Detailed physico-chemical characterization of microplastics from North Atlantic Gyre

NASA Astrophysics Data System (ADS)

ter Halle, A.; Ladirat, L.; Gendre, X.; Goudouneche, D.; Pusineri, C.; Routaboul, C.; Tenailleau, C.; Duployer, B.; Perez, E.

2016-02-01

More than 260 million tonnes of plastic are used each year. Based on population density and economic status of costal countries the mass of land based plastic waste entering the ocean was recently estimated between 4.8 to 12.7 million metric tons per year1. Most striking is the estimation for 2025 that this amount will increase by an order of magnitude if waste management infrastructures are not improved. Plastic debris is abundant and widespread in the marine habitat. Marine plastic pollution has been recently recognized as a global environmental threat2. There is still a need for detailed research in terms of estimating the global scale of plastic inputs, their fate in the environment as well as the biological responses to plastic exposure in a variety of marine organisms. In this context, the present study aimed at giving a detailed physico-chemical characterization of the microplastics collected at the surface of the North Atlantic accumulation zone. A detailed description of the plastics is given in terms of size, width, density and weight together with a microscopic and infrared spectroscopy characterization. In this study, also we introduce a new fragmentation mechanism of the microplastics based on the physico-chemical data collected. This approach will be helpful for oceanographic modelling. The results will be also very useful to better understand the biological response to the plastic in terms of transfer of chemical in case of ingestion or to better understand the formation and development of the plastisphere. 1 Jambeck, J. R.; Geyer, R.; Wilcox, C.; Siegler, T. R.; Perryman, M.; Andrady, A.; Narayan, R.; Lavender Law, K., Plastic waste inputs from land into the ocean 2 Moore, C. J., Synthetic polymers in the marine environment: A rapidly increasing, long-term threat. Environmental Research 2008, 108, (2), 131-139.

Mass Spectrometry Combinations for Structural Characterization of Sulfated-Steroid Metabolites

NASA Astrophysics Data System (ADS)

Yan, Yuetian; Rempel, Don L.; Holy, Timothy E.; Gross, Michael L.

2014-05-01

Steroid conjugates, which often occur as metabolites, are challenging to characterize. One application is female-mouse urine, where steroid conjugates serve as important ligands for the pheromone-sensing neurons. Although the two with the highest abundance in mouse urine were previously characterized with mass spectrometry (MS) and NMR to be sulfated steroids, many more exist but remain structurally unresolved. Given that their physical and chemical properties are similar, they are likely to have a sulfated steroid ring structure. Because these compounds occur in trace amounts in mouse urine and elsewhere, their characterization by NMR will be difficult. Thus, MS methods become the primary approach for determining structure. Here, we show that a combination of MS tools is effective for determining the structures of sulfated steroids. Using 4-pregnene analogs, we explored high-resolving power MS (HR-MS) to determine chemical formulae; HD exchange MS (HDX-MS) to determine number of active, exchangeable hydrogens (e.g., OH groups); methoxyamine hydrochloride (MOX) derivatization MS, or reactive desorption electrospray ionization with hydroxylamine to determine the number of carbonyl groups; and tandem MS (MSn), high-resolution tandem MS (HRMS/MS), and GC-MS to obtain structural details of the steroid ring. From the fragmentation studies, we deduced three major fragmentation rules for this class of sulfated steroids. We also show that a combined MS approach is effective for determining structure of steroid metabolites, with important implications for targeted metabolomics in general and for the study of mouse social communication in particular.

Photograph of elevation and details of structure 841, used for ...

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

Photograph of elevation and details of structure 841, used for repair project, dated 1973. Drawing in collection of Caretaker Site Office, Philadelphia Naval Business Center. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Structure No. 841, Delaware Avenue between East Fourth Street & Webster Avenue, League Island, Philadelphia, Philadelphia County, PA

Multiscale Structure of UXO Site Characterization: Spatial Estimation and Uncertainty Quantification

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

Ostrouchov, George; Doll, William E.; Beard, Les P.

2009-01-01

Unexploded ordnance (UXO) site characterization must consider both how the contamination is generated and how we observe that contamination. Within the generation and observation processes, dependence structures can be exploited at multiple scales. We describe a conceptual site characterization process, the dependence structures available at several scales, and consider their statistical estimation aspects. It is evident that most of the statistical methods that are needed to address the estimation problems are known but their application-specific implementation may not be available. We demonstrate estimation at one scale and propose a representation for site contamination intensity that takes full account of uncertainty,more » is flexible enough to answer regulatory requirements, and is a practical tool for managing detailed spatial site characterization and remediation. The representation is based on point process spatial estimation methods that require modern computational resources for practical application. These methods have provisions for including prior and covariate information.« less

Structural and Dynamical Details of Biotin

NASA Astrophysics Data System (ADS)

Korter, Timothy; Dunmire, David; Romero, Danilo; Middleton, Chris; Jenkins, Tim; Hudson, Bruce; Hight Walker, Angela

2003-03-01

Biotin, one of the B vitamins, is a key cofactor of enzymes that transfer units of CO2. Chemically linked to a lysine residue via its carboxylic acid side chain, biotin exhibits incredible flexibility when performing its intraprotein transport role. Not only does Biotin play a critical role in gluconeogenesis, it also is commonly used throughout biotechnology research due to its strong binding affinity for attachment, tethering and labeling chemistries. Therefore, a detailed probe of the structure and dynamics of biotin is important both metabolically and to aid further research. Here, we used several vibrational techniques, THz, IR, Raman and Inelastic Neutron Scattering, to gain a comprehensive understanding of biotin's structure, flexibility and dynamics. Specifically our interests are in hydrogen bonding interactions, torsional vibrations, and conformational changes with varying environments, which frequently lie in the far-infrared region of the spectrum below 200 cm-1. Interpretation and comparison of our multi-technique data are guided by high-level ab initio calculations.

36. ARCHITECTURAL AND STRUCTURAL DETAILS OF ELEVATOR HOUSING, NaK HEATER ...

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

36. ARCHITECTURAL AND STRUCTURAL DETAILS OF ELEVATOR HOUSING, NaK HEATER STACK ROOF FLASHING, HOOD ELEVATION DETAIL. INCLUDES PARTIAL 'BILL OF MATERIAL.' INEEL DRAWING NUMBER 200-0633-00-287-106361. FLUOR NUMBER 5775-CPP-633-A-11. - Idaho National Engineering Laboratory, Old Waste Calcining Facility, Scoville, Butte County, ID

View northeast; interior structural detail Naval Base PhiladelphiaPhiladelphia Naval ...

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

View northeast; interior structural detail - Naval Base Philadelphia-Philadelphia Naval Shipyard, Foundry-Propeller Shop, North of Porter Avenue, west of Third Street West, Philadelphia, Philadelphia County, PA

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE.

PubMed

Pidatala, Venkataramana R; Mahboubi, Amir; Mortimer, Jenny C

2017-10-16

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharide fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.

Characterizing Sleep Structure Using the Hypnogram

PubMed Central

Swihart, Bruce J.; Caffo, Brian; Bandeen-Roche, Karen; Punjabi, Naresh M.

2008-01-01

Objectives: Research on the effects of sleep-disordered breathing (SDB) on sleep structure has traditionally been based on composite sleep-stage summaries. The primary objective of this investigation was to demonstrate the utility of log-linear and multistate analysis of the sleep hypnogram in evaluating differences in nocturnal sleep structure in subjects with and without SDB. Methods: A community-based sample of middle-aged and older adults with and without SDB matched on age, sex, race, and body mass index was identified from the Sleep Heart Health Study. Sleep was assessed with home polysomnography and categorized into rapid eye movement (REM) and non-REM (NREM) sleep. Log-linear and multistate survival analysis models were used to quantify the frequency and hazard rates of transitioning, respectively, between wakefulness, NREM sleep, and REM sleep. Results: Whereas composite sleep-stage summaries were similar between the two groups, subjects with SDB had higher frequencies and hazard rates for transitioning between the three states. Specifically, log-linear models showed that subjects with SDB had more wake-to-NREM sleep and NREM sleep-to-wake transitions, compared with subjects without SDB. Multistate survival models revealed that subjects with SDB transitioned more quickly from wake-to-NREM sleep and NREM sleep-to-wake than did subjects without SDB. Conclusions: The description of sleep continuity with log-linear and multistate analysis of the sleep hypnogram suggests that such methods can identify differences in sleep structure that are not evident with conventional sleep-stage summaries. Detailed characterization of nocturnal sleep evolution with event history methods provides additional means for testing hypotheses on how specific conditions impact sleep continuity and whether sleep disruption is associated with adverse health outcomes. Citation: Swihart BJ; Caffo B; Bandeen-Roche K; Punjabi NM. Characterizing sleep structure using the hypnogram. J Clin

Mass spectrometry combinations for structural characterization of sulfated-steroid metabolites.

PubMed

Yan, Yuetian; Rempel, Don L; Holy, Timothy E; Gross, Michael L

2014-05-01

Steroid conjugates, which often occur as metabolites, are challenging to characterize. One application is female-mouse urine, where steroid conjugates serve as important ligands for the pheromone-sensing neurons. Although the two with the highest abundance in mouse urine were previously characterized with mass spectrometry (MS) and NMR to be sulfated steroids, many more exist but remain structurally unresolved. Given that their physical and chemical properties are similar, they are likely to have a sulfated steroid ring structure. Because these compounds occur in trace amounts in mouse urine and elsewhere, their characterization by NMR will be difficult. Thus, MS methods become the primary approach for determining structure. Here, we show that a combination of MS tools is effective for determining the structures of sulfated steroids. Using 4-pregnene analogs, we explored high-resolving power MS (HR-MS) to determine chemical formulae; HD exchange MS (HDX-MS) to determine number of active, exchangeable hydrogens (e.g., OH groups); methoxyamine hydrochloride (MOX) derivatization MS, or reactive desorption electrospray ionization with hydroxylamine to determine the number of carbonyl groups; and tandem MS (MS(n)), high-resolution tandem MS (HRMS/MS), and GC-MS to obtain structural details of the steroid ring. From the fragmentation studies, we deduced three major fragmentation rules for this class of sulfated steroids. We also show that a combined MS approach is effective for determining structure of steroid metabolites, with important implications for targeted metabolomics in general and for the study of mouse social communication in particular.

Mass spectrometry combinations for structural characterization of sulfated-steroid metabolites

PubMed Central

Yan, Yuetian; Rempel, Don; Holy, Timothy E.; Gross, Michael L.

2015-01-01

Steroid conjugates, which often occur as metabolites, are challenging to characterize. One application is female-mouse urine, where steroid conjugates serve as important ligands for the pheromone-sensing neurons. Although the two with the highest abundance in mouse urine were previously characterized with mass spectrometry (MS) and NMR to be sulfated steroids, many more exist but remain structurally unresolved. Given that their physical and chemical properties are similar, they are likely to have a sulfated steroid ring structure. Because these compounds occur in trace amounts in mouse urine and elsewhere, their characterization by NMR will be difficult. Thus, MS methods become the primary approach for determining structure. Here, we show that a combination of MS tools is effective for determining the structures of sulfated steroids. Using 4-pregnene analogs, we explored high-resolving power MS (HR-MS) to determine chemical formulae; HD exchange MS (HDX-MS) to determine number of active, exchangeable hydrogens (e.g., OH groups); methoxyamine hydrochloride (MOX) derivatization MS, or reactive desorption electrospray ionization with hydroxylamine to determine the number of carbonyl groups; and tandem MS (MSn), high-resolution tandem MS (HRMS/MS), and GC-MS to obtain structural details of the steroid ring. From the fragmentation studies, we deduced three major fragmentation rules for this class of sulfated steroids. We also show that a combined MS approach is effective for determining structure of steroid metabolites, with important implications for targeted metabolomics in general and for the study of mouse social communication in particular. PMID:24658800

Visitor center flight room, detail of twin structural piers at ...

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

Visitor center flight room, detail of twin structural piers at northeast corner supporting flight room dome - Wright Brothers National Memorial Visitor Center, Highway 158, Kill Devil Hills, Dare County, NC

15. Detail, cracks evidencing structural failure, northeast rear, view to ...

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

15. Detail, cracks evidencing structural failure, northeast rear, view to southwest, 90mm lens. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

Dynamic Relaxation: A Technique for Detailed Thermo-Elastic Structural Analysis of Transportation Structures

NASA Astrophysics Data System (ADS)

Shoukry, Samir N.; William, Gergis W.; Riad, Mourad Y.; McBride, Kevyn C.

2006-08-01

Dynamic relaxation is a technique developed to solve static problems through an explicit integration in finite element. The main advantage of such a technique is the ability to solve a large problem in a relatively short time compared with the traditional implicit techniques, especially when using nonlinear material models. This paper describes the use of such a technique in analyzing large transportation structures as dowel jointed concrete pavements and 306-m-long, reinforced concrete bridge superstructure under the effect of temperature variations. The main feature of the pavement model is the detailed modeling of dowel bars and their interfaces with the surrounding concrete using extremely fine mesh of solid elements, while in the bridge structure it is the detailed modeling of the girder-deck interface as well as the bracing members between the girders. The 3DFE results were found to be in a good agreement with experimentally measured data obtained from an instrumented pavements sections and a highway bridge constructed in West Virginia. Thus, such a technique provides a good tool for analyzing the response of large structures to static loads in a fraction of the time required by traditional, implicit finite element methods.

16. Detail, looking northwest, of the concrete structure of Trestle ...

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

16. Detail, looking northwest, of the concrete structure of Trestle 16. - Lake Hodges Flume, Along San Dieguito River between Lake Hodges & San Dieguito Reservoir, Rancho Santa Fe, San Diego County, CA

38. Launch Area, Underground Missile Storage Structure, detail of conduit ...

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

38. Launch Area, Underground Missile Storage Structure, detail of conduit service junction - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

12. Exterior detail view of roof structure at eave, showing ...

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

12. Exterior detail view of roof structure at eave, showing exposed rafter tails, skip sheathing and gutter - American Railway Express Company Freight Building, 1060 Northeast Division Street, Bend, Deschutes County, OR

Synthesis, spectroscopic characterizations, crystal structures and DFT studies of nalidixic acid carbonyl hydrazones derivatives

NASA Astrophysics Data System (ADS)

Bergamini, F. R. G.; Ribeiro, M. A.; Lancellotti, M.; Machado, D.; Miranda, P. C. M. L.; Cuin, A.; Formiga, A. L. B.; Corbi, P. P.

2016-09-01

This article describes the synthesis and characterization of the 1-ethyl-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazide (hzd) and six carbonyl hydrazones derivatives of the nalidixic with 1H-pyrrol-2-ylmethylidene (hpyrr), 1H-imidazol-2-ylmethylidene (h2imi), pyridin-2-ylmethylidene (h2py), pyridin-3-ylmethylidene (h3py), pyridin-4-ylmethylidene(h4py) and (2-hydroxyphenyl)methylidene (hsali). The carbonyl hydrazones were characterized by elemental and ESI-QTOF-MS analyses, IR and detailed NMR spectroscopic measurements. The 2D NMR experiments allowed the unambiguous assignment of the hydrogen, carbon and nitrogen atoms, which have not been reported for nalidixic acid carbonyl hydrazone derivatives so far. Crystal structures of hzd and the new carbonyl hydrazones h2imi, hpyrr and h3py were determined by X-ray diffraction studies. Although the synthesis of hzd was reported decades ago, the hzd crystal structure have not been reported yet. Geometric optimizations of all the characterized structures were performed with the aid of DFT studies. Despite the fact that the hydrazones with 2-pyridine carboxylic acid (h2py) and salicyl aldehyde (hsali) were already reported by literature, a detailed spectroscopic study followed by DFT studies are also reported for such compounds in this manuscript. Antimicrobial studies of the compounds are also presented.

37. Launch Area, Underground Missile Storage Structure, detail of personnel ...

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

37. Launch Area, Underground Missile Storage Structure, detail of personnel entrance VIEW NORTH - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

35. MISCELLANEOUS ARCHITECTURAL AND STRUCTURAL DETAILS. INEEL DRAWING NUMBER 200063300287106359. ...

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

35. MISCELLANEOUS ARCHITECTURAL AND STRUCTURAL DETAILS. INEEL DRAWING NUMBER 200-0633-00-287-106359. FLUOR NUMBER 5775-CPP-633-A-9. - Idaho National Engineering Laboratory, Old Waste Calcining Facility, Scoville, Butte County, ID

Detail of antenna tower structure, looking northnorthwest OvertheHorizon Backscatter ...

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

Detail of antenna tower structure, looking north-northwest - Over-the-Horizon Backscatter Radar Network, Tulelake Radar Site Receive Sector Five Antenna Array, Unnamed Road West of Double Head Road, Tulelake, Siskiyou County, CA

Health Monitoring for Airframe Structural Characterization

NASA Technical Reports Server (NTRS)

Munns, Thomas E.; Kent, Renee M.; Bartolini, Antony; Gause, Charles B.; Borinski, Jason W.; Dietz, Jason; Elster, Jennifer L.; Boyd, Clark; Vicari, Larry; Ray, Asok;

A new laboratory-scale experimental facility for detailed aerothermal characterizations of volumetric absorbers

NASA Astrophysics Data System (ADS)

Gomez-Garcia, Fabrisio; Santiago, Sergio; Luque, Salvador; Romero, Manuel; Gonzalez-Aguilar, Jose

2016-05-01

This paper describes a new modular laboratory-scale experimental facility that was designed to conduct detailed aerothermal characterizations of volumetric absorbers for use in concentrating solar power plants. Absorbers are generally considered to be the element with the highest potential for efficiency gains in solar thermal energy systems. The configu-ration of volumetric absorbers enables concentrated solar radiation to penetrate deep into their solid structure, where it is progressively absorbed, prior to being transferred by convection to a working fluid flowing through the structure. Current design trends towards higher absorber outlet temperatures have led to the use of complex intricate geometries in novel ceramic and metallic elements to maximize the temperature deep inside the structure (thus reducing thermal emission losses at the front surface and increasing efficiency). Although numerical models simulate the conjugate heat transfer mechanisms along volumetric absorbers, they lack, in many cases, the accuracy that is required for precise aerothermal validations. The present work aims to aid this objective by the design, development, commissioning and operation of a new experimental facility which consists of a 7 kWe (1.2 kWth) high flux solar simulator, a radiation homogenizer, inlet and outlet collector modules and a working section that can accommodate volumetric absorbers up to 80 mm × 80 mm in cross-sectional area. Experimental measurements conducted in the facility include absorber solid temperature distributions along its depth, inlet and outlet air temperatures, air mass flow rate and pressure drop, incident radiative heat flux, and overall thermal efficiency. In addition, two windows allow for the direct visualization of the front and rear absorber surfaces, thus enabling full-coverage surface temperature measurements by thermal imaging cameras. This paper presents the results from the aerothermal characterization of a siliconized silicon

40. Launch Area, Underground Missile Storage Structure, detail of escape ...

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

40. Launch Area, Underground Missile Storage Structure, detail of escape hatch and decontamination shower VIEW WEST - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

2. DETAIL OF STRUCTURAL SYSTEM FOR CANTILEVERED HOG RUN; BUILDING ...

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

2. DETAIL OF STRUCTURAL SYSTEM FOR CANTILEVERED HOG RUN; BUILDING 168 (1960 HOG KILL) IS BENEATH HOG RUN - Rath Packing Company, Cantilevered Hog Run, Sycamore Street between Elm & Eighteenth Streets, Waterloo, Black Hawk County, IA

42. Launch Area, Underground Missile Storage Structure, detail of escape ...

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

42. Launch Area, Underground Missile Storage Structure, detail of escape hatch, elevator and air vent VIEW SOUTH - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

36. Launch Area, Underground Missile Storage Structure, detail showing elevator, ...

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

36. Launch Area, Underground Missile Storage Structure, detail showing elevator, air ventilators and personnel entrance VIEW SOUTHEAST - NIKE Missile Battery PR-79, Launch Area, East Windsor Road south of State Route 101, Foster, Providence County, RI

14. Detail, crack evidencing structural failure, northeast rear, view to ...

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

14. Detail, crack evidencing structural failure, northeast rear, view to southwest, 90mm lens. Note failure of sandstone lintel above window. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

21. DETAIL OF STRUCTURAL BAY ON NORTH ELEVATION OF BUILDING ...

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

21. DETAIL OF STRUCTURAL BAY ON NORTH ELEVATION OF BUILDING 216 (AMMUNITION MAINTENANCE SHOP) IN ASSEMBLY AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

7. Interior of Building 1015 (land plane hangar), structural detail, ...

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

7. Interior of Building 1015 (land plane hangar), structural detail, looking northeast - Naval Air Station Chase Field, Building 1015, Byrd Street, .82 mile South-southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

8. Interior of Building 1015 (land plane hangar), structural detail, ...

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

8. Interior of Building 1015 (land plane hangar), structural detail, looking northeast - Naval Air Station Chase Field, Building 1015, Byrd Street, .82 mile South-southeast of intersection of Texas State Highway 202 & Independence Street, Beeville, Bee County, TX

Probing the Detailed Seismic Velocity Structure of Subduction Zones Using Advanced Seismic Tomography Methods

NASA Astrophysics Data System (ADS)

Zhang, H.; Thurber, C. H.

2005-12-01

Subduction zones are one of the most important components of the Earth's plate tectonic system. Knowing the detailed seismic velocity structure within and around subducting slabs is vital to understand the constitution of the slab, the cause of intermediate depth earthquakes inside the slab, the fluid distribution and recycling, and tremor occurrence [Hacker et al., 2001; Obara, 2002].Thanks to the ability of double-difference tomography [Zhang and Thurber, 2003] to resolve the fine-scale structure near the source region and the favorable seismicity distribution inside many subducting slabs, it is now possible to characterize the fine details of the velocity structure and earthquake locations inside the slab, as shown in the study of the Japan subduction zone [Zhang et al., 2004]. We further develop the double-difference tomography method in two aspects: the first improvement is to use an adaptive inversion mesh rather than a regular inversion grid and the second improvement is to determine a reliable Vp/Vs structure using various strategies rather than directly from Vp and Vs [see our abstract ``Strategies to solve for a better Vp/Vs model using P and S arrival time'' at Session T29]. The adaptive mesh seismic tomography method is based on tetrahedral diagrams and can automatically adjust the inversion mesh according to the ray distribution so that the inversion mesh nodes are denser where there are more rays and vice versa [Zhang and Thurber, 2005]. As a result, the number of inversion mesh nodes is greatly reduced compared to a regular inversion grid with comparable spatial resolution, and the tomographic system is more stable and better conditioned. This improvement is quite valuable for characterizing the fine structure of the subduction zone considering the highly uneven distribution of earthquakes within and around the subducting slab. The second improvement, to determine a reliable Vp/Vs model, lies in jointly inverting Vp, Vs, and Vp/Vs using P, S, and S

Detailed characterization of low background β-delayed proton detector

NASA Astrophysics Data System (ADS)

Janasik, Molly; Friedman, Moshe; Budner, Tamas; Wrede, Chris

2017-09-01

In order to determine the rates of two important reactions for the astrophysical rapid proton (rp) capture process, a segmented, low background β-delayed proton detector has been built at NSCL. The detector is currently in the process of being optimized. A detailed characterization of the detector's Micromegas pad plane is being performed using measurements with a radioactive 55Fe x-ray calibration source. A fitting routine has been developed to extract the energy resolution from the spectra. First results of detector resolution with P10 gas will be presented. This work is supported by the U.S. National Science Foundation under Award Nos. PHY-1102511 and PHY- 1565546 and the U.S. Department of Energy, Office of Science, under Award No. DE-SC0016052.

11. DETAIL VIEW OF DAM 87, SHOWING STOPLOG STRUCTURE (PARTIALLY ...

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

11. DETAIL VIEW OF DAM 87, SHOWING STOPLOG STRUCTURE (PARTIALLY HIDDEN BY MARSH GRASSES IN LOWER PART OF PHOTO) AT RIGHT (WEST) END OF SPILLWAY - Upper Souris National Wildlife Refuge, Dam 87, Souris River Basin, Foxholm, Surrey (England), ND

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE

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

Pidatala, Venkataramana R.; Mahboubi, Amir; Mortimer, Jenny C.

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharidemore » fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.« less

Structural Characterization of Mannan Cell Wall Polysaccharides in Plants Using PACE

DOE PAGES

Pidatala, Venkataramana R.; Mahboubi, Amir; Mortimer, Jenny C.

2017-10-16

Plant cell wall polysaccharides are notoriously difficult to analyze, and most methods require expensive equipment, skilled operators, and large amounts of purified material. Here, we describe a simple method for gaining detailed polysaccharide structural information, including resolution of structural isomers. For polysaccharide analysis by gel electrophoresis (PACE), plant cell wall material is hydrolyzed with glycosyl hydrolases specific to the polysaccharide of interest (e.g., mannanases for mannan). Large format polyacrylamide gels are then used to separate the released oligosaccharides, which have been fluorescently labeled. Gels can be visualized with a modified gel imaging system (see Table of Materials). The resulting oligosaccharidemore » fingerprint can either be compared qualitatively or, with replication, quantitatively. Linkage and branching information can be established using additional glycosyl hydrolases (e.g., mannosidases and galactosidases). Whilst this protocol describes a method for analyzing glucomannan structure, it can be applied to any polysaccharide for which characterized glycosyl hydrolases exist. Alternatively, it can be used to characterize novel glycosyl hydrolases using defined polysaccharide substrates.« less

18. DETAIL VIEW OF THE HIGH BAY STRUCTURAL SYSTEM AND ...

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

18. DETAIL VIEW OF THE HIGH BAY STRUCTURAL SYSTEM AND WINDOW ILLUMINATION AT THE SHRINK PIT AREA, S END OF B BAY; LOOKING SSE. (Ceronie) - Watervliet Arsenal, Building No. 135, Gillespie Road, South of Parker Road, Watervliet, Albany County, NY

Characterizing the structure of topological insulator thin films

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

Richardella, Anthony; Kandala, Abhinav; Lee, Joon Sue

2015-08-01

We describe the characterization of structural defects that occur during molecular beam epitaxy of topological insulator thin films on commonly used substrates. Twinned domains are ubiquitous but can be reduced by growth on smooth InP (111)A substrates, depending on details of the oxide desorption. Even with a low density of twins, the lattice mismatch between (Bi, Sb){sub 2}Te{sub 3} and InP can cause tilts in the film with respect to the substrate. We also briefly discuss transport in simultaneously top and back electrically gated devices using SrTiO{sub 3} and the use of capping layers to protect topological insulator films frommore » oxidation and exposure.« less

25. DETAIL OF STRUCTURAL TIMBERS, ORE BIN, AND STAIRWAY TO ...

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

25. DETAIL OF STRUCTURAL TIMBERS, ORE BIN, AND STAIRWAY TO TOP FLOOR OF MILL, LOOKING SOUTH FROM SECOND FLOOR OF MILL. PORTION OF ORE BIN ON RIGHT, STAIRS ON LEFT. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

Detailed Characterization of Human Induced Pluripotent Stem Cells Manufactured for Therapeutic Applications.

PubMed

Baghbaderani, Behnam Ahmadian; Syama, Adhikarla; Sivapatham, Renuka; Pei, Ying; Mukherjee, Odity; Fellner, Thomas; Zeng, Xianmin; Rao, Mahendra S

2016-08-01

We have recently described manufacturing of human induced pluripotent stem cells (iPSC) master cell banks (MCB) generated by a clinically compliant process using cord blood as a starting material (Baghbaderani et al. in Stem Cell Reports, 5(4), 647-659, 2015). In this manuscript, we describe the detailed characterization of the two iPSC clones generated using this process, including whole genome sequencing (WGS), microarray, and comparative genomic hybridization (aCGH) single nucleotide polymorphism (SNP) analysis. We compare their profiles with a proposed calibration material and with a reporter subclone and lines made by a similar process from different donors. We believe that iPSCs are likely to be used to make multiple clinical products. We further believe that the lines used as input material will be used at different sites and, given their immortal status, will be used for many years or even decades. Therefore, it will be important to develop assays to monitor the state of the cells and their drift in culture. We suggest that a detailed characterization of the initial status of the cells, a comparison with some calibration material and the development of reporter sublcones will help determine which set of tests will be most useful in monitoring the cells and establishing criteria for discarding a line.

31. Detail of Southeast Light lens and roof structure of ...

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

31. Detail of Southeast Light lens and roof structure of light gallery, 1985. Taken day after Hurricane Gloria, courtesy of Gerald F. Abbott and Block Island Historical Society. - Block Island Southeast Light, Spring Street & Mohegan Trail at Mohegan Bluffs, New Shoreham, Washington County, RI

Detailed Geophysical Fault Characterization in Yucca Flat, Nevada Test Site, Nevada

USGS Publications Warehouse

Asch, Theodore H.; Sweetkind, Donald S.; Burton, Bethany L.; Wallin, Erin L.

2009-01-01

Yucca Flat is a topographic and structural basin in the northeastern part of the Nevada Test Site (NTS) in Nye County, Nevada. Between the years 1951 and 1992, 659 underground nuclear tests took place in Yucca Flat; most were conducted in large, vertical excavations that penetrated alluvium and the underlying Cenozoic volcanic rocks. Radioactive and other potential chemical contaminants at the NTS are the subject of a long-term program of investigation and remediation by the U.S. Department of Energy (DOE), National Nuclear Security Administration, Nevada Site Office, under its Environmental Restoration Program. As part of the program, the DOE seeks to assess the extent of contamination and to evaluate the potential risks to humans and the environment from byproducts of weapons testing. To accomplish this objective, the DOE Environmental Restoration Program is constructing and calibrating a ground-water flow model to predict hydrologic flow in Yucca Flat as part of an effort to quantify the subsurface hydrology of the Nevada Test Site. A necessary part of calibrating and evaluating a model of the flow system is an understanding of the location and characteristics of faults that may influence ground-water flow. In addition, knowledge of fault-zone architecture and physical properties is a fundamental component of the containment of the contamination from underground nuclear tests, should such testing ever resume at the Nevada Test Site. The goal of the present investigation is to develop a detailed understanding of the geometry and physical properties of fault zones in Yucca Flat. This study was designed to investigate faults in greater detail and to characterize fault geometry, the presence of fault splays, and the fault-zone width. Integrated geological and geophysical studies have been designed and implemented to work toward this goal. This report describes the geophysical surveys conducted near two drill holes in Yucca Flat, the data analyses performed, and the

View south; interior structural detail at column A13 south bay ...

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

View south; interior structural detail at column A13 south bay - Naval Base Philadelphia-Philadelphia Naval Shipyard, Foundry-Propeller Shop, North of Porter Avenue, west of Third Street West, Philadelphia, Philadelphia County, PA

Structural Characterization of the Low-Molecular-Weight Heparin Dalteparin by Combining Different Analytical Strategies.

PubMed

Bisio, Antonella; Urso, Elena; Guerrini, Marco; de Wit, Pauline; Torri, Giangiacomo; Naggi, Annamaria

2017-06-24

A number of low molecular weight heparin (LMWH) products are available for clinical use and although all share a similar mechanism of action, they are classified as distinct drugs because of the different depolymerisation processes of the native heparin resulting in substantial pharmacokinetic and pharmacodynamics differences. While enoxaparin has been extensively investigated, little information is available regarding the LMWH dalteparin. The present study is focused on the detailed structural characterization of Fragmin ® by LC-MS and NMR applied both to the whole drug and to its enzymatic products. For a more in-depth approach, size homogeneous octasaccharide and decasaccharide components together with their fractions endowed with high or no affinity toward antithrombin were also isolated and their structural profiles characterized. The combination of different analytical strategies here described represents a useful tool for the assessment of batch-to-batch structural variability and for comparative evaluation of structural features of biosimilar products.

6. Exterior view, showing structural details and instrumentation at the ...

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

6. Exterior view, showing structural details and instrumentation at the walk-in entry level (bottom) of Test Cell 6, Systems Integration Laboratory Building (T-28), looking southwest. - Air Force Plant PJKS, Systems Integration Laboratory, Systems Integration Laboratory Building, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

10. Exterior view, showing the structural details and tanks above ...

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

10. Exterior view, showing the structural details and tanks above at walk-in entry level (bottom) of Test Cell 7, Systems Integration Laboratory Building (T-28), looking west. - Air Force Plant PJKS, Systems Integration Laboratory, Systems Integration Laboratory Building, Waterton Canyon Road & Colorado Highway 121, Lakewood, Jefferson County, CO

Crystal structure of listeriolysin O reveals molecular details of oligomerization and pore formation

NASA Astrophysics Data System (ADS)

Köster, Stefan; van Pee, Katharina; Hudel, Martina; Leustik, Martin; Rhinow, Daniel; Kühlbrandt, Werner; Chakraborty, Trinad; Yildiz, Özkan

2014-04-01

Listeriolysin O (LLO) is an essential virulence factor of Listeria monocytogenes that causes listeriosis. Listeria monocytogenes owes its ability to live within cells to the pH- and temperature-dependent pore-forming activity of LLO, which is unique among cholesterol-dependent cytolysins. LLO enables the bacteria to cross the phagosomal membrane and is also involved in activation of cellular processes, including the modulation of gene expression or intracellular Ca2+ oscillations. Neither the pore-forming mechanism nor the mechanisms triggering the signalling processes in the host cell are known in detail. Here, we report the crystal structure of LLO, in which we identified regions important for oligomerization and pore formation. Mutants were characterized by determining their haemolytic and Ca2+ uptake activity. We analysed the pore formation of LLO and its variants on erythrocyte ghosts by electron microscopy and show that pore formation requires precise interface interactions during toxin oligomerization on the membrane.

Aircraft wing structural detail design (wing, aileron, flaps, and subsystems)

NASA Technical Reports Server (NTRS)

Downs, Robert; Zable, Mike; Hughes, James; Heiser, Terry; Adrian, Kenneth

1993-01-01

The goal of this project was to design, in detail, the wing, flaps, and ailerons for a primary flight trainer. Integrated in this design are provisions for the fuel system, the electrical system, and the fuselage/cabin carry-through interface structure. This conceptual design displays the general arrangement of all major components in the wing structure, taking into consideration the requirements set forth by the appropriate sections of Federal Aviation Regulation Part 23 (FAR23) as well as those established in the statement of work.

Detailed Functional and Proteomic Characterization of Fludarabine Resistance in Mantle Cell Lymphoma Cells

PubMed Central

Lorkova, Lucie; Scigelova, Michaela; Arrey, Tabiwang Ndipanquang; Vit, Ondrej; Pospisilova, Jana; Doktorova, Eliska; Klanova, Magdalena; Alam, Mahmudul; Vockova, Petra; Maswabi, Bokang

2015-01-01

Mantle cell lymphoma (MCL) is a chronically relapsing aggressive type of B-cell non-Hodgkin lymphoma considered incurable by currently used treatment approaches. Fludarabine is a purine analog clinically still widely used in the therapy of relapsed MCL. Molecular mechanisms of fludarabine resistance have not, however, been studied in the setting of MCL so far. We therefore derived fludarabine-resistant MCL cells (Mino/FR) and performed their detailed functional and proteomic characterization compared to the original fludarabine sensitive cells (Mino). We demonstrated that Mino/FR were highly cross-resistant to other antinucleosides (cytarabine, cladribine, gemcitabine) and to an inhibitor of Bruton tyrosine kinase (BTK) ibrutinib. Sensitivity to other types of anti-lymphoma agents was altered only mildly (methotrexate, doxorubicin, bortezomib) or remained unaffacted (cisplatin, bendamustine). The detailed proteomic analysis of Mino/FR compared to Mino cells unveiled over 300 differentially expressed proteins. Mino/FR were characterized by the marked downregulation of deoxycytidine kinase (dCK) and BTK (thus explaining the observed crossresistance to antinucleosides and ibrutinib), but also by the upregulation of several enzymes of de novo nucleotide synthesis, as well as the up-regulation of the numerous proteins of DNA repair and replication. The significant upregulation of the key antiapoptotic protein Bcl-2 in Mino/FR cells was associated with the markedly increased sensitivity of the fludarabine-resistant MCL cells to Bcl-2-specific inhibitor ABT199 compared to fludarabine-sensitive cells. Our data thus demonstrate that a detailed molecular analysis of drug-resistant tumor cells can indeed open a way to personalized therapy of resistant malignancies. PMID:26285204

Structural characterization of terrestrial microbial Mn oxides from Pinal Creek, AZ

USGS Publications Warehouse

Bargar, J.R.; Fuller, C.C.; Marcus, M.A.; Brearley, A.J.; Perez De la Rosa, M.; Webb, S.M.; Caldwell, W.A.

2009-01-01

The microbial catalysis of Mn(II) oxidation is believed to be a dominant source of abundant sorption- and redox-active Mn oxides in marine, freshwater, and subsurface aquatic environments. In spite of their importance, environmental oxides of known biogenic origin have generally not been characterized in detail from a structural perspective. Hyporheic zone Mn oxide grain coatings at Pinal Creek, Arizona, a metals-contaminated stream, have been identified as being dominantly microbial in origin and are well studied from bulk chemistry and contaminant hydrology perspectives. This site thus presents an excellent opportunity to study the structures of terrestrial microbial Mn oxides in detail. XRD and EXAFS measurements performed in this study indicate that the hydrated Pinal Creek Mn oxide grain coatings are layer-type Mn oxides with dominantly hexagonal or pseudo-hexagonal layer symmetry. XRD and TEM measurements suggest the oxides to be nanoparticulate plates with average dimensions on the order of 11 nm thick ?? 35 nm diameter, but with individual particles exhibiting thickness as small as a single layer and sheets as wide as 500 nm. The hydrated oxides exhibit a 10-?? basal-plane spacing and turbostratic disorder. EXAFS analyses suggest the oxides contain layer Mn(IV) site vacancy defects, and layer Mn(III) is inferred to be present, as deduced from Jahn-Teller distortion of the local structure. The physical geometry and structural details of the coatings suggest formation within microbial biofilms. The biogenic Mn oxides are stable with respect to transformation into thermodynamically more stable phases over a time scale of at least 5 months. The nanoparticulate layered structural motif, also observed in pure culture laboratory studies, appears to be characteristic of biogenic Mn oxides and may explain the common occurrence of this mineral habit in soils and sediments. ?? 2008 Elsevier Ltd.

A sedimentological approach to hydrologic characterization: A detailed three-dimensional study of an outcrop of the Sierra Ladrones Formation, Albuquerque basin

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

Lohmann, R.C.

1992-01-01

Three-dimensional geologic outcrop studies which quantitatively describe the geologic architecture of deposits of a specific depositional environment are a necessary requirement for characterization of the permeability structure of an aquifer. The objective of this study is to address this need for quantitative, three-dimensional outcrop studies. For this study, a 10,000 m{sup 2} by 25 m high outcrop of Pliocene-Pleistocene Sierra Ladrones Formation located near Belen, New Mexico was mapped in detail, and the geologic architecture was quantified using geostatistical variogram analysis. In general, the information contained in this study should be useful for hydrologists working on the characterization of aquifersmore » from similar depositional environments such as this one. However, for the permeability correlation study to be truly useful, the within-element correlation structure needs to be superimposed on the elements themselves instead of using mean log (k) values, as was done for this study. Such information is derived from outcrop permeability sampling such as the work of Davis (1990) and Goggin et al. (1988).« less

Crack propagation modelling for high strength steel welded structural details

NASA Astrophysics Data System (ADS)

Mecséri, B. J.; Kövesdi, B.

2017-05-01

Nowadays the barrier of applying HSS (High Strength Steel) material in bridge structures is their low fatigue strength related to yield strength. This paper focuses on the fatigue behaviour of a structural details (a gusset plate connection) made from NSS and HSS material, which is frequently used in bridges in Hungary. An experimental research program is carried out at the Budapest University of Technology and Economics to investigate the fatigue lifetime of this structural detail type through the same test specimens made from S235 and S420 steel grades. The main aim of the experimental research program is to study the differences in the crack propagation and the fatigue lifetime between normal and high strength steel structures. Based on the observed fatigue crack pattern the main direction and velocity of the crack propagation is determined. In parallel to the tests finite element model (FEM) are also developed, which model can handle the crack propagation. Using the measured strain data in the tests and the calculated values from the FE model, the approximation of the material parameters of the Paris law are calculated step-by-step, and their calculated values are evaluated. The same material properties are determined for NSS and also for HSS specimens as well, and the differences are discussed. In the current paper, the results of the experiments, the calculation method of the material parameters and the calculated values are introduced.

STRUCTURAL DETAILS AND SECTIONS OF MAIN PROCESSING BUILDING (CPP601). INL ...

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

STRUCTURAL DETAILS AND SECTIONS OF MAIN PROCESSING BUILDING (CPP-601). INL DRAWING NUMBER 200-0601-00-291-103079. ALTERNATE ID NUMBER 542-11-B-73. - Idaho National Engineering Laboratory, Idaho Chemical Processing Plant, Fuel Reprocessing Complex, Scoville, Butte County, ID

Detailed requirements document for the integrated structural analysis system, phase B

NASA Technical Reports Server (NTRS)

Rainey, J. A.

1976-01-01

The requirements are defined for a software system entitled integrated Structural Analysis System (ISAS) Phase B which is being developed to provide the user with a tool by which a complete and detailed analysis of a complex structural system can be performed. This software system will allow for automated interface with numerous structural analysis batch programs and for user interaction in the creation, selection, and validation of data. This system will include modifications to the 4 functions developed for ISAS, and the development of 25 new functions. The new functions are described.

Evaluating the roles of detailed endocardial structures on right ventricular haemodynamics by means of CFD simulations.

PubMed

Sacco, Federica; Paun, Bruno; Lehmkuhl, Oriol; Iles, Tinen L; Iaizzo, Paul A; Houzeaux, Guillaume; Vázquez, Mariano; Butakoff, Constantine; Aguado-Sierra, Jazmin

2018-06-11

Computational modelling plays an important role in right ventricular (RV) haemodynamic analysis. However, current approaches employ smoothed ventricular anatomies. The aim of this study is to characterise RV haemodynamics including detailed endocardial structures like trabeculae, moderator band and papillary muscles (PMs). Four paired detailed and smoothed RV endocardium models (two male and two female) were reconstructed from ex-vivo human hearts high-resolution magnetic resonance images (MRI). Detailed models include structures with ≥1 mm 2 cross-sectional area. Haemodynamic characterisation was done by computational fluid dynamics (CFD) simulations with steady and transient inflows, using high performance computing (HPC). The differences between the flows in smoothed and detailed models were assessed using Q-criterion for vorticity quantification, the pressure drop between inlet and outlet, and the wall shear stress (WSS). Results demonstrated that detailed endocardial structures increase the degree of intra-ventricular pressure drop, decrease the WSS and disrupt the dominant vortex creating secondary small vortices. Increasingly turbulent blood flow was observed in the detailed RVs. Female RVs were less trabeculated and presented lower pressure drops than the males. In conclusion, neglecting endocardial structures in RV haemodynamic models may lead to inaccurate conclusions about the pressures, stresses, and blood flow behaviour in the cavity. This article is protected by copyright. All rights reserved.

60. DETAIL VIEW OF TWO STEEL STRUCTURAL COLUMNS THAT REPLACED ...

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

60. DETAIL VIEW OF TWO STEEL STRUCTURAL COLUMNS THAT REPLACED THE ORIGINAL BRICK SUPPORTS FOR THE SOUTHERNMOST ARCH ON THE BUILDING'S W WALL WHEN THE S SECTION OF THE BUILDING WAS 'OPENED-UP' DURING THE SECOND WORLD WAR; LOOKING NW. (Ceronie) - Watervliet Arsenal, Building No. 110, Hagner Road between Schull & Whittemore Roads, Watervliet, Albany County, NY

Multiscale Persistent Functions for Biomolecular Structure Characterization

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

Xia, Kelin; Li, Zhiming; Mu, Lin

Here in this paper, we introduce multiscale persistent functions for biomolecular structure characterization. The essential idea is to combine our multiscale rigidity functions (MRFs) with persistent homology analysis, so as to construct a series of multiscale persistent functions, particularly multiscale persistent entropies, for structure characterization. To clarify the fundamental idea of our method, the multiscale persistent entropy (MPE) model is discussed in great detail. Mathematically, unlike the previous persistent entropy (Chintakunta et al. in Pattern Recognit 48(2):391–401, 2015; Merelli et al. in Entropy 17(10):6872–6892, 2015; Rucco et al. in: Proceedings of ECCS 2014, Springer, pp 117–128, 2016), a special resolutionmore » parameter is incorporated into our model. Various scales can be achieved by tuning its value. Physically, our MPE can be used in conformational entropy evaluation. More specifically, it is found that our method incorporates in it a natural classification scheme. This is achieved through a density filtration of an MRF built from angular distributions. To further validate our model, a systematical comparison with the traditional entropy evaluation model is done. Additionally, it is found that our model is able to preserve the intrinsic topological features of biomolecular data much better than traditional approaches, particularly for resolutions in the intermediate range. Moreover, by comparing with traditional entropies from various grid sizes, bond angle-based methods and a persistent homology-based support vector machine method (Cang et al. in Mol Based Math Biol 3:140–162, 2015), we find that our MPE method gives the best results in terms of average true positive rate in a classic protein structure classification test. More interestingly, all-alpha and all-beta protein classes can be clearly separated from each other with zero error only in our model. Finally, a special protein structure index (PSI) is proposed, for

Content, Structure, and Sequence of the Detailing Discipline at Kendall College of Art and Design.

ERIC Educational Resources Information Center

Mulder, Bruce E.

A study identified the appropriate general content, structure, and sequence for a detailing discipline that promoted student achievement to professional levels. Its focus was the detailing discipline, a sequence of studio courses within the furniture design program at Kendall College of Art and Design, Grand Rapids, Michigan. (Detailing, an…

26. DETAIL OF STRUCTURAL COLLAPSE OF TOP FLOOR OF MILL, ...

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

26. DETAIL OF STRUCTURAL COLLAPSE OF TOP FLOOR OF MILL, ABOVE ORE BIN, LOOKING WEST FROM TOP OF STAIRWAY IN CA-290-25. THE PIPE AT CENTER WAS USED TO SPREAD CRUSHED ORE COMING FROM THE JAW CRUSHER EVENLY TO ALL AREA OF THE ORE BIN BELOW. - Skidoo Mine, Park Route 38 (Skidoo Road), Death Valley Junction, Inyo County, CA

5. STANDPIPE STRUCTURE DETAIL SHOWING CONNECTIONS TO PENSTOCKS, RIVETED SECTIONAL ...

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

5. STANDPIPE STRUCTURE DETAIL SHOWING CONNECTIONS TO PENSTOCKS, RIVETED SECTIONAL CONSTRUCTION OF TWO OF THE THREE ORIGINAL STANDPIPES (PHOTO RIGHT), WELDED SECTIONAL CONSTRUCTION OF FOURTH STANDPIPE, AND MODERN VENTILATION VALVES ON FIFTH PENSTOCK AT PHOTO LEFT CENTER BETWEEN FOURTH STANDPIPE AND ORIGINAL TWO. VIEW TO NORTHEAST. - Big Creek Hydroelectric System, Powerhouse 3 Penstock Standpipes, Big Creek, Big Creek, Fresno County, CA

Structure A, architectural sections & details. Drawing no. H2, revised ...

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

Structure A, architectural sections & details. Drawing no. H2, revised as-built dated October 11, 1951. Original drawing by Black & Veatch, consulting engineers, Kansas City, Missouri, prepared for the U.S. Department of the Army, Office of Engineers, Military Construction Division, Washington, D.C. dated October 1. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

DETAIL VIEW, STRUCTURAL TIMBER AND FLOOR JOISTS, SOUTH GARRET. THIS ...

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

DETAIL VIEW, STRUCTURAL TIMBER AND FLOOR JOISTS, SOUTH GARRET. THIS TIMBER IS ONE OF TWO EXTENDING OUT FROM THE HOUSE AND JOINED TO VERTICAL POSTS LOCATED WITHIN THE WOOD TUSCAN COLUMNS LOCATED AT THE PORTICO’S TWO OUTER CORNERS. THE TIMBERS AND THE VISIBLE FLOOR JOISTS WERE PART OF THE HOUSE’S INITIAL CA. 1770 CONSTRUCTION - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

Characterizing Air Pollution Exposure Misclassification Errors Using Detailed Cell Phone Location Data

NASA Astrophysics Data System (ADS)

Yu, H.; Russell, A. G.; Mulholland, J. A.

2017-12-01

In air pollution epidemiologic studies with spatially resolved air pollution data, exposures are often estimated using the home locations of individual subjects. Due primarily to lack of data or logistic difficulties, the spatiotemporal mobility of subjects are mostly neglected, which are expected to result in exposure misclassification errors. In this study, we applied detailed cell phone location data to characterize potential exposure misclassification errors associated with home-based exposure estimation of air pollution. The cell phone data sample consists of 9,886 unique simcard IDs collected on one mid-week day in October, 2013 from Shenzhen, China. The Community Multi-scale Air Quality model was used to simulate hourly ambient concentrations of six chosen pollutants at 3 km spatial resolution, which were then fused with observational data to correct for potential modeling biases and errors. Air pollution exposure for each simcard ID was estimated by matching hourly pollutant concentrations with detailed location data for corresponding IDs. Finally, the results were compared with exposure estimates obtained using the home location method to assess potential exposure misclassification errors. Our results show that the home-based method is likely to have substantial exposure misclassification errors, over-estimating exposures for subjects with higher exposure levels and under-estimating exposures for those with lower exposure levels. This has the potential to lead to a bias-to-the-null in the health effect estimates. Our findings suggest that the use of cell phone data has the potential for improving the characterization of exposure and exposure misclassification in air pollution epidemiology studies.

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING NORTHEAST TOWARD ...

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

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING NORTHEAST TOWARD THE REAR OF THE STRUCTURE. THE WHEELS AT THE TOP OF THE TRAM BUCKETS RODE OFF THE STATIONARY CABLES ONTO THE TRACK SUPPORTED BY THE "C" IRONS SUSPENDED FROM THE TOP TIMBERS, CLEARLY SEEN AT THE TOP OF THE FRAME. THE ANCHOR POINTS FOR THE TWO STATIONARY CABLES ARE AT BOTTOM CENTER, JUST BELOW THE CABLE WHEEL. THE MAIN CABLE WHEEL IS IN THE DISTANCE AT CENTER LEFT. THE ORE CHUTES COMING FROM THE ORE BIN ARE AT LEFT CENTER EDGE. TRAM BUCKETS WERE CHARGED HERE. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

Detail of pier structure and wood fenders of Facility No. ...

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

Detail of pier structure and wood fenders of Facility No. B-1, showing floats in foreground and bollards on pier, view facing east - U.S. Naval Base, Pearl Harbor, South Quay Wall & Repair Wharf, L-shaped portion of quay walls starting at east side of mouth of Dry Dock No. 1, continuing along ocean side of Sixth Street, adjacent to Pier B-2, Pearl City, Honolulu County, HI

Detail View looking at the protected structure and landing gear ...

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

Detail View looking at the protected structure and landing gear housing in the void created by the removal of the Forward Reaction Control System Module from the forward section of the Orbiter Discovery. This view was taken from the service platform in the Orbiter Processing Facility at Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

Characterization of Slosh Damping for Ortho-Grid and Iso-Grid Internal Tank Structures

NASA Technical Reports Server (NTRS)

Westra, Douglas G.; Sansone, Marco D.; Eberhart, Chad J.; West, Jeffrey S.

2016-01-01

Grid stiffened tank structures such as Ortho-Grid and Iso-Grid are widely used in cryogenic tanks for providing stiffening to the tank while reducing mass, compared to tank walls of constant cross-section. If the structure is internal to the tank, it will positively affect the fluid dynamic behavior of the liquid propellant, in regard to fluid slosh damping. As NASA and commercial companies endeavor to explore the solar system, vehicles will by necessity become more mass efficient, and design margin will be reduced where possible. Therefore, if the damping characteristics of the Ortho-Grid and Iso-Grid structure is understood, their positive damping effect can be taken into account in the systems design process. Historically, damping by internal structures has been characterized by rules of thumb and for Ortho-Grid, empirical design tools intended for slosh baffles of much larger cross-section have been used. There is little or no information available to characterize the slosh behavior of Iso-Grid internal structure. Therefore, to take advantage of these structures for their positive damping effects, there is much need for obtaining additional data and tools to characterize them. Recently, the NASA Marshall Space Flight Center conducted both sub-scale testing and computational fluid dynamics (CFD) simulations of slosh damping for Ortho-Grid and Iso-Grid tanks for cylindrical tanks containing water. Enhanced grid meshing techniques were applied to the geometrically detailed and complex Ortho-Grid and Iso-Grid structures. The Loci-STREAM CFD program with the Volume of Fluid Method module for tracking and locating the water-air fluid interface was used to conduct the simulations. The CFD simulations were validated with the test data and new empirical models for predicting damping and frequency of Ortho-Grid and Iso-Grid structures were generated.

Characterization of a Novel Water Pocket Inside the Human Cx26 Hemichannel Structure

PubMed Central

Araya-Secchi, Raul; Perez-Acle, Tomas; Kang, Seung-gu; Huynh, Tien; Bernardin, Alejandro; Escalona, Yerko; Garate, Jose-Antonio; Martínez, Agustin D.; García, Isaac E.; Sáez, Juan C.; Zhou, Ruhong

2014-01-01

Connexins (Cxs) are a family of vertebrate proteins constituents of gap junction channels (GJCs) that connect the cytoplasm of adjacent cells by the end-to-end docking of two Cx hemichannels. The intercellular transfer through GJCs occurs by passive diffusion allowing the exchange of water, ions, and small molecules. Despite the broad interest to understand, at the molecular level, the functional state of Cx-based channels, there are still many unanswered questions regarding structure-function relationships, perm-selectivity, and gating mechanisms. In particular, the ordering, structure, and dynamics of water inside Cx GJCs and hemichannels remains largely unexplored. In this work, we describe the identification and characterization of a believed novel water pocket—termed the IC pocket—located in-between the four transmembrane helices of each human Cx26 (hCx26) monomer at the intracellular (IC) side. Using molecular dynamics (MD) simulations to characterize hCx26 internal water structure and dynamics, six IC pockets were identified per hemichannel. A detailed characterization of the dynamics and ordering of water including conformational variability of residues forming the IC pockets, together with multiple sequence alignments, allowed us to propose a functional role for this cavity. An in vitro assessment of tracer uptake suggests that the IC pocket residue Arg-143 plays an essential role on the modulation of the hCx26 hemichannel permeability. PMID:25099799

Hierarchical structures of amorphous solids characterized by persistent homology

PubMed Central

Hiraoka, Yasuaki; Nakamura, Takenobu; Hirata, Akihiko; Escolar, Emerson G.; Matsue, Kaname; Nishiura, Yasumasa

2016-01-01

This article proposes a topological method that extracts hierarchical structures of various amorphous solids. The method is based on the persistence diagram (PD), a mathematical tool for capturing shapes of multiscale data. The input to the PDs is given by an atomic configuration and the output is expressed as 2D histograms. Then, specific distributions such as curves and islands in the PDs identify meaningful shape characteristics of the atomic configuration. Although the method can be applied to a wide variety of disordered systems, it is applied here to silica glass, the Lennard-Jones system, and Cu-Zr metallic glass as standard examples of continuous random network and random packing structures. In silica glass, the method classified the atomic rings as short-range and medium-range orders and unveiled hierarchical ring structures among them. These detailed geometric characterizations clarified a real space origin of the first sharp diffraction peak and also indicated that PDs contain information on elastic response. Even in the Lennard-Jones system and Cu-Zr metallic glass, the hierarchical structures in the atomic configurations were derived in a similar way using PDs, although the glass structures and properties substantially differ from silica glass. These results suggest that the PDs provide a unified method that extracts greater depth of geometric information in amorphous solids than conventional methods. PMID:27298351

Deployment, Foam Rigidization, and Structural Characterization of Inflatable Thin-Film Booms

NASA Technical Reports Server (NTRS)

Schnell, Andrew R.; Leigh, Larry M., Jr.; Tinker, Michael L.; McConnaughey, Paul R. (Technical Monitor)

2002-01-01

Detailed investigation of the construction, packaging/deployment, foam rigidization, and structural characterization of polyimide film inflatable booms is described. These structures have considerable potential for use in space with solar concentrators, solar sails, space power systems including solar arrays, and other future missions. Numerous thin-film booms or struts were successfully constructed, inflated, injected with foam, and rigidized. Both solid-section and annular test articles were fabricated, using Kapton polyimide film, various adhesives, Styrofoam end plugs, and polyurethane pressurized foam. Numerous inflation/deployment experiments were conducted and compared to computer simulations using the MSC/DYTRAN code. Finite element models were developed for several foam-rigidized struts and compared to model test results. Several problems encountered in the construction, deployment, and foam injection/rigidization process are described. Areas of difficulty included inadequate adhesive strength, cracking of the film arid leakage, excessive bending of the structure during deployment, problems with foam distribution and curing properties, and control of foam leakage following injection into the structure. Many of these problems were overcome in the course of the research.

Detailed electromagnetic simulation for the structural color of butterfly wings.

PubMed

Lee, R Todd; Smith, Glenn S

2009-07-20

Many species of butterflies exhibit interesting optical phenomena due to structural color. The physical reason for this color is subwavelength features on the surface of a single scale. The exposed surface of a scale is covered with a ridge structure. The fully three-dimensional, periodic, finite-difference time-domain method is used to create a detailed electromagnetic model of a generic ridge. A novel method for presenting the three-dimensional observed color pattern is developed. Using these tools, the change in color that is a result of varying individual features of the scale is explored. Computational models are developed that are similar to three butterflies: Morpho rhetenor, Troides magellanus, and Ancyluris meliboeus.

5. "TEST STAND 13, CONCRETE STRUCTURAL SECTIONS AND DETAILS." Specifications ...

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

5. "TEST STAND 1-3, CONCRETE STRUCTURAL SECTIONS AND DETAILS." Specifications No. OC12-50-10; Drawing No. 60-09-06; no sheet number within title block. D.O. SERIES 1109/17, Rev. A. Stamped: AS BUILT; NO CHANGES. Date of Revision A: 11/1/50. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-3, Test Area 1-115, northwest end of Saturn Boulevard, Boron, Kern County, CA

12. "TEST STAND; STRUCTURAL; DEFLECTOR PIT DETAILS, SHEET NO. 1." ...

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

12. "TEST STAND; STRUCTURAL; DEFLECTOR PIT DETAILS, SHEET NO. 1." Specifications No. ENG-04-353-55-72; Drawing No. 60-09-12; sheet 41 of 148; file no. 1320/92, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

9. "TEST STAND; STRUCTURAL; CABLE TUNNEL, PLAN, SECTIONS, DETAILS." Specifications ...

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

9. "TEST STAND; STRUCTURAL; CABLE TUNNEL, PLAN, SECTIONS, DETAILS." Specifications No. OC1-55-72-(Rev.); Drawing No. 60-09-12; sheet 43 of 148; file no. AF 1320/94, Rev. A. Stamped: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

Structure A, reinforcing details. Drawing No. H2302, as built, Original ...

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

Structure A, reinforcing details. Drawing No. H2-302, as built, Original drawing by Black & Veatch, Consulting Engineers, Kansas City, Missouri, prepared for the U.S. Department of the Army, Office of Engineers, Military Construction Division, Washington, D.C. dated October 1, 1951. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

Structural Characterization of Apomyoglobin Self-Associated Species in Aqueous Buffer and Urea Solution

PubMed Central

Chow, Charles; Kurt, Neşe; Murphy, Regina M.; Cavagnero, Silvia

2006-01-01

The biophysical characterization of nonfunctional protein aggregates at physiologically relevant temperatures is much needed to gain deeper insights into the kinetic and thermodynamic relationships between protein folding and misfolding. Dynamic and static laser light scattering have been employed for the detection and detailed characterization of apomyoglobin (apoMb) soluble aggregates populated at room temperature upon dissolving the purified protein in buffer at pH 6.0, both in the presence and absence of high concentrations of urea. Unlike the β-sheet self-associated aggregates previously reported for this protein at high temperatures, the soluble aggregates detected here have either α-helical or random coil secondary structure, depending on solvent and solution conditions. Hydrodynamic diameters range from 80 to 130 nm, with semiflexible chain-like morphology. The combined use of low pH and high urea concentration leads to structural unfolding and complete elimination of the large aggregates. Even upon starting from this virtually monomeric unfolded state, however, protein refolding leads to the formation of severely self-associated species with native-like secondary structure. Under these conditions, kinetic apoMb refolding proceeds via two parallel routes: one leading to native monomer, and the other leading to a misfolded and heavily self-associated state bearing native-like secondary structure. PMID:16214860

Uncovering the Detailed Structure and Dynamics of Andromeda's Complex Stellar Disk

NASA Astrophysics Data System (ADS)

Dorman, Claire; Guhathakurta, Puragra; Seth, Anil; Dalcanton, Julianne; Widrow, Larry; Splash Team, Phat Team

2015-01-01

Lambda cold dark matter (LCDM) cosmology predicts that the disks of Milky Way-mass galaxies should have undergone at least one merger with a large (mass ratio 1:10) satellite in the last several Gyr. However, the stellar disk in the solar neighborhood of the Milky Way is too thin and dynamically cold to have experienced such an impact. The dynamics of the nearby Andromeda galaxy can serve as a second data point, and help us understand whether the Milky Way may simply have had an unusually quiescent merger history, or whether LCDM theory needs to be revisited. Over the last few years, we have carried out a detailed study of the resolved stellar populations in the disk of the Andromeda galaxy using data from two surveys: six-filter Hubble Space Telescope photometry from the recently-completed Panchromatic Hubble Andromeda Treasury (PHAT) survey, and radial velocities derived from Keck/DEIMOS optical spectra obtained as part of the Spectroscopic and Photometric Landscape of Andromeda's Stellar Halo (SPLASH) program. These detailed, multidimensional data sets allow us to decouple the structural subcomponents and characterize them individually. We find that an old, dynamically hot (velocity dispersion ~150 km/s) RGB population extends out to 20 kpc (the edge of the visible disk) but has a disk-like surface brightness profile and luminosity function. This population may have originated in the disk but been kicked out subsequently in impacts with satellite galaxies. We also study the kinematics of the disk as a function of the age of stellar tracers, and find a direct correlation between age and velocity dispersion, indicating that Andromeda has undergone a continuous heating or disk settling process throughout its lifetime. Overall, both the velocity dispersion of Andromeda's disk and the slope of the velocity dispersion vs. stellar age curve are several times those of the Milky Way's, suggesting a more active merger history more in line with LCDM cosmological

115. Stage Level floor structure. Detail of the ends of ...

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

115. Stage Level floor structure. Detail of the ends of three movable stage floor sections. An inclined steel angle track attached to the web of the floor beam allows the sections to roll under the fixed floor. The upper section of the inclined track is hinged so it can be moved upward by a cam mechanism to raise the end of the movable section level with the stage floor. A similar mechanism was used to open and close the floor sections for the star lifts (see sheet 4 of 9, note 6; sheet 8 of 9, details 5, 6A and 6B; sheet 6 of 9, notes 2A, 2B, and 3; and photo IL-1007-120). The pulley, and tongue extending out from the end of the movable section, were used to move the sections back and forth. - Auditorium Building, 430 South Michigan Avenue, Chicago, Cook County, IL

Structure A, protective alarm installation details. Drawing no. H3709, revised ...

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

Structure A, protective alarm installation details. Drawing no. H3-709, revised as-built dated August 28, 1952. Original drawing by Black & Veatch, consulting engineers, Kansas City, Missouri, prepared for the U.S. Department of the Army, Office of Engineers, Military Construction Division, Washington, D.C. dated October 1, 1951. - Travis Air Force Base, Building No. 925, W Street, Fairfield, Solano County, CA

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING SOUTH TOWARD ...

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

DETAIL VIEW OF UPPER TRAM TERMINAL STRUCTURE, LOOKING SOUTH TOWARD THE FRONT OF THE STRUCTURE. THE WHEELS AT THE TOP OF THE TRAM BUCKETS RODE OFF THE STATIONARY CABLES ONTO THE TRACK SUPPORTED BY THE "C" IRONS SUSPENDED FROM THE TOP TIMBERS ON THE LEFT AND RIGHT. THE BUCKET OPENING MECHANISM IS ON THE LEFT, AND PART OF THE CLOSING MECHANISM ON THE RIGHT EDGE OF THE FRAME. THE TWO CABLES AT CENTER ARE THE STATIONARY TRAM CABLES THAT RUN ALONG THE TOP OF THE SUPPORT TOWERS ON WHICH THE WHEELS OF THE TRAM BUCKETS RODE. THEY ARE ANCHORED AT GROUND LEVEL JUST OFF FRAME TO THE LOWER LEFT. - Keane Wonder Mine, Park Route 4 (Daylight Pass Cutoff), Death Valley Junction, Inyo County, CA

Materials-by-design: computation, synthesis, and characterization from atoms to structures

NASA Astrophysics Data System (ADS)

Yeo, Jingjie; Jung, Gang Seob; Martín-Martínez, Francisco J.; Ling, Shengjie; Gu, Grace X.; Qin, Zhao; Buehler, Markus J.

2018-05-01

In the 50 years that succeeded Richard Feynman’s exposition of the idea that there is ‘plenty of room at the bottom’ for manipulating individual atoms for the synthesis and manufacturing processing of materials, the materials-by-design paradigm is being developed gradually through synergistic integration of experimental material synthesis and characterization with predictive computational modeling and optimization. This paper reviews how this paradigm creates the possibility to develop materials according to specific, rational designs from the molecular to the macroscopic scale. We discuss promising techniques in experimental small-scale material synthesis and large-scale fabrication methods to manipulate atomistic or macroscale structures, which can be designed by computational modeling. These include recombinant protein technology to produce peptides and proteins with tailored sequences encoded by recombinant DNA, self-assembly processes induced by conformational transition of proteins, additive manufacturing for designing complex structures, and qualitative and quantitative characterization of materials at different length scales. We describe important material characterization techniques using numerous methods of spectroscopy and microscopy. We detail numerous multi-scale computational modeling techniques that complements these experimental techniques: DFT at the atomistic scale; fully atomistic and coarse-grain molecular dynamics at the molecular to mesoscale; continuum modeling at the macroscale. Additionally, we present case studies that utilize experimental and computational approaches in an integrated manner to broaden our understanding of the properties of two-dimensional materials and materials based on silk and silk-elastin-like proteins.

9. DETAIL OF DIVERSION STRUCTURE WEST OF DERBY LAKE (SECTION ...

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

9. DETAIL OF DIVERSION STRUCTURE WEST OF DERBY LAKE (SECTION 2) SHOWING DIVERSION GATE TO LAKE LADORA. - Highline Canal, Sand Creek Lateral, Beginning at intersection of Peoria Street & Highline Canal in Arapahoe County (City of Aurora), Sand Creek lateral Extends 15 miles Northerly through Araphoe County, City & County of Denver, & Adams County to its end point, approximately 1/4 mile Southest of intersectioin of D Street & Ninth Avenue in Adams County (Rocky Mountain Arsenal, Commerce City Vicinity), Commerce City, Adams County, CO

Detailed Structural Analyses of KOH Activated Carbon from Waste Coffee Beans

NASA Astrophysics Data System (ADS)

Takahata, Tomokazu; Toda, Ikumi; Ono, Hiroki; Ohshio, Shigeo; Akasaka, Hiroki; Himeno, Syuji; Kokubu, Toshinori; Saitoh, Hidetoshi

2009-11-01

The relationship of the detailed structural change of KOH activated carbon and hydrogen storage ability was investigated in activated carbon materials fabricated from waste coffee beans. The specific surface area of porous carbon materials calculated from N2 adsorption isotherms stood at 2070 m2/g when the weight ratio of KOH to carbon materials was 5:1, and pore size was in the range of approximately 0.6 to 1.1 nm as micropores. In the structural analysis, X-ray diffraction analysis and Raman spectroscopy indicated structural change in these carbon materials through KOH activation. The order of the graphite structure changed to a smaller scale with this activation. It is theorized that specific surface area increased using micropores provided by carbon materials developed from the descent of the graphite structure. Hydrogen storage ability improved with these structural changes, and reached 0.6 wt % at 2070 m2/g. These results suggest that hydrogen storage ability is conferred by the chemical effect on graphite of carbon materials.

Structure, functional characterization, and evolution of the dihydroorotase domain of human CAD.

PubMed

Grande-García, Araceli; Lallous, Nada; Díaz-Tejada, Celsa; Ramón-Maiques, Santiago

2014-02-04

Upregulation of CAD, the multifunctional protein that initiates and controls the de novo biosynthesis of pyrimidines in animals, is essential for cell proliferation. Deciphering the architecture and functioning of CAD is of interest for its potential usage as an antitumoral target. However, there is no detailed structural information about CAD other than that it self-assembles into hexamers of ∼1.5 MDa. Here we report the crystal structure and functional characterization of the dihydroorotase domain of human CAD. Contradicting all assumptions, the structure reveals an active site enclosed by a flexible loop with two Zn²⁺ ions bridged by a carboxylated lysine and a third Zn coordinating a rare histidinate ion. Site-directed mutagenesis and functional assays prove the involvement of the Zn and flexible loop in catalysis. Comparison with homologous bacterial enzymes supports a reclassification of the DHOase family and provides strong evidence against current models of the architecture of CAD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Structural characterization of metal binding to a cold-adapted frataxin.

PubMed

Noguera, Martín E; Roman, Ernesto A; Rigal, Juan B; Cousido-Siah, Alexandra; Mitschler, André; Podjarny, Alberto; Santos, Javier

2015-06-01

Frataxin is an evolutionary conserved protein that participates in iron metabolism. Deficiency of this small protein in humans causes a severe neurodegenerative disease known as Friedreich's ataxia. A number of studies indicate that frataxin binds iron and regulates Fe-S cluster biosynthesis. Previous structural studies showed that metal binding occurs mainly in a region of high density of negative charge. However, a comprehensive characterization of the binding sites is required to gain further insights into the mechanistic details of frataxin function. In this work, we have solved the X-ray crystal structures of a cold-adapted frataxin from a psychrophilic bacterium in the presence of cobalt or europium ions. We have identified a number of metal-binding sites, mainly solvent exposed, several of which had not been observed in previous studies on mesophilic homologues. No major structural changes were detected upon metal binding, although the structures exhibit significant changes in crystallographic B-factors. The analysis of these B-factors, in combination with crystal packing and RMSD among structures, suggests the existence of localized changes in the internal motions. Based on these results, we propose that bacterial frataxins possess binding sites of moderate affinity for a quick capture and transfer of iron to other proteins and for the regulation of Fe-S cluster biosynthesis, modulating interactions with partner proteins.

12. "OBSERVATION POSTS, STRUCTURAL PLANS AND DETAILS." Specifications No. OC25572; ...

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

12. "OBSERVATION POSTS, STRUCTURAL PLANS AND DETAILS." Specifications No. OC2-55-72; Drawing No. 60-09-12; sheet 89 of 148; file no. 1321/40, Rev. A. Very faint stamp above note reads: RECORD DRAWING - AS CONSTRUCTED. Below stamp: Contract no. 4338, no change. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Observation Bunkers for Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

Structural Characterization of Core Region in Erwinia amylovora Lipopolysaccharide.

PubMed

Casillo, Angela; Ziaco, Marcello; Lindner, Buko; Merino, Susana; Mendoza-Barberá, Elena; Tomás, Juan M; Corsaro, Maria Michela

2017-03-04

Erwinia amylovora ( E. amylovora ) is the first bacterial plant pathogen described and demonstrated to cause fire blight, a devastating plant disease affecting a wide range of species including a wide variety of Rosaceae . In this study, we reported the lipopolysaccharide (LPS) core structure from E. amylovora strain CFBP1430, the first one for an E. amylovora highly pathogenic strain. The chemical characterization was performed on the mutants waaL (lacking only the O-antigen LPS with a complete LPS-core), wabH and wabG (outer-LPS core mutants). The LPSs were isolated from dry cells and analyzed by means of chemical and spectroscopic methods. In particular, they were subjected to a mild acid hydrolysis and/or a hydrazinolysis and investigated in detail by one and two dimensional Nuclear Magnetic Resonance (NMR) spectroscopy and ElectroSpray Ionization Fourier Transform-Ion Cyclotron Resonance (ESI FT-ICR) mass spectrometry.

Characterization of structures of the Nankai Trough accretionary prism from integrated analyses of LWD log response, resistivity images and clay mineralogy of cuttings: Expedition 338 Site C0002

NASA Astrophysics Data System (ADS)

Jurado, Maria Jose; Schleicher, Anja

2014-05-01

The objective of our research is a detailed characterization of structures on the basis of LWD oriented images and logs,and clay mineralogy of cuttings from Hole C0002F of the Nankai Trough accretionary prism. Our results show an integrated interpretation of structures derived from borehole images, petrophysical characterization on LWD logs and cuttings mineralogy. The geometry of the structure intersected at Hole C0002F has been characterized by the interpretation of oriented borehole resistivity images acquired during IODP Expedition 338. The characterization of structural features, faults and fracture zones is based on a detailed post-cruise interpretation of bedding and fractures on borehole images and also on the analysis of Logging While Drilling (LWD) log response (gamma radioactivity, resistivity and sonic logs). The interpretation and complete characterization of structures (fractures, fracture zones, fault zones, folds) was achieved after detailed shorebased reprocessing of resistivity images, which allowed to enhance bedding and fracture's imaging for geometry and orientation interpretation. In order to characterize distinctive petrophysical properties based on LWD log response, it could be compared with compositional changes derived from cuttings analyses. Cuttings analyses were used to calibrate and to characterize log response and to verify interpretations in terms of changes in composition and texture at fractures and fault zones defined on borehole images. Cuttings were taken routinely every 5 m during Expedition 338, indicating a clay-dominated lithology of silty claystone with interbeds of weakly consolidated, fine sandstones. The main mineralogical components are clay minerals, quartz, feldspar and calcite. Selected cuttings were taken from areas of interest as defined on LWD logs and images. The clay mineralogy was investigated on the <2 micron clay-size fraction, with special focus on smectite and illite minerals. Based on X-ray diffraction

Detailed temporal structure of communication networks in groups of songbirds.

PubMed

Stowell, Dan; Gill, Lisa; Clayton, David

2016-06-01

Animals in groups often exchange calls, in patterns whose temporal structure may be influenced by contextual factors such as physical location and the social network structure of the group. We introduce a model-based analysis for temporal patterns of animal call timing, originally developed for networks of firing neurons. This has advantages over cross-correlation analysis in that it can correctly handle common-cause confounds and provides a generative model of call patterns with explicit parameters for the influences between individuals. It also has advantages over standard Markovian analysis in that it incorporates detailed temporal interactions which affect timing as well as sequencing of calls. Further, a fitted model can be used to generate novel synthetic call sequences. We apply the method to calls recorded from groups of domesticated zebra finch (Taeniopygia guttata) individuals. We find that the communication network in these groups has stable structure that persists from one day to the next, and that 'kernels' reflecting the temporal range of influence have a characteristic structure for a calling individual's effect on itself, its partner and on others in the group. We further find characteristic patterns of influences by call type as well as by individual. © 2016 The Authors.

Structural and compositional characterization of the adhesive produced by reef building oysters.

PubMed

Alberts, Erik M; Taylor, Stephen D; Edwards, Stephanie L; Sherman, Debra M; Huang, Chia-Ping; Kenny, Paul; Wilker, Jonathan J

2015-04-29

Oysters have an impressive ability to overcome difficulties of life within the stressful intertidal zone. These shellfish produce an adhesive for attaching to each other and building protective reef communities. With their reefs often exceeding kilometers in length, oysters play a major role in balancing the health of coastal marine ecosystems. Few details are available to describe oyster adhesive composition or structure. Here several characterization methods were applied to describe the nature of this material. Microscopy studies indicated that the glue is comprised of organic fiber-like and sheet-like structures surrounded by an inorganic matrix. Phospholipids, cross-linking chemistry, and conjugated organics were found to differentiate this adhesive from the shell. Symbiosis in material synthesis could also be present, with oysters incorporating bacterial polysaccharides into their adhesive. Oyster glue shows that an organic-inorganic composite material can provide adhesion, a property especially important when constructing a marine ecosystem.

Characterization of a bio-oil from pyrolysis of rice husk by detailed compositional analysis and structural investigation of lignin.

PubMed

Lu, Yao; Wei, Xian-Yong; Cao, Jing-Pei; Li, Peng; Liu, Fang-Jing; Zhao, Yun-Peng; Fan, Xing; Zhao, Wei; Rong, Liang-Ce; Wei, Yan-Bin; Wang, Shou-Ze; Zhou, Jun; Zong, Zhi-Min

2012-07-01

Detailed compositional analysis of a bio-oil (BO) from pyrolysis of rice husk was carried out. The BO was extracted sequentially with n-hexane, CCl(4), CS(2), benzene and CH(2)Cl(2). In total, 167 organic species were identified with GC/MS in the extracts and classified into alkanes, alcohols, hydroxybenzenes, alkoxybenzenes, dioxolanes, aldehydes, ketones, carboxylic acids, esters, nitrogen-containing organic compounds and other species. The benzene ring-containing species (BRCCs) were attributed to the degradation of lignin while most of the rests were derived from the degradation of cellulose and hemicellulose. Along with guaiacyl and p-hydroxyphenyl units as the main components, a new type of linkage was suggested, i.e., C(ar)-CH(2)-C(ar) in 4,4'-methylenebis(2,6-dimethoxyphenol). Based on the species identified, a possible macromolecular structure of the lignin and the mechanism for its pyrolysis are proposed. The BO was also extracted with petroleum ether in ca. 17.8% of the extract yield and about 82.1% of the extracted components are BRCCs. Copyright © 2012 Elsevier Ltd. All rights reserved.

EDITORIAL: (Nano)characterization of semiconductor materials and structures (Nano)characterization of semiconductor materials and structures

NASA Astrophysics Data System (ADS)

Bonanni, Alberta

2011-06-01

The latest impressive advancements in the epitaxial fabrication of semiconductors and in the refinement of characterization techniques have the potential to allow insight into the deep relation between materials' structural properties and their physical and chemical functionalities. Furthermore, while the comprehensive (nano)characterization of semiconductor materials and structures is becoming more and more necessary, a compendium of the currently available techniques is lacking. We are positive that an overview of the hurdles related to the specific methods, often leading to deceptive interpretations, will be most informative for the broad community working on semiconductors, and will help in shining some light onto a plethora of controversial reports found in the literature. From this perspective, with this special issue we address and highlight the challenges and misinterpretations related to complementary local (nanoscale) and more global experimental methods for the characterization of semiconductors. The six topical reviews and the three invited papers by leading experts in the specific fields collected in here are intended to provide the required broad overview on the possibilities of actual (nano)characterization methods, from the microscopy of single quantum structures, over the synchrotron-based absorption and diffraction of nano-objects, to the contentious detection of tiny magnetic signals by quantum interference and resonance techniques. We are grateful to all the authors for their valuable contributions. Moreover, I would like to thank the Editorial Board of the journal for supporting the realization of this special issue and for inviting me to serve as Guest Editor. We greatly appreciate the work of the reviewers, of the editorial staff of Semiconductor Science and Technology and of IOP Publishing. In particular, the efforts of Alice Malhador in coordinating this special issue are acknowledged.

Characterization of adhesive from oysters: A structural and compositional study

NASA Astrophysics Data System (ADS)

Alberts, Erik

The inability for man-made adhesives to set in wet or humid environments is an ongoing challenging the design of biomedical and marine adhesive materials. However, we see that nature has already overcome this challenge. Mussels, barnacles, oysters and sandcastle worms all have unique mechanisms by which they attach themselves to surfaces. By understanding what evolution has already spent millions of years perfecting, we can design novel adhesive materials inspired by nature's elegant designs. The well-studied mussel is currently the standard for design of marine inspired biomimetic polymers. In the work presented here, we aim to provide new insights into the adhesive produced by the eastern oyster, Crassostrea virginica. Unlike the mussel, which produces thread-like plaques comprised of DOPA containing-protein, the oyster secretes an organic-inorganic hybrid adhesive as it settles and grows onto a surface. This form of adhesion renders the oyster to be permanently fixed in place. Over time, hundreds of thousands of oyster grow and agglomerate to form extensive reef structures. These reefs are not only essential to survival of the oyster, but are also vital to intertidal ecosystems. While the shell of the oyster has been extensively studied, curiously, only a few conflicting insights have been made into the nature of the adhesive and contact zone between shell and substrate, and even lesfs information has been ascertained on organic and inorganic composition. In this work, we provide microscopy and histochemical studies to characterize the structure and composition of the adhesive, using oyster in the adult and juvenile stages of life. Preliminary work on extracting and characterizing organic components through collaborative help with solid-state NMR (SSNMR) and proteomics are also detailed here. We aim to provide a full, comprehensive characterization of oyster adhesive so that in the future, we may apply what we learn to the design of new materials.

NMR Crystallography of Enzyme Active Sites: Probing Chemically-Detailed, Three-Dimensional Structure in Tryptophan Synthase

PubMed Central

Dunn, Michael F.

2013-01-01

Conspectus NMR crystallography – the synergistic combination of X-ray diffraction, solid-state NMR spectroscopy, and computational chemistry – offers unprecedented insight into three-dimensional, chemically-detailed structure. From its initial role in refining diffraction data of organic and inorganic solids, NMR crystallography is now being developed for application to active sites in biomolecules, where it reveals chemically-rich detail concerning the interactions between enzyme site residues and the reacting substrate that is not achievable when X-ray, NMR, or computational methodologies are applied in isolation. For example, typical X-ray crystal structures (1.5 to 2.5 Å resolution) of enzyme-bound intermediates identify possible hydrogen-bonding interactions between site residues and substrate, but do not directly identify the protonation state of either. Solid-state NMR can provide chemical shifts for selected atoms of enzyme-substrate complexes, but without a larger structural framework in which to interpret them, only empirical correlations with local chemical structure are possible. Ab initio calculations and molecular mechanics can build models for enzymatic processes, but rely on chemical details that must be specified. Together, however, X-ray diffraction, solid-state NMR spectroscopy, and computational chemistry can provide consistent and testable models for structure and function of enzyme active sites: X-ray crystallography provides a coarse framework upon which models of the active site can be developed using computational chemistry; these models can be distinguished by comparison of their calculated NMR chemical shifts with the results of solid-state NMR spectroscopy experiments. Conceptually, each technique is a puzzle piece offering a generous view of the big picture. Only when correctly pieced together, however, can they reveal the big picture at highest resolution. In this Account, we detail our first steps in the development of NMR

Characterization and Quantification of the Pore Structures of the Shale Oil Reservoir Formations in Multiscale

NASA Astrophysics Data System (ADS)

Liu, K.; Ostadhassan, M.

2016-12-01

Due to the fast development of hydraulic fracturing and horizontal drilling, shale formations now are one important resource of energy in North America. Characterizing the pore structure of these shale formations is of critical importance in understanding the original oil/gas in place and also the flow properties of the rock matrix. Pore with different properties such as pore size and pore shape can impact the physical, mechanical and chemical properties including strength, elastic modulus, permeability and conductivity. Nowadays, image analysis has been a robust method to quantify the pore information from the porous medium.SEM has been one of the most useful tools to study the pore microstructures due to its high depth of focus which can provide detailed topographical information about the surface. The suitable difference between solid matrix and pores due to the different gray level pixels can be used to study the pore structures.In this paper, we characterized and quantified the pore structures of rock samples from Middle Bakken Formation which is a typical unconventional reservoir in North America. High resolution SEM images of five samples we chose based on the gamma logs were derived after sample preparation. After determining the threshold of the images, we extracted the pore spaces. Then we analyzed the pore structures properties such as pore size distributions and pore shape distributions of the five samples and compared based on their mineral compositions. After that, we analyzed their heterogeneity and isotropy properties which have been identified as an important factor affecting reservoir productivity. Finally, we studied the impact of scale effect on the pore structures characterization.

AFM Structural Characterization of Drinking Water Biofilm ...

EPA Pesticide Factsheets

Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodology will allow future in situ investigations to temporally monitor mixed culture drinking water biofilm structural changes during disinfection treatments. Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air and aqueous solution. Operating parameters were optimized to improve imaging of structural details for a mature biofilm in liquid. By using a soft cantilever (0.03 N/m) and slow scan rate (0.5 Hz), biofilm and individual bacterial cell’s structural topography were resolved and continuously imaged in liquid without loss of spatial resolution or sample damage. The developed methodo

Structural Characterization of Sm(III)(EDTMP).

PubMed

Yang, Y; Pushie, M J; Cooper, D M L; Doschak, M R

2015-11-02

Samarium-153 ethylenediamine-N,N,N',N'-tetrakis(methylenephosphonic acid) ((153)Sm-EDTMP, or samarium lexidronam), also known by its registered trademark name Quadramet, is an approved therapeutic radiopharmaceutical used in the palliative treatment of painful bone metastases. Typically, patients with prostate, breast, or lung cancer are most likely to go on to require bone pain palliation treatment due to bone metastases. Sm(EDTMP) is a bone-seeking drug which accumulates on rapidly growing bone, thereby delivering a highly region-specific dose of radiation, chiefly through β particle emission. Even with its widespread clinical use, the structure of Sm(EDTMP) has not yet been characterized at atomic resolution, despite attempts to crystallize the complex. Herein, we prepared a 1:1 complex of the cold (stable isotope) of Sm(EDTMP) under alkaline conditions and then isolated and characterized the complex using conventional spectroscopic techniques, as well as with extended X-ray absorption fine structure (EXAFS) spectroscopy and density functional structure calculations, using natural abundance Sm. We present the atomic resolution structure of [Sm(III)(EDTMP)-8H](5-) for the first time, supported by the EXAFS data and complementary spectroscopic techniques, which demonstrate that the samarium coordination environment in solution is in agreement with the structure that has long been conjectured.

Functional and Structural Characterization of a (+)-Limonene Synthase from Citrus sinensis.

PubMed

Morehouse, Benjamin R; Kumar, Ramasamy P; Matos, Jason O; Olsen, Sarah Naomi; Entova, Sonya; Oprian, Daniel D

2017-03-28

Terpenes make up the largest and most diverse class of natural compounds and have important commercial and medical applications. Limonene is a cyclic monoterpene (C 10 ) present in nature as two enantiomers, (+) and (-), which are produced by different enzymes. The mechanism of production of the (-)-enantiomer has been studied in great detail, but to understand how enantiomeric selectivity is achieved in this class of enzymes, it is important to develop a thorough biochemical description of enzymes that generate (+)-limonene, as well. Here we report the first cloning and biochemical characterization of a (+)-limonene synthase from navel orange (Citrus sinensis). The enzyme obeys classical Michaelis-Menten kinetics and produces exclusively the (+)-enantiomer. We have determined the crystal structure of the apoprotein in an "open" conformation at 2.3 Å resolution. Comparison with the structure of (-)-limonene synthase (Mentha spicata), which is representative of a fully closed conformation (Protein Data Bank entry 2ONG ), reveals that the short H-α1 helix moves nearly 5 Å inward upon substrate binding, and a conserved Tyr flips to point its hydroxyl group into the active site.

Nondestructive Structural Damage Detection in Flexible Space Structures Using Vibration Characterization

NASA Technical Reports Server (NTRS)

Ricles, James M.

1991-01-01

Spacecraft are susceptible to structural damage over their operating life from impact, environmental loads, and fatigue. Structural damage that is not detected and not corrected may potentially cause more damage and eventually catastrophic structural failure. NASA's current fleet of reusable spacecraft, namely the Space Shuttle, has been flown on several missions. In addition, configurations of future NASA space structures, e.g. Space Station Freedom, are larger and more complex than current structures, making them more susceptible to damage as well as being more difficult to inspect. Consequently, a reliable structural damage detection capability is essential to maintain the flight safety of these structures. Visual inspections alone can not locate impending material failure (fatigue cracks, yielding); it can only observe post-failure situations. An alternative approach is to develop an inspection and monitoring system based on vibration characterization that assesses the integrity of structural and mechanical components. A methodology for detecting structural damage is presented. This methodology is based on utilizing modal test data in conjunction with a correlated analytical model of the structure to: (1) identify the structural dynamic characteristics (resonant frequencies and mode shapes) from measurements of ambient motions and/or force excitation; (2) calculate modal residual force vectors to identify the location of structural damage; and (3) conduct a weighted sensitivity analysis in order to assess the extent of mass and stiffness variations, where structural damage is characterized by stiffness reductions. The approach is unique from other existing approaches in that varying system mass and stiffness, mass center locations, the perturbation of both the natural frequencies and mode shapes, and statistical confidence factors for structural parameters and experimental instrumentation are all accounted for directly.

Towards a detailed anthropometric body characterization using the Microsoft Kinect.

PubMed

Domingues, Ana; Barbosa, Filipa; Pereira, Eduardo M; Santos, Márcio Borgonovo; Seixas, Adérito; Vilas-Boas, João; Gabriel, Joaquim; Vardasca, Ricardo

2016-01-01

Anthropometry has been widely used in different fields, providing relevant information for medicine, ergonomics and biometric applications. However, the existent solutions present marked disadvantages, reducing the employment of this type of evaluation. Studies have been conducted in order to easily determine anthropometric measures considering data provided by low-cost sensors, such as the Microsoft Kinect. In this work, a methodology is proposed and implemented for estimating anthropometric measures considering the information acquired with this sensor. The measures obtained with this method were compared with the ones from a validation system, Qualisys. Comparing the relative errors determined with state-of-art references, for some of the estimated measures, lower errors were verified and a more complete characterization of the whole body structure was achieved.

Imaging the internal structure of fluid upflow zones with detailed digital Parasound echosounder surveys

NASA Astrophysics Data System (ADS)

Spiess, V.; Zuehlsdorff, L.; von Lom-Keil, H.; Schwenk, T.

2001-12-01

Sites of venting fluids both with continuous and episodic supply often reveal complex surface and internal structures, which are difficult to image and cause problems to transfer results from local sampling towards a structural reconstruction and a quantification of (average) flux rates. Detailed acoustic and seismic surveys would be required to retrieve this information, but also an appropriate environment, where fluid migration can be properly imaged from contrasts to unaffected areas. Hemipelagic sediments are most suitable, since typically reflectors are coherent and of low lateral amplitude variation and structures are continuous over distances much longer than the scale of fluid migration features. During RV Meteor Cruise M473 and RV Sonne Cruise SO 149 detailed studies were carried out in the vicinity of potential fluid upflow zones in the Lower Congo Basin at 5oS in 3000 m water depth and at the Northern Cascadia Margin in 1000 m water depth. Unexpected sampling of massive gas hydrates from the sea floor as well as of carbonate concretions, shell fragments and different liveforms indicated active fluid venting in a typically hemipelagic realm. The acoustic signature of such zones includes columnar blanking, pockmark depressions at the sea floor, association with small offset faults (< 1m). A dedicated survey with closely spaced grid lines was carried out with the Parasound sediment echosounder (4 kHz), which data were digitally acquired with the ParaDigMA System for further processing and display, to image the spatial structure of the upflow zones. Due to the high data density amplitudes and other acoustic properties could be investigated in a 3D volume and time slices as well as reflector surfaces were analyzed. Pronounced lateral variations of reflection amplitudes within a complex pattern indicate potential pathways for fluid/gas migration and occurrences of near-surface gas hydrate deposits, which may be used to trace detailed surface evidence from side

Detailed characterization of particulate matter emitted by lean-burn gasoline direct injection engine

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

Zelenyuk, Alla; Wilson, Jacqueline; Imre, Dan

This study presents detailed characterization of the chemical and physical properties of PM emitted by a 2.0L BMW lean-burn turbocharged GDI engine operated under a number of combustion strategies that include lean homogeneous, lean stratified, stoichiometric, and fuel rich conditions. We characterized PM number concentrations, size distributions, and the size, mass, compositions, and effective density of fractal and compact individual exhaust particles. For the fractal particles, these measurements yielded fractal dimension, average diameter of primary spherules, and number of spherules, void fraction, and dynamic shape factors as function of particle size. Overall, the PM properties were shown to vary significantlymore » with engine operation condition. Lean stratified operation yielded the most diesel-like size distribution and the largest PM number and mass concentrations, with nearly all particles being fractal agglomerates composed of elemental carbon with small amounts of ash and organics. In contrast, stoichiometric operation yielded a larger fraction of ash particles, especially at low speed and low load. Three distinct forms of ash particles were observed, with their fractions strongly dependent on engine operating conditions: sub-50 nm ash particles, abundant at low speed and low load, ash-containing fractal particles, and large compact ash particles that significantly contribute to PM mass loadings« less

Experiments In Characterizing Vibrations Of A Structure

NASA Technical Reports Server (NTRS)

Yam, Yeung; Hadaegh, Fred Y.; Bayard, David S.

1993-01-01

Report discusses experiments conducted to test methods of identification of vibrational and coupled rotational/vibrational modes of flexible structure. Report one in series that chronicle development of integrated system of methods, sensors, actuators, analog and digital signal-processing equipment, and algorithms to suppress vibrations in large, flexible structure even when dynamics of structure partly unknown and/or changing. Two prior articles describing aspects of research, "Autonomous Frequency-Domain Indentification" (NPO-18099), and "Automated Characterization Of Vibrations Of A Structure" (NPO-18141).

Structure of dehaloperoxidase B at 1.58 Å resolution and structural characterization of the AB dimer from Amphitrite ornata

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

de Serrano, Vesna; D; Antonio, Jennifer

2012-04-18

As members of the globin superfamily, dehaloperoxidase (DHP) isoenzymes A and B from the marine annelid Amphitrite ornata possess hemoglobin function, but they also exhibit a biologically relevant peroxidase activity that is capable of converting 2,4,6-trihalophenols to the corresponding 2,6-dihaloquinones in the presence of hydrogen peroxide. Here, a comprehensive structural study of recombinant DHP B, both by itself and cocrystallized with isoenzyme A, using X-ray diffraction is presented. The structure of DHP B refined to 1.58 {angstrom} resolution exhibits the same distal histidine (His55) conformational flexibility as that observed in isoenzyme A, as well as additional changes to the distalmore » and proximal hydrogen-bonding networks. Furthermore, preliminary characterization of the DHP AB heterodimer is presented, which exhibits differences in the AB interface that are not observed in the A-only or B-only homodimers. These structural investigations of DHP B provide insights that may relate to the mechanistic details of the H{sub 2}O{sub 2}-dependent oxidative dehalogenation reaction catalyzed by dehaloperoxidase, present a clearer description of the function of specific residues in DHP at the molecular level and lead to a better understanding of the paradigms of globin structure-function relationships.« less

Non-Linear Structural Dynamics Characterization using a Scanning Laser Vibrometer

NASA Technical Reports Server (NTRS)

Pai, P. F.; Lee, S.-Y.

2003-01-01

This paper presents the use of a scanning laser vibrometer and a signal decomposition method to characterize non-linear dynamics of highly flexible structures. A Polytec PI PSV-200 scanning laser vibrometer is used to measure transverse velocities of points on a structure subjected to a harmonic excitation. Velocity profiles at different times are constructed using the measured velocities, and then each velocity profile is decomposed using the first four linear mode shapes and a least-squares curve-fitting method. From the variations of the obtained modal \\ielocities with time we search for possible non-linear phenomena. A cantilevered titanium alloy beam subjected to harmonic base-excitations around the second. third, and fourth natural frequencies are examined in detail. Influences of the fixture mass. gravity. mass centers of mode shapes. and non-linearities are evaluated. Geometrically exact equations governing the planar, harmonic large-amplitude vibrations of beams are solved for operational deflection shapes using the multiple shooting method. Experimental results show the existence of 1:3 and 1:2:3 external and internal resonances. energy transfer from high-frequency modes to the first mode. and amplitude- and phase- modulation among several modes. Moreover, the existence of non-linear normal modes is found to be questionable.

Got Point Clouds: Characterizing Canopy Structure With Active and Passive Sensors

NASA Astrophysics Data System (ADS)

Popescu, S. C.; Malambo, L.; Sheridan, R.; Putman, E.; Murray, S.; Rooney, W.; Rajan, N.

2016-12-01

Unmanned Aerial Systems (UAS) provide the means to acquire highly customized aerial data at local scale with a multitude of sensors. UAS allow us to obtain affordably repeated observations of canopy structure for agricultural and natural resources applications by using passive optical sensors, such as cameras and photogrammetric techniques, and active sensors, such as lidar (Light Detection and Ranging). The objectives of this presentation are to: (1) offer a brief overview of UAS used for agriculture and natural resources studies, (2) describe experiences in conducting agriculture phenotyping and forest vegetation measurements, and (3) give details on the methodology developed for image and lidar data processing for characterizing the three dimensional structure of plant canopies. The UAS types used for this purpose included rotary platforms, such as quadcopters, hexacopters, and octocopters, with a payload capacity of up to 19 lbs. The sensors that collected data over two crop seasons include multispectral cameras in the visible color spectrum and near infrared, and UAS-lidar. For ground reference data we used terrestrial lidar scanners and field measurements. Results comparing UAS and terrestrial measurements show high correlation and open new areas of scientific investigation of crop canopies previously not possible with affordable techniques.

Characterizing monoclonal antibody structure by carbodiimide/GEE footprinting

PubMed Central

Kaur, Parminder; Tomechko, Sara; Kiselar, Janna; Shi, Wuxian; Deperalta, Galahad; Wecksler, Aaron T; Gokulrangan, Giridharan; Ling, Victor; Chance, Mark R

2014-01-01

Amino acid-specific covalent labeling is well suited to probe protein structure and macromolecular interactions, especially for macromolecules and their complexes that are difficult to examine by alternative means, due to size, complexity, or instability. Here we present a detailed account of carbodiimide-based covalent labeling (with GEE tagging) applied to a glycosylated monoclonal antibody therapeutic, which represents an important class of biologic drugs. Characterization of such proteins and their antigen complexes is essential to development of new biologic-based medicines. In this study, the experiments were optimized to preserve the structural integrity of the protein, and experimental conditions were varied and replicated to establish the reproducibility and precision of the technique. Homology-based models were generated and used to compare the solvent accessibility of the labeled residues, which include D, E, and the C-terminus, against the experimental surface accessibility data in order to understand the accuracy of the approach in providing an unbiased assessment of structure. Data from the protein were also compared to reactivity measures of several model peptides to explain sequence or structure-based variations in reactivity. The results highlight several advantages of this approach. These include: the ease of use at the bench top, the linearity of the dose response plots at high levels of labeling (indicating that the label does not significantly perturb the structure of the protein), the high reproducibility of replicate experiments (<2 % variation in modification extent), the similar reactivity of the 3 target probe residues (as suggested by analysis of model peptides), and the overall positive and significant correlation of reactivity and solvent accessible surface area (the latter values predicted by the homology modeling). Attenuation of reactivity, in otherwise solvent accessible probes, is documented as arising from the effects of positive

Characterizing the structure and content of nurse handoffs: A Sequential Conversational Analysis approach.

PubMed

Abraham, Joanna; Kannampallil, Thomas; Brenner, Corinne; Lopez, Karen D; Almoosa, Khalid F; Patel, Bela; Patel, Vimla L

2016-02-01

Effective communication during nurse handoffs is instrumental in ensuring safe and quality patient care. Much of the prior research on nurse handoffs has utilized retrospective methods such as interviews, surveys and questionnaires. While extremely useful, an in-depth understanding of the structure and content of conversations, and the inherent relationships within the content is paramount to designing effective nurse handoff interventions. In this paper, we present a methodological framework-Sequential Conversational Analysis (SCA)-a mixed-method approach that integrates qualitative conversational analysis with quantitative sequential pattern analysis. We describe the SCA approach and provide a detailed example as a proof of concept of its use for the analysis of nurse handoff communication in a medical intensive care unit. This novel approach allows us to characterize the conversational structure, clinical content, disruptions in the conversation, and the inherently phasic nature of nurse handoff communication. The characterization of communication patterns highlights the relationships underlying the verbal content of nurse handoffs with specific emphasis on: the interactive nature of conversation, relevance of role-based (incoming, outgoing) communication requirements, clinical content focus on critical patient-related events, and discussion of pending patient management tasks. We also discuss the applicability of the SCA approach as a method for providing in-depth understanding of the dynamics of communication in other settings and domains. Copyright © 2015 Elsevier Inc. All rights reserved.

Ligand-Assisted Protein Structure (LAPS): An Experimental Paradigm for Characterizing Cannabinoid-Receptor Ligand-Binding Domains.

PubMed

Janero, David R; Korde, Anisha; Makriyannis, Alexandros

2017-01-01

Detailed characterization of the ligand-binding motifs and structure-function correlates of the principal GPCRs of the endocannabinoid-signaling system, the cannabinoid 1 (CB1R) and cannabinoid 2 (CB2R) receptors, is essential to inform the rational design of drugs that modulate CB1R- and CB2R-dependent biosignaling for therapeutic gain. We discuss herein an experimental paradigm termed "ligand-assisted protein structure" (LAPS) that affords a means of characterizing, at the amino acid level, CB1R and CB2R structural features key to ligand engagement and receptor-dependent information transmission. For this purpose, LAPS integrates three key disciplines and methodologies: (a) medicinal chemistry: design and synthesis of high-affinity, pharmacologically active probes as reporters capable of reacting irreversibly with particular amino acids at (or in the immediate vicinity of) the ligand-binding domain of the functionally active receptor; (b) molecular and cellular biology: introduction of discrete, conservative point mutations into the target GPCR and determination of their effect on probe binding and pharmacological activity; (c) analytical chemistry: identification of the site(s) of probe-GPCR interaction through focused, bottom-up, amino acid-level proteomic identification of the probe-receptor complex using liquid chromatography tandem mass spectrometry. Subsequent in silico methods including ligand docking and computational modeling provide supplementary data on the probe-receptor interaction as defined by LAPS. Examples of LAPS as applied to human CB2R orthosteric binding site characterization for a biarylpyrazole antagonist/inverse agonist and a classical cannabinoid agonist belonging to distinct chemical classes of cannabinergic compounds are given as paradigms for further application of this methodology to other therapeutic protein targets. LAPS is well positioned to complement other experimental and in silico methods in contemporary structural biology such

Detailed imaging of flowing structures at depth using microseismicity: a tool for site investigation?

NASA Astrophysics Data System (ADS)

Pytharouli, S.; Lunn, R. J.; Shipton, Z. K.

2011-12-01

Field evidence shows that faults and fractures can act as focused pathways or barriers for fluid migration. This is an important property for modern engineering problems, e.g., CO2 sequestration, geological radioactive waste disposal, geothermal energy exploitation, land reclamation and remediation. For such applications the detailed characterization of the location, orientation and hydraulic properties of existing fractures is necessary. These investigations are expensive, requiring the hire of expensive equipment (excavator or drill rigs), which incur standing charges when not in use. In addition, they only provide information for discrete sample 'windows'. Non-intrusive methods have the ability to gather information across an entire area. Methods including electrical resistivity/conductivity and ground penetrating radar (GRP), have been used as tools for site investigations. Their imaging ability is often restricted due to unfavourable on-site conditions e.g. GRP is not useful in cases where a layer of clay or reinforced concrete is present. Our research has shown that high quality seismic data can be successfully used in the detailed imaging of sub-surface structures at depth; using induced microseismicity data recorded beneath the Açu reservoir in Brazil we identified orientations and values of average permeability of open shear fractures at depths up to 2.5km. Could microseismicity also provide information on the fracture width in terms of stress drops? First results from numerical simulations showed that higher stress drop values correspond to narrower fractures. These results were consistent with geological field observations. This study highlights the great potential of using microseismicity data as a supplementary tool for site investigation. Individual large-scale shear fractures in large rock volumes cannot currently be identified by any other geophysical dataset. The resolution of the method is restricted by the detection threshold of the local

Detailed Multidimensional Simulations of the Structure and Dynamics of Flames

NASA Technical Reports Server (NTRS)

Patnaik, G.; Kailasanath, K.

1999-01-01

Numerical simulations in which the various physical and chemical processes can be independently controlled can significantly advance our understanding of the structure, stability, dynamics and extinction of flames. Therefore, our approach has been to use detailed time-dependent, multidimensional, multispecies numerical models to perform carefully designed computational experiments of flames on Earth and in microgravity environments. Some of these computational experiments are complementary to physical experiments performed under the Microgravity Program while others provide a fundamental understanding that cannot be obtained from physical experiments alone. In this report, we provide a brief summary of our recent research highlighting the contributions since the previous microgravity combustion workshop. There are a number of mechanisms that can cause flame instabilities and result in the formation of dynamic multidimensional structures. In the past, we have used numerical simulations to show that it is the thermo-diffusive instability rather than an instability due to preferential diffusion that is the dominant mechanism for the formation of cellular flames in lean hydrogen-air mixtures. Other studies have explored the role of gravity on flame dynamics and extinguishment, multi-step kinetics and radiative losses on flame instabilities in rich hydrogen-air flames, and heat losses on burner-stabilized flames in microgravity. The recent emphasis of our work has been on exploring flame-vortex interactions and further investigating the structure and dynamics of lean hydrogen-air flames in microgravity. These topics are briefly discussed after a brief discussion of our computational approach for solving these problems.

Structural characterization of toxic oligomers that are kinetically trapped during α-synuclein fibril formation

PubMed Central

Chen, Serene W.; Drakulic, Srdja; Deas, Emma; Ouberai, Myriam; Aprile, Francesco A.; Arranz, Rocío; Ness, Samuel; Roodveldt, Cintia; Guilliams, Tim; De-Genst, Erwin J.; Klenerman, David; Wood, Nicholas W.; Knowles, Tuomas P.J.; Alfonso, Carlos; Rivas, Germán; Abramov, Andrey Y.; Valpuesta, José María; Dobson, Christopher M.; Cremades, Nunilo

2015-01-01

We describe the isolation and detailed structural characterization of stable toxic oligomers of α-synuclein that have accumulated during the process of amyloid formation. Our approach has allowed us to identify distinct subgroups of oligomers and to probe their molecular architectures by using cryo-electron microscopy (cryoEM) image reconstruction techniques. Although the oligomers exist in a range of sizes, with different extents and nature of β-sheet content and exposed hydrophobicity, they all possess a hollow cylindrical architecture with similarities to certain types of amyloid fibril, suggesting that the accumulation of at least some forms of amyloid oligomers is likely to be a consequence of very slow rates of rearrangement of their β-sheet structures. Our findings reveal the inherent multiplicity of the process of protein misfolding and the key role the β-sheet geometry acquired in the early stages of the self-assembly process plays in dictating the kinetic stability and the pathological nature of individual oligomeric species. PMID:25855634

Calculation methods study on hot spot stress of new girder structure detail

NASA Astrophysics Data System (ADS)

Liao, Ping; Zhao, Renda; Jia, Yi; Wei, Xing

2017-10-01

To study modeling calculation methods of new girder structure detail's hot spot stress, based on surface extrapolation method among hot spot stress method, a few finite element analysis models of this welded detail were established by finite element software ANSYS. The influence of element type, mesh density, different local modeling methods of the weld toe and extrapolation methods was analyzed on hot spot stress calculation results at the toe of welds. The results show that the difference of the normal stress in the thickness direction and the surface direction among different models is larger when the distance from the weld toe is smaller. When the distance from the toe is greater than 0.5t, the normal stress of solid models, shell models with welds and non-weld shell models tends to be consistent along the surface direction. Therefore, it is recommended that the extrapolated point should be selected outside the 0.5t for new girder welded detail. According to the results of the calculation and analysis, shell models have good grid stability, and extrapolated hot spot stress of solid models is smaller than that of shell models. So it is suggested that formula 2 and solid45 should be carried out during the hot spot stress extrapolation calculation of this welded detail. For each finite element model under different shell modeling methods, the results calculated by formula 2 are smaller than those of the other two methods, and the results of shell models with welds are the largest. Under the same local mesh density, the extrapolated hot spot stress decreases gradually with the increase of the number of layers in the thickness direction of the main plate, and the variation range is within 7.5%.

Maltose conjugation to PCL: Advanced structural characterization and preliminary biological properties

NASA Astrophysics Data System (ADS)

Secchi, Valeria; Guizzardi, Roberto; Russo, Laura; Pastori, Valentina; Lecchi, Marzia; Franchi, Stefano; Iucci, Giovanna; Battocchio, Chiara; Cipolla, Laura

2018-05-01

The emerging trends in regenerative medicine rely among others on biomaterial-based therapies, with the use of biomaterials as a central delivery system for biochemical and physical cues to manipulate transplanted or ingrowth cells and to orchestrate tissue regeneration. Cell adhesion properties of a biomaterial strongly depend on its surface characteristics. Among others poly(ε-caprolactone) (PCL) is a biocompatible and biodegradable material with low cytotoxicity that is widely adopted as synthetic polymer in several applications. However, it is hydrophobic, which limits its use in tissue engineering. In order to improve its hydrophilicity and cellular compatibility, PCL surface was grafted with maltose through a two-step procedure in which controlled aminolysis of PCL ester bonds by hexanediamine was followed by reductive amination with the carbohydrate reducing end. The modified PCL surface was then characterized in detail by x-ray Photoelectron Spectroscopy (XPS) and Near Edge x-ray Absorption Fine Structure (NEXAFS) spectroscopies. In addition, the biocompatibility of the proposed biomaterial was investigated in preliminary biological assays.

Novel biosynthesis of Ag-hydroxyapatite: Structural and spectroscopic characterization

NASA Astrophysics Data System (ADS)

Ruíz-Baltazar, Álvaro de Jesús; Reyes-López, Simón Yobanny; Silva-Holguin, Pamela Nair; Larrañaga, Daniel; Estévez, Miriam; Pérez, Ramiro

2018-06-01

Silver-doped hydroxyapatite (Ag-HAP) was obtained by green synthesis route. The dopant silver nanoparticles (AgNPs) were obtained by biosynthesis based on Melissa officinalis extract. This research is focused on the characterization and the use of the nontoxic and environment-friendly Ag-HAP nanocomposite. The structural and morphological characterization of Ag-HAP nanocomposite was carried out by scanning electron microscopy (SEM), X-ray diffraction, Fourier-transform infrared (FT-IR) and Raman spectroscopy. The obtained nanoparticles exhibited a great interaction with the HAP matrix, performing an Ag-HAP nanocomposite. Changes in the structure of the Ag-HAP nanocomposite were corroborated by the different characterization techniques. Additionally, a homogeneous distribution of the AgNPs on the HAP structure was observed. The heterogeneous nucleation process employed to doping the HAP, offer a functional route to obtain a green composite with potentials applications in multiple fields, such as tissue engineering, bone repair as well as protein. These properties can be evaluated in subsequent studies.

Structured light imaging system for structural and optical characterization of 3D tissue-simulating phantoms

NASA Astrophysics Data System (ADS)

Liu, Songde; Smith, Zach; Xu, Ronald X.

2016-10-01

There is a pressing need for a phantom standard to calibrate medical optical devices. However, 3D printing of tissue-simulating phantom standard is challenged by lacking of appropriate methods to characterize and reproduce surface topography and optical properties accurately. We have developed a structured light imaging system to characterize surface topography and optical properties (absorption coefficient and reduced scattering coefficient) of 3D tissue-simulating phantoms. The system consisted of a hyperspectral light source, a digital light projector (DLP), a CMOS camera, two polarizers, a rotational stage, a translation stage, a motion controller, and a personal computer. Tissue-simulating phantoms with different structural and optical properties were characterized by the proposed imaging system and validated by a standard integrating sphere system. The experimental results showed that the proposed system was able to achieve pixel-level optical properties with a percentage error of less than 11% for absorption coefficient and less than 7% for reduced scattering coefficient for phantoms without surface curvature. In the meanwhile, 3D topographic profile of the phantom can be effectively reconstructed with an accuracy of less than 1% deviation error. Our study demonstrated that the proposed structured light imaging system has the potential to characterize structural profile and optical properties of 3D tissue-simulating phantoms.

Investigating structural details of lipid-cholesterol-A β interactions

NASA Astrophysics Data System (ADS)

Rai, Durgesh; Anunciado, Divina; Heller, William; O'Neill, Hugh; Urban, Volker; Qian, Shuo

2015-03-01

Alzheimer's disease (AD) is the most common form of dementia and is predicted to affect 1 in 85 people around the world by 2050. Amyloid beta (A β) -peptide, a peptide composed of 40- 42 amino acids that is the product of cleavage from the amyloid precursor protein (APP), is regarded to play a major role in the development of AD. In addition, accumulating evidence points to a positive association between cholesterol and AD. Here, we present results from our studies about A β-peptide and cholesterol in bilayer by small-angle neutron scattering (SANS) using a combination of dimyristoyl, phosphocholine (DMPC) and partially deuterated cholesterol (cholesterol-d7) with and without A β. We compare the results using grazing incidence and transmission SANS on lipid bilayer films and unilamellar vesicles respectively. The structural details on vesicles and bilayers work in conjunction with the circular dichroism on peptide in solution and oriented circular dichroism in bilayer films. The studies confirm a positive association of A β with the membrane layers. The results from different studies will be compared and contrasted in presentation.

Lidar-Based Rock-Fall Hazard Characterization of Cliffs

USGS Publications Warehouse

Collins, Brian D.; Greg M.Stock,

2017-01-01

Rock falls from cliffs and other steep slopes present numerous challenges for detailed geological characterization. In steep terrain, rock-fall source areas are both dangerous and difficult to access, severely limiting the ability to make detailed structural and volumetric measurements necessary for hazard assessment. Airborne and terrestrial lidar survey methods can provide high-resolution data needed for volumetric, structural, and deformation analyses of rock falls, potentially making these analyses straightforward and routine. However, specific methods to collect, process, and analyze lidar data of steep cliffs are needed to maximize analytical accuracy and efficiency. This paper presents observations showing how lidar data sets should be collected, filtered, registered, and georeferenced to tailor their use in rock fall characterization. Additional observations concerning surface model construction, volumetric calculations, and deformation analysis are also provided.

Characterizing monoclonal antibody structure by carboxyl group footprinting

PubMed Central

Kaur, Parminder; Tomechko, Sara E; Kiselar, Janna; Shi, Wuxian; Deperalta, Galahad; Wecksler, Aaron T; Gokulrangan, Giridharan; Ling, Victor; Chance, Mark R

2015-01-01

Structural characterization of proteins and their antigen complexes is essential to the development of new biologic-based medicines. Amino acid-specific covalent labeling (CL) is well suited to probe such structures, especially for cases that are difficult to examine by alternative means due to size, complexity, or instability. We present here a detailed account of carboxyl group labeling (with glycine ethyl ester (GEE) tagging) applied to a glycosylated monoclonal antibody therapeutic (mAb). The experiments were optimized to preserve the structural integrity of the mAb, and experimental conditions were varied and replicated to establish the reproducibility of the technique. Homology-based models were generated and used to compare the solvent accessibility of the labeled residues, which include aspartic acid (D), glutamic acid (E), and the C-terminus (i.e., the target probes), with the experimental data in order to understand the accuracy of the approach. Data from the mAb were compared to reactivity measures of several model peptides to explain observed variations in reactivity. Attenuation of reactivity in otherwise solvent accessible probes is documented as arising from the effects of positive charge or bond formation between adjacent amine and carboxyl groups, the latter accompanied by observed water loss. A comparison of results with previously published data by Deperalta et al using hydroxyl radical footprinting showed that 55% (32/58) of target residues were GEE labeled in this study whereas the previous study reported 21% of the targets were labeled. Although the number of target residues in GEE labeling is fewer, the two approaches provide complementary information. The results highlight advantages of this approach, such as the ease of use at the bench top, the linearity of the dose response plots at high levels of labeling, reproducibility of replicate experiments (<2% variation in modification extent), the similar reactivity of the three target probes

Structural Characterization and Impedance Spectroscopy of Substituted, Fused-Ring Organic Semiconductors

NASA Astrophysics Data System (ADS)

Shaw, Charles Michael

Organic materials present a number of advantages over silicon that make them ideal candidates for modest performance devices like active matrix backplanes and RFID tags. The work detailed here describes both structural characterization of promising new materials, as well as the adaptation of impedance spectroscopy techniques to the study of organic transistors. Unit cells and solution casting behavior for dioctyl- and didodecyl-pentathienoacene are presented. Dioctyl pentathienoacene has an orthorhombic lattice with parameters a = 1.15 nm, b = 0.43 nm and c = 3.05 nm. Didodecyl pentathienoacene has an monoclinic lattice with parameters gamma = 92.2°, a = 1.10 urn, b = 0.42 nm and c = 3.89 nm. Additionally, thermotropic phase behavior is detailed. Both materials exhibit a "side chain melting" transition---characterized by a dramatic unit cell contraction of more than 20%---and smectic C liquid crystal phases. The side chain melting transition shows similarity to phase transitions elicited by exposing these materials to high energy electron flux. In both cases, disorder in the substitutions results in new phases for these materials. Dioctyl-pentathienoacene also exhibits a unique phase, which is intermediately ordered and shows a threefold increase in critical dose over the as-cast phase. Impedance spectroscopy of triisopropylsilyl pentacene transistors suggests these devices are well fit by a Voigt model equivalent circuit. The gate bias dependent resistor represents the channel conductance and the capacitor represents the drain-gate and source-gate capacitances. This in turn suggests that conduction occurs through delocalized states available in ordered regions, with disordered regions contributing localized, immobile states. Impedance spectroscopy of poly(2,5-bis(3-alkylthiophen-2-yl)thieno[3,2-b]thiophene) shows similar behavior. The use of variable temperature impedance spectroscopy is also demonstrated. This technique is used to measure the reduction in trap

Structure of dehaloperoxidase B at 1.58 Å resolution and structural characterization of the AB dimer from Amphitrite ornata

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

Serrano, Vesna de; D’Antonio, Jennifer; Franzen, Stefan

2010-05-01

The crystal structure of dehaloperoxidase (DHP) isoenzyme B from the terebellid polychaete A. ornata, which exhibits both hemoglobin and peroxidase functions, has been determined at 1.58 Å resolution. As members of the globin superfamily, dehaloperoxidase (DHP) isoenzymes A and B from the marine annelid Amphitrite ornata possess hemoglobin function, but they also exhibit a biologically relevant peroxidase activity that is capable of converting 2,4,6-trihalophenols to the corresponding 2,6-dihaloquinones in the presence of hydrogen peroxide. Here, a comprehensive structural study of recombinant DHP B, both by itself and cocrystallized with isoenzyme A, using X-ray diffraction is presented. The structure of DHPmore » B refined to 1.58 Å resolution exhibits the same distal histidine (His55) conformational flexibility as that observed in isoenzyme A, as well as additional changes to the distal and proximal hydrogen-bonding networks. Furthermore, preliminary characterization of the DHP AB heterodimer is presented, which exhibits differences in the AB interface that are not observed in the A-only or B-only homodimers. These structural investigations of DHP B provide insights that may relate to the mechanistic details of the H{sub 2}O{sub 2}-dependent oxidative dehalogenation reaction catalyzed by dehaloperoxidase, present a clearer description of the function of specific residues in DHP at the molecular level and lead to a better understanding of the paradigms of globin structure–function relationships.« less

Structural characterization of thioether-bridged bacteriocins.

PubMed

Lohans, Christopher T; Vederas, John C

2014-01-01

Bacteriocins are a group of ribosomally synthesized antimicrobial peptides produced by bacteria, some of which are extensively post-translationally modified. Some bacteriocins, namely the lantibiotics and sactibiotics, contain one or more thioether bridges. However, these modifications complicate the structural elucidation of these bacteriocins using conventional techniques. This review will discuss the techniques and strategies that have been applied to determine the primary structures of lantibiotics and sactibiotics. A major challenge is to identify the topology of thioether bridges in these peptides (i.e., which amino-acid residues are involved in which bridges). Edman degradation, NMR spectroscopy and tandem MS have all been commonly applied to characterize these bacteriocins, but can be incompatible with the post-translational modifications present. Chemical modifications to the modified residues, such as desulfurization and reduction, make the treated bacteriocins more compatible to analysis by these standard peptide analytical techniques. Despite their differences in structure, similar strategies have proved useful to study the structures of both lantibiotics and sactibiotics.

Detailed Studies on the Structure and Dynamics of Reacting Dusty Flows at Normal and Microgravity

NASA Technical Reports Server (NTRS)

Andac, M. Gurhan; Cracchiola, Brad; Egolfopoulos, Fokion N.; Campbell, Charles S.

1999-01-01

Dusty reacting flows are of particular interest for a wide range of applications. Inert particles can alter the flammability and extinction limits of a combustible mixture. Reacting particles can release substantial amount of heat and can be used either for power generation or propulsion. Accumulation of combustible particles in air can result in explosions which, for example, can occur in grain elevators, during lumber milling and in mine galleries. Furthermore, inert particles are used as flow velocity markers in reacting flows, and their velocity is measured by non-intrusive laser diagnostic techniques. Despite their importance, dusty reacting flows have been less studied and understood compared to gas phase as well as sprays. The addition of solid particles in a flowing gas stream can lead to strong couplings between the two phases, which can be of dynamic, thermal, and chemical nature. The dynamic coupling between the two phases is caused by the inertia that causes the phases to move with different velocities. Furthermore, gravitational, thermophoretic, photophoretic, electrophoretic, diffusiophoretic, centrifugal, and magnetic forces can be exerted on the particles. In general, magnetic, electrophoretic, centrifugal, photophoretic, and diffusiophoretic can be neglected. On the other hand, thermophoretic forces, caused by steep temperature gradients, can be important. The gravitational forces are almost always present and can affect the dynamic response of large particles. Understanding and quantifying the chemical coupling between two phases is a challenging task. However, all reacting particles begin this process as inert particles, and they must be heated before they participate in the combustion process. Thus, one must first understand the interactions of inert particles in a combustion environment. The in-detail understanding of the dynamics and structure of dusty flows can be only advanced by considering simple flow geometries such as the opposed

Noise and current-voltage characterization of complementary heterojunction field-effect transistor (CHFET) structures below 8 K

NASA Technical Reports Server (NTRS)

Cunningham, Thomas J.; Fossum, Eric R.; Baier, Steven M.

1992-01-01

Noise and current-voltage characterization of complementary heterojunction field-effect transistor (CHFET) structures below 8 K are presented. It is shown that the CHFET exhibits normal transistor operation down to 6 K. Some of the details of the transistor operation, such as the gate-voltage dependence of the channel potential, are analyzed. The gate current is examined and is shown to be due to several mechanisms acting in parallel. These include field-emission and thermionic-field-emission, conduction through a temperature-activated resistance, and thermionic emission. The input referred noise for n-channel CHFETs is presented and discussed. The noise has the spectral dependence of 1/f noise, but does not exhibit the usual area dependence.

Characterizing the Secondary Protein Structure of Black Widow Dragline Silk Using Solid-State NMR & X-ray Diffraction

PubMed Central

Jenkins, Janelle E.; Sampath, Sujatha; Butler, Emily; Kim, Jihyun; Henning, Robert W.; Holland, Gregory P.; Yarger, Jeffery L.

2013-01-01

This study provides a detailed secondary structural characterization of major ampullate dragline silk from Latrodectus hesperus (black widow) spiders. X-ray diffraction results show that the structure of black widow major ampullate silk fibers is comprised of stacked β-sheet nanocrystallites oriented parallel to the fiber axis and an amorphous region with oriented (anisotropic) and isotropic components. The combination of two-dimensional (2D) 13C-13C through-space and through-bond solid-state NMR experiments provide chemical shifts that are used to determine detailed information about amino acid motif secondary structure in black widow spider dragline silk. Individual amino acids are incorporated into different repetitive motifs that make up the majority of this protein-based biopolymer. From the solid-state NMR measurements, we assign distinct secondary conformations to each repetitive amino acid motif and hence to the amino acids that make up the motifs. Specifically, alanine is incorporated in β-sheet (poly(Alan) and poly(Gly-Ala)), 31-helix (poly(Gly-Gly-Xaa), and α-helix (poly(Gln-Gln-Ala-Tyr)) components. Glycine is determined to be in β-sheet (poly(Gly-Ala)) and 31-helical (poly(Gly-Gly-Xaa)) regions, while serine is present in β-sheet (poly(Gly-Ala-Ser)), 31-helix (poly(Gly-Gly-Ser)), and β-turn (poly(Gly-Pro-Ser)) structures. These various motif-specific secondary structural elements are quantitatively correlated to the primary amino acid sequence of major ampullate spidroin 1 and 2 (MaSp1 and MaSp2) and are shown to form a self-consistent model for black widow dragline silk. PMID:24024617

Characterization of Structure and Damage in Materials in Four Dimensions

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

Robertson, I. M.; Schuh, C. A.; Vetrano, J. S.

2010-09-30

The materials characterization toolbox has recently experienced a number of parallel revolutionary advances, foreshadowing a time in the near future when materials scientists can quantify material structure across orders of magnitude in length and time scales (i.e., in four dimensions) completely. This paper presents a viewpoint on the materials characterization field, reviewing its recent past, evaluating its present capabilities, and proposing directions for its future development. Electron microscopy; atom-probe tomography; X-ray, neutron and electron tomography; serial sectioning tomography; and diffraction-based analysis methods are reviewed, and opportunities for their future development are highlighted. Particular attention is paid to studies that havemore » pioneered the synergetic use of multiple techniques to provide complementary views of a single structure or process; several of these studies represent the state-of-the-art in characterization, and suggest a trajectory for the continued development of the field. Based on this review, a set of grand challenges for characterization science is identified, including suggestions for instrumentation advances, scientific problems in microstructure analysis, and complex structure evolution problems involving materials damage. The future of microstructural characterization is proposed to be one not only where individual techniques are pushed to their limits, but where the community devises strategies of technique synergy to address complex multiscale problems in materials science and engineering.« less

Fault zone structure and kinematics from lidar, radar, and imagery: revealing new details along the creeping San Andreas Fault

NASA Astrophysics Data System (ADS)

DeLong, S.; Donnellan, A.; Pickering, A.

2017-12-01

Aseismic fault creep, coseismic fault displacement, distributed deformation, and the relative contribution of each have important bearing on infrastructure resilience, risk reduction, and the study of earthquake physics. Furthermore, the impact of interseismic fault creep in rupture propagation scenarios, and its impact and consequently on fault segmentation and maximum earthquake magnitudes, is poorly resolved in current rupture forecast models. The creeping section of the San Andreas Fault (SAF) in Central California is an outstanding area for establishing methodology for future scientific response to damaging earthquakes and for characterizing the fine details of crustal deformation. Here, we describe how data from airborne and terrestrial laser scanning, airborne interferometric radar (UAVSAR), and optical data from satellites and UAVs can be used to characterize rates and map patterns of deformation within fault zones of varying complexity and geomorphic expression. We are evaluating laser point cloud processing, photogrammetric structure from motion, radar interferometry, sub-pixel correlation, and other techniques to characterize the relative ability of each to measure crustal deformation in two and three dimensions through time. We are collecting new and synthesizing existing data from the zone of highest interseismic creep rates along the SAF where a transition from a single main fault trace to a 1-km wide extensional stepover occurs. In the stepover region, creep measurements from alignment arrays 100 meters long across the main fault trace reveal lower rates than those in adjacent, geomorphically simpler parts of the fault. This indicates that deformation is distributed across the en echelon subsidiary faults, by creep and/or stick-slip behavior. Our objectives are to better understand how deformation is partitioned across a fault damage zone, how it is accommodated in the shallow subsurface, and to better characterize the relative amounts of fault creep

Complete structural characterization of ceramides as [M – H]− ions by multiple-stage linear ion trap mass spectrometry

PubMed Central

Hsu, Fong-Fu

2016-01-01

Ceramide is a huge lipid family consisting of diversified structures including various modifications in the fatty acyl chain and the long chain base (LCB). In this contribution, negative-ion ESI linear ion-trap multiple-stage mass spectrometric method (LIT MSn) towards complete structural determination of ceramides in ten major families characterized as the [M – H]− ions is described. Multiple sets of fragment ions reflecting the fatty acyl chain and LCB were observed in the CID MS2 spectrum, while the sequential MS3 and MS4 spectra contain structural information for locating the double bond and the functional groups, permitting realization of the fragmentation processes. Thereby, differentiation of ceramide molecules varied by chain length, the LCB (sphingosine, phytosphigosine, 6-hydroxy-sphingosine), and by the modification (α-hydroxy-, β-hydroxy-, ω-hydroxy-FA) can be achieved; and many isomeric structures in the biological specimen can be revealed in detail. PMID:27523779

Coupling geostatistics to detailed reservoir description allows better visualization and more accurate characterization/simulation of turbidite reservoirs: Elk Hills oil field, California

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

Allan, M.E.; Wilson, M.L.; Wightman, J.

1996-12-31

The Elk Hills giant oilfield, located in the southern San Joaquin Valley of California, has produced 1.1 billion barrels of oil from Miocene and shallow Pliocene reservoirs. 65% of the current 64,000 BOPD production is from the pressure-supported, deeper Miocene turbidite sands. In the turbidite sands of the 31 S structure, large porosity & permeability variations in the Main Body B and Western 31 S sands cause problems with the efficiency of the waterflooding. These variations have now been quantified and visualized using geostatistics. The end result is a more detailed reservoir characterization for simulation. Traditional reservoir descriptions based onmore » marker correlations, cross-sections and mapping do not provide enough detail to capture the short-scale stratigraphic heterogeneity needed for adequate reservoir simulation. These deterministic descriptions are inadequate to tie with production data as the thinly bedded sand/shale sequences blur into a falsely homogenous picture. By studying the variability of the geologic & petrophysical data vertically within each wellbore and spatially from well to well, a geostatistical reservoir description has been developed. It captures the natural variability of the sands and shales that was lacking from earlier work. These geostatistical studies allow the geologic and petrophysical characteristics to be considered in a probabilistic model. The end-product is a reservoir description that captures the variability of the reservoir sequences and can be used as a more realistic starting point for history matching and reservoir simulation.« less

Coupling geostatistics to detailed reservoir description allows better visualization and more accurate characterization/simulation of turbidite reservoirs: Elk Hills oil field, California

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

Allan, M.E.; Wilson, M.L.; Wightman, J.

1996-01-01

The Elk Hills giant oilfield, located in the southern San Joaquin Valley of California, has produced 1.1 billion barrels of oil from Miocene and shallow Pliocene reservoirs. 65% of the current 64,000 BOPD production is from the pressure-supported, deeper Miocene turbidite sands. In the turbidite sands of the 31 S structure, large porosity permeability variations in the Main Body B and Western 31 S sands cause problems with the efficiency of the waterflooding. These variations have now been quantified and visualized using geostatistics. The end result is a more detailed reservoir characterization for simulation. Traditional reservoir descriptions based on markermore » correlations, cross-sections and mapping do not provide enough detail to capture the short-scale stratigraphic heterogeneity needed for adequate reservoir simulation. These deterministic descriptions are inadequate to tie with production data as the thinly bedded sand/shale sequences blur into a falsely homogenous picture. By studying the variability of the geologic petrophysical data vertically within each wellbore and spatially from well to well, a geostatistical reservoir description has been developed. It captures the natural variability of the sands and shales that was lacking from earlier work. These geostatistical studies allow the geologic and petrophysical characteristics to be considered in a probabilistic model. The end-product is a reservoir description that captures the variability of the reservoir sequences and can be used as a more realistic starting point for history matching and reservoir simulation.« less

Nanoscale structural and electronic characterization of α-RuCl3 layered compound

NASA Astrophysics Data System (ADS)

Ziatdinov, Maxim; Maksov, Artem; Banerjee, Arnab; Zhou, Wu; Berlijn, Tom; Yan, Jiaqiang; Nagler, Stephen; Mandrus, David; Baddorf, Arthur; Kalinin, Sergei

The exceptional interplay of spin-orbit effects, Coulomb interaction, and electron-lattice coupling is expected to produce an elaborate phase space of α-RuCl3 layered compound, which to date remains largely unexplored. Here we employ a combination of scanning transmission electron microscopy (STEM) and scanning tunneling microscopy (STM) for detailed evaluation of the system's microscopic structural and electronic orders with a sub-nanometer precision. The STM and STEM measurements are further supported by neutron scattering, X-Ray diffraction, density functional theory (DFT), and multivariate statistical analysis. Our results show a trigonal distortion of Cl octahedral ligand cage along the C3 symmetry axes in each RuCl3 layer. The lattice distortion is limited mainly to the Cl subsystem leaving the Ru honeycomb lattice nearly intact. The STM topographic and spectroscopic characterization reveals an intra unit cell electronic symmetry breaking in a spin-orbit coupled Mott insulating phase on the Cl-terminated surface of α-RuCl3. The associated long-range charge order (CO) pattern is linked to a surface component of Cl cage distortion. We finally discuss a fine structure of CO and its potential relation to variations of average unit cell geometries found in multivariate analysis of STEM data. The research was sponsored by the U.S. Department of Energy.

Devil in the details? Developmental dyslexia and visual long-term memory for details.

PubMed

Huestegge, Lynn; Rohrßen, Julia; van Ermingen-Marbach, Muna; Pape-Neumann, Julia; Heim, Stefan

2014-01-01

Cognitive theories on causes of developmental dyslexia can be divided into language-specific and general accounts. While the former assume that words are special in that associated processing problems are rooted in language-related cognition (e.g., phonology) deficits, the latter propose that dyslexia is rather rooted in a general impairment of cognitive (e.g., visual and/or auditory) processing streams. In the present study, we examined to what extent dyslexia (typically characterized by poor orthographic representations) may be associated with a general deficit in visual long-term memory (LTM) for details. We compared object- and detail-related visual LTM performance (and phonological skills) between dyslexic primary school children and IQ-, age-, and gender-matched controls. The results revealed that while the overall amount of LTM errors was comparable between groups, dyslexic children exhibited a greater portion of detail-related errors. The results suggest that not only phonological, but also general visual resolution deficits in LTM may play an important role in developmental dyslexia.

Detailed Characterization and Profiles of Crankcase and Diesel Particular Matter Exhaust Emissions Using Speciated Organics

PubMed Central

Zielinska, Barbara; Campbell, David; Lawson, Douglas R.; Ireson, Robert G.; Weaver, Christopher S.; Hesterberg, Thomas W.; Larson, Timothy; Davey, Mark; Liu, L.-J. Sally

2008-01-01

A monitoring campaign was conducted in August-September 2005 to compare different experimental approaches quantifying school bus self-pollution. As part of this monitoring campaign, a detailed characterization of PM2.5 diesel engine emissions from the tailpipe and crankcase emissions from the road draft tubes was performed. To distinguish between tailpipe and crankcase vent emissions, a deuterated alkane, n-hexatriacontane-d74 (n-C36D74) was added to the engine oil to serve as intentional quantitative tracers for lubricating oil PM emissions. This paper focuses on the detailed chemical speciation of crankcase and tailpipe PM emissions from two school buses used in this study. We found that organic carbon emission rates were generally higher from the crankcase than from the tailpipe for these two school buses, while elemental carbon contributed significantly only in the tailpipe emissions. The n-C36D74 that was added to the engine oil was emitted at higher rates from the crankcase than the tailpipe. Tracers of engine oil (hopanes, and steranes) were present in much higher proportion in crankcase emissions. Particle-associated PAH emission rates were generally very low (< 1 μg/km), but more PAH species were present in crankcase than in tailpipe emissions. The speciation of samples collected in the bus cabins was consistent with most of the bus self-pollution originating from crankcase emissions. PMID:18754490

Detailed characterization and profiles of crankcase and diesel particulate matter exhaust emissions using speciated organics.

PubMed

Zielinska, Barbara; Campbell, David; Lawson, Douglas R; Ireson, Robert G; Weaver, Christopher S; Hesterberg, Thomas W; Larson, Timothy; Davey, Mark; Liu, L J Sally

2008-08-01

A monitoring campaign was conducted in August-September 2005 to compare different experimental approaches quantifying school bus self-pollution. As part of this monitoring campaign, a detailed characterization of PM2.5 diesel engine emissions from the tailpipe and crankcase emissions from the road draft tubes was performed. To distinguish between tailpipe and crankcase vent emissions, a deuterated alkane, n-hexatriacontane-d74 (n-C36D74) was added to the engine oil to serve as an intentional quantitative tracer for lubricating oil PM emissions. This paper focuses on the detailed chemical speciation of crankcase and tailpipe PM emissions from two school buses used in this study. We found that organic carbon emission rates were generally higher from the crankcase than from the tailpipe for these two school buses, while elemental carbon contributed significantly only in the tailpipe emissions. The n-C36D74 that was added to the engine oil was emitted at higher rates from the crankcase than the tailpipe. Tracers of engine oil (hopanes and steranes) were present in much higher proportion in crankcase emissions. Particle-associated PAH emission rates were generally very low (< 1 microg/km), but more PAH species were present in crankcase than in tailpipe emissions. The speciation of samples collected in the bus cabins was consistent with most of the bus self-pollution originating from crankcase emissions.

Using Multispectral False Color Imaging to Characterize Tropical Cyclone Structure and Environment

NASA Astrophysics Data System (ADS)

Cossuth, J.; Bankert, R.; Richardson, K.; Surratt, M. L.

2016-12-01

The Naval Research Laboratory's (NRL) tropical cyclone (TC) web page (http://www.nrlmry.navy.mil/TC.html) has provided nearly two decades of near real-time access to TC-centric images and products by TC forecasters and enthusiasts around the world. Particularly, microwave imager and sounder information that is featured on this site provides crucial internal storm structure information by allowing users to perceive hydrometeor structure, providing key details beyond cloud top information provided by visible and infrared channels. Towards improving TC analysis techniques and helping advance the utility of the NRL TC webpage resource, new research efforts are presented. This work demonstrates results as well as the methodology used to develop new automated, objective satellite-based TC structure and intensity guidance and enhanced data fusion imagery products that aim to bolster and streamline TC forecast operations. This presentation focuses on the creation and interpretation of false color RGB composite imagery that leverages the different emissive and scattering properties of atmospheric ice, liquid, and vapor water as well as ocean surface roughness as seen by microwave radiometers. Specifically, a combination of near-realtime data and a standardized digital database of global TCs in microwave imagery from 1987-2012 is employed as a climatology of TC structures. The broad range of TC structures, from pinhole eyes through multiple eyewall configurations, is characterized as resolved by passive microwave sensors. The extraction of these characteristic features from historical data also lends itself to statistical analysis. For example, histograms of brightness temperature distributions allows a rigorous examination of how structural features are conveyed in image products, allowing a better representation of colors and breakpoints as they relate to physical features. Such climatological work also suggests steps to better inform the near-real time application of

Structural Characterization of β-Agostic Bonds in Pd-Catalyzed Polymerization

DOE PAGES

Xu, Hongwei; Hu, Chunhua Tony; Wang, Xiaoping; ...

2017-10-23

β-agostic Pd complexes are critical intermediates in catalytic reactions, such as olefin polymerization and Heck reactions. Pd β-agostic complexes, however, have eluded structural characterization, due to the fact that these highly unstable molecules are difficult to isolate. In this paper, we report the single-crystal X-ray and neutron diffraction characterization of β-agostic (α-diimine)Pd–ethyl intermediates in polymerization. Short C α–C β distances and acute Pd–C α–C β bond angles combined serve as unambiguous evidence for the β-agostic interaction. Finally, characterization of the agostic structure and the kinetic barrier for β-H elimination offer important insight into the fundamental understanding of agostic bonds andmore » the mechanism of polymerization.« less

Structural Characterization of β-Agostic Bonds in Pd-Catalyzed Polymerization

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

Xu, Hongwei; Hu, Chunhua Tony; Wang, Xiaoping

β-agostic Pd complexes are critical intermediates in catalytic reactions, such as olefin polymerization and Heck reactions. Pd β-agostic complexes, however, have eluded structural characterization, due to the fact that these highly unstable molecules are difficult to isolate. In this paper, we report the single-crystal X-ray and neutron diffraction characterization of β-agostic (α-diimine)Pd–ethyl intermediates in polymerization. Short C α–C β distances and acute Pd–C α–C β bond angles combined serve as unambiguous evidence for the β-agostic interaction. Finally, characterization of the agostic structure and the kinetic barrier for β-H elimination offer important insight into the fundamental understanding of agostic bonds andmore » the mechanism of polymerization.« less

Structural characterization and numerical simulations of flow properties of standard and reservoir carbonate rocks using micro-tomography

NASA Astrophysics Data System (ADS)

Islam, Amina; Chevalier, Sylvie; Sassi, Mohamed

2018-04-01

With advances in imaging techniques and computational power, Digital Rock Physics (DRP) is becoming an increasingly popular tool to characterize reservoir samples and determine their internal structure and flow properties. In this work, we present the details for imaging, segmentation, as well as numerical simulation of single-phase flow through a standard homogenous Silurian dolomite core plug sample as well as a heterogeneous sample from a carbonate reservoir. We develop a procedure that integrates experimental results into the segmentation step to calibrate the porosity. We also look into using two different numerical tools for the simulation; namely Avizo Fire Xlab Hydro that solves the Stokes' equations via the finite volume method and Palabos that solves the same equations using the Lattice Boltzmann Method. Representative Elementary Volume (REV) and isotropy studies are conducted on the two samples and we show how DRP can be a useful tool to characterize rock properties that are time consuming and costly to obtain experimentally.

Synthesis, characterization and nitrite ion sensing performance of reclaimable composite samples through a core-shell structure

NASA Astrophysics Data System (ADS)

Cui, Xiao; Yuqing, Zhao; Cui, Jiantao; Zheng, Qian; Bo, Wang

2018-02-01

The following paper reported and discussed a nitrite ion optical sensing platform based on a core-shell structure, using superamagnetic nanoparticles as the core, a silica molecular sieve MCM-41 as the shell and two rhodamine derivatives as probe, respectively. This superamagnetic core made this sensing platform reclaimable after finishing nitrite ion sensing procedure. This sensing platform was carefully characterized by means of electron microscopy images, porous structure analysis, magnetic response, IR spectra and thermal stability analysis. Detailed analysis suggested that the emission of these composite samples was quenchable by nitrite ion, showing emission turn off effect. A static sensing mechanism based on an additive reaction between chemosensors and nitrite ion was proposed. These composite samples followed Demas quenching equation against different nitrite ion concentrations. Limit of detection value was obtained as low as 0.4 μM. It was found that, after being quenched by nitrite ion, these composite samples could be reclaimed and recovered by sulphamic acid, confirming their recyclability.

LASER BIOLOGY AND MEDICINE: Visualisation of details of a complicated inner structure of model objects by the method of diffusion optical tomography

NASA Astrophysics Data System (ADS)

Tret'yakov, Evgeniy V.; Shuvalov, Vladimir V.; Shutov, I. V.

2002-11-01

An approximate algorithm is tested for solving the problem of diffusion optical tomography in experiments on the visualisation of details of the inner structure of strongly scattering model objects containing scattering and semitransparent inclusions, as well as absorbing inclusions located inside other optical inhomogeneities. The stability of the algorithm to errors is demonstrated, which allows its use for a rapid (2 — 3 min) image reconstruction of the details of objects with a complicated inner structure.

Harnessing glycomics technologies: integrating structure with function for glycan characterization

PubMed Central

Robinson, Luke N.; Artpradit, Charlermchai; Raman, Rahul; Shriver, Zachary H.; Ruchirawat, Mathuros; Sasisekharan, Ram

2013-01-01

Glycans, or complex carbohydrates, are a ubiquitous class of biological molecules which impinge on a variety of physiological processes ranging from signal transduction to tissue development and microbial pathogenesis. In comparison to DNA and proteins, glycans present unique challenges to the study of their structure and function owing to their complex and heterogeneous structures and the dominant role played by multivalency in their sequence-specific biological interactions. Arising from these challenges, there is a need to integrate information from multiple complementary methods to decode structure-function relationships. Focusing on acidic glycans, we describe here key glycomics technologies for characterizing their structural attributes, including linkage, modifications, and topology, as well as for elucidating their role in biological processes. Two cases studies, one involving sialylated branched glycans and the other sulfated glycosaminoglycans, are used to highlight how integration of orthogonal information from diverse datasets enables rapid convergence of glycan characterization for development of robust structure-function relationships. PMID:22522536

Electromagnetic Characterization Of Metallic Sensory Alloy

NASA Technical Reports Server (NTRS)

Wincheski, Russell A.; Simpson, John; Wallace, Terryl A.; Newman, John A.; Leser, Paul; Lahue, Rob

2012-01-01

Ferromagnetic shape-memory alloy (FSMA) particles undergo changes in both electromagnetic properties and crystallographic structure when strained. When embedded in a structural material, these attributes can provide sensory output of the strain state of the structure. In this work, a detailed characterization of the electromagnetic properties of a FSMA under development for sensory applications is performed. In addition, a new eddy current probe is used to interrogate the electromagnetic properties of individual FSMA particles embedded in the sensory alloy during controlled fatigue tests on the multifunctional material.

Electromagnetic characterization of metallic sensory alloy

NASA Astrophysics Data System (ADS)

Wincheski, Buzz; Simpson, John; Wallace, Terryl; Newman, Andy; Leser, Paul; Lahue, Rob

2013-01-01

Ferromagnetic shape-memory alloy (FSMA) particles undergo changes in both electromagnetic properties and crystallographic structure when strained. When embedded in a structural material, these attributes can provide sensory output of the strain state of the structure. In this work, a detailed characterization of the electromagnetic properties of a FSMA under development for sensory applications is performed. In addition, a new eddy current probe is used to interrogate the electromagnetic properties of individual FSMA particles embedded in the sensory alloy during controlled fatigue tests on the multifunctional material.

Finer parcellation reveals detailed correlational structure of resting-state fMRI signals.

PubMed

Dornas, João V; Braun, Jochen

2018-01-15

Even in resting state, the human brain generates functional signals (fMRI) with complex correlational structure. To simplify this structure, it is common to parcellate a standard brain into coarse chunks. Finer parcellations are considered less reproducible and informative, due to anatomical and functional variability of individual brains. Grouping signals with similar local correlation profiles, restricted to each anatomical region (Tzourio-Mazoyer et al., 2002), we divide a standard brain into 758 'functional clusters' averaging 1.7cm 3 gray matter volume ('MD758' parcellation). We compare 758 'spatial clusters' of similar size ('S758'). 'Functional clusters' are spatially contiguous and cluster quality (integration and segregation of temporal variance) is far superior to 'spatial clusters', comparable to multi-modal parcellations of half the resolution (Craddock et al., 2012; Glasser et al., 2016). Moreover, 'functional clusters' capture many long-range functional correlations, with O(10 5 ) reproducibly correlated cluster pairs in different anatomical regions. The pattern of functional correlations closely mirrors long-range anatomical connectivity established by fibre tracking. MD758 is comparable to coarser parcellations (Craddock et al., 2012; Glasser et al., 2016) in terms of cluster quality, correlational structure (54% relative mutual entropy vs 60% and 61%), and sparseness (35% significant pairwise correlations vs 36% and 44%). We describe and evaluate a simple path to finer functional parcellations of the human brain. Detailed correlational structure is surprisingly consistent between individuals, opening new possibilities for comparing functional correlations between cognitive conditions, states of health, or pharmacological interventions. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Structural, optical and field emission properties of urchin-shaped ZnO nanostructures.

PubMed

Al-Heniti, Saleh; Umar, Ahmad

2013-01-01

In this work, well-crystallized urchin-shaped ZnO structures were synthesized on silicon substrate by simple non-catalytic thermal evaporation process by using metallic zinc powder in the presence of oxygen as source materials for zinc and oxygen, respectively. The synthesized ZnO structures were characterized in detail in terms of their morphological, structural, optical and field emission properties. The detailed morphological investigations revealed that the synthesized structures possess urchin-shape and grown in high-density over the substrate surface. The detailed structural and optical characterizations revealed that the synthesized urchin-shaped ZnO structures are well-crystallized and exhibiting good optical properties. The field emission analysis for urchin-shaped ZnO structures exhibits a turn-on field of 4.6 V/microm. The emission current density reached to 0.056 mA/cm2 at an applied electrical field of 6.4 V/microm and shows no saturation. The calculated field enhancement factor 'beta', from the F-N plot, was found to be approximately 2.2 x 10(3).

Fabrication and Characterizations of Ethanol Sensor Based on CuO Nanoparticles.

PubMed

Al-Hadeethi, Yas; Umar, Ahmad; Kumar, Rajesh; Al-Heniti, Saleh H; Raffah, Bahaaudin M

2018-04-01

In this paper, we report the synthesis, characterization and ethanol sensing applications of CuO nanoparticles. The CuO nanoparticles were prepared by a facile, low-temperature hydrothermal method and characterized in detail in terms of their structural, morphological, compositional and crystalline properties, through different characterization techniques including X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), and Fourier transform infrared (FTIR) spectroscopy. The detailed studies revealed that the synthesized CuO nanoparticles were well-crystalline and possessed monoclinic crystal structure. The synthesized CuO nanoparticles were utilized for the fabrication of highly sensitive ethanol gas sensor. At an optimized temperature of 320 °C, high sensitivity (Ra/Rg) of 39.29 was observed for 200 ppm of ethanol gas. Additionally, very low response (τres = 14 s) and recovery (τrec = 30 s) times were observed for 100 ppm of ethanol.

Molecular details of the yeast frataxin-Isu1 interaction during mitochondrial Fe-S cluster assembly

PubMed Central

Cook, Jeremy D.; Kondapalli, Kalyan C.; Rawat, Swati; Childs, William C.; Murugesan, Yogapriya; Dancis, Andrew; Stemmler, Timothy L.

2010-01-01

Frataxin, a conserved nuclear encoded mitochondrial protein, plays a direct role in iron-sulfur cluster biosynthesis within the ISC assembly pathway. Humans with frataxin deficiency have Friedreich’s ataxia, a neurodegenerative disorder characterized by mitochondrial iron overload and disruption in Fe-S cluster synthesis. Biochemical and genetic studies have shown frataxin interacts with the iron-sulfur cluster assembly scaffold protein (in yeast, there are two: Isu1 and Isu2), indicating frataxin plays a direct role in cluster assembly, possibly by serving as an iron chaperone n the assembly pathway. Here we provide molecular details of how yeast frataxin (Yfh1) interacts with Isu1 as a structural module to better understand the multiprotein complex assembly that completes Fe-S cluster assembly; this complex also includes the cysteine desulfurase (Nfs1 in yeast) and the accessory protein (Isd11), together in the mitochondria. Thermodynamic binding parameters for protein partner and iron binding were measured for the yeast orthologs using isothermal titration calorimetry (ITC). Nuclear magnetic resonance spectroscopy was used to provide the molecular details to understand how Yfh1 interacts with Isu1. X-ray absorption studies were used to electronically and structurally characterize how iron is transferred to Isu1 and then incorporated into a Fe-S cluster. These results were combined with previously published data to generate a structural model for how the Fe-S cluster protein assembly complex can come together to accomplish Fe-S cluster assembly. PMID:20815377

Molecular Details of the Yeast Frataxin-Isu1 Interaction during Mitochondrial Fe-S Cluster Assembly

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

Cook, J.; Kondapalli, K; Rawat, S

2010-01-01

Frataxin, a conserved nuclear-encoded mitochondrial protein, plays a direct role in iron-sulfur cluster biosynthesis within the ISC assembly pathway. Humans with frataxin deficiency have Friedreich's ataxia, a neurodegenerative disorder characterized by mitochondrial iron overload and disruption in Fe-S cluster synthesis. Biochemical and genetic studies have shown frataxin interacts with the iron-sulfur cluster assembly scaffold protein (in yeast, there are two, Isu1 and Isu2), indicating frataxin plays a direct role in cluster assembly, possibly by serving as an iron chaperone in the assembly pathway. Here we provide molecular details of how yeast frataxin (Yfh1) interacts with Isu1 as a structural modulemore » to improve our understanding of the multiprotein complex assembly that completes Fe-S cluster assembly; this complex also includes the cysteine desulfurase (Nfs1 in yeast) and the accessory protein (Isd11), together in the mitochondria. Thermodynamic binding parameters for protein partner and iron binding were measured for the yeast orthologs using isothermal titration calorimetry. Nuclear magnetic resonance spectroscopy was used to provide the molecular details to understand how Yfh1 interacts with Isu1. X-ray absorption studies were used to electronically and structurally characterize how iron is transferred to Isu1 and then incorporated into an Fe-S cluster. These results were combined with previously published data to generate a structural model for how the Fe-S cluster protein assembly complex can come together to accomplish Fe-S cluster assembly.« less

Molecular details of the yeast frataxin-Isu1 interaction during mitochondrial Fe-S cluster assembly.

PubMed

Cook, Jeremy D; Kondapalli, Kalyan C; Rawat, Swati; Childs, William C; Murugesan, Yogapriya; Dancis, Andrew; Stemmler, Timothy L

2010-10-12

Frataxin, a conserved nuclear-encoded mitochondrial protein, plays a direct role in iron-sulfur cluster biosynthesis within the ISC assembly pathway. Humans with frataxin deficiency have Friedreich's ataxia, a neurodegenerative disorder characterized by mitochondrial iron overload and disruption in Fe-S cluster synthesis. Biochemical and genetic studies have shown frataxin interacts with the iron-sulfur cluster assembly scaffold protein (in yeast, there are two, Isu1 and Isu2), indicating frataxin plays a direct role in cluster assembly, possibly by serving as an iron chaperone in the assembly pathway. Here we provide molecular details of how yeast frataxin (Yfh1) interacts with Isu1 as a structural module to improve our understanding of the multiprotein complex assembly that completes Fe-S cluster assembly; this complex also includes the cysteine desulfurase (Nfs1 in yeast) and the accessory protein (Isd11), together in the mitochondria. Thermodynamic binding parameters for protein partner and iron binding were measured for the yeast orthologs using isothermal titration calorimetry. Nuclear magnetic resonance spectroscopy was used to provide the molecular details to understand how Yfh1 interacts with Isu1. X-ray absorption studies were used to electronically and structurally characterize how iron is transferred to Isu1 and then incorporated into an Fe-S cluster. These results were combined with previously published data to generate a structural model for how the Fe-S cluster protein assembly complex can come together to accomplish Fe-S cluster assembly.

Characterization of technical surfaces by structure function analysis

NASA Astrophysics Data System (ADS)

Kalms, Michael; Kreis, Thomas; Bergmann, Ralf B.

2018-03-01

The structure function is a tool for characterizing technical surfaces that exhibits a number of advantages over Fourierbased analysis methods. So it is optimally suited for analyzing the height distributions of surfaces measured by full-field non-contacting methods. The structure function is thus a useful method to extract global or local criteria like e. g. periodicities, waviness, lay, or roughness to analyze and evaluate technical surfaces. After the definition of line- and area-structure function and offering effective procedures for their calculation this paper presents examples using simulated and measured data of technical surfaces including aircraft parts.

White Light Used to Enable Enhanced Surface Topography, Geometry, and Wear Characterization of Oil-Free Bearings

NASA Technical Reports Server (NTRS)

Lucero, John M.

2003-01-01

A new optically based measuring capability that characterizes surface topography, geometry, and wear has been employed by NASA Glenn Research Center s Tribology and Surface Science Branch. To characterize complex parts in more detail, we are using a three-dimensional, surface structure analyzer-the NewView5000 manufactured by Zygo Corporation (Middlefield, CT). This system provides graphical images and high-resolution numerical analyses to accurately characterize surfaces. Because of the inherent complexity of the various analyzed assemblies, the machine has been pushed to its limits. For example, special hardware fixtures and measuring techniques were developed to characterize Oil- Free thrust bearings specifically. We performed a more detailed wear analysis using scanning white light interferometry to image and measure the bearing structure and topography, enabling a further understanding of bearing failure causes.

Energetics and Structural Characterization of the large-scale Functional Motion of Adenylate Kinase

PubMed Central

Formoso, Elena; Limongelli, Vittorio; Parrinello, Michele

2015-01-01

Adenylate Kinase (AK) is a signal transducing protein that regulates cellular energy homeostasis balancing between different conformations. An alteration of its activity can lead to severe pathologies such as heart failure, cancer and neurodegenerative diseases. A comprehensive elucidation of the large-scale conformational motions that rule the functional mechanism of this enzyme is of great value to guide rationally the development of new medications. Here using a metadynamics-based computational protocol we elucidate the thermodynamics and structural properties underlying the AK functional transitions. The free energy estimation of the conformational motions of the enzyme allows characterizing the sequence of events that regulate its action. We reveal the atomistic details of the most relevant enzyme states, identifying residues such as Arg119 and Lys13, which play a key role during the conformational transitions and represent druggable spots to design enzyme inhibitors. Our study offers tools that open new areas of investigation on large-scale motion in proteins. PMID:25672826

Energetics and Structural Characterization of the large-scale Functional Motion of Adenylate Kinase

NASA Astrophysics Data System (ADS)

Formoso, Elena; Limongelli, Vittorio; Parrinello, Michele

2015-02-01

Adenylate Kinase (AK) is a signal transducing protein that regulates cellular energy homeostasis balancing between different conformations. An alteration of its activity can lead to severe pathologies such as heart failure, cancer and neurodegenerative diseases. A comprehensive elucidation of the large-scale conformational motions that rule the functional mechanism of this enzyme is of great value to guide rationally the development of new medications. Here using a metadynamics-based computational protocol we elucidate the thermodynamics and structural properties underlying the AK functional transitions. The free energy estimation of the conformational motions of the enzyme allows characterizing the sequence of events that regulate its action. We reveal the atomistic details of the most relevant enzyme states, identifying residues such as Arg119 and Lys13, which play a key role during the conformational transitions and represent druggable spots to design enzyme inhibitors. Our study offers tools that open new areas of investigation on large-scale motion in proteins.

10. DETAIL, CAB SIDE. DETAIL, END OF BOOM. DETAIL, LOWER ...

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

10. DETAIL, CAB SIDE. DETAIL, END OF BOOM. DETAIL, LOWER PART OF TOWER, SHOWING METAL WHEELS AND CABLE SPOOLS. DETAIL, LOOKING UP AT THE UNDERSIDE OF THE REVOLVING PLATFORM ATOP THE TOWER. - United Engineering Company Shipyard, Crane, 2900 Main Street, Alameda, Alameda County, CA

Detailed Physiologic Characterization Reveals Diverse Mechanisms for Novel Genetic Loci Regulating Glucose and Insulin Metabolism in Humans

PubMed Central

Ingelsson, Erik; Langenberg, Claudia; Hivert, Marie-France; Prokopenko, Inga; Lyssenko, Valeriya; Dupuis, Josée; Mägi, Reedik; Sharp, Stephen; Jackson, Anne U.; Assimes, Themistocles L.; Shrader, Peter; Knowles, Joshua W.; Zethelius, Björn; Abbasi, Fahim A.; Bergman, Richard N.; Bergmann, Antje; Berne, Christian; Boehnke, Michael; Bonnycastle, Lori L.; Bornstein, Stefan R.; Buchanan, Thomas A.; Bumpstead, Suzannah J.; Böttcher, Yvonne; Chines, Peter; Collins, Francis S.; Cooper, Cyrus C.; Dennison, Elaine M.; Erdos, Michael R.; Ferrannini, Ele; Fox, Caroline S.; Graessler, Jürgen; Hao, Ke; Isomaa, Bo; Jameson, Karen A.; Kovacs, Peter; Kuusisto, Johanna; Laakso, Markku; Ladenvall, Claes; Mohlke, Karen L.; Morken, Mario A.; Narisu, Narisu; Nathan, David M.; Pascoe, Laura; Payne, Felicity; Petrie, John R.; Sayer, Avan A.; Schwarz, Peter E. H.; Scott, Laura J.; Stringham, Heather M.; Stumvoll, Michael; Swift, Amy J.; Syvänen, Ann-Christine; Tuomi, Tiinamaija; Tuomilehto, Jaakko; Tönjes, Anke; Valle, Timo T.; Williams, Gordon H.; Lind, Lars; Barroso, Inês; Quertermous, Thomas; Walker, Mark; Wareham, Nicholas J.; Meigs, James B.; McCarthy, Mark I.; Groop, Leif; Watanabe, Richard M.; Florez, Jose C.

2010-01-01

OBJECTIVE Recent genome-wide association studies have revealed loci associated with glucose and insulin-related traits. We aimed to characterize 19 such loci using detailed measures of insulin processing, secretion, and sensitivity to help elucidate their role in regulation of glucose control, insulin secretion and/or action. RESEARCH DESIGN AND METHODS We investigated associations of loci identified by the Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) with circulating proinsulin, measures of insulin secretion and sensitivity from oral glucose tolerance tests (OGTTs), euglycemic clamps, insulin suppression tests, or frequently sampled intravenous glucose tolerance tests in nondiabetic humans (n = 29,084). RESULTS The glucose-raising allele in MADD was associated with abnormal insulin processing (a dramatic effect on higher proinsulin levels, but no association with insulinogenic index) at extremely persuasive levels of statistical significance (P = 2.1 × 10−71). Defects in insulin processing and insulin secretion were seen in glucose-raising allele carriers at TCF7L2, SCL30A8, GIPR, and C2CD4B. Abnormalities in early insulin secretion were suggested in glucose-raising allele carriers at MTNR1B, GCK, FADS1, DGKB, and PROX1 (lower insulinogenic index; no association with proinsulin or insulin sensitivity). Two loci previously associated with fasting insulin (GCKR and IGF1) were associated with OGTT-derived insulin sensitivity indices in a consistent direction. CONCLUSIONS Genetic loci identified through their effect on hyperglycemia and/or hyperinsulinemia demonstrate considerable heterogeneity in associations with measures of insulin processing, secretion, and sensitivity. Our findings emphasize the importance of detailed physiological characterization of such loci for improved understanding of pathways associated with alterations in glucose homeostasis and eventually type 2 diabetes. PMID:20185807

The characterization of widespread fatigue damage in fuselage structure

NASA Technical Reports Server (NTRS)

Piascik, Robert S.; Willard, Scott A.; Miller, Matthew

1994-01-01

The characteristics of widespread fatigue damage (WSFD) in fuselage riveted structure were established by detailed nondestructive and destructive examinations of fatigue damage contained in a full size fuselage test article. The objectives of this were to establish an experimental data base for validating emerging WSFD analytical prediction methodology and to identify first order effects that contribute to fatigue crack initiation and growth. Detailed examinations were performed on a test panel containing four bays of a riveted lap splice joint. The panel was removed from a full scale fuselage test article after receiving 60,000 full pressurization cycles. The results of in situ examinations document the progression of fuselage skin fatigue crack growth through crack linkup. Detailed tear down examinations and fractography of the lap splice joint region revealed fatigue crack initiation sites, crack morphology, and crack linkup geometry. From this large data base, distributions of crack size and locations are presented and discussions of operative damage mechanisms are offered.

The characterization of widespread fatigue damage in fuselage structure

NASA Technical Reports Server (NTRS)

Piascik, Robert S.; Willard, Scott A.; Miller, Matthew

1994-01-01

The characteristics of widespread fatigue damage (WSFD) in fuselage riveted structure were established by detailed nondestructive and destructive examinations of fatigue damage contained in a full size fuselage test article. The objectives of this work were to establish an experimental data base for validating emerging WSFD analytical prediction methodology and to identify first order effects that contribute to fatigue crack initiation and growth. Detailed examinations were performed on a test panel containing four bays of a riveted lap splice joint. The panel was removed from a full scale fuselage test article after receiving 60,000 full pressurization cycles. The results of in situ examinations document the progression of fuselage skin fatigue crack growth through crack linkup. Detailed tear down examinations and fractography of the lap splice joint region revealed fatigue crack initiation sites, crack morphology and crack linkup geometry. From this large data base, distributions of crack size and locations are presented and discussions of operative damage mechanisms are offered.

Detailed characterization of a long-term rodent model of critical illness and recovery.

PubMed

Hill, Neil E; Saeed, Saima; Phadke, Rahul; Ellis, Matthew J; Chambers, Darren; Wilson, Duncan R; Castells, Josiane; Morel, Jerome; Freysennet, Damien G; Brett, Stephen J; Murphy, Kevin G; Singer, Mervyn

2015-03-01

To characterize a long-term model of recovery from critical illness, with particular emphasis on cardiorespiratory, metabolic, and muscle function. Randomized controlled animal study. University research laboratory. Male Wistar rats. Intraperitoneal injection of the fungal cell wall constituent, zymosan or n-saline. Following intervention, rats were followed for up to 2 weeks. Animals with zymosan peritonitis reached a clinical and biochemical nadir on day 2. Initial reductions were seen in body weight, total body protein and fat, and muscle mass. Leg muscle fiber diameter remained subnormal at 14 days with evidence of persisting myonecrosis, even though gene expression of regulators of muscle mass (e.g., MAFbx, MURF1, and myostatin) had peaked on days 2-4 but normalized by day 7. Treadmill exercise capacity, forelimb grip strength, and in vivo maximum tetanic force were also reduced. Food intake was minimal until day 4 but increased thereafter. This did not relate to appetite hormone levels with early (6 hr) rises in plasma insulin and leptin followed by persisting subnormal levels; ghrelin levels did not change. Serum interleukin-6 level peaked at 6 hours but had normalized by day 2, whereas interleukin-10 remained persistently elevated and high-density lipoprotein cholesterol persistently depressed. There was an early myocardial depression and rise in core temperature, yet reduced oxygen consumption and respiratory exchange ratio with a loss of diurnal rhythmicity that showed a gradual but incomplete recovery by day 7. This detailed physiological, metabolic, hormonal, functional, and histological muscle characterization of a model of critical illness and recovery reproduces many of the findings reported in human critical illness. It can be used to assess putative therapies that may attenuate loss, or enhance recovery, of muscle mass and function.

Characterization of Nanophase Materials

NASA Astrophysics Data System (ADS)

Wang, Zhong Lin

2000-01-01

Engineering of nanophase materials and devices is of vital interest in electronics, semiconductors and optics, catalysis, ceramics and magnetism. Research associated with nanoparticles has widely spread and diffused into every field of scientific research, forming a trend of nanocrystal engineered materials. The unique properties of nanophase materials are entirely determined by their atomic scale structures, particularly the structures of interfaces and surfaces. Development of nanotechnology involves several steps, of which characterization of nanoparticles is indespensable to understand the behavior and properties of nanoparticles, aiming at implementing nanotechnolgy, controlling their behavior and designing new nanomaterials systems with super performance. The book will focus on structural and property characterization of nanocrystals and their assemblies, with an emphasis on basic physical approach, detailed techniques, data interpretation and applications. Intended readers of this comprehensive reference work are advanced graduate students and researchers in the field, who are specialized in materials chemistry, materials physics and materials science.

Advances in Chemical and Structural Characterization of Concretion with Implications for Modeling Marine Corrosion

NASA Astrophysics Data System (ADS)

Johnson, Donald L.; DeAngelis, Robert J.; Medlin, Dana J.; Carr, James D.; Conlin, David L.

2014-05-01

The Weins number model and concretion equivalent corrosion rate methodology were developed as potential minimum-impact, cost-effective techniques to determine corrosion damage on submerged steel structures. To apply the full potential of these technologies, a detailed chemical and structural characterization of the concretion (hard biofouling) that transforms into iron bearing minerals is required. The fractions of existing compounds and the quantitative chemistries are difficult to determine from x-ray diffraction. Environmental scanning electron microscopy was used to present chemical compositions by means of energy-dispersive spectroscopy (EDS). EDS demonstrates the chemical data in mapping format or in point or selected area chemistries. Selected-area EDS data collection at precise locations is presented in terms of atomic percent. The mechanism of formation and distribution of the iron-bearing mineral species at specific locations will be presented. Based on water retention measurements, porosity in terms of void volume varies from 15 v/o to 30 v/o (vol.%). The void path displayed by scanning electron microscopy imaging illustrates the tortuous path by which oxygen migrates in the water phase within the concretion from seaside to metalside.

Sizing Single Cantilever Beam Specimens for Characterizing Facesheet/Core Peel Debonding in Sandwich Structure

NASA Technical Reports Server (NTRS)

Ratcliffe, James G.

2010-01-01

This paper details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. The specific test method selected for the standardized test procedure utilizes a single cantilever beam (SCB) specimen configuration. The objective of the current work is to develop a method for establishing SCB specimen dimensions. This is achieved by imposing specific limitations on specimen dimensions, with the objectives of promoting a linear elastic specimen response, and simplifying the data reduction method required for computing the critical strain energy release rate associated with debonding. The sizing method is also designed to be suitable for incorporation into a standardized test protocol. Preliminary application of the resulting sizing method yields practical specimen dimensions.

Detailed characterization of the LLNL imaging proton spectrometer

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

Rasmus, A. M., E-mail: rasmus@lanl.gov, E-mail: arasmus@umich.edu; University of Michigan, Ann Arbor, Michigan 48109; Hazi, A. U.

2016-11-15

Ultra-intense short pulse lasers incident on solid targets (e.g., thin Au foils) produce well collimated, broad-spectrum proton beams. These proton beams can be used to characterize magnetic fields, electric fields, and density gradients in high energy-density systems. The LLNL-Imaging Proton Spectrometer (L-IPS) was designed and built [H. Chen et al., Rev. Sci. Instrum. 81, 10D314 (2010)] for use with such laser produced proton beams. The L-IPS has an energy range of 50 keV-40 MeV with a resolving power (E/dE) of about 275 at 1 MeV and 21 at 20 MeV, as well as a single spatial imaging axis. In ordermore » to better characterize the dispersion and imaging capability of this diagnostic, a 3D finite element analysis solver is used to calculate the magnetic field of the L-IPS. Particle trajectories are then obtained via numerical integration to determine the dispersion relation of the L-IPS in both energy and angular space.« less

An integrated approach using orthogonal analytical techniques to characterize heparan sulfate structure.

PubMed

Beccati, Daniela; Lech, Miroslaw; Ozug, Jennifer; Gunay, Nur Sibel; Wang, Jing; Sun, Elaine Y; Pradines, Joël R; Farutin, Victor; Shriver, Zachary; Kaundinya, Ganesh V; Capila, Ishan

2017-02-01

Heparan sulfate (HS), a glycosaminoglycan present on the surface of cells, has been postulated to have important roles in driving both normal and pathological physiologies. The chemical structure and sulfation pattern (domain structure) of HS is believed to determine its biological function, to vary across tissue types, and to be modified in the context of disease. Characterization of HS requires isolation and purification of cell surface HS as a complex mixture. This process may introduce additional chemical modification of the native residues. In this study, we describe an approach towards thorough characterization of bovine kidney heparan sulfate (BKHS) that utilizes a variety of orthogonal analytical techniques (e.g. NMR, IP-RPHPLC, LC-MS). These techniques are applied to characterize this mixture at various levels including composition, fragment level, and overall chain properties. The combination of these techniques in many instances provides orthogonal views into the fine structure of HS, and in other instances provides overlapping / confirmatory information from different perspectives. Specifically, this approach enables quantitative determination of natural and modified saccharide residues in the HS chains, and identifies unusual structures. Analysis of partially digested HS chains allows for a better understanding of the domain structures within this mixture, and yields specific insights into the non-reducing end and reducing end structures of the chains. This approach outlines a useful framework that can be applied to elucidate HS structure and thereby provides means to advance understanding of its biological role and potential involvement in disease progression. In addition, the techniques described here can be applied to characterization of heparin from different sources.

Invited review article: Photopyroelectric calorimeter for the simultaneous thermal, optical, and structural characterization of samples over phase transitions.

PubMed

Zammit, U; Marinelli, M; Mercuri, F; Paoloni, S; Scudieri, F

2011-12-01

The study of thermophysical properties is of great importance in several scientific fields. Among them, the heat capacity, for example, is related to the microscopic structure of condensed matter and plays an important role in monitoring the changes in the energy content of a system. Calorimetric techniques are thus of fundamental importance for characterizing physical systems, particularly in the vicinity of phase transitions where energy fluctuations can play an important role. In this work, the ability of the Photopyroelctric calorimetry to study the versus temperature behaviour of the specific heat and of the other thermal parameters in the vicinity of phase transitions is outlined. The working principle, the theoretical basis, the experimental configurations, and the advantages of this technique, with respect to the more conventional ones, have been described and discussed in detail. The integrations in the calorimetric setup giving the possibility to perform, simultaneously with the calorimetric studies, complementary kind of characterizations of optical, structural, and electrical properties are also described. A review of the results obtained with this technique, in all its possible configurations, for the high temperature resolution studies of the thermal parameters over several kinds of phase transitions occurring in different systems is presented and discussed.

Synthesis and structural characterization of the hexagonal anti-perovskite Na{sub 2}CaVO{sub 4}F

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

Green, Robert L., E-mail: rgreen@flpoly.org; Avdeev, Maxim; School of Chemistry, The University of Sydney, Sydney, NSW 2006

The structural details of the ordered hexagonal oxyfluoride Na{sub 2}CaVO{sub 4}F prepared by solid-state synthesis using stoichiometric amounts of V{sub 2}O{sub 5}, CaCO{sub 3}, Na{sub 2}CO{sub 3} and NaF were characterized using high-resolution neutron powder diffraction. The structural changes between 25 °C and 750 °C revealed that the two structural subunits in this material behave different when heated: there is an expansion of the face-shared FNa{sub 4}Ca{sub 2} octahedra while the VO{sub 4} tetrahedra due to increased thermal disorder reveal marginal bond contractions. Bond valences and the global instability index point to significant structural disorder at 750 °C. - Graphicalmore » abstract: The structure of the novel oxyfluoride Na{sub 2}CaVO{sub 4}F is studied at room temperature and high-temperatures. The structure can be viewed as layers of compression and elongation of polyhedral subunits, which change as a function of temperature. - Highlights: • The novel oxyfluoride, Na{sub 2}CaVO{sub 4}F, is synthesized via solid-state method. • High-resolution neutron diffraction data is used to analyze the structure of Na{sub 2}CaVO{sub 4}F. • Structural subunits exhibit expansion and contraction with increasing temperature. • Higher temperatures increase instability within the structure of Na{sub 2}CaVO{sub 4}F.« less

Characterization of turbulent coherent structures in square duct flow

NASA Astrophysics Data System (ADS)

Atzori, Marco; Vinuesa, Ricardo; Lozano-Durán, Adrián; Schlatter, Philipp

2018-04-01

This work is aimed at a first characterization of coherent structures in turbulent square duct flows. Coherent structures are defined as connected components in the domain identified as places where a quantity of interest (such as Reynolds stress or vorticity) is larger than a prescribed non-uniform threshold. Firstly, we qualitatively discuss how a percolation analysis can be used to assess the effectiveness of the threshold function, and how it can be affected by statistical uncertainty. Secondly, various physical quantities that are expected to play an important role in the dynamics of the secondary flow of Prandtl’s second kind are studied. Furthermore, a characterization of intense Reynolds-stress events in square duct flow, together with a comparison of their shape for analogous events in channel flow at the same Reynolds number, is presented.

Structural characterization of magnesium silicate hydrate: towards the design of eco-sustainable cements.

PubMed

Tonelli, M; Martini, F; Calucci, L; Fratini, E; Geppi, M; Ridi, F; Borsacchi, S; Baglioni, P

2016-02-28

Magnesium-based cement is one of the most interesting eco-sustainable alternatives to standard cementitious binders. The reasons for the interest towards this material are twofold: (i) its production process, using magnesium silicates, brine or seawater, dramatically reduces CO2 emissions with respect to Portland cement production, and (ii) it is very well suited to applications in radioactive waste encapsulation. In spite of its potential, assessment of the structural properties of its binder phase (magnesium silicate hydrate or M-S-H) is far from complete, especially because of its amorphous character. In this work, a comprehensive structural characterization of M-S-H was obtained using a multi-technique approach, including a detailed solid-state NMR investigation and, in particular, for the first time, quantitative (29)Si solid-state NMR data. M-S-H was prepared through room-temperature hydration of highly reactive MgO and silica fume and was monitored for 28 days. The results clearly evidenced the presence in M-S-H of "chrysotile-like" and "talc-like" sub-nanometric domains, which are approximately in a 1 : 1 molar ratio after long-time hydration. Both these kinds of domains have a high degree of condensation, corresponding to the presence of a small amount of silanols in the tetrahedral sheets. The decisive improvement obtained in the knowledge of M-S-H structure paves the way for tailoring the macroscopic properties of eco-sustainable cements by means of a bottom-up approach.

Femtosecond Pulse Characterization as Applied to One-Dimensional Photonic Band Edge Structures

NASA Technical Reports Server (NTRS)

Fork, Richard L.; Gamble, Lisa J.; Diffey, William M.

1999-01-01

The ability to control the group velocity and phase of an optical pulse is important to many current active areas of research. Electronically addressable one-dimensional photonic crystals are an attractive candidate to achieve this control. This report details work done toward the characterization of photonic crystals and improvement of the characterization technique. As part of the work, the spectral dependence of the group delay imparted by a GaAs/AlAs photonic crystal was characterized. Also, a first generation an electrically addressable photonic crystal was tested for the ability to electronically control the group delay. The measurement technique, using 100 femtosecond continuum pulses was improved to yield high spectral resolution (1.7 nanometers) and concurrently with high temporal resolution (tens of femtoseconds). Conclusions and recommendations based upon the work done are also presented.

Detailed characterizations of a Comparative Reactivity Method (CRM) instrument: experiments vs. modelling

NASA Astrophysics Data System (ADS)

Michoud, V.; Hansen, R. F.; Locoge, N.; Stevens, P. S.; Dusanter, S.

2015-04-01

The Hydroxyl radical (OH) is an important oxidant in the daytime troposphere that controls the lifetime of most trace gases, whose oxidation leads to the formation of harmful secondary pollutants such as ozone (O3) and Secondary Organic Aerosols (SOA). In spite of the importance of OH, uncertainties remain concerning its atmospheric budget and integrated measurements of the total sink of OH can help reducing these uncertainties. In this context, several methods have been developed to measure the first-order loss rate of ambient OH, called total OH reactivity. Among these techniques, the Comparative Reactivity Method (CRM) is promising and has already been widely used in the field and in atmospheric simulation chambers. This technique relies on monitoring competitive OH reactions between a reference molecule (pyrrole) and compounds present in ambient air inside a sampling reactor. However, artefacts and interferences exist for this method and a thorough characterization of the CRM technique is needed. In this study, we present a detailed characterization of a CRM instrument, assessing the corrections that need to be applied on ambient measurements. The main corrections are, in the order of their integration in the data processing: (1) a correction for a change in relative humidity between zero air and ambient air, (2) a correction for the formation of spurious OH when artificially produced HO2 react with NO in the sampling reactor, and (3) a correction for a deviation from pseudo first-order kinetics. The dependences of these artefacts to various measurable parameters, such as the pyrrole-to-OH ratio or the bimolecular reaction rate constants of ambient trace gases with OH are also studied. From these dependences, parameterizations are proposed to correct the OH reactivity measurements from the abovementioned artefacts. A comparison of experimental and simulation results is then discussed. The simulations were performed using a 0-D box model including either (1) a

Synthesis and structural characterization of CZTS nanoparticles

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

Lydia, R.; Reddy, P. Sreedhara

2013-06-03

The CZTS nanoparticles were successfully synthesized by Chemical co-precipitation method with different pH values in the range of 6 to 8. The synthesized nanoparticles were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. XRD studies revealed that the CZTS nanoparticles exhibited Kesterite Structure with preferential orientation along the (112) direction. Sample at pH value of 7 reached the nearly stoichiometric ratio.

Comparison of detailed and reduced kinetics mechanisms of silane oxidation in the basis of detonation wave structure problem

NASA Astrophysics Data System (ADS)

Fedorov, A. V.; Tropin, D. A.; Fomin, P. A.

2018-03-01

The paper deals with the problem of the structure of detonation waves in the silane-air mixture within the framework of mathematical model of a nonequilibrium gas dynamics. Detailed kinetic scheme of silane oxidation as well as the newly developed reduced kinetic model of detonation combustion of silane are used. On its basis the detonation wave (DW) structure in stoichiometric silane - air mixture and dependences of Chapman-Jouguet parameters of mixture on stoichiometric ratio between the fuel (silane) and an oxidizer (air) were obtained.

Characterizing human activity induced impulse and slip-pulse excitations through structural vibration

NASA Astrophysics Data System (ADS)

Pan, Shijia; Mirshekari, Mostafa; Fagert, Jonathon; Ramirez, Ceferino Gabriel; Chung, Albert Jin; Hu, Chih Chi; Shen, John Paul; Zhang, Pei; Noh, Hae Young

2018-02-01

Many human activities induce excitations on ambient structures with various objects, causing the structures to vibrate. Accurate vibration excitation source detection and characterization enable human activity information inference, hence allowing human activity monitoring for various smart building applications. By utilizing structural vibrations, we can achieve sparse and non-intrusive sensing, unlike pressure- and vision-based methods. Many approaches have been presented on vibration-based source characterization, and they often either focus on one excitation type or have limited performance due to the dispersion and attenuation effects of the structures. In this paper, we present our method to characterize two main types of excitations induced by human activities (impulse and slip-pulse) on multiple structures. By understanding the physical properties of waves and their propagation, the system can achieve accurate excitation tracking on different structures without large-scale labeled training data. Specifically, our algorithm takes properties of surface waves generated by impulse and of body waves generated by slip-pulse into account to handle the dispersion and attenuation effects when different types of excitations happen on various structures. We then evaluate the algorithm through multiple scenarios. Our method achieves up to a six times improvement in impulse localization accuracy and a three times improvement in slip-pulse trajectory length estimation compared to existing methods that do not take wave properties into account.

SEPAC flight software detailed design specifications, volume 1

NASA Technical Reports Server (NTRS)

1982-01-01

The detailed design specifications (as built) for the SEPAC Flight Software are defined. The design includes a description of the total software system and of each individual module within the system. The design specifications describe the decomposition of the software system into its major components. The system structure is expressed in the following forms: the control-flow hierarchy of the system, the data-flow structure of the system, the task hierarchy, the memory structure, and the software to hardware configuration mapping. The component design description includes details on the following elements: register conventions, module (subroutines) invocaton, module functions, interrupt servicing, data definitions, and database structure.

Nanomechanical Characterization of lD Nanomaterials for Structure and Energy Applications

NASA Astrophysics Data System (ADS)

Loya, Phillip Edward

Classical fracture mechanics and conventional dislocation based understanding of metal yield and failure was well researched and understood until the recent advancement of electron microscopy techniques and the ability to produce small-scale metal samples. Once a critical dimension with respect to grain or geometrical size for a metal was reached, the deformation and fracture behaviors began to deviate from traditional theories and predictions. Recent research has focused on one-dimensional (1D) nanomaterials produced from their bulk counterparts to probe corresponding mechanical behaviors. However, this could alter the intrinsic material properties due to modifications caused by the milling/machining process. In this thesis, metal nanowires/fibers produced by an alternative process, and samples with controlled defect density, were used to gain a fundamental understanding of the critical dimension effects and small-scale mechanical behavior of metals. Another important aspect of this thesis is the development of a state-of-the-art nanomechanical characterization technique in the transmission electron microscope, where a detailed structure-property relationship could be reliably established with unprecedented resolutions. In the first part, single crystalline silver fibers were grown with dimensions varying from 2mum down to 400 nm and investigated using an advanced in-situ method. A critical dimension was observed near 1mum, below which the yield stress began to increase and the number of deformation slip bands began to decrease. Secondly, single crystal Mo-alloy fibers produced by a similar technique were pre-strained to introduce pre-existing dislocations and simulate bulk characteristics. In-situ tensile test showed the pre-straining effect on the yield stress, and the existence of a negative strain rate sensitivity. Next, pristine Mo-alloy fibers were irradiated with He and Ar ions to test the effects of irradiation induced defects on their mechanical behaviors

Characterizing core-periphery structure of complex network by h-core and fingerprint curve

NASA Astrophysics Data System (ADS)

Li, Simon S.; Ye, Adam Y.; Qi, Eric P.; Stanley, H. Eugene; Ye, Fred Y.

2018-02-01

It is proposed that the core-periphery structure of complex networks can be simulated by h-cores and fingerprint curves. While the features of core structure are characterized by h-core, the features of periphery structure are visualized by rose or spiral curve as the fingerprint curve linking to entire-network parameters. It is suggested that a complex network can be approached by h-core and rose curves as the first-order Fourier-approach, where the core-periphery structure is characterized by five parameters: network h-index, network radius, degree power, network density and average clustering coefficient. The simulation looks Fourier-like analysis.

RF and structural characterization of new SRF films

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

A.-M. Valente-Feliciano,H. L. Phillips,C. E. Reece,X. Zhao,D. Gu,R. Lukaszew,B. Xiao,K. Seo

2009-09-01

In the past years, energetic vacuum deposition methods have been developed in different laboratories to improve Nb/Cu technology for superconducting cavities. Jefferson Lab is pursuing energetic condensation deposition via Electron Cyclotron Resonance. As part of this study, the influence of the deposition energy on the material and RF properties of the Nb thin film is investigated. The film surface and structure analyses are conducted with various techniques like X-ray diffraction, Transmission Electron Microscopy, Auger Electron Spectroscopy and RHEED. The microwave properties of the films are characterized on 50 mm disk samples with a 7.5 GHz surface impedance characterization system. Thismore » paper presents surface impedance measurements in correlation with surface and material characterization for Nb films produced on copper substrates with different bias voltages and also highlights emerging opportunities for developing multilayer SRF films with a new deposition system.« less

Thermodynamic and structural characterization of an antibody gel

PubMed Central

Esue, Osigwe; Xie, Anna X.; Kamerzell, Tim J.; Patapoff, Thomas W.

2013-01-01

Although extensively studied, protein–protein interactions remain highly elusive and are of increasing interest in drug development. We show the assembly of a monoclonal antibody, using multivalent carboxylate ions, into highly-ordered structures. While the presence and function of similar structures in vivo are not known, the results may present a possible unexplored area of antibody structure-function relationships. Using a variety of tools (e.g., mechanical rheology, electron microscopy, isothermal calorimetry, Fourier transform infrared spectroscopy), we characterized the physical, biochemical, and thermodynamic properties of these structures and found that citrate may interact directly with the amino acid residue histidine, after which the individual protein units assemble into a filamentous network gel exhibiting high elasticity and interfilament interactions. Citrate interacts exothermically with the monoclonal antibody with an association constant that is highly dependent on solution pH and temperature. Secondary structure analysis also reveals involvement of hydrophobic and aromatic residues. PMID:23425660

Porous electrode apparatus for electrodeposition of detailed metal structures or microelectronic interconnections

DOEpatents

Griffiths, Stewart K.; Nilson, Robert H.; Hruby, Jill M.

2002-01-01

An apparatus and procedure for performing microfabrication of detailed metal structures by electroforming metal deposits within small cavities. Two primary areas of application are: the LIGA process which manufactures complex three-dimensional metal parts and the damascene process used for electroplating line and via interconnections of microelectronic devices. A porous electrode held in contact or in close proximity with a plating substrate or mold top to ensure one-dimensional and uniform current flow into all mold cavities is used. Electrolyte is pumped over the exposed surface of the porous electrode to ensure uniform ion concentrations at this external surface. The porous electrode prevents electrolyte circulation within individual mold cavities, avoiding preferential enhancement of ion transport in cavities having favorable geometries. Both current flow and ion transport are one-dimensional and identical in all mold cavities, so all metal deposits grow at the same rate eliminating nonuniformities of the prior art.

Detailed fault structure of the Tarutung Pull-Apart Basin in Sumatra, Indonesia, derived from local earthquake data

NASA Astrophysics Data System (ADS)

Muksin, Umar; Haberland, Christian; Nukman, Mochamad; Bauer, Klaus; Weber, Michael

2014-12-01

The Tarutung Basin is located at a right step-over in the northern central segment of the dextral strike-slip Sumatran Fault System (SFS). Details of the fault structure along the Tarutung Basin are derived from the relocations of seismicity as well as from focal mechanism and structural geology. The seismicity distribution derived by a 3D inversion for hypocenter relocation is clustered according to a fault-like seismicity distribution. The seismicity is relocated with a double-difference technique (HYPODD) involving the waveform cross-correlations. We used 46,904 and 3191 arrival differences obtained from catalogue data and cross-correlation analysis, respectively. Focal mechanisms of events were analyzed by applying a grid search method (HASH code). Although there is no significant shift of the hypocenters (10.8 m in average) and centroids (167 m in average), the application of the double difference relocation sharpens the earthquake distribution. The earthquake lineation reflects the fault system, the extensional duplex fault system, and the negative flower structure within the Tarutung Basin. The focal mechanisms of events at the edge of the basin are dominantly of strike-slip type representing the dextral strike-slip Sumatran Fault System. The almost north-south striking normal fault events along extensional zones beneath the basin correlate with the maximum principal stress direction which is the direction of the Indo-Australian plate motion. The extensional zones form an en-echelon pattern indicated by the presence of strike-slip faults striking NE-SW to NW-SE events. The detailed characteristics of the fault system derived from the seismological study are also corroborated by structural geology at the surface.

High Definition Confocal Imaging Modalities for the Characterization of Tissue-Engineered Substitutes.

PubMed

Mayrand, Dominique; Fradette, Julie

2018-01-01

Optimal imaging methods are necessary in order to perform a detailed characterization of thick tissue samples from either native or engineered tissues. Tissue-engineered substitutes are featuring increasing complexity including multiple cell types and capillary-like networks. Therefore, technical approaches allowing the visualization of the inner structural organization and cellular composition of tissues are needed. This chapter describes an optical clearing technique which facilitates the detailed characterization of whole-mount samples from skin and adipose tissues (ex vivo tissues and in vitro tissue-engineered substitutes) when combined with spectral confocal microscopy and quantitative analysis on image renderings.

Physicochemical characterization and structural evaluation of a specific 2:1 cocrystal of naproxen-nicotinamide.

PubMed

Ando, Shigeru; Kikuchi, Junko; Fujimura, Yuko; Ida, Yasuo; Higashi, Kenjirou; Moribe, Kunikazu; Yamamoto, Keiji

2012-09-01

Physicochemical characterization and structural evaluation of a 2:1 naproxen-nicotinamide cocrystal were performed. The 2:1 cocrystal showed rapid naproxen dissolution and less water vapor adsorption, indicating better pharmaceutical properties of naproxen. The unique 2:1 cocrystal formation was evaluated by solid-state nuclear magnetic resonance (NMR). The assignments of all H and (13) C peaks for naproxen and the cocrystal were performed using dipolar-insensitive nuclei enhanced by polarization transfer and (1) H-(13) C cross-polarization (CP)-heteronuclear correlation (HETCOR) NMR measurements. The (13) C chemical shift revealed that two naproxen molecules and one nicotinamide molecule existed in the asymmetric unit of the cocrystal. The (1) H chemical shifts indicated that the carboxylic group of the naproxen in the cocrystal was nonionized, and the CH-π interaction between naproxens was very strong. From the (1) H-(13) C CP-HETCOR NMR spectrum with contact time of 5 ms, two different synthons, carboxylic acid-amide and carboxylic acid-pyridine ring, were found between naproxen and nicotinamide. Single-crystal X-ray analysis, which supported the solid-state NMR results, clarified the geometry and intermolecular interactions in more detail. The structure is unique among pharmaceutical cocrystals because each carboxyl group of the two naproxens formed different intermolecular synthons. Copyright © 2012 Wiley Periodicals, Inc.

SU-E-T-170: Characterization of the Location, Extent, and Proximity to Critical Structures of Target Volumes Provides Detail for Improved Outcome Predictions Among Pancreatic Cancer Patients

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

Cheng, Z; Moore, J; Rosati, L

Purpose: In radiotherapy, size, location and proximity of the target to critical structures influence treatment decisions. It has been shown that proximity of the target predicts dosimetric sparing of critical structures. In addition to dosimetry, precise location of disease has further implications such as tumor invasion, or proximity to major arteries that inhibit surgery. Knowledge of which patients can be converted to surgical candidates by radiation may have high impact on future treat/no-treat decisions. We propose a method to improve our characterization of the location of pancreatic cancer and treatment volume extent with respect to nearby arteries with the goalmore » of developing features to improve clinical predictions and decisions. Methods: Oncospace is a local learning health system that systematically captures clinical outcomes and all aspects of radiotherapy treatment plans, including overlap volume histograms (OVH) – a measure of spatial relationships between two structures. Minimum and maximum distances of PTV and OARs based on OVH, PTV volume, anatomic location by ICD-9 code, and surgical outcome were queried. Normalized distance to center from the left and right kidney was calculated to indicate tumor location and laterality. Distance to critical arteries (celiac, superior mesenteric, common hepatic) is validated by surgical status (borderline resectable, locally advanced converted to resectable). Results: There were 205 pancreas stereotactic body radiotherapy patients treated from 2009–2015 queried. Location/laterality of tumor based on kidney OVH show strong trends between location by OVH and by ICD-9. Compared to the locally advanced group, the borderline resectable group showed larger geometrical distance from critical arteries (p=0.03). Conclusion: Our platform enabled analysis of shape/size-location relationships. These data suggest that PTV volume and attention to distance between PTVs and surrounding OARs and major arteries may be

Biophysical characterization of α-synuclein and its controversial structure

PubMed Central

Alderson, T Reid; Markley, John L

2013-01-01

α-synuclein, a presynaptic protein of poorly defined function, constitutes the main component of Parkinson disease-associated Lewy bodies. Extensive biophysical investigations have provided evidence that isolated α-synuclein is an intrinsically disordered protein (IDP) in vitro. Subsequently serving as a model IDP in numerous studies, α-synuclein has aided in the development of many technologies used to characterize IDPs and arguably represents the most thoroughly analyzed IDP to date. Recent reports, however, have challenged the disordered nature of α-synuclein inside cells and have instead proposed a physiologically relevant helical tetramer. Despite α-synuclein’s rich biophysical history, a single coherent picture has not yet emerged concerning its in vivo structure, dynamics, and physiological role(s). We present herein a review of the biophysical discoveries, developments, and models pertinent to the characterization of α-synuclein’s structure and analysis of the native tetramer controversy. PMID:24634806

Structural and mechanical characterization of hybrid metallic-inorganic nanosprings

NASA Astrophysics Data System (ADS)

Habtoun, Sabrina; Houmadi, Said; Reig, Benjamin; Pouget, Emilie; Dedovets, Dmytro; Delville, Marie-Hélène; Oda, Reiko; Cristiano, Fuccio; Bergaud, Christian

2017-10-01

Silica nanosprings (NS) are fabricated by a sol-gel deposition of silica precursors onto a template made of self-assembled organic chiral nanostructures. They are deposited and assembled on microstructured silicon substrates, and then metallized and clamped in a single lithography-free step using a focused ion beam (FIB). The resulting suspended hybrid metallic/inorganic NS are then characterized with high-resolution transmission electron microscopy (HRTEM) and scanning TEM/energy-dispersive X-ray spectroscopy (STEM/EDX), showing the atomic structure of the metallic layer. Three-point bending tests are also carried out using an atomic force microscope (AFM) and supported by finite element method (FEM) simulation with COMSOL Multiphysics allowing the characterization of the mechanical behavior and the estimation of the stiffness of the resulting NS. The information obtained on the structural and mechanical properties of the NS is discussed for future nano-electro-mechanical system (NEMS) applications.

Strategies for the profiling, characterisation and detailed structural analysis of N-linked oligosaccharides.

PubMed

Tharmalingam, Tharmala; Adamczyk, Barbara; Doherty, Margaret A; Royle, Louise; Rudd, Pauline M

2013-02-01

Many post-translational modifications, including glycosylation, are pivotal for the structural integrity, location and functional activity of glycoproteins. Sub-populations of proteins that are relocated or functionally changed by such modifications can change resting proteins into active ones, mediating specific effector functions, as in the case of monoclonal antibodies. To ensure safe and efficacious drugs it is essential to employ appropriate robust, quantitative analytical strategies that can (i) perform detailed glycan structural analysis, (ii) characterise specific subsets of glycans to assess known critical features of therapeutic activities (iii) rapidly profile glycan pools for at-line monitoring or high level batch to batch screening. Here we focus on these aspects of glycan analysis, showing how state-of-the-art technologies are required at all stages during the production of recombinant glycotherapeutics. These data can provide insights into processing pathways and suggest markers for intervention at critical control points in bioprocessing and also critical decision points in disease and drug monitoring in patients. Importantly, these tools are now enabling the first glycome/genome studies in large populations, allowing the integration of glycomics into other 'omics platforms in a systems biology context.

Analytical Strategies Involved in the Detailed Componential Characterization of Biooil Produced from Lignocellulosic Biomass

PubMed Central

Li, Guo-Sheng; Wei, Xian-Yong

2017-01-01

Elucidation of chemical composition of biooil is essentially important to evaluate the process of lignocellulosic biomass (LCBM) conversion and its upgrading and suggest proper value-added utilization like producing fuel and feedstock for fine chemicals. Although the main components of LCBM are cellulose, hemicelluloses, and lignin, the chemicals derived from LCBM differ significantly due to the various feedstock and methods used for the decomposition. Biooil, produced from pyrolysis of LCBM, contains hundreds of organic chemicals with various classes. This review covers the methodologies used for the componential analysis of biooil, including pretreatments and instrumental analysis techniques. The use of chromatographic and spectrometric methods was highlighted, covering the conventional techniques such as gas chromatography, high performance liquid chromatography, Fourier transform infrared spectroscopy, nuclear magnetic resonance, and mass spectrometry. The combination of preseparation methods and instrumental technologies is a robust pathway for the detailed componential characterization of biooil. The organic species in biooils can be classified into alkanes, alkenes, alkynes, benzene-ring containing hydrocarbons, ethers, alcohols, phenols, aldehydes, ketones, esters, carboxylic acids, and other heteroatomic organic compounds. The recent development of high resolution mass spectrometry and multidimensional hyphenated chromatographic and spectrometric techniques has considerably elucidated the composition of biooils. PMID:29387086

Structural characterization of Co-Re superlattices

NASA Astrophysics Data System (ADS)

Melo, L. V.; Trindade, I.; From, M.; Freitas, P. P.; Teixeira, N.; da Silva, M. F.; Soares, J. C.

1991-12-01

Co-Re superlattices were prepared with nominal periodicities of 65-67 Å and varying bilayer composition. The structural characterization was made by x-ray diffraction and Rutherford backscattering spectrometry (RBS). First, second, and third order satellites are observed in the x-ray diffractogram at 2θ values and with intensities close to those predicted by simulation. This confirms the coherence of the superlattice. RBS measurements combined with RUMP simulations give information on interface sharpness and the absolute thicknesses of the Co and Re layers. Discrepancies between the experimental and simulated diffractograms are found for Co thicknesses below 18 Å.

Printing Fabrication of Bulk Heterojunction Solar Cells and In Situ Morphology Characterization.

PubMed

Liu, Feng; Ferdous, Sunzida; Wan, Xianjian; Zhu, Chenhui; Schaible, Eric; Hexemer, Alexander; Wang, Cheng; Russell, Thomas P

2017-01-29

Polymer-based materials hold promise as low-cost, flexible efficient photovoltaic devices. Most laboratory efforts to achieve high performance devices have used devices prepared by spin coating, a process that is not amenable to large-scale fabrication. This mismatch in device fabrication makes it difficult to translate quantitative results obtained in the laboratory to the commercial level, making optimization difficult. Using a mini-slot die coater, this mismatch can be resolved by translating the commercial process to the laboratory and characterizing the structure formation in the active layer of the device in real time and in situ as films are coated onto a substrate. The evolution of the morphology was characterized under different conditions, allowing us to propose a mechanism by which the structures form and grow. This mini-slot die coater offers a simple, convenient, material efficient route by which the morphology in the active layer can be optimized under industrially relevant conditions. The goal of this protocol is to show experimental details of how a solar cell device is fabricated using a mini-slot die coater and technical details of running in situ structure characterization using the mini-slot die coater.

Characterization of Creases in Polymers for Adaptive Origami Structures (Postprint)

DTIC Science & Technology

2014-10-01

Techniques employed in origami are of interest for the design of actuating structures with multiple defined geometric states. Most research in this...studied in detail. Understanding creasing is crucial for establishing material selection guidelines in origami engineering applications...Identification of the precise failure mechanisms is critical for understanding the residual fold angle and selecting optimal materials for specific origami

Seismic and structural characterization of the fluid bypass system using 3D and partial stack seismic from passive margin: inside the plumbing system.

NASA Astrophysics Data System (ADS)

Iacopini, David; Maestrelli, Daniele; Jihad, Ali; Bond, Clare; Bonini, Marco

2017-04-01

In recent years enormous attention has been paid to the understanding of the process and mechanism controlling the gas seepage and more generally the fluid expulsion affecting the earth system from onshore to offshore environment. This is because of their demonstrated impact to our environment, climate change and during subsea drilling operation. Several example from active and paleo system has been so far characterized and proposed using subsurface exploration, geophysical and geochemical monitoring technology approaches with the aims to explore what trigger and drive the overpressure necessary maintain the fluid/gas/material expulsion and what are the structure that act as a gateway for gaseous fluid and unconsolidated rock. In this contribution we explore a series of fluid escape structure (ranging from seepage pipes to large blowout pipes structure of km length) using 3D and partial stack seismic data from two distinctive passive margin from the north sea (Loyal field, West Shetland) and the Equatorial Brazil (Ceara' Basin). We will focuses on the characterization of the plumbing system internal architecture and, for selected example, exploring the AVO response (using partial stack) of the internal fluid/unconsolidated rock. The detailed seismic mapping and seismic attributes analysis of the conduit system helped us to recover some detail from the signal response of the chimney internal structures. We observed: (1) small to medium seeps and pipes following structural or sedimentary discontinuities (2) large pipes (probably incipient mud volcanoes) and blowup structures propagating upward irrespective of pre-existing fault by hydraulic fracturing and assisted by the buoyancy of a fluidised and mobilised mud-hydrocarbon mixture. The reflector termination observed inside the main conduits, the distribution of stacked bright reflectors and the AVO analysis suggests an evolution of mechanisms (involving mixture of gas, fluid and probably mud) during pipe birth and

PREFACE: Symposium 1: Advanced Structure Analysis and Characterization of Ceramic Materials

NASA Astrophysics Data System (ADS)

Yashima, Masatomo

2011-05-01

Preface to Symposium 1 (Advanced Structure Analysis and Characterization of Ceramic Materials) of the International Congress of Ceramics III, held 14-18 November 2010 in Osaka, Japan Remarkable developments have been made recently in the structural analysis and characterization of inorganic crystalline and amorphous materials, such as x-ray, neutron, synchrotron and electron diffraction, x-ray/neutron scattering, IR/Raman scattering, NMR, XAFS, first-principle calculations, computer simulations, Rietveld analysis, the maximum-entropy method, in situ measurements at high temperatures/pressures and electron/nuclear density analysis. These techniques enable scientists to study not only static and long-range periodic structures but also dynamic and short-/intermediate-range structures. Multi-scale characterization from the electron to micrometer levels is becoming increasingly important as a means of understanding phenomena at the interfaces, grain boundaries and surfaces of ceramic materials. This symposium has discussed the structures and structure/property relationships of various ceramic materials (electro, magnetic and optical ceramics; energy and environment related ceramics; bio-ceramics; ceramics for reliability secure society; traditional ceramics) through 38 oral presentations including 8 invited lectures and 49 posters. Best poster awards were given to six excellent poster presentations (Y-C Chen, Tokyo Institute of Technology; C-Y Chung, Tohoku University; T Stawski, University of Twente; Y Hirano, Nagoya Institute of Technology; B Bittova, Charles University Prague; Y Onodera, Kyoto University). I have enjoyed working with my friends in the ICC3 conference. I would like to express special thanks to other organizers: Professor Scott T Misture, Alfred University, USA, Professor Xiaolong Chen, Institute of Physics, CAS, China, Professor Takashi Ida, Nagoya Institute of Technology, Japan, Professor Isao Tanaka, Kyoto University, Japan. I also acknowledge the

Structural and optical characterization of NiSe film grown by screen-printing method

NASA Astrophysics Data System (ADS)

Sharma, Kapil; Sharma, D. K.; Dwivedi, D. K.; Kumar, Vipin

2018-05-01

In present investigation NiSe films were grown by economical screen-printing method. Optimum conditions for growing good quality screen-printed films were found. The films were characterized for their structural and optical properties. The polycrystalline nature of films with hexagonal structure was confirmed through XRD analysis. Direct type of optical band gap of 1.75 eV for the NiSe film was confirmed by optical characterization.

Structural and optical characterization of the propolis films

NASA Astrophysics Data System (ADS)

Drapak, S. I.; Bakhtinov, A. P.; Gavrylyuk, S. V.; Drapak, I. T.; Kovalyuk, Z. D.

2006-10-01

We have performed structural and optical characterizations of the propolis (an organic entity of biological nature) films grown on various non-organic substrates. The films were grown from a propolis melt or a propolis alcohol solution. The crystal structure has been observed in the films precipitated from the solution onto substrates such as an amorphous glass and sapphire or semiconductor indium monoselenide. For any growth method, the propolis film is a semiconductor with the bandgap of 3.07 eV at 300 K that is confirmed by a maximum in photoluminescence spectra at 2.86 eV. We argue that propolis films might be used in various optoelectronic device applications.

Beyond Vmax and Km: How details of enzyme function influence geochemical cycles

NASA Astrophysics Data System (ADS)

Steen, A. D.

2015-12-01

Enzymes catalyze the vast majority of chemical reactions relevant to geomicrobiology. Studies of the activities of enzymes in environmental systems often report Vmax (the maximum possible rate of reaction; often proportional to the concentration of enzymes in the system) and sometimes Km (a measure of the affinity between enzymes and their substrates). However, enzyme studies - particularly those related to enzymes involved in organic carbon oxidation - are often limited to only those parameters, and a relatively limited and mixed set of enzymes. Here I will discuss some novel methods to assay and characterize the specific sets of enzymes that may be important to the carbon cycle in aquatic environments. First, kinetic experiments revealed the collective properties of the complex mixtures of extracellular peptidases that occur where microbial communities are diverse. Crystal structures combined with biochemical characterization of specific enzymes can yield more detailed information about key steps in organic carbon transformations. These new techniques have the potential to provide mechanistic grounding to geomicrobiological models.

Electrochemical characterization of p(+)n and n(+)p diffused InP structures

NASA Technical Reports Server (NTRS)

Wilt, David M.; Faur, Maria; Faur, Mircea; Goradia, M.; Vargas-Aburto, Carlos

1993-01-01

The relatively well documented and widely used electrolytes for characterization and processing of Si and GaAs-related materials and structures by electrochemical methods are of little or no use with InP because the electrolytes presently used either dissolve the surface preferentially at the defect areas or form residual oxides and introduce a large density of surface states. Using an electrolyte which was newly developed for anodic dissolution of InP, and was named the 'FAP' electrolyte, accurate characterization of InP related structures including nature and density of surface states, defect density, and net majority carrier concentration, all as functions of depth was performed. A step-by-step optimization of n(+)p and p(+)n InP structures made by thermal diffusion was done using the electrochemical techniques, and resulted in high performance homojunction InP structures.

Structural characterization of nonactive site, TrkA-selective kinase inhibitors

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

Su, Hua-Poo; Rickert, Keith; Burlein, Christine

Current therapies for chronic pain can have insufficient efficacy and lead to side effects, necessitating research of novel targets against pain. Although originally identified as an oncogene, Tropomyosin-related kinase A (TrkA) is linked to pain and elevated levels of NGF (the ligand for TrkA) are associated with chronic pain. Antibodies that block TrkA interaction with its ligand, NGF, are in clinical trials for pain relief. Here, we describe the identification of TrkA-specific inhibitors and the structural basis for their selectivity over other Trk family kinases. The X-ray structures reveal a binding site outside the kinase active site that uses residuesmore » from the kinase domain and the juxtamembrane region. Three modes of binding with the juxtamembrane region are characterized through a series of ligand-bound complexes. The structures indicate a critical pharmacophore on the compounds that leads to the distinct binding modes. The mode of interaction can allow TrkA selectivity over TrkB and TrkC or promiscuous, pan-Trk inhibition. This finding highlights the difficulty in characterizing the structure-activity relationship of a chemical series in the absence of structural information because of substantial differences in the interacting residues. These structures illustrate the flexibility of binding to sequences outside of—but adjacent to—the kinase domain of TrkA. This knowledge allows development of compounds with specificity for TrkA or the family of Trk proteins.« less

Characterizing structures on borehole images and logging data of the Nankai trough accretionary prism: new insights

NASA Astrophysics Data System (ADS)

Jurado, Maria Jose

2016-04-01

IODP has extensively used the D/V Chikyu to drill the Kumano portion of the Nankai Trough, including two well sites within the Kumano Basin. IODP Expeditions 338 and 348 drilled deep into the inner accretionary prism south of the Kii Peninsula collecting a suite of LWD data, including natural gamma ray, electrical resistivity logs and borehole images, suitable to characterize structures (fractures and faults) inside the accretionary prism. Structural interpretation and analysis of logging-while-drilling data in the deep inner prism revealed intense deformation of a generally homogenous lithology characterized by bedding that dips steeply (60-90°) to the NW, intersected by faults and fractures. Multiple phases of deformation are characterized. IODP Expedition borehole images and LWD data acquired in the last decade in previous and results of NantroSEIZE IODP Expeditions (314, 319) were also analyzed to investigate the internal geometries and structures of the Nankai Trough accretionary prism. This study focused mainly on the characterization of the different types of structures and their specific position within the accretionary prism structures. New structural constraints and methodologies as well as a new approach to the characterization of study of active structures inside the prism will be presented.

GLASS: detailed structure of high redshift galaxies from HST grism spectroscopy

NASA Astrophysics Data System (ADS)

Jones, Tucker; Treu, Tommaso; Schmidt, Kasper B.; Wang, Xin; Brammer, Gabriel; Glass

2015-01-01

The Grism Lens-Amplified Survey from Space (GLASS) is obtaining slitless near-IR spectroscopy of 10 galaxy clusters selected for their strong lensing properties, including all six Hubble Frontier Fields. The GLASS survey will have gathered more than ten thousand spectra upon completion in early 2015. Slitless grism spectra are ideal for mapping emission lines such as [O II], [O III], and Hα at z=1-3 as well as Lyα at z>6. The combination of strong gravitational lensing and HST's diffraction limit provides excellent sensitivity (~1e-18 erg/s/cm2 RMS) with spatial resolution as fine as 100 pc for highly magnified sources, and ~500 pc for less magnified sources near the edge of the field of view. This enables precise measurements of metallicity gradients, the distribution of star formation, and other details of the physical structure of high redshift galaxies with masses as low as ~107 M⊙ at z=2. I will discuss measurements of these physical properties and implications for galaxy evolution based on the largest sample available to date with such high resolution at z>1.

Detailed Northern Anatolian Fault Zone crustal structure from receiver functions

NASA Astrophysics Data System (ADS)

Cornwell, D. G.; Kahraman, M.; Thompson, D. A.; Houseman, G. A.; Rost, S.; Turkelli, N.; Teoman, U.; Altuncu Poyraz, S.; Gülen, L.; Utkucu, M.

2013-12-01

locations at either of the NAFZ fault branches. We observe first-order differences in crustal structure between the crustal blocks that are separated by the faults. Each crustal block also contains regions of strong anisotropy at various depths that will be analyzed further with the full seismological dataset and compared to petrofabric analyses of exhumed fault segments. We will compare our results with other seismological imaging techniques to attempt to resolve the distribution of fault zone deformation with respect to depth. This information will be useful to other complementary Faultlab techniques that will add a detailed insight into the fault structure and dynamics of the NAFZ and contribute more broadly into ongoing research into major strike-slip fault zones.

Mechanical and structural characterizations of gamma- and alpha-alumina nanofibers

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

Vahtrus, Mikk; Umalas, Madis; Polyakov, Boris

2015-09-15

We investigate the applicability of alumina nanofibers as a potential reinforcement material in ceramic matrix compounds by comparing the mechanical properties of individual nanofibers before and after annealing at 1400 °C. Mechanical testing is performed inside a scanning electron microscope (SEM), which enables observation in real time of the deformation and fracture of the fibers under loading, thereby providing a close-up inspection of the freshly fractured area in vacuum. Improvement of both the Young's modulus and the breaking strength for annealed nanofibers is demonstrated. Mechanical testing is supplemented with the structural characterization of the fibers before and after annealing usingmore » SEM, transmission electron microscopy and X-ray diffraction methods. - Highlights: • Mechanical properties of individual alumina nanofibers were measured using in situ SEM cantilevered beam bending technique. • Improvement of mechanical properties of the alumina fibers after annealing at 1400 °C is demonstrated. • Formation of branched structures is demonstrated and their mechanical properties are studied. • XRD and electron microscopy were used for structural characterization of untreated and annealed nanofibers.« less

Characterizing Thematized Derivative Schema by the Underlying Emergent Structures

ERIC Educational Resources Information Center

Garcia, Mercedes; Llinares, Salvador; Sanchez-Matamoros, Gloria

2011-01-01

This paper reports on different underlying structures of the derivative schema of three undergraduate students that were considered to be at the trans level of development of the derivative schema (action-process-object-schema). The derivative schema is characterized in terms of the students' ability to explicitly transfer the relationship between…

Dispersed metal cluster catalysts by design. Synthesis, characterization, structure, and performance

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

Arslan, Ilke; Dixon, David A.; Gates, Bruce C.

2015-09-30

To understand the class of metal cluster catalysts better and to lay a foundation for the prediction of properties leading to improved catalysts, we have synthesized metal catalysts with well-defined structures and varied the cluster structures and compositions systematically—including the ligands bonded to the metals. These ligands include supports and bulky organics that are being tuned to control both the electron transfer to or from the metal and the accessibility of reactants to influence catalytic properties. We have developed novel syntheses to prepare these well-defined catalysts with atomic-scale control the environment by choice and placement of ligands and applied state-of-themore » art spectroscopic, microscopic, and computational methods to determine their structures, reactivities, and catalytic properties. The ligands range from nearly flat MgO surfaces to enveloping zeolites to bulky calixarenes to provide controlled coverages of the metal clusters, while also enforcing unprecedented degrees of coordinative unsaturation at the metal site—thereby facilitating bonding and catalysis events at exposed metal atoms. With this wide range of ligand properties and our arsenal of characterization tools, we worked to achieve a deep, fundamental understanding of how to synthesize robust supported and ligand-modified metal clusters with controlled catalytic properties, thereby bridging the gap between active site structure and function in unsupported and supported metal catalysts. We used methods of organometallic and inorganic chemistry combined with surface chemistry for the precise synthesis of metal clusters and nanoparticles, characterizing them at various stages of preparation and under various conditions (including catalytic reaction conditions) and determining their structures and reactivities and how their catalytic properties depend on their compositions and structures. Key characterization methods included IR, NMR, and EXAFS spectroscopies to

Structural Characterization of Bimetallic Nanocrystal Electrocatalysts

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

Cullen, David A

2016-01-01

Late transition metal nanocrystals find applications in heterogeneous catalysis such as plasmon-enhanced catalysis and as electrode materials for fuel cells, a zero-emission and sustainable energy technology. Their commercial viability for automotive transportation has steadily increased in recent years, almost exclusively due to the discovery of more efficient bimetallic nanocatalysts for the oxygen reduction reaction (ORR) at the cathode. Despite improvements to catalyst design, achieving high activity while maintaining durability is essential to further enhance their performance for this and other important applications in catalysis. Electronic effects arising from the generation of metal-metal interfaces, from plasmonic metals, and from lattice distortions,more » can vastly improve sorption properties at catalytic surfaces, while increasing durability.[1] Multimetallic lattice-strained nanoparticles are thus an interesting opportunity for fundamental research.[2,3] A colloidal synthesis approach is demonstrated to produce AuPd alloy and Pd@Au core-shell nanoicosahedra as catalysts for electro-oxidations. The nanoparticles are characterized using aberration-corrected scanning transmission electron microscopy (ac-STEM) and large solid angle energy dispersive X-ray spectroscopy (EDS) on an FEI Talos 4-detector STEM/EDS system. Figure 1 shows bright-field (BF) and high-angle annular dark-field (HAADF) ac-STEM images of the alloy and core-shell nanoicosahedra together with EDS line-scans and elemental maps. These structures are unique in that the presence of twin boundaries, alloying, and core-shell morphology could create highly strained surfaces and interfaces. The shell thickness of the core-shell structures observed in HAADF-STEM images is tuned by adjusting the ratio between metal precursors (Figure 2a-f) to produce shells ranging from a few to several monolayers. Specific activity was measured in ethanol electro-oxidation to examine the effect of shell

Attenuation tomography in the western central Andes: A detailed insight into the structure of a magmatic arc

NASA Astrophysics Data System (ADS)

Haberland, Christian; Rietbrock, Andreas

2001-06-01

High-quality data from 1498 local earthquakes recorded by the PISCO '94 (Proyecto de Investigatión Sismológica de la Cordillera Occidental, 1994) and ANCORP '96 (Andean Continental Research Project, 1996) temporary seismological networks allowed the detailed determination of the three-dimensional (3-D) attenuation structure (Qp-1) beneath the recent magmatic arc in the western central Andes (20° to 24°S). Assuming a frequency-independent Qp-1 in a frequency band between 1 and 30 Hz, whole path attenuation (t*) was estimated from the amplitude spectra of the P waves using spectral ratios and a spectral inversion technique. The damped least squares inversion (tomography) of the data reveals a complex attenuation structure. Crust and mantle of the forearc and subducting slab are generally characterized by low attenuation (Qp > 1000). Crust and mantle beneath the magmatic arc show elevated attenuation. The strongest anomaly of extremely low Qp is found in the crust between 22° and 23°S beneath the recent volcanic arc (Qp < 100). N-S variations can be observed: The western flank of the crustal attenuation anomaly follows the curved course of the volcanic front. North of 21°S the attenuation is less developed. In the northern part of the study area the low-Qp zone penetrates in the forearc mantle down to the subducting slab. In the south a deeper zone of high attenuation is resolved between 23° and 24°S directly above the subducting slab. Low Qp in the mantle correlates with earthquake clusters. The strong crustal attenuation is confined to the distribution of young ignimbrites and silicic volcanism and is interpreted as a thermally weakened zone with partial melts. The attenuation pattern in the upper mantle might reflect the variable extent of the asthenosphere and maps variations of subduction-related hydration processes in the mantle wedge from slab-derived fluids.

E-detailing: information technology applied to pharmaceutical detailing.

PubMed

Montoya, Isaac D

2008-11-01

E-detailing can be best described as the use of information technology in the field of pharmaceutical detailing. It is becoming highly popular among pharmaceutical companies because it maximizes the time of the sales force, cuts down the cost of detailing and increases physician prescribing. Thus, the application of information technology is proving to be beneficial to both physicians and pharmaceutical companies. When e-detailing was introduced in 1996, it was limited to the US; however, numerous other countries soon adopted this novel approach to detailing and now it is popular in many developed nations. The objective of this paper is to demonstrate the rapid growth of e-detailing in the field of pharmaceutical marketing. A review of e-detailing literature was conducted in addition to personal conversations with physicians. E-detailing has the potential to reduce marketing costs, increase accessibility to physicians and offer many of the advantages of face-to-face detailing. E-detailing is gaining acceptance among physicians because they can access the information of a pharmaceutical product at their own time and convenience. However, the drug safety aspect of e-detailing has not been examined and e-detailing remains a supplement to traditional detailing and is not yet a replacement to it.

Effect of crumb cellular structure characterized by image analysis on cake softness.

PubMed

Dewaest, Marine; Villemejane, Cindy; Berland, Sophie; Neron, Stéphane; Clement, Jérôme; Verel, Aliette; Michon, Camille

2018-06-01

Sponge cake is a cereal product characterized by an aerated crumb and appreciated for its softness. When formulating such product, it is interesting to be able to characterize the crumb structure using image analysis and to bring knowledge about the effects of the crumb cellular structure on its mechanical properties which contribute to softness. An image analysis method based on mathematical morphology was adapted from the one developed for bread crumb. In order to evaluate its ability to discriminate cellular structures, series of cakes were prepared using two rather similar emulsifiers but also using flours with different aging times before use. The mechanical properties of the crumbs of these different cakes were also characterized. It allowed a cell structure classification taking into account cell size and homogeneity, but also cell wall thickness and the number of holes in the walls. Interestingly, the cellular structure differences had a larger impact on the aerated crumb Young modulus than the wall firmness. Increasing the aging time of flour before use leads to the production of firmer crumbs due to coarser and inhomogeneous cellular structures. Changing the composition of the emulsifier may change the cellular structure and, depending on the type of the structural changes, have an impact on the firmness of the crumb. Cellular structure rather than cell wall firmness was found to impact cake crumb firmness. The new fast and automated tool for cake crumb structure analysis allows detecting quickly any change in cell size or homogeneity but also cell wall thickness and number of holes in the walls (openness degree). To obtain a softer crumb, it seems that options are to decrease the cell size and the cell wall thickness and/or to increase the openness degree. It is then possible to easily evaluate the effects of ingredients (flour composition, emulsifier …) or change in the process on the crumb structure and thus its softness. Moreover, this image

Characterizing structural transitions using localized free energy landscape analysis.

PubMed

Banavali, Nilesh K; Mackerell, Alexander D

2009-01-01

Structural changes in molecules are frequently observed during biological processes like replication, transcription and translation. These structural changes can usually be traced to specific distortions in the backbones of the macromolecules involved. Quantitative energetic characterization of such distortions can greatly advance the atomic-level understanding of the dynamic character of these biological processes. Molecular dynamics simulations combined with a variation of the Weighted Histogram Analysis Method for potential of mean force determination are applied to characterize localized structural changes for the test case of cytosine (underlined) base flipping in a GTCAGCGCATGG DNA duplex. Free energy landscapes for backbone torsion and sugar pucker degrees of freedom in the DNA are used to understand their behavior in response to the base flipping perturbation. By simplifying the base flipping structural change into a two-state model, a free energy difference of upto 14 kcal/mol can be attributed to the flipped state relative to the stacked Watson-Crick base paired state. This two-state classification allows precise evaluation of the effect of base flipping on local backbone degrees of freedom. The calculated free energy landscapes of individual backbone and sugar degrees of freedom expectedly show the greatest change in the vicinity of the flipping base itself, but specific delocalized effects can be discerned upto four nucleotide positions away in both 5' and 3' directions. Free energy landscape analysis thus provides a quantitative method to pinpoint the determinants of structural change on the atomic scale and also delineate the extent of propagation of the perturbation along the molecule. In addition to nucleic acids, this methodology is anticipated to be useful for studying conformational changes in all macromolecules, including carbohydrates, lipids, and proteins.

Sizing Single Cantilever Beam Specimens for Characterizing Facesheet/Core Peel Debonding in Sandwich Structure

NASA Technical Reports Server (NTRS)

Ratcliffe, James G.

2010-01-01

This technical publication details part of an effort focused on the development of a standardized facesheet/core peel debonding test procedure. The purpose of the test is to characterize facesheet/core peel in sandwich structure, accomplished through the measurement of the critical strain energy release rate associated with the debonding process. Following an examination of previously developed tests and a recent evaluation of a selection of these methods, a single cantilever beam (SCB) specimen was identified as being a promising candidate for establishing such a standardized test procedure. The objective of the work described here was to begin development of a protocol for conducting a SCB test that will render the procedure suitable for standardization. To this end, a sizing methodology was developed to ensure appropriate SCB specimen dimensions are selected for a given sandwich system. Application of this method to actual sandwich systems yielded SCB specimen dimensions that would be practical for use. This study resulted in the development of a practical SCB specimen sizing method, which should be well-suited for incorporation into a standardized testing protocol.

Characterization of Structural and Configurational Properties of DNA by Atomic Force Microscopy.

PubMed

Meroni, Alice; Lazzaro, Federico; Muzi-Falconi, Marco; Podestà, Alessandro

2018-01-01

We describe a method to extract quantitative information on DNA structural and configurational properties from high-resolution topographic maps recorded by atomic force microscopy (AFM). DNA molecules are deposited on mica surfaces from an aqueous solution, carefully dehydrated, and imaged in air in Tapping Mode. Upon extraction of the spatial coordinates of the DNA backbones from AFM images, several parameters characterizing DNA structure and configuration can be calculated. Here, we explain how to obtain the distribution of contour lengths, end-to-end distances, and gyration radii. This modular protocol can be also used to characterize other statistical parameters from AFM topographies.

Detailed characterization of the LLNL imaging proton spectrometer

DOE PAGES

Rasmus, A. M.; Hazi, A. U.; Manuel, M. J. -E.; ...

2016-09-01

Here, ultra-intense short pulse lasers incident on solid targets (e.g., several um thick Au foils) produce well collimated, broad-energy-spectrum proton beams. These proton beams can be used to characterize magnetic fields, electric fields (through particle deflection), and density gradients (through collisions) in high energy-density systems. The LLNL-Imaging Proton Spectrometer (L-IPS) was designed and built for use with such laser produced proton beams. The L-IPS has an energy range of 50 keV-40 MeV with a resolving power (E/dE) of about 275 at 1 MeV and 21 at 20 MeV, as well as a single spatial imaging axis. The protons enter themore » diagnostic through a vertical slit, aligned with a magnetic field imposed by permanent magnets. The protons are deflected perpendicular to the magnetic field (and therefor slit), so that spatial information in the direction of the slit is preserved. The extent to which the protons are bent by the magnetic field depends on the energy, so that the energy of the protons can be resolved as well. The protons are then measured by image plates, in which a meta-stable state is excited by collisions with the protons, which can later be imaged by a scanner. In order to better characterize the dispersion and imaging capability of this diagnostic, a 3D finite element analysis solver is used to calculate the magnetic field of the L-IPS. Particle trajectories are then obtained via numerical integration to determine the dispersion relation of the L-IPS in both energy and angular space.« less

Electro-mechanical characterization of structural supercapacitors

NASA Astrophysics Data System (ADS)

Gallagher, T.; LaMaster, D.; Ciocanel, C.; Browder, C.

2012-04-01

The paper presents electrical and mechanical properties of structural supercapacitors and discusses limitations associated with the approach taken for the electrical properties evaluation. The structural supercapacitors characterized in this work had the electrodes made of carbon fiber weave, separator made of several cellulose based products, and the solid electrolyte made as PEGDGE based polymer blend. The reported electrical properties include capacitance and leakage resistance; the former was measured using cyclic voltammetry. Mechanical properties have been evaluated thorough tensile and three point bending tests performed on structural supercapacitor coupons. The results indicate that the separator material plays an important role on the electrical as well as mechanical properties of the structural capacitor, and that Celgard 3501 used as separator leads to most benefits for both mechanical and electrical properties. Specific capacitance and leakage resistance as high as 1.4kF/m3 and 380kΩ, respectively, were achieved. Two types of solid polymer electrolytes were used in fabrication, with one leading to higher and more consistent leakage resistance values at the expense of a slight decrease in specific capacitance when compared to the other SPE formulation. The ultimate tensile strength and modulus of elasticity of the developed power storage composite were evaluated at 466MPa and 18.9MPa, respectively. These values are 58% and 69% of the tensile strength and modulus of elasticity values measured for a single layer composite material made with the same type of carbon fiber and with a West System 105 epoxy instead of solid polymer electrolyte.

Characterization of seismic hazard and structural response by energy flux

USGS Publications Warehouse

Afak, E.

2000-01-01

Seismic safety of structures depends on the structure's ability to absorb the seismic energy that is transmitted from ground to structure. One parameter that can be used to characterize seismic energy is the energy flux. Energy flux is defined as the amount of energy transmitted per unit time through a cross-section of a medium, and is equal to kinetic energy multiplied by the propagation velocity of seismic waves. The peak or the integral of energy flux can be used to characterize ground motions. By definition, energy flux automatically accounts for site amplification. Energy flux in a structure can be studied by formulating the problem as a wave propagation problem. For buildings founded on layered soil media and subjected to vertically incident plane shear waves, energy flux equations are derived by modeling the buildings as an extension of the layered soil medium, and considering each story as another layer. The propagation of energy flux in the layers is described in terms of the upgoing and downgoing energy flux in each layer, and the energy reflection and transmission coefficients at each interface. The formulation results in a pair of simple finite-difference equations for each layer, which can be solved recursively starting from the bedrock. The upgoing and downgoing energy flux in the layers allows calculation of the energy demand and energy dissipation in each layer. The methodology is applicable to linear, as well as nonlinear structures. ?? 2000 Published by Elsevier Science Ltd.

Characterization of Microgravity Environment on Mir

NASA Technical Reports Server (NTRS)

Kim, Hyoung; Kaouk, Mohamed

2000-01-01

This paper presents the microgravity analysis results using dynamic response data collected during the first phase of the Mir Structural Dynamics Experiment (MiSDE). Although MiSDE was designed and performed to verify structural dynamic models, it also provided information for determining microgravity characteristics of the structure. This study analyzed ambient responses acquired during orbital day-to-night and night-to-day transitions, crew treadmill and ergometer exercises, and intentional crew activities. Acceleration levels for one-third octave bands were calculated to characterize the microgravity environment of the station. Spectrograms were also used to analyze the time transient nature of the responses. Detailed theoretical background and analysis results will also be included in the final draft.

Structure-from-Motion Approach for Characterization of Bioerosion Patterns Using UAV Imagery

PubMed Central

Genchi, Sibila A.; Vitale, Alejandro J.; Perillo, Gerardo M. E.; Delrieux, Claudio A.

2015-01-01

The aim of this work is to evaluate the applicability of the 3D model obtained through Structure-from-Motion (SFM) from unmanned aerial vehicle (UAV) imagery, in order to characterize bioerosion patterns (i.e., cavities for roosting and nesting) caused by burrowing parrots on a cliff in Bahía Blanca, Argentina. The combined use of SFM-UAV technology was successfully applied for the 3D point cloud model reconstruction. The local point density, obtained by means of a sphere of radius equal to 0.5 m, reached a mean value of 9749, allowing to build a high-resolution model (0.013 m) for resolving fine spatial details in topography. To test the model, we compared it with another point cloud dataset which was created using a low cost do-it-yourself terrestrial laser scanner; the results showed that our georeferenced model had a good accuracy. In addition, an innovative method for the detection of the bioerosion features was implemented, through the processing of data provided by SFM like color and spatial coordinates (particularly the y coordinate). From the 3D model, we also derived topographic calculations such as slope angle and surface roughness, to get associations between the surface topography and bioerosion features. PMID:25658392

Structure-from-motion approach for characterization of bioerosion patterns using UAV imagery.

PubMed

Genchi, Sibila A; Vitale, Alejandro J; Perillo, Gerardo M E; Delrieux, Claudio A

2015-02-04

The aim of this work is to evaluate the applicability of the 3D model obtained through Structure-from-Motion (SFM) from unmanned aerial vehicle (UAV) imagery, in order to characterize bioerosion patterns (i.e., cavities for roosting and nesting) caused by burrowing parrots on a cliff in Bahía Blanca, Argentina. The combined use of SFM-UAV technology was successfully applied for the 3D point cloud model reconstruction. The local point density, obtained by means of a sphere of radius equal to 0.5 m, reached a mean value of 9749, allowing to build a high-resolution model (0.013 m) for resolving fine spatial details in topography. To test the model, we compared it with another point cloud dataset which was created using a low cost do-it-yourself terrestrial laser scanner; the results showed that our georeferenced model had a good accuracy. In addition, an innovative method for the detection of the bioerosion features was implemented, through the processing of data provided by SFM like color and spatial coordinates (particularly the y coordinate). From the 3D model, we also derived topographic calculations such as slope angle and surface roughness, to get associations between the surface topography and bioerosion features.

DURIP: An Ultrafast Testbed for Comprehensive Characterization of Photonics, Electronic, and Optoelectronic Properties of Inegrated Nanophotonic Structures

DTIC Science & Technology

2017-10-14

Department of the Army position, policy or decision , unless so designated by other documentation. 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS (ES...characterization equipment to an al- ready available photonic characterization setup. The following table details of the spent budget and the list of purchased ...measure the response of a high-speed optical signal processing platform. The same architecture also can be used to charac- terize high-speed

Structural characterization of the exopolysaccharides from water kefir.

PubMed

Fels, Lea; Jakob, Frank; Vogel, Rudi F; Wefers, Daniel

2018-06-01

Water kefir is a beverage which is produced by initiating fermentation of a fruit extract/sucrose solution with insoluble kefir grains. Exopolysaccharides that are formed from sucrose play a major role in the kefir grain formation, but the exopolysaccharides in the kefir beverage and the detailed structural composition of the whole kefir grains have not been studied yet. Therefore, kefir grains and the corresponding kefir beverage were analyzed for exopolysaccharides by multiple chromatographic approaches and two-dimensional NMR spectroscopy. Furthermore, different fractionation techniques were applied to obtain further information about the exopolysaccharides. The exopolysaccharide-fraction of the investigated kefir beverage was predominantly composed of O3- and O2-branched dextrans as well as lower amounts of levans. The insoluble dextrans from the kefir grains were mostly O3-branched and contained an elevated portion of 1,3-linked glucose units compared to the soluble dextrans. The structurally different exopolysaccharides in water kefir suggest the involvement of multiple bacteria. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterization of Bifunctional Spin Labels for Investigating the Structural and Dynamic Properties of Membrane Proteins Using EPR Spectroscopy.

PubMed

Sahu, Indra D; Craig, Andrew F; Dunagum, Megan M; McCarrick, Robert M; Lorigan, Gary A

2017-10-05

Site-directed spin labeling (SDSL) coupled with electron paramagnetic resonance (EPR) spectroscopy is a very powerful technique to study structural and dynamic properties of membrane proteins. The most widely used spin label is methanthiosulfonate (MTSL). However, the flexibility of this spin label introduces greater uncertainties in EPR measurements obtained for determining structures, side-chain dynamics, and backbone motion of membrane protein systems. Recently, a newer bifunctional spin label (BSL), 3,4-bis(methanethiosulfonylmethyl)-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrol-1-yloxy, has been introduced to overcome the dynamic limitations associated with the MTSL spin label and has been invaluable in determining protein backbone dynamics and inter-residue distances due to its restricted internal motion and fewer size restrictions. While BSL has been successful in providing more accurate information about the structure and dynamics of several proteins, a detailed characterization of the spin label is still lacking. In this study, we characterized BSLs by performing CW-EPR spectral line shape analysis as a function of temperature on spin-labeled sites inside and outside of the membrane for the integral membrane protein KCNE1 in POPC/POPG lipid bilayers and POPC/POPG lipodisq nanoparticles. The experimental data revealed a powder pattern spectral line shape for all of the KCNE1-BSL samples at 296 K, suggesting the motion of BSLs approaches the rigid limit regime for these series of samples. BSLs were further utilized to report for the first time the distance measurement between two BSLs attached on an integral membrane protein KCNE1 in POPC/POPG lipid bilayers at room temperature using dipolar line broadening CW-EPR spectroscopy. The CW dipolar line broadening EPR data revealed a 15 ± 2 Å distance between doubly attached BSLs on KCNE1 (53/57-63/67) which is consistent with molecular dynamics modeling and the solution NMR structure of KCNE1 which yielded a

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen.

PubMed

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy.

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen

PubMed Central

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

Background The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. Objective To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Methods Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Results Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Conclusion Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy. PMID:27548813

Combined Approach for the Structural Characterization of Alkali Fluoroscandates: Solid-State NMR, Powder X-ray Diffraction, and Density Functional Theory Calculations.

PubMed

Rakhmatullin, Aydar; Polovov, Ilya B; Maltsev, Dmitry; Allix, Mathieu; Volkovich, Vladimir; Chukin, Andrey V; Boča, Miroslav; Bessada, Catherine

2018-02-05

The structures of several fluoroscandate compounds are presented here using a characterization approach combining powder X-ray diffraction and solid-state NMR. The structure of K 5 Sc 3 F 14 was fully determined from Rietveld refinement performed on powder X-ray diffraction data. Moreover, the local structures of NaScF 4 , Li 3 ScF 6 , KSc 2 F 7 , and Na 3 ScF 6 compounds were studied in detail from solid-state 19 F and 45 Sc NMR experiments. The 45 Sc chemical shift ranges for six- and seven-coordinated scandium environments were defined. The 19 F chemical shift ranges for bridging and terminal fluorine atoms were also determined. First-principles calculations of the 19 F and 45 Sc NMR parameters were carried out using plane-wave basis sets and periodic boundary conditions (CASTEP), and the results were compared with the experimental data. A good agreement between the calculated shielding constants and experimental chemical shifts was obtained. This demonstrates the good potential of computational methods in spectroscopic assignments of solid-state 45 Sc NMR spectroscopy.

Quantum chemical characterization of N-(2-hydroxybenzylidene)acetohydrazide (HBAH): a detailed vibrational and NLO analysis.

PubMed

Tamer, Ömer; Avcı, Davut; Atalay, Yusuf

2014-01-03

The molecular modeling of N-(2-hydroxybenzylidene)acetohydrazide (HBAH) was carried out using B3LYP, CAMB3LYP and PBE1PBE levels of density functional theory (DFT). The molecular structure of HBAH was solved by means of IR, NMR and UV-vis spectroscopies. In order to find the stable conformers, conformational analysis was performed based on B3LYP level. A detailed vibrational analysis was made on the basis of potential energy distribution (PED). HOMO and LUMO energies were calculated, and the obtained energies displayed that charge transfer occurs in HBAH. NLO analysis indicated that HBAH can be used as an effective NLO material. NBO analysis also proved that charge transfer, conjugative interactions and intramolecular hydrogen bonding interactions occur through HBAH. Additionally, major contributions from molecular orbitals to the electronic transitions were investigated theoretically. Copyright © 2013 Elsevier B.V. All rights reserved.

Characterization of Imposed Ordered Structures in MDPX

NASA Astrophysics Data System (ADS)

Hall, Taylor; Thomas, Edward; Konopka, Uwe; Merlino, Robert; Rosenberg, Marlene

2016-10-01

It is well understood that the microparticles in complex, or dusty, plasmas will form self-consistent crystalline patterns at the proper plasma parameters. In the Magnetized Dusty Plasma Experiment (MDPX) device, studies have been made of imposed, ordered structuring of the dust particles to a two dimensional grid. At high magnetic field (B >1 Tesla), the dust particles are shown to become spatially oriented to the structure of a wire mesh embedded in an electrically floating, upper electrode while the particles are suspended in a plasma that is generated by the powered, lower electrode in the experiment. With even higher magnetic field (B >2 Tesla), the particles become strongly confined to the mesh pattern with the particles constrained to a quasi-discreet motion that closely follows the mesh pattern. This presentation characterizes the structure of the potential energy well in which the dust particles are trapped through observation of particle motion and measurement of the thermal properties of the particles. This work is supported by funding from the U. S. Department of Energy Grant Number DE - SC0010485 and the NASA/Jet Propulsion Laboratory, JPL-1543114.

Characterization of electronic structure of periodically strained graphene

DOE PAGES

Aslani, Marjan; Garner, C. Michael; Kumar, Suhas; ...

2015-11-03

We induced periodic biaxial tensile strain in polycrystalline graphene by wrapping it over a substrate with repeating pillar-like structures with a periodicity of 600 nm. Using Raman spectroscopy, we determined to have introduced biaxial strains in graphene in the range of 0.4% to 0.7%. Its band structure was characterized using photoemission from valance bands, shifts in the secondary electron emission, and x-ray absorption from the carbon 1s levels to the unoccupied graphene conduction bands. It was observed that relative to unstrained graphene, strained graphene had a higher work function and higher density of states in the valence and conduction bands.more » Furthermore, we measured the conductivity of the strained and unstrained graphene in response to a gate voltage and correlated the changes in their behavior to the changes in the electronic structure. From these sets of data, we propose a simple band diagram representing graphene with periodic biaxial strain.« less

Optical fiber sensors for materials and structures characterization

NASA Technical Reports Server (NTRS)

Lindner, D. K.; Claus, R. O.

1991-01-01

The final technical report on Optical Fiber Sensors for Materials and Structures Characterization, covering the period August 1990 through August 1991 is presented. Research programs in the following technical areas are described; sapphire optical fiber sensors; vibration analysis using two-mode elliptical core fibers and sensors; extrinsic Fabry-Perot interferometer development; and coatings for fluorescent-based sensor. Research progress in each of these areas was substantial, as evidenced by the technical publications which are included as appendices.

Synthesis and structural characterization of oaklin-catechins.

PubMed

Sousa, André; Fernandes, Ana; Mateus, Nuno; De Freitas, Victor

2012-02-15

Condensation reactions of procyanidin dimer B4 with two representative oak wood cinnamic aldehydes (coniferaldehyde and sinapaldehyde) were conducted in winelike model solutions. Coniferaldehyde led to the formation of guaiacylcatechin-pyrylium-catechin (GCP-catechin, 737 m/z), whereas sinapaldehyde led to the formation of syringylcatechin-pyrylium-catechin (SCP-catechin, 767 m/z). The former was also structurally characterized by 1D and 2D NMR, allowing an elucidation of the formation mechanism of these oaklin-catechin adducts and demonstrating the importance of procyanidins in the formation of colored compounds through the reaction with cinnamic aldehydes extracted from oaks during storage.

Nondestructive techniques for characterizing mechanical properties of structural materials: An overview

NASA Technical Reports Server (NTRS)

Vary, A.; Klima, S. J.

1985-01-01

An overview of nondestructive evaluation (NDE) is presented to indicate the availability and application potentials of techniques for quantitative characterization of the mechanical properties of structural materials. The purpose is to review NDE techniques that go beyond the usual emphasis on flaw detection and characterization. Discussed are current and emerging NDE techniques that can verify and monitor entrinsic properties (e.g., tensile, shear, and yield strengths; fracture toughness, hardness, ductility; elastic moduli) and underlying microstructural and morphological factors. Most of the techniques described are, at present, neither widely applied nor widely accepted in commerce and industry because they are still emerging from the laboratory. The limitations of the techniques may be overcome by advances in applications research and instrumentation technology and perhaps by accommodations for their use in the design of structural parts.

A new debate for Turkish physicians: e-detailing.

PubMed

Ventura, Keti; Baybars, Miray; Dedeoglu, Ayla Ozhan

2012-01-01

The study presents an empirical analysis of the attitudes of Turkish physicians towards e-detailing practices compared to face-to-face detailing. The findings reveal that although physicians have positive attitudes toward e-detailing, on some points they are still undecided and/or have doubts. The structural model revealed that affect, convenience, and informative content influence their attitude in a positive manner, whereas the personal interaction was found to be a negative factor. Physicians' age and frequency of calls received from representatives are moderators. The present study can be seen as an addition to pharmaceutical marketing, an underresearched study field in Turkey, and e-detailing particularly.

Structural Feature Ions for Distinguishing N- and O-Linked Glycan Isomers by LC-ESI-IT MS/MS

NASA Astrophysics Data System (ADS)

Everest-Dass, Arun V.; Abrahams, Jodie L.; Kolarich, Daniel; Packer, Nicolle H.; Campbell, Matthew P.

2013-06-01

Glycomics is the comprehensive study of glycan expression in an organism, cell, or tissue that relies on effective analytical technologies to understand glycan structure-function relationships. Owing to the macro- and micro-heterogeneity of oligosaccharides, detailed structure characterization has required an orthogonal approach, such as a combination of specific exoglycosidase digestions, LC-MS/MS, and the development of bioinformatic resources to comprehensively profile a complex biological sample. Liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS/MS) has emerged as a key tool in the structural analysis of oligosaccharides because of its high sensitivity, resolution, and robustness. Here, we present a strategy that uses LC-ESI-MS/MS to characterize over 200 N- and O-glycans from human saliva glycoproteins, complemented by sequential exoglycosidase treatment, to further verify the annotated glycan structures. Fragment-specific substructure diagnostic ions were collated from an extensive screen of the literature available on the detailed structural characterization of oligosaccharides and, together with other specific glycan structure feature ions derived from cross-ring and glycosidic-linkage fragmentation, were used to characterize the glycans and differentiate isomers. The availability of such annotated mass spectrometric fragmentation spectral libraries of glycan structures, together with such substructure diagnostic ions, will be key inputs for the future development of the automated elucidation of oligosaccharide structures from MS/MS data.

Comparison of structural response and fatigue endurance of aircraft flap-like box structures subjected to acoustic loading

NASA Astrophysics Data System (ADS)

Xiao, Y.; White, R. G.; Aglietti, G. S.

2005-05-01

The results of an extensive test program to characterize the behavior of typical aircraft structures under acoustic loading and to establish their fatigue endurance are presented. The structures tested were the three flap-like box-type of structures. Each structure consisted of one flat (bottom) and one curved (top) stiffener stiffened skin panel, front, and rear spars, and ribs that divided the structures into three bays. The three structures, constructed from three different materials (aircraft standard aluminum alloy, Carbon Fibre Reinforced Plastic, and a Glass Fibre Metal Laminate, i.e., GLARE) had the same size and configuration, with only minor differences due to the use of different materials. A first set of acoustic tests with excitations of intensity ranging from 140 to 160 dB were carried out to obtain detailed data on the dynamic response of the three structures. The FE analysis of the structures is also briefly described and the results compared with the experimental data. The fatigue endurance of the structures was then determined using random acoustic excitation with an overall sound pressure level of 161 dB, and details of crack propagation are reported. .

Synthesis, characterization and crystal structure of a 1D thiocyanato bridged [Cu(en)2Zn(NCS)4]ṡH2O. Comparison of the three structures with the same [Cu(en)2Zn(NCS)4] unit - different in structural terms

NASA Astrophysics Data System (ADS)

Wrzeszcz, Grzegorz; Muzioł, Tadeusz M.; Tereba, Natalia

2015-03-01

In this paper we report the synthesis method and the structure of a one-dimensional thiocyanato bridged heterometallic compound, [Cu(en)2Zn(NCS)4]ṡH2O (1). Moreover, we compare the structure of (1) with the previously described structures of [Cu(en)2Zn(NCS)4]ṡ0.5H2O (2) and [Cu(en)2Zn(NCS)4]ṡCH3CN (3) Pryma et al. (2003) [7]. The compound (1) has been characterized by thermal decomposition, IR, Vis and EPR spectra, and magnetic studies. Structure has been determined by X-ray analysis. Described coordination polymer crystallizes in the orthorhombic Cmcm space group with a = 12.414(2), b = 10.3276(14), c = 14.967(2) Å, α = β = γ = 90°, V = 1918.8(5) Å3 and Z = 4. Each distorted tetrahedral zinc(II) centre (with N-bonded NCS-) links two tetragonally distorted octahedral copper(II) centres by two end-to-end thiocyanato bridges and vice versa forming a zigzag type of CuZn chain. The structures of (1), (2) and (3) differ in crystallographic system, space group and/or CuZn chain type as well as in details. Variable temperature magnetic susceptibility measurements show very weak antiferromagnetic interactions between the paramagnetic copper(II) ions for compound (1).

Structural and Functional Characterization of a Caenorhabditis elegans Genetic Interaction Network within Pathways

PubMed Central

Boucher, Benjamin; Lee, Anna Y.; Hallett, Michael; Jenna, Sarah

2016-01-01

A genetic interaction (GI) is defined when the mutation of one gene modifies the phenotypic expression associated with the mutation of a second gene. Genome-wide efforts to map GIs in yeast revealed structural and functional properties of a GI network. This provided insights into the mechanisms underlying the robustness of yeast to genetic and environmental insults, and also into the link existing between genotype and phenotype. While a significant conservation of GIs and GI network structure has been reported between distant yeast species, such a conservation is not clear between unicellular and multicellular organisms. Structural and functional characterization of a GI network in these latter organisms is consequently of high interest. In this study, we present an in-depth characterization of ~1.5K GIs in the nematode Caenorhabditis elegans. We identify and characterize six distinct classes of GIs by examining a wide-range of structural and functional properties of genes and network, including co-expression, phenotypical manifestations, relationship with protein-protein interaction dense subnetworks (PDS) and pathways, molecular and biological functions, gene essentiality and pleiotropy. Our study shows that GI classes link genes within pathways and display distinctive properties, specifically towards PDS. It suggests a model in which pathways are composed of PDS-centric and PDS-independent GIs coordinating molecular machines through two specific classes of GIs involving pleiotropic and non-pleiotropic connectors. Our study provides the first in-depth characterization of a GI network within pathways of a multicellular organism. It also suggests a model to understand better how GIs control system robustness and evolution. PMID:26871911

Advances and unresolved challenges in the structural characterization of isomeric lipids.

PubMed

Hancock, Sarah E; Poad, Berwyck L J; Batarseh, Amani; Abbott, Sarah K; Mitchell, Todd W

2017-05-01

As the field of lipidomics grows and its application becomes wide and varied it is important that we don't forget its foundation, i.e. the identification and measurement of molecular lipids. Advances in liquid chromatography and the emergence of ion mobility as a useful tool in lipid analysis are allowing greater separation of lipid isomers than ever before. At the same time, novel ion activation techniques, such as ozone-induced dissociation, are pushing lipid structural characterization by mass spectrometry to new levels. Nevertheless, the quantitative capacity of these techniques is yet to be proven and further refinements are required to unravel the high level of lipid complexity found in biological samples. At present there is no one technique capable of providing full structural characterization of lipids from a biological sample. There are however, numerous techniques now available (as discussed in this review) that could be deployed in a targeted approach. Moving forward, the combination of advanced separation and ion activation techniques is likely to provide mass spectrometry-based lipidomics with its best opportunity to achieve complete molecular-level lipid characterization and measurement from complex mixtures. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Detailed fault structure of the 2000 Western Tottori, Japan, earthquake sequence

USGS Publications Warehouse

Fukuyama, E.; Ellsworth, W.L.; Waldhauser, F.; Kubo, A.

2003-01-01

We investigate the faulting process of the aftershock region of the 2000 western Tottori earthquake (Mw 6.6) by combining aftershock hypocenters and moment tensor solutions. Aftershock locations were precisely determined by the double difference method using P- and S-phase arrival data of the Japan Meteorological Agency unified catalog. By combining the relocated hypocenters and moment tensor solutions of aftershocks by broadband waveform inversion of FREESIA (F-net), we successfully resolved very detailed fault structures activated by the mainshock. The estimated fault model resolves 15 individual fault segments that are consistent with both aftershock distribution and focal mechanism solutions. Rupture in the mainshock was principally confined to the three fault elements in the southern half of the zone, which is also where the earliest aftershocks concentrate. With time, the northern part of the zone becomes activated, which is also reflected in the postseismic deformation field. From the stress tensor analysis of aftershock focal mechanisms, we found a rather uniform stress field in the aftershock region, although fault strikes were scattered. The maximum stress direction is N107??E, which is consistent with the tectonic stress field in this region. In the northern part of the fault, where no slip occurred during the mainshock but postseismic slip was observed, the maximum stress direction of N130??E was possible as an alternative solution of stress tensor inversion.

Occupation Competency Profile: Steel Detailer Program.

ERIC Educational Resources Information Center

Alberta Learning, Edmonton. Apprenticeship and Industry Training.

This document presents information about the apprenticeship training program of Alberta, Canada, in general and the steel detailer program in particular. The first part of the document discusses the following items: Alberta's apprenticeship and industry training system; the apprenticeship and industry training committee structure; local…

Non-destructive testing for the structures and civil infrastructures characterization

NASA Astrophysics Data System (ADS)

Capozzoli, L.; Rizzo, E.

2012-04-01

This work evaluates the ability of non-conventional NDT techniques such as GPR, geoelectrical method and conventional ones such as infrared thermography (IRT) and sonic test for the characterization of building structures in laboratory and in-situ. Moreover, the integration of the different techniques were evaluated in order to reduce the degree of uncertainties associated. The presence of electromagnetic, resistivity or thermal anomalies in the behavior may be related to the presence of defects, crack, decay or moisture. The research was conducted in two phases: the first phase was performed in laboratory and the second one mainly in the field work. The laboratory experiments proceeded to calibrate the geophysical techniques GPR and geoelectrical method on building structures. A multi-layer structure was reconstructed in laboratory, in order to simulate a back-bridge: asphalt, reinforced concrete, sand and gravel layers. In the deep sandy layer, PVC, aluminum and steel pipes were introduced. This structure has also been brought to crack in a predetermined area and hidden internal fractures were investigated. GPR has allowed to characterize the panel in a non-invasive mode; radar maps were developed using various algorithms during post-process about 2D maps and 3D models with aerial acquisition of 400 MHz, 900MHz, 1500MHz, 2000MHz. Geoelectrical testing was performed with a network of 25 electrodes spaced at mutual distance of 5 cm. Two different configurations were used dipole-dipole and pole-dipole approaches. In the second phase, we proceeded to the analysis of pre-tensioned concrete in order to detect the possible presence of criticality in the structure. For this purpose by GPR 2GHz antenna, a '70 years precast bridge characterized by a high state of decay was studied; then were also analyzed a pillar and a beam of recent production directly into the processing plant. Moreover, results obtained using GPR were compared with those obtained through the use of

Exploring the Details of Intermolecular Interactions via a Systematic Characterization of the Structures of the Bimolecular Heterodimers Formed Between Protic Acids and Haloethylenes

NASA Astrophysics Data System (ADS)

Leung, Helen O.

2017-06-01

In the early 2000's, the work of Cole and Legon, combined with that done earlier by Kisiel, Fowler, and Legon, demonstrated that comparisons among the complexes of HF, HCl, and HCCH each with vinyl fluoride could provide information concerning the strength of intermolecular interactions. Specifically, that the length of the hydrogen bond and its deviation from linearity as a result of a secondary interaction with the nucleophilic portion of the protic acid could be correlated with the hydrogen bond strength. Building on this foundation, we undertook a systematic characterization of the molecular structures of complexes formed between these three acids and the remaining polar fluoroethylenes, seeking to unravel the nature of their intermolecular interactions. What started out as a simple confirmation of chemical intuition regarding relative interaction strengths developed into a fuller appreciation of the competition between electrostatic and steric forces in determining the lowest energy configuration for the heterodimer. Additional surprises were in store for us as we expanded the study to chlorofluoroethylenes. Although the first few examples again served to confirm earlier conclusions, subsequent complexes provided unexpected results that signaled an increasing importance of the dispersion interaction in determining the geometry of the complex as well as the fundamental differences in the electron distributions surrounding the halogens in a C-F versus C-Cl bond. Our work with these species has not only allowed us to investigate fundamental questions regarding intermolecular interactions, but obtaining and analyzing the spectra of these complexes along with those of the various haloethylene monomers and their complexes with the argon atom have provided an introduction to molecular spectroscopy and structure determination for many undergraduate students. G.C. Cole and A.C. Legon, Chem. Phys. Lett. 369, 31-40 (2003). G.C. Cole and A.C. Legon, Chem. Phys. Lett. 400

Screening concepts, characterization and structural analysis of microbial-derived bioactive lipopeptides: a review.

PubMed

Biniarz, Piotr; Łukaszewicz, Marcin; Janek, Tomasz

2017-05-01

Lipopeptide biosurfactants are surface active biomolecules that are produced by a variety of microorganisms. Microbial lipopeptides have gained the interest of microbiologists, chemists and biochemists for their high biodiversity as well as efficient action, low toxicity and good biodegradability in comparison to synthetic counterparts. In this report, we review methods for the production, isolation and screening, purification and structural characterization of microbial lipopeptides. Several techniques are currently available for each step, and we describe the most commonly utilized and recently developed techniques in this review. Investigations on lipopeptide biosurfactants in natural products require efficient isolation techniques for the characterization and evaluation of chemical and biological properties. A combination of chromatographic and spectroscopic techniques offer opportunities for a better characterization of lipopeptide structures, which in turn can lead to the application of lipopeptides in food, pharmaceutical, cosmetics, agricultural and bioremediation industries.

Concept Definition Study for In-Space Structural Characterization of a Lightweight Solar Array

NASA Technical Reports Server (NTRS)

Woods-Vedeler, Jessica A.; Pappa, Richard S.; Jones, Thomas W.; Spellman, Regina; Scott, Willis; Mockensturm, Eric M.; Liddle, Donn; Oshel, Ed; Snyder, Michael

2002-01-01

A Concept Definition Study (CDS) was conducted to develop a proposed "Lightweight High-Voltage Stretched-Lens Concentrator Solar Array Experiment" under NASA's New Millennium Program Space Technology-6 (NMP ST-6) activity. As part of a multi-organizational team, NASA Langley Research Center's role in this proposed experiment was to lead Structural Characterization of the solar array during the flight experiment. In support of this role, NASA LaRC participated in the CDS to de.ne an experiment for static, dynamic, and deployment characterization of the array. In this study, NASA LaRC traded state-of-the-art measurement approaches appropriate for an in-space, STS-based flight experiment, provided initial analysis and testing of the lightweight solar array and lens elements, performed a lighting and photogrammetric simulation in conjunction with JSC, and produced an experiment concept definition to meet structural characterization requirements.

Structural dynamics of tropical moist forest gaps

Treesearch

Maria O. Hunter; Michael Keller; Douglas Morton; Bruce Cook; Michael Lefsky; Mark Ducey; Scott Saleska; Raimundo Cosme de Oliveira; Juliana Schietti

2015-01-01

Gap phase dynamics are the dominant mode of forest turnover in tropical forests. However, gap processes are infrequently studied at the landscape scale. Airborne lidar data offer detailed information on three-dimensional forest structure, providing a means to characterize fine-scale (1 m) processes in tropical forests over large areas. Lidar-based estimates of forest...

Influences on physicians' adoption of electronic detailing (e-detailing).

PubMed

Alkhateeb, Fadi M; Doucette, William R

2009-01-01

E-detailing means using digital technology: internet, video conferencing and interactive voice response. There are two types of e-detailing: interactive (virtual) and video. Currently, little is known about what factors influence physicians' adoption of e-detailing. The objectives of this study were to test a model of physicians' adoption of e-detailing and to describe physicians using e-detailing. A mail survey was sent to a random sample of 2000 physicians practicing in Iowa. Binomial logistic regression was used to test the model of influences on physician adoption of e-detailing. On the basis of Rogers' model of adoption, the independent variables included relative advantage, compatibility, complexity, peer influence, attitudes, years in practice, presence of restrictive access to traditional detailing, type of specialty, academic affiliation, type of practice setting and control variables. A total of 671 responses were received giving a response rate of 34.7%. A total of 141 physicians (21.0%) reported using of e-detailing. The overall adoption model for using either type of e-detailing was found to be significant. Relative advantage, peer influence, attitudes, type of specialty, presence of restrictive access and years of practice had significant influences on physician adoption of e-detailing. The model of adoption of innovation is useful to explain physicians' adoption of e-detailing.

Modified ferrite core-shell nanoparticles magneto-structural characterization

NASA Astrophysics Data System (ADS)

Klekotka, Urszula; Piotrowska, Beata; Satuła, Dariusz; Kalska-Szostko, Beata

2018-06-01

In this study, ferrite nanoparticles with core-shell structures and different chemical compositions of both the core and shell were prepared with success. Proposed nanoparticles have in the first and second series magnetite core, and the shell is composed of a mixture of ferrites with Fe3+, Fe2+ and M ions (where M = Co2+, Mn2+ or Ni2+) with a general composition of M0.5Fe2.5O4. In the third series, the composition is inverted, the core is composed of a mixture of ferrites and as a shell magnetite is placed. Morphology and structural characterization of nanoparticles were done using Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), and Infrared spectroscopy (IR). While room temperature magnetic properties were measured using Mössbauer spectroscopy (MS). It is seen from Mössbauer measurements that Co always increases hyperfine magnetic field on Fe atoms at RT, while Ni and Mn have opposite influences in comparison to pure Fe ferrite, regardless of the nanoparticles structure.

Pre- and Post-Processing Tools to Create and Characterize Particle-Based Composite Model Structures

DTIC Science & Technology

2017-11-01

ARL-TR-8213 ● NOV 2017 US Army Research Laboratory Pre- and Post -Processing Tools to Create and Characterize Particle-Based...ARL-TR-8213 ● NOV 2017 US Army Research Laboratory Pre- and Post -Processing Tools to Create and Characterize Particle-Based Composite...AND SUBTITLE Pre- and Post -Processing Tools to Create and Characterize Particle-Based Composite Model Structures 5a. CONTRACT NUMBER 5b. GRANT

Computational Characterization of Electromagnetic Field Propagation in Complex Structures

DTIC Science & Technology

1998-04-10

34Computational characterization of electromagnetic field propagation in complex structures", DAAH01-91-D-ROOS D.O. 59. Dr. Michael Scalora performed the...Development, and Engineering Center, Bldg. 7804, Room 242 Redstone Arsenal, Alabama 35898-5248 USA Dr. Michael Scalora Quantum Optics Group Tel:(205...scheduled to appear. They are: (1) M. Scalora , J.P. Dowling, A.S. Manka, CM. Bowden, and J.W. Haus, Pulse Propagation Near Highly Reflective

Chord Splicing & Joining Detail; Chord & CrossBracing Joint Details; ...

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

Chord Splicing & Joining Detail; Chord & Cross-Bracing Joint Details; Cross Bracing Center Joint Detail; Chord & Diagonal Joint Detail - Vermont Covered Bridge, Highland Park, spanning Kokomo Creek at West end of Deffenbaugh Street (moved to), Kokomo, Howard County, IN

Undefined freeform surfaces having deterministic structure: issues of their characterization for functionality and manufacture

NASA Astrophysics Data System (ADS)

Whitehouse, David J.

2016-09-01

There is an increasing use of surfaces which have structure, an increase in the use of freeform surfaces, and most importantly an increase in the number of surfaces having both characteristics. These can be called multi-function surfaces, where more than one function is helped by the geometrical features: the structure can help one, the freeform another. Alternatively, they can be complementary to optimize a single function, but in all cases both geometries are involved. This paper examines some of the problems posed by having such disparate geometries on one surface; in particular, the methods of characterization needed to help understand the functionality and also to some extent their manufacture. This involves investigating ways of expressing how local and global geometric features of undefined freeform surfaces might influence function and how surface structure on top of or in series with the freeform affects the nature of the characterization. Some methods have been found of identifying possible strategies for tackling the characterization problem, based in part on the principles of least action and on the way that nature has solved the marriage of flexible freeform geometry and structure on surfaces.

Structural characterization of oxidized titanium surfaces

NASA Astrophysics Data System (ADS)

Jobin, M.; Taborelli, M.; Descouts, P.

1995-05-01

Oxidized titanium surfaces resulting from various processes have been structurally characterized by means of scanning force microscopy, x-ray photoemission spectroscopy (XPS), x-ray diffraction, and electron energy-loss spectroscopy (EELS) with losses in the 0-100 eV range. It has been found that the surface morphology has a granular structure for electropolished titanium and for titanium evaporated on mica at low substrate temperature (570 K), but changes to flat terraces for the films evaporated at higher temperature (770 K). Angular-dependent XPS has revealed the presence of a Ti2O3 suboxide at the Ti/TiO2 interface for electropolished titanium. Dry oxidation has been performed at 770 and 970 K on both weakly and highly crystallized evaporated titanium films oriented along (0001). In the case of underlying crystallized metallic titanium, the resulting TiO2 films are crystallized with the anatase (004) orientation for oxidation at 770 K and with rutile (200) orientation for oxidation at 970 K. EELS spectra interpreted in terms of the molecular orbitals of a (TiO6)8- cluster show that the local octahedral environment of titanium atoms is preserved on native oxides, even if these oxides are not crystallized.

Structurally detailed coarse-grained model for Sec-facilitated co-translational protein translocation and membrane integration

PubMed Central

Miller, Thomas F.

2017-01-01

We present a coarse-grained simulation model that is capable of simulating the minute-timescale dynamics of protein translocation and membrane integration via the Sec translocon, while retaining sufficient chemical and structural detail to capture many of the sequence-specific interactions that drive these processes. The model includes accurate geometric representations of the ribosome and Sec translocon, obtained directly from experimental structures, and interactions parameterized from nearly 200 μs of residue-based coarse-grained molecular dynamics simulations. A protocol for mapping amino-acid sequences to coarse-grained beads enables the direct simulation of trajectories for the co-translational insertion of arbitrary polypeptide sequences into the Sec translocon. The model reproduces experimentally observed features of membrane protein integration, including the efficiency with which polypeptide domains integrate into the membrane, the variation in integration efficiency upon single amino-acid mutations, and the orientation of transmembrane domains. The central advantage of the model is that it connects sequence-level protein features to biological observables and timescales, enabling direct simulation for the mechanistic analysis of co-translational integration and for the engineering of membrane proteins with enhanced membrane integration efficiency. PMID:28328943

Solid state NMR: The essential technology for helical membrane protein structural characterization

PubMed Central

Cross, Timothy A.; Ekanayake, Vindana; Paulino, Joana; Wright, Anna

2014-01-01

NMR spectroscopy of helical membrane proteins has been very challenging on multiple fronts. The expression and purification of these proteins while maintaining functionality has consumed countless graduate student hours. Sample preparations have depended on whether solution or solid-state NMR spectroscopy was to be performed – neither have been easy. In recent years it has become increasingly apparent that membrane mimic environments influence the structural result. Indeed, in these recent years we have rediscovered that Nobel laureate, Christian Anfinsen, did not say that protein structure was exclusively dictated by the amino acid sequence, but rather by the sequence in a given environment (Anfinsen, 1973) [106]. The environment matters, molecular interactions with the membrane environment are significant and many examples of distorted, non-native membrane protein structures have recently been documented in the literature. However, solid-state NMR structures of helical membrane proteins in proteoliposomes and bilayers are proving to be native structures that permit a high resolution characterization of their functional states. Indeed, solid-state NMR is uniquely able to characterize helical membrane protein structures in lipid environments without detergents. Recent progress in expression, purification, reconstitution, sample preparation and in the solid-state NMR spectroscopy of both oriented samples and magic angle spinning samples has demonstrated that helical membrane protein structures can be achieved in a timely fashion. Indeed, this is a spectacular opportunity for the NMR community to have a major impact on biomedical research through the solid-state NMR spectroscopy of these proteins. PMID:24412099

Solid state NMR: The essential technology for helical membrane protein structural characterization

NASA Astrophysics Data System (ADS)

Cross, Timothy A.; Ekanayake, Vindana; Paulino, Joana; Wright, Anna

2014-02-01

NMR spectroscopy of helical membrane proteins has been very challenging on multiple fronts. The expression and purification of these proteins while maintaining functionality has consumed countless graduate student hours. Sample preparations have depended on whether solution or solid-state NMR spectroscopy was to be performed - neither have been easy. In recent years it has become increasingly apparent that membrane mimic environments influence the structural result. Indeed, in these recent years we have rediscovered that Nobel laureate, Christian Anfinsen, did not say that protein structure was exclusively dictated by the amino acid sequence, but rather by the sequence in a given environment (Anfinsen, 1973) [106]. The environment matters, molecular interactions with the membrane environment are significant and many examples of distorted, non-native membrane protein structures have recently been documented in the literature. However, solid-state NMR structures of helical membrane proteins in proteoliposomes and bilayers are proving to be native structures that permit a high resolution characterization of their functional states. Indeed, solid-state NMR is uniquely able to characterize helical membrane protein structures in lipid environments without detergents. Recent progress in expression, purification, reconstitution, sample preparation and in the solid-state NMR spectroscopy of both oriented samples and magic angle spinning samples has demonstrated that helical membrane protein structures can be achieved in a timely fashion. Indeed, this is a spectacular opportunity for the NMR community to have a major impact on biomedical research through the solid-state NMR spectroscopy of these proteins.

Characterization of Novel Thin-Films and Structures for Integrated Circuit and Photovoltaic Applications

NASA Astrophysics Data System (ADS)

Zhao, Zhao

Thin films have been widely used in various applications. This research focuses on the characterization of novel thin films in the integrated circuits and photovoltaic techniques. The ion implanted layer in silicon can be treated as ion implanted thin film, which plays an essential role in the integrated circuits fabrication. Novel rapid annealing methods, i.e. microwave annealing and laser annealing, are conducted to activate ion dopants and repair the damages, and then are compared with the conventional rapid thermal annealing (RTA). In terms of As+ and P+ implanted Si, the electrical and structural characterization confirms that the microwave and laser annealing can achieve more efficient dopant activation and recrystallization than conventional RTA. The efficient dopant activation in microwave annealing is attributed to ion hopping under microwave field, while the liquid phase growth in laser annealing provides its efficient dopant activation. The characterization of dopants diffusion shows no visible diffusion after microwave annealing, some extent of end range of diffusion after RTA, and significant dopant diffusion after laser annealing. For photovoltaic applications, an indium-free novel three-layer thin-film structure (transparent composited electrode (TCE)) is demonstrated as a promising transparent conductive electrode for solar cells. The characterization of TCE mainly focuses on its optical and electrical properties. Transfer matrix method for optical transmittance calculation is validated and proved to be a desirable method for predicting transmittance of TCE containing continuous metal layer, and can estimate the trend of transmittance as the layer thickness changes. TiO2/Ag/TiO2 (TAgT) electrode for organic solar cells (OSCs) is then designed using numerical simulation and shows much higher Haacke figure of merit than indium tin oxide (ITO). In addition, TAgT based OSC shows better performance than ITO based OSC when compatible hole transfer layer

Structural details of Al/Al 2O3 junctions and their role in the formation of electron tunnel barriers

NASA Astrophysics Data System (ADS)

Koberidze, M.; Puska, M. J.; Nieminen, R. M.

2018-05-01

We present a computational study of the adhesive and structural properties of the Al/Al 2O3 interfaces as building blocks of the metal-insulator-metal (MIM) tunnel devices, where electron transport is accomplished via tunneling mechanism through the sandwiched insulating barrier. The main goal of this paper is to understand, on the atomic scale, the role of the geometrical details in the formation of the tunnel barrier profiles. Initially, we concentrate on the adhesive properties of the interfaces. To provide reliable results, we carefully assess the accuracy of the traditional methods used to examine Al/Al 2O3 systems. These are the most widely employed exchange-correlation functionals—local-density approximation and two different generalized gradient approximations; the universal binding-energy relation for predicting equilibrium interfacial distances and adhesion energies; and the ideal work of separation as a measure of junction stability. In addition, we show that the established interpretation of the computed ideal work of separation might be misleading in predicting the optimal interface structures. Finally, we perform a detailed analysis of the atomic and interplanar relaxations in each junction, and identify their contributions to the tunnel barrier parameters. Our results imply that the structural irregularities on the surface of the Al film have a significant contribution to lowering the tunnel barrier height, while atomic relaxations at the interface and interplanar relaxations in Al2O3 may considerably change the width of the barrier and, thus, distort its uniformity. Both the effects may critically influence the performance of the MIM tunnel devices.

Measurement of protein unfolding/refolding kinetics and structural characterization of hidden intermediates by NMR relaxation dispersion

PubMed Central

Meinhold, Derrick W.; Wright, Peter E.

2011-01-01

Detailed understanding of protein function and malfunction hinges on the ability to characterize transiently populated states and the transitions between them. Here, we use 15N, , and 13CO NMR R2 relaxation dispersion to investigate spontaneous unfolding and refolding events of native apomyoglobin. Above pH 5.0, dispersion is dominated by processes involving fluctuations of the F-helix region, which is invisible in NMR spectra. Measurements of R2 dispersion for residues contacted by the F-helix region in the native (N) structure reveal a transient state formed by local unfolding of helix F and undocking from the protein core. A similar state was detected at pH 4.75–4.95 and determined to be an on-pathway intermediate (I1) in a linear three-state unfolding scheme (N⇆I1⇆MG) leading to a transiently populated molten globule (MG) state. The slowest steps in unfolding and refolding are N → I1 (36 s-1) and MG → I1 (26 s-1), respectively. Differences in chemical shift between N and I1 are very small, except in regions adjacent to helix F, showing that their core structures are similar. Chemical shift changes between the N and MG states, obtained from R2 dispersion, reveal that the transient MG state is structurally similar to the equilibrium MG observed previously at high temperature and low pH. Analysis of MG state chemical shifts shows the location of residual helical structure in the transient intermediate and identifies regions that unfold or rearrange into nonnative structure during the N → MG transition. The experiments also identify regions of energetic frustration that “crack” during unfolding and impede the refolding process. PMID:21562212

A novel embeddable spherical smart aggregate for structural health monitoring: part I. Fabrication and electrical characterization

NASA Astrophysics Data System (ADS)

Kong, Qingzhao; Fan, Shuli; Bai, Xiaolong; Mo, Y. L.; Song, Gangbing

2017-09-01

Recently developed piezoceramic-based transducers, known as smart aggregates (SAs), have shown their applicability and versatility in various applications of structural health monitoring (SHM). The lead zirconate titanate (PZT) patches embedded inside SAs have different modes that are more suitable for generating or receiving different types of stress waves (e.g. P and S waves, each of which has a unique role in SHM). However, due to the geometry of the 2D PZT patch, the embedded SA can only generate or receive the stress wave in a single direction and thus greatly limits its applications. This paper is the first of a series of two companion papers that introduces the authors’ latest work in developing a novel, embeddable spherical smart aggregate (SSA) for the health monitoring of concrete structures. In addition to the 1D guided wave produced by SA, the SSA embedded in concrete structures can generate or receive omni-directional stress waves that can significantly improve the detection aperture and provide additional functionalities in SHM. In the first paper (Part I), the detailed fabrication procedures with the help of 3D printing technology and electrical characterization of the proposed SSA is presented. The natural frequencies of the SSA were experimentally obtained and further compared with the numerical results. In addition, the influence of the components’ thickness (spherical piezoceramic shell and epoxy) and outer radius (spherical piezoceramic shell and protection concrete) on the natural frequencies of the SSA were analytically studied. The results will help elucidate the key parameters that determine the natural frequencies of the SSA. The natural frequencies of the SSA can thus be designed for suitability in the damage detection of concrete structures. In the second paper (Part II), further numerical and experimental verifications on the performance of the proposed SSA in concrete structures will be discussed.

Biochemical and Structural Characterization of the Human TL1A Ectodomain

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

Zhan, C.; Yan, Q; Patskovsky, Y

TNF-like 1A (TL1A) is a newly described member of the TNF superfamily that is directly implicated in the pathogenesis of autoimmune diseases, including inflammatory bowel disease, atherosclerosis, and rheumatoid arthritis. We report the crystal structure of the human TL1A extracellular domain at a resolution of 2.5 {angstrom}, which reveals a jelly-roll fold typical of the TNF superfamily. This structural information, in combination with complementary mutagenesis and biochemical characterization, provides insights into the binding interface and the specificity of the interactions between TL1A and the DcR3 and DR3 receptors. These studies suggest that the mode of interaction between TL1A and DcR3more » differs from other characterized TNF ligand/receptor complexes. In addition, we have generated functional TL1A mutants with altered disulfide bonding capability that exhibit enhanced solution properties, which will facilitate the production of materials for future cell-based and whole animal studies. In summary, these studies provide insights into the structure and function of TL1A and provide the basis for the rational manipulation of its interactions with cognate receptors.« less

Native top-down mass spectrometry for the structural characterization of human hemoglobin

DOE PAGES

Zhang, Jiang; Malmirchegini, G. Reza; Clubb, Robert T.; ...

2015-06-09

Native mass spectrometry (MS) has become an invaluable tool for the characterization of proteins and non-covalent protein complexes under near physiological solution conditions. Here we report the structural characterization of human hemoglobin (Hb), a 64 kDa oxygen-transporting protein complex, by high resolution native top-down mass spectrometry using electrospray ionization (ESI) and a 15-Tesla Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. Native MS preserves the non-covalent interactions between the globin subunits, and electron capture dissociation (ECD) produces fragments directly from the intact Hb complex without dissociating the subunits. Using activated ion ECD, we observe the gradual unfolding process of themore » Hb complex in the gas phase. Without protein ion activation, the native Hb shows very limited ECD fragmentation from the N-termini, suggesting a tightly packed structure of the native complex and therefore low fragmentation efficiency. Precursor ion activation allows steady increase of N-terminal fragment ions, while the C-terminal fragments remain limited (38 c ions and 4 z ions on the α chain; 36 c ions and 2 z ions on the β chain). This ECD fragmentation pattern suggests that upon activation, the Hb complex starts to unfold from the N-termini of both subunits, whereas the C-terminal regions and therefore the potential regions involved in the subunit binding interactions remain intact. ECD-MS of the Hb dimer show similar fragmentation patterns as the Hb tetramer, providing further evidence for the hypothesized unfolding process of the Hb complex in the gas phase. Native top-down ECD-MS allows efficient probing of the Hb complex structure and the subunit binding interactions in the gas phase. Finally, it may provide a fast and effective means to probe the structure of novel protein complexes that are intractable to traditional structural characterization tools.« less

Characterization of Low-Molecular-Weight Heparins by Strong Anion-Exchange Chromatography.

PubMed

Sadowski, Radosław; Gadzała-Kopciuch, Renata; Kowalkowski, Tomasz; Widomski, Paweł; Jujeczka, Ludwik; Buszewski, Bogusław

2017-11-01

Currently, detailed structural characterization of low-molecular-weight heparin (LMWH) products is an analytical subject of great interest. In this work, we carried out a comprehensive structural analysis of LMWHs and applied a modified pharmacopeial method, as well as methods developed by other researchers, to the analysis of novel biosimilar LMWH products; and, for the first time, compared the qualitative and quantitative composition of commercially available drugs (enoxaparin, nadroparin, and dalteparin). For this purpose, we used strong anion-exchange (SAX) chromatography with spectrophotometric detection because this method is more helpful, easier, and faster than other separation techniques for the detailed disaccharide analysis of new LMWH drugs. In addition, we subjected the obtained results to statistical analysis (factor analysis, t-test, and Newman-Keuls post hoc test).

Synthesis and structural characterization of bulk Sb2Te3 single crystal

NASA Astrophysics Data System (ADS)

Sultana, Rabia; Gahtori, Bhasker; Meena, R. S.; Awana, V. P. S.

2018-05-01

We report the growth and characterization of bulk Sb2Te3 single crystal synthesized by the self flux method via solid state reaction route from high temperature melt (850˚C) and slow cooling (2˚C/hour) of constituent elements. The single crystal X-ray diffraction pattern showed the 00l alignment and the high crystalline nature of the resultant sample. The rietveld fitted room temperature powder XRD revealed the phase purity and rhombohedral structure of the synthesized crystal. The formation and analysis of unit cell structure further verified the rhombohedral structure composed of three quintuple layers stacked one over the other. The SEM image showed the layered directional growth of the synthesized crystal carried out using the ZEISS-EVOMA-10 scanning electron microscope The electrical resistivity measurement was carried out using the conventional four-probe method on a quantum design Physical Property Measurement System (PPMS). The temperature dependent electrical resistivity plot for studied Sb2Te3 single crystal depicts metallic behaviour in the absence of any applied magnetic field. The synthesis as well as the structural characterization of as grown Sb2Te3 single crystal is reported and discussed in the present letter.

Damping characterization in large structures

NASA Technical Reports Server (NTRS)

Eke, Fidelis O.; Eke, Estelle M.

1991-01-01

This research project has as its main goal the development of methods for selecting the damping characteristics of components of a large structure or multibody system, in such a way as to produce some desired system damping characteristics. The main need for such an analytical device is in the simulation of the dynamics of multibody systems consisting, at least partially, of flexible components. The reason for this need is that all existing simulation codes for multibody systems require component-by-component characterization of complex systems, whereas requirements (including damping) often appear at the overall system level. The main goal was met in large part by the development of a method that will in fact synthesize component damping matrices from a given system damping matrix. The restrictions to the method are that the desired system damping matrix must be diagonal (which is almost always the case) and that interbody connections must be by simple hinges. In addition to the technical outcome, this project contributed positively to the educational and research infrastructure of Tuskegee University - a Historically Black Institution.

A global/local analysis method for treating details in structural design

NASA Technical Reports Server (NTRS)

Aminpour, Mohammad A.; Mccleary, Susan L.; Ransom, Jonathan B.

1993-01-01

A method for analyzing global/local behavior of plate and shell structures is described. In this approach, a detailed finite element model of the local region is incorporated within a coarser global finite element model. The local model need not be nodally compatible (i.e., need not have a one-to-one nodal correspondence) with the global model at their common boundary; therefore, the two models may be constructed independently. The nodal incompatibility of the models is accounted for by introducing appropriate constraint conditions into the potential energy in a hybrid variational formulation. The primary advantage of this method is that the need for transition modeling between global and local models is eliminated. Eliminating transition modeling has two benefits. First, modeling efforts are reduced since tedious and complex transitioning need not be performed. Second, errors due to the mesh distortion, often unavoidable in mesh transitioning, are minimized by avoiding distorted elements beyond what is needed to represent the geometry of the component. The method is applied reduced to a plate loaded in tension and transverse bending. The plate has a central hole, and various hole sixes and shapes are studied. The method is also applied to a composite laminated fuselage panel with a crack emanating from a window in the panel. While this method is applied herein to global/local problems, it is also applicable to the coupled analysis of independently modeled components as well as adaptive refinement.

Characterization of Capsicum annuum Genetic Diversity and Population Structure Based on Parallel Polymorphism Discovery with a 30K Unigene Pepper GeneChip

PubMed Central

Hill, Theresa A.; Ashrafi, Hamid; Reyes-Chin-Wo, Sebastian; Yao, JiQiang; Stoffel, Kevin; Truco, Maria-Jose; Kozik, Alexander; Michelmore, Richard W.; Van Deynze, Allen

2013-01-01

The widely cultivated pepper, Capsicum spp., important as a vegetable and spice crop world-wide, is one of the most diverse crops. To enhance breeding programs, a detailed characterization of Capsicum diversity including morphological, geographical and molecular data is required. Currently, molecular data characterizing Capsicum genetic diversity is limited. The development and application of high-throughput genome-wide markers in Capsicum will facilitate more detailed molecular characterization of germplasm collections, genetic relationships, and the generation of ultra-high density maps. We have developed the Pepper GeneChip® array from Affymetrix for polymorphism detection and expression analysis in Capsicum. Probes on the array were designed from 30,815 unigenes assembled from expressed sequence tags (ESTs). Our array design provides a maximum redundancy of 13 probes per base pair position allowing integration of multiple hybridization values per position to detect single position polymorphism (SPP). Hybridization of genomic DNA from 40 diverse C. annuum lines, used in breeding and research programs, and a representative from three additional cultivated species (C. frutescens, C. chinense and C. pubescens) detected 33,401 SPP markers within 13,323 unigenes. Among the C. annuum lines, 6,426 SPPs covering 3,818 unigenes were identified. An estimated three-fold reduction in diversity was detected in non-pungent compared with pungent lines, however, we were able to detect 251 highly informative markers across these C. annuum lines. In addition, an 8.7 cM region without polymorphism was detected around Pun1 in non-pungent C. annuum. An analysis of genetic relatedness and diversity using the software Structure revealed clustering of the germplasm which was confirmed with statistical support by principle components analysis (PCA) and phylogenetic analysis. This research demonstrates the effectiveness of parallel high-throughput discovery and application of genome

Characterization of Capsicum annuum genetic diversity and population structure based on parallel polymorphism discovery with a 30K unigene Pepper GeneChip.

PubMed

Hill, Theresa A; Ashrafi, Hamid; Reyes-Chin-Wo, Sebastian; Yao, JiQiang; Stoffel, Kevin; Truco, Maria-Jose; Kozik, Alexander; Michelmore, Richard W; Van Deynze, Allen

2013-01-01

The widely cultivated pepper, Capsicum spp., important as a vegetable and spice crop world-wide, is one of the most diverse crops. To enhance breeding programs, a detailed characterization of Capsicum diversity including morphological, geographical and molecular data is required. Currently, molecular data characterizing Capsicum genetic diversity is limited. The development and application of high-throughput genome-wide markers in Capsicum will facilitate more detailed molecular characterization of germplasm collections, genetic relationships, and the generation of ultra-high density maps. We have developed the Pepper GeneChip® array from Affymetrix for polymorphism detection and expression analysis in Capsicum. Probes on the array were designed from 30,815 unigenes assembled from expressed sequence tags (ESTs). Our array design provides a maximum redundancy of 13 probes per base pair position allowing integration of multiple hybridization values per position to detect single position polymorphism (SPP). Hybridization of genomic DNA from 40 diverse C. annuum lines, used in breeding and research programs, and a representative from three additional cultivated species (C. frutescens, C. chinense and C. pubescens) detected 33,401 SPP markers within 13,323 unigenes. Among the C. annuum lines, 6,426 SPPs covering 3,818 unigenes were identified. An estimated three-fold reduction in diversity was detected in non-pungent compared with pungent lines, however, we were able to detect 251 highly informative markers across these C. annuum lines. In addition, an 8.7 cM region without polymorphism was detected around Pun1 in non-pungent C. annuum. An analysis of genetic relatedness and diversity using the software Structure revealed clustering of the germplasm which was confirmed with statistical support by principle components analysis (PCA) and phylogenetic analysis. This research demonstrates the effectiveness of parallel high-throughput discovery and application of genome

Role and structural characterization of plant aldehyde dehydrogenases from family 2 and family 7.

PubMed

Končitíková, Radka; Vigouroux, Armelle; Kopečná, Martina; Andree, Tomáš; Bartoš, Jan; Šebela, Marek; Moréra, Solange; Kopečný, David

2015-05-15

Aldehyde dehydrogenases (ALDHs) are responsible for oxidation of biogenic aldehyde intermediates as well as for cell detoxification of aldehydes generated during lipid peroxidation. So far, 13 ALDH families have been described in plants. In the present study, we provide a detailed biochemical characterization of plant ALDH2 and ALDH7 families by analysing maize and pea ALDH7 (ZmALDH7 and PsALDH7) and four maize cytosolic ALDH(cALDH)2 isoforms RF2C, RF2D, RF2E and RF2F [the first maize ALDH2 was discovered as a fertility restorer (RF2A)]. We report the crystal structures of ZmALDH7, RF2C and RF2F at high resolution. The ZmALDH7 structure shows that the three conserved residues Glu(120), Arg(300) and Thr(302) in the ALDH7 family are located in the substrate-binding site and are specific to this family. Our kinetic analysis demonstrates that α-aminoadipic semialdehyde, a lysine catabolism intermediate, is the preferred substrate for plant ALDH7. In contrast, aromatic aldehydes including benzaldehyde, anisaldehyde, cinnamaldehyde, coniferaldehyde and sinapaldehyde are the best substrates for cALDH2. In line with these results, the crystal structures of RF2C and RF2F reveal that their substrate-binding sites are similar and are formed by an aromatic cluster mainly composed of phenylalanine residues and several nonpolar residues. Gene expression studies indicate that the RF2C gene, which is strongly expressed in all organs, appears essential, suggesting that the crucial role of the enzyme would certainly be linked to the cell wall formation using aldehydes from phenylpropanoid pathway as substrates. Finally, plant ALDH7 may significantly contribute to osmoprotection because it oxidizes several aminoaldehydes leading to products known as osmolytes.

Structural Characterization of Vapor-deposited Organic Glasses

NASA Astrophysics Data System (ADS)

Gujral, Ankit

Physical vapor deposition, a common route of thin film fabrication for organic electronic devices, has recently been shown to produce organic glassy films with enhanced kinetic stability and anisotropic structure. Anisotropic structures are of interest in the organic electronics community as it has been shown that certain structures lead to enhanced device performance, such as higher carrier mobility and better light outcoupling. A mechanism proposed to explain the origin of the stability and anisotropy of vapor-deposited glasses relies on two parameters: 1) enhanced molecular mobility at the free surface (vacuum interface) of a glass, and 2) anisotropic molecular packing at the free surface of the supercooled liquid of the glass-forming system. By vapor-depositing onto a substrate maintained at Tsubstrate < Tg (where Tg is the glass transition temperature), the enhanced molecular mobility at the free surface allows every molecule that lands on the surface to at least partially equilibrate to the preferred anisotropic molecular packing motifs before being buried by further deposition. The extent of equilibration depends on the mobility at the surface, controlled by Tsubstrate, and the residence time on the free surface, controlled by the rate of deposition. This body of work deals with the optimization of deposition conditions and system chemistry to prepare and characterize films with functional anisotropic structures. Here, we show that structural anisotropy can be attained for a variety of molecular systems including a rod-shaped non-mesogen, TPD, a rod-shaped smectic mesogen, itraconazole, two discotic mesogens, phenanthroperylene-ester and triphenylene-ester, and a disc-shaped non-mesogen, m-MTDATA. Experimental evidence is also provided of the anisotropic molecular packing at the free surface (vacuum interface) for the disc-shaped systems that are consistent with the expectations of the proposed mechanism and the final bulk state of the vapor

Development of thermoplastic composite aircraft structures

NASA Technical Reports Server (NTRS)

Renieri, Michael P.; Burpo, Steven J.; Roundy, Lance M.; Todd, Stephanie A.; Kim, H. J.

1992-01-01

Efforts focused on the use of thermoplastic composite materials in the development of structural details associated with an advanced fighter fuselage section with applicability to transport design. In support of these designs, mechanics developments were conducted in two areas. First, a dissipative strain energy approach to material characterization and failure prediction, developed at the Naval Research Laboratory, was evaluated as a design/analysis tool. Second, a finite element formulation for thick composites was developed and incorporated into a lug analysis method which incorporates pin bending effects. Manufacturing concepts were developed for an upper fuel cell cover. A detailed trade study produced two promising concepts: fiber placement and single-step diaphragm forming. Based on the innovative design/manufacturing concepts for the fuselage section primary structure, elements were designed, fabricated, and structurally tested. These elements focused on key issues such as thick composite lugs and low cost forming of fastenerless, stiffener/moldine concepts. Manufacturing techniques included autoclave consolidation, single diaphragm consolidation (SDCC) and roll-forming.

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

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

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Detail, Vertical Cross Bracing-End Detail - Cumberland Covered Bridge, Spanning Mississinewa River, Matthews, Grant County, IN

A Model Comparison for Characterizing Protein Motions from Structure

NASA Astrophysics Data System (ADS)

David, Charles; Jacobs, Donald

2011-10-01

A comparative study is made using three computational models that characterize native state dynamics starting from known protein structures taken from four distinct SCOP classifications. A geometrical simulation is performed, and the results are compared to the elastic network model and molecular dynamics. The essential dynamics is quantified by a direct analysis of a mode subspace constructed from ANM and a principal component analysis on both the FRODA and MD trajectories using root mean square inner product and principal angles. Relative subspace sizes and overlaps are visualized using the projection of displacement vectors on the model modes. Additionally, a mode subspace is constructed from PCA on an exemplar set of X-ray crystal structures in order to determine similarly with respect to the generated ensembles. Quantitative analysis reveals there is significant overlap across the three model subspaces and the model independent subspace. These results indicate that structure is the key determinant for native state dynamics.

Wet formation and structural characterization of quasi-hexagonal monolayers.

PubMed

Batys, Piotr; Weroński, Paweł; Nosek, Magdalena

2016-01-01

We have presented a simple and efficient method for producing dense particle monolayers with controlled surface coverage. The method is based on particle sedimentation, manipulation of the particle-substrate electrostatic interaction, and gentle mechanical vibration of the system. It allows for obtaining quasi-hexagonal structures under wet conditions. Using this method, we have produced a monolayer of 3 μm silica particles on a glassy carbon substrate. By optical microscopy, we have determined the coordinates of the particles and surface coverage of the obtained structure to be 0.82. We have characterized the monolayer structure by means of the pair-correlation function and power spectrum. We have also compared the results with those for a 2D hexagonal monolayer and monolayer generated by random sequential adsorption at the coverage 0.50. We have found the surface fractal dimension to be 2.5, independently of the monolayer surface coverage. Copyright © 2015 Elsevier Inc. All rights reserved.

Structural characterization/correlation of calorimetric properties of coal fluids: Final report, September 1, 1985--August 31, 1988

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

Starling, K.E.; Mallinson, R.G.; Li, M.H.

The objective of this research is to examine the relationship between the calorimetric properties of coal fluids and their molecular functional group composition. Coal fluid samples which have had their calorimetric properties measured are characterized using proton NMR, IR, and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal fluid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for ideal gas heat capacities are then examined withinmore » an existing equation of state methodology to determine an optimal correlation. The optimal correlation for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model is examined. 8 refs.« less

Understanding the structure of skill through a detailed analysis of Individuals' performance on the Space Fortress game.

PubMed

Towne, Tyler J; Boot, Walter R; Ericsson, K Anders

2016-09-01

In this paper we describe a novel approach to the study of individual differences in acquired skilled performance in complex laboratory tasks based on an extension of the methodology of the expert-performance approach (Ericsson & Smith, 1991) to shorter periods of training and practice. In contrast to more traditional approaches that study the average performance of groups of participants, we explored detailed behavioral changes for individual participants across their development on the Space Fortress game. We focused on dramatic individual differences in learning and skill acquisition at the individual level by analyzing the archival game data of several interesting players to uncover the specific structure of their acquired skill. Our analysis revealed that even after maximal values for game-generated subscores were reached, the most skilled participant's behaviors such as his flight path, missile firing, and mine handling continued to be refined and improved (Participant 17 from Boot et al., 2010). We contrasted this participant's behavior with the behavior of several other participants and found striking differences in the structure of their performance, which calls into question the appropriateness of averaging their data. For example, some participants engaged in different control strategies such as "world wrapping" or maintaining a finely-tuned circular flight path around the fortress (in contrast to Participant 17's angular flight path). In light of these differences, we raise fundamental questions about how skill acquisition for individual participants should be studied and described. Our data suggest that a detailed analysis of individuals' data is an essential step for generating a general theory of skill acquisition that explains improvement at the group and individual levels. Copyright © 2016 Elsevier B.V. All rights reserved.

NMR Relaxometry to Characterize the Drug Structural Phase in a Porous Construct.

PubMed

Thrane, Linn W; Berglund, Emily A; Wilking, James N; Vodak, David; Seymour, Joseph D

2018-06-14

Nuclear magnetic resonance (NMR) frequency spectra and T 2 relaxation time measurements, using a high-power radio frequency probe, are shown to characterize the presence of an amorphous drug in a porous silica construct. The results indicate the ability of non-solid-state NMR methods to characterize crystalline and amorphous solid structural phases in drugs. Two-dimensional T 1 - T 2 magnetic relaxation time correlation experiments are shown to monitor the impact of relative humidity on the drug in a porous silica tablet.

Structural characterization of sol-gel derived oxide nanostuctures using synchrotron x-ray techniques

NASA Astrophysics Data System (ADS)

Sun, Tao

Ceramic oxides possess extraordinarily rich functionalities. With the advent of nanofabrication techniques, it is now possible to grow nanostructured oxides with precise control of composition, morphology, and microstructure, which has re-vitalized the research in the field of traditional ceramics. The unexpected behavior and enhanced properties of oxide nanostructures have been extensively reported. However, knowledge about the underlying mechanisms as well as structural implications is still quite limited. Therefore, it is imperative to develop and employ sophisticated characterization tools for unraveling the structure-property relationships for oxide nanostructures. The present thesis work aims at addressing the critical issues associated with fabrication, and more importantly, structural characterization of functional oxide nanostructures. The dissertation starts with introducing the strategy for synthesizing phase-pure and highly controlled oxide nanostructures using sol-gel deposition and an innovative approach called "soft" electron beam lithography. Some specific oxides are chosen for the present study, such as BiFeO3, CoFe2O4, and SnO2, because of their scientific and technological significance. Subsequent to fabrication of tailored oxide nanostructures, advanced synchrotron x-ray scattering techniques have been applied for structural characterization. The nucleation and growth behavior of BiFeO3 thin film was investigated using in situ grazing-incidence small-angle x-ray scattering (GISAXS) technique. The results reveal that the kinetics for early-stage nuclei growth are governed by the oriented-attachment model. Moreover, the porous structures of undoped and Pd-doped semiconducting SnOx thin films were quantitatively characterized using GISAXS. By correlating the structural parameters with H2 sensitivity of SnOx films, it is found out that the microstructure of doped film is favorable for gas sensing, but it is not the major reason for the overall

Material Characterization for the Analysis of Skin/Stiffener Separation

NASA Technical Reports Server (NTRS)

Davila, Carlos G.; Leone, Frank A.; Song, Kyongchan; Ratcliffe, James G.; Rose, Cheryl A.

2017-01-01

Test results show that separation failure in co-cured skin/stiffener interfaces is characterized by dense networks of interacting cracks and crack path migrations that are not present in standard characterization tests for delamination. These crack networks result in measurable large-scale and sub-ply-scale R curve toughening mechanisms, such as fiber bridging, crack migration, and crack delving. Consequently, a number of unknown issues exist regarding the level of analysis detail that is required for sufficient predictive fidelity. The objective of the present paper is to examine some of the difficulties associated with modeling separation failure in stiffened composite structures. A procedure to characterize the interfacial material properties is proposed and the use of simplified models based on empirical interface properties is evaluated.

Structural and dynamic characterization of eukaryotic gene regulatory protein domains in solution

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

Lee, Andrew Loyd

Solution NMR was primarily used to characterize structure and dynamics in two different eukaryotic protein systems: the δ-Al-ε activation domain from c-jun and the Drosophila RNA-binding protein Sex-lethal. The second system is the Drosophila Sex-lethal (Sxl) protein, an RNA-binding protein which is the ``master switch`` in sex determination. Sxl contains two adjacent RNA-binding domains (RBDs) of the RNP consensus-type. The NMR spectrum of the second RBD (Sxl-RBD2) was assigned using multidimensional heteronuclear NMR, and an intermediate-resolution family of structures was calculated from primarily NOE distance restraints. The overall fold was determined to be similar to other RBDs: a βαβ-βαβ patternmore » of secondary structure, with the two helices packed against a 4-stranded anti-parallel β-sheet. In addition 15N T 1, T 2, and 15N/ 1H NOE relaxation measurements were carried out to characterize the backbone dynamics of Sxl-RBD2 in solution. RNA corresponding to the polypyrimidine tract of transformer pre-mRNA was generated and titrated into 3 different Sxl-RBD protein constructs. Combining Sxl-RBD1+2 (bht RBDs) with this RNA formed a specific, high affinity protein/RNA complex that is amenable to further NMR characterization. The backbone 1H, 13C, and 15N resonances of Sxl-RBD1+2 were assigned using a triple-resonance approach, and 15N relaxation experiments were carried out to characterize the backbone dynamics of this complex. The changes in chemical shift in Sxl-RBD1+2 upon binding RNA are observed using Sxl-RBD2 as a substitute for unbound Sxl-RBD1+2. This allowed the binding interface to be qualitatively mapped for the second domain.« less

Structural characterization of multimetallic nanoparticles

NASA Astrophysics Data System (ADS)

Mukundan, Vineetha

Bimetallic and trimetallic alloy nanoparticles have enhanced catalytic activities due to their unique structural properties. Using in situ time-resolved synchrotron based x-ray diffraction, we investigated the structural properties of nanoscale catalysts undergoing various heat treatments. Thermal treatment brings about changes in particle size, morphology, dispersion of metals on support, alloying, surface electronic properties, etc. First, the mechanisms of coalescence and grain growth in PtNiCo nanoparticles supported on planar silica on silicon were examined in detail in the temperature range 400-900°C. The sintering process in PtNiCo nanoparticles was found to be accompanied by lattice contraction and L10 chemical ordering. The mass transport involved in sintering is attributed to grain boundary diffusion and its corresponding activation energy is estimated from the data analysis. Nanoscale alloying and phase transformations in physical mixtures of Pd and Cu ultrafine nanoparticles were also investigated in real time with in situ synchrotron based x-ray diffraction complemented by ex situ high-resolution transmission electron microscopy. PdCu nanoparticles are interesting because they are found to be more efficient as catalysts in ethanol oxidation reaction (EOR) than monometallic Pd catalysts. The combination of metal support interaction and reactive/non-reactive environment was found to determine the thermal evolution and ultimate structure of this binary system. The composition of the as prepared Pd:Cu mixture in this study was 34% Pd and 66% Cu. At 300°C, the nanoparticles supported on silica and carbon black intermix to form a chemically ordered CsCl-type (B2) alloy phase. The B2 phase transforms into a disordered fcc alloy at higher temperature (>450°C). The alloy nanoparticles supported on silica and carbon black are homogeneous in volume, but evidence was found of Pd surface enrichment. In sharp contrast, when supported on alumina, the two metals

64. DETAIL OF CONNECTIONS FOR SIXTEEN CABLES AT THE CARRIAGE ...

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

64. DETAIL OF CONNECTIONS FOR SIXTEEN CABLES AT THE CARRIAGE SUPPORT STRUCTURE, STRUCTURE. April 20, 1948. 1048. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

Functional Properties at Domain Walls in BiFeO3: Electrical, Magnetic, and Structural investigations

NASA Astrophysics Data System (ADS)

He, Qing; Yang, C.-H.; Yu, P.; Gajek, M.; Seidel, J.; Ramesh, R.; Wang, F.; Chu, Y.-H.; Martin, L. W.; Spaldin, N.; Rother, A.

2009-03-01

BiFeO3 (BFO) is a widely studied robust ferroelectric, antiferromagnetic multiferroic. Conducting-atomic force microscopy studies reveal the presence of enhanced conductivity at certain types of domain walls in BFO. We have completed detailed TEM studies of the physical structure at these domain walls as well as in-depth DFT calculations of the evolution of electronic structure at these domain walls. These studies reveal two major contributions to the observed conduction: the formation of an electrostatic potential at the domain walls as well as a structurally-driven change in the electronic structure (i.e., a lower band gap locally) at the domain walls. We will discuss the use of optical characterization techniques as a way of probing this change in electronic structure at domain walls as well as detailed IV characterization both in atmospheric and UHV environments. Finally, the evolution of magnetism at these domain walls has been studied through the use of photoemission measurements. Initial findings point to a significant change in the magnetic order at these domain walls in BFO.

IPUMS: Detailed global data on population characteristics

NASA Astrophysics Data System (ADS)

Kugler, T.

2017-12-01

Many new and exciting sources of data on human population distributions based on remote sensing, mobile technology, and other mechanisms are becoming available. These new data sources often provide fine scale spatial and/or temporal resolution. However, they typically focus on the location of population, with little or no information on population characteristics. The large and growing collection of data available through the IPUMS family of products complements datasets that provide spatial and temporal detail but little attribute detail by providing the full depth of characteristics covered by population censuses, including demographic, household structure, economic, employment, education, and housing characteristics. IPUMS International provides census microdata for 85 countries. Microdata provide the responses to every census question for each individual in a sample of households. Microdata identify the sub-national geographic unit in which a household is located, but for confidentiality reasons, identified units must include a minimum population, typically 20,000 people. Small-area aggregate data often describe much smaller geographic units, enabling study of detailed spatial patterns of population characteristics. However the structure of aggregate data tables is highly heterogeneous across countries, census years, and even topics within a given census, making these data difficult to work with in any systematic way. A recently funded project will assemble small-area aggregate population and agricultural census data published by national statistical offices. Through preliminary work collecting and cataloging over 10,000 tables, we have identified a small number of structural families that can be used to organize the many different structures. These structural families will form the basis for software tools to document and standardize the tables for ingest into a common database. Both the microdata and aggregate data are made available through IPUMS Terra

Potential and Limitations of the Modal Characterization of a Spacecraft Bus Structure by Means of Active Structure Elements

NASA Technical Reports Server (NTRS)

Grillenbeck, Anton M.; Dillinger, Stephan A.; Elliott, Kenny B.

1998-01-01

Theoretical and experimental studies have been performed to investigate the potential and limitations of the modal characterization of a typical spacecraft bus structure by means of active structure elements. The aim of these studies has been test and advance tools for performing an accurate on-orbit modal identification which may be characterized by the availability of a generally very limited test instrumentation, autonomous excitation capabilities by active structure elements and a zero-g environment. The NASA LARC CSI Evolutionary Testbed provided an excellent object for the experimental part of this study program. The main subjects of investigation were: (1) the selection of optimum excitation and measurement to unambiguously identify modes of interest; (2) the applicability of different types of excitation means with focus on active structure elements; and (3) the assessment of the modal identification potential of different types of excitation functions and modal analysis tools. Conventional as well as dedicated modal analysis tools were applied to determine modal parameters and mode shapes. The results will be presented and discussed based on orthogonality checks as well as on suitable indicators for the quality of the acquired modes with respect to modal purity. In particular, the suitability for modal analysis of the acquired frequency response functions as obtained by excitation with active structure elements will be demonstrated with the help of reciprocity checks. Finally, the results will be summarized in a procedure to perform an on-orbit modal identification, including an indication of limitation to be observed.

Structural characterization and aging of glassy pharmaceuticals made using acoustic levitation.

PubMed

Benmore, Chris J; Weber, J K R; Tailor, Amit N; Cherry, Brian R; Yarger, Jeffery L; Mou, Qiushi; Weber, Warner; Neuefeind, Joerg; Byrn, Stephen R

2013-04-01

Here, we report the structural characterization of several amorphous drugs made using the method of quenching molten droplets suspended in an acoustic levitator. (13) C NMR, X-ray, and neutron diffraction results are discussed for glassy cinnarizine, carbamazepine, miconazole nitrate, probucol, and clotrimazole. The (13) C NMR results did not find any change in chemical bonding induced by the amorphization process. High-energy X-ray diffraction results were used to characterize the ratio of crystalline to amorphous material present in the glasses over a period of 8 months. All the glasses were stable for at least 6 months except carbamazepine, which has a strong tendency to crystallize within a few months. Neutron and X-ray pair distribution function analyses were applied to the glassy materials, and the results were compared with their crystalline counterparts. The two diffraction techniques yielded similar results in most cases and identified distinct intramolecular and intermolecular correlations. The intramolecular scattering was calculated based on the crystal structure and fit to the measured X-ray structure factor. The resulting intermolecular pair distribution functions revealed broad-nearest and next-nearest neighbor molecule-molecule correlations. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:1290-1300, 2013. Copyright © 2013 Wiley Periodicals, Inc.

Characterizing the graded structure of false killer whale (Pseudorca crassidens) vocalizations.

PubMed

Murray, S O; Mercado, E; Roitblat, H L

1998-09-01

The vocalizations from two, captive false killer whales (Pseudorca crassidens) were analyzed. The structure of the vocalizations was best modeled as lying along a continuum with trains of discrete, exponentially damped sinusoidal pulses at one end and continuous sinusoidal signals at the other end. Pulse trains were graded as a function of the interval between pulses where the minimum interval between pulses could be zero milliseconds. The transition from a pulse train with no inter-pulse interval to a whistle could be modeled by gradations in the degree of damping. There were many examples of vocalizations that were gradually modulated from pulse trains to whistles. There were also vocalizations that showed rapid shifts in signal type--for example, switching immediately from a whistle to a pulse train. These data have implications when considering both the possible function(s) of the vocalizations and the potential sound production mechanism(s). A short-time duty cycle measure was developed to characterize the graded structure of the vocalizations. A random sample of 500 vocalizations was characterized by combining the duty cycle measure with peak frequency measurements. The analysis method proved to be an effective metric for describing the graded structure of false killer whale vocalizations.

Characterization of iron-phosphate-silicate chemical garden structures.

PubMed

Barge, Laura M; Doloboff, Ivria J; White, Lauren M; Stucky, Galen D; Russell, Michael J; Kanik, Isik

2012-02-28

Chemical gardens form when ferrous chloride hydrate seed crystals are added or concentrated solutions are injected into solutions of sodium silicate and potassium phosphate. Various precipitation morphologies are observed depending on silicate and phosphate concentrations, including hollow plumes, bulbs, and tubes. The growth of precipitates is controlled by the internal osmotic pressure, fluid buoyancy, and membrane strength. Additionally, rapid bubble-led growth is observed when silicate concentrations are high. ESEM/EDX analysis confirms compositional gradients within the membranes, and voltage measurements across the membranes during growth show a final potential of around 150-200 mV, indicating that electrochemical gradients are maintained across the membranes as growth proceeds. The characterization of chemical gardens formed with iron, silicate, and phosphate, three important components of an early earth prebiotic hydrothermal system, can help us understand the properties of analogous structures that likely formed at submarine alkaline hydrothermal vents in the Hadean-structures offering themselves as the hatchery of life. © 2011 American Chemical Society

Peering into the heart of galactic star formation: A detailed characterization of infrared-dark clouds

NASA Astrophysics Data System (ADS)

Ragan, Sarah E.

2009-09-01

study of sub- structure in particular shows that IRDCs are undergoing fragmentation and are the precursors to star clusters, and thus we have placed IRDCs in context with Galactic star formation. The characterization presented here offers new constraints on theories of molecular cloud fragmentation and clustered star formation.

Amyloid oligomer structure characterization from simulations: A general method

NASA Astrophysics Data System (ADS)

Nguyen, Phuong H.; Li, Mai Suan; Derreumaux, Philippe

2014-03-01

Amyloid oligomers and plaques are composed of multiple chemically identical proteins. Therefore, one of the first fundamental problems in the characterization of structures from simulations is the treatment of the degeneracy, i.e., the permutation of the molecules. Second, the intramolecular and intermolecular degrees of freedom of the various molecules must be taken into account. Currently, the well-known dihedral principal component analysis method only considers the intramolecular degrees of freedom, and other methods employing collective variables can only describe intermolecular degrees of freedom at the global level. With this in mind, we propose a general method that identifies all the structures accurately. The basis idea is that the intramolecular and intermolecular states are described in terms of combinations of single-molecule and double-molecule states, respectively, and the overall structures of oligomers are the product basis of the intramolecular and intermolecular states. This way, the degeneracy is automatically avoided. The method is illustrated on the conformational ensemble of the tetramer of the Alzheimer's peptide Aβ9-40, resulting from two atomistic molecular dynamics simulations in explicit solvent, each of 200 ns, starting from two distinct structures.

Structural and functional characterization of two alpha-synuclein strains

NASA Astrophysics Data System (ADS)

Bousset, Luc; Pieri, Laura; Ruiz-Arlandis, Gemma; Gath, Julia; Jensen, Poul Henning; Habenstein, Birgit; Madiona, Karine; Olieric, Vincent; Böckmann, Anja; Meier, Beat H.; Melki, Ronald

2013-10-01

α-synuclein aggregation is implicated in a variety of diseases including Parkinson’s disease, dementia with Lewy bodies, pure autonomic failure and multiple system atrophy. The association of protein aggregates made of a single protein with a variety of clinical phenotypes has been explained for prion diseases by the existence of different strains that propagate through the infection pathway. Here we structurally and functionally characterize two polymorphs of α-synuclein. We present evidence that the two forms indeed fulfil the molecular criteria to be identified as two strains of α-synuclein. Specifically, we show that the two strains have different structures, levels of toxicity, and in vitro and in vivo seeding and propagation properties. Such strain differences may account for differences in disease progression in different individuals/cell types and/or types of synucleinopathies.

Test method development for structural characterization of fiber composites at high temperatures

NASA Technical Reports Server (NTRS)

Mandell, J. F.; Grande, D. H.; Edwards, B.

1985-01-01

Test methods used for structural characterization of polymer matrix composites can be applied to glass and ceramic matrix composites only at low temperatures. New test methods are required for tensile, compressive, and shear properties of fiber composites at high temperatures. A tensile test which should be useful to at least 1000 C has been developed and used to characterize the properties of a Nicalon/glass composite up to the matrix limiting temperature of 600 C. Longitudinal and transverse unidirectional composite data are presented and discussed.

3D soil structure characterization of Biological Soil Crusts from Alpine Tarfala Valley

NASA Astrophysics Data System (ADS)

Mele, Giacomo; Gargiulo, Laura; Zucconi, Laura; D'Acqui, Luigi; Ventura, Stefano

2017-04-01

Cyanobacteria filaments, microfungal hyphae, lichen rhizinae and anchoring rhizoids of bryophytes all together contribute to induce formation of structure in the thin soil layer beneath the Biological Soil Crusts (BSCs). Quantitative assessment of the soil structure beneath the BSCs is primarily hindered by the fragile nature of the crusts. Therefore, the role of BSCs in affecting such soil physical property has been rarely addressed using direct measurements. In this work we applied non-destructive X-ray microtomography imaging on five different samples of BSCs collected in the Alpine Tarfala Valley (northern Sweden), which have already been characterized in terms of fungal biodiversity in a previous work. We obtained images of the 3D spatial organization of the soil underneath the BSCs and characterized its structure by applying procedures of image analysis allowing to determine pore size distribution, pore connectivity and aggregate size distribution. Results has then been correlated with the different fungal assemblages of the samples.

Analysis and characterization of structurally embedded vascular antennas using liquid metals

NASA Astrophysics Data System (ADS)

Hartl, Darren J.; Huff, Gregory H.; Pan, Hong; Smith, Lisa; Bradford, Robyn L.; Frank, Geoffrey J.; Baur, Jeffrey W.

2016-04-01

Over the past decade, a large body of research associated with the addition of microvascular networks to structural composites has been generated. The engineering goal is most often the extension of structural utility to include extended functionalities such as self-healing or improved thermal management and resilience. More recently, efforts to design reconfigurable embedded electronics via the incorporation of non-toxic liquid metals have been initiated. A wide range of planar antenna configurations are possible, and the trade-offs between structural effects, other system costs, and increased flexibility in transmitting and receiving frequencies are being explored via the structurally embedded vascular antenna (SEVA) concept. This work describes for the first time the design of a bowtie-like tunable liquid metal-based antenna for integration into a structural composite for electromagnetic use. The design of both the solid/fluid feed structure and fluid transmission lines are described and analysis results regarding the RF performance of the antenna are provided. Fabrication methods for the SEVA are explained in detail and as-fabricated components are described. Challenges associated with both fabrication and system implementation and testing are elucidated. Results from preliminary RF testing indicate that in situ response tuning is feasible in these novel multifunctional composites.

Tools for Designing and Analyzing Structures

NASA Technical Reports Server (NTRS)

Luz, Paul L.

2005-01-01

Structural Design and Analysis Toolset is a collection of approximately 26 Microsoft Excel spreadsheet programs, each of which performs calculations within a different subdiscipline of structural design and analysis. These programs present input and output data in user-friendly, menu-driven formats. Although these programs cannot solve complex cases like those treated by larger finite element codes, these programs do yield quick solutions to numerous common problems more rapidly than the finite element codes, thereby making it possible to quickly perform multiple preliminary analyses - e.g., to establish approximate limits prior to detailed analyses by the larger finite element codes. These programs perform different types of calculations, as follows: 1. determination of geometric properties for a variety of standard structural components; 2. analysis of static, vibrational, and thermal- gradient loads and deflections in certain structures (mostly beams and, in the case of thermal-gradients, mirrors); 3. kinetic energies of fans; 4. detailed analysis of stress and buckling in beams, plates, columns, and a variety of shell structures; and 5. temperature dependent properties of materials, including figures of merit that characterize strength, stiffness, and deformation response to thermal gradients

Multiscale tomography of buried magnetic structures: its use in the localization and characterization of archaeological structures

NASA Astrophysics Data System (ADS)

Saracco, Ginette; Moreau, Frédérique; Mathé, Pierre-Etienne; Hermitte, Daniel; Michel, Jean-Marie

2007-10-01

We have previously developed a method for characterizing and localizing `homogeneous' buried sources, from the measure of potential anomalies at a fixed height above ground (magnetic, electric and gravity). This method is based on potential theory and uses the properties of the Poisson kernel (real by definition) and the continuous wavelet theory. Here, we relax the assumption on sources and introduce a method that we call the `multiscale tomography'. Our approach is based on the harmonic extension of the observed magnetic field to produce a complex source by use of a complex Poisson kernel solution of the Laplace equation for complex potential field. A phase and modulus are defined. We show that the phase provides additional information on the total magnetic inclination and the structure of sources, while the modulus allows us to characterize its spatial location, depth and `effective degree'. This method is compared to the `complex dipolar tomography', extension of the Patella method that we previously developed. We applied both methods and a classical electrical resistivity tomography to detect and localize buried archaeological structures like antique ovens from magnetic measurements on the Fox-Amphoux site (France). The estimates are then compared with the results of excavations.

Pore- and micro-structural characterization of a novel structural binder based on iron carbonation

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

Das, Sumanta, E-mail: Sumanta.Das@asu.edu; Stone, David, E-mail: dajstone@gmail.com; Convey, Diana, E-mail: Diana.Convey@asu.edu

2014-12-15

The pore- and micro-structural features of a novel binding material based on the carbonation of waste metallic iron powder are reported in this paper. The binder contains metallic iron powder as the major ingredient, followed by additives containing silica and alumina to facilitate favorable reaction product formation. Compressive strengths sufficient for a majority of concrete applications are attained. The material pore structure is investigated primarily through mercury intrusion porosimetry whereas electron microscopy is used for microstructural characterization. Reduction in the overall porosity and the average pore size with an increase in carbonation duration from 1 day to 4 days ismore » noticed. The pore structure features are used in predictive models for gas and moisture transport (water vapor diffusivity and moisture permeability) through the porous medium which dictates its long-term durability when used in structural applications. Comparisons of the pore structure with those of a Portland cement paste are also provided. The morphology of the reaction products in the iron-based binder, and the distribution of constituent elements in the microstructure are also reported. - Highlights: • Carbonation of iron produces a dense microstructure. • Pore volume in iron carbonate lower, critical size higher than those in OPC pastes • Reaction product contains iron, carbon, silicon, aluminum and calcium. • Power-law for porosity-moisture permeability relationship was established.« less

Genome-wide characterization of genetic diversity and population structure in Secale

PubMed Central

2014-01-01

Background Numerous rye accessions are stored in ex situ genebanks worldwide. Little is known about the extent of genetic diversity contained in any of them and its relation to contemporary varieties, since to date rye genetic diversity studies had a very limited scope, analyzing few loci and/ or few accessions. Development of high throughput genotyping methods for rye opened the possibility for genome wide characterizations of large accessions sets. In this study we used 1054 Diversity Array Technology (DArT) markers with defined chromosomal location to characterize genetic diversity and population structure in a collection of 379 rye accessions including wild species, landraces, cultivated materials, historical and contemporary rye varieties. Results Average genetic similarity (GS) coefficients and average polymorphic information content (PIC) values varied among chromosomes. Comparison of chromosome specific average GS within and between germplasm sub-groups indicated regions of chromosomes 1R and 4R as being targeted by selection in current breeding programs. Bayesian clustering, principal coordinate analysis and Neighbor Joining clustering demonstrated that source and improvement status contributed significantly to the structure observed in the analyzed set of Secale germplasm. We revealed a relatively limited diversity in improved rye accessions, both historical and contemporary, as well as lack of correlation between clustering of improved accessions and geographic origin, suggesting common genetic background of rye accessions from diverse geographic regions and extensive germplasm exchange. Moreover, contemporary varieties were distinct from the remaining accessions. Conclusions Our results point to an influence of reproduction methods on the observed diversity patterns and indicate potential of ex situ collections for broadening the genetic diversity in rye breeding programs. Obtained data show that DArT markers provide a realistic picture of the genetic

Resolving the detailed structure of cortical and thalamic neurons in the adult rat brain with refined biotinylated dextran amine labeling.

PubMed

Ling, Changying; Hendrickson, Michael L; Kalil, Ronald E

2012-01-01

Biotinylated dextran amine (BDA) has been used frequently for both anterograde and retrograde pathway tracing in the central nervous system. Typically, BDA labels axons and cell somas in sufficient detail to identify their topographical location accurately. However, BDA labeling often has proved to be inadequate to resolve the fine structural details of axon arbors or the dendrites of neurons at a distance from the site of BDA injection. To overcome this limitation, we varied several experimental parameters associated with the BDA labeling of neurons in the adult rat brain in order to improve the sensitivity of the method. Specifically, we compared the effect on labeling sensitivity of: (a) using 3,000 or 10,000 MW BDA; (b) injecting different volumes of BDA; (c) co-injecting BDA with NMDA; and (d) employing various post-injection survival times. Following the extracellular injection of BDA into the visual cortex, labeled cells and axons were observed in both cortical and thalamic areas of all animals studied. However, the detailed morphology of axon arbors and distal dendrites was evident only under optimal conditions for BDA labeling that take into account the: molecular weight of the BDA used, concentration and volume of BDA injected, post-injection survival time, and toning of the resolved BDA with gold and silver. In these instances, anterogradely labeled axons and retrogradely labeled dendrites were resolved in fine detail, approximating that which can be achieved with intracellularly injected compounds such as biocytin or fluorescent dyes.

Resolving the Detailed Structure of Cortical and Thalamic Neurons in the Adult Rat Brain with Refined Biotinylated Dextran Amine Labeling

PubMed Central

Ling, Changying; Hendrickson, Michael L.; Kalil, Ronald E.

2012-01-01

Biotinylated dextran amine (BDA) has been used frequently for both anterograde and retrograde pathway tracing in the central nervous system. Typically, BDA labels axons and cell somas in sufficient detail to identify their topographical location accurately. However, BDA labeling often has proved to be inadequate to resolve the fine structural details of axon arbors or the dendrites of neurons at a distance from the site of BDA injection. To overcome this limitation, we varied several experimental parameters associated with the BDA labeling of neurons in the adult rat brain in order to improve the sensitivity of the method. Specifically, we compared the effect on labeling sensitivity of: (a) using 3,000 or 10,000 MW BDA; (b) injecting different volumes of BDA; (c) co-injecting BDA with NMDA; and (d) employing various post-injection survival times. Following the extracellular injection of BDA into the visual cortex, labeled cells and axons were observed in both cortical and thalamic areas of all animals studied. However, the detailed morphology of axon arbors and distal dendrites was evident only under optimal conditions for BDA labeling that take into account the: molecular weight of the BDA used, concentration and volume of BDA injected, post-injection survival time, and toning of the resolved BDA with gold and silver. In these instances, anterogradely labeled axons and retrogradely labeled dendrites were resolved in fine detail, approximating that which can be achieved with intracellularly injected compounds such as biocytin or fluorescent dyes. PMID:23144777

Biophysical characterization and structure of the Fab fragment from the NIST reference antibody, RM 8671.

PubMed

Karageorgos, Ioannis; Gallagher, Elyssia S; Galvin, Connor; Gallagher, D Travis; Hudgens, Jeffrey W

2017-11-01

Monoclonal antibody pharmaceuticals are the fastest-growing class of therapeutics, with a wide range of clinical applications. To assure their safety, these protein drugs must demonstrate highly consistent purity and stability. Key to these objectives is higher order structure measurements validated by calibration to reference materials. We describe preparation, characterization, and crystal structure of the Fab fragment prepared from the NIST Reference Antibody RM 8671 (NISTmAb). NISTmAb is a humanized IgG1κ antibody, produced in murine cell culture and purified by standard biopharmaceutical production methods, developed at the National Institute of Standards and Technology (NIST) to serve as a reference material. The Fab fragment was derived from NISTmAb through papain cleavage followed by protein A based purification. The purified Fab fragment was characterized by SDS-PAGE, capillary gel electrophoresis, multi-angle light scattering, size exclusion chromatography, mass spectrometry, and x-ray crystallography. The crystal structure at 0.2 nm resolution includes four independent Fab molecules with complete light chains and heavy chains through Cys 223, enabling assessment of conformational variability and providing a well-characterized reference structure for research and engineering applications. This nonproprietary, publically available reference material of known higher-order structure can support metrology in biopharmaceutical applications, and it is a suitable platform for validation of molecular modeling studies. Published by Elsevier Ltd.

Molecular details of secretory phospholipase A2 from flax (Linum usitatissimum L.) provide insight into its structure and function.

PubMed

Gupta, Payal; Dash, Prasanta K

2017-09-11

Secretory phospholipase A 2 (sPLA 2 ) are low molecular weight proteins (12-18 kDa) involved in a suite of plant cellular processes imparting growth and development. With myriad roles in physiological and biochemical processes in plants, detailed analysis of sPLA 2 in flax/linseed is meagre. The present work, first in flax, embodies cloning, expression, purification and molecular characterisation of two distinct sPLA 2 s (I and II) from flax. PLA 2 activity of the cloned sPLA 2 s were biochemically assayed authenticating them as bona fide phospholipase A 2 . Physiochemical properties of both the sPLA 2 s revealed they are thermostable proteins requiring di-valent cations for optimum activity.While, structural analysis of both the proteins revealed deviations in the amino acid sequence at C- & N-terminal regions; hydropathic study revealed LusPLA 2 I as a hydrophobic protein and LusPLA 2 II as a hydrophilic protein. Structural analysis of flax sPLA 2 s revealed that secondary structure of both the proteins are dominated by α-helix followed by random coils. Modular superimposition of LusPLA 2 isoforms with rice sPLA 2 confirmed monomeric structural preservation among plant phospholipase A 2 and provided insight into structure of folded flax sPLA 2 s.

Structural characterization of hydrothermally synthesized MnO2 nanorods

NASA Astrophysics Data System (ADS)

A'yuni, D. Q.; Alkian, I.; Sya'diyah, F. K.; Kadarisman; Darari, A.; Gunawan, V.; Subagio, A.

2017-11-01

We prepared the hydrothermal method to synthesize MnO2 nanorods with controlled structure. KMnO4 and HCl with the various molar ratio (1:2,1:6,1:8) reacted at 160°C for three hours to form MnO2 nanorods. The study found that changing the molar ratio can control the structure and morphology of MnO2. The result revealed that MnO2 formed in nanorod microstructures with different crystallographic structure and phase composition of each molar ratio. The diffraction peaks observed at 2θ values of 28.9°, 37.8°, 40.9°, 49.7° and 60.5° respectively indexed to (110), (101), (200), (411) and (521) plane reflections of a tetragonal phase of β-MnO2 and α-MnO2. The characterization of the morphology showed that the diameters of nanorod microstructures of MnO2 ranging from 30 to 145 nm with length ranging from 0.5 to 3 μm. These MnO2 nanorods product would be potentially used in energy storage devices.

Biochemical and Structural Characterization of the Human TL1A Ectodomain†¶

PubMed Central

Zhan, Chenyang; Yan, Qingrong; Patskovsky, Yury; Li, Zhenhong; Toro, Rafael; Meyer, Amanda; Cheng, Huiyong; Brenowitz, Michael; Nathenson, Stanley G; Almo, Steven C

2009-01-01

TNF-like 1A (TL1A) is a newly described member of the TNF superfamily that is directly implicated in the pathogenesis of autoimmune diseases, including inflammatory bowel disease, atherosclerosis and rheumatoid arthritis. We report the crystal structure of the human TL1A extracellular domain at a resolution of 2.5 Å, which reveals a jelly-roll fold typical of the TNF superfamily. This structural information, in combination with complementary mutagenesis and biochemical characterization, provides insights into the binding interface and the specificity of the interactions between TL1A and the DcR3 and DR3 receptors. These studies suggest that the mode of interaction between TL1A and DcR3 differs from other characterized TNF ligand/receptor complexes. In addition, we have generated functional TL1A mutants with altered disulfide bonding capability that exhibit enhanced solution properties, which will facilitate the production of materials for future cell-based and whole animal studies. In summary, these studies provide insights into the structure and function of TL1A and provide the basis for the rational manipulation of its interactions with cognate receptors. PMID:19522538

Ultrasonic characterization of damage in a simulated CF-18 composite structure

NASA Astrophysics Data System (ADS)

McRae, K. I.; Finlayson, R. D.; Sturrock, W. R.; Liesch, D. S.

1993-02-01

A simulated CF-18 aircraft door component was constructed and subjected to treatment during manufacturing with the object of inducing damage in the composite material in a known and well-defined manner. The simulated component was then sent to participants in a nondestructive evaluation study. Results are reported for tests conducted with a scanning apparatus and data acquisition system which consisted of three components: ultrasonic transducer and scanner comprising a two-axis scanning frame to which a modified commercial transducer was attached; an acquisition system for ultrasonic data known as Signal Processing Ultrasonic Device (SPUD); and a data analysis and display system (DETECT/NDE) specifically designed to manipulate large three dimensional ultrasonic data sets. A series of five large-area scans was performed, each scan about 52 cm square. A total of eight regions of interest were identified for a more detailed analysis of the delamination damage, seven detailed scans covering a 13-cm square and one covering a 20.8-cm square. It was often possible to identify the probable source of the damage as that resulting from impact or caused by overloading of fasteners. Flaws of all significant dimensions were located and fully characterized using the ultrasonic procedure.

In detail monazite characterization in a carbonatite weathering profile - a new tool for landscape geochronology

NASA Astrophysics Data System (ADS)

Renno, A. D.; Le Bras, L.; Ziegenrücker, R.; Couffignal, F.; Wiedenbeck, M.; Haser, S.; Hlawacek, G.

2016-12-01

The Post-Gondwana geology of South Africa is marked by two prominent planation surfaces, the result of two distinct phases of uplift and erosion. The first of these took place during the mid- to late Cretaceous (the so-called "African planation"), whilst the second is tentatively placed into the Miocene or Oligocene (the "Post-African I planation"). Humid and warm climatic conditions are recorded by deep lateritic weathering columns of suitable lithologies. The present study tests the suitability of U-Th-Pb dating on supergene monazite as a geochronometer for landscape formation and the downward progression of the chemical weathering process. We investigated material from the Zandkopsdrift carbonatite, Namaqualand, South Africa, a pipe-shaped intrusion located in the Northern Cape Province of South Africa. The age of carbonatite intrusion has been determined to be Eocene (54-56 Ma). This carbonatite has a well-developed lateritic cap that is more than 80 m thick in places and that is highly enriched in REE's hosted mostly by very fine crystalline monazite of presumably supergene origin. Due to the fact that the age of intrusion postdates the African planation surface, the lateritic cap almost certainly marks the Post-African I erosion surface. Both the onset and duration of the Post-African I cycle of erosion remain uncertain. This study addresses the duration of the Post-African I event through the dating of supergene monazite from the Zandkopsdrift laterite cap. A detailed description of the petrographic and mineralogical properties has identified the most promising samples for dating using secondary ion mass spectrometry (SIMS). A detailed description of the internal structure, microporosity and inclusions as well as intergrowths and pseudomorphic mineral formations has helped greatly toward understand the origins of the Zandkopsdrift sequence and the genesis of the REE within this profile. These data establish important anchor points for the reconstruction of

Advanced analysis of complex seismic waveforms to characterize the subsurface Earth structure

NASA Astrophysics Data System (ADS)

Jia, Tianxia

2011-12-01

This thesis includes three major parts, (1) Body wave analysis of mantle structure under the Calabria slab, (2) Spatial Average Coherency (SPAC) analysis of microtremor to characterize the subsurface structure in urban areas, and (3) Surface wave dispersion inversion for shear wave velocity structure. Although these three projects apply different techniques and investigate different parts of the Earth, their aims are the same, which is to better understand and characterize the subsurface Earth structure by analyzing complex seismic waveforms that are recorded on the Earth surface. My first project is body wave analysis of mantle structure under the Calabria slab. Its aim is to better understand the subduction structure of the Calabria slab by analyzing seismograms generated by natural earthquakes. The rollback and subduction of the Calabrian Arc beneath the southern Tyrrhenian Sea is a case study of slab morphology and slab-mantle interactions at short spatial scale. I analyzed the seismograms traversing the Calabrian slab and upper mantle wedge under the southern Tyrrhenian Sea through body wave dispersion, scattering and attenuation, which are recorded during the PASSCAL CAT/SCAN experiment. Compressional body waves exhibit dispersion correlating with slab paths, which is high-frequency components arrivals being delayed relative to low-frequency components. Body wave scattering and attenuation are also spatially correlated with slab paths. I used this correlation to estimate the positions of slab boundaries, and further suggested that the observed spatial variation in near-slab attenuation could be ascribed to mantle flow patterns around the slab. My second project is Spatial Average Coherency (SPAC) analysis of microtremors for subsurface structure characterization. Shear-wave velocity (Vs) information in soil and rock has been recognized as a critical parameter for site-specific ground motion prediction study, which is highly necessary for urban areas located

Structural characterization/correlation of calorimetric properties of coal fluids: Second annual report, September 1, 1986-August 31, 1987

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

Starling, K.E.; Mallinson, R.G.; Li, M.H.

The objective of this research is to examine the relationship between the calorimetric properties of coal fluids and their molecular functional group composition. Coal fluid samples which have had their calorimetric properties measured are characterized using proton NMR, ir, and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal fluid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for ideal gas heat capacities are then examined withinmore » an existing equation of state methodology to determine an optimal correlation. The optimal correlation for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model is examined.« less

Structural and functional characterization of two alpha-synuclein strains

PubMed Central

Bousset, Luc; Pieri, Laura; Ruiz-Arlandis, Gemma; Gath, Julia; Jensen, Poul Henning; Habenstein, Birgit; Madiona, Karine; Olieric, Vincent; Böckmann, Anja; Meier, Beat H.; Melki, Ronald

2013-01-01

α-synuclein aggregation is implicated in a variety of diseases including Parkinson’s disease, dementia with Lewy bodies, pure autonomic failure and multiple system atrophy. The association of protein aggregates made of a single protein with a variety of clinical phenotypes has been explained for prion diseases by the existence of different strains that propagate through the infection pathway. Here we structurally and functionally characterize two polymorphs of α-synuclein. We present evidence that the two forms indeed fulfil the molecular criteria to be identified as two strains of α-synuclein. Specifically, we show that the two strains have different structures, levels of toxicity, and in vitro and in vivo seeding and propagation properties. Such strain differences may account for differences in disease progression in different individuals/cell types and/or types of synucleinopathies. PMID:24108358

Structural characterization of arginine-vasopressin and lysine-vasopressin by Fourier- transform ion cyclotron resonance mass spectrometry and infrared multiphoton dissociation.

PubMed

Bianco, Giuliana; Battista, Fabio; Buchicchio, Alessandro; Amarena, Concetta G; Schmitt-Kopplin, Philippe; Guerrieri, Antonio

2015-01-01

Arginine-vasopressin (AVP) and lysine-vasopressin (LVP) were analyzed by reversed-phase liquid chromatography/mass spectrometry (LC-MS) using Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) electrospray ionization (ESI) in the positive ion mode. LVP and AVP exhibited the protonated adduct [M+H](+) as the predominant ion at m/z 1056.43965 and at m/z 1084.44561, respectively. Infrared multiphoton dissociation (IRMPD), using a CO(2) laser source at a wavelength of 10.6 μm, was applied to protonated vasopressin molecules. The IRMPD mass spectra presented abundant mass fragments essential for a complete structural information. Several fragment ions, shared between two target molecules, are discussed in detail. Some previously unpublished fragments were identified unambiguously utilizing the high resolution and accurate mass information provided by the FT-ICR mass spectrometer. The opening of the disulfide loop and the cleavage of the peptide bonds within the ring were observed even under low-energy fragmentation conditions. Coupling the high-performance FT-ICR mass spectrometer with IRMPD as a contemporary fragmentation technique proved to be very promising for the structural characterization of vasopressin.

Detailed characterization of bio-oil from pyrolysis of non-edible seed-cakes by Fourier Transform Infrared Spectroscopy (FTIR) and gas chromatography mass spectrometry (GC-MS) techniques.

PubMed

Sugumaran, Vatsala; Prakash, Shanti; Ramu, Emmandi; Arora, Ajay Kumar; Bansal, Veena; Kagdiyal, Vivekanand; Saxena, Deepak

2017-07-15

Bio-oil obtained from pyrolysis is highly complicated mixture with valued chemicals. In order to reduce the complexity for unambiguous characterization of components present in bio-oil, solvent extractions using different solvents with increasing polarity have been adopted. The fractions have been analyzed by Fourier transform infrared (FTIR) spectroscopy for identifying the functional groups and Gas chromatography-mass spectrometry (GC-MS), for detailed characterization of components present in various fractions, thereby providing in-depth information at molecular level of various components in bio-oil. This paper reveals the potential of the analytical techniques in identification and brings out the similarities as well as differences in the components present in the bio-oil obtained from two non-edible oil seed-cakes, viz., Jatropha and Karanjia. Copyright © 2017 Elsevier B.V. All rights reserved.

Molecular characterization of HIV-1 Nef and ACOT8 interaction: insights from in silico structural predictions and in vitro functional assays

NASA Astrophysics Data System (ADS)

Serena, Michela; Giorgetti, Alejandro; Busato, Mirko; Gasparini, Francesca; Diani, Erica; Romanelli, Maria Grazia; Zipeto, Donato

2016-03-01

HIV-1 Nef interacts with several cellular proteins, among which the human peroxisomal thioesterase 8 (ACOT8). This interaction may be involved in the endocytosis regulation of membrane proteins and might modulate lipid composition in membrane rafts. Nef regions involved in the interaction have been experimentally characterized, whereas structural details of the ACOT8 protein are unknown. The lack of structural information hampers the comprehension of the functional consequences of the complex formation during HIV-1 infection. We modelled, through in silico predictions, the ACOT8 structure and we observed a high charge complementarity between Nef and ACOT8 surfaces, which allowed the identification of the ACOT8 putative contact points involved in the interaction. The predictions were validated by in vitro assays through the development of ACOT8 deletion mutants. Coimmunoprecipitation and immunofluorescence analyses showed that ACOT8 Arg45-Phe55 and Arg86-Pro93 regions are involved in Nef association. In addition, K91S mutation abrogated the interaction with Nef, indicating that Lys91 plays a key role in the interaction. Finally, when associated with ACOT8, Nef may be preserved from degradation. These findings improve the comprehension of the association between HIV-1 Nef and ACOT8, helping elucidating the biological effect of their interaction.

Integrating prior information into microwave tomography Part 1: Impact of detail on image quality.

PubMed

Kurrant, Douglas; Baran, Anastasia; LoVetri, Joe; Fear, Elise

2017-12-01

The authors investigate the impact that incremental increases in the level of detail of patient-specific prior information have on image quality and the convergence behavior of an inversion algorithm in the context of near-field microwave breast imaging. A methodology is presented that uses image quality measures to characterize the ability of the algorithm to reconstruct both internal structures and lesions embedded in fibroglandular tissue. The approach permits key aspects that impact the quality of reconstruction of these structures to be identified and quantified. This provides insight into opportunities to improve image reconstruction performance. Patient-specific information is acquired using radar-based methods that form a regional map of the breast. This map is then incorporated into a microwave tomography algorithm. Previous investigations have demonstrated the effectiveness of this approach to improve image quality when applied to data generated with two-dimensional (2D) numerical models. The present study extends this work by generating prior information that is customized to vary the degree of structural detail to facilitate the investigation of the role of prior information in image formation. Numerical 2D breast models constructed from magnetic resonance (MR) scans, and reconstructions formed with a three-dimensional (3D) numerical breast model are used to assess if trends observed for the 2D results can be extended to 3D scenarios. For the blind reconstruction scenario (i.e., no prior information), the breast surface is not accurately identified and internal structures are not clearly resolved. A substantial improvement in image quality is achieved by incorporating the skin surface map and constraining the imaging domain to the breast. Internal features within the breast appear in the reconstructed image. However, it is challenging to discriminate between adipose and glandular regions and there are inaccuracies in both the structural properties of

Cornice Detail of Rake, Cornice Detail of Eave, Wood DoubleHung ...

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

Cornice Detail of Rake, Cornice Detail of Eave, Wood Double-Hung Window Details, Wood Door Details - Boxley Grist Mill, Boxley vicinity on State Route 43, Buffalo National River, Ponca, Newton County, AR

Design, Fabrication and Characterization of Thin Film Structures through Oxidation Kinetics

NASA Astrophysics Data System (ADS)

Diaz Leon, Juan Jose

Materials science and engineering is devoted to the understanding of the physics and chemistry of materials at the mesoscale and to applying that knowledge into real-life applications. In this work, different oxide materials and different oxidation methods are studied from a materials science point of view and for specific applications. First, the deposition of complex metal oxides is explored for solar energy concentration. This requires a number of multi-cation oxide structures such as thin-film dielectric barriers, low loss waveguides or the use of continuously graded composition oxides for antireflection coatings and light concentration. Then, oxidation via Joule heating is used for the self-alignment of a selector on top of a memristor structure on a nanovia. Simulations are used to explore the necessary voltage for the insulator-to-metal transition temperature of NbO2 using finite element analysis, followed by the fabrication and the characterization of such a device. Finally, long-term copper oxidation at room temperature and pressure is studied using optical techniques. Alternative characterization techniques are used to confirm the growth rate and phase change, and an application of copper oxide as a volatile conductive bridge is shown. All these examples show how the combination of novel simulation, fabrication and characterization techniques can be used to understand physical mechanisms and enable disruptive technologies in fields such as solar cells, light emitting diodes, photodetectors or memory devices.

Detailed Quantitative Classifications of Galaxy Morphology

NASA Astrophysics Data System (ADS)

Nair, Preethi

2018-01-01

Understanding the physical processes responsible for the growth of galaxies is one of the key challenges in extragalactic astronomy. The assembly history of a galaxy is imprinted in a galaxy’s detailed morphology. The bulge-to-total ratio of galaxies, the presence or absence of bars, rings, spiral arms, tidal tails etc, all have implications for the past merger, star formation, and feedback history of a galaxy. However, current quantitative galaxy classification schemes are only useful for broad binning. They cannot classify or exploit the wide variety of galaxy structures seen in nature. Therefore, comparisons of observations with theoretical predictions of secular structure formation have only been conducted on small samples of visually classified galaxies. However large samples are needed to disentangle the complex physical processes of galaxy formation. With the advent of large surveys, like the Sloan Digital Sky Survey (SDSS) and the upcoming Large Synoptic Survey Telescope (LSST) and WFIRST, the problem of statistics will be resolved. However, the need for a robust quantitative classification scheme will still remain. Here I will present early results on promising machine learning algorithms that are providing detailed classifications, identifying bars, rings, multi-armed spiral galaxies, and Hubble type.

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross ...

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

Horizontal Cross Bracing Detail, Vertical Cross Bracing Detail, Horizontal Cross Bracing Joint, Vertical Cross Bracing End Detail - Ceylon Covered Bridge, Limberlost Park, spanning Wabash River at County Road 900 South, Geneva, Adams County, IN

Structural and Biochemical Characterization of AidC, a Quorum-Quenching Lactonase With Atypical Selectivity

PubMed Central

Mascarenhas, Romila; Thomas, Pei W.; Wu, Chun-Xiang; Nocek, Boguslaw P.; Hoang, Quyen Q.; Liu, Dali; Fast, Walter

2015-01-01

Quorum-quenching catalysts are of interest for potential application as biochemical tools to interrogate interbacterial communication pathways, as anti-biofouling agents, and as anti-infective agents in plants and animals. Herein, the structure and function of AidC, an N-acyl-L-homoserine (AHL) lactonase from Chryseobacterium, is characterized. Steady-state kinetics show that zinc-supplemented AidC is one of the most efficient wild-type quorum-quenching enzymes characterized to date, with a kcat/KM value of approximately 2 × 106 M−1s−1 for N-heptanoyl-L-homoserine lactone. The enzyme has stricter substrate selectivity and significantly lower KM values (ca. 50 μM for preferred substrates) than typical AHL lactonases (ca. > 1 mM). X-ray crystal structures of AidC alone, and with the product N-hexanoyl-L-homoserine were determined at resolutions of 1.09 and 1.67 Å, respectively. Each structure displays as a dimer, and dimeric oligiomerization was also observed in solution by size-exclusion chromatography coupled with multi-angle light scattering. The structures reveal two atypical features as compared to previously characterized AHL lactonases: a ‘kinked’ α-helix that forms part of a closed binding pocket which provides affinity and enforces selectivity for AHL substrates, and an active-site His substitution that is usually found in a homologous family of phosphodiesterases. Implications for the catalytic mechanism of AHL lactonases are discussed. PMID:26115006

Structural and biochemical characterization of AidC, a quorum-quenching lactonase with atypical selectivity

DOE PAGES

Mascarenhas, Romila; Thomas, Pei W.; Wu, Chun -Xiang; ...

2015-06-26

Quorum-quenching catalysts are of interest for potential application as biochemical tools for interrogating interbacterial communication pathways, as antibiofouling agents, and as anti-infective agents in plants and animals. Herein, the structure and function of AidC, an N-acyl-l-homoserine lactone (AHL) lactonase from Chryseobacterium, is characterized. Steady-state kinetics show that zinc-supplemented AidC is the most efficient wild-type quorum-quenching enzymes characterized to date, with a k cat/K M value of approximately 2 × 10 6 M -1 s -1 for N-heptanoyl-l-homoserine lactone. The enzyme has stricter substrate selectivity and significantly lower KM values (ca. 50 μM for preferred substrates) compared to those of typicalmore » AHL lactonases (ca. >1 mM). X-ray crystal structures of AidC alone and with the product N-hexanoyl-l-homoserine were determined at resolutions of 1.09 and 1.67 Å, respectively. Each structure displays as a dimer, and dimeric oligiomerization was also observed in solution by size-exclusion chromatography coupled with multiangle light scattering. Lastly, the structures reveal two atypical features as compared to previously characterized AHL lactonases: a "kinked" α-helix that forms part of a closed binding pocket that provides affinity and enforces selectivity for AHL substrates and an active-site His substitution that is usually found in a homologous family of phosphodiesterases. We discuss implications for the catalytic mechanism of AHL lactonases.« less

Structural and biochemical characterization of AidC, a quorum-quenching lactonase with atypical selectivity

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

Mascarenhas, Romila; Thomas, Pei W.; Wu, Chun -Xiang

Quorum-quenching catalysts are of interest for potential application as biochemical tools for interrogating interbacterial communication pathways, as antibiofouling agents, and as anti-infective agents in plants and animals. Herein, the structure and function of AidC, an N-acyl-l-homoserine lactone (AHL) lactonase from Chryseobacterium, is characterized. Steady-state kinetics show that zinc-supplemented AidC is the most efficient wild-type quorum-quenching enzymes characterized to date, with a k cat/K M value of approximately 2 × 10 6 M -1 s -1 for N-heptanoyl-l-homoserine lactone. The enzyme has stricter substrate selectivity and significantly lower KM values (ca. 50 μM for preferred substrates) compared to those of typicalmore » AHL lactonases (ca. >1 mM). X-ray crystal structures of AidC alone and with the product N-hexanoyl-l-homoserine were determined at resolutions of 1.09 and 1.67 Å, respectively. Each structure displays as a dimer, and dimeric oligiomerization was also observed in solution by size-exclusion chromatography coupled with multiangle light scattering. Lastly, the structures reveal two atypical features as compared to previously characterized AHL lactonases: a "kinked" α-helix that forms part of a closed binding pocket that provides affinity and enforces selectivity for AHL substrates and an active-site His substitution that is usually found in a homologous family of phosphodiesterases. We discuss implications for the catalytic mechanism of AHL lactonases.« less

Synthesis and structural characterization of CdS nanoparticles

NASA Astrophysics Data System (ADS)

Kotkata, M. F.; Masoud, A. E.; Mohamed, M. B.; Mahmoud, E. A.

2009-08-01

Amorphous CdS nanoparticles capped with cetyltrimethyl ammonium bromide (CTAB) were synthesised under various conditions using a coprecipitation method. A blue shift in the band gap was observed in the UV-visible absorption spectra indicating the formation of nanoparticles of an approximate size of 8 nm. The recorded transmission electron micrographs confirmed this result. The phase-nature, phase transformation as well as the structure of the synthesised CdS nanoparticles have been extensively characterized using X-ray diffraction (XRD), radial distribution function (RDF), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), Raman scattering (RS) and/or heat stage X-ray diffraction (HSXRD). Analysis of the obtained results revealed that the synthesised amorphous CdS nanoparticles could be transformed into CdS nanocrystals having a zinc blende or a wurtzite structure, relying on the applied heat treatment scheme. The rate of nanocrystal growth depends on the aging period, prior filtering the reacted materials, and its relation to the quality of the capping process. Five days aging period tends to enhance the stability of the grown phase with a remarkable surface stability.

Cryo-Electron Tomography for Structural Characterization of Macromolecular Complexes

PubMed Central

Cope, Julia; Heumann, John; Hoenger, Andreas

2011-01-01

Cryo-electron tomography (cryo-ET) is an emerging 3-D reconstruction technology that combines the principles of tomographic 3-D reconstruction with the unmatched structural preservation of biological material embedded in vitreous ice. Cryo-ET is particularly suited to investigating cell-biological samples and large macromolecular structures that are too polymorphic to be reconstructed by classical averaging-based 3-D reconstruction procedures. This unit aims to make cryo-ET accessible to newcomers and discusses the specialized equipment required, as well as the relevant advantages and hurdles associated with sample preparation by vitrification and cryo-ET. Protocols describe specimen preparation, data recording and 3-D data reconstruction for cryo-ET, with a special focus on macromolecular complexes. A step-by-step procedure for specimen vitrification by plunge freezing is provided, followed by the general practicalities of tilt-series acquisition for cryo-ET, including advice on how to select an area appropriate for acquiring a tilt series. A brief introduction to the underlying computational reconstruction principles applied in tomography is described, along with instructions for reconstructing a tomogram from cryo-tilt series data. Finally, a method is detailed for extracting small subvolumes containing identical macromolecular structures from tomograms for alignment and averaging as a means to increase the signal-to-noise ratio and eliminate missing wedge effects inherent in tomographic reconstructions. PMID:21842467

Unraveling Structure-Property Relationships in Polymer Blends for Intelligent Materials Design

NASA Astrophysics Data System (ADS)

Irwin, Matthew Tyler

Block polymers provide an accessible route to structured, composite materials by combining two or more components with disparate mechanical, chemical, and electrical properties into a single bulk material with nanoscale domains. However, the characteristic lengthscale of these systems is limited, and the choice of components is restricted to those that are able to undergo microstructural ordering at accessible temperatures. This thesis details routes to overcoming these limitations through the addition of a lithium salt, a blend of homopolymers, or both. Chapter 2 describes a study wherein complex sphere phases such as the Frank-Kasper sigma phase can be observed in otherwise disordered asymmetric block polymers through the addition of a lithium salt. Chapter 3 discusses the development and characterization of a ternary polymer blend of an AB diblock copolymer and A and B homopolymers doped with a lithium salt. Detailed characterization showed that doping blends that are otherwise disordered with lithium salt induced microstructural ordering and largely recovers the phase behavior of traditional ternary polymer blends. A systematic study of the ionic conductivity of the blends at a fixed salt concentration demonstrates that, at a given composition, disordered, yet highly structured blends consistently exhibit better conductivity than polycrystalline morphologies with long range order. Chapter 4 extends the methodology of Chapter 3 and details a systematic study of the effects of cross-linker concentration on the performance of polymer electrolyte membranes produced via polymerization-induced microphase separation that exhibit a highly structured, globally disordered microstructure. Finally, Chapter 5 details efforts to develop a water filtration membrane using a polyethylene template derived from a polymeric bicontinuous microemulsion. Throughout all of this work, the goal is to better understand structure-property relationships at the molecular level in order to

Structural characterization/correlation of calorimetric properties of coal fluids. First annual report, September 1, 1985-August 31, 1986

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

Starling, K.E.; Mallinson, R.G.; Li, M.H.

The objective of this research is to examine the relationship between the calorimetric properties of coal liquids and their molecular functional group composition. Coal liquid samples which have had their calorimetric properties measured are characterized using proton NMR, ir and elemental analysis. These characterizations are then used in a chemical structural model to determine the composition of the coal liquid in terms of the important molecular functional groups. These functional groups are particularly important in determining the intramolecular based properties of a fluid, such as ideal gas heat capacities. Correlational frameworks for heat capacities will then be examined within anmore » existing equation of state methodology to determine an optimal correlation. Also, the optimal recipe for obtaining the characterization/chemical structure information and the sensitivity of the correlation to the characterization and structural model will be examined and determined. 7 refs.« less

Patient-specific academic detailing for smoking cessation

PubMed Central

Jin, Margaret; Gagnon, Antony; Levine, Mitchell; Thabane, Lehana; Rodriguez, Christine; Dolovich, Lisa

2014-01-01

Abstract Objective To describe and to determine the feasibility of a patient-specific academic detailing (PAD) smoking cessation (SC) program in a primary care setting. Design Descriptive cohort feasibility study. Setting Hamilton, Ont. Participants Pharmacists, physicians, nurse practitioners, and their patients. Interventions Integrated pharmacists received basic academic detailing training and education on SC and then delivered PAD to prescribers using structured verbal education and written materials. Data were collected using structured forms. Main outcome measures Five main feasibility criteria were generated based on Canadian academic detailing programs: PAD coordinator time to train pharmacists less than 40 hours; median time of SC education per pharmacist less than 20 hours; median time per PAD session less than 60 minutes for initial visit; percentage of prescribers receiving PAD within 3 months greater than 50%; and number of new SC referrals to pharmacists at 6 months more than 10 patients per 1.0 full-time equivalent (FTE) pharmacist (total of approximately 30 patients). Results Eight pharmacists (5.8 FTE) received basic academic detailing training and education on SC PAD. Forty-eight physicians and 9 nurse practitioners consented to participate in the study. The mean PAD coordinator training time was 29.1 hours. The median time for SC education was 3.1 hours. The median times for PAD sessions were 15 and 25 minutes for an initial visit and follow-up visit, respectively. The numbers of prescribers who had received PAD at 3 and 6 months were 50 of 64 (78.1%) and 57 of 64 (89.1%), respectively. The numbers of new SC referrals at 3 and 6 months were 11 patients per FTE pharmacist (total of 66 patients) and 34 patients per FTE pharmacist (total of 200 patients), respectively. Conclusion This study met the predetermined feasibility criteria with respect to the management, resources, process, and scientific components. Further study is warranted to determine

Detail of sheet steel bulkhead, wharf A, looking northwest ...

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

Detail of sheet steel bulkhead, wharf A, looking northwest - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

View southwest, wharf A, detail of rebuilt section failure ...

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

View southwest, wharf A, detail of rebuilt section failure - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Tree crown structural characterization: A study using terrestrial laser scanning and three-dimensional radiative transfer modeling

NASA Astrophysics Data System (ADS)

Moorthy, Inian

Spectroscopic observational data for vegetated environments, have been coupled with 3D physically-based radiative transfer models for retrievals of biochemical and biophysical indicators of vegetation health and condition. With the recent introduction of Terrestrial Laser Scanning (TLS) units, there now exists a means of rapidly measuring intricate structural details of vegetation canopies, which can also serve as input into 3D radiative transfer models. In this investigation, Intelligent Laser Ranging and Imaging System (ILRIS-3D) data was acquired of individual tree crowns in laboratory, and field-based experiments. The ILRIS-3D uses the Time-Of-Flight (TOF) principle to measure the distances of objects based on the time interval between laser pulse exitance and return, upon reflection from an object. At the laboratory-level, this exploratory study demonstrated and validated innovative approaches for retrieving crown-level estimates of Leaf Area Index (LAI) (r2 = 0.98, rmse = 0.26m2/m2), a critical biophysical parameter for vegetation monitoring and modeling. These methods were implemented and expanded in field experiments conducted in olive (Olea europaea L.) orchards in Cordoba, Spain, where ILRIS-3D observations for 24 structurally-variable trees were made. Robust methodologies were developed to characterize diagnostic architectural parameters, such as tree height (r2 = 0.97, rmse = 0.21m), crown width (r 2 = 0.98, rmse = 0.12m), crown height (r2 = 0.81, rmse = 0.11m), crown volume (r2 = 0.99, rmse = 2.6m3), and LAI (r2 = 0.76, rmse = 0.27m2/ m2). These parameters were subsequently used as direct inputs into the Forest LIGHT (FLIGHT) 3D ray tracing model for characterization of the spectral behavior of the olive crowns. Comparisons between FLIGHT-simulated spectra and measured data showed small differences in the visible (< 3%) and near infrared (< 10%) spectral ranges. These differences between model simulations and measurements were significantly correlated

Standardization of allergen products: 2. Detailed characterization of GMP-produced recombinant Phl p 5.0109 as European Pharmacopoeia reference standard.

PubMed

Himly, M; Nandy, A; Kahlert, H; Thilker, M; Steiner, M; Briza, P; Neubauer, A; Klysner, S; van Ree, R; Buchheit, K-H; Vieths, S; Ferreira, F

2016-04-01

The Biological Standardization Programme of the European Directorate for Quality of Medicines and Healthcare (EDQM) aims at the establishment of well-characterized reference standards based on recombinant allergens and validated assays for the quantification of major allergen content. The objective of this study was to examine the detailed physicochemical and immunological characterization of recombinant Phl p 5.0109, the second available allergen reference standard. Recombinant Phl p 5.0109 PP5ar06007 was produced under GMP conditions and analyzed by an array of physicochemical and immunological methods for identity, quantity, homogeneity, and folding stability in bulk solution, as well as thermal denaturation, aggregation state, and biological activity when formulated for long-time storage. PP5ar06007 revealed as a highly homogeneous, monomeric, well-folded preparation of rPhl p 5.0109, as documented by mass spectrometry, SDS-PAGE, isoelectric focusing, size-exclusion chromatography with light scattering, circular dichroism, and infrared spectroscopy. Upon storage at +4°C, PP5ar06007 retained the monomeric state for at least 2 months. A protein quantity of 1.56 ± 0.03 mg/ml was determined by amino acid analysis in PP5ar06007, and its biological activity was shown to be comparable to natural Phl p 5 in terms of basophil activation and T-cell reactivity. Recombinant Phl p 5.0109 PP5ar06007 was characterized extensively at the physicochemical and immunological level. It revealed to be a highly stable, monomeric, and immunologically equivalent of its natural counterpart. PP5ar06007 is now available as European Pharmacopoeia allergen reference standard for grass pollen products. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of topological structure on complex networks.

PubMed

Nakamura, Ikuo

2003-10-01

Characterizing the topological structure of complex networks is a significant problem especially from the viewpoint of data mining on the World Wide Web. "Page rank" used in the commercial search engine Google is such a measure of authority to rank all the nodes matching a given query. We have investigated the page-rank distribution of the real Web and a growing network model, both of which have directed links and exhibit a power law distributions of in-degree (the number of incoming links to the node) and out-degree (the number of outgoing links from the node), respectively. We find a concentration of page rank on a small number of nodes and low page rank on high degree regimes in the real Web, which can be explained by topological properties of the network, e.g., network motifs, and connectivities of nearest neighbors.

Isolation and structural characterization of the milled wood lignin, dioxane lignin, and cellulolytic lignin preparations from brewer's spent grain.

PubMed

Rencoret, Jorge; Prinsen, Pepijn; Gutiérrez, Ana; Martínez, Ángel T; Del Río, José C

2015-01-21

The structure of the lignin from brewer's spent grain (BSG) has been studied in detail. Three different lignin preparations, the so-called "milled-wood" lignin (MWL), dioxane lignin (DL), and cellulolytic lignin (CEL), were isolated from BSG and then thoroughly characterized by pyrolysis GC/MS, 2D-NMR, and derivatization followed by reductive cleavage (DFRC). The data indicated that BSG lignin presents a predominance of guaiacyl units (syringyl/guaiacyl ratio of 0.4-0.5) with significant amounts of associated p-coumarates and ferulates. The flavone tricin was also present in the lignin from BSG, as also occurred in other grasses. 2D-NMR (HSQC) revealed that the main substructures present are β-O-4' alkyl-aryl ethers (77-79%) followed by β-5' phenylcoumarans (11-13%) and lower amounts of β-β' resinols (5-6%) and 5-5' dibenzodioxocins (3-5%). The results from 2D-NMR (HMBC) and DFRC indicated that p-coumarates are acylating the γ-carbon of lignin side chains and are mostly involved in condensed structures. DFRC analyses also indicated a minor degree of γ-acylation with acetate groups, which takes place preferentially on S lignin (6% of S units are acetylated) over G lignin (only 1% of G units are acetylated).

Structure-guided Protein Transition Modeling with a Probabilistic Roadmap Algorithm.

PubMed

Maximova, Tatiana; Plaku, Erion; Shehu, Amarda

2016-07-07

Proteins are macromolecules in perpetual motion, switching between structural states to modulate their function. A detailed characterization of the precise yet complex relationship between protein structure, dynamics, and function requires elucidating transitions between functionally-relevant states. Doing so challenges both wet and dry laboratories, as protein dynamics involves disparate temporal scales. In this paper we present a novel, sampling-based algorithm to compute transition paths. The algorithm exploits two main ideas. First, it leverages known structures to initialize its search and define a reduced conformation space for rapid sampling. This is key to address the insufficient sampling issue suffered by sampling-based algorithms. Second, the algorithm embeds samples in a nearest-neighbor graph where transition paths can be efficiently computed via queries. The algorithm adapts the probabilistic roadmap framework that is popular in robot motion planning. In addition to efficiently computing lowest-cost paths between any given structures, the algorithm allows investigating hypotheses regarding the order of experimentally-known structures in a transition event. This novel contribution is likely to open up new venues of research. Detailed analysis is presented on multiple-basin proteins of relevance to human disease. Multiscaling and the AMBER ff14SB force field are used to obtain energetically-credible paths at atomistic detail.

A detailed phylogeny for the Methanomicrobiales

NASA Technical Reports Server (NTRS)

Rouviere, P.; Mandelco, L.; Winker, S.; Woese, C. R.

1992-01-01

The small subunit rRNA sequence of twenty archaea, members of the Methanomicrobiales, permits a detailed phylogenetic tree to be inferred for the group. The tree confirms earlier studies, based on far fewer sequences, in showing the group to be divided into two major clusters, temporarily designated the "methanosarcina" group and the "methanogenium" group. The tree also defines phylogenetic relationships within these two groups, which in some cases do not agree with the phylogenetic relationships implied by current taxonomic names--a problem most acute for the genus Methanogenium and its relatives. The present phylogenetic characterization provides the basis for a consistent taxonomic restructuring of this major methanogenic taxon.

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.

Dynamic characterization of contact interactions of micro-robotic leg structures

NASA Astrophysics Data System (ADS)

Ryou, Jeong Hoon; Oldham, Kenn Richard

2014-05-01

Contact dynamics of microelectromechanical systems (MEMS) are typically complicated and it is consequently difficult to model all dynamic characteristics observed in time-domain responses involving impact. This issue becomes worse when a device, such as a mobile micro-robot, is not clamped to a substrate and has a complex mechanical structure. To characterize such a contact interaction situation, two walking micro-robot prototypes are tested having intentionally simple structures with different dimensions (21.2 mm × 16.3 mm × 0.75 mm and 32 mm × 25.4 mm × 4.1 mm) and weights (0.16 and 2.7 g). Contact interaction behaviors are characterized by analyzing experimental data under various excitation signals. A numerical approach was used to derive a novel contact model consisting of a coefficient of restitution matrix that uses modal vibration information. Experimental validation of the simulation model shows that it captures various dynamic features of the contact interaction when simulating leg behavior more accurately than previous contact models, such as single-point coefficient of restitution or compliant ground models. In addition, this paper shows that small-scale forces can be added to the simulation to improve model accuracy, resulting in average errors across driving conditions on the order of 2-6% for bounce frequency, maximum foot height, and average foot height, although there is substantial variation from case to case.

Coupling a distributed hydrological model with detailed forest structural information for large-scale global change impact assessment

NASA Astrophysics Data System (ADS)

Eisner, Stephanie; Huang, Shaochun; Majasalmi, Titta; Bright, Ryan; Astrup, Rasmus; Beldring, Stein

2017-04-01

Forests are recognized for their decisive effect on landscape water balance with structural forest characteristics as stand density or species composition determining energy partitioning and dominant flow paths. However, spatial and temporal variability in forest structure is often poorly represented in hydrological modeling frameworks, in particular in regional to large scale hydrological modeling and impact analysis. As a common practice, prescribed land cover classes (including different generic forest types) are linked to parameter values derived from literature, or parameters are determined by calibration. While national forest inventory (NFI) data provide comprehensive, detailed information on hydrologically relevant forest characteristics, their potential to inform hydrological simulation over larger spatial domains is rarely exploited. In this study we present a modeling framework that couples the distributed hydrological model HBV with forest structural information derived from the Norwegian NFI and multi-source remote sensing data. The modeling framework, set up for the entire of continental Norway at 1 km spatial resolution, is explicitly designed to study the combined and isolated impacts of climate change, forest management and land use change on hydrological fluxes. We use a forest classification system based on forest structure rather than biomes which allows to implicitly account for impacts of forest management on forest structural attributes. In the hydrological model, different forest classes are represented by three parameters: leaf area index (LAI), mean tree height and surface albedo. Seasonal cycles of LAI and surface albedo are dynamically simulated to make the framework applicable under climate change conditions. Based on a hindcast for the pilot regions Nord-Trøndelag and Sør-Trøndelag, we show how forest management has affected regional hydrological fluxes during the second half of the 20th century as contrasted to climate variability.

INTERIOR; DETAIL OF ANTENNA TRUNK OPENING, LOOKING EAST. Naval ...

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

INTERIOR; DETAIL OF ANTENNA TRUNK OPENING, LOOKING EAST. - Naval Computer & Telecommunications Area Master Station, Eastern Pacific, Radio Transmitter Facility Lualualei, Helix House No. 2, Base of Radio Antenna Structure No. 427, Makaha, Honolulu County, HI

Part I: Structural Characterization of Doped Nanostructured Magnesium: Understanding Disorder for Enhanced Hydrogen Absorption Kinetics Part II: Synthesis, Film Deposition, and Characterization of Quaternary Metal Chalcogenide Nanocrystals for Photovoltaic Applications

NASA Astrophysics Data System (ADS)

Braun, Max B.

The production, storage, and subsequent consumption of energy are at the foundation of all human activity and livelihood. The theme of this dissertation is the pursuit of fundamental understanding of the chemistry of materials that are used for energy production and storage. A strong emphasis is placed on a synthetic foundation that allows for systematic investigation into the fundamental chemistry that controls the applicable properties of the materials of interest. This dissertation is written in the "journals format" style--which is accepted by the Graduate School at Colorado State University--and is based on one peer-reviewed publication that has appeared in Chemistry of Materials as well as two manuscripts to be submitted, one to The Journal of Physical Chemistry C, and one to ACS Applied Materials and Interfaces. In order to create a context for these publications, Chapters 1 and 3 provide an overview of the motivations for the projects, and then continue to detail the initial synthetic investigations and considerations for the two projects. In addition to recounting Mg nanocrystals synthetic refinement that was necessary for reproducible hydride kinetic analysis, Chapter 1 also briefly introduces some of the conventional models used for fitting of the hydriding kinetics data. Furthermore, initial investigations into the use of these models for our system are presented. Chapter 2 is a paper to be submitted to The Journal of Physical Chemistry C that describes the local and extended structure characterization of Mg nanocrystals (NCs) with a small amount of nickel added during synthesis. Ni has a dramatic effect on the de/hydriding kinetics of Mg NCs, and this chapter describes the use of a combination of multiple state-of-the-art characterization techniques to gain insight into the structural perturbations due to Ni inclusion in the Mg NCs. This insight is then used to establish the characteristics of Ni inclusion that results in the enhanced hydrogen

Characterizing 3D Vegetation Structure from Space: Mission Requirements

NASA Technical Reports Server (NTRS)

Hall, Forrest G.; Bergen, Kathleen; Blair, James B.; Dubayah, Ralph; Houghton, Richard; Hurtt, George; Kellndorfer, Josef; Lefsky, Michael; Ranson, Jon; Saatchi, Sasan;

Flow structure through pool-riffle sequences and a conceptual model for their sustainability in gravel-bed rivers

Treesearch

D. Caamano; P. Goodwin; J. M. Buffington

2010-01-01

Detailed field measurements and simulations of three-dimensional flow structure were used to develop a conceptual model to explain the sustainability of self-formed pool-riffle sequences in gravel-bed rivers. The analysis was conducted at the Red River Wildlife Management Area in Idaho, USA, and enabled characterization of the flow structure through two consecutive...

Structural insights, protein-ligand interactions and spectroscopic characterization of isoformononetin

NASA Astrophysics Data System (ADS)

Srivastava, Anubha; Singh, Harshita; Mishra, Rashmi; Dev, Kapil; Tandon, Poonam; Maurya, Rakesh

2017-04-01

Isoformononetin, a methoxylated isoflavone present in medicinal plants, has non-estrogenic bone forming effect via differential mitogen-activated protein kinase (MAPK) signaling. Spectroscopic (FT-Raman, FT-IR, UV-vis and NMR spectra) and quantum chemical calculations using density functional theory (DFT) and 6-311++G(d,p) as a large basis set have been employed to study the structural and electronic properties of isoformononetin. A detailed conformational analysis is performed to determine the stability among conformers and the various possibilities of intramolecular hydrogen bonding formation. Molecular docking studies with different protein kinases were performed on isoformononetin and previously studied isoflavonoid, formononetin in order to understand their inhibitory nature and the effect of functional groups on osteogenic or osteoporosis associated proteins. It is found that the oxygen atoms of methoxy, hydroxyl groups attached to phenyl rings R1, R3 and carbonyl group attached to pyran ring R2, play a major role in binding with the protein kinases that is responsible for the osteoporosis; however, no hydrophobic interactions are observed between rings of ligand and protein. The electronic properties such as HOMO and LUMO energies were determined by time-dependent TD-DFT which predict that conformer II is a little bit more stable and chemically low reactive than conformer I of isoformononetin. To estimate the structure-activity relationship, the molecular electrostatic potential (MEP) surface map, and reactivity descriptors are calculated from the optimized geometry of the molecule. From these results, it is also found that isoformononetin is kinetically more stable, less toxic, weak electrophile and chemically less reactive than formononetin. The atoms in molecules and natural bond orbital analysis are applied for the detailed analysis of intra and intermolecular hydrogen bonding interactions.

Detailed characterization of the 1087 MeV/nucleon iron-56 beam used for radiobiology at the alternating gradient synchrotron

NASA Technical Reports Server (NTRS)

Zeitlin, C.; Heilbronn, L.; Miller, J.

1998-01-01

We report beam characterization and dosimetric measurements made using a 56Fe beam extracted from the Brookhaven National Laboratory Alternating Gradient Synchrotron (AGS) with a kinetic energy of 1087 MeV/nucleon. The measurements reveal that the depth-dose distribution of this beam differs significantly from that obtained with a 600 MeV/nucleon iron beam used in several earlier radiobiology experiments at the Lawrence Berkeley National Laboratory's BEVALAC. We present detailed measurements of beam parameters relevant for radiobiology, including track- and dose-averaged linear energy transfer (LET), fragment composition and LET spectra measured behind sample holders used in irradiations of biological samples. We also report measurements of fluence behind three depths (1.94, 4.68 and 9.35 g cm(-2)) of polyethylene targets with the 1087 MeV/nucleon beam, and behind 1.94 g cm(-2) of polyethylene with a 610 MeV/nucleon beam delivered by the AGS. These results are compared to earlier measurements with the 600 MeV/nucleon beam at the BEVALAC.

Preparation, characterization and crystal structures of three salts of the quaterpyridine ligand

NASA Astrophysics Data System (ADS)

Ciesielski, Artur; Stefankiewicz, Artur R.; Patroniak, Violetta; Kubicki, Maciej

2009-07-01

As a result of a reaction between 6,6'''-dimethyl-2,2':6',2'':6'',2'''-quaterpyridine C 22H 18N 4 and lanthanide(III) salts, compounds, [C 22H 20N 4] 2+·2(CF 3SO 3) - ( 1) and [C 22H 20N 4] 2+·2(ClO 4) - ( 2), have been obtained. They were characterized by spectroscopic techniques (ESI-MS, NMR, IR), elemental analysis, and their formulae were confirmed on the basis of X-ray crystallography. It turned out that the perchlorate crystallizes as two solvates: with acetonitrile and disordered water molecules. These are the first structural characterization of a 6,6'″-dimethyl-2,2':6',2″:6″,2'″-quaterpyridinium dication. Due to the intramolecular hydrogen bond it adopts the previously unobserved cis/trans/cis conformation. In all three crystals the dications have C i symmetry, they occupy the special positions in their respective space groups. In the crystal structures the π-π stacking and weak hydrogen bonds add directionality to the dominating electrostatic interactions between cations and anions.

Magnetic nanocomposites based on phosphorus-containing polymers—structural characterization and thermal analysis

NASA Astrophysics Data System (ADS)

Alosmanov, R. M.; Szuwarzyński, M.; Schnelle-Kreis, J.; Matuschek, G.; Magerramov, A. M.; Azizov, A. A.; Zimmermann, R.; Zapotoczny, S.

2018-04-01

Fabrication of magnetic nanocomposites containing iron oxide nanoparticles formed in situ within a phosphorus-containing polymer matrix as well as its structural characterization and its thermal degradation is reported here. Comparative structural studies of the parent polymer and nanocomposites were performed using FTIR spectroscopy, x-ray diffraction, and atomic force microscopy. The results confirmed the presence of dispersed iron oxide magnetic nanoparticles in the polymer matrix. The formed composite combines the properties of porous polymer carriers and magnetic particles enabling easy separation and reapplication of such polymeric carriers used in, for example, catalysis or environmental remediation. Studies on thermal degradation of the composites revealed that the process proceeds in three stages while a significant influence of the embedded magnetic particles on that process was observed in the first two stages. Magnetic force microscopy studies revealed that nanocomposites and its calcinated form have strong magnetic properties. The obtained results provide a comprehensive characterization of magnetic nanocomposites and the products of their calcination that are important for their possible applications as sorbents (regeneration conditions, processing temperature, disposal, etc).

Toward structural elucidation of the gamma-secretase complex

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

Li, H.; Wolfe, M. S.; Selkoe, D. J.

2009-03-11

{gamma}-Secretase is an intramembrane protease complex that mediates the Notch signaling pathway and the production of amyloid {beta}-proteins. As such, this enzyme has emerged as an important target for development of novel therapeutics for Alzheimer disease and cancer. Great progress has been made in the identification and characterization of the membrane complex and its biological functions. One major challenge now is to illuminate the structure of this fascinating and important protease at atomic resolution. Here, we review recent progress on biochemical and biophysical probing of the structure of the four-component complex and discuss obstacles and potential pathways toward elucidating itsmore » detailed structure.« less

Structural variability of E. coli thioredoxin captured in the crystal structures of single-point mutants

PubMed Central

Noguera, Martín E.; Vazquez, Diego S.; Ferrer-Sueta, Gerardo; Agudelo, William A.; Howard, Eduardo; Rasia, Rodolfo M.; Manta, Bruno; Cousido-Siah, Alexandra; Mitschler, André; Podjarny, Alberto; Santos, Javier

2017-01-01

Thioredoxin is a ubiquitous small protein that catalyzes redox reactions of protein thiols. Additionally, thioredoxin from E. coli (EcTRX) is a widely-used model for structure-function studies. In a previous paper, we characterized several single-point mutants of the C-terminal helix (CTH) that alter global stability of EcTRX. However, spectroscopic signatures and enzymatic activity for some of these mutants were found essentially unaffected. A comprehensive structural characterization at the atomic level of these near-invariant mutants can provide detailed information about structural variability of EcTRX. We address this point through the determination of the crystal structures of four point-mutants, whose mutations occurs within or near the CTH, namely L94A, E101G, N106A and L107A. These structures are mostly unaffected compared with the wild-type variant. Notably, the E101G mutant presents a large region with two alternative traces for the backbone of the same chain. It represents a significant shift in backbone positions. Enzymatic activity measurements and conformational dynamics studies monitored by NMR and molecular dynamic simulations show that E101G mutation results in a small effect in the structural features of the protein. We hypothesize that these alternative conformations represent samples of the native-state ensemble of EcTRX, specifically the magnitude and location of conformational heterogeneity. PMID:28181556

Structural variability of E. coli thioredoxin captured in the crystal structures of single-point mutants

NASA Astrophysics Data System (ADS)

Noguera, Martín E.; Vazquez, Diego S.; Ferrer-Sueta, Gerardo; Agudelo, William A.; Howard, Eduardo; Rasia, Rodolfo M.; Manta, Bruno; Cousido-Siah, Alexandra; Mitschler, André; Podjarny, Alberto; Santos, Javier

2017-02-01

Thioredoxin is a ubiquitous small protein that catalyzes redox reactions of protein thiols. Additionally, thioredoxin from E. coli (EcTRX) is a widely-used model for structure-function studies. In a previous paper, we characterized several single-point mutants of the C-terminal helix (CTH) that alter global stability of EcTRX. However, spectroscopic signatures and enzymatic activity for some of these mutants were found essentially unaffected. A comprehensive structural characterization at the atomic level of these near-invariant mutants can provide detailed information about structural variability of EcTRX. We address this point through the determination of the crystal structures of four point-mutants, whose mutations occurs within or near the CTH, namely L94A, E101G, N106A and L107A. These structures are mostly unaffected compared with the wild-type variant. Notably, the E101G mutant presents a large region with two alternative traces for the backbone of the same chain. It represents a significant shift in backbone positions. Enzymatic activity measurements and conformational dynamics studies monitored by NMR and molecular dynamic simulations show that E101G mutation results in a small effect in the structural features of the protein. We hypothesize that these alternative conformations represent samples of the native-state ensemble of EcTRX, specifically the magnitude and location of conformational heterogeneity.

Size-dependent characterization of embedded Ge nanocrystals: Structural and thermal properties

NASA Astrophysics Data System (ADS)

Araujo, L. L.; Giulian, R.; Sprouster, D. J.; Schnohr, C. S.; Llewellyn, D. J.; Kluth, P.; Cookson, D. J.; Foran, G. J.; Ridgway, M. C.

2008-09-01

A combination of conventional and synchrotron-based techniques has been used to characterize the size-dependent structural and thermal properties of Ge nanocrystals (NCs) embedded in a silica (a-SiO2) matrix. Ge NC size distributions with four different diameters ranging from 4.0 to 9.0 nm were produced by ion implantation and thermal annealing as characterized with small-angle x-ray scattering and transmission electron microscopy. The NCs were well represented by the superposition of bulklike crystalline and amorphous environments, suggesting the formation of an amorphous layer separating the crystalline NC core and the a-SiO2 matrix. The amorphous fraction was quantified with x-ray-absorption near-edge spectroscopy and increased as the NC diameter decreased, consistent with the increase in surface-to-volume ratio. The structural parameters of the first three nearest-neighbor shells were determined with extended x-ray-absorption fine-structure (EXAFS) spectroscopy and evolved linearly with inverse NC diameter. Specifically, increases in total disorder, interatomic distance, and the asymmetry in the distribution of distances were observed as the NC size decreased, demonstrating that finite-size effects govern the structural properties of embedded Ge NCs. Temperature-dependent EXAFS measurements in the range of 15-300 K were employed to probe the mean vibrational frequency and the variation of the interatomic distance distribution (mean value, variance, and asymmetry) with temperature for all NC distributions. A clear trend of increased stiffness (higher vibrational frequency) and decreased thermal expansion with decreasing NC size was evident, confirming the close relationship between the variation of structural and thermal/vibrational properties with size for embedded Ge NCs. The increase in surface-to-volume ratio and the presence of an amorphous Ge layer separating the matrix and crystalline NC core are identified as the main factors responsible for the observed

Influence of the segmentation on the characterization of cerebral networks of structural damage for patients with disorders of consciousness

NASA Astrophysics Data System (ADS)

Martínez, Darwin; Mahalingam, Jamuna J.; Soddu, Andrea; Franco, Hugo; Lepore, Natasha; Laureys, Steven; Gómez, Francisco

2015-01-01

Disorders of consciousness (DOC) are a consequence of a variety of severe brain injuries. DOC commonly results in anatomical brain modifications, which can affect cortical and sub-cortical brain structures. Postmortem studies suggest that severity of brain damage correlates with level of impairment in DOC. In-vivo studies in neuroimaging mainly focus in alterations on single structures. Recent evidence suggests that rather than one, multiple brain regions can be simultaneously affected by this condition. In other words, DOC may be linked to an underlying cerebral network of structural damage. Recently, geometrical spatial relationships among key sub-cortical brain regions, such as left and right thalamus and brain stem, have been used for the characterization of this network. This approach is strongly supported on automatic segmentation processes, which aim to extract regions of interests without human intervention. Nevertheless, patients with DOC usually present massive structural brain changes. Therefore, segmentation methods may highly influence the characterization of the underlying cerebral network structure. In this work, we evaluate the level of characterization obtained by using the spatial relationships as descriptor of a sub-cortical cerebral network (left and right thalamus) in patients with DOC, when different segmentation approaches are used (FSL, Free-surfer and manual segmentation). Our results suggest that segmentation process may play a critical role for the construction of robust and reliable structural characterization of DOC conditions.

Synchrotron X-ray scattering characterization of the molecular structures of star polystyrenes with varying numbers of arms.

PubMed

Jin, Sangwoo; Higashihara, Tomoya; Jin, Kyeong Sik; Yoon, Jinhwan; Rho, Yecheol; Ahn, Byungcheol; Kim, Jehan; Hirao, Akira; Ree, Moonhor

2010-05-20

We have synthesized well-defined multiarmed star polystyrenes, with 6, 9, 17, 33, and 57 arms, and studied their molecular shapes and structural characteristics in a good solvent (tetrahydrofuran at 25 degrees C) and in a theta (Theta) solvent (cyclohexane at 35 degrees C) by small-angle X-ray scattering (SAXS) using a synchrotron radiation source. Analysis of the SAXS data provided a detailed characterization of the molecular shapes, including the contributions of the blob morphology of the arms, the radius of gyration, the paired distance distribution, the radial electron density distribution, and the Zimm-Stockmayer and Roovers g-factor, for the multiarmed star polystyrenes. In particular, the molecular shapes of the star polystyrenes were found to change from a fuzzy ellipsoid, for the 6-armed polystyrene, to a fuzzy sphere, for the 57-armed polystyrene, with an increasing number of arms. The ellipsoidal character of the star polystyrenes with fewer arms may originate from the extended anisotropically branched architecture at the center of the molecule. The arms of the star polystyrenes were found to be more extended than those of the linear polystyrenes. Furthermore, the degree of chain extension in the arms increased with the number of arms.

Structural and optical characterization of GaAs nano-crystals selectively grown on Si nano-tips by MOVPE.

PubMed

Skibitzki, Oliver; Prieto, Ivan; Kozak, Roksolana; Capellini, Giovanni; Zaumseil, Peter; Arroyo Rojas Dasilva, Yadira; Rossell, Marta D; Erni, Rolf; von Känel, Hans; Schroeder, Thomas

2017-03-01

We present the nanoheteroepitaxial growth of gallium arsenide (GaAs) on nano-patterned silicon (Si) (001) substrates fabricated using a CMOS technology compatible process. The selective growth of GaAs nano-crystals (NCs) was achieved at 570 °C by MOVPE. A detailed structure and defect characterization study of the grown nano-heterostructures was performed using scanning transmission electron microscopy, x-ray diffraction, micro-Raman, and micro-photoluminescence (μ-PL) spectroscopy. The results show single-crystalline, nearly relaxed GaAs NCs on top of slightly, by the SiO 2 -mask compressively strained Si nano-tips (NTs). Given the limited contact area, GaAs/Si nanostructures benefit from limited intermixing in contrast to planar GaAs films on Si. Even though a few growth defects (e.g. stacking faults, micro/nano-twins, etc) especially located at the GaAs/Si interface region were detected, the nanoheterostructures show intensive light emission, as investigated by μ-PL spectroscopy. Achieving well-ordered high quality GaAs NCs on Si NTs may provide opportunities for superior electronic, photonic, or photovoltaic device performances integrated on the silicon technology platform.

Novel functionalized pyridine-containing DTPA-like ligand. Synthesis, computational studies and characterization of the corresponding Gd(III) complex.

PubMed

Artali, Roberto; Botta, Mauro; Cavallotti, Camilla; Giovenzana, Giovanni B; Palmisano, Giovanni; Sisti, Massimo

2007-08-07

A novel pyridine-containing DTPA-like ligand, carrying additional hydroxymethyl groups on the pyridine side-arms, was synthesized in 5 steps. The corresponding Gd(III) complex, potentially useful as an MRI contrast agent, was prepared and characterized in detail by relaxometric methods and its structure modeled by computational methods.

Conducting Reflective, Hands-On Research with Advanced Characterization Instruments: A High-Level Undergraduate Practical Exploring Solid-State Polymorphism

ERIC Educational Resources Information Center

Coles, S. J.; Mapp, L. K.

2016-01-01

An undergraduate practical exercise has been designed to provide hands-on, instrument-based experience of advanced characterization techniques. A research experience approach is taken, centered around the concept of solid-state polymorphism, which requires a detailed knowledge of molecular and crystal structure to be gained by advanced analytical…

Revealing Structural Details of SiCO Ceramics with GIPAW Calculations of Model Structures and Analysis of Experimental 29Si Nuclear Magnetic Resonance Spectroscopy

NASA Astrophysics Data System (ADS)

Nimmo, John; Kroll, Peter

2015-03-01

The occurrence of the various SiCxO4-x (1 <=x <=4) mixed tetrahedra in silicon oxycarbide (SiCO) is often quantified by means of experimental 29Si nuclear magnetic resonance. The structural centers are assigned to individual peaks in the spectrum, which can be integrated to give the relative populations. Using a recently-developed method, we show that is is also possible to recover information on the connectivity of these tetrahedra. By combining a huge library of model structures an GIPAW calculations, we show that simple relations exist between the Si-O-Si linking angles and the 29Si NMR chemical shift. In this work, we perform detailed analyses of SiCO 29Si NMR spectra available in literature. We extract angular distributions in agreement with the experimental X-ray and neutron diffraction data. Furthermore, in glasses with large amounts of so-called ``free'' carbon, we observe a significant portion of the {Si}O4 tetrahedra which have disproportionately large angles. These angles indicate the presence of internal SiO2 surfaces or cages-like voids, similar to those found in zeolites or clathrates. This analysis suggests that in SiCO, the ``free'' carbon is incorporated into these voids, which produces strain on the bonding angles of the surrounding host glass.

Structural and Biochemical Characterization of a Novel Aminopeptidase from Human Intestine

DOE PAGES

Tykvart, Jan; Bařinka, Cyril; Svoboda, Michal; ...

2015-03-09

N-acetylated α-linked acidic dipeptidase-like protein (NAALADase L), encoded by the NAALADL1 gene, is a close homolog of glutamate carboxypeptidase II, a metallopeptidase that has been intensively studied as a target for imaging and therapy of solid malignancies and neuropathologies. However, neither the physiological functions nor structural features of NAALADase L are known at present. In this paper, we report a thorough characterization of the protein product of the human NAALADL1 gene, including heterologous overexpression and purification, structural and biochemical characterization, and analysis of its expression profile. By solving the NAALADase L x-ray structure, we provide the first experimental evidence thatmore » it is a zinc-dependent metallopeptidase with a catalytic mechanism similar to that of glutamate carboxypeptidase II yet distinct substrate specificity. A proteome-based assay revealed that the NAALADL1 gene product possesses previously unrecognized aminopeptidase activity but no carboxy- or endopeptidase activity. These findings were corroborated by site-directed mutagenesis and identification of bestatin as a potent inhibitor of the enzyme. Analysis of NAALADL1 gene expression at both the mRNA and protein levels revealed the small intestine as the major site of protein expression and points toward extensive alternative splicing of the NAALADL1 gene transcript. Taken together, our data imply that the NAALADL1 gene product's primary physiological function is associated with the final stages of protein/peptide digestion and absorption in the human digestive system. Finally, based on these results, we suggest a new name for this enzyme: human ileal aminopeptidase (HILAP).« less

Nonlinear characterization of a bolted, industrial structure using a modal framework

NASA Astrophysics Data System (ADS)

Roettgen, Daniel R.; Allen, Matthew S.

2017-02-01

This article presents measurements from a sub assembly of an off-the-shelf automotive exhaust system containing a bolted-flange connection and uses a recently proposed modal framework to develop a nonlinear dynamic model for the structure. The nonlinear identification and characterization methods used are reviewed to highlight the strengths of the current approach and the areas where further development is needed. This marks the first use of these new testing and nonlinear identification tools, and the associated modal framework, on production hardware with a realistic joint and realistic torque levels. To screen the measurements for nonlinearities, we make use of a time frequency analysis routine designed for transient responses called the zeroed early-time fast Fourier transform (ZEFFT). This tool typically reveals the small frequency shifts and distortions that tend to occur near each mode that is affected by the nonlinearity. The damping in this structure is found to be significantly nonlinear and a Hilbert transform is used to characterize the damping versus amplitude behavior. A model is presented that captures these effects for each mode individually (e.g. assuming negligible nonlinear coupling between modes), treating each mode as a single degree-of-freedom oscillator with a spring and viscous damping element in parallel with a four parameter Iwan model. The parameters of this model are identified for each of the structure's modes that exhibited nonlinearity and the resulting nonlinear model is shown to capture the stiffness and damping accurately over a large range of response amplitudes.

Interaction of chromatin with NaCl and MgCl2. Solubility and binding studies, transition to and characterization of the higher-order structure.

PubMed

Ausio, J; Borochov, N; Seger, D; Eisenberg, H

1984-08-15

Chicken erythrocyte chromatin containing histones H1 and H5 was carefully separated into a number of well-characterized fractions. A distinction could be made between chromatin insoluble in NaCl above about 80 mM, and chromatin soluble at all NaCl concentrations. Both chromatin forms were indistinguishable electrophoretically and both underwent the transition from the low salt "10 nm" coil to the "30 nm" higher-order structure solenoid by either raising the MgCl2 concentration to about 0.3 mM or the NaCl concentration to about 75 mM. The transitions were examined in detail by elastic light-scattering procedures. It could be shown that the 10 nm form is a flexible coil. For the 30 nm solenoid, the assumption of a rigid cylindrical structure was in good agreement with 5.7 nucleosomes per helical turn. However, disagreement of calculated frictional parameters with values derived from quasielastic light-scattering and sedimentation introduced the possibility that the higher-order structure, under these conditions, is more extended, flexible, or perhaps a mixture of structures. Values for density and refractive index increments of chromatin are also given. To understand the interaction of chromatin with NaCl and with MgCl2, a number of experiments were undertaken to study solubility, precipitation, conformational transitions and binding of ions over a wide range of experimental conditions, including chromatin concentration.

Structural characterization and IgE epitope analysis of arginine kinase from Scylla paramamosain

USDA-ARS?s Scientific Manuscript database

Arginine kinase (AK) has been reported as the pan-allergen of shellfish, however, there is limited information about its IgE epitopes and structural characteristics. In this study, AK from Scylla paramamosain was purified and characterized. The purified AK was a glycoprotein with the molecular weigh...

Biochemical and structural characterization of Cryptosporidium parvum Lactate dehydrogenase.

PubMed

Cook, William J; Senkovich, Olga; Hernandez, Agustin; Speed, Haley; Chattopadhyay, Debasish

2015-03-01

The protozoan parasite Cryptosporidium parvum causes waterborne diseases worldwide. There is no effective therapy for C. parvum infection. The parasite depends mainly on glycolysis for energy production. Lactate dehydrogenase is a major regulator of glycolysis. This paper describes the biochemical characterization of C. parvum lactate dehydrogenase and high resolution crystal structures of the apo-enzyme and four ternary complexes. The ternary complexes capture the enzyme bound to NAD/NADH or its 3-acetylpyridine analog in the cofactor binding pocket, while the substrate binding site is occupied by one of the following ligands: lactate, pyruvate or oxamate. The results reveal distinctive features of the parasitic enzyme. For example, C. parvum lactate dehydrogenase prefers the acetylpyridine analog of NADH as a cofactor. Moreover, it is slightly less sensitive to gossypol inhibition compared with mammalian lactate dehydrogenases and not inhibited by excess pyruvate. The active site loop and the antigenic loop in C. parvum lactate dehydrogenase are considerably different from those in the human counterpart. Structural features and enzymatic properties of C. parvum lactate dehydrogenase are similar to enzymes from related parasites. Structural comparison with malate dehydrogenase supports a common ancestry for the two genes. Copyright © 2014 Elsevier B.V. All rights reserved.

Antifreeze (glyco)protein mimetic behavior of poly(vinyl alcohol): detailed structure ice recrystallization inhibition activity study.

PubMed

Congdon, Thomas; Notman, Rebecca; Gibson, Matthew I

2013-05-13

This manuscript reports a detailed study on the ability of poly(vinyl alcohol) to act as a biomimetic surrogate for antifreeze(glyco)proteins, with a focus on the specific property of ice-recrystallization inhibition (IRI). Despite over 40 years of study, the underlying mechanisms that govern the action of biological antifreezes are still poorly understood, which is in part due to their limited availability and challenging synthesis. Poly(vinyl alcohol) (PVA) has been shown to display remarkable ice recrystallization inhibition activity despite its major structural differences to native antifreeze proteins. Here, controlled radical polymerization is used to synthesize well-defined PVA, which has enabled us to obtain the first quantitative structure-activity relationships, to probe the role of molecular weight and comonomers on IRI activity. Crucially, it was found that IRI activity is "switched on" when the polymer chain length increases from 10 and 20 repeat units. Substitution of the polymer side chains with hydrophilic or hydrophobic units was found to diminish activity. Hydrophobic modifications to the backbone were slightly more tolerated than side chain modifications, which implies an unbroken sequence of hydroxyl units is necessary for activity. These results highlight that, although hydrophobic domains are key components of IRI activity, the random inclusion of addition hydrophobic units does not guarantee an increase in activity and that the actual polymer conformation is important.

Structural characterization and antimicrobial activities of transition metal complexes of a hydrazone ligand

NASA Astrophysics Data System (ADS)

Bakale, Raghavendra P.; Naik, Ganesh N.; Machakanur, Shrinath S.; Mangannavar, Chandrashekhar V.; Muchchandi, Iranna S.; Gudasi, Kalagouda B.

2018-02-01

A hydrazone ligand has been synthesized by the condensation of 2-nitrobenzaldehyde and hydralazine, and its Co(II), Ni(II), Cu(II) and Zn(II) complexes have been reported. Structural characterization of the ligand and its metal complexes has been performed by various spectroscopic [IR, NMR, UV-Vis, Mass], thermal and other physicochemical methods. The structure of the ligand and its Ni(II) complex has been characterized by single crystal X-ray diffraction studies. All the synthesized compounds have been screened for in vitro antimicrobial activity. The antibacterial activity is tested against Gram-positive strains Enterococcus faecalis, Streptococcus mutans and Staphylococcus aureus and Gram-negative strains Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae using ciprofloxacin as the reference standard. Antifungal activity is tested against Candida albicans, Aspergillus fumigatus and Aspergillus niger using ketoconazole as the reference standard. The minimum inhibitory concentration (MIC) was determined for test compounds as well as for reference standard. Ligand, Cu(II) and Zn(II) complexes have shown excellent activity against Candida albicans.

Characterization of structure and thermophysical properties of three ESR slags

NASA Astrophysics Data System (ADS)

Plotkowski, A.; deBarbadillo, J.; Krane, Matthew J. M.

2016-07-01

The structure and properties of electroslag remelting (ESR) slags were characterized. Slags samples of three compositions were obtained from industrial remelting processes at Special Metals Corporation and from casting in a laboratory vacuum induction melter. The structure of the slag samples was observed using optical and electron microscopy, and phases were identified and their relative amounts quantified using X-ray diffraction. Laser flash thermal diffusivity, density, and differential scanning calorimetry measurements for specific heat were performed to determine the bulk thermal conductivity of the samples. Sample porosity was measured as a function of depth using a serial sectioning technique, and a onedimensional computational model was developed to estimate the thermal conductivity of the fully dense slags. These results are discussed in context with previous studies, and opportunities for future research are identified. AFRL Case Number: 88ABW-2015-1871.

X-ray Absorption Fine Structure (XAFS) Studies of Oxide Glasses—A 45-Year Overview

PubMed Central

Zanotto, Edgar Dutra

2018-01-01

X-ray Absorption Fine Structure (XAFS) spectroscopy has been widely used to characterize the short-range order of glassy materials since the theoretical basis was established 45 years ago. Soon after the technique became accessible, mainly due to the existence of Synchrotron laboratories, a wide range of glassy materials was characterized. Silicate glasses have been the most studied because they are easy to prepare, they have commercial value and are similar to natural glasses, but borate, germanate, phosphate, tellurite and other less frequent oxide glasses have also been studied. In this manuscript, we review reported advances in the structural characterization of oxide-based glasses using this technique. A focus is on structural characterization of transition metal ions, especially Ti, Fe, and Ni, and their role in different properties of synthetic oxide-based glasses, as well as their important function in the formation of natural glasses and magmas, and in nucleation and crystallization. We also give some examples of XAFS applications for structural characterization of glasses submitted to high pressure, glasses used to store radioactive waste and medieval glasses. This updated, comprehensive review will likely serve as a useful guide to clarify the details of the short-range structure of oxide glasses. PMID:29382102

[Spectrum characterization and fine structure of copper phthalocyanine-doped TiO2 microcavities].

PubMed

Liu, Cheng-lin; Zhang, Xin-yi; Zhong, Ju-hua; Zhu, Yi-hua; He, Bo; Wei, Shi-qiang

2007-10-01

Copper phthalocyanine-doped TiO2 microcavities were fabricated by chemistry method. Their spectrum characterization was studied by Fourier transform infrared (FTIR) and Raman spectroscopy, and their fine structure was analyzed by X-ray absorption fine structure (XAFS). The results show that there is interaction of copper phthalocyanine (CuPc) and TiO2 microcavities after TiO2 microcavities was doped with CuPc. For example, there is absorption at 900.76 cm(-1) in FTIR spectra, and the "red shift" of both OH vibration at 3392.75 cm(-1) and CH vibration at 2848.83 cm(-1). There exist definite peak shifts and intensity changes in infrared absorption in the C-C or C-N vibration in the planar phthalocyanine ring, the winding vibration of C-H inside and C-N outside plane of benzene ring. In Raman spectrum, there are 403.4, 592.1 and 679.1 cm(-1) characterized peaks of TiO2 in CuPc-doped TiO2 microcavities, but their wave-numbers show shifts to anatase TiO2. The vibration peaks at 1586.8 and 1525.6 cm(-1) show that there exists the composite material of CuPc and TiO2. These changes are related to the plane tropism of the molecule structure of copper phthalocyanine. XAFS showed tetrahedron TiO4 structure of Ti in TiO2 microcavities doped with copper phthalocyanine, and the changes of inner "medial distances" and the surface structure of TiO2 microcavities.

Atomic-level characterization of the structural dynamics of proteins.

PubMed

Shaw, David E; Maragakis, Paul; Lindorff-Larsen, Kresten; Piana, Stefano; Dror, Ron O; Eastwood, Michael P; Bank, Joseph A; Jumper, John M; Salmon, John K; Shan, Yibing; Wriggers, Willy

2010-10-15

Molecular dynamics (MD) simulations are widely used to study protein motions at an atomic level of detail, but they have been limited to time scales shorter than those of many biologically critical conformational changes. We examined two fundamental processes in protein dynamics--protein folding and conformational change within the folded state--by means of extremely long all-atom MD simulations conducted on a special-purpose machine. Equilibrium simulations of a WW protein domain captured multiple folding and unfolding events that consistently follow a well-defined folding pathway; separate simulations of the protein's constituent substructures shed light on possible determinants of this pathway. A 1-millisecond simulation of the folded protein BPTI reveals a small number of structurally distinct conformational states whose reversible interconversion is slower than local relaxations within those states by a factor of more than 1000.

Syntheses, crystal structures and characterization of nitrogen-rich salts based on bis (1H-tetrazol-5-yl) methanone oxime

NASA Astrophysics Data System (ADS)

Lin, Xinyu; Guo, Weiming; Zhang, Tianhe; Huang, Jingru; Tong, Yi; Zhang, Tonglai

2017-08-01

Two nitrogen-rich energetic salts (NH4)2(bto) (1) and (NH3OH)2(bto)·H2O (2) [H2bto = Bis (1H-tetrazol-5-yl) methanone oxime] were synthesized by an improved method in which water was used as solvent. These compounds were characterized by FT-IR spectroscopy, elemental analysis and single crystal X-ray diffraction. Their crystal structures were confirmed to belong to monoclinic system with space group P21 for 1 and Pc for 2, respectively. The detailed thermal behaviours were investigated by using differential scanning calorimetry (DSC) and thermogravimetric method (TG) (decomposition temperature >250 °C). The enthalpies of formation were calculated through the experimental values of combustion enthalpy. In addition, the sensitivities toward impact and friction were tested with standard methods, and those results indicated that two compounds are all insensitive (impact >40 J and friction >360 N). In short, both of the compounds show potential usages as energetic materials. The improved process opens a door for exploring nitrogen-rich salts based on Bis (1H-tetrazol-5-yl) methanone oxime.

10. Detail view of pendant lamps, laminated arch beams and ...

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

10. Detail view of pendant lamps, laminated arch beams and ceiling structure, facing north - Mountain Home Air Force Base, Base Chapel, 350 Willow Street, Cantonment Area, Mountain Home, Elmore County, ID

Characterization, Modeling, and Failure Analysis of Composite Structure Materials under Static and Dynamic Loading

NASA Astrophysics Data System (ADS)

Werner, Brian Thomas

Composite structures have long been used in many industries where it is advantageous to reduce weight while maintaining high stiffness and strength. Composites can now be found in an ever broadening range of applications: sporting equipment, automobiles, marine and aerospace structures, and energy production. These structures are typically sandwich panels composed of fiber reinforced polymer composite (FRPC) facesheets which provide the stiffness and the strength and a low density polymeric foam core that adds bending rigidity with little additional weight. The expanding use of composite structures exposes them to high energy, high velocity dynamic loadings which produce multi-axial dynamic states of stress. This circumstance can present quite a challenge to designers, as composite structures are highly anisotropic and display properties that are sensitive to loading rates. Computer codes are continually in development to assist designers in the creation of safe, efficient structures. While the design of an optimal composite structure is more complex, engineers can take advantage of the effect of enhanced energy dissipation displayed by a composite when loaded at high strain rates. In order to build and verify effective computer codes, the underlying assumptions must be verified by laboratory experiments. Many of these codes look to use a micromechanical approach to determine the response of the structure. For this, the material properties of the constituent materials must be verified, three-dimensional constitutive laws must be developed, and failure of these materials must be investigated under static and dynamic loading conditions. In this study, simple models are sought not only to ease their implementation into such codes, but to allow for efficient characterization of new materials that may be developed. Characterization of composite materials and sandwich structures is a costly, time intensive process. A constituent based design approach evaluates potential

Structural, Mechanistic, and Antigenic Characterization of the Human Astrovirus Capsid

PubMed Central

York, Royce L.; Yousefi, Payam A.; Bogdanoff, Walter; Haile, Sara; Tripathi, Sarvind

2015-01-01

ABSTRACT Human astroviruses (HAstVs) are nonenveloped, positive-sense, single-stranded RNA viruses that are a leading cause of viral gastroenteritis. HAstV particles display T=3 icosahedral symmetry formed by 180 copies of the capsid protein (CP), which undergoes proteolytic maturation to generate infectious HAstV particles. Little is known about the molecular features that govern HAstV particle assembly, maturation, infectivity, and immunogenicity. Here we report the crystal structures of the two main structural domains of the HAstV CP: the core domain at 2.60-Å resolution and the spike domain at 0.95-Å resolution. Fitting of these structures into the previously determined 25-Å-resolution electron cryomicroscopy density maps of HAstV allowed us to characterize the molecular features on the surfaces of immature and mature T=3 HAstV particles. The highly electropositive inner surface of HAstV supports a model in which interaction of the HAstV CP core with viral RNA is a driving force in T=3 HAstV particle formation. Additionally, mapping of conserved residues onto the HAstV CP core and spike domains in the context of the immature and mature HAstV particles revealed dramatic changes to the exposure of conserved residues during virus maturation. Indeed, we show that antibodies raised against mature HAstV have reactivity to both the HAstV CP core and spike domains, revealing for the first time that the CP core domain is antigenic. Together, these data provide new molecular insights into HAstV that have practical applications for the development of vaccines and antiviral therapies. IMPORTANCE Astroviruses are a leading cause of viral diarrhea in young children, immunocompromised individuals, and the elderly. Despite the prevalence of astroviruses, little is known at the molecular level about how the astrovirus particle assembles and is converted into an infectious, mature virus. In this paper, we describe the high-resolution structures of the two main astrovirus

Structural characterization of a first-generation articulated-truss joint for space crane application

NASA Technical Reports Server (NTRS)

Sutter, Thomas R.; Wu, K. Chauncey; Riutort, Kevin T.; Laufer, Joseph B.; Phelps, James E.

1992-01-01

A first-generation space crane articulated-truss joint was statically and dynamically characterized in a configuration that approximated an operational environment. The articulated-truss joint was integrated into a test-bed for structural characterization. Static characterization was performed by applying known loads and measuring the corresponding deflections to obtain load-deflection curves. Dynamic characterization was performed using modal testing to experimentally determine the first six mode shapes, frequencies, and modal damping values. Static and dynamic characteristics were also determined for a reference truss that served as a characterization baseline. Load-deflection curves and experimental frequency response functions are presented for the reference truss and the articulated-truss joint mounted in the test-bed. The static and dynamic experimental results are compared with analytical predictions obtained from finite element analyses. Load-deflection response is also presented for one of the linear actuators used in the articulated-truss joint. Finally, an assessment is presented for the predictability of the truss hardware used in the reference truss and articulated-truss joint based upon hardware stiffness properties that were previously obtained during the Precision Segmented Reflector (PSR) Technology Development Program.

Characterizing the Fundamental Intellectual Steps Required in the Solution of Conceptual Problems

NASA Astrophysics Data System (ADS)

Stewart, John

2010-02-01

At some level, the performance of a science class must depend on what is taught, the information content of the materials and assignments of the course. The introductory calculus-based electricity and magnetism class at the University of Arkansas is examined using a catalog of the basic reasoning steps involved in the solution of problems assigned in the class. This catalog was developed by sampling popular physics textbooks for conceptual problems. The solution to each conceptual problem was decomposed into its fundamental reasoning steps. These fundamental steps are, then, used to quantify the distribution of conceptual content within the course. Using this characterization technique, an exceptionally detailed picture of the information flow and structure of the class can be produced. The intellectual structure of published conceptual inventories is compared with the information presented in the class and the dependence of conceptual performance on the details of coverage extracted. )

Design and Structure-Function Characterization of 3D Printed Synthetic Porous Biomaterials for Tissue Engineering.

PubMed

Kelly, Cambre N; Miller, Andrew T; Hollister, Scott J; Guldberg, Robert E; Gall, Ken

2018-04-01

3D printing is now adopted for use in a variety of industries and functions. In biomedical engineering, 3D printing has prevailed over more traditional manufacturing methods in tissue engineering due to its high degree of control over both macro- and microarchitecture of porous tissue scaffolds. However, with the improved flexibility in design come new challenges in characterizing the structure-function relationships between various architectures and both mechanical and biological properties in an assortment of clinical applications. Presently, the field of tissue engineering lacks a comprehensive body of literature that is capable of drawing meaningful relationships between the designed structure and resulting function of 3D printed porous biomaterial scaffolds. This work first discusses the role of design on 3D printed porous scaffold function and then reviews characterization of these structure-function relationships for 3D printed synthetic metallic, polymeric, and ceramic biomaterials. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

View northwest, wharf, A portion AA, detail showing timber groin ...

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

View northwest, wharf, A portion AA, detail showing timber groin - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Biochemical and structural characterization of recombinant short-chain NAD(H)-dependent dehydrogenase/reductase from Sulfolobus acidocaldarius highly enantioselective on diaryl diketone benzil.

PubMed

Pennacchio, Angela; Sannino, Vincenzo; Sorrentino, Giosuè; Rossi, Mosè; Raia, Carlo A; Esposito, Luciana

2013-05-01

The gene encoding a novel alcohol dehydrogenase that belongs to the short-chain dehydrogenases/reductases superfamily was identified in the aerobic thermoacidophilic crenarchaeon Sulfolobus acidocaldarius strain DSM 639. The saadh2 gene was heterologously overexpressed in Escherichia coli, and the resulting protein (SaADH2) was purified to homogeneity and both biochemically and structurally characterized. The crystal structure of the SaADH2 NADH-bound form reveals that the enzyme is a tetramer consisting of identical 27,024-Da subunits, each composed of 255 amino acids. The enzyme has remarkable thermophilicity and thermal stability, displaying activity at temperatures up to 80 °C and a 30-min half-inactivation temperature of ∼88 °C. It also shows good tolerance to common organic solvents and a strict requirement for NAD(H) as the coenzyme. SaADH2 displays a preference for the reduction of alicyclic, bicyclic and aromatic ketones and α-ketoesters, but is poorly active on aliphatic, cyclic and aromatic alcohols, showing no activity on aldehydes. Interestingly, the enzyme catalyses the asymmetric reduction of benzil to (R)-benzoin with both excellent conversion (98 %) and optical purity (98 %) by way of an efficient in situ NADH-recycling system involving a second thermophilic ADH. The crystal structure of the binary complex SaADH2-NADH, determined at 1.75 Å resolution, reveals details of the active site providing hints on the structural basis of the enzyme enantioselectivity.

Thermal Analysis by Structural Characterization as a Method for Assessing Heterogeneity in Complex Solid Pharmaceutical Dosage Forms.

PubMed

Alhijjaj, Muqdad; Reading, Mike; Belton, Peter; Qi, Sheng

2015-11-03

Characterizing inter- and intrasample heterogeneity of solid and semisolid pharmaceutical products is important both for rational design of dosage forms and subsequent quality control during manufacture; however, most pharmaceutical products are multicomponent formulations that are challenging in this regard. Thermal analysis, in particular differential scanning calorimetry, is commonly used to obtain structural information, such as degree of crystallinity, or identify the presence of a particular polymorph, but the results are an average over the whole sample; it cannot directly provide information about the spatial distribution of phases. This study demonstrates the use of a new thermo-optical technique, thermal analysis by structural characterization (TASC), that can provide spatially resolved information on thermal transitions by applying a novel algorithm to images acquired by hot stage microscopy. We determined that TASC can be a low cost, relatively rapid method of characterizing heterogeneity and other aspects of structure. In the examples studied, it was found that high heating rates enabled screening times of 3-5 min per sample. In addition, this study demonstrated the higher sensitivity of TASC for detecting the metastable form of polyethylene glycol (PEG) compared to conventional differential scanning calorimetry (DSC). This preliminary work suggests that TASC will be a worthwhile additional tool for characterizing a broad range of materials.

Characterizing the Atomic Structure in Low Concentrations of Weakly Ordered, Weakly Scattering Materials Using the Pair Distribution Function

NASA Astrophysics Data System (ADS)

Terban, Maxwell W.

Nanoscale structural characterization is critical to understanding the physical underpinnings of properties and behavior in materials with technological applications. The work herein shows how the pair distribution function technique can be applied to x-ray total scattering data for material systems which weakly scatter x-rays, a typically difficult task due to the poor signal-to-noise obtained from the structures of interest. Characterization and structural modeling are demonstrated for a variety of molecular and porous systems, along with the detection and characterization of disordered, minority phases and components. In particular, reliable detection and quantitative analysis are demonstrated for nanocrystals of an active pharmaceutical ingredient suspended in dilute solution down to a concentration of 0.25 wt. %, giving a practical limit of detection for ordered nanoscale phases within a disordered matrix. Further work shows that minority nanocrystalline phases can be detected, fingerprinted, and modeled for mixed crystalline and amorphous systems of small molecules and polymers. The crystallization of amorphous lactose is followed under accelerated aging conditions. Melt quenching is shown to produce a different local structure than spray drying or freeze drying, along with increased resistance to crystallization. The initial phases which form in the spray dried formulation are identified as a mixture of polymorphs different from the final alpha-lactose monohydrate form. Hard domain formation in thermoplastic polyurethanes is also characterized as a function of methylene diphenyl diisocyanate and butanediol component ratio, showing that distinct and different hard phase structures can form and are solved by indexing with structures derived from molecular dynamics relaxation. In both cases, phase fractions can be quantified in the mixed crystalline and amorphous systems by fitting with both standards or structure models. Later chapters, demonstrate pair

Detail and gestalt focus in individuals with optimal outcomes from autism spectrum disorders.

PubMed

Fitch, Allison; Fein, Deborah A; Eigsti, Inge-Marie

2015-06-01

Individuals with high-functioning autism (HFA) have a cognitive style that privileges local over global or gestalt details. While not a core symptom of autism, individuals with HFA seem to reliably show this bias. Our lab has been studying a sample of children who have overcome their early ASD diagnoses, showing "optimal outcomes" (OO). This study characterizes performance by OO, HFA, and typically developing (TD) adolescents as they describe paintings under cognitive load. Analyses of detail focus in painting descriptions indicated that the HFA group displayed significantly more local focus than both OO and TD groups, while the OO and TD groups did not differ. We discuss implications for the centrality of detail focus to the autism diagnosis.

Structural Element Testing in Support of the Design of the NASA Composite Crew Module

NASA Technical Reports Server (NTRS)

Kellas, Sotiris; Jackson, Wade C.; Thesken, John C.; Schleicher, Eric; Wagner, Perry; Kirsch, Michael T.

2012-01-01

In January 2007, the NASA Administrator and Associate Administrator for the Exploration Systems Mission Directorate chartered the NASA Engineering and Safety Center (NESC) to design, build, and test a full-scale Composite Crew Module (CCM). For the design and manufacturing of the CCM, the team adopted the building block approach where design and manufacturing risks were mitigated through manufacturing trials and structural testing at various levels of complexity. Following NASA's Structural Design Verification Requirements, a further objective was the verification of design analysis methods and the provision of design data for critical structural features. Test articles increasing in complexity from basic material characterization coupons through structural feature elements and large structural components, to full-scale structures were evaluated. This paper discusses only four elements tests three of which include joints and one that includes a tapering honeycomb core detail. For each test series included are specimen details, instrumentation, test results, a brief analysis description, test analysis correlation and conclusions.

Atomic and Molecular Beam Scattering: Characterizing Structure and Dynamics of Hybrid Organic-Semiconductor Interfaces and Introducing Novel Isotope Separation Techniques

NASA Astrophysics Data System (ADS)

Nihill, Kevin John

This thesis details a range of experiments and techniques that use the scattering of atomic beams from surfaces to both characterize a variety of interfaces and harness mass-specific scattering conditions to separate and enrich isotopic components in a mixture of gases. Helium atom scattering has been used to characterize the surface structure and vibrational dynamics of methyl-terminated Ge(111), thereby elucidating the effects of organic termination on a rigid semiconductor interface. Helium atom scattering was employed as a surface-sensitive, non-destructive probe of the surface. By means of elastic gas-surface diffraction, this technique is capable of providing measurements of atomic spacing, step height, average atomic displacement as a function of surface temperature, gas-surface potential well depth, and surface Debye temperature. Inelastic time-of-flight studies provide highly resolved energy exchange measurements between helium atoms and collective lattice vibrations, or phonons; a collection of these measurements across a range of incident kinematic parameters allowed for a thorough mapping of low-energy phonons (e.g., the Rayleigh wave) across the surface Brillouin zone and subsequent comparison with complementary theoretical calculations. The scattering of molecular beams - here, hydrogen and deuterium from methyl-terminated Si(111) - enables the measurement of the anisotropy of the gas-surface interaction potential through rotationally inelastic diffraction (RID), whereby incident atoms can exchange internal energy between translational and rotational modes and diffract into unique angular channels as a result. The probability of rotational excitations as a function of incident energy and angle were measured and compared with electronic structure and scattering calculations to provide insight into the gas-surface interaction potential and hence the surface charge density distribution, revealing important details regarding the interaction of H2 with an

The Essential Role of Tethered Balloons in Characterizing Boundary Layer Structure and Evolution during Discover-AQ

NASA Astrophysics Data System (ADS)

Clark, R. D.

2014-12-01

The NASA DISCOVER-AQ (Deriving Information on Surface conditions from Column and Vertically Resolved Observations Relevant to Air Quality) provided the opportunity to observe the influence of local and regional circulations on the structure and evolution of the boundary layer (BL) and in turn study the associated effects on air quality and aerosol trends within four different airsheds. An extended network of ground-based instruments, balloon-borne profilers, and remote sensing instruments supported the in-situ airborne measurements made by the NASA aircraft in capturing the structure and evolution of the daytime BL. The Millersville University Atmospheric Research and Aerostat Facility (MARAF) is one of many assets deployed for DISCOVER-AQ. Central to MARAF is a heavy-lift-capacity tethered balloon (aerostat) used to obtain high resolution profiles of meteorological variables, trace gases, and particulates in the BL. The benefit of including a tethered balloon is that it can fill a data void between the surface and the lowest altitudes flown by the aircraft and provide critical time-height series for ground-based remote sensing instruments in the layer below their first range gate. MARAF also includes an acoustic sodar with RASS, MPL4 micropulse Lidar, 4-meter flux tower, rawinsonde system, and a suite of trace gas analyzers (O3, NOx/NO2/NO, CO, and SO2), 3-wavelength nephelometer, and particle sizers/counters spanning the range from 10 nm to 10 microns. MARAF is capable of providing a detailed and nearly continuous Eulerian characterization of the surface layer and lower BL, and with proper FAA airspace authorization, can be deployed both day and night. Three case studies will be presented that incorporate the MARAF into the combined assets of DISCOVER-AQ to better characterize: 1) bay breeze convergence, recirculation, and ramp-up events in Edgewood, MD in July 2011; 2) aerosol transport over Central Valley, CA in January 2013; and 3) multiple sea-bay breeze

Structural characterization of Papilio kotzebuea (Eschscholtz 1821) butterfly wings

NASA Astrophysics Data System (ADS)

Sackey, J.; Nuru, Z. Y.; Berthier, S.; Maaza, M.

2018-05-01

The `plain black' forewings and black with `red spot' hindwings of the Papilio kotzebuea (Eschscholtz, 1821) were characterized by Scanning Electron Microscopy (SEM), Energy-Dispersive x-ray Spectroscopy (EDS), Atomic Force Microscopy (AFM), Fourier transform Infrared spectroscopy (FT-IR), UV-Vis spectrophometer and NIRQuest spectrometer. SEM images showed that the two sections of wings have different structures. The black with `red spot' hindwings have `hair-like' structures attached to the ridges and connected to the lamellae. On the contrary, the `plain black' forewings have holes that separate the ridges. AFM analysis unveiled that the `plain black' forewings have higher average surfaces roughness values as compared with the black with `red spot' hindwing. EDS and FT-IR results confirmed the presence of naturally hydrophobic materials on the wings. The `plain black' forewing exhibited strong absorptance (97%) throughout the solar spectrum range, which is attributed to the high melanin concentration as well as to the presence of holes in the scales. Biomimicking this wing could serves as equivalent solar absorber material.

Structural characterization of agonist and antagonist-bound acetylcholine-binding protein from Aplysia californica.

PubMed

Hansen, Scott B; Sulzenbacher, Gerlind; Huxford, Tom; Marchot, Pascale; Bourne, Yves; Taylor, Palmer

2006-01-01

Nicotinic acetylcholine receptors (nAChRs) are well-characterized allosteric transmembrane proteins involved in the rapid gating of ions elicited by ACh. These receptors belong to the Cys-loop superfamily of ligand-gated ion channels, which also includes GABAA and GABAC, 5-HT3, and glycine receptors. The nAChRs are homo- or heteromeric pentamers of structurally related subunits that encompass an extracellular N-terminal ligand-binding domain, four transmembrane-spanning regions that form the ion channel, and an extended intracellular region between spans 3 and 4. Ligand binding triggers conformational changes that are transmitted to the transmembrane-spanning region, leading to gating and changes in membrane potential. The four transmembrane spans on each of the five subunits create a substantial region of hydrophobicity that precludes facile crystallization of this protein. However the freshwater snail, Lymnaea stagnalis, produces a soluble homopentameric protein, termed the ACh-binding protein (AChBP), which binds ACh (Smit et al., 2001). Its structure was determined recently (Brejc et al., 2001) at high resolution, revealing the structural scaffold for nAChR, and has become a functional and structural surrogate of the nAChR ligand-binding domain. We have characterized an AChBP from Aplysia californica and determined distinct ligand-binding properties when compared to those of L. stagnalis, including ligand specificity for the nAChR alpha7 subtype-specific alpha-conotoxin ImI (Hansen et al., 2004).

Structural and physicochemical characterization of thermoplastic corn starch films containing microalgae.

PubMed

Fabra, María José; Martínez-Sanz, Marta; Gómez-Mascaraque, L G; Gavara, Rafael; López-Rubio, Amparo

2018-04-15

This work provides an in-depth analysis on how the addition of different microalgae species (Nannochloropsis, Spirulina and Scenedesmus) affected the structural and physicochemical properties of thermoplastic corn starch biocomposites. Structural characterization was conducted by combined SAXS/WAXS experiments and it was correlated with mechanical and barrier properties of the biocomposites. A water vapour permeability drop of ca. 54% was observed upon addition of the different microalgae species. The oxygen permeability and the mechanical properties of biocomposites containing Spirulina or Scenedesmus were not improved since the presence of microalgae hindered the re-arrangement and packing of the lamellar structure of starch polymeric chains, according to the SAXS results. Nannochloropsis caused a great reduction of the matrix rigidity and, the oxygen permeability was also improved. Therefore, all of these features make the Nannochloropsis biocomposites an alternative to generate biodegradable food packaging materials with the additional advantage that they can be easily scaled-up. Copyright © 2018 Elsevier Ltd. All rights reserved.

Inflight Characterization of the Cassini Spacecraft Propellant Slosh and Structural Frequencies

NASA Technical Reports Server (NTRS)

Lee, Allan Y.; Stupik, Joan

2015-01-01

While there has been extensive theoretical and analytical research regarding the characterization of spacecraft propellant slosh and structural frequencies, there have been limited studies to compare the analytical predictions with measured flight data. This paper uses flight telemetry from the Cassini spacecraft to get estimates of high-g propellant slosh frequencies and the magnetometer boom frequency characteristics, and compares these values with those predicted by theoretical works. Most Cassini attitude control data are available at a telemetry frequency of 0.5 Hz. Moreover, liquid sloshing is attenuated by propellant management device and attitude controllers. Identification of slosh and structural frequency are made on a best-effort basis. This paper reviews the analytical approaches that were used to predict the Cassini propellant slosh frequencies. The predicted frequencies are then compared with those estimated using telemetry from selected Cassini burns where propellant sloshing was observed (such as the Saturn Orbit Insertion burn). Determination of the magnetometer boom structural frequency is also discussed.

Characterization of Structural and Pigmentary Colors in Common Emigrant (Catopsilia Pomona) Butterfly

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

Ghate, Ekata; Kulkarni, G. R.; Bhoraskar, S. V.

2011-10-20

Study of structural colors in case of insects and butterflies is important for their biomimic and biophotonics applications. Structural color is the color which is produced by physical structures and their interaction with light while pigmentary color is produced by absorption of light by pigments. Common Emigrant butterfly is widely distributed in India. It is of moderate size with wing span of about 60-80 mm. The wings are broadly white with yellow or sulphur yellow coloration at places as well as few dark black patches. It belongs to family Pieridae. A study of structural color in case of Common Emigrantmore » butterfly has been carried out in the present work. The characterization of wing color was performed using absorption spectroscopy. Scanning electron microscopic study of the wings of Common Emigrant butterfly showed that three different types of scales are present on the wing surface dorsally. Diffracting structures are present in certain parts of the surfaces of the various scales. Bead like structures are embedded in the intricate structures of the scales. Absorption spectra revealed that a strong absorption peak is seen in the UV-range. Crystalline structure of beads was confirmed by the X-ray diffraction analysis.« less

Two worlds collide: Image analysis methods for quantifying structural variation in cluster molecular dynamics

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

Steenbergen, K. G., E-mail: kgsteen@gmail.com; Gaston, N.

2014-02-14

Inspired by methods of remote sensing image analysis, we analyze structural variation in cluster molecular dynamics (MD) simulations through a unique application of the principal component analysis (PCA) and Pearson Correlation Coefficient (PCC). The PCA analysis characterizes the geometric shape of the cluster structure at each time step, yielding a detailed and quantitative measure of structural stability and variation at finite temperature. Our PCC analysis captures bond structure variation in MD, which can be used to both supplement the PCA analysis as well as compare bond patterns between different cluster sizes. Relying only on atomic position data, without requirement formore » a priori structural input, PCA and PCC can be used to analyze both classical and ab initio MD simulations for any cluster composition or electronic configuration. Taken together, these statistical tools represent powerful new techniques for quantitative structural characterization and isomer identification in cluster MD.« less

Two worlds collide: image analysis methods for quantifying structural variation in cluster molecular dynamics.

PubMed

Steenbergen, K G; Gaston, N

2014-02-14

Inspired by methods of remote sensing image analysis, we analyze structural variation in cluster molecular dynamics (MD) simulations through a unique application of the principal component analysis (PCA) and Pearson Correlation Coefficient (PCC). The PCA analysis characterizes the geometric shape of the cluster structure at each time step, yielding a detailed and quantitative measure of structural stability and variation at finite temperature. Our PCC analysis captures bond structure variation in MD, which can be used to both supplement the PCA analysis as well as compare bond patterns between different cluster sizes. Relying only on atomic position data, without requirement for a priori structural input, PCA and PCC can be used to analyze both classical and ab initio MD simulations for any cluster composition or electronic configuration. Taken together, these statistical tools represent powerful new techniques for quantitative structural characterization and isomer identification in cluster MD.

4. DETAIL OF SOUTH (FRONT) ELEVATION AT EAST END OF ...

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

4. DETAIL OF SOUTH (FRONT) ELEVATION AT EAST END OF PORCH WITH STRUCTURAL SYSTEM OF WOOD FRAME WITH BRICK NOGGING REVEALED. - Andalusia, The Cottage, State Road vicinity (Bensalem Township), Andalusia, Bucks County, PA

Synthesis, spectral characterization and structural studies of a novel O, N, O donor semicarbazone and its binuclear copper complex with hydrogen bond stabilized lattice

NASA Astrophysics Data System (ADS)

Layana, S. R.; Saritha, S. R.; Anitha, L.; Sithambaresan, M.; Sudarsanakumar, M. R.; Suma, S.

2018-04-01

A novel O,N,O donor salicylaldehyde-N4-phenylsemicarbazone, (H2L) has been synthesized and physicochemically characterized. Detailed structural studies of H2L using single crystal X-ray diffraction technique reveals the existence of intra and inter molecular hydrogen bonding interactions, which provide extra stability to the molecule. We have successfully synthesized a binuclear copper(II) complex, [Cu2(HL)2(NO3)(H2O)2]NO3 with phenoxy bridging between the two copper centers. The complex was characterized by elemental analysis, magnetic susceptibility and conductivity measurements, FT-IR, UV-Visible, mass and EPR spectral methods. The grown crystals of the copper complex were employed for the single crystal X-ray diffraction studies. The complex possesses geometrically different metal centers, in which the ligand coordinates through ketoamide oxygen, azomethine nitrogen and deprotonated phenoxy oxygen. The extensive intermolecular hydrogen bonding interactions of the coordinated and the lattice nitrate groups interconnect the complex units to form a 2D supramolecular assembly. The ESI mass spectrum substantiates the existence of 1:1 complex. The g values obtained from the EPR spectrum in frozen DMF suggest dx2 -y2 ground state for the unpaired electron.

Advanced structural analysis of nanoporous materials by thermal response measurements.

PubMed

Oschatz, Martin; Leistner, Matthias; Nickel, Winfried; Kaskel, Stefan

2015-04-07

Thermal response measurements based on optical adsorption calorimetry are presented as a versatile tool for the time-saving and profound characterization of the pore structure of porous carbon-based materials. This technique measures the time-resolved temperature change of an adsorbent during adsorption of a test gas. Six carbide and carbon materials with well-defined nanopore architecture including micro- and/or mesopores are characterized by thermal response measurements based on n-butane and carbon dioxide as the test gases. With this tool, the pore systems of the model materials can be clearly distinguished and accurately analyzed. The obtained calorimetric data are correlated with the adsorption/desorption isotherms of the materials. The pore structures can be estimated from a single experiment due to different adsorption enthalpies/temperature increases in micro- and mesopores. Adsorption/desorption cycling of n-butane at 298 K/1 bar with increasing desorption time allows to determine the pore structure of the materials in more detail due to different equilibration times. Adsorption of the organic test gas at selected relative pressures reveals specific contributions of particular pore systems to the increase of the temperature of the samples and different adsorption mechanisms. The use of carbon dioxide as the test gas at 298 K/1 bar provides detailed insights into the ultramicropore structure of the materials because under these conditions the adsorption of this test gas is very sensitive to the presence of pores smaller than 0.7 nm.

Advanced electron microscopy characterization of tri-layer rare-earth oxide superlattices

NASA Astrophysics Data System (ADS)

Phillips, Patrick; Disa, Ankit; Ismail-Beigi, Sohrab; Klie, Robert; University of Illinois-Chicago Team; Yale University Team

2015-03-01

Rare-earth nickelates are known to display complex electronic and magnetic behaviors owed to a very localized and sensitive Ni-site atomic and electronic structure. Toward realizing the goal of manipulating of the energetic ordering of Ni d orbitals and 2D conduction, the present work focuses on the experimental characterization of thin film superlattice structures consisting of alternating layers of LaTiO3 and LaNiO3 sandwiched between a dull insulator, LaAlO3. Using advanced scanning transmission electron microscopy (STEM)-based methods, properties such as interfacial sharpness, electron transfer, O presence, and local electronic structure can be probed at the atomic scale, and will be discussed at length. By combining both energy dispersive X-ray (EDX) and electronic energy loss (EEL) spectroscopies in an aberration-corrected STEM, it is possible to attain energy and spatial resolutions of 0.35 eV and 100 pm, respectively. Focus of the talk will remain not only on the aforementioned properties, but will also include details and parameters of the acquisitions to facilitate future characterization at this level.

Detailed transient heme structures of Mb-CO in solution after CO dissociation: an X-ray transient absorption spectroscopic study.

PubMed

Stickrath, Andrew B; Mara, Michael W; Lockard, Jenny V; Harpham, Michael R; Huang, Jier; Zhang, Xiaoyi; Attenkofer, Klaus; Chen, Lin X

2013-04-25

Although understanding the structural dynamics associated with ligand photodissociation is necessary in order to correlate structure and function in biological systems, few techniques are capable of measuring the ultrafast dynamics of these systems in solution-phase at room temperature. We present here a detailed X-ray transient absorption (XTA) study of the photodissociation of CO-bound myoglobin (Fe(II)CO-Mb) in room-temperature aqueous buffer solution with a time resolution of 80 ps, along with a general procedure for handling biological samples under the harsh experimental conditions that transient X-ray experiments entail. The XTA spectra of (Fe(II)CO-Mb) exhibit significant XANES and XAFS alterations following 527 nm excitation, which remain unchanged for >47 μs. These spectral changes indicate loss of the CO ligand, resulting in a five-coordinate, domed heme, and significant energetic reorganization of the 3d orbitals of the Fe center. With the current experimental setup, each X-ray pulse in the pulse train, separated by ~153 ns, can be separately discriminated, yielding snapshots of the myoglobin evolution over time. These methods can be easily applied to other biological systems, allowing for simultaneous structural and electronic measurements of any biological system with both ultrafast and slow time resolutions, effectively mapping out all of the samples' relevant physiological processes.

Structural Characterization of a Thrombin-Aptamer Complex by High Resolution Native Top-Down Mass Spectrometry

NASA Astrophysics Data System (ADS)

Zhang, Jiang; Loo, Rachel R. Ogorzalek; Loo, Joseph A.

2017-09-01

Native mass spectrometry (MS) with electrospray ionization (ESI) has evolved as an invaluable tool for the characterization of intact native proteins and non-covalently bound protein complexes. Here we report the structural characterization by high resolution native top-down MS of human thrombin and its complex with the Bock thrombin binding aptamer (TBA), a 15-nucleotide DNA with high specificity and affinity for thrombin. Accurate mass measurements revealed that the predominant form of native human α-thrombin contains a glycosylation mass of 2205 Da, corresponding to a sialylated symmetric biantennary oligosaccharide structure without fucosylation. Native MS showed that thrombin and TBA predominantly form a 1:1 complex under near physiological conditions (pH 6.8, 200 mM NH4OAc), but the binding stoichiometry is influenced by the solution ionic strength. In 20 mM ammonium acetate solution, up to two TBAs were bound to thrombin, whereas increasing the solution ionic strength destabilized the thrombin-TBA complex and 1 M NH4OAc nearly completely dissociated the complex. This observation is consistent with the mediation of thrombin-aptamer binding through electrostatic interactions and it is further consistent with the human thrombin structure that contains two anion binding sites on the surface. Electron capture dissociation (ECD) top-down MS of the thrombin-TBA complex performed with a high resolution 15 Tesla Fourier transform ion cyclotron resonance (FTICR) mass spectrometer showed the primary binding site to be at exosite I located near the N-terminal sequence of the heavy chain, consistent with crystallographic data. High resolution native top-down MS is complementary to traditional structural biology methods for structurally characterizing native proteins and protein-DNA complexes. [Figure not available: see fulltext.

Structural and Mechanistic Insights into C-P Bond Hydrolysis by Phosphonoacetate Hydrolase

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

Agarwal, Vinayak; Borisova, Svetlana A.; Metcalf, William W.

2011-12-22

Bacteria have evolved pathways to metabolize phosphonates as a nutrient source for phosphorus. In Sinorhizobium meliloti 1021, 2-aminoethylphosphonate is catabolized to phosphonoacetate, which is converted to acetate and inorganic phosphate by phosphonoacetate hydrolase (PhnA). Here we present detailed biochemical and structural characterization of PhnA that provides insights into the mechanism of C-P bond cleavage. The 1.35 {angstrom} resolution crystal structure reveals a catalytic core similar to those of alkaline phosphatases and nucleotide pyrophosphatases but with notable differences, such as a longer metal-metal distance. Detailed structure-guided analysis of active site residues and four additional cocrystal structures with phosphonoacetate substrate, acetate, phosphonoformatemore » inhibitor, and a covalently bound transition state mimic provide insight into active site features that may facilitate cleavage of the C-P bond. These studies expand upon the array of reactions that can be catalyzed by enzymes of the alkaline phosphatase superfamily.« less

Analysis of sulfates on low molecular weight heparin using mass spectrometry: structural characterization of enoxaparin.

PubMed

Gupta, Rohitesh; Ponnusamy, Moorthy P

2018-05-31

Structural characterization of low molecular weight heparin (LMWH) is critical to meet biosimilarity standards. In this context, the review focuses on structural analysis of labile sulfates attached to the side-groups of LMWH using mass spectrometry. A comprehensive review of this topic will help readers to identify key strategies for tackling the problem related to sulfate loss. At the same time, various mass spectrometry techniques are presented to facilitate compositional analysis of LMWH, mainly enoxaparin. Areas covered: This review summarizes findings on mass spectrometry application for LMWH, including modulation of sulfates, using enzymology and sample preparation approaches. Furthermore, popular open-source software packages for automated spectral data interpretation are also discussed. Successful use of LC/MS can decipher structural composition for LMWH and help evaluate their sameness or biosimilarity with the innovator molecule. Overall, the literature has been searched using PubMed by typing various search queries such as 'enoxaparin', 'mass spectrometry', 'low molecular weight heparin', 'structural characterization', etc. Expert commentary: This section highlights clinically relevant areas that need improvement to achieve satisfactory commercialization of LMWHs. It also primarily emphasizes the advancements in instrumentation related to mass spectrometry, and discusses building automated software for data interpretation and analysis.

Hierarchical structure observation and nanoindentation size effect characterization for a limnetic shell

NASA Astrophysics Data System (ADS)

Song, Jingru; Fan, Cuncai; Ma, Hansong; Wei, Yueguang

2015-06-01

In the present research, hierarchical structure observation and mechanical property characterization for a type of biomaterial are carried out. The investigated biomaterial is Hyriopsis cumingii, a typical limnetic shell, which consists of two different structural layers, a prismatic "pillar" structure and a nacreous "brick and mortar" structure. The prismatic layer looks like a "pillar forest" with variation-section pillars sized on the order of several tens of microns. The nacreous material looks like a "brick wall" with bricks sized on the order of several microns. Both pillars and bricks are composed of nanoparticles. The mechanical properties of the hierarchical biomaterial are measured by using the nanoindentation test. Hardness and modulus are measured for both the nacre layer and the prismatic layer, respectively. The nanoindentation size effects for the hierarchical structural materials are investigated experimentally. The results show that the prismatic nanostructured material has a higher stiffness and hardness than the nacre nanostructured material. In addition, the nanoindentation size effects for the hierarchical structural materials are described theoretically, by using the trans-scale mechanics theory considering both strain gradient effect and the surface/interface effect. The modeling results are consistent with experimental ones.

Norharmane rhenium(I) polypyridyl complexes: synthesis, structural and spectroscopic characterization.

PubMed

Maisuls, Iván; Wolcan, Ezequiel; Piro, Oscar E; Etcheverría, Gustavo A; Petroselli, Gabriela; Erra-Ballsels, Rosa; Cabrerizo, Franco M; Ruiz, Gustavo T

2015-10-21

Two novel Re(i) complexes with the general formula fac-[Re(CO)3(L)(nHo)]CF3SO3, where L = 2,2'-bipyridine (bpy) or 1,10 phenanthroline (phen) and nHo (9H-pyrido[3,4-b]indole; norharmane) have been synthesized. The Re(i)-nHo complexes were characterized by structural X-ray diffraction, (1)H and (13)C NMR, UV-vis absorption and FT-IR spectroscopy, and by a combination of two mass spectrometry techniques, namely ESI-MS and UV-MALDI-MS. All characterizations showed that nHo is coordinated to the metal atom by the pyridine nitrogen of the molecule. X-ray structural analysis revealed that the crystal lattices for both complexes are further stabilized by a strong >N-HO bond between the pyrrole NH group of the pyridoindole ligand and one oxygen atom of the trifluoromethanesulfonate counter-ion. Ground state geometry optimization by DFT calculations showed that in fluid solution the nHo ligand may rotate freely. The nature of the electronic transitions of Re(CO)3(bpy)(nHo)(+) were established by TD-DFT calculations. The set of the most important electronic transitions present in this complex are comprised of π→π* electronic transitions centered on bpy and nHo moieties, LLCTnHo→COs, MLLCTRe(CO)3→bpy and LLCTnHo→bpy transitions. Additionally, TD-DFT calculations predict the existence of another two intense MLLCTRe(CO)3→nHo electronic transitions. Calculated UV-vis absorption spectra are in good agreement with the corresponding experimental data for the bpy-containing complex.

Biological and Structural Characterization of Rotamers of C-C Chemokine Receptor Type 5 (CCR5) Inhibitor GSK214096.

PubMed

Kazmierski, Wieslaw M; Danehower, Susan; Duan, Maosheng; Ferris, Robert G; Elitzin, Vassil; Minick, Douglas; Sharp, Matthew; Stewart, Eugene; Villeneuve, Manon

2014-12-11

We recently reported the discovery of preclinical CCR5 inhibitor GSK214096, 1 (J. Med. Chem. 2011, 54, 756). Detailed characterization of 1 revealed that it exists as a mixture of four separable atropisomers A-D. The two slow-interconverting pairs of rotamers A + B and C + D were separated and further characterized. HIV and CCR5-mediated chemotaxis data strongly suggest that the antiviral potency of 1 is due to rotamers A + B and not C + D. Furthermore, integrated UV, vibrational circular dichroism VCD and computational approach allowed to determine the M chirality in C + D (and P chirality in A + B). These findings imply additional avenues to be pursued toward new CCR5 antagonists.

Detailed petrophysical characterization enhances geological mapping of a buried substratum using aeromagnetic and gravity data; application to the southwestern Paris basin

NASA Astrophysics Data System (ADS)

Baptiste, Julien; Martelet, Guillaume; Faure, Michel; Beccaletto, Laurent; Chen, Yan; Reninger, Pierre-Alexandre

2016-04-01

Mapping the geometries (structure and lithology) of a buried basement is a key for targeting resources and for improving the regional geological knowledge. The Paris basin is a Mesozoic to Cenozoic intraplate basin set up on a Variscan substratum, which crops out in the surrounding massifs. We focus our study on the southwestern part of the Paris basin at its junction with the Aquitaine basin. This Mezo-Cenozoic cover separates the Armorican Massif and the Massif Central which compose of several litho-tectonic units bounded by crustal-scale shear zones. In spite of several lithological and structural correlations between various domains of the two massifs, their geological connection, hidden below the Paris basin sedimentary cover, is still largely debated. Potential field geophysics have proven effective for mapping buried basin/basement interfaces. In order to enhance the cartographic interpretation of these data, we have set up a detailed petrophysical library (field magnetic susceptibility data and density measurements on rock samples) of the Paleozoic rocks outcropping in the Variscan massifs. The combination of aeromagnetic and gravity data supported by the petrophysical signatures and field/borehole geological information, is carried out to propose a new map of the architecture of the Variscan substratum. The new synthetic map of geophysical signature of the Paris basin basement combines: i) the magnetic anomaly reduced to the pole, ii) the vertical gradient of the Bouguer anomaly and iii) the tilt derivative of the magnetic anomaly reduced to the pole. Based on this information, the Eastern extension of the major shear zones below the sedimentary cover is assessed. The petrophysical signatures were classified in three classes of magnetic susceptibility and density: low, intermediate and high. Basic rocks have high magnetization and density values whereas granite, migmatite and orthogneiss show low magnetization and density values, Proterozoic and Paleozoic

Nondestructive evaluation/characterization of composite materials and structures using the acousto-ultrasonic techniques

NASA Technical Reports Server (NTRS)

Dos Reis, H. L. M.; Vary, A.

1988-01-01

This paper introduces the nature and the underlying rational of the acousto-ultrasonic stress wave factor technique and some of its applications to composite materials and structures. Furthermore, two examples of successful application of the acousto-ultrasonic technique are presented in detail. In the first example, the acousto-ultrasonic technique is used to evaluate the adhesive bond strength between rubber layers and steel plates, and in the seocnd example the tehcnique is used to monitor progressive damage in wire rope.

Structural and Electrochemical Characterization of Zn1-xFexO-Effect of Aliovalent Doping on the Li⁺ Storage Mechanism.

PubMed

Giuli, Gabriele; Eisenmann, Tobias; Bresser, Dominic; Trapananti, Angela; Asenbauer, Jakob; Mueller, Franziska; Passerini, Stefano

2017-12-29

In order to further improve the energy and power density of state-of-the-art lithium-ion batteries (LIBs), new cell chemistries and, therefore, new active materials with alternative storage mechanisms are needed. Herein, we report on the structural and electrochemical characterization of Fe-doped ZnO samples with varying dopant concentrations, potentially serving as anode for LIBs (Rechargeable lithium-ion batteries). The wurtzite structure of the Zn 1-x Fe x O samples (with x ranging from 0 to 0.12) has been refined via the Rietveld method. Cell parameters change only slightly with the Fe content, whereas the crystallinity is strongly affected, presumably due to the presence of defects induced by the Fe 3+ substitution for Zn 2+ . XANES (X-ray absorption near edge structure) data recorded ex situ for Zn 0.9 Fe 0.1 O electrodes at different states of charge indicated that Fe, dominantly trivalent in the pristine anode, partially reduces to Fe 2+ upon discharge. This finding was supported by a detailed galvanostatic and potentiodynamic investigation of Zn 1-x Fe x O-based electrodes, confirming such an initial reduction of Fe 3+ to Fe 2+ at potentials higher than 1.2 V (vs. Li⁺/Li) upon the initial lithiation, i.e., discharge. Both structural and electrochemical data strongly suggest the presence of cationic vacancies at the tetrahedral sites, induced by the presence of Fe 3+ (i.e., one cationic vacancy for every two Fe 3+ present in the sample), allowing for the initial Li⁺ insertion into the ZnO lattice prior to the subsequent conversion and alloying reaction.

44. Detail, bridge land span outboard girder brackets carrying utility ...

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

44. Detail, bridge land span outboard girder brackets carrying utility conduit. Structure rests on granite blocks mounted on granite piers. - Broadway Bridge, Spanning Foundry Street, MBTA Yard, Fort Point Channel, & Lehigh Street, Boston, Suffolk County, MA

6. DETAIL OF ENTRY ON NORTH ELEVATION OF BUILDING 260 ...

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

6. DETAIL OF ENTRY ON NORTH ELEVATION OF BUILDING 260 (STORAGE STRUCTURE) IN STORAGE AREA. - Loring Air Force Base, Weapons Storage Area, Northeastern corner of base at northern end of Maine Road, Limestone, Aroostook County, ME

Synthesis and structural characterization of betaine- and imidazoline-based organoclays

NASA Astrophysics Data System (ADS)

Lazorenko, Georgy; Kasprzhitskii, Anton; Yavna, Victor

2018-01-01

The samples of organic-modified clays based on a Wyoming SWy-2 sodium montmorillonite (Na+-Mt) with the cationic surfactant hydroxyethylalkyl imidazoline (HEAI) and the amphoteric surfactant oleylamidopropyl betaine (OAPB) were synthesized via a cation exchange process. The obtained materials were characterized using XRD analysis, ATR-FTIR spectroscopy, SEM, BET and Water contact angle measurements. The potential sites of binding of OAPB and HEAI to the mineral surface were determined by the DFT calculations. For the variants of the structure of the complex, DFT calculations is performed and the interaction energy of the surfactant and clay mineral is estimated.

Characterizing Woody Vegetation Spectral and Structural Parameters with a 3-D Scene Model

NASA Astrophysics Data System (ADS)

Qin, W.; Yang, L.

2004-05-01

Quantification of structural and biophysical parameters of woody vegetation is of great significance in understanding vegetation condition, dynamics and functionality. Such information over a landscape scale is crucial for global and regional land cover characterization, global carbon-cycle research, forest resource inventories, and fire fuel estimation. While great efforts and progress have been made in mapping general land cover types over large area, at present, the ability to quantify regional woody vegetation structural and biophysical parameters is limited. One approach to address this research issue is through an integration of physically based 3-D scene model with multiangle and multispectral remote sensing data and in-situ measurements. The first step of this work is to model woody vegetation structure and its radiation regime using a physically based 3-D scene model and field data, before a robust operational algorithm can be developed for retrieval of important woody vegetation structural/biophysical parameters. In this study, we use an advanced 3-D scene model recently developed by Qin and Gerstl (2000), based on L-systems and radiosity theories. This 3-D scene model has been successfully applied to semi-arid shrubland to study structure and radiation regime at a regional scale. We apply this 3-D scene model to a more complicated and heterogeneous forest environment dominated by deciduous and coniferous trees. The data used in this study are from a field campaign conducted by NASA in a portion of the Superior National Forest (SNF) near Ely, Minnesota during the summers of 1983 and 1984, and supplement data collected during our revisit to the same area of SNF in summer of 2003. The model is first validated with reflectance measurements at different scales (ground observations, helicopter, aircraft, and satellite). Then its ability to characterize the structural and spectral parameters of the forest scene is evaluated. Based on the results from this study

Characterization and analysis of Porous, Brittle solid structures by X-ray micro computed tomography

NASA Astrophysics Data System (ADS)

Lin, C. L.; Videla, A. R.; Yu, Q.; Miller, J. D.

2010-12-01

The internal structure of porous, brittle solid structures, such as porous rock, foam metal and wallboard, is extremely complex. For example, in the case of wallboard, the air bubble size and the thickness/composition of the wall structure are spatial parameters that vary significantly and influence mechanical, thermal, and acoustical properties. In this regard, the complex geometry and the internal texture of material, such as wallboard, is characterized and analyzed in 3-D using cone beam x-ray micro computed tomography. Geometrical features of the porous brittle structure are quantitatively analyzed based on calibration of the x-ray linear attenuation coefficient, use of a 3-D watershed algorithm, and use of a 3-D skeletonization procedure. Several examples of the 3-D analysis for porous, wallboard structures are presented and the results discussed.

Characterization and elimination of undesirable protein residues in plant cell walls for enhancing lignin analysis by solution-state 2D gel-NMR methods

USDA-ARS?s Scientific Manuscript database

Proteins exist in every plant cell wall. Certain protein residues interfere with lignin characterization and quantification. The current solution-state 2D-NMR technique (gel-NMR) for whole plant cell wall structural profiling provides detailed information regarding cell walls and proteins. However, ...

Morphology and characterization of 3D micro-porous structured chitosan scaffolds for tissue engineering.

PubMed

Hsieh, Wen-Chuan; Chang, Chih-Pong; Lin, Shang-Ming

2007-06-15

This research studies the morphology and characterization of three-dimensional (3D) micro-porous structures produced from biodegradable chitosan for use as scaffolds for cells culture. The chitosan 3D micro-porous structures were produced by a simple liquid hardening method, which includes the processes of foaming by mechanical stirring without any chemical foaming agent added, and hardening by NaOH cross linking. The pore size and porosity were controlled with mechanical stirring strength. This study includes the morphology of chitosan scaffolds, the characterization of mechanical properties, water absorption properties and in vitro enzymatic degradation of the 3D micro-porous structures. The results show that chitosan 3D micro-porous structures were successfully produced. Better formation samples were obtained when chitosan concentration is at 1-3%, and concentration of NaOH is at 5%. Faster stirring rate would produce samples of smaller pore diameter, but when rotation speed reaches 4000 rpm and higher the changes in pore size is minimal. Water absorption would reduce along with the decrease of chitosan scaffolds' pore diameter. From stress-strain analysis, chitosan scaffolds' mechanical properties are improved when it has smaller pore diameter. From in vitro enzymatic degradation results, it shows that the disintegration rate of chitosan scaffolds would increase along with the processing time increase, but approaching equilibrium when the disintegration rate reaches about 20%.

13. Detail, typical window with fireproof shutters closed, northeast rear, ...

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

13. Detail, typical window with fireproof shutters closed, northeast rear, view to southwest, 135mm lens. Note cracks evidencing structural failure. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

12. Detail, typical window with fireproof shutters open, northeast rear, ...

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

12. Detail, typical window with fireproof shutters open, northeast rear, view to southwest, 135mm lens. Note cracks evidencing structural failure. - Benicia Arsenal, Powder Magazine No. 5, Junction of Interstate Highways 680 & 780, Benicia, Solano County, CA

View northwest, wharf B, timber framing, detail of cross bracing, ...

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

View northwest, wharf B, timber framing, detail of cross bracing, charred piers, recent galvanized fastenings - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Physicochemical characterization of mineral deposits in human ligamenta flava.

PubMed

Orzechowska, Sylwia; Wróbel, Andrzej; Kozieł, Marcin; Łasocha, Wiesław; Rokita, Eugeniusz

2018-05-01

The aim of our study was the detailed characterization of calcium deposits in ligamenta flava. The use of microcomputed tomography allowed extending the routine medical investigations to characterize mineral grains in the microscopic scale. A possible connection between spinal stenosis and ligament mineralization was investigated. The studies were carried out on 24 surgically removed ligamentum flavum samples divided into control and stenosis groups. Physicochemical characterization of the inorganic material was performed using X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. The minerals were present in 14 of 24 ligament samples, both in stenosis and control groups. The inorganic substance constitutes on average ~0.1% of the sample volume. The minerals are scattered in the soft tissue matrix without any regular pattern. It was confirmed that minerals possess an internal structure and consist of the organic material and small inorganic grains mixture. The physicochemical analyses show that the predominant crystalline phase was hydroxyapatite (HAP). In the stenosis group calcium pyrophosphate dehydrate (CPPD) was identified. Both structures were never present in a single sample. Two different crystal structures suggest two independent processes of mineralization. The formation of CPPD may be treated as a more intense process since CPPD minerals are characterized by bigger values of the structural parameters and higher density than HAP deposits. The formation of HAP minerals is a soft tissue degeneration process that begins, in some cases, at early age or may not occur at all. Various density and volume of mineral grains indicate that the mineralization process does not occur in a constant environment and proceeds with various speeds. The formation of minerals in ligamenta flava is not directly associated with diagnosed spinal canal stenosis.

Detail and gestalt focus in individuals with optimal outcomes from Autism Spectrum Disorders

PubMed Central

Fitch, Allison; Fein, Deborah A.; Eigsti, Inge-Marie

2015-01-01

Individuals with high-functioning autism (HFA) have a cognitive style that privileges local over global or gestalt details. While not a core symptom of autism, individuals with HFA seem to reliably show this bias. Our lab has been studying a sample of children who have overcome their early ASD diagnoses, showing “optimal outcomes” (OO). This study characterizes performance by OO, HFA, and typically developing (TD) adolescents as they describe paintings under cognitive load. Analyses of detail focus in painting descriptions indicated that the HFA group displayed significantly more local focus than both OO and TD groups, while the OO and TD groups did not differ. We discuss implications for the centrality of detail focus to the autism diagnosis. PMID:25563455

Structural characterization of nano-oxide layers in PtMn based specular spin valves

NASA Astrophysics Data System (ADS)

Zhou, Min; Chen, Lifan; Diao, Zhitao; Park, Chang-Man; Huai, Yiming

2005-05-01

A systematic structure characterization of nano-oxide layers (NOLs) and specular spin valves using x-ray diffraction and high-resolution transmission electron microscopy (HRTEM) has been studied. High-angle x-ray diffraction data show almost identical fcc textures for both natural and plasma NOL spin-valves. Low-angle x-ray reflectivity spectrum shows more deteriorated Kiessig fringes at high incident angles for natural oxide sample, indicating rougher interfaces in natural oxidation than in plasma oxidation. Oxygen exposure plays an important role in NOLs process. Fabricating NOLs without any crystal structure degradation is critical to obtain high MR ratio. HRTEM reveals that oxide clusters mixing with insufficiently oxidized CoFe layers prevailed in natural NOL, and the natural oxidation was inhomogeneous. In contrast, plasma NOL has a thinner, more homogeneously oxidized CoFe layers with sharp interfaces. In plasma NOLs, the structures still maintain CoFe crystal structure. The structures and magnetic correlation of the NOL specular spin valves are discussed.

Characterization of structural and electrical properties of ZnO tetrapods

NASA Astrophysics Data System (ADS)

Gu, Yu-Dong; Mai, Wen-Jie; Jiang, Peng

2011-12-01

ZnO tetrapods were synthesized by a typical thermal vapor-solid deposition method in a horizontal tube furnace. Structural characterization was carried out by transmission electron microscopy (TEM) and select-area electron diffraction (SAED), which shows the presence of zinc blende nucleus in the center of tetrapods while the four branches taking hexagonal wurtzite structure. The electrical transport property of ZnO tetrapods was investigated through an in-situ nanoprobe system. The three branches of a tetrapod serve as source, drain, and "gate", respectively; while the fourth branch pointing upward works as the force trigger by vertically applying external force downward. The conductivity of each branch of ZnO-tetrapods increases 3-4 times under pressure. In such situation, the electrical current through the branches of ZnO tetrapods can be tuned by external force, and therefore a simple force sensor based on ZnO tetrapods has been demonstrated for the first time.

Historic American Buildings Survey, A.S. Burns, Photographer December, 1933 DETAIL ...

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

Historic American Buildings Survey, A.S. Burns, Photographer December, 1933 DETAIL OF BRIDGE IN PENNSYLVANIA - Structures on Old National Trail, Bridge, U.S. Route 40, Pittsburgh, Allegheny County, PA

Classification and Dose-Response Characterization of ...

EPA Pesticide Factsheets

Thirty years and over a billion of today’s dollars worth of pesticide registration toxicity studies, historically stored as hardcopy and scanned documents, have been digitized into highly standardized and structured toxicity data, within the U.S. Environmental Protection Agency’s (EPA) Toxicity Reference Database (ToxRefDB). The source toxicity data in ToxRefDB covers multiple study types, including subchronic, developmental, reproductive, chronic, and cancer studies, resulting in a diverse set of endpoints and toxicities. Novel approaches to chemical classification are performed as a model application of ToxRefDB and as an essential need for highly detailed chemical classifications within the EPA’s ToxCast™ research program. In order to develop predictive models and biological signatures utilizing high-throughput screening (HTS) and in vitro genomic data, endpoints and toxicities must first be identified and globally characterized for ToxCast Phase I chemicals. Secondarily, dose-response characterization within and across toxicity endpoints provide insight into key precursor toxicity events and overall endpoint relevance. Toxicity-based chemical classification and dose-response characterization utilizing ToxRefDB prioritized toxicity endpoints and differentiated toxicity outcomes across a large chemical set.

Characterization of the geometry and topology of DNA pictured as a discrete collection of atoms

PubMed Central

Olson, Wilma K.

2014-01-01

The structural and physical properties of DNA are closely related to its geometry and topology. The classical mathematical treatment of DNA geometry and topology in terms of ideal smooth space curves was not designed to characterize the spatial arrangements of atoms found in high-resolution and simulated double-helical structures. We present here new and rigorous numerical methods for the rapid and accurate assessment of the geometry and topology of double-helical DNA structures in terms of the constituent atoms. These methods are well designed for large DNA datasets obtained in detailed numerical simulations or determined experimentally at high-resolution. We illustrate the usefulness of our methodology by applying it to the analysis of three canonical double-helical DNA chains, a 65-bp minicircle obtained in recent molecular dynamics simulations, and a crystallographic array of protein-bound DNA duplexes. Although we focus on fully base-paired DNA structures, our methods can be extended to treat the geometry and topology of melted DNA structures as well as to characterize the folding of arbitrary molecules such as RNA and cyclic peptides. PMID:24791158

Interior detail of south wall with shed roofs showing steel ...

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

Interior detail of south wall with shed roofs showing steel structure, paint room on lower right, view facing west-southwest - U.S. Naval Base, Pearl Harbor, Boat Shop, Seventh Street near Avenue E, Pearl City, Honolulu County, HI

4. DETAIL OF CAST AND WROUGHT IRON RAILING WITH SUPPORTING ...

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

4. DETAIL OF CAST AND WROUGHT IRON RAILING WITH SUPPORTING STRUCTURES AND STEEL BEAM, FROM THE NORTH BANK LOOKING SOUTHEAST AT THE WEST (UPSTREAM) SIDE - Railroad Avenue Bridge, Spanning Mispillion River on Church Street, Milford, Sussex County, DE

View south, wharf B, timber framing, detail of cross bracing, ...

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

View south, wharf B, timber framing, detail of cross bracing, recent galvanized straps, bolts and washers - U.S. Coast Guard Sandy Hook Station, Western Docking Structure, West of intersection of Canfield Road & Hartshorne Drive, Highlands, Monmouth County, NJ

Life-cycle cost as basis to optimize waste collection in space and time: A methodology for obtaining a detailed cost breakdown structure.

PubMed

Sousa, Vitor; Dias-Ferreira, Celia; Vaz, João M; Meireles, Inês

2018-05-01

Extensive research has been carried out on waste collection costs mainly to differentiate costs of distinct waste streams and spatial optimization of waste collection services (e.g. routes, number, and location of waste facilities). However, waste collection managers also face the challenge of optimizing assets in time, for instance deciding when to replace and how to maintain, or which technological solution to adopt. These issues require a more detailed knowledge about the waste collection services' cost breakdown structure. The present research adjusts the methodology for buildings' life-cycle cost (LCC) analysis, detailed in the ISO 15686-5:2008, to the waste collection assets. The proposed methodology is then applied to the waste collection assets owned and operated by a real municipality in Portugal (Cascais Ambiente - EMAC). The goal is to highlight the potential of the LCC tool in providing a baseline for time optimization of the waste collection service and assets, namely assisting on decisions regarding equipment operation and replacement.

Structural and biophysical characterization of an epitope-specific engineered Fab fragment and complexation with membrane proteins: implications for co-crystallization.

PubMed

Johnson, Jennifer L; Entzminger, Kevin C; Hyun, Jeongmin; Kalyoncu, Sibel; Heaner, David P; Morales, Ivan A; Sheppard, Aly; Gumbart, James C; Maynard, Jennifer A; Lieberman, Raquel L

2015-04-01

Crystallization chaperones are attracting increasing interest as a route to crystal growth and structure elucidation of difficult targets such as membrane proteins. While strategies to date have typically employed protein-specific chaperones, a peptide-specific chaperone to crystallize multiple cognate peptide epitope-containing client proteins is envisioned. This would eliminate the target-specific chaperone-production step and streamline the co-crystallization process. Previously, protein engineering and directed evolution were used to generate a single-chain variable (scFv) antibody fragment with affinity for the peptide sequence EYMPME (scFv/EE). This report details the conversion of scFv/EE to an anti-EE Fab format (Fab/EE) followed by its biophysical characterization. The addition of constant chains increased the overall stability and had a negligible impact on the antigen affinity. The 2.0 Å resolution crystal structure of Fab/EE reveals contacts with larger surface areas than those of scFv/EE. Surface plasmon resonance, an enzyme-linked immunosorbent assay, and size-exclusion chromatography were used to assess Fab/EE binding to EE-tagged soluble and membrane test proteins: namely, the β-barrel outer membrane protein intimin and α-helical A2a G protein-coupled receptor (A2aR). Molecular-dynamics simulation of the intimin constructs with and without Fab/EE provides insight into the energetic complexities of the co-crystallization approach.

Analytical characterization and structure elucidation of metabolites from Aspergillus ochraceus MP2 fungi.

PubMed

Meenupriya, J; Thangaraj, M

2011-10-01

To isolate and characterize the bioactive secondary metabolites from Aspergillus ochraceus (A. ochraceus) MP2 fungi. The anti bacterial activity of marine sponge derived fungi A. ochraceus MP2 was thoroughly investigated against antagonistic human pathogens. The optimum inhibitory concentration of the fungi in the elite solvent was also determined. The promising extracts that showed good antimicrobial activity were subjected to further analytical separation to get individual distinct metabolites and the eluants were further identified by GC MS instrumental analysis. The molecular characterization of the elite fungal strains were done by isolating their genomic DNA and amplify the internal transcribed spacer (ITS) region of 5.8s rRNA using specific ITS primer. The novelty of the strain was proved by homology search tools and elite sequences was submitted to GENBANK. Three bioactive compounds were characterized to reveal their identity, chemical formula and structure. The first elutant was identified asα- Campholene aldehyde with chemical formula C10 H16 O and molecular weight 152 Da. The second elutant was identified as Lucenin-2 and chemical formula C27 H30 O16 and molecular weight 610 Da. The third elutant was identified as 6-Ethyloct- 3-yl- 2- ethylhexyl ester with Chemical formula C26 H42 O4 with molecular weight 418 Da. The isolated compounds showed significant antimicrobial activity against potential human pathogens. Microbial secondary metabolites represent a large source of compounds endowed with ingenious structures and potent biological activities.

Characterization of multifunctional structural capacitors for embedded energy storage

NASA Astrophysics Data System (ADS)

Lin, Yirong; Sodano, Henry A.

2009-12-01

Multifunctional composites are a class of materials that combine structural and other functionalities such as sensing, actuation, energy harvesting, and vibration control in order to maximize structural performance while minimizing weight and complexity. Among all the multifunctional composites developed so far, piezoelectric composites have been widely studied due to the high coupling of energy between the electrical and mechanical domains and the inherently high dielectric constant. Several piezoelectric fiber composites have been developed for sensing and actuation applications; however, none of the previously studied composites fully embed all components of an energy storage device as load bearing members of the structure. A multifunctional fiber that can be embedded in a composite material to perform sensing and actuation has been recently developed [Y. Lin and H. A. Sodano, Adv. Funct. Mater. 18, 592 (2008)], in addition to providing load bearing functionality. The design was achieved by coating a common structural fiber, silicon carbide, with a barium titanate piezoelectric shell, and poling the active material radically by employing the structural fiber as one of the electrodes. The silicon carbide core fiber also carries external mechanical loading to protect the brittle barium titanate shell from fracture. The excellent piezoelectric and dielectric properties of the barium titanate material make the active structural fiber an outstanding candidate for converting and storing ambient mechanical energy into electrical energy to power other electric devices in the system. This paper focuses on the characterization of energy storage capability of the multifunctional fiber provided by the dielectric properties of the barium titanate shell. The capacitances of the multifunctional fibers with four different aspect ratios are tested and compared with the theoretical expressions for the cylindrical capacitor, while the breakdown voltages of the multifunctional

9. DETAIL OF UMBILICAL MAST BASE WITH STEEL STOPS AT ...

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

9. DETAIL OF UMBILICAL MAST BASE WITH STEEL STOPS AT EAST END OF MOBILE SERVICE STRUCTURE RAIL; VIEW TO NORTHWEST. - Cape Canaveral Air Station, Launch Complex 17, Facility 28501, East end of Lighthouse Road, Cape Canaveral, Brevard County, FL

Characterizing spatial structure of sediment E. coli populations to inform sampling design.

PubMed

Piorkowski, Gregory S; Jamieson, Rob C; Hansen, Lisbeth Truelstrup; Bezanson, Greg S; Yost, Chris K

2014-01-01

Escherichia coli can persist in streambed sediments and influence water quality monitoring programs through their resuspension into overlying waters. This study examined the spatial patterns in E. coli concentration and population structure within streambed morphological features during baseflow and following stormflow to inform sampling strategies for representative characterization of E. coli populations within a stream reach. E. coli concentrations in bed sediments were significantly different (p = 0.002) among monitoring sites during baseflow, and significant interactive effects (p = 0.002) occurred among monitoring sites and morphological features following stormflow. Least absolute shrinkage and selection operator (LASSO) regression revealed that water velocity and effective particle size (D 10) explained E. coli concentration during baseflow, whereas sediment organic carbon, water velocity and median particle diameter (D 50) were important explanatory variables following stormflow. Principle Coordinate Analysis illustrated the site-scale differences in sediment E. coli populations between disconnected stream segments. Also, E. coli populations were similar among depositional features within a reach, but differed in relation to high velocity features (e.g., riffles). Canonical correspondence analysis resolved that E. coli population structure was primarily explained by spatial (26.9–31.7 %) over environmental variables (9.2–13.1 %). Spatial autocorrelation existed among monitoring sites and morphological features for both sampling events, and gradients in mean particle diameter and water velocity influenced E. coli population structure for the baseflow and stormflow sampling events, respectively. Representative characterization of streambed E. coli requires sampling of depositional and high velocity environments to accommodate strain selectivity among these features owing to sediment and water velocity heterogeneity.

Seeking structural specificity: direct modulation of pentameric ligand-gated ion channels by alcohols and general anesthetics.

PubMed

Howard, Rebecca J; Trudell, James R; Harris, R Adron

2014-01-01

Alcohols and other anesthetic agents dramatically alter neurologic function in a wide range of organisms, yet their molecular sites of action remain poorly characterized. Pentameric ligand-gated ion channels, long implicated in important direct effects of alcohol and anesthetic binding, have recently been illuminated in renewed detail thanks to the determination of atomic-resolution structures of several family members from lower organisms. These structures provide valuable models for understanding and developing anesthetic agents and for allosteric modulation in general. This review surveys progress in this field from function to structure and back again, outlining early evidence for relevant modulation of pentameric ligand-gated ion channels and the development of early structural models for ion channel function and modulation. We highlight insights and challenges provided by recent crystal structures and resulting simulations, as well as opportunities for translation of these newly detailed models back to behavior and therapy.

Seeking Structural Specificity: Direct Modulation of Pentameric Ligand-Gated Ion Channels by Alcohols and General Anesthetics

PubMed Central

Trudell, James R.; Harris, R. Adron

2014-01-01

Alcohols and other anesthetic agents dramatically alter neurologic function in a wide range of organisms, yet their molecular sites of action remain poorly characterized. Pentameric ligand-gated ion channels, long implicated in important direct effects of alcohol and anesthetic binding, have recently been illuminated in renewed detail thanks to the determination of atomic-resolution structures of several family members from lower organisms. These structures provide valuable models for understanding and developing anesthetic agents and for allosteric modulation in general. This review surveys progress in this field from function to structure and back again, outlining early evidence for relevant modulation of pentameric ligand-gated ion channels and the development of early structural models for ion channel function and modulation. We highlight insights and challenges provided by recent crystal structures and resulting simulations, as well as opportunities for translation of these newly detailed models back to behavior and therapy. PMID:24515646

Preliminary Hydrogeologic Characterization Results from the Wallula Basalt Pilot Study

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

B.P. McGrail; E. C. Sullivan; F. A. Spane

2009-12-01

The DOE's Big Sky Regional Carbon Sequestration Partnership has completed drilling the first continental flood basalt sequestration pilot borehole to a total depth (TD) of 4,110 feet on the Boise White Paper Mill property at Wallula, Washington. Site suitability was assessed prior to drilling by the 2007-2008 acquisition, processing and analysis of a four-mile, five-line three component seismic swath, which was processed as a single data-dense line. Analysis of the seismic survey data indicated a composite basalt formation thickness of {approx}8,000 feet and absence of major geologic structures (i.e., faults) along the line imaged by the seismic swath. Drilling ofmore » Wallula pilot borehole was initiated on January 13, 2009 and reached TD on April 6, 2009. Based on characterization results obtained during drilling, three basalt breccia zones were identified between the depth interval of 2,716 and 2,910 feet, as being suitable injection reservoir for a subsequent CO2 injection pilot study. The targeted injection reservoir lies stratigraphically below the massive Umtanum Member of the Grande Ronde Basalt, whose flow-interior section possesses regionally recognized low-permeability characteristics. The identified composite injection zone reservoir provides a unique and attractive opportunity to scientifically study the reservoir behavior of three inter-connected reservoir intervals below primary and secondary caprock confining zones. Drill cuttings, wireline geophysical logs, and 31one-inch diameter rotary sidewall cores provided geologic data for characterization of rock properties. XRF analyses of selected rock samples provided geochemical characterizations of the rocks and stratigraphic control for the basalt flows encountered by the Wallula pilot borehole. Based on the geochemical results, the pilot borehole was terminated in the Wapshilla Ridge 1 flow of the Grande Ronde Basalt Formation. Detailed hydrologic test characterizations of 12 basalt interflow

Production and Structural Characterization of Lactobacillus helveticus Derived Biosurfactant

PubMed Central

Sharma, Deepansh; Saharan, Baljeet Singh; Chauhan, Nikhil; Bansal, Anshul; Procha, Suresh

2014-01-01

A probiotic strain of lactobacilli was isolated from traditional soft Churpi cheese of Yak milk and found positive for biosurfactant production. Lactobacilli reduced the surface tension of phosphate buffer saline (PBS) from 72.0 to 39.5 mNm−1 pH 7.2 and its critical micelle concentration (CMC) was found to be 2.5 mg mL−1. Low cost production of Lactobacilli derived biosurfactant was carried out at lab scale fermenter which yields 0.8 mg mL−1 biosurfactant. The biosurfactant was found least phytotoxic and cytotoxic as compared to the rhamnolipid and sodium dodecyl sulphate (SDS) at different concentration. Structural attributes of biosurfactant were determined by FTIR, NMR (1H and 13C), UPLC-MS, and fatty acid analysis by GCMS which confirmed the presence of glycolipid type of biosurfactant closely similar to xylolipids. Biosurfactant is mainly constituted by lipid and sugar fractions. The present study outcomes provide valuable information on structural characterization of the biosurfactant produced by L. helveticus MRTL91. These findings are encouraging for the application of Lactobacilli derived biosurfactant as nontoxic surface active agents in the emerging field of biomedical applications. PMID:25506070

The influence of cross-order terms in interface mobilities for structure-borne sound source characterization

NASA Astrophysics Data System (ADS)

Bonhoff, H. A.; Petersson, B. A. T.

2010-08-01

For the characterization of structure-borne sound sources with multi-point or continuous interfaces, substantial simplifications and physical insight can be obtained by incorporating the concept of interface mobilities. The applicability of interface mobilities, however, relies upon the admissibility of neglecting the so-called cross-order terms. Hence, the objective of the present paper is to clarify the importance and significance of cross-order terms for the characterization of vibrational sources. From previous studies, four conditions have been identified for which the cross-order terms can become more influential. Such are non-circular interface geometries, structures with distinctively differing transfer paths as well as a suppression of the zero-order motion and cases where the contact forces are either in phase or out of phase. In a theoretical study, the former four conditions are investigated regarding the frequency range and magnitude of a possible strengthening of the cross-order terms. For an experimental analysis, two source-receiver installations are selected, suitably designed to obtain strong cross-order terms. The transmitted power and the source descriptors are predicted by the approximations of the interface mobility approach and compared with the complete calculations. Neglecting the cross-order terms can result in large misinterpretations at certain frequencies. On average, however, the cross-order terms are found to be insignificant and can be neglected with good approximation. The general applicability of interface mobilities for structure-borne sound source characterization and the description of the transmission process thereby is confirmed.

9. UPSTREAM EXTENSION TO 60' INFILTRATION PIPE: REINFORCEMENT DETAILS OF ...

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

9. UPSTREAM EXTENSION TO 60' INFILTRATION PIPE: REINFORCEMENT DETAILS OF VALVE CONTROL STRUCTURE. Sheet A-20, July, 1939. File no. SA 342/29. - Prado Dam, Embankment, Santa Ana River near junction of State Highways 71 & 91, Corona, Riverside County, CA

9. Detail of a typical window and a ventilator just ...

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

9. Detail of a typical window and a ventilator just below the window sill - the only instance of such placement of this feature in the structure. - Perry Township School No. 3, Middle Mount Vernon & Eickhoff Roads, Evansville, Vanderburgh County, IN

Integrated Surface and Mechanical Characterization of Freestanding Biological and Other Nano-Structures Using Atomic Force Microscopy

NASA Astrophysics Data System (ADS)

Wang, Xin

This dissertation is focused on surface and mechanical characterization of freestanding biological and other nano-structures using atomic force microscopy including two parts: cell mechanics and nano-structure mechanics. The main purpose of this work is to investigate how the nano- / micro-scale mechanical properties affect macro-scale function. In cancer cells, efficacy of drug delivery is oftentimes declined due to the thick dendritic network of oligosaccharide mucin chains on the cell surface. AFM is used to measure the force needed to pierce the mucin layer to reach the cell surface. A pool of ovarian, pancreatic, lung, colorectal and breast cancer cells are characterized. The studies offer additional support for the development of clinical and pharmaceutical approaches to combat mucin over-expression in tumors during cancer chemotherapy. Macroscopic adhesion-aggregation and subsequent transportation of microorganisms in porous medium are closely related to the microscopic deformation and adhesion mechanical properties. The classical Tabor's parameter is modified. Multiple bacterial strains are characterized in terms of aggregates size, aggregation index and transportation kinetics. AFM is employed to obtain the microscopic coupled adhesion-deformation properties. The strong correlation between Tabor's parameter and aggregation-deposition-transportation suggests the AFM characterization is capable of making reliable predication of macroscopic behavior. A novel "nano-cheese-cutter" is fabricated on tipless AFM cantilever to measure elastic modulus and interfacial adhesion of a 1-D freestanding nano-structure. A single electrospun fiber is attached to the free end of AFM cantilever, while another fiber is similarly prepared on a mica substrate in an orthogonal direction. An external load is applied to deform the two fibers into complementary V-shapes. This work is extended to investigate the interfacial adhesion energy between dissimilar materials. SWCNT thin

A detailed X-ray investigation of ζ Puppis. IV. Further characterization of the variability

NASA Astrophysics Data System (ADS)

Nazé, Yaël; Ramiaramanantsoa, Tahina; Stevens, Ian R.; Howarth, Ian D.; Moffat, Anthony F. J.

2018-01-01

Context. One of the optically brightest and closest massive stars, ζ Pup, is also a bright X-ray source. Previously, its X-ray emission was found to be variable with light curves harbouring "trends" with a typical timescale longer than the exposure length, i.e. >1 d. The origin of these changes was proposed to be linked to large-scale structures in the wind of ζ Pup, but further characterization of the variability at high energies was needed to investigate this scenario. Aims: Since the previous papers of this series, a number of new X-ray observations have become available. Furthermore, a cyclic behaviour with a 1.78 d period was identified in long optical photometric runs, which is thought to be associated with the launching mechanism of large-scale wind structures. Methods: We analysed these new X-ray data, revisited the old data, and compared the X-ray light curves with the optical data, notably those taken simultaneously. Results: The behaviour of ζ Pup in X-rays cannot be explained in terms of a perfect clock because the amplitude and shape of its variations change with time. For example, ζ Pup was much more strongly variable between 2007 and 2011 than before and after this interval. Comparing the X-ray spectra of the star at maximum and minimum brightness yields no compelling difference beyond the overall flux change: the temperatures, absorptions, and line shapes seem to remain constant, well within errors. The only common feature between X-ray datasets is that the variation amplitudes appear maximum in the medium (0.6-1.2 keV) energy band. Finally, no clear and coherent correlation can be found between simultaneous X-ray and optical data. Only a subgroup of observations may be combined coherently with the optical period of 1.78 d, although the simultaneous optical behaviour is unknown. Conclusions: The currently available data do not reveal any obvious, permanent, and direct correlation between X-ray and optical variations. The origin of the X

Characterization of mechanical properties of lamellar structure of the aortic wall: Effect of aging.

PubMed