Campbell, Matthew P; Packer, Nicolle H; Ståhle, Jonas; Widmalm, Göran; Mullen, Elaine; Adamczyk, Barbara; Rojas-Macias, Miguel A; Jin, Chunsheng; Karlsson, Niclas G

2017-01-01

The access to biodatabases for glycomics and glycoproteomics has proven to be essential for current glycobiological research. This chapter presents available databases that are devoted to different aspects of glycobioinformatics. This includes oligosaccharide sequence databases, experimental databases, 3D structure databases (of both glycans and glycorelated proteins) and association of glycans with tissue, disease, and proteins. Specific search protocols are also provided using tools associated with experimental databases for converting primary glycoanalytical data to glycan structural information. In particular, researchers using glycoanalysis methods by U/HPLC (GlycoBase), MS (GlycoWorkbench, UniCarb-DB, GlycoDigest), and NMR (CASPER) will benefit from this chapter. In addition we also include information on how to utilize glycan structural information to query databases that associate glycans with proteins (UniCarbKB) and with interactions with pathogens (SugarBind).

IECON '87: Industrial applications of control and simulation; Proceedings of the 1987 International Conference on Industrial Electronics, Control, and Instrumentation, Cambridge, MA, Nov. 3, 4, 1987

NASA Technical Reports Server (NTRS)

Hartley, Tom T. (Editor)

1987-01-01

Recent advances in control-system design and simulation are discussed in reviews and reports. Among the topics considered are fast algorithms for generating near-optimal binary decision programs, trajectory control of robot manipulators with compensation of load effects via a six-axis force sensor, matrix integrators for real-time simulation, a high-level control language for an autonomous land vehicle, and a practical engineering design method for stable model-reference adaptive systems. Also addressed are the identification and control of flexible-limb robots with unknown loads, adaptive control and robust adaptive control for manipulators with feedforward compensation, adaptive pole-placement controllers with predictive action, variable-structure strategies for motion control, and digital signal-processor-based variable-structure controls.

First Images From Chandra X-Ray Observatory to be Released

NASA Astrophysics Data System (ADS)

1999-08-01

The first images from the world's most powerful X-ray telescope, NASA's Chandra X-ray Observatory, will be unveiled at a media briefing at 1 p.m. EDT, Thursday, Aug. 26. The briefing will be held in the James E. Webb Auditorium at NASA Headquarters, 300 E St. SW, Washington, DC. The images include the spectacular remnants of a supernova and other astronomical objects. Panelists will be: - Dr. Edward Weiler, Associate Administrator for Space Science, NASA Headquarters, Washington, DC; - Dr. Harvey Tananbaum, Director of the Smithsonian Astrophysical Observatory's Chandra X-ray Center, Cambridge, MA; - Dr. Martin Weisskopf, NASA's Chandra Project Scientist, NASA's Marshall Space Flight Center, Huntsville, AL; and - Dr. Robert Kirshner, astrophysicist, Harvard University, Cambridge, MA. The event will be carried live on NASA Television with question-and-answer capability for reporters covering the briefing from participating NASA centers and from the Chandra Operations Control Center in Cambridge. NASA Television is available on transponder 9C, satellite GE-2 at 85 degrees West longitude, vertical polarization, frequency 3880 MHz, audio of 6.8 MHz. Chandra has been undergoing activation and checkout since it was placed into orbit during Space Shuttle mission STS-93 in July. Chandra will examine exploding stars, black holes, colliding galaxies and other high-energy cosmic phenomena to help scientists gain a better understanding of the structure and evolution of the universe. Chandra images and additional information will be available following the briefing on the Internet at: http://chandra.nasa.gov and http://chandra.harvard.edu NASA press releases and other information are available automatically by sending an Internet electronic mail message to domo@hq.nasa.gov. In the body of the message (not the subject line) users should type the words "subscribe press-release" (no quotes). The system will reply with a confirmation via E-mail of each subscription. A second automatic message will include additional information on the service. NASA releases also are available via CompuServe using the command GO NASA. To unsubscribe from this mailing list, address an E-mail message to domo@hq.nasa.gov, leave the subject blank, and type only "unsubscribe press-release" (no quotes) in the body of the message.

CREDO: a structural interactomics database for drug discovery

PubMed Central

Schreyer, Adrian M.; Blundell, Tom L.

2013-01-01

CREDO is a unique relational database storing all pairwise atomic interactions of inter- as well as intra-molecular contacts between small molecules and macromolecules found in experimentally determined structures from the Protein Data Bank. These interactions are integrated with further chemical and biological data. The database implements useful data structures and algorithms such as cheminformatics routines to create a comprehensive analysis platform for drug discovery. The database can be accessed through a web-based interface, downloads of data sets and web services at http://www-cryst.bioc.cam.ac.uk/credo. Database URL: http://www-cryst.bioc.cam.ac.uk/credo PMID:23868908

E-MSD: an integrated data resource for bioinformatics

PubMed Central

Velankar, S.; McNeil, P.; Mittard-Runte, V.; Suarez, A.; Barrell, D.; Apweiler, R.; Henrick, K.

2005-01-01

The Macromolecular Structure Database (MSD) group (http://www.ebi.ac.uk/msd/) continues to enhance the quality and consistency of macromolecular structure data in the worldwide Protein Data Bank (wwPDB) and to work towards the integration of various bioinformatics data resources. One of the major obstacles to the improved integration of structural databases such as MSD and sequence databases like UniProt is the absence of up to date and well-maintained mapping between corresponding entries. We have worked closely with the UniProt group at the EBI to clean up the taxonomy and sequence cross-reference information in the MSD and UniProt databases. This information is vital for the reliable integration of the sequence family databases such as Pfam and Interpro with the structure-oriented databases of SCOP and CATH. This information has been made available to the eFamily group (http://www.efamily.org.uk/) and now forms the basis of the regular interchange of information between the member databases (MSD, UniProt, Pfam, Interpro, SCOP and CATH). This exchange of annotation information has enriched the structural information in the MSD database with annotation from wider sequence-oriented resources. This work was carried out under the ‘Structure Integration with Function, Taxonomy and Sequences (SIFTS)’ initiative (http://www.ebi.ac.uk/msd-srv/docs/sifts) in the MSD group. PMID:15608192

SM-TF: A structural database of small molecule-transcription factor complexes.

PubMed

Xu, Xianjin; Ma, Zhiwei; Sun, Hongmin; Zou, Xiaoqin

2016-06-30

Transcription factors (TFs) are the proteins involved in the transcription process, ensuring the correct expression of specific genes. Numerous diseases arise from the dysfunction of specific TFs. In fact, over 30 TFs have been identified as therapeutic targets of about 9% of the approved drugs. In this study, we created a structural database of small molecule-transcription factor (SM-TF) complexes, available online at http://zoulab.dalton.missouri.edu/SM-TF. The 3D structures of the co-bound small molecule and the corresponding binding sites on TFs are provided in the database, serving as a valuable resource to assist structure-based drug design related to TFs. Currently, the SM-TF database contains 934 entries covering 176 TFs from a variety of species. The database is further classified into several subsets by species and organisms. The entries in the SM-TF database are linked to the UniProt database and other sequence-based TF databases. Furthermore, the druggable TFs from human and the corresponding approved drugs are linked to the DrugBank. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Evidence for a strong sulfur-aromatic interaction derived from crystallographic data.

PubMed

Zauhar, R J; Colbert, C L; Morgan, R S; Welsh, W J

2000-03-01

We have uncovered new evidence for a significant interaction between divalent sulfur atoms and aromatic rings. Our study involves a statistical analysis of interatomic distances and other geometric descriptors derived from entries in the Cambridge Crystallographic Database (F. H. Allen and O. Kennard, Chem. Design Auto. News, 1993, Vol. 8, pp. 1 and 31-37). A set of descriptors was defined sufficient in number and type so as to elucidate completely the preferred geometry of interaction between six-membered aromatic carbon rings and divalent sulfurs for all crystal structures of nonmetal-bearing organic compounds present in the database. In order to test statistical significance, analogous probability distributions for the interaction of the moiety X-CH(2)-X with aromatic rings were computed, and taken a priori to correspond to the null hypothesis of no significant interaction. Tests of significance were carried our pairwise between probability distributions of sulfur-aromatic interaction descriptors and their CH(2)-aromatic analogues using the Smirnov-Kolmogorov nonparametric test (W. W. Daniel, Applied Nonparametric Statistics, Houghton-Mifflin: Boston, New York, 1978, pp. 276-286), and in all cases significance at the 99% confidence level or better was observed. Local maxima of the probability distributions were used to define a preferred geometry of interaction between the divalent sulfur moiety and the aromatic ring. Molecular mechanics studies were performed in an effort to better understand the physical basis of the interaction. This study confirms observations based on statistics of interaction of amino acids in protein crystal structures (R. S. Morgan, C. E. Tatsch, R. H. Gushard, J. M. McAdon, and P. K. Warme, International Journal of Peptide Protein Research, 1978, Vol. 11, pp. 209-217; R. S. Morgan and J. M. McAdon, International Journal of Peptide Protein Research, 1980, Vol. 15, pp. 177-180; K. S. C. Reid, P. F. Lindley, and J. M. Thornton, FEBS Letters, 1985, Vol. 190, pp. 209-213), as well as studies involving molecular mechanics (G. Nemethy and H. A. Scheraga, Biochemistry and Biophysics Research Communications, 1981, Vol. 98, pp. 482-487) and quantum chemical calculations (B. V. Cheney, M. W. Schulz, and J. Cheney, Biochimica Biophysica Acta, 1989, Vol. 996, pp.116-124; J. Pranata, Bioorganic Chemistry, 1997, Vol. 25, pp. 213-219)-all of which point to the possible importance of the sulfur-aromatic interaction. However, the preferred geometry of the interaction, as determined from our analysis of the small-molecule crystal data, differs significantly from that found by other approaches. Copyright 2000 John Wiley & Sons, Inc.

StraPep: a structure database of bioactive peptides

PubMed Central

Wang, Jian; Yin, Tailang; Xiao, Xuwen; He, Dan; Xue, Zhidong; Jiang, Xinnong; Wang, Yan

2018-01-01

Abstract Bioactive peptides, with a variety of biological activities and wide distribution in nature, have attracted great research interest in biological and medical fields, especially in pharmaceutical industry. The structural information of bioactive peptide is important for the development of peptide-based drugs. Many databases have been developed cataloguing bioactive peptides. However, to our knowledge, database dedicated to collect all the bioactive peptides with known structure is not available yet. Thus, we developed StraPep, a structure database of bioactive peptides. StraPep holds 3791 bioactive peptide structures, which belong to 1312 unique bioactive peptide sequences. About 905 out of 1312 (68%) bioactive peptides in StraPep contain disulfide bonds, which is significantly higher than that (21%) of PDB. Interestingly, 150 out of 616 (24%) bioactive peptides with three or more disulfide bonds form a structural motif known as cystine knot, which confers considerable structural stability on proteins and is an attractive scaffold for drug design. Detailed information of each peptide, including the experimental structure, the location of disulfide bonds, secondary structure, classification, post-translational modification and so on, has been provided. A wide range of user-friendly tools, such as browsing, sequence and structure-based searching and so on, has been incorporated into StraPep. We hope that this database will be helpful for the research community. Database URL: http://isyslab.info/StraPep PMID:29688386

PROFESS: a PROtein Function, Evolution, Structure and Sequence database

PubMed Central

Triplet, Thomas; Shortridge, Matthew D.; Griep, Mark A.; Stark, Jaime L.; Powers, Robert; Revesz, Peter

2010-01-01

The proliferation of biological databases and the easy access enabled by the Internet is having a beneficial impact on biological sciences and transforming the way research is conducted. There are ∼1100 molecular biology databases dispersed throughout the Internet. To assist in the functional, structural and evolutionary analysis of the abundant number of novel proteins continually identified from whole-genome sequencing, we introduce the PROFESS (PROtein Function, Evolution, Structure and Sequence) database. Our database is designed to be versatile and expandable and will not confine analysis to a pre-existing set of data relationships. A fundamental component of this approach is the development of an intuitive query system that incorporates a variety of similarity functions capable of generating data relationships not conceived during the creation of the database. The utility of PROFESS is demonstrated by the analysis of the structural drift of homologous proteins and the identification of potential pancreatic cancer therapeutic targets based on the observation of protein–protein interaction networks. Database URL: http://cse.unl.edu/∼profess/ PMID:20624718

British Pharmacological Society Cambridge Symposia. 5-7 January 2000, Cambridge, UK.

PubMed

Lawson, K

2000-04-01

This meeting covered a broad range of pharmacological topics, although the main themes were covered in four mini-symposia. This report concentrates on the cannabinoid, pain and cardiac ischemia symposia. The cannabinoid system was identified as a major area of potential therapeutic interest, offering a number of clinical targets that may be modified through the actions of selective ligands. Novel approaches to the treatment of neurogenic pain, where conventional analgesics have limited value, are being explored with significant success. The role of delayed preconditioning in cardiac ischemia was also addressed as a mechanism of cardioprotection.

Brief history of the Cambridge STEM aberration correction project and its progeny.

PubMed

Brown, L Michael; Batson, Philip E; Dellby, Niklas; Krivanek, Ondrej L

2015-10-01

We provide a brief history of the project to correct the spherical aberration of the scanning transmission electron microscope (STEM) that started in Cambridge (UK) and continued in Kirkland (WA, USA), Yorktown Heights (NY, USA), and other places. We describe the project in the full context of other aberration correction research and related work, partly in response to the incomplete context presented in the paper "In quest of perfection in electron optics: A biographical sketch of Harald Rose on the occasion of his 80th birthday", recently published in Ultramicroscopy. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of Identify-Friend-Foe and Blue-Force Tracking Decision Support for Combat Identification (Comparaison des Systemes d’aide a la Decision Identification ami ou Ennemi et Suivi des Forces Bleues pour l’Identification au Combat)

DTIC Science & Technology

2011-02-01

In the context of the CID task, sensitivity refers to subjects’ psychological discrimination between friends and foes, or their ability to...G. A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97...Wiley. 21. Macmillan, N. A., & Creelman , C. D. (1991). Detection theory: A user’s guide. Cambridge, UK: Cambridge University Press. DRDC Toronto

VizieR Online Data Catalog: Radial velocities of 1 Gem (Lane+, 2014)

NASA Astrophysics Data System (ADS)

Lane, B. F.; Muterspaugh, M. W.; Griffin, R. F.; Scarfe, C. D.; Fekel, F. C.; Williamson, M. H.; Eaton, J. A.; Shao, M.; Colavita, M. M.; Konacki, M.

2016-05-01

Extensive radial-velocity measurements of the 1 Gem system have been obtained in four separate campaigns spanning 40yr, including data from eight different instruments. Between 1969 and 2009 R.F.G. acquired a total of 128 observations of 1 Gem using the original radial-velocity spectrometer at Cambridge; a second-generation, computerized instrument at Palomar; the CORAVEL spectrometer at Haute Provence Observatory (OHP), and most recently, the Cambridge CORAVEL. The "Cambridge CORAVEL" operates at the Coude focus of the 36inch reflector on the home site of the Cambridge Observatories, Madingley Road, Cambridge, England. The Cambridge and Palomar data are referred to as data set A, while the OHP data are labeled set B. The data for components A and Ba are provided in Table1. A series of observations of 1 Gem has been obtained by C.D.S. with the Dominion Astrophysical Observatory (DAO) radial-velocity spectrometer. Observations were begun early in 1980 and continued until the end of 2003. The DAO velocities of components A and Ba are listed in Table2. The total number of acceptable velocities from DAO radial-velocity scanner observations is 123 of the primary star and 107 of the brighter component of the close pair. The third component was not detectable in the DAO traces. We identify the DAO observations as data set C. >From 1983 through 2009 F.C.F. obtained observations at the Kitt Peak National Observatory (KPNO) with the 0.9m coude feed telescope, coude spectrograph, and several different CCD detectors. All of the spectrograms were acquired with a Texas Instruments (TI) CCD except for five that were obtained in 1983 with an RCA CCD and a single observation in 2008 September with a Tektronix CCD. All those observations were centered near 6430Å and had typical signal-to-noise ratios of about 250. The numerous TI CCD spectra have a wavelength range of just 84Å and a resolution of 0.21Å. The 86 velocities of component A and 80 of component Ba are listed in Table3. They are identified as data set D. >From 2003 through 2009 J.A.E. acquired 522 spectrograms with the Tennessee State University 2m Automatic Spectroscopic Telescope (AST) situated at Fairborn Observatory near Washington Camp in the Patagonia Mountains of southeastern Arizona, fiber-fed echelle spectrograph, and a 2048*4096 SITe ST-002A CCD. The echelle spectrograms have 21 orders, covering the wavelength range 4920-7100Å with an average resolution of 0.17Å. The typical signal-to-noise ratio is ~50. The AST spectra are referred to as data set E (see Table4). (4 data files).