Spatial confinement governs orientational order in patchy particles

NASA Astrophysics Data System (ADS)

Iwashita, Yasutaka; Kimura, Yasuyuki

2016-06-01

Orientational order in condensed matter plays a key role in determining material properties such as ferromagnetism, viscoelasticity or birefringence. We studied purely orientational ordering in closely-packed one-patch colloidal particles confined between flat substrates, where the particles can only rotate and are ordered via the sticky interaction between the patches. For the first time, we experimentally realized a rich variety of mesoscopic patterns through orientational ordering of colloids by controlling patch size and confinement thickness. The combination of experiment and numerical simulation reveals the decisive role of confinement: An ordered state(s) is selected from the (meta)stable options in bulk when it is commensurate with the system geometry and boundary conditions; otherwise, frustration induces a unique order. Our study offers a new means of systematic control over mesoscopic structures via orientational ordering in patchy particles. The system would also possess unique functionalities through the rotational response of the particles to external stimuli.

New aromatic activated dihalides and bisphenol monomers for the preparation of novel poly(arylene ethers)

NASA Technical Reports Server (NTRS)

Wolfe, James F.

1993-01-01

The goal of this research program was to synthesize a series of unique monomers of type I to be utilized at NASA-Langley in the preparation of new poly(arylene ether ketones), poly(arylene ether ketosulfones), and poly(arylene ether ketophosphine oxides). These A-A and A-B monomer systems, which possess activated aryl halide and/or phenolic end groups, are accessible via condensation reactions of appropriately substituted aryl acetonitrile carbanions with activated aryl dihalides followed by oxidative decyanation.

The Staphylococcus aureus autoinducer-2 synthase LuxS is regulated by Ser/Thr phosphorylation.

PubMed

Cluzel, Marie-Eve; Zanella-Cléon, Isabelle; Cozzone, Alain J; Fütterer, Klaus; Duclos, Bertrand; Molle, Virginie

2010-12-01

The Staphylococcus aureus autoinducer-2 (AI-2) producer protein LuxS is phosphorylated by the Ser/Thr kinase Stk1 at a unique position, Thr14. The enzymatic activity of the phosphorylated isoform of LuxS was abrogated compared to that of nonphosphorylated LuxS, thus providing the first evidence of an AI-2-producing enzyme regulated by phosphorylation and demonstrating that S. aureus possesses an original and specific system for controlling AI-2 synthesis.

The Staphylococcus aureus Autoinducer-2 Synthase LuxS Is Regulated by Ser/Thr Phosphorylation▿

PubMed Central

Cluzel, Marie-Eve; Zanella-Cléon, Isabelle; Cozzone, Alain J.; Fütterer, Klaus; Duclos, Bertrand; Molle, Virginie

2010-01-01

The Staphylococcus aureus autoinducer-2 (AI-2) producer protein LuxS is phosphorylated by the Ser/Thr kinase Stk1 at a unique position, Thr14. The enzymatic activity of the phosphorylated isoform of LuxS was abrogated compared to that of nonphosphorylated LuxS, thus providing the first evidence of an AI-2-producing enzyme regulated by phosphorylation and demonstrating that S. aureus possesses an original and specific system for controlling AI-2 synthesis. PMID:20870760

Pediatric emergencies.

PubMed

Ryan, Erin

2015-03-01

It is important that pediatric critical care nurses possess a thorough understanding of their patient and be able to provide exceptional care, especially during emergent situations in the operating room. This care is accomplished by assessing the pediatric patient, dosing medications accurately and effectively, and performing effective Pediatric Advanced Life Support. Pediatric patients present with unique anatomy, physiology, and pathophysiology. Emergencies are reviewed according to organ system, with a focus on definition, presentation, pathophysiology, management, and special considerations. Copyright © 2015 Elsevier Inc. All rights reserved.

Support effects in catalysis studied by in-situ sum frequency generation vibrational spectroscopy and in-situ x-ray spectroscopies

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

Kennedy, Griffin John

Here, kinetic measurements are paired with in-situ spectroscopic characterization tools to investigate colloidally based, supported Pt catalytic model systems in order to elucidate the mechanisms by which metal and support work in tandem to dictate activity and selectivity. The results demonstrate oxide support materials, while inactive in absence of Pt nanoparticles, possess unique active sites for the selective conversion of gas phase molecules when paired with an active metal catalyst.

How early ferns became trees.

PubMed

Galtier, J; Hueber, F M

2001-09-22

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest tree-fern known to date. The potential of this primitive zygopterid fern to produce such an unusual growth form-without real equivalent among living plants-is related to the possession of two kinds of roots that have complementary functional roles: (i) large roots produced by stems with immediate positive geotropism, strongly adapted to mechanical support and water uptake from the soil; and (ii) small roots borne either on large roots or on petiole bases for absorbing humidity inside the false trunk.

Gun Possession among American Youth: A Discovery-Based Approach to Understand Gun Violence

PubMed Central

Ruggles, Kelly V.; Rajan, Sonali

2014-01-01

Objective To apply discovery-based computational methods to nationally representative data from the Centers for Disease Control and Preventions’ Youth Risk Behavior Surveillance System to better understand and visualize the behavioral factors associated with gun possession among adolescent youth. Results Our study uncovered the multidimensional nature of gun possession across nearly five million unique data points over a ten year period (2001–2011). Specifically, we automated odds ratio calculations for 55 risk behaviors to assemble a comprehensive table of associations for every behavior combination. Downstream analyses included the hierarchical clustering of risk behaviors based on their association “fingerprint” to 1) visualize and assess which behaviors frequently co-occur and 2) evaluate which risk behaviors are consistently found to be associated with gun possession. From these analyses, we identified more than 40 behavioral factors, including heroin use, using snuff on school property, having been injured in a fight, and having been a victim of sexual violence, that have and continue to be strongly associated with gun possession. Additionally, we identified six behavioral clusters based on association similarities: 1) physical activity and nutrition; 2) disordered eating, suicide and sexual violence; 3) weapon carrying and physical safety; 4) alcohol, marijuana and cigarette use; 5) drug use on school property and 6) overall drug use. Conclusions Use of computational methodologies identified multiple risk behaviors, beyond more commonly discussed indicators of poor mental health, that are associated with gun possession among youth. Implications for prevention efforts and future interdisciplinary work applying computational methods to behavioral science data are described. PMID:25372864

Gun possession among American youth: a discovery-based approach to understand gun violence.

PubMed

Ruggles, Kelly V; Rajan, Sonali

2014-01-01

To apply discovery-based computational methods to nationally representative data from the Centers for Disease Control and Preventions' Youth Risk Behavior Surveillance System to better understand and visualize the behavioral factors associated with gun possession among adolescent youth. Our study uncovered the multidimensional nature of gun possession across nearly five million unique data points over a ten year period (2001-2011). Specifically, we automated odds ratio calculations for 55 risk behaviors to assemble a comprehensive table of associations for every behavior combination. Downstream analyses included the hierarchical clustering of risk behaviors based on their association "fingerprint" to 1) visualize and assess which behaviors frequently co-occur and 2) evaluate which risk behaviors are consistently found to be associated with gun possession. From these analyses, we identified more than 40 behavioral factors, including heroin use, using snuff on school property, having been injured in a fight, and having been a victim of sexual violence, that have and continue to be strongly associated with gun possession. Additionally, we identified six behavioral clusters based on association similarities: 1) physical activity and nutrition; 2) disordered eating, suicide and sexual violence; 3) weapon carrying and physical safety; 4) alcohol, marijuana and cigarette use; 5) drug use on school property and 6) overall drug use. Use of computational methodologies identified multiple risk behaviors, beyond more commonly discussed indicators of poor mental health, that are associated with gun possession among youth. Implications for prevention efforts and future interdisciplinary work applying computational methods to behavioral science data are described.

Survey on multisensory feedback virtual reality dental training systems.

PubMed

Wang, D; Li, T; Zhang, Y; Hou, J

2016-11-01

Compared with traditional dental training methods, virtual reality training systems integrated with multisensory feedback possess potentials advantages. However, there exist many technical challenges in developing a satisfactory simulator. In this manuscript, we systematically survey several current dental training systems to identify the gaps between the capabilities of these systems and the clinical training requirements. After briefly summarising the components, functions and unique features of each system, we discuss the technical challenges behind these systems including the software, hardware and user evaluation methods. Finally, the clinical requirements of an ideal dental training system are proposed. Future research/development areas are identified based on an analysis of the gaps between current systems and clinical training requirements. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Unraveling the evolution of uniquely human cognition.

PubMed

MacLean, Evan L

2016-06-07

A satisfactory account of human cognitive evolution will explain not only the psychological mechanisms that make our species unique, but also how, when, and why these traits evolved. To date, researchers have made substantial progress toward defining uniquely human aspects of cognition, but considerably less effort has been devoted to questions about the evolutionary processes through which these traits have arisen. In this article, I aim to link these complementary aims by synthesizing recent advances in our understanding of what makes human cognition unique, with theory and data regarding the processes of cognitive evolution. I review evidence that uniquely human cognition depends on synergism between both representational and motivational factors and is unlikely to be accounted for by changes to any singular cognitive system. I argue that, whereas no nonhuman animal possesses the full constellation of traits that define the human mind, homologies and analogies of critical aspects of human psychology can be found in diverse nonhuman taxa. I suggest that phylogenetic approaches to the study of animal cognition-which can address questions about the selective pressures and proximate mechanisms driving cognitive change-have the potential to yield important insights regarding the processes through which the human cognitive phenotype evolved.

Water-driven actuation of Ornithoctonus huwena spider silk fibers

NASA Astrophysics Data System (ADS)

Lin, Shuyuan; Zhu, Jia; Li, Xinming; Guo, Yang; Fang, Yaopeng; Cheng, Huanyu; Zhu, Hongwei

2017-01-01

Spider silk possesses remarkable mechanical properties and can lift weight effectively. Certain kinds of spider silk have unique response to liquid, especially water, because of their hydrophilic proteins, β-sheet characters, and surface structure. The Ornithoctonus huwena (O. huwena) spider is a unique species because it can be bred artificially and it spins silk whose diameter is in nanometer scale. In this work, we report the "shrink-stretch" behavior of the O. huwena spider silk fibers and show how they can be actuated by water to lift weight over long distance, at a fast speed, and with high efficiency. We further rationalize this behavior by analyzing the mechanical energy of the system. The lifting process is energy-efficient and environmentally friendly, allowing applications in actuators, biomimetic muscles, or hoisting devices.

Navier-Stokes-Voigt Equations with Memory in 3D Lacking Instantaneous Kinematic Viscosity

NASA Astrophysics Data System (ADS)

Di Plinio, Francesco; Giorgini, Andrea; Pata, Vittorino; Temam, Roger

2018-04-01

We consider a Navier-Stokes-Voigt fluid model where the instantaneous kinematic viscosity has been completely replaced by a memory term incorporating hereditary effects, in presence of Ekman damping. Unlike the classical Navier-Stokes-Voigt system, the energy balance involves the spatial gradient of the past history of the velocity rather than providing an instantaneous control on the high modes. In spite of this difficulty, we show that our system is dissipative in the dynamical systems sense and even possesses regular global and exponential attractors of finite fractal dimension. Such features of asymptotic well-posedness in absence of instantaneous high modes dissipation appear to be unique within the realm of dynamical systems arising from fluid models.

Crystallographic phase induced electro-optic properties of nanorod blend nematic liquid crystal.

PubMed

Kundu, Sudarshan; Hill, Jonathan P; Richards, Gary J; Ariga, Katsuhiko; Khan, Ali Hossain; Thupakula, Umamahesh; Acharya, Somobrata

2011-09-01

Ultrasmall ZnS or PbS nanorods encapsulated in fluid-like soft organic surfactants show excellent miscibility in the nematic liquid crystal (LC ZLI-4792) host resulting in a novel soft matter type blend with enhanced electro-optic properties. The ultranarrow ZnS rods are of wurtzite phase and possess a chemical bipolarity and a net dipole moment. The centrosymmetric ultranarrow PbS rods possess a finite size and shape dependent inherent dipole moment despite their cubic rock-salt structure. When an electric field is applied, the blend aligns along the direction of the field producing a local unidirectional orientation of the rods and LC directors, and defining a unique axis for the system. The local ordering significantly affects the global ordering of the blend allowing a more rapid response of the electro-optic properties. The degree and switching speed of the blends depend upon the magnitude of dipole moments present in the dopant nanorods. We show how a non-mesogenic element designed with preferential crystallographic phase can be introduced within a LC for improvement of the switching properties of the LC blend. These types of unique blends are a model for fundamental conceptual advances in general understanding of interaction behaviour leading consequently to a significant technological advancement for superior device fabrication.

Reassessment of the Evidence for Postcranial Skeletal Pneumaticity in Triassic Archosaurs, and the Early Evolution of the Avian Respiratory System

PubMed Central

Butler, Richard J.; Barrett, Paul M.; Gower, David J.

2012-01-01

Uniquely among extant vertebrates, birds possess complex respiratory systems characterised by the combination of small, rigid lungs, extensive pulmonary air sacs that possess diverticula that invade (pneumatise) the postcranial skeleton, unidirectional ventilation of the lungs, and efficient crosscurrent gas exchange. Crocodilians, the only other living archosaurs, also possess unidirectional lung ventilation, but lack true air sacs and postcranial skeletal pneumaticity (PSP). PSP can be used to infer the presence of avian-like pulmonary air sacs in several extinct archosaur clades (non-avian theropod dinosaurs, sauropod dinosaurs and pterosaurs). However, the evolution of respiratory systems in other archosaurs, especially in the lineage leading to crocodilians, is poorly documented. Here, we use µCT-scanning to investigate the vertebral anatomy of Triassic archosaur taxa, from both the avian and crocodilian lineages as well as non-archosaurian diapsid outgroups. Our results confirm previous suggestions that unambiguous evidence of PSP (presence of internal pneumatic cavities linked to the exterior by foramina) is found only in bird-line (ornithodiran) archosaurs. We propose that pulmonary air sacs were present in the common ancestor of Ornithodira and may have been subsequently lost or reduced in some members of the clade (notably in ornithischian dinosaurs). The development of these avian-like respiratory features might have been linked to inferred increases in activity levels among ornithodirans. By contrast, no crocodile-line archosaur (pseudosuchian) exhibits evidence for unambiguous PSP, but many of these taxa possess the complex array of vertebral laminae and fossae that always accompany the presence of air sacs in ornithodirans. These laminae and fossae are likely homologous with those in ornithodirans, which suggests the need for further investigation of the hypothesis that a reduced, or non-invasive, system of pulmonary air sacs may be have been present in these taxa (and secondarily lost in extant crocodilians) and was potentially primitive for Archosauria as a whole. PMID:22470520

Biogenic twinned crystals exhibiting unique morphological symmetry

NASA Astrophysics Data System (ADS)

Hirsch, Anna; Gur, Dvir; Palmer, Ben; Addadi, Lia; Leiserowitz, Leslie; Kronik, Leeor

Guanine crystals are widely used in nature as components of multilayer reflectors. Organisms control the size, morphology, and arrangement of these crystals, to obtain a variety of optical ''devices''. The reflection systems found in the lens of the scallop eye and in the copepod cuticle are unique in that the multilayered reflectors are tiled together to form a contiguous packed array. In the former, square crystals are tiled to form a reflecting mirror. In the latter, hexagonal crystals are closely packed to produce brilliant colors. Based on electron diffraction, morphology considerations, and density functional theory, these crystals were shown to possess similar monoclinic crystal symmetry, which we have previously identified as different from that of synthetic anhydrous guanine. However, the crystals are different in that multiple twinning about the {012} and the {011} crystallographic planes results in square and hexagonal morphology, respectively. This is a unique example where controlled twinning is used as a strategy to form a morphology with higher symmetry than that of the underlying crystal, allowing for tilling that facilitates optical functionality.

32 CFR 104.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... requirement in which the incumbent must gain the necessary experience to qualify for key senior leadership... incumbent possesses unique knowledge, extensive experience, and specialty skill training to successfully...

Electromagnetically Induced Transparency In Rydberg Atomic Medium

NASA Astrophysics Data System (ADS)

Deng, Li; Cong, Lu; Chen, Ai-Xi

2018-03-01

Due to possessing big principal quantum number, Rydberg atom has some unique properties, for example: its radiative lifetime is long, dipole moment is large, and interaction between atoms is strong and so on. These properties make one pay attention to Rydberg atoms. In this paper we investigate the effects of Rydberg dipole-dipole interactions on electromagnetically induced transparency (EIT) schemes and group velocity in three-level systems of ladder type, which provides theoretical foundation for exploring the linear and nonlinear characteristics of light in a Rydberg electromagnetically-induced-transparency medium.

Understanding Leadership

DTIC Science & Technology

2011-02-16

this paper, myths about great men, genetic inheritance, God -given charisma, and so forth, have endured and filled Army stories for years. This paper...leader possesses unique, even God -given,40 traits that somehow separates those who lead 15 and those who do not. This paper thus argues that good...look at other kinds of leaders, such as Albert Einstein . Even though he possessed few of the traits found in FM 6-22 (and therefore would probably not

Holographic nondestructive tests performed on composite samples of ceramic-epoxy-fiberglass sandwich structure

NASA Technical Reports Server (NTRS)

Kurtz, R. L.; Liu, H. K.

1974-01-01

When a hologram storing more than one wave is illuminated with coherent light, the reconstructed wave fronts interfere with each other or with any other phase-related wave front derived from the illuminating source. This multiple wave front comparison is called holographic interferometry, and its application is called holographic nondestructive testing (HNDT). The theoretical aspects of HNDT techniques and the sensitivity of the holographic system to the geometrical placement of the optical components are briefly discussed. A unique HNDT system which is mobile and possesses variable sensitivity to stress amplitude is discribed, the experimental evidence of the application of this system to the testing of the hidden debonds in a ceramic-epoxy-fiberglass structure used for sample testing of the radome of the Pershing missile system is presented.

Fungal Survival in a Chemosynthetic Ecosystem

NASA Astrophysics Data System (ADS)

Kiel Reese, B.; Sobol, M. S.; Hoshino, T.; Inagaki, F.; Eder, E.; Nicora, C. D.; Heyman, H. M.; Kyle, J. E.; Hoyt, D. W.; Tfaily, M. M.; Metz, T. O.

2018-05-01

Fungi possess metabolic pathways capable of utilizing previously considered non-bioavailable energy reserves. Metabolically active fungi occupy a unique niche within the subsurface, providing an organic carbon source for heterotrophic prokaryotes.

IMAGE 100: The interactive multispectral image processing system

NASA Technical Reports Server (NTRS)

Schaller, E. S.; Towles, R. W.

1975-01-01

The need for rapid, cost-effective extraction of useful information from vast quantities of multispectral imagery available from aircraft or spacecraft has resulted in the design, implementation and application of a state-of-the-art processing system known as IMAGE 100. Operating on the general principle that all objects or materials possess unique spectral characteristics or signatures, the system uses this signature uniqueness to identify similar features in an image by simultaneously analyzing signatures in multiple frequency bands. Pseudo-colors, or themes, are assigned to features having identical spectral characteristics. These themes are displayed on a color CRT, and may be recorded on tape, film, or other media. The system was designed to incorporate key features such as interactive operation, user-oriented displays and controls, and rapid-response machine processing. Owing to these features, the user can readily control and/or modify the analysis process based on his knowledge of the input imagery. Effective use can be made of conventional photographic interpretation skills and state-of-the-art machine analysis techniques in the extraction of useful information from multispectral imagery. This approach results in highly accurate multitheme classification of imagery in seconds or minutes rather than the hours often involved in processing using other means.

The influence of and the identification of nonlinearity in flexible structures

NASA Technical Reports Server (NTRS)

Zavodney, Lawrence D.

1988-01-01

Several models were built at NASA Langley and used to demonstrate the following nonlinear behavior: internal resonance in a free response, principal parametric resonance and subcritical instability in a cantilever beam-lumped mass structure, combination resonance in a parametrically excited flexible beam, autoparametric interaction in a two-degree-of-freedom system, instability of the linear solution, saturation of the excited mode, subharmonic bifurcation, and chaotic responses. A video tape documenting these phenomena was made. An attempt to identify a simple structure consisting of two light-weight beams and two lumped masses using the Eigensystem Realization Algorithm showed the inherent difficulty of using a linear based theory to identify a particular nonlinearity. Preliminary results show the technique requires novel interpretation, and hence may not be useful for structural modes that are coupled by a guadratic nonlinearity. A literature survey was also completed on recent work in parametrically excited nonlinear system. In summary, nonlinear systems may possess unique behaviors that require nonlinear identification techniques based on an understanding of how nonlinearity affects the dynamic response of structures. In this was, the unique behaviors of nonlinear systems may be properly identified. Moreover, more accutate quantifiable estimates can be made once the qualitative model has been determined.

Education for Global Survival: Reflections Based on Some Swedish Experiences and Examples. Peace Education Miniprints, No. 33.

ERIC Educational Resources Information Center

Thelin, Bengt

This document which reviews peace education as the subject was presented in Sweden in the later 1980s. The paper argues for a stronger commitment to peace education and approaching the subject from the perspectives of the unique, the absurd, and the relevant. The contemporary era is unique in that humanity now possesses the means to reify…

A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG.

PubMed

Rumfelt, L L; Avila, D; Diaz, M; Bartl, S; McKinney, E C; Flajnik, M F

2001-02-13

In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM(1gj), from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells ("germline-joined"). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H(1gj) in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H(1gj) chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM(1gj). Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system.

Novel polyelectrolyte complex based carbon nanotube composite architectures

NASA Astrophysics Data System (ADS)

Razdan, Sandeep

This study focuses on creating novel architectures of carbon nanotubes using polyelectrolytes. Polyelectrolytes are unique polymers possessing resident charges on the macromolecular chains. This property, along with their biocompatibility (true for most polymers used in this study) makes them ideal candidates for a variety of applications such as membranes, drug delivery systems, scaffold materials etc. Carbon nanotubes are also unique one-dimensional nanoscale materials that possess excellent electrical, mechanical and thermal properties owing to their small size, high aspect ratio, graphitic structure and strength arising from purely covalent bonds in the molecular structure. The present study tries to investigate the synthesis processes and material properties of carbon nanotube composites comprising of polyelectrolyte complexes. Carbon nanotubes are dispersed in a polyelectrolyte and are induced into taking part in a complexation process with two oppositely charged polyelectrolytes. The resulting stoichiometric precipitate is then drawn into fiber form and dried as such. The material properties of the carbon nanotube fibers were characterized and related to synthesis parameters and material interactions. Also, an effort was made to understand and predict fiber morphology resulting from the complexation and drawing process. The study helps to delineate the synthesis and properties of the said polyelectrolyte complex-carbon nanotube architectures and highlights useful properties, such as electrical conductivity and mechanical strength, which could make these structures promising candidates for a variety of applications.

Unique system of FE/PD for magneto-optical recording and magnetic switching devices

DOEpatents

Liu, Chian Q.; Bader, Samuel D.

1992-01-01

A high density magneto-optical information storage medium utilizing the properties of an ultrathin iron film on a palladium substrate. The present invention comprises a magneto-optical medium capable of thermal and magnetic stability and capable of possessing a vertical orientation of the magnetization vector for the magnetic material. Data storage relies on the temperature dependence of the coercivity of the ultrathin film. Data retrieval derives from the Kerr effect which describes the direction of rotation of a plane of polarized light traversing the ultrathin magnetic material as a function of the orientation of the magnetization vector.

Reflectin as a Material for Neural Stem Cell Growth

PubMed Central

2015-01-01

Cephalopods possess remarkable camouflage capabilities, which are enabled by their complex skin structure and sophisticated nervous system. Such unique characteristics have in turn inspired the design of novel functional materials and devices. Within this context, recent studies have focused on investigating the self-assembly, optical, and electrical properties of reflectin, a protein that plays a key role in cephalopod structural coloration. Herein, we report the discovery that reflectin constitutes an effective material for the growth of human neural stem/progenitor cells. Our findings may hold relevance both for understanding cephalopod embryogenesis and for developing improved protein-based bioelectronic devices. PMID:26703760

Analysis of photonic band gap in novel piezoelectric photonic crystal

NASA Astrophysics Data System (ADS)

Malar Kodi, A.; Doni Pon, V.; Joseph Wilson, K. S.

2018-03-01

The transmission properties of one-dimensional novel photonic crystal having silver-doped novel piezoelectric superlattice and air as the two constituent layers have been investigated by means of transfer matrix method. By changing the appropriate thickness of the layers and filling factor of nanocomposite system, the variation in the photonic band gap can be studied. It is found that the photonic band gap increases with the filling factor of the metal nanocomposite and with the thickness of the layer. These structures possess unique characteristics enabling one to operate as optical waveguides, selective filters, optical switches, integrated piezoelectric microactuators, etc.

Recognition and Degradation of Plant Cell Wall Polysaccharides by Two Human Gut Symbionts

PubMed Central

Chiang, Herbert; Pudlo, Nicholas A.; Wu, Meng; McNulty, Nathan P.; Abbott, D. Wade; Henrissat, Bernard; Gilbert, Harry J.; Bolam, David N.; Gordon, Jeffrey I.

2011-01-01

Symbiotic bacteria inhabiting the human gut have evolved under intense pressure to utilize complex carbohydrates, primarily plant cell wall glycans in our diets. These polysaccharides are not digested by human enzymes, but are processed to absorbable short chain fatty acids by gut bacteria. The Bacteroidetes, one of two dominant bacterial phyla in the adult gut, possess broad glycan-degrading abilities. These species use a series of membrane protein complexes, termed Sus-like systems, for catabolism of many complex carbohydrates. However, the role of these systems in degrading the chemically diverse repertoire of plant cell wall glycans remains unknown. Here we show that two closely related human gut Bacteroides, B. thetaiotaomicron and B. ovatus, are capable of utilizing nearly all of the major plant and host glycans, including rhamnogalacturonan II, a highly complex polymer thought to be recalcitrant to microbial degradation. Transcriptional profiling and gene inactivation experiments revealed the identity and specificity of the polysaccharide utilization loci (PULs) that encode individual Sus-like systems that target various plant polysaccharides. Comparative genomic analysis indicated that B. ovatus possesses several unique PULs that enable degradation of hemicellulosic polysaccharides, a phenotype absent from B. thetaiotaomicron. In contrast, the B. thetaiotaomicron genome has been shaped by increased numbers of PULs involved in metabolism of host mucin O-glycans, a phenotype that is undetectable in B. ovatus. Binding studies of the purified sensor domains of PUL-associated hybrid two-component systems in conjunction with transcriptional analyses demonstrate that complex oligosaccharides provide the regulatory cues that induce PUL activation and that each PUL is highly specific for a defined cell wall polymer. These results provide a view of how these species have diverged into different carbohydrate niches by evolving genes that target unique suites of available polysaccharides, a theme that likely applies to disparate bacteria from the gut and other habitats. PMID:22205877

Profiling of Intracellular Metabolites: An Approach to Understanding the Characteristic Physiology of Mycobacterium leprae

PubMed Central

Miyamoto, Yuji; Mukai, Tetsu; Matsuoka, Masanori; Kai, Masanori; Maeda, Yumi; Makino, Masahiko

2016-01-01

Mycobacterium leprae is the causative agent of leprosy and also known to possess unique features such as inability to proliferate in vitro. Among the cellular components of M. leprae, various glycolipids present on the cell envelope are well characterized and some of them are identified to be pathogenic factors responsible for intracellular survival in host cells, while other intracellular metabolites, assumed to be associated with basic physiological feature, remain largely unknown. In the present study, to elucidate the comprehensive profile of intracellular metabolites, we performed the capillary electrophoresis-mass spectrometry (CE-MS) analysis on M. leprae and compared to that of M. bovis BCG. Interestingly, comparison of these two profiles showed that, in M. leprae, amino acids and their derivatives are significantly accumulated, but most of intermediates related to central carbon metabolism markedly decreased, implying that M. leprae possess unique metabolic features. The present study is the first report demonstrating the unique profiles of M. leprae metabolites and these insights might contribute to understanding undefined metabolism of M. leprae as well as pathogenic characteristics related to the manifestation of the disease. PMID:27479467

Profiling of Intracellular Metabolites: An Approach to Understanding the Characteristic Physiology of Mycobacterium leprae.

PubMed

Miyamoto, Yuji; Mukai, Tetsu; Matsuoka, Masanori; Kai, Masanori; Maeda, Yumi; Makino, Masahiko

2016-08-01

Mycobacterium leprae is the causative agent of leprosy and also known to possess unique features such as inability to proliferate in vitro. Among the cellular components of M. leprae, various glycolipids present on the cell envelope are well characterized and some of them are identified to be pathogenic factors responsible for intracellular survival in host cells, while other intracellular metabolites, assumed to be associated with basic physiological feature, remain largely unknown. In the present study, to elucidate the comprehensive profile of intracellular metabolites, we performed the capillary electrophoresis-mass spectrometry (CE-MS) analysis on M. leprae and compared to that of M. bovis BCG. Interestingly, comparison of these two profiles showed that, in M. leprae, amino acids and their derivatives are significantly accumulated, but most of intermediates related to central carbon metabolism markedly decreased, implying that M. leprae possess unique metabolic features. The present study is the first report demonstrating the unique profiles of M. leprae metabolites and these insights might contribute to understanding undefined metabolism of M. leprae as well as pathogenic characteristics related to the manifestation of the disease.

To be at the right place at the right time

PubMed Central

2011-01-01

Aim To analyze the hypothesis of events or neighborhood interactions that is based upon recognizable structures of systems which possess a surface in a four dimensional space - time constellation {x, y, z, t}. To include the theory of hierarchic order of structures and aspects of thermodynamically open systems, especially entropy, structural entropy and entropy flow. Hypothesis Any structure is a space - time constellation that occupies a unique space in its environment. The environment can be a system too, and is assumed to be (nearly) constant. Structures can interact in their environment and create a new structure at a higher order level. Interacting structures that create a surface are called a system. Starting from the bottom, such a system is characterized by its inner structures, its surface function, and its neighborhood. Interaction with a neighboring system is called an event. An event can alter a system, create new systems or induce the decay of a system, dependent upon the surrounding lower level system (background). Results The hypothesis results in a uniform theory about matter, life, diseases, or behavior. Concrete applications permit the estimation of duration of life in man, for example the effect of solid cancer in man, or appearance of protozoans in sexual or asexual reduplication. In addition, it can successfully describe the development of the universe (small exceed of matter above antimatter at the big bang), or the increase of structures (and systems) with increasing time (development of intelligent systems). The three dimensional space possesses the lowest number of mandatory dimensions to implement such a system. PMID:21781323

To be at the right place at the right time.

PubMed

Kayser, Klaus; Borkenfeld, Stephan; Goldmann, Torsten; Kayser, Gian

2011-07-22

To analyze the hypothesis of events or neighborhood interactions that is based upon recognizable structures of systems which possess a surface in a four dimensional space-time constellation {x, y, z, t}. To include the theory of hierarchic order of structures and aspects of thermodynamically open systems, especially entropy, structural entropy and entropy flow. Any structure is a space-time constellation that occupies a unique space in its environment. The environment can be a system too, and is assumed to be (nearly) constant. Structures can interact in their environment and create a new structure at a higher order level. Interacting structures that create a surface are called a system. Starting from the bottom, such a system is characterized by its inner structures, its surface function, and its neighborhood. Interaction with a neighboring system is called an event. An event can alter a system, create new systems or induce the decay of a system, dependent upon the surrounding lower level system (background). The hypothesis results in a uniform theory about matter, life, diseases, or behavior. Concrete applications permit the estimation of duration of life in man, for example the effect of solid cancer in man, or appearance of protozoans in sexual or asexual reduplication. In addition, it can successfully describe the development of the universe (small exceed of matter above antimatter at the big bang), or the increase of structures (and systems) with increasing time (development of intelligent systems). The three dimensional space possesses the lowest number of mandatory dimensions to implement such a system.

Construction, database integration, and application of an Oenothera EST library.

PubMed

Mrácek, Jaroslav; Greiner, Stephan; Cho, Won Kyong; Rauwolf, Uwe; Braun, Martha; Umate, Pavan; Altstätter, Johannes; Stoppel, Rhea; Mlcochová, Lada; Silber, Martina V; Volz, Stefanie M; White, Sarah; Selmeier, Renate; Rudd, Stephen; Herrmann, Reinhold G; Meurer, Jörg

2006-09-01

Coevolution of cellular genetic compartments is a fundamental aspect in eukaryotic genome evolution that becomes apparent in serious developmental disturbances after interspecific organelle exchanges. The genus Oenothera represents a unique, at present the only available, resource to study the role of the compartmentalized plant genome in diversification of populations and speciation processes. An integrated approach involving cDNA cloning, EST sequencing, and bioinformatic data mining was chosen using Oenothera elata with the genetic constitution nuclear genome AA with plastome type I. The Gene Ontology system grouped 1621 unique gene products into 17 different functional categories. Application of arrays generated from a selected fraction of ESTs revealed significantly differing expression profiles among closely related Oenothera species possessing the potential to generate fertile and incompatible plastid/nuclear hybrids (hybrid bleaching). Furthermore, the EST library provides a valuable source of PCR-based polymorphic molecular markers that are instrumental for genotyping and molecular mapping approaches.

Pharmacokinetic and pharmacodynamic considerations for the next generation protein therapeutics.

PubMed

Shah, Dhaval K

2015-10-01

Increasingly sophisticated protein engineering efforts have been undertaken lately to generate protein therapeutics with desired properties. This has resulted in the discovery of the next generation of protein therapeutics, which include: engineered antibodies, immunoconjugates, bi/multi-specific proteins, antibody mimetic novel scaffolds, and engineered ligands/receptors. These novel protein therapeutics possess unique physicochemical properties and act via a unique mechanism-of-action, which collectively makes their pharmacokinetics (PK) and pharmacodynamics (PD) different than other established biological molecules. Consequently, in order to support the discovery and development of these next generation molecules, it becomes important to understand the determinants controlling their PK/PD. This review discusses the determinants that a PK/PD scientist should consider during the design and development of next generation protein therapeutics. In addition, the role of systems PK/PD models in enabling rational development of the next generation protein therapeutics is emphasized.

Pharmacokinetic and pharmacodynamic considerations for the next generation protein therapeutics

PubMed Central

Shah, Dhaval K.

2015-01-01

Increasingly sophisticated protein engineering efforts have been undertaken lately to generate protein therapeutics with desired properties. This has resulted in the discovery of the next generation of protein therapeutics, which include: engineered antibodies, immunoconjugates, bi/multi-specific proteins, antibody mimetic novel scaffolds, and engineered ligands/receptors. These novel protein therapeutics possess unique physicochemical properties and act via a unique mechanism-of-action, which collectively makes their pharmacokinetics (PK) and pharmacodynamics (PD) different than other established biological molecules. Consequently, in order to support the discovery and development of these next generation molecules, it becomes important to understand the determinants controlling their PK/PD. This review discusses the determinants that a PK/PD scientist should consider during the design and development of next generation protein therapeutics. In addition, the role of systems PK/PD models in enabling rational development of the next generation protein therapeutics is emphasized. PMID:26373957

A pore-forming protein implements VLR-activated complement cytotoxicity in lamprey.

PubMed

Wu, Fenfang; Feng, Bo; Ren, Yong; Wu, Di; Chen, Yue; Huang, Shengfeng; Chen, Shangwu; Xu, Anlong

2017-01-01

Lamprey is a basal vertebrate with a unique adaptive immune system, which uses variable lymphocyte receptors (VLRs) for antigen recognition. Our previous study has shown that lamprey possessed a distinctive complement pathway activated by VLR. In this study, we identified a natterin family member-lamprey pore-forming protein (LPFP) with a jacalin-like lectin domain and an aerolysin-like pore-forming domain. LPFP had a high affinity with mannan and could form oligomer in the presence of mannan. LPFP could deposit on the surface of target cells, form pore-like complex resembling a wheel with hub and spokes, and mediate powerful cytotoxicity on target cells. These pore-forming proteins along with VLRs and complement molecules were essential for the specific cytotoxicity against exogenous pathogens and tumor cells. This unique cytotoxicity implemented by LPFP might emerge before or in parallel with the IgG-based classical complement lytic pathway completed by polyC9.

The Blood–Brain Barrier

PubMed Central

Daneman, Richard; Prat, Alexandre

2015-01-01

Blood vessels are critical to deliver oxygen and nutrients to all of the tissues and organs throughout the body. The blood vessels that vascularize the central nervous system (CNS) possess unique properties, termed the blood–brain barrier, which allow these vessels to tightly regulate the movement of ions, molecules, and cells between the blood and the brain. This precise control of CNS homeostasis allows for proper neuronal function and also protects the neural tissue from toxins and pathogens, and alterations of these barrier properties are an important component of pathology and progression of different neurological diseases. The physiological barrier is coordinated by a series of physical, transport, and metabolic properties possessed by the endothelial cells (ECs) that form the walls of the blood vessels, and these properties are regulated by interactions with different vascular, immune, and neural cells. Understanding how these different cell populations interact to regulate the barrier properties is essential for understanding how the brain functions during health and disease. PMID:25561720

Nanotechnology and the Treatment of HIV Infection

PubMed Central

Parboosing, Raveen; Maguire, Glenn E. M.; Govender, Patrick; Kruger, Hendrik G.

2012-01-01

Suboptimal adherence, toxicity, drug resistance and viral reservoirs make the lifelong treatment of HIV infection challenging. The emerging field of nanotechnology may play an important role in addressing these challenges by creating drugs that possess pharmacological advantages arising out of unique phenomena that occur at the “nano” scale. At these dimensions, particles have physicochemical properties that are distinct from those of bulk materials or single molecules or atoms. In this review, basic concepts and terms in nanotechnology are defined, and examples are provided of how nanopharmaceuticals such as nanocrystals, nanocapsules, nanoparticles, solid lipid nanoparticles, nanocarriers, micelles, liposomes and dendrimers have been investigated as potential anti-HIV therapies. Such drugs may, for example, be used to optimize the pharmacological characteristics of known antiretrovirals, deliver anti-HIV nucleic acids into infected cells or achieve targeted delivery of antivirals to the immune system, brain or latent reservoirs. Also, nanopharmaceuticals themselves may possess anti-HIV activity. However several hurdles remain, including toxicity, unwanted biological interactions and the difficulty and cost of large-scale synthesis of nanopharmaceuticals. PMID:22590683

The visual pigments of the West Indian manatee (Trichechus manatus).

PubMed

Newman, Lucy A; Robinson, Phyllis R

2006-10-01

Manatees are unique among the fully aquatic marine mammals in that they are herbivorous creatures, with hunting strategies restricted to grazing on sea-grasses. Since the other groups of (carnivorous) marine mammals have been found to possess various visual system adaptations to their unique visual environments, it was of interest to investigate the visual capability of the manatee. Previous work, both behavioral (Griebel & Schmid, 1996), and ultrastructural (Cohen, Tucker, & Odell, 1982; unpublished work cited by Griebel & Peichl, 2003), has suggested that manatees have the dichromatic color vision typical of diurnal mammals. This study uses molecular techniques to investigate the cone visual pigments of the manatee. The aim was to clone and sequence cone opsins from the retina, and, if possible, express and reconstitute functional visual pigments to perform spectral analysis. Both LWS and SWS cone opsins were cloned and sequenced from manatee retinae, which, upon expression and spectral analysis, had lambda(max) values of 555 and 410 nm, respectively. The expression of both the LWS and SWS cone opsin in the manatee retina is unique as both pinnipeds and cetaceans only express a cone LWS opsin.

Dynamical system with plastic self-organized velocity field as an alternative conceptual model of a cognitive system.

PubMed

Janson, Natalia B; Marsden, Christopher J

2017-12-05

It is well known that architecturally the brain is a neural network, i.e. a collection of many relatively simple units coupled flexibly. However, it has been unclear how the possession of this architecture enables higher-level cognitive functions, which are unique to the brain. Here, we consider the brain from the viewpoint of dynamical systems theory and hypothesize that the unique feature of the brain, the self-organized plasticity of its architecture, could represent the means of enabling the self-organized plasticity of its velocity vector field. We propose that, conceptually, the principle of cognition could amount to the existence of appropriate rules governing self-organization of the velocity field of a dynamical system with an appropriate account of stimuli. To support this hypothesis, we propose a simple non-neuromorphic mathematical model with a plastic self-organized velocity field, which has no prototype in physical world. This system is shown to be capable of basic cognition, which is illustrated numerically and with musical data. Our conceptual model could provide an additional insight into the working principles of the brain. Moreover, hardware implementations of plastic velocity fields self-organizing according to various rules could pave the way to creating artificial intelligence of a novel type.

A sight on protein-based nanoparticles as drug/gene delivery systems.

PubMed

Salatin, Sara; Jelvehgari, Mitra; Maleki-Dizaj, Solmaz; Adibkia, Khosro

2015-01-01

Polymeric nanomaterials have extensively been applied for the preparation of targeted and controlled release drug/gene delivery systems. However, problems involved in the formulation of synthetic polymers such as using of the toxic solvents and surfactants have limited their desirable applications. In this regard, natural biomolecules including proteins and polysaccharide are suitable alternatives due to their safety. According to literature, protein-based nanoparticles possess many advantages for drug and gene delivery such as biocompatibility, biodegradability and ability to functionalize with targeting ligands. This review provides a general sight on the application of biodegradable protein-based nanoparticles in drug/gene delivery based on their origins. Their unique physicochemical properties that help them to be formulated as pharmaceutical carriers are also discussed.

Grasping convergent evolution in syngnathids: a unique tale of tails.

PubMed

Neutens, C; Adriaens, D; Christiaens, J; De Kegel, B; Dierick, M; Boistel, R; Van Hoorebeke, L

2014-06-01

Seahorses and pipehorses both possess a prehensile tail, a unique characteristic among teleost fishes, allowing them to grasp and hold onto substrates such as sea grasses. Although studies have focused on tail grasping, the pattern of evolutionary transformations that made this possible is poorly understood. Recent phylogenetic studies show that the prehensile tail evolved independently in different syngnathid lineages, including seahorses, Haliichthys taeniophorus and several types of so-called pipehorses. This study explores the pattern that characterizes this convergent evolution towards a prehensile tail, by comparing the caudal musculoskeletal organization, as well as passive bending capacities in pipefish (representing the ancestral state), pipehorse, seahorse and H. taeniophorus. To study the complex musculoskeletal morphology, histological sectioning, μCT-scanning and phase contrast synchrotron scanning were combined with virtual 3D-reconstructions. Results suggest that the independent evolution towards tail grasping in syngnathids reflects at least two quite different strategies in which the ancestral condition of a heavy plated and rigid system became modified into a highly flexible one. Intermediate skeletal morphologies (between the ancestral condition and seahorses) could be found in the pygmy pipehorses and H. taeniophorus, which are phylogenetically closely affiliated with seahorses. This study suggests that the characteristic parallel myoseptal organization as already described in seahorse (compared with a conical organization in pipefish and pipehorse) may not be a necessity for grasping, but represents an apomorphy for seahorses, as this pattern is not found in other syngnathid species possessing a prehensile tail. One could suggest that the functionality of grasping evolved before the specialized, parallel myoseptal organization seen in seahorses. However, as the grasping system in pipehorses is a totally different one, this cannot be concluded from this study. © 2014 Anatomical Society.

Grasping convergent evolution in syngnathids: a unique tale of tails

PubMed Central

Neutens, C; Adriaens, D; Christiaens, J; De Kegel, B; Dierick, M; Boistel, R; Van Hoorebeke, L

2014-01-01

Seahorses and pipehorses both possess a prehensile tail, a unique characteristic among teleost fishes, allowing them to grasp and hold onto substrates such as sea grasses. Although studies have focused on tail grasping, the pattern of evolutionary transformations that made this possible is poorly understood. Recent phylogenetic studies show that the prehensile tail evolved independently in different syngnathid lineages, including seahorses, Haliichthys taeniophorus and several types of so-called pipehorses. This study explores the pattern that characterizes this convergent evolution towards a prehensile tail, by comparing the caudal musculoskeletal organization, as well as passive bending capacities in pipefish (representing the ancestral state), pipehorse, seahorse and H. taeniophorus. To study the complex musculoskeletal morphology, histological sectioning, μCT-scanning and phase contrast synchrotron scanning were combined with virtual 3D-reconstructions. Results suggest that the independent evolution towards tail grasping in syngnathids reflects at least two quite different strategies in which the ancestral condition of a heavy plated and rigid system became modified into a highly flexible one. Intermediate skeletal morphologies (between the ancestral condition and seahorses) could be found in the pygmy pipehorses and H. taeniophorus, which are phylogenetically closely affiliated with seahorses. This study suggests that the characteristic parallel myoseptal organization as already described in seahorse (compared with a conical organization in pipefish and pipehorse) may not be a necessity for grasping, but represents an apomorphy for seahorses, as this pattern is not found in other syngnathid species possessing a prehensile tail. One could suggest that the functionality of grasping evolved before the specialized, parallel myoseptal organization seen in seahorses. However, as the grasping system in pipehorses is a totally different one, this cannot be concluded from this study. PMID:24697519

Nanostructured core-shell electrode materials for electrochemical capacitors

NASA Astrophysics Data System (ADS)

Jiang, Long-bo; Yuan, Xing-zhong; Liang, Jie; Zhang, Jin; Wang, Hou; Zeng, Guang-ming

2016-11-01

Core-shell nanostructure represents a unique system for applications in electrochemical energy storage devices. Owing to the unique characteristics featuring high power delivery and long-term cycling stability, electrochemical capacitors (ECs) have emerged as one of the most attractive electrochemical storage systems since they can complement or even replace batteries in the energy storage field, especially when high power delivery or uptake is needed. This review aims to summarize recent progress on core-shell nanostructures for advanced supercapacitor applications in view of their hierarchical architecture which not only create the desired hierarchical porous channels, but also possess higher electrical conductivity and better structural mechanical stability. The core-shell nanostructures include carbon/carbon, carbon/metal oxide, carbon/conducting polymer, metal oxide/metal oxide, metal oxide/conducting polymer, conducting polymer/conducting polymer, and even more complex ternary core-shell nanoparticles. The preparation strategies, electrochemical performances, and structural stabilities of core-shell materials for ECs are summarized. The relationship between core-shell nanostructure and electrochemical performance is discussed in detail. In addition, the challenges and new trends in core-shell nanomaterials development have also been proposed.

The vascular morphology and in vivo muscle temperatures of thresher sharks (Alopiidae).

PubMed

Patterson, James C; Sepulveda, Chugey A; Bernal, Diego

2011-11-01

The thresher sharks comprise a single family (Alopiidae) of pelagic sharks most easily recognized by the elongate dorsal lobe of their caudal fin. Despite morphological similarities among the alopiids, the common thresher (Alopias vulpinus) is unique in that its red, aerobic myotomal muscle (RM) is medially positioned (i.e., closer to the vertebrae), its systemic blood is supplied through a lateral circulation which give rise to counter-current heat exchanging retia, and it is capable of regional RM endothermy. Despite this information, it remains unknown if the other two alopiid species (bigeye thresher, Alopias superciliosus and pelagic thresher, Alopias pelagicus) also possess some or all of the characteristics related to regional RM endothermy. Thus, this study aimed to 1) document the presence of vascular specializations necessary for heat retention and RM endothermy and 2) measure the in vivo muscle temperatures of all three alopiid species. Laboratory dissections of the thresher species showed that only A. vulpinus possesses the lateral branching of the dorsal aorta giving rise to a lateral subcutaneous circulation and retial system, and that RM temperatures are elevated relative to ambient temperature. By contrast, both A. pelagicus and A. superciliosus have a similar systemic blood circulation pathway, in which the dorsal aorta and postcardinal vein form the basis for the central circulation and in vivo RM temperature measurements closely matched those of the ambient temperature at which the sharks were captured. Collectively, the vascular anatomy and in vivo temperature data suggest that only one species of thresher shark (A. vulpinus) possesses the requisite vascular specializations (i.e., lateral subcutaneous vessels and retia mirabilia) that facilitate RM endothermy. Copyright © 2011 Wiley-Liss, Inc.

Differential Distributions of Synechococcus Subgroups Across the California Current System

PubMed Central

Paerl, Ryan W.; Johnson, Kenneth S.; Welsh, Rory M.; Worden, Alexandra Z.; Chavez, Francisco P.; Zehr, Jonathan P.

2011-01-01

Synechococcus is an abundant marine cyanobacterial genus composed of different populations that vary physiologically. Synechococcus narB gene sequences (encoding for nitrate reductase in cyanobacteria) obtained previously from isolates and the environment (e.g., North Pacific Gyre Station ALOHA, Hawaii or Monterey Bay, CA, USA) were used to develop quantitative PCR (qPCR) assays. These qPCR assays were used to quantify populations from specific narB phylogenetic clades across the California Current System (CCS), a region composed of dynamic zones between a coastal-upwelling zone and the oligotrophic Pacific Ocean. Targeted populations (narB subgroups) had different biogeographic patterns across the CCS, which appear to be driven by environmental conditions. Subgroups C_C1, D_C1, and D_C2 were abundant in coastal-upwelling to coastal-transition zone waters with relatively high to intermediate ammonium, nitrate, and chl. a concentrations. Subgroups A_C1 and F_C1 were most abundant in coastal-transition zone waters with intermediate nutrient concentrations. E_O1 and G_O1 were most abundant at different depths of oligotrophic open-ocean waters (either in the upper mixed layer or just below). E_O1, A_C1, and F_C1 distributions differed from other narB subgroups and likely possess unique ecologies enabling them to be most abundant in waters between coastal and open-ocean waters. Different CCS zones possessed distinct Synechococcus communities. Core California current water possessed low numbers of narB subgroups relative to counted Synechococcus cells, and coastal-transition waters contained high abundances of Synechococcus cells and total number of narB subgroups. The presented biogeographic data provides insight on the distributions and ecologies of Synechococcus present in an eastern boundary current system. PMID:21833315

Development of the pseudothumb in frogs

PubMed Central

Tokita, Masayoshi; Iwai, Noriko

2010-01-01

Frogs have highly conserved hand and foot morphology, possessing four fingers and five toes. As an exception, two Japanese ranid frog species, the Otton frog Babina subaspera and the dagger frog Babina holsti, possess a unique thumb-like structure (the pseudothumb) in the forelimb, giving an appearance of a total of five fingers on the hand. To obtain insights into the developmental mechanisms that generate this novel character, we investigated the hand morphogenesis of the Otton frog. The unique morphological pattern of the pseudothumb was already established in juveniles. Surprisingly, the bud-like structure, which is similar to the area of inductive activity (e.g. feather buds in birds and the carapacial ridge in turtles), was detected over the site where the future prepollex develops in larvae. By contrast, this bud-like structure was not found in larvae of other ranid species. We discuss possible scenarios that would favour the evolution of this very unusual trait in frogs. PMID:20147308

Amorphous photonic crystals with only short-range order.

PubMed

Shi, Lei; Zhang, Yafeng; Dong, Biqin; Zhan, Tianrong; Liu, Xiaohan; Zi, Jian

2013-10-04

Distinct from conventional photonic crystals with both short- and long-range order, amorphous photonic crystals that possess only short-range order show interesting optical responses owing to their unique structural features. Amorphous photonic crystals exhibit unique light scattering and transport, which lead to a variety of interesting phenomena such as isotropic photonic bandgaps or pseudogaps, noniridescent structural colors, and light localization. Recent experimental and theoretical advances in the study of amorphous photonic crystals are summarized, focusing on their unique optical properties, artificial fabrication, bionspiration, and potential applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phylogeny of Fish-Infecting Calyptospora species (Apicomplexa: Eimeriorina)

EPA Science Inventory

There are numerous species of apicomplexans that infect poikilothermic vertebrates such as fishes, and possess unique morphological features that provide insight into the evolution of this important phylum of parasites. Here the relationship of the fish-infecting Calyptospora spe...

A shark antibody heavy chain encoded by a nonsomatically rearranged VDJ is preferentially expressed in early development and is convergent with mammalian IgG

PubMed Central

Rumfelt, Lynn L.; Avila, David; Diaz, Marilyn; Bartl, Simona; McKinney, E. Churchill; Flajnik, Martin F.

2001-01-01

In most vertebrate embryos and neonates studied to date unique antigen receptors (antibodies and T cell receptors) are expressed that possess a limited immune repertoire. We have isolated a subclass of IgM, IgM1gj, from the nurse shark Ginglymostoma cirratum that is preferentially expressed in neonates. The variable (V) region gene encoding the heavy (H) chain underwent V-D-J rearrangement in germ cells (“germline-joined”). Such H chain V genes were discovered over 10 years ago in sharks but until now were not shown to be expressed at appreciable levels; we find expression of H1gj in primary and secondary lymphoid tissues early in life, but in adults only in primary lymphoid tissue, which is identified in this work as the epigonal organ. H1gj chain associates covalently with light (L) chains and is most similar in sequence to IgM H chains, but like mammalian IgG has three rather than the four IgM constant domains; deletion of the ancestral IgM C2 domain thus defines both IgG and IgM1gj. Because sharks are the members of the oldest vertebrate class known to possess antibodies, unique or specialized antibodies expressed early in ontogeny in sharks and other vertebrates were likely present at the inception of the adaptive immune system. PMID:11172027

Inviscid and viscous flow modelling of complex aircraft configurations using the CFD simulation system sauna

NASA Astrophysics Data System (ADS)

Peace, Andrew J.; May, Nicholas E.; Pocock, Mark F.; Shaw, Jonathon A.

1994-04-01

This paper is concerned with the flow modelling capabilities of an advanced CFD simulation system known by the acronym SAUNA. This system is aimed primarily at complex aircraft configurations and possesses a unique grid generation strategy in its use of block-structured, unstructured or hybrid grids, depending on the geometric complexity of the addressed configuration. The main focus of the paper is in demonstrating the recently developed multi-grid, block-structured grid, viscous flow capability of SAUNA, through its evaluation on a number of configurations. Inviscid predictions are also presented, both as a means of interpreting the viscous results and with a view to showing more completely the capabilities of SAUNA. It is shown that accuracy and flexibility are combined in an efficient manner, thus demonstrating the value of SAUNA in aerodynamic design.

Interprofessional collaboration: if not now, when?

PubMed

Fried, Jackie

2013-01-01

Interprofessional collaboration (IPC) is a driving force behind state-of-the art health care delivery. Health care experts, governmental bodies, health professions organizations and academicians support the need for collaborative models. Dental hygienists possess unique qualities that can enhance a collaborative team. As preventive therapists, health educators and holistic providers, they are positioned to contribute richly and meaningfully to team models. Health care reform, overwhelming oral health needs and growing associations between oral and systemic wellness add to the dental hygienist's relevance in collaborative arrangements. Dental hygiene clinical and educational models that speak to collaboration are operational in many U.S. states and the future bodes well for their continued growth.

[Methods of quantitative proteomics].

PubMed

Kopylov, A T; Zgoda, V G

2007-01-01

In modern science proteomic analysis is inseparable from other fields of systemic biology. Possessing huge resources quantitative proteomics operates colossal information on molecular mechanisms of life. Advances in proteomics help researchers to solve complex problems of cell signaling, posttranslational modification, structure and functional homology of proteins, molecular diagnostics etc. More than 40 various methods have been developed in proteomics for quantitative analysis of proteins. Although each method is unique and has certain advantages and disadvantages all these use various isotope labels (tags). In this review we will consider the most popular and effective methods employing both chemical modifications of proteins and also metabolic and enzymatic methods of isotope labeling.

Dimacrolide Sesquiterpene Pyridine Alkaloids from the Stems of Tripterygium regelii.

PubMed

Fan, Dongsheng; Zhu, Guo-Yuan; Li, Ting; Jiang, Zhi-Hong; Bai, Li-Ping

2016-08-29

Two new dimacrolide sesquiterpene pyridine alkaloids (DMSPAs), dimacroregelines A (1) and B (2), were isolated from the stems of Tripterygium regelii. The structures of both compounds were characterized by extensive 1D and 2D NMR spectroscopic analyses, as well as HRESIMS data. Compounds 1 and 2 are two rare DMSPAs possessing unique 2-(3'-carboxybutyl)-3-furanoic acid units forming the second macrocyclic ring, representing the first example of DMSPAs bearing an extra furan ring in their second macrocyclic ring system. Compound 2 showed inhibitory effects on the proliferation of human rheumatoid arthritis synovial fibroblast cell (MH7A) at a concentration of 20 μM.

A new ultrasonic real-time scanner featuring a servo-controlled transducer displaying a sector image.

PubMed

Skolnick, M L; Matzuk, T

1978-08-01

This paper describes a new real-time servo-controlled sector scanner that produces high-resolution images similar to phased-array systems, but possesses the simplicity of design and low cost best achievable in a mechanical sector scanner. Its unique feature is the transducer head which contains a single moving part--the transducer. Frame rates vary from 0 to 30 degrees and the sector angle from 0 to 60 degrees. Abdominal applications include: differentiation of vascular structures, detection of small masses, imaging of diagonally oriented organs. Survey scanning, and demonstration of regions difficult to image with contact scanners. Cardiac uses are also described.

Rhodomollanol A, a Highly Oxygenated Diterpenoid with a 5/7/5/5 Tetracyclic Carbon Skeleton from the Leaves of Rhododendron molle.

PubMed

Zhou, Junfei; Zhan, Guanqun; Zhang, Hanqi; Zhang, Qihua; Li, Ying; Xue, Yongbo; Yao, Guangmin

2017-07-21

A novel diterpenoid with an unprecedented carbon skeleton, rhodomollanol A (1), and a new grayanane diterpenoid, rhodomollein XXXI (2), were isolated from the leaves of Rhododendron molle. Their structures were elucidated using comprehensive spectroscopic methods and single-crystal X-ray diffraction. Compound 1 possesses a unique cis/trans/trans/cis/cis-fused 3/5/7/5/5/5 hexacyclic ring system featuring a rare 7-oxabicyclo[4.2.1]nonane core decorated with three cyclopentane units. The plausible biosynthetic pathway for 1 was proposed. Compound 1 exhibited moderate PTP1B inhibitory activity.

Consciousness: a unique way of processing information.

PubMed

Marchetti, Giorgio

2018-02-08

In this article, I argue that consciousness is a unique way of processing information, in that: it produces information, rather than purely transmitting it; the information it produces is meaningful for us; the meaning it has is always individuated. This uniqueness allows us to process information on the basis of our personal needs and ever-changing interactions with the environment, and consequently to act autonomously. Three main basic cognitive processes contribute to realize this unique way of information processing: the self, attention and working memory. The self, which is primarily expressed via the central and peripheral nervous systems, maps our body, the environment, and our relations with the environment. It is the primary means by which the complexity inherent to our composite structure is reduced into the "single voice" of a unique individual. It provides a reference system that (albeit evolving) is sufficiently stable to define the variations that will be used as the raw material for the construction of conscious information. Attention allows for the selection of those variations in the state of the self that are most relevant in the given situation. Attention originates and is deployed from a single locus inside our body, which represents the center of the self, around which all our conscious experiences are organized. Whatever is focused by attention appears in our consciousness as possessing a spatial quality defined by this center and the direction toward which attention is focused. In addition, attention determines two other features of conscious experience: periodicity and phenomenal quality. Self and attention are necessary but not sufficient for conscious information to be produced. Complex forms of conscious experiences, such as the various modes of givenness of conscious experience and the stream of consciousness, need a working memory mechanism to assemble the basic pieces of information selected by attention.

Commissioning of a new photon detection system for charge radii measurements of neutron-deficient Ca

NASA Astrophysics Data System (ADS)

Watkins, J.; Garand, D.; Miller, A. J.; Minamisono, K.; Everett, N.; Powel, R. C.; Maaß, B.; Nörtershäuser, W.; Kalman, C.; Lantis, J.; Kujawa, C.; Mantica, P.

2017-09-01

Calcium is unique for its possession of two stable isotopes of ``doubly magic'' nuclei at proton and neutron numbers (Z , N) = (20 , 20) and (20 , 28) . Recent charge radii measurements of neutron-rich calcium isotopes yielded an upward trend beyond current theoretical predictions. At the BECOLA facility at NSCL/MSU, Ca charge radii measurements will be extended to the neutron-deficient regime using collinear laser spectroscopy. A new photon detection system with an ellipsoidal reflector and a compound parabolic concentrator has been commissioned for the experiment. The system increases the signal-to-noise ratio by reducing background, which is critical for the low production rates of the Ca experiment. Details of the system and results of the characterization tests will be discussed. Work supported in part by NSF Grant PHY-15-65546, U.S. DOE Grant DE-NA0002924 and by the Deutsche Forschungsgemeinschaft Grant SFB 1245.

THE PUZZLING MUTUAL ORBIT OF THE BINARY TROJAN ASTEROID (624) HEKTOR

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

Marchis, F.; Cuk, M.; Durech, J.

Asteroids with satellites are natural laboratories to constrain the formation and evolution of our solar system. The binary Trojan asteroid (624) Hektor is the only known Trojan asteroid to possess a small satellite. Based on W. M. Keck adaptive optics observations, we found a unique and stable orbital solution, which is uncommon in comparison to the orbits of other large multiple asteroid systems studied so far. From lightcurve observations recorded since 1957, we showed that because the large Req = 125 km primary may be made of two joint lobes, the moon could be ejecta of the low-velocity encounter, which formedmore » the system. The inferred density of Hektor's system is comparable to the L5 Trojan doublet (617) Patroclus but due to their difference in physical properties and in reflectance spectra, both captured Trojan asteroids could have a different composition and origin.« less

Phoretomorph: a new phoretic phase unique to the pyemotidae (Acarina: Tarsonemoidea)

Treesearch

John C. Moser; E.A. Cross

1975-01-01

The poretomorph, representing a new type of phoresy for the Acarina, is a female specialized for riding insects. Certain pyemotid species possess both phoretomorphic and non-phoretomorphic females, but others are monomorphic and ahve one or the other.

32 CFR 104.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... UNIFORMED SERVICES § 104.3 Definitions. Critical mission. An operational mission that requires the skills or... incumbent possesses unique knowledge, extensive experience, and specialty skill training to successfully... requirement in which the incumbent must gain the necessary experience to qualify for key senior leadership...

The Unique Mitochondrial Genetics of Cucumber

USDA-ARS?s Scientific Manuscript database

Plant cells typically contain two organelles, plastids and mitochondria. For the vast majority of plants, both of these organelles are maternally transmitted. Cucumber and melon are exceptions to this rule because the mitochondria are paternally transmitted. These two plants also possess mitochon...

Controlling tissue microenvironments: biomimetics, transport phenomena, and reacting systems.

PubMed

Fisher, Robert J; Peattie, Robert A

2007-01-01

The reconstruction of tissues ex vivo and production of cells capable of maintaining a stable performance for extended time periods in sufficient quantity for synthetic or therapeutic purposes are primary objectives of tissue engineering. The ability to characterize and manipulate the cellular microenvironment is critical for successful implementation of such cell-based bioengineered systems. As a result, knowledge of fundamental biomimetics, transport phenomena, and reaction engineering concepts is essential to system design and development. Once the requirements of a specific tissue microenvironment are understood, the biomimetic system specifications can be identified and a design implemented. Utilization of novel membrane systems that are engineered to possess unique transport and reactive features is one successful approach presented here. The limited availability of tissue or cells for these systems dictates the need for microscale reactors. A capstone illustration based on cellular therapy for type 1 diabetes mellitus via encapsulation techniques is presented as a representative example of this approach, to stress the importance of integrated systems.

Management of the aging upper eyelid in the asian patient.

PubMed

Karam, Amir M; Lam, Samuel M

2010-08-01

Successful management of the aging upper eyelid region in the Asian patient requires a unique skill set and clinical experience. The surgeon must exhibit a thorough understanding of the unique anatomy of the Asian eyelid and its variations and of the cultural expectations of the patient and must possess a unique set of surgical skills such as de novo creation of the supratarsal crease as well as complementary procedures such as fat transfer used for volume augmentation of the periorbital region. The modern approach outlined here summarizes the key elements necessary to restore the youthful appearance of the upper eyelid region in a natural and ethnically consistent fashion.

Engineering refinements to overcome default nuclide regulatory constraints

NASA Astrophysics Data System (ADS)

Finn, R.; Capitelli, P.; Sheh, Y.; Lom, C.; Graham, M.; Germain, J. St.

2005-12-01

The "classical" positron emitting radionuclides include oxygen-15, nitrogen-13 and carbon-11 which possess unique properties for medical imaging. They are radionuclides of the fundamental elements of biological matter. They each possess short half-lives which allow their use in designed radiotracers for clinical investigations with minimal risk and they are readily able to be produced in sufficient activities by low energy nuclear reactions. At present several accelerator manufacturers offer production packages for these radionuclides emphasizing targetry with consideration of the cyclotron extracted energies for nuclide production and on-line chemistry systems for the continuous production of specific precursors or radiotracers. Following the installation and acceptance of the MSKCC TR 19/9 Cyclotron, our experience with the procured chemistry module for the preparation of oxygen-15 labeled water has forced us to examine the design and the operation of the synthetic unit with a view toward the state of New York's regulations addressing the environmental pollution from radioactive materials. The chemistry module was refined with subtle modifications to the chemistry procedure/unit and our experience with the unit is presented as an example of our approach to insure regulatory compliance.

Occurrence and structure of epipharyngeal pouches in bears (Ursidae)

PubMed Central

WEISSENGRUBER, G. E.; FORSTENPOINTNER, G.; KÜBBER-HEISS, A.; RIEDELBERGER, K.; SCHWAMMER, H.; GANZBERGER, K.

2001-01-01

The infrequent mention of epipharyngeal pouches occurring in some species of bears indicates the scarcity of morphological and functional knowledge about these structures. In order to provide precise morphological data on the structure of these remarkable formations and to verify their taxonomic utility, the pharyngeal regions of 1 spectacled bear and 3 brown bears were examined. All these individuals possessed epipharyngeal pouches, which are tubular, blind-ending outpouchings of the caudodorsal pharyngeal wall equipped with respiratory epithelium and a thick layer of elastic fibres. While the spectacled bear and Ursus arctos syriacus possessed a single pouch on the caudodorsal wall of the nasopharynx, in Ursus arctos and Ursus arctos beringianus 2 unequally sized pouches were present. Two additional sacs of smaller size, representing outpouchings of the lateral pharyngeal wall, occurred in the spectacled bear. These findings prove epipharyngeal pouches to be constant and unique morphological features of the family Ursidae, the anatomical features suggesting involvement in the respiratory system most probably in important aspects of ursid phonation. This is the first description of epipharyngeal pouches in the spectacled bear. PMID:11322723

A distinct sortase SrtB anchors and processes a streptococcal adhesin AbpA with a novel structural property

PubMed Central

Liang, Xiaobo; Liu, Bing; Zhu, Fan; Scannapieco, Frank A.; Haase, Elaine M.; Matthews, Steve; Wu, Hui

2016-01-01

Surface display of proteins by sortases in Gram-positive bacteria is crucial for bacterial fitness and virulence. We found a unique gene locus encoding an amylase-binding adhesin AbpA and a sortase B in oral streptococci. AbpA possesses a new distinct C-terminal cell wall sorting signal. We demonstrated that this C-terminal motif is required for anchoring AbpA to cell wall. In vitro and in vivo studies revealed that SrtB has dual functions, anchoring AbpA to the cell wall and processing AbpA into a ladder profile. Solution structure of AbpA determined by NMR reveals a novel structure comprising a small globular α/β domain and an extended coiled-coil heliacal domain. Structural and biochemical studies identified key residues that are crucial for amylase binding. Taken together, our studies document a unique sortase/adhesion substrate system in streptococci adapted to the oral environment rich in salivary amylase. PMID:27492581

The future of quantum dots in drug discovery.

PubMed

Lin, Guimiao; Yin, Feng; Yong, Ken-Tye

2014-09-01

The rapid development of drug discovery today is inseparable from the interaction of advanced particle technologies and new drug synthesis protocols. Quantum dots (QDs) are regarded as a unique class of fluorescent labels, with unique optical properties such as high brightness and long-term colloidal and optical stability; these are suitable for optical imaging, drug delivery and optical tracking, fluorescence immunoassay and other medicinal applications. More importantly, QD possesses a rich surface chemistry property that is useful for incorporating various drug molecules, targeting ligands, and additional contrast agents (e.g., MRI, PET, etc.) onto the nanoparticle surface for achieving targeted and traceable drug delivery therapy at both cellular and systemic levels. In recent times, the advancement of QD technology has promoted the use of functionalized nanocrystals for in vivo applications. Such research is paving the way for drug discovery using various bioconjugated QD formulations. In this editorial, the authors highlight the current research progress and future applications of QDs in drug discovery.

Comparative Genomics of Acetobacterpasteurianus Ab3, an Acetic Acid Producing Strain Isolated from Chinese Traditional Rice Vinegar Meiguichu.

PubMed

Xia, Kai; Li, Yudong; Sun, Jing; Liang, Xinle

2016-01-01

Acetobacter pasteurianus, an acetic acid resistant bacterium belonging to alpha-proteobacteria, has been widely used to produce vinegar in the food industry. To understand the mechanism of its high tolerance to acetic acid and robust ability of oxidizing ethanol to acetic acid (> 12%, w/v), we described the 3.1 Mb complete genome sequence (including 0.28 M plasmid sequence) with a G+C content of 52.4% of A. pasteurianus Ab3, which was isolated from the traditional Chinese rice vinegar (Meiguichu) fermentation process. Automatic annotation of the complete genome revealed 2,786 protein-coding genes and 73 RNA genes. The comparative genome analysis among A. pasteurianus strains revealed that A. pasteurianus Ab3 possesses many unique genes potentially involved in acetic acid resistance mechanisms. In particular, two-component systems or toxin-antitoxin systems may be the signal pathway and modulatory network in A. pasteurianus to cope with acid stress. In addition, the large numbers of unique transport systems may also be related to its acid resistance capacity and cell fitness. Our results provide new clues to understanding the underlying mechanisms of acetic acid resistance in Acetobacter species and guiding industrial strain breeding for vinegar fermentation processes.

Comparative Genomics of Acetobacterpasteurianus Ab3, an Acetic Acid Producing Strain Isolated from Chinese Traditional Rice Vinegar Meiguichu

PubMed Central

Xia, Kai; Li, Yudong; Sun, Jing; Liang, Xinle

2016-01-01

Acetobacter pasteurianus, an acetic acid resistant bacterium belonging to alpha-proteobacteria, has been widely used to produce vinegar in the food industry. To understand the mechanism of its high tolerance to acetic acid and robust ability of oxidizing ethanol to acetic acid (> 12%, w/v), we described the 3.1 Mb complete genome sequence (including 0.28 M plasmid sequence) with a G+C content of 52.4% of A. pasteurianus Ab3, which was isolated from the traditional Chinese rice vinegar (Meiguichu) fermentation process. Automatic annotation of the complete genome revealed 2,786 protein-coding genes and 73 RNA genes. The comparative genome analysis among A. pasteurianus strains revealed that A. pasteurianus Ab3 possesses many unique genes potentially involved in acetic acid resistance mechanisms. In particular, two-component systems or toxin-antitoxin systems may be the signal pathway and modulatory network in A. pasteurianus to cope with acid stress. In addition, the large numbers of unique transport systems may also be related to its acid resistance capacity and cell fitness. Our results provide new clues to understanding the underlying mechanisms of acetic acid resistance in Acetobacter species and guiding industrial strain breeding for vinegar fermentation processes. PMID:27611790

Molecular Basis of Infrared Detection by Snakes

PubMed Central

Gracheva, Elena O.; Ingolia, Nicolas T.; Kelly, Yvonne M.; Cordero-Morales, Julio F.; Hollopeter, Gunther; Chesler, Alexander T.; Sánchez, Elda E.; Perez, John C.; Weissman, Jonathan S.; Julius, David

2010-01-01

Snakes possess a unique sensory system for detecting infrared radiation, enabling them to generate a ‘thermal image’ of predators or prey. Infrared signals are initially received by the pit organ, a highly specialized facial structure that is innervated by nerve fibers of the somatosensory system. How this organ detects and transduces infrared signals into nerve impulses is not known. Here we use an unbiased transcriptional profiling approach to identify TRPA1 channels as infrared receptors on sensory nerve fibers that innervate the pit organ. TRPA1 orthologues from pit bearing snakes (vipers, pythons, and boas) are the most heat sensitive vertebrate ion channels thus far identified, consistent with their role as primary transducers of infrared stimuli. Thus, snakes detect infrared signals through a mechanism involving radiant heating of the pit organ, rather than photochemical transduction. These findings illustrate the broad evolutionary tuning of TRP channels as thermosensors in the vertebrate nervous system. PMID:20228791

Making Peace Pay: Post-Conflict Economic and Infrastructure Development in Kosovo and Iraq

DTIC Science & Technology

probability that a post-conflict state will return to war. Additionally, consecutive presidential administrations and joint doctrine have declared...and Iraqi Freedom as historical case studies to demonstrate that the armed forces possess unique advantages, to include physical presence and

Tools for Assessing Ecological Nanomaterial Exposures

EPA Science Inventory

Manufactured nanomaterials (MNs) are commonly defined as being commercial products with at least one dimension in the size range of 1 nm to 100 nm that also possess unique properties as the result of their size. Anecdotal evidence suggests that at least 600 MN products a...

Understanding Student Motivation

ERIC Educational Resources Information Center

Seifert, Timothy

2004-01-01

Contemporary theories of academic motivation seek to explain students' behaviours in academic settings. While each theory seems to possess its own constructs and unique explanations, these theories are actually closely tied together. In this theoretical study of motivation, several theories of motivation were described and an underlying theme of…

Draft genome sequence of marine alphaproteobacterial strain HIMB11, the first cultivated representative of a unique lineage within the Roseobacter clade possessing an unusually small genome

PubMed Central

Durham, Bryndan P.; Grote, Jana; Whittaker, Kerry A.; Bender, Sara J.; Luo, Haiwei; Grim, Sharon L.; Brown, Julia M.; Casey, John R.; Dron, Antony; Florez-Leiva, Lennin; Krupke, Andreas; Luria, Catherine M.; Mine, Aric H.; Nigro, Olivia D.; Pather, Santhiska; Talarmin, Agathe; Wear, Emma K.; Weber, Thomas S.; Wilson, Jesse M.; Church, Matthew J.; DeLong, Edward F.; Karl, David M.; Steward, Grieg F.; Eppley, John M.; Kyrpides, Nikos C.; Schuster, Stephan; Rappé, Michael S.

2014-01-01

Strain HIMB11 is a planktonic marine bacterium isolated from coastal seawater in Kaneohe Bay, Oahu, Hawaii belonging to the ubiquitous and versatile Roseobacter clade of the alphaproteobacterial family Rhodobacteraceae. Here we describe the preliminary characteristics of strain HIMB11, including annotation of the draft genome sequence and comparative genomic analysis with other members of the Roseobacter lineage. The 3,098,747 bp draft genome is arranged in 34 contigs and contains 3,183 protein-coding genes and 54 RNA genes. Phylogenomic and 16S rRNA gene analyses indicate that HIMB11 represents a unique sublineage within the Roseobacter clade. Comparison with other publicly available genome sequences from members of the Roseobacter lineage reveals that strain HIMB11 has the genomic potential to utilize a wide variety of energy sources (e.g. organic matter, reduced inorganic sulfur, light, carbon monoxide), while possessing a reduced number of substrate transporters. PMID:25197450

Draft genome sequence of marine alphaproteobacterial strain HIMB11, the first cultivated representative of a unique lineage within the Roseobacter clade possessing an unusually small genome.

PubMed

Durham, Bryndan P; Grote, Jana; Whittaker, Kerry A; Bender, Sara J; Luo, Haiwei; Grim, Sharon L; Brown, Julia M; Casey, John R; Dron, Antony; Florez-Leiva, Lennin; Krupke, Andreas; Luria, Catherine M; Mine, Aric H; Nigro, Olivia D; Pather, Santhiska; Talarmin, Agathe; Wear, Emma K; Weber, Thomas S; Wilson, Jesse M; Church, Matthew J; DeLong, Edward F; Karl, David M; Steward, Grieg F; Eppley, John M; Kyrpides, Nikos C; Schuster, Stephan; Rappé, Michael S

2014-06-15

Strain HIMB11 is a planktonic marine bacterium isolated from coastal seawater in Kaneohe Bay, Oahu, Hawaii belonging to the ubiquitous and versatile Roseobacter clade of the alphaproteobacterial family Rhodobacteraceae. Here we describe the preliminary characteristics of strain HIMB11, including annotation of the draft genome sequence and comparative genomic analysis with other members of the Roseobacter lineage. The 3,098,747 bp draft genome is arranged in 34 contigs and contains 3,183 protein-coding genes and 54 RNA genes. Phylogenomic and 16S rRNA gene analyses indicate that HIMB11 represents a unique sublineage within the Roseobacter clade. Comparison with other publicly available genome sequences from members of the Roseobacter lineage reveals that strain HIMB11 has the genomic potential to utilize a wide variety of energy sources (e.g. organic matter, reduced inorganic sulfur, light, carbon monoxide), while possessing a reduced number of substrate transporters.

Chlorhexidine possesses unique cytotoxic actions in rat thymic lymphocytes: Its relation with electrochemical property of membranes.

PubMed

Nonami, Kayo; Saitoh, Shohei; Nishimura-Danjobara, Yumiko; Ishida, Shiro; Oyama, Yasuo

2016-12-01

Chlorhexidine (CHX) is an antibacterial agent used in various types of pharmaceutical products. Therefore, CHX is easily found around us. Owing to its positive charge, the electrochemical property of cell membranes was assumed to be a key point of cytotoxic action of CHX. Depolarization of membranes attenuated the cytotoxic action of CHX in rat thymic lymphocytes. CHX interfered with annexin V binding to membranes. Manipulations to induce exposure of phosphatidylserine on the outer membrane surface augmented the cytotoxic action of CHX, indicating that changes in the electrochemical property of membranes affected the cytotoxic action of CHX. Hence, CHX might kill cells physiologically undergoing apoptosis, resulting instead in necrotic cell death. However, the threshold CHX concentration in this in vitro study was slightly higher than blood CHX concentrations observed clinically. Therefore, these results may support the safety of CHX use although CHX possesses unique cytotoxic actions described in this study. Copyright © 2016 Elsevier B.V. All rights reserved.

Chapter 19: Catalysis by Metal Carbides and Nitrides

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

Schaidle, Joshua A; Nash, Connor P; Yung, Matthew M

Early transition metal carbides and nitrides (ETMCNs), materials in which carbon or nitrogen occupies interstitial sites within a parent metal lattice, possess unique physical and chemical properties that motivate their use as catalysts. Specifically, these materials possess multiple types of catalytic sites, including metallic, acidic, and basic sites, and as such, exhibit reactivities that differ from their parent metals. Moreover, their surfaces are dynamic under reaction conditions. This chapter reviews recent (since 2010) experimental and computational investigations into the catalytic properties of ETMCN materials for applications including biomass conversion, syngas and CO2 upgrading, petroleum and natural gas refining, and electrocatalyticmore » energy conversion, energy storage, and chemicals production, and attempts to link catalyst performance to active site identity/surface structure in order to elucidate the present level of understanding of structure-function relationships for these materials. The chapter concludes with a perspective on leveraging the unique properties of these materials to design and develop improved catalysts through a dedicated, multidisciplinary effort.« less

Growth Mechanism of a Unique Hierarchical Vaterite Structure

NASA Astrophysics Data System (ADS)

Ma, Guobin; Xu, Yifei; Wang, Mu

2013-03-01

Calcium carbonate is one of the most significant minerals in nature as well as in biogenic sources. Calcium carbonate occurs naturally in three crystalline polymorphs, i.e., calcite, aragonite, and vaterite. Although it has been attracted much research attention to understanding of the formation mechanisms of the material, the properties of the vaterite polymorph is not well known. Here we report synthesis and formation mechanism of a unique hierarchical structure of vaterite. The material is grown by a controlled diffusion method. The structure possesses a core and an outer part. The core is convex lens-like and is formed by vaterite nanocrystals that have small misorientations. The outer part is separated into six garlic clove-like segments. Each segment possesses piles of plate-like vaterite crystals, and the orientations of the plates continuously change from pile to pile. Based on real-time experimental results and the structural analysis, a growth mechanism is presented. Work supported by NSFC (Grant No. 51172104) and MOST of China (Grant No. 2101CB630705)

Boron Nitride Nanotubes for Engineering Applications

NASA Technical Reports Server (NTRS)

Hurst, Janet; Hull, David; Gorican, Daniel

2005-01-01

Boron nitride nanotubes (BNNT) are of significant interest to the scientific and technical communities for many of the same reasons that carbon nanotubes (CNT) have attracted wide attention. Both materials have potentially unique and important properties for structural and electronic applications. However of even more consequence than their similarities may be the complementary differences between carbon and boron nitride nanotubes While BNNT possess a very high modulus similar to CNT, they also possess superior chemical and thermal stability. Additionally, BNNT have more uniform electronic properties, with a uniform band gap of 5.5 eV while CNT vary from semi-conductive to highly conductive behavior. Boron nitride nanotubes have been synthesized both in the literature and at NASA Glenn Research Center, by a variety of methods such as chemical vapor deposition, arc discharge and reactive milling. Consistent large scale production of a reliable product has proven difficult. Progress in the reproducible synthesis of 1-2 gram sized batches of boron nitride nanotubes will be discussed as well as potential uses for this unique material.

Synthesis of Boron Nitride Nanotubes for Engineering Applications

NASA Technical Reports Server (NTRS)

Hurst, Janet; Hull, David; Gorican, Dan

2005-01-01

Boron Nitride nanotubes (BNNT) are of interest to the scientific and technical communities for many of the same reasons that carbon nanotubes (CNT) have attracted large amounts of attention. Both materials have potentially unique and significant properties which may have important structural and electronic applications in the future. However of even more interest than their similarities may be the differences between carbon and boron nanotubes. Whilt boron nitride nanotubes possess a very high modulus similaar to CNT, they are also more chemically and thermally inert. Additionally BNNT possess more uniform electronic properties, having a uniform band gap of approximately 5.5 eV while CNT vary from semi-conductin to conductor behavior. Boron Nitride nanotubes have been synthesized by a variety of methods such as chemical vapor deposition, arc discharge and reactive milling. Consistently producing a reliable product has proven difficult. Progress in synthesis of 1-2 gram sized batches of Boron Nitride nanotubes will be discussed as well as potential uses for this unique material.

The Steris Reliance EPS endoscope processing system: a new automated endoscope reprocessing technology.

PubMed

2007-01-01

In this Evaluation, we examine whether the Steris Reliance EPS--a flexible endoscope reprocessing system that was recently introduced to the U.S. market--offers meaningful advantages over "traditional" automated endoscope reprocessors (AERs). Most AERs on the market function similarly to one another. The Reliance EPS, however, includes some unique features that distinguish it from other AERs. For example, it incorporates a "boot" technology for loading the endoscopes into the unit without requiring a lot of endoscope-specific connectors, and it dispenses the germicide used to disinfect the endoscopes from a single-use container. This Evaluation looks at whether the unique features of this model make it a better choice than traditional AERs for reprocessing flexible endoscopes. Our study focuses on whether the Reliance EPS is any more likely to be used correctly-thereby reducing the likelihood that an endoscope will be reprocessed inadequately-and whether the unit possesses any design flaws that could lead to reprocessing failures. We detail the unit's advantages and disadvantages compared with other AERs, and we describe what current users have to say. Our conclusions will help facilities determine whether to select the Reliance EPS.

Extrinsic and intrinsic mechanisms by which mesenchymal stem cells suppress the immune system

PubMed Central

Coulson-Thomas, Vivien J.; Coulson-Thomas, Yvette M.; Gesteira, Tarsis F.; Kao, Winston W.-Y.

2016-01-01

Mesenchymal stem cells (MSCs) are a group of fibroblast-like multipotent mesenchymal stromal cells that have the ability to differentiate into osteoblasts, adipocytes, and chondrocytes. Recent studies have demonstrated that MSCs possess a unique ability to exert suppressive and regulatory effects on both adaptive and innate immunity in an autologous and allogeneic manner. A vital step in stem cell transplantation is overcoming the potential graft-versus-host disease, which is a limiting factor to transplantation success. Given that MSCs attain powerful differentiation capabilities and also present immunosuppressive properties, which enable them to survive host immune rejection, MSCs are of great interest. Due to their ability to differentiate into different cell types and to suppress and modulate the immune system, MSCs are being developed for treating a plethora of diseases, including immune disorders. Moreover, in recent years, MSCs have been genetically engineered to treat and sometimes even cure some diseases, and the use of MSCs for cell therapy presents new perspectives for overcoming tissue rejection. In this review, we discuss the potential extrinsic and intrinsic mechanisms that underlie MSCs’ unique ability to modulate inflammation, and both innate and adaptive immunity. PMID:26804815

Gradient complex protective coatings for single-crystal turbine blades of high-heat gas turbine engines

NASA Astrophysics Data System (ADS)

Kuznetsov, V. P.; Lesnikov, V. P.; Muboyadzhyan, S. A.; Repina, O. V.

2007-05-01

Complex diffusion-condensation protective coatings characterized by gradient distribution of alloying elements over the thickness due to formation of a diffusion barrier layer on the surface of blades followed by deposition of condensation alloyed layers based on the Ni-Co-Cr-Al-Y system and an external layer based on a NiAl alloyed β-phase and a ZrO2: Y2O3 ceramics are presented. A complex gradient coating possessing unique protective properties at t = 1100-1200°C for single-crystal blades from alloy ZhS36VI for advanced gas turbine engines with gas temperature of 1550°C at the inlet to the turbine is described.

Mycoplasmosis

USGS Publications Warehouse

Friend, M.

1999-01-01

Mycoplasmosis is caused by infection with a unique group of bacteria that lack cell walls but possess distinctive plasma membranes. Mycoplasma are also the smallest self-replicating life-forms, and they are responsible for a variety of diseases in humans, animals, insects, and plants. These bacteria can cause acute and chronic diseases in hosts that they infect, and they are also implicated with other microbes as causes of disease when the immune system of the host has become impaired through concurrent infection by other disease agents or through other processes. This chapter focuses on mycoplasmal infections of birds, the most significant of which are caused by Mycoplasma gallisepticum (MG), M. meleagridis (MM), and M. synoviae (MS). Only MG is of known importance for wild birds.

Single qubit operations using microwave hyperbolic secant pulses

NASA Astrophysics Data System (ADS)

Ku, H. S.; Long, J. L.; Wu, X.; Bal, M.; Lake, R. E.; Barnes, Edwin; Economou, Sophia E.; Pappas, D. P.

2017-10-01

It has been known since the early days of quantum mechanics that hyperbolic secant pulses possess the unique property that they can perform full-cycle Rabi oscillations on two-level quantum systems independently of the pulse detuning. More recently, it was realized that they induce detuning-controlled phases without changing state populations. Here, we experimentally demonstrate the properties of hyperbolic secant pulses on superconducting transmon qubits and contrast them with the more commonly used Gaussian and square waves. We further show that these properties can be exploited to implement phase gates, nominally without exiting the computational subspace. This enables us to demonstrate a microwave-driven Z rotation with a single control parameter, the detuning.

Distinctive properties of metastasis-initiating cells

PubMed Central

Celià-Terrassa, Toni; Kang, Yibin

2016-01-01

Primary tumors are known to constantly shed a large number of cancer cells into systemic dissemination, yet only a tiny fraction of these cells is capable of forming overt metastases. The tremendous rate of attrition during the process of metastasis implicates the existence of a rare and unique population of metastasis-initiating cells (MICs). MICs possess advantageous traits that may originate in the primary tumor but continue to evolve during dissemination and colonization, including cellular plasticity, metabolic reprogramming, the ability to enter and exit dormancy, resistance to apoptosis, immune evasion, and co-option of other tumor and stromal cells. Better understanding of the molecular and cellular hallmarks of MICs will facilitate the development and deployment of novel therapeutic strategies. PMID:27083997

Mine-hunting dolphins of the Navy

NASA Astrophysics Data System (ADS)

Moore, Patrick W.

1997-07-01

Current counter-mine and obstacle avoidance technology is inadequate, and limits the Navy's capability to conduct shallow water (SW) and very shallow water (VSW) MCM in support of beach assaults by Marine Corps forces. Without information as to the location or density of mined beach areas, it must be assumed that if mines are present in one area then they are present in all areas. Marine mammal systems (MMS) are an unusual, effective and unique solution to current problems of mine and obstacle hunting. In the US Navy Mine Warfare Plan for 1994-1995 Marine Mammal Systems are explicitly identified as the Navy's only means of countering buried mines and the best means for dealing with close-tethered mines. The dolphins in these systems possess a biological sonar specifically adapted for their shallow and very shallow water habitat. Research has demonstrated that the dolphin biosonar outperforms any current hardware system available for SW and VSW applications. This presentation will cover current Fleet MCM systems and future technology application to the littoral region.

Lotka-Volterra representation of general nonlinear systems.

PubMed

Hernández-Bermejo, B; Fairén, V

1997-02-01

In this article we elaborate on the structure of the generalized Lotka-Volterra (GLV) form for nonlinear differential equations. We discuss here the algebraic properties of the GLV family, such as the invariance under quasimonomial transformations and the underlying structure of classes of equivalence. Each class possesses a unique representative under the classical quadratic Lotka-Volterra form. We show how other standard modeling forms of biological interest, such as S-systems or mass-action systems, are naturally embedded into the GLV form, which thus provides a formal framework for their comparison and for the establishment of transformation rules. We also focus on the issue of recasting of general nonlinear systems into the GLV format. We present a procedure for doing so and point at possible sources of ambiguity that could make the resulting Lotka-Volterra system dependent on the path followed. We then provide some general theorems that define the operational and algorithmic framework in which this is not the case.

Cultural Transmission: A View from Chimpanzees and Human Infants.

ERIC Educational Resources Information Center

Tomasello, Michael

2001-01-01

Characterizes primate and human forms of sociality and cultural transmission, describing the ontogeny of human cultural learning (joint attention, imitative learning, and cognitive representation). Humans share most cognitive skills and knowledge with other primates, but they also possess a species-unique social cognitive adaptation that enables…

A New Theoretical Perspective of Cognitive Abilities

ERIC Educational Resources Information Center

Lynch, Sharon A.; Warner, Laverne

2012-01-01

Defining intelligence is a puzzle that has challenged educators and researchers for years. More recently, professionals are acknowledging that individuals possess many facets of intelligence and that learning is a complex combination of genetic factors, environmental influences, and life experiences that affect learning in unique ways (Salvia,…

Teaching Badminton through Play Practice in Physical Education

ERIC Educational Resources Information Center

Kim, Insook

2017-01-01

There is a strong belief that teachers' in-depth content knowledge is key for effective teaching. Teachers who possess specialized content knowledge uniquely needed for teaching are capable of appropriately selecting, sequencing, representing and adapting content applicable for students with different learning needs. Beyond teachers' content…

Supporting Adolescents Exposed to Disasters

ERIC Educational Resources Information Center

Jacobs, Anne K.; Vernberg, Eric; Lee, Stephanie J.

2008-01-01

Adolescents possess numerous strengths and vulnerabilities based on their unique stage of development. When youth experience a disaster, whether natural or human-caused, there are certain considerations to be taken into account when providing them with support. This article describes common adolescent reactions to the impact phase of disasters as…

Spectral tuning in the eyes of deep-sea lanternfishes (Myctophidae): a novel sexually dimorphic intra-ocular filter.

PubMed

de Busserolles, Fanny; Hart, Nathan S; Hunt, David M; Davies, Wayne I; Marshall, N Justin; Clarke, Michael W; Hahne, Dorothee; Collin, Shaun P

2015-01-01

Deep-sea fishes possess several adaptations to facilitate vision where light detection is pushed to its limit. Lanternfishes (Myctophidae), one of the world's most abundant groups of mesopelagic fishes, possess a novel and unique visual specialisation, a sexually dimorphic photostable yellow pigmentation, constituting the first record of a visual sexual dimorphism in any non-primate vertebrate. The topographic distribution of the yellow pigmentation across the retina is species specific, varying in location, shape and size. Spectrophotometric analyses reveal that this new retinal specialisation differs between species in terms of composition and acts as a filter, absorbing maximally between 356 and 443 nm. Microspectrophotometry and molecular analyses indicate that the species containing this pigmentation also possess at least 2 spectrally distinct rod visual pigments as a result of a duplication of the Rh1 opsin gene. After modelling the effect of the yellow pigmentation on photoreceptor spectral sensitivity, we suggest that this unique specialisation acts as a filter to enhance contrast, thereby improving the detection of bioluminescent emissions and possibly fluorescence in the extreme environment of the deep sea. The fact that this yellow pigmentation is species specific, sexually dimorphic and isolated within specific parts of the retina indicates an evolutionary pressure to visualise prey/predators/mates in a particular part of each species' visual field.

Eco-friendly carbon-nanodot-based fluorescent paints for advanced photocatalytic systems

PubMed Central

Young Park, So; Uk Lee, Hyun; Lee, Young-Chul; Choi, Saehae; Hyun Cho, Dae; Sik Kim, Hee; Bang, Sunghee; Seo, Soonjoo; Chang Lee, Soon; Won, Jonghan; Son, Byung-Chul; Yang, Mino; Lee, Jouhahn

2015-01-01

Fluorescent carbon nanomaterials, especially zero-dimensional (0D) carbon nanodots (CDs), are widely used in broad biological and optoelectronic applications. CDs have unique characteristics such as strong fluorescence, biocompatibility, sun-light response, and capability of mass-production. Beyond the previous green CD obtained from harmful natural substances, we report a new type of fluid-based fluorescent CD paints (C-paints) derived from polyethylene glycol (PEG; via simple ultrasound irradiation at room temperatures) and produced in quantum yields of up to ~14%. Additionally, C-paints possess a strong, UV- and visible-light-responsive photoluminescent (PL) property. Most especially, C-paints, by incorporation into a photocatalytic system, show additional roles in the emission of fluorescent light for activation of TiO2 nanoparticles (NPs) and the resultant detoxification of most organic dyes, thus further enabling embarkation in advanced water purification. PMID:26201431

Nicotinic acetylcholine receptor alpha5 subunits modulate oxotremorine-induced salivation and tremor.

PubMed

Wang, Ningshan; Orr-Urtreger, Avi; Chapman, Joab; Rabinowitz, Ruth; Korczyn, Amos D

2004-07-15

Neuronal nicotinic acetylcholine receptors (nAChRs) are composed of 12 subunits (alpha2-alpha10 and beta2-beta4). alpha5 Subunits, expressed throughout the central nervous system (CNS) and the autonomic nervous system (ANS), possess unique pharmacological properties. The effects of oxotremorine (OXO) on autonomic functions and tremor were examined in mice lacking alpha5 nAChR subunits (alpha5-/-) and compared with those in wild-type (WT) control mice. The alpha5-/- mice showed significantly increased salivation and tremor responses to OXO. The hypothermia, bradycardia and defecation induced by OXO were of similar magnitudes in the two mouse strains. The enhanced OXO effects in alpha5-/- mice indicate inhibitory effects of alpha5 subunits in autonomic ganglia, and support the participation of these subunits in cholinergic transmission in autonomic ganglia.

Eco-friendly carbon-nanodot-based fluorescent paints for advanced photocatalytic systems.

PubMed

Park, So Young; Lee, Hyun Uk; Lee, Young-Chul; Choi, Saehae; Cho, Dae Hyun; Kim, Hee Sik; Bang, Sunghee; Seo, Soonjoo; Lee, Soon Chang; Won, Jonghan; Son, Byung-Chul; Yang, Mino; Lee, Jouhahn

2015-07-23

Fluorescent carbon nanomaterials, especially zero-dimensional (0D) carbon nanodots (CDs), are widely used in broad biological and optoelectronic applications. CDs have unique characteristics such as strong fluorescence, biocompatibility, sun-light response, and capability of mass-production. Beyond the previous green CD obtained from harmful natural substances, we report a new type of fluid-based fluorescent CD paints (C-paints) derived from polyethylene glycol (PEG; via simple ultrasound irradiation at room temperatures) and produced in quantum yields of up to ~14%. Additionally, C-paints possess a strong, UV- and visible-light-responsive photoluminescent (PL) property. Most especially, C-paints, by incorporation into a photocatalytic system, show additional roles in the emission of fluorescent light for activation of TiO2 nanoparticles (NPs) and the resultant detoxification of most organic dyes, thus further enabling embarkation in advanced water purification.

Students with Emotional Disturbances: How Can School Counselors Serve?

ERIC Educational Resources Information Center

Miller, Lynne Guillot; Rainey, John S.

2008-01-01

Students with Emotional Disturbances (ED) possess unique characteristics that require additional care from school counselors, teachers, and other school personnel. Information pertaining to the prevalence of ED among students and the common characteristics of students with ED is reviewed. Additionally, ideas and effective approaches that will aid…

Some Current Findings on Brain Characteristics of the Mathematically Gifted Adolescent

ERIC Educational Resources Information Center

O'Boyle, Michael W.

2005-01-01

A number of studies investigating the brain characteristics of mathematically gifted youth indicate that they possess a unique functional organisation as compared to those of average math ability (O'Boyle, et al., 1995). Specifically, data from a variety of behavioural and psychophysiological experiments tend to suggest enhanced processing…

Teaching English Reading through MI Theory in Primary Schools

ERIC Educational Resources Information Center

Jing, Jinxiu

2013-01-01

The theory of Multiple Intelligences (MI theory), put forward by Gardner in 1983, claims that each person possesses different combinations of nine intelligences. In education, it advocates that teachers should address students' personal uniqueness and provide a wide range of intelligence-oriented activities and experiences to facilitate learning,…

Negative dendritic effect on enzymatic hydrolysis of dendrimer conjugates.

PubMed

Zhou, Zhengwei; Cong, Mei; Li, Mengyao; Tintaru, Aura; Li, Jia; Yao, Jianhua; Xia, Yi; Peng, Ling

2018-06-08

Dendrimers possess intriguing "dendritic effects", which are unique characteristics that stem from the dendrimer generation and size. Here we report a "negative dendritic effect" observed during enzymatic hydrolysis of dendrimer conjugates. Such negative dendritic effects, though rarely reported, may be explored for tailored and generation-dependent drug release.

US Colored Troops: A Model for US Army Foreign Army Development and Organization

DTIC Science & Technology

These black troops accounted for 10 percent of US forces. This was a unique experience in US military history, as the United States through unprecedented...and military leaders questioned whether the black soldiers possessed the mental capacity, physical capability, and emotional determination to fight

An Exploration of Hybrid Spaces for Place-Based Geomorphology with Latino Bilingual Children

ERIC Educational Resources Information Center

Martínez-Álvarez, Patricia; Bannan, Brenda

2014-01-01

Latino bilingual children hold rich understandings, which are underexplored and underutilized in the geoscience classroom. Oftentimes, young Latinos possess unique cultural land experiences shaping their place identities. We consider science as language and culture, and propose place-based geoscience hybrid space explorations that are culturally…

19 CFR 123.91 - Electronic information for rail cargo required in advance of arrival.

Code of Federal Regulations, 2013 CFR

2013-04-01

... another vehicle or conveyance is also subject to the advance electronic information filing requirement... a unique number to be assigned by CBP upon the implementation of the Automated Commercial... of the Automated Commercial Environment); (8) The place where the rail carrier takes possession of...

19 CFR 123.91 - Electronic information for rail cargo required in advance of arrival.

Code of Federal Regulations, 2011 CFR

2011-04-01

... another vehicle or conveyance is also subject to the advance electronic information filing requirement... a unique number to be assigned by CBP upon the implementation of the Automated Commercial... of the Automated Commercial Environment); (8) The place where the rail carrier takes possession of...

19 CFR 123.91 - Electronic information for rail cargo required in advance of arrival.

Code of Federal Regulations, 2014 CFR

2014-04-01

... another vehicle or conveyance is also subject to the advance electronic information filing requirement... a unique number to be assigned by CBP upon the implementation of the Automated Commercial... of the Automated Commercial Environment); (8) The place where the rail carrier takes possession of...

19 CFR 123.91 - Electronic information for rail cargo required in advance of arrival.

Code of Federal Regulations, 2012 CFR

2012-04-01

... another vehicle or conveyance is also subject to the advance electronic information filing requirement... a unique number to be assigned by CBP upon the implementation of the Automated Commercial... of the Automated Commercial Environment); (8) The place where the rail carrier takes possession of...

Observations on the quality characteristics of waxy (amylose-free) winter wheats

USDA-ARS?s Scientific Manuscript database

Previous investigations have suggested waxy (amylose-free) wheats (Triticum aestivum L.) possess weak gluten properties and may not be suitable for commercial gluten extraction. This limitation could prevent the use of waxy wheat as a source of unique starch, because gluten is a by-product of the wh...

Descartes and the pineal gland in animals: a frequent misinterpretation.

PubMed

Finger, S

1995-01-01

René Descartes presented a number of reasons for his choice of the pineal gland as a logical place for the soul to interact with the physical machinery of the body. It is often stated that one of his reasons was that he believed animals do not have pineal glands, whereas humans alone possess a soul and this small structure. This is a misinterpretation of Descartes. The philosopher knew that barnyard and other animals possess pineal glands, having seen this with his own eyes. His point was that the pineal is unique in humans only because of a special function - acting as the seat for the rational soul.

Highly compressible 3D periodic graphene aerogel microlattices

PubMed Central

Zhu, Cheng; Han, T. Yong-Jin; Duoss, Eric B.; Golobic, Alexandra M.; Kuntz, Joshua D.; Spadaccini, Christopher M.; Worsley, Marcus A.

2015-01-01

Graphene is a two-dimensional material that offers a unique combination of low density, exceptional mechanical properties, large surface area and excellent electrical conductivity. Recent progress has produced bulk 3D assemblies of graphene, such as graphene aerogels, but they possess purely stochastic porous networks, which limit their performance compared with the potential of an engineered architecture. Here we report the fabrication of periodic graphene aerogel microlattices, possessing an engineered architecture via a 3D printing technique known as direct ink writing. The 3D printed graphene aerogels are lightweight, highly conductive and exhibit supercompressibility (up to 90% compressive strain). Moreover, the Young's moduli of the 3D printed graphene aerogels show an order of magnitude improvement over bulk graphene materials with comparable geometric density and possess large surface areas. Adapting the 3D printing technique to graphene aerogels realizes the possibility of fabricating a myriad of complex aerogel architectures for a broad range of applications. PMID:25902277

Ordering relations for quantum states

NASA Astrophysics Data System (ADS)

Durham, Ian

2015-03-01

It is often desirable to model physical states in an order-theoretic manner, e.g. as a partially ordered set. Classical states are known to possess a unique ordering relation corresponding to a neo-realist interpretation of these states. No such unique relation exists for quantum states. This lack of a unique ordering relation for quantum states turns out to be a manifestation of quantum contextuality vis-à-vis the Kochen-Specker theorem. It also turns out that this provides a link to certain large-scale thermodynamic processes. The suggestion that the ordering of quantum states leads to macroscopic thermodynamic processes is at least five decades old. The suggestion that the mechanism that drives the ordering is contextuality, is unique to this work. The argument is framed in the language of the theories of domains, categories, and topoi. Financial support provided by FQXi.

EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES

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

Brigmon, R; Penny Morris, P; Garriet Smith, G

2008-01-28

Evaporitic environments are found in a variety of depositional environments as early as the Archean. The depositional settings, microbial community and mineralogical composition vary significantly as no two settings are identical. The common thread linking all of the settings is that evaporation exceeds precipitation resulting in elevated concentrations of cations and anions that are higher than in oceanic systems. The Dead Sea and Storrs Lake are examples of two diverse modern evaporitic settings as the former is below sea level and the latter is a coastal lake on an island in the Caribbean. Each system varies in water chemistry asmore » the Dead Sea dissolved ions originate from surface weathered materials, springs, and aquifers while Storrs Lake dissolved ion concentration is primarily derived from sea water. Consequently some of the ions, i.e., Sr, Ba are found at significantly lower concentrations in Storrs Lake than in the Dead Sea. The origin of the dissolved ions are ultimately responsible for the pH of each system, alkaline versus mildly acidic. Each system exhibits unique biogeochemical properties as the extreme environments select certain microorganisms. Storrs Lake possesses significant biofilms and stromatolitic deposits and the alkalinity varies depending on rainfall and storm activity. The microbial community Storrs Lake is much more diverse and active than those observed in the Dead Sea. The Dead Sea waters are mildly acidic, lack stromatolites, and possess a lower density of microbial populations. The general absence of microbial and biofilm fossilization is due to the depletion of HCO{sub 3} and slightly acidic pH.« less

Open Architecture Data System for NASA Langley Combined Loads Test System

NASA Technical Reports Server (NTRS)

Lightfoot, Michael C.; Ambur, Damodar R.

1998-01-01

The Combined Loads Test System (COLTS) is a new structures test complex that is being developed at NASA Langley Research Center (LaRC) to test large curved panels and cylindrical shell structures. These structural components are representative of aircraft fuselage sections of subsonic and supersonic transport aircraft and cryogenic tank structures of reusable launch vehicles. Test structures are subjected to combined loading conditions that simulate realistic flight load conditions. The facility consists of two pressure-box test machines and one combined loads test machine. Each test machine possesses a unique set of requirements or research data acquisition and real-time data display. Given the complex nature of the mechanical and thermal loads to be applied to the various research test articles, each data system has been designed with connectivity attributes that support both data acquisition and data management functions. This paper addresses the research driven data acquisition requirements for each test machine and demonstrates how an open architecture data system design not only meets those needs but provides robust data sharing between data systems including the various control systems which apply spectra of mechanical and thermal loading profiles.

Membrane Asymmetry and Expression of Cell Surface Antigens of Micrococcus lysodeikticus Established by Crossed Immunoelectrophoresis

PubMed Central

Owen, Peter; Salton, Milton R. J.

1977-01-01

Crossed immunoelectrophoresis of Triton X-100-solubilized plasma membranes of Micrococcus lysodeikticus established the presence of 27 discrete antigens. Individual antigens were identified as membrane components possessing enzyme activity by zymogram staining procedures and by reactivity of certain antigens with a selection of four lectins in the crossed-immunoelectrophoresis (immunoaffinoelectrophoresis) system. Absorption experiments with intact, stable protoplasts and isolated membranes established the asymmetric nature of the M. lysodeikticus plasma membranes. Of the 14 antigens with determinants accessible solely on the cytoplasmic face of the membrane, four possessed individual dehydrogenase activities, and a fifth was identifiable as a component possessing adenosine triphosphatase (EC 3.6.1.3) activity. Evidence from absorption studies with isolated membranes suggested that antigens such as the adenosine triphosphatase complex were more readily accessible to reaction with antibodies than was succinate dehydrogenase (EC 1.3.99.1), for example. Twelve antigens were located on the protoplast surface as determined by antibody absorption, and the succinylated lipomannan was identified as a major antigen. At least five other antigens possessed sugar residues that interacted with concanavalin A. With the antisera generated to isolated membranes, there was no evidence suggesting that any of these antigens was not detectable on either surface of the plasma membrane. From absorption experiments with washed, whole cells of M. lysodeikticus, it was concluded that the immunogens on the protoplast surface were also detectable on the surface of the intact cell. However, some of the components such as the succinylated lipomannan appeared to be exposed to a greater extent than others. The cytoplasmic fraction from M. lysodeikticus was used as an antigen source to generate antibodies, and 97 immunoprecipitates were resolvable by crossed immunoelectrophoresis. In the cytoplasm-anticytoplasm reference immunoelectrophoresis pattern of precipitates, three of the immunoprecipitates unique to the cytoplasmic fraction were identifiable by zymogram staining procedures as catalase (EC 1.11.1.6), isocitrate dehydrogenase (EC 1.1.1.42), and polynucleotide phosphorylase (EC 2.3.7.8). The identification of membrane and cytoplasmic antigens (including the above-mentioned enzymes) provides a sensitive analytical system for monitoring cross-contamination and antigen distribution in cellular fractions. Images PMID:144722

Membrane asymmetry and expression of cell surface antigens of Micrococcus lysodeikticus established by crossed immunoelectrophoresis.

PubMed

Owen, P; Salton, M R

1977-12-01

Crossed immunoelectrophoresis of Triton X-100-solubilized plasma membranes of Micrococcus lysodeikticus established the presence of 27 discrete antigens. Individual antigens were identified as membrane components possessing enzyme activity by zymogram staining procedures and by reactivity of certain antigens with a selection of four lectins in the crossed-immunoelectrophoresis (immunoaffinoelectrophoresis) system. Absorption experiments with intact, stable protoplasts and isolated membranes established the asymmetric nature of the M. lysodeikticus plasma membranes. Of the 14 antigens with determinants accessible solely on the cytoplasmic face of the membrane, four possessed individual dehydrogenase activities, and a fifth was identifiable as a component possessing adenosine triphosphatase (EC 3.6.1.3) activity. Evidence from absorption studies with isolated membranes suggested that antigens such as the adenosine triphosphatase complex were more readily accessible to reaction with antibodies than was succinate dehydrogenase (EC 1.3.99.1), for example. Twelve antigens were located on the protoplast surface as determined by antibody absorption, and the succinylated lipomannan was identified as a major antigen. At least five other antigens possessed sugar residues that interacted with concanavalin A. With the antisera generated to isolated membranes, there was no evidence suggesting that any of these antigens was not detectable on either surface of the plasma membrane. From absorption experiments with washed, whole cells of M. lysodeikticus, it was concluded that the immunogens on the protoplast surface were also detectable on the surface of the intact cell. However, some of the components such as the succinylated lipomannan appeared to be exposed to a greater extent than others. The cytoplasmic fraction from M. lysodeikticus was used as an antigen source to generate antibodies, and 97 immunoprecipitates were resolvable by crossed immunoelectrophoresis. In the cytoplasm-anticytoplasm reference immunoelectrophoresis pattern of precipitates, three of the immunoprecipitates unique to the cytoplasmic fraction were identifiable by zymogram staining procedures as catalase (EC 1.11.1.6), isocitrate dehydrogenase (EC 1.1.1.42), and polynucleotide phosphorylase (EC 2.3.7.8). The identification of membrane and cytoplasmic antigens (including the above-mentioned enzymes) provides a sensitive analytical system for monitoring cross-contamination and antigen distribution in cellular fractions.

Tracking Hole Transport in DNA Hairpins Using a Phenylethynylguanine Nucleobase.

PubMed

Brown, Kristen E; Singh, Arunoday P N; Wu, Yi-Lin; Mishra, Ashutosh Kumar; Zhou, Jiawang; Lewis, Frederick D; Young, Ryan M; Wasielewski, Michael R

2017-08-30

The hole transport dynamics of DNA hairpins possessing a stilbene electron acceptor and donor along with a modified guanine (G) nucleobase, specifically 8-(4'-phenylethynyl)deoxyguanosine, or EG, have been investigated. The nearly indistinguishable oxidation potentials of EG and G and unique spectroscopic characteristics of EG +• make it well-suited for directly observing transient hole occupation during charge transport between a stilbene electron donor and acceptor. In contrast to the cation radical G +• , EG +• possesses a strong absorption near 460 nm and has a distinct Raman-active ethynyl stretch. Both spectroscopic characteristics are easily distinguished from those of the stilbene donor/acceptor radical ion chromophores. Employing EG, we observe its role as a shallow hole trap, or as an intermediate hole transport site when a deeper trap state is present. Using a combination of ultrafast absorption and stimulated Raman spectroscopies, the hole-transport dynamics are observed to be similar in systems having EG vs G bases, with small perturbations to the charge transport rates and yields. These results show EG can be deployed at specified locations throughout the sequence to report on hole occupancy, thereby enabling detailed monitoring of the hole transport dynamics with base-site specificity.

Emerging applications of nanoparticles: Biomedical and environmental

NASA Astrophysics Data System (ADS)

Gulati, Shivani; Sachdeva, M.; Bhasin, K. K.

2018-05-01

Nanotechnology finds a wide range of applications from energy production to industrial fabrication processes to biomedical applications. Nanoparticles (NPs) can be engineered to possess unique compositions and functionalities to empower novel tools and techniques that have not existed previously in biomedical research. The unique size and shape dependent physicochemical properties along with their unique spectral and optical properties have prompted the development of a wide variety of potential applications in the field of diagnostics and medicines. In the plethora of scientific and technological fields, environmental safety is also a big concern. For this purpose, nanomaterials have been functionalized to cope up the existing pollution, improving manufacturing methods to reduce the generation of new pollution, and making alternative and more cost effective energy sources.

Haunted by ghosts: prevalence, predictors and outcomes of spirit possession experiences among former child soldiers and war-affected civilians in Northern Uganda.

PubMed

Neuner, Frank; Pfeiffer, Anett; Schauer-Kaiser, Elisabeth; Odenwald, Michael; Elbert, Thomas; Ertl, Verena

2012-08-01

Phenomena of spirit possession have been documented in many cultures. Some authors have argued that spirit possession is a type of psychopathology, and should be included as a category in diagnostic manuals of mental disorders. However, there are hardly any quantitative studies that report the prevalence of spirit possession on a population level and that provide evidence for its validity as a psychopathological entity. In an epidemiological study that was carried out in 2007 and 2008 with N = 1113 youths and young adults aged between 12 and 25 years in war-affected regions of Northern Uganda we examined the prevalence, predictors and outcomes of cen, a local variant of spirit possession. Randomly selected participants were interviewed using a scale of cen, measures of psychopathology (PTSD and depression) as well as indicators of functional outcome on different levels, including suicide risk, daily activities, perceived discrimination, physical complaints and aggression. We found that cen was more common among former child soldiers then among subjects without a history of abduction. Cen was related to extreme levels of traumatic events and uniquely predicted functional outcome even when the effects of PTSD and depression were controlled for. Our findings show that a long-lasting war that is accompanied by the proliferation of spiritual and magical beliefs and propaganda can lead to high levels of harmful spirit possession. In addition, we provide evidence for the incremental validity of spirit possession as a trauma-related psychological disorder in this context. Copyright © 2012 Elsevier Ltd. All rights reserved.

Achieving Balance Through the Art of Eating: Demystifying Eastern Nutrition and Blending it with Western Nutrition.

PubMed

Wongvibulsin, Shannon; Lee, Suzie Seoyang; Hui, Ka-Kit

2012-01-01

Eastern and Western approaches to nutrition are unique and possess both strengths and weaknesses. Blending the best of both techniques will allow for the development of an integrative nutrition system that is more effective than either tradition on its own. The Western view to nutrition is already adopting certain attributes of the Eastern medicine philosophy as exemplified by the progression towards individualized nutrition through methods such as nutrigenetics. Nevertheless, many differences still remain between Eastern and Western nutritional concepts. Becoming fluent in both Western and Eastern methodologies can ensure the extraction of the best from both techniques for the development of a comprehensive, systematic, and holistic nutritional approach to achieve optimal health.

Nanochemistry of Protein-Based Delivery Agents

PubMed Central

Rajendran, Subin R. C. K.; Udenigwe, Chibuike C.; Yada, Rickey Y.

2016-01-01

The past decade has seen an increased interest in the conversion of food proteins into functional biomaterials, including their use for loading and delivery of physiologically active compounds such as nutraceuticals and pharmaceuticals. Proteins possess a competitive advantage over other platforms for the development of nanodelivery systems since they are biocompatible, amphipathic, and widely available. Proteins also have unique molecular structures and diverse functional groups that can be selectively modified to alter encapsulation and release properties. A number of physical and chemical methods have been used for preparing protein nanoformulations, each based on different underlying protein chemistry. This review focuses on the chemistry of the reorganization and/or modification of proteins into functional nanostructures for delivery, from the perspective of their preparation, functionality, stability and physiological behavior. PMID:27489854

Nanochemistry of protein-based delivery agents

NASA Astrophysics Data System (ADS)

Rajendran, Subin; Udenigwe, Chibuike; Yada, Rickey

2016-07-01

The past decade has seen an increased interest in the conversion of food proteins into functional biomaterials, including their use for loading and delivery of physiologically active compounds such as nutraceuticals and pharmaceuticals. Proteins possess a competitive advantage over other platforms for the development of nanodelivery systems since they are biocompatible, amphipathic, and widely available. Proteins also have unique molecular structures and diverse functional groups that can be selectively modified to alter encapsulation and release properties. A number of physical and chemical methods have been used for preparing protein nanoformulations, each based on different underlying protein chemistry. This review focuses on the chemistry of the reorganization and/or modification of proteins into functional nanostructures for delivery, from the perspective of their preparation, functionality, stability and physiological behavior.

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

Not Available

Reflecting Secretary O`Leary`s focus on occupational safety and health, the Office of Occupational Safety is pleased to provide you with the latest update to the DOE Interpretations Guide to OSH Standards. This Guide was developed in cooperation with the Occupational Safety and Health Administration, which continued its support during this last revision by facilitating access to the interpretations found on the OSHA Computerized Information System (OCIS). This March 31, 1994 update contains 123 formal interpretation letters written by OSHA. As a result of the unique requests received by the 1-800 Response Line, this update also contains 38 interpretations developed bymore » DOE. This new occupational safety and health information adds still more important guidance to the four volume reference set that you presently have in your possession.« less

Achieving Balance Through the Art of Eating: Demystifying Eastern Nutrition and Blending it with Western Nutrition

PubMed Central

Wongvibulsin, Shannon; Lee, Suzie Seoyang; Hui, Ka-Kit

2012-01-01

Eastern and Western approaches to nutrition are unique and possess both strengths and weaknesses. Blending the best of both techniques will allow for the development of an integrative nutrition system that is more effective than either tradition on its own. The Western view to nutrition is already adopting certain attributes of the Eastern medicine philosophy as exemplified by the progression towards individualized nutrition through methods such as nutrigenetics. Nevertheless, many differences still remain between Eastern and Western nutritional concepts. Becoming fluent in both Western and Eastern methodologies can ensure the extraction of the best from both techniques for the development of a comprehensive, systematic, and holistic nutritional approach to achieve optimal health. PMID:24716109

Neurocognitive mechanisms underlying social learning in infancy: infants' neural processing of the effects of others' actions.

PubMed

Paulus, Markus; Hunnius, Sabine; Bekkering, Harold

2013-10-01

Social transmission of knowledge is one of the reasons for human evolutionary success, and it has been suggested that already human infants possess eminent social learning abilities. However, nothing is known about the neurocognitive mechanisms that subserve infants' acquisition of novel action knowledge through the observation of other people's actions and their consequences in the physical world. In an electroencephalogram study on social learning in infancy, we demonstrate that 9-month-old infants represent the environmental effects of others' actions in their own motor system, although they never achieved these effects themselves before. The results provide first insights into the neurocognitive basis of human infants' unique ability for social learning of novel action knowledge.

Learning Style Activities for Computer Applications. Field Review.

ERIC Educational Resources Information Center

Patton, Jan

This document contains a composite of learning activities for use in a secondary-level course in business computer applications. The collection is unique in that the individual learning activities constituting it have each been tailored to one or more of the diverse learning styles possessed by individual students. The activities are grouped into…

Assessing and Treating Childhood Anxiety in School Settings

ERIC Educational Resources Information Center

Wright, Savannah; Sulkowski, Michael L.

2013-01-01

As professionals who often know the most about psychology in school settings and education in clinical settings and because of the importance of addressing both academic and mental health needs in anxious youth, school psychologists are uniquely positioned to assist anxious students. School psychologists possess a dynamic skill set that can be…

Paying Attention to Culture: An Autoethnographic Study of a Principal in Transition

ERIC Educational Resources Information Center

Klingaman, Danielle E.

2012-01-01

Beginning a new principalship is a complex endeavor where novice and seasoned school administrators must follow a cautious and deliberate plan of action. Every school possesses a unique culture and identity that includes its history, traditions, norms, and values. Understanding and respecting this culture is essential as an outsider entering this…

Sociolinguistic Awareness and False Belief in Young Cantonese Learners of English

ERIC Educational Resources Information Center

Cheung, Him; Mak, Wing Yan; Luo, Xueying; Xiao, Wen

2010-01-01

In this study, we examined whether sociolinguistic awareness and false belief were uniquely related in 3- and 4-year-old Cantonese-speaking children learning English as a second language. The English-use background of these children varied so that they possessed sociolinguistic awareness to different degrees. Results indicated that sociolinguistic…

22 CFR 51.1 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... photograph, a unique chip number, and a digital signature to protect the integrity of the stored information... territories and possessions. (k) U.S. citizen means a person who acquired U.S. citizenship at birth or upon naturalization as provided by law and who has not subsequently lost such citizenship. (l) U.S. national means a U...

Dimensionally Stable Ether-Containing Polyimide Copolymers

NASA Technical Reports Server (NTRS)

Fay, Catharine C. (Inventor); St.Clair, Anne K. (Inventor)

1999-01-01

Novel polyimide copolymers containing ether linkages were prepared by the reaction of an equimolar amount of dianhydride and a combination of diamines. The polyimide copolymers described herein possess the unique features of low moisture uptake, dimensional stability, good mechanical properties, and moderate glass transition temperatures. These materials have potential application as encapsulants and interlayer dielectrics.

Synthesis of a Near-Infrared Emitting Squaraine Dye in an Undergraduate Organic Laboratory

ERIC Educational Resources Information Center

Marks, Patrick; Levine, Mindy

2012-01-01

Squaraines are a class of organic fluorophores that possess unique photophysical properties, including strong near-infrared absorption and emission. The synthesis of many squaraines involves the condensation of an electron-rich aromatic ring with squaric acid. These reactions are generally refluxed overnight in a benzene-butanol solvent mixture.…

19 CFR 123.91 - Electronic information for rail cargo required in advance of arrival.

Code of Federal Regulations, 2010 CFR

2010-04-01

... transportation and exportation, in another vehicle or conveyance is also subject to the advance electronic... identification number will be a unique number to be assigned by CBP upon the implementation of the Automated... implementation of the Automated Commercial Environment); (8) The place where the rail carrier takes possession of...

Craig Buthod: Librarian of the Year 2010!

ERIC Educational Resources Information Center

Berry, John N., III

2010-01-01

This article profiles Craig Buthod, director of the Louisville Free Public Library (LFPL) who is named "LJ"'s 2010 Librarian of the Year. An ability to convert setbacks into opportunities is the key to the successful career of Craig Buthod. Buthod possesses a unique combination of optimism, managerial talent, political savvy, and a…

The Relationship between Perceptions of School Climate and Student Achievement in Schools That Use Jostens' Renaissance Programs

ERIC Educational Resources Information Center

Coyne, Amy Yarborough

2012-01-01

Each school has unique attributes and a personality that gives the school a distinct climate. Psychological qualities that schools possess might include trust, collaboration, cooperation, teaching attributes, expectations, community involvement, and engagement (Rhodes, Camic, Milburn, & Lowe, 2009). Given information regarding school climate,…

Addressing Uniqueness and Unison of Reliability and Safety for a Better Integration

NASA Technical Reports Server (NTRS)

Huang, Zhaofeng; Safie, Fayssal

2016-01-01

Over time, it has been observed that Safety and Reliability have not been clearly differentiated, which leads to confusion, inefficiency, and, sometimes, counter-productive practices in executing each of these two disciplines. It is imperative to address this situation to help Reliability and Safety disciplines improve their effectiveness and efficiency. The paper poses an important question to address, "Safety and Reliability - Are they unique or unisonous?" To answer the question, the paper reviewed several most commonly used analyses from each of the disciplines, namely, FMEA, reliability allocation and prediction, reliability design involvement, system safety hazard analysis, Fault Tree Analysis, and Probabilistic Risk Assessment. The paper pointed out uniqueness and unison of Safety and Reliability in their respective roles, requirements, approaches, and tools, and presented some suggestions for enhancing and improving the individual disciplines, as well as promoting the integration of the two. The paper concludes that Safety and Reliability are unique, but compensating each other in many aspects, and need to be integrated. Particularly, the individual roles of Safety and Reliability need to be differentiated, that is, Safety is to ensure and assure the product meets safety requirements, goals, or desires, and Reliability is to ensure and assure maximum achievability of intended design functions. With the integration of Safety and Reliability, personnel can be shared, tools and analyses have to be integrated, and skill sets can be possessed by the same person with the purpose of providing the best value to a product development.

A high-density lipoprotein-mediated drug delivery system.

PubMed

Mo, Zhong-Cheng; Ren, Kun; Liu, Xing; Tang, Zhen-Li; Yi, Guang-Hui

2016-11-15

High-density lipoprotein (HDL) is a comparatively dense and small lipoprotein that can carry lipids as a multifunctional aggregate in plasma. Several studies have shown that increasing the levels or improving the functionality of HDL is a promising target for treating a wide variety of diseases. Among lipoproteins, HDL particles possess unique physicochemical properties, including naturally synthesized physiological components, amphipathic apolipoproteins, lipid-loading and hydrophobic agent-incorporating characteristics, specific protein-protein interactions, heterogeneity, nanoparticles, and smaller size. Recently, the feasibility and superiority of using HDL particles as drug delivery vehicles have been of great interest. In this review, we summarize the structure, constituents, biogenesis, remodeling, and reconstitution of HDL drug delivery systems, focusing on their delivery capability, characteristics, applications, manufacturing, and drug-loading and drug-targeting characteristics. Finally, the future prospects are presented regarding the clinical application and challenges of using HDL as a pharmacodelivery carrier. Copyright © 2016 Elsevier B.V. All rights reserved.

E-health in graduate and postgraduate medical education: illusions, expectations and reality.

PubMed

Bari, Ferenc; Forczek, Erzsébet; Hantos, Zoltán

2011-01-01

With the overall growth of informatics, the medical education system should also provide programs at both graduate and post-graduate levels. While there is a wide consensus as to the importance of this urgent need, several factors slow down the construction and operation of effective education programs in medical and nursing schools. The increasing need for better and more comprehensive training in informatics is strongly limited by several factors including undefined output skills, tight time frame etc. An efficient development of partnerships within the health care system assumes that all professionals involved must possess strong informatics and interpersonal knowledge, and skills reaching beyond their own individual fields. There is an emerging need to define the basic skills and knowledge for each level of the health care education. Trans-border cooperation offers a unique opportunity for the establishment of common criteria for basic skills and knowledge, via joint discussions, collaborative thinking and concerted action.

Zein-based Nanocarriers as Potential Natural Alternatives for Drug and Gene Delivery: Focus on Cancer Therapy.

PubMed

Elzoghby, Ahmed; Freag, May; Mamdouh, Hadeer; Elkhodairy, Kadria

2017-01-01

Protein nanocarriers possess unique merits including minimal cytotoxicity, numerous renewable sources, and high drug-binding capability. In opposition to delivery carriers utilizing hydrophilic animal proteins, hydrophobic plant proteins (e.g, zein) have great tendency in fabricating controlled-release particulate carriers without additional chemical modification to stiffen them, which in turn evades the use of toxic chemical crosslinkers. Moreover, zein is related to a class of alcohol-soluble prolamins and generally recognized as safe (GRAS) carrier for drug delivery. Various techniques have been adopted to fabricate zein-based nanoparticulate systems including phase separation coacervation, spray-drying, supercritical anti-solvent approach, electrospinning and self-assembly. This manuscript reviews the recent advances in the zein-based colloidal nano-carrier systems such as nanospheres, nanocapsules, micelles and nanofibers with a special focus on their physicochemical characteristics and drug delivery applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Hybrid Vibrio cholerae El Tor Lacking SXT Identified as the Cause of a Cholera Outbreak in the Philippines

PubMed Central

Klinzing, David C.; Choi, Seon Young; Hasan, Nur A.; Matias, Ronald R.; Tayag, Enrique; Geronimo, Josefina; Skowronski, Evan; Rashed, Shah M.; Kawashima, Kent; Rosenzweig, C. Nicole; Gibbons, Henry S.; Torres, Brian C.; Liles, Veni; Alfon, Alicia C.; Juan, Maria Luisa; Natividad, Filipinas F.; Cebula, Thomas A.

2015-01-01

ABSTRACT Cholera continues to be a global threat, with high rates of morbidity and mortality. In 2011, a cholera outbreak occurred in Palawan, Philippines, affecting more than 500 people, and 20 individuals died. Vibrio cholerae O1 was confirmed as the etiological agent. Source attribution is critical in cholera outbreaks for proper management of the disease, as well as to control spread. In this study, three V. cholerae O1 isolates from a Philippines cholera outbreak were sequenced and their genomes analyzed to determine phylogenetic relatedness to V. cholerae O1 isolates from recent outbreaks of cholera elsewhere. The Philippines V. cholerae O1 isolates were determined to be V. cholerae O1 hybrid El Tor belonging to the seventh-pandemic clade. They clustered tightly, forming a monophyletic clade closely related to V. cholerae O1 hybrid El Tor from Asia and Africa. The isolates possess a unique multilocus variable-number tandem repeat analysis (MLVA) genotype (12-7-9-18-25 and 12-7-10-14-21) and lack SXT. In addition, they possess a novel 15-kb genomic island (GI-119) containing a predicted type I restriction-modification system. The CTXΦ-RS1 array of the Philippines isolates was similar to that of V. cholerae O1 MG116926, a hybrid El Tor strain isolated in Bangladesh in 1991. Overall, the data indicate that the Philippines V. cholerae O1 isolates are unique, differing from recent V. cholerae O1 isolates from Asia, Africa, and Haiti. Furthermore, the results of this study support the hypothesis that the Philippines isolates of V. cholerae O1 are indigenous and exist locally in the aquatic ecosystem of the Philippines. PMID:25900650

Self-Healing Behavior of Ethylene-Based Ionomers

NASA Technical Reports Server (NTRS)

Kalista, Stephen J., Jr.; Ward, Thomas C.; Oyetunji, Zainab

2004-01-01

The self-healing behavior of poly(ethylene-co-methacrylic acid) (EMAA)-based ionomers holds tremendous potential for use in a wide variety of unique applications. However, to effectively utilize this self-healing behavior and to design novel materials which possess this ability, the mechanism by which they heal must first be understood ionomers are a class of polymers that can be described as copolymers containing less than 15 mol% ionic content whereby the bulk properties are governed by ionic interactions within the polymer. These ionic groups aggregate into discrete regions known as multiplets which overlap forming clusters that act as physical cross-links profoundly influencing the bulk physical properties. These clusters possess an order-disorder transition (T(sub i)) where the clustered regions may rearrange themselves given time and stimuli. Recognizing the strong influence of these ionic regions on other well understood ionomer properties, their role in self-heating behavior will be assessed. The self-healing behavior is observed following projectile puncture. It has been suggested that during impact energy is passed to the ionomer material, heating it to the melt state. After penetration, it is proposed that the ionic regions maintain their attractions and flow together patching the hole. Thus, the importance of this ionic character and is unique interaction must be established. This will be accomplished through examination of materials with varying ionic content and through the analysis of the T(sub i). The specific ionomer systems examined include a number of ethylene-based materials. Materials of varying ionic content, including the non-ionic base copolymers, will be examined by peel tests, projectile impact and DSC analysis. The information will also be compared with some basic data on LDPE material.

Highly intense monocycle terahertz vortex generation by utilizing a Tsurupica spiral phase plate

PubMed Central

Miyamoto, Katsuhiko; Kang, Bong Joo; Kim, Won Tae; Sasaki, Yuta; Niinomi, Hiromasa; Suizu, Koji; Rotermund, Fabian; Omatsu, Takashige

2016-01-01

Optical vortex, possessing an annular intensity profile and an orbital angular momentum (characterized by an integer termed a topological charge) associated with a helical wavefront, has attracted great attention for diverse applications due to its unique properties. In particular for terahertz (THz) frequency range, several approaches for THz vortex generation, including molded phase plates consisting of metal slit antennas, achromatic polarization elements and binary-diffractive optical elements, have been recently proposed, however, they are typically designed for a specific frequency. Here, we demonstrate highly intense broadband monocycle vortex generation near 0.6 THz by utilizing a polymeric Tsurupica spiral phase plate in combination with tilted-pulse-front optical rectification in a prism-cut LiNbO3 crystal. A maximum peak power of 2.3 MW was obtained for THz vortex output with an expected topological charge of 1.15. Furthermore, we applied the highly intense THz vortex beam for studying unique nonlinear behaviors in bilayer graphene towards the development of nonlinear super-resolution THz microscopy and imaging system. PMID:27966595

Carotenoid composition of the flowers of Mimulus lewisii and related species: Implications regarding the prevalence and origin of two unique, allenic pigments.

PubMed

LaFountain, Amy M; Frank, Harry A; Yuan, Yao-Wu

2015-05-01

The genus Mimulus has been used as a model system in a wide range of ecological and evolutionary studies and contains many species with carotenoid pigmented flowers. However, the detailed carotenoid composition of these flowers has never been reported. In this paper the floral carotenoid composition of 11 Mimulus species are characterized using high-performance liquid chromatography, mass spectrometry and chemical methods with a particular focus on the genetic model species, Mimulus lewisii. M. lewisii flowers have five major carotenoids: antheraxanthin, violaxanthin, neoxanthin, and the unique allenic carotenoids, deepoxyneoxanthin and mimulaxanthin. This carotenoid profile is consistent with the expression levels of putative carotenoid biosynthetic genes in the M. lewisii flower. The other 10 species possess the same five carotenoids or a subset of these. Comparison of the carotenoid profiles among species in a phylogenetic context provides new insights into the biosynthesis and evolution of deepoxyneoxanthin and mimulaxanthin. This work also lays the foundation for future studies regarding transcriptional control of the carotenoid biosynthesis pathway in Mimulus flowers. Copyright © 2015 Elsevier Inc. All rights reserved.

Geometry in Biomimetic Network: Double Gyroid to Pseudo-Single Gyroid in Nanohybrid Materials

NASA Astrophysics Data System (ADS)

Hsueh, Han-Yu; Ho, Rong-Ming; Hung, Yu-Chueh; Ling, Yi-Chun; Hasegawa, Hirokazu

2013-03-01

Biological systems have developed delicately arranged micro- and architectures to produce striking optical effects since millions of years ago. Inspired by the textures of butterfly wings with single gyroid (SG) structure, herein, we aim to fabricate biocompatible and robust materials with SG-like structure in nanometer size so as to give new materials with unprecedented optical properties for applications. Biommicking from the biological photonic structures of butterfly wings, a double gyroid (DG) structure in nanometer size is obtained from the self-assembly of polystyrene-b-poly(L-lactide) (PS-PLLA). To acquire robust backbone networks, inorganic networks in polymer matrix are fabricated by using the hydrolyzed PS-PLLA with DG structure as a template for sol-gel reaction. Owing to the soft polymer matrix, two co-continuous inorganic networks embedded in the polymer matrix can be rearranged by thermal annealing at temperature above the glass transition of the polymer. Consequently, the rearrangement of these inorganic networks leads the formation of SG-like structure possessing unique nanohybrids with ordered texture. This unique nanomaterials with SG-like structure is referred as a pseudo-SG (p-SG) nanohybrids.

Integrated Vehicle Ground Vibration Testing in Support of Launch Vehicle Loads and Controls Analysis

NASA Technical Reports Server (NTRS)

Askins, Bruce R.; Davis, Susan R.; Salyer, Blaine H.; Tuma, Margaret L.

2008-01-01

All structural systems possess a basic set of physical characteristics unique to that system. These unique physical characteristics include items such as mass distribution and damping. When specified, they allow engineers to understand and predict how a structural system behaves under given loading conditions and different methods of control. These physical properties of launch vehicles may be predicted by analysis or measured by certain types of tests. Generally, these properties are predicted by analysis during the design phase of a launch vehicle and then verified by testing before the vehicle becomes operational. A ground vibration test (GVT) is intended to measure by test the fundamental dynamic characteristics of launch vehicles during various phases of flight. During the series of tests, properties such as natural frequencies, mode shapes, and transfer functions are measured directly. These data will then be used to calibrate loads and control systems analysis models for verifying analyses of the launch vehicle. NASA manned launch vehicles have undergone ground vibration testing leading to the development of successful launch vehicles. A GVT was not performed on the inaugural launch of the unmanned Delta III which was lost during launch. Subsequent analyses indicated had a GVT been performed, it would have identified instability issues avoiding loss of the vehicle. This discussion will address GVT planning, set-up, execution and analyses, for the Saturn and Shuttle programs, and will also focus on the current and on-going planning for the Ares I and V Integrated Vehicle Ground Vibration Test (IVGVT).

The Potent Respiratory System of Osedax mucofloris (Siboglinidae, Annelida) - A Prerequisite for the Origin of Bone-Eating Osedax?

PubMed Central

Huusgaard, Randi S.; Vismann, Bent; Kühl, Michael; Macnaugton, Martin; Colmander, Veronica; Rouse, Greg W.; Glover, Adrian G.; Dahlgren, Thomas; Worsaae, Katrine

2012-01-01

Members of the conspicuous bone-eating genus, Osedax, are widely distributed on whale falls in the Pacific and Atlantic Oceans. These gutless annelids contain endosymbiotic heterotrophic bacteria in a branching root system embedded in the bones of vertebrates, whereas a trunk and anterior palps extend into the surrounding water. The unique life style within a bone environment is challenged by the high bacterial activity on, and within, the bone matrix possibly causing O2 depletion, and build-up of potentially toxic sulphide. We measured the O2 distribution around embedded Osedax and showed that the bone microenvironment is anoxic. Morphological studies showed that ventilation mechanisms in Osedax are restricted to the anterior palps, which are optimized for high O2 uptake by possessing a large surface area, large surface to volume ratio, and short diffusion distances. The blood vascular system comprises large vessels in the trunk, which facilitate an ample supply of oxygenated blood from the anterior crown to a highly vascularised root structure. Respirometry studies of O. mucofloris showed a high O2 consumption that exceeded the average O2 consumption of a broad line of resting annelids without endosymbionts. We regard this combination of features of the respiratory system of O. mucofloris as an adaptation to their unique nutrition strategy with roots embedded in anoxic bones and elevated O2 demand due to aerobic heterotrophic endosymbionts. PMID:22558289

Evaluation and implementation of QR Code Identity Tag system for Healthcare in Turkey.

PubMed

Uzun, Vassilya; Bilgin, Sami

2016-01-01

For this study, we designed a QR Code Identity Tag system to integrate into the Turkish healthcare system. This system provides QR code-based medical identification alerts and an in-hospital patient identification system. Every member of the medical system is assigned a unique QR Code Tag; to facilitate medical identification alerts, the QR Code Identity Tag can be worn as a bracelet or necklace or carried as an ID card. Patients must always possess the QR Code Identity bracelets within hospital grounds. These QR code bracelets link to the QR Code Identity website, where detailed information is stored; a smartphone or standalone QR code scanner can be used to scan the code. The design of this system allows authorized personnel (e.g., paramedics, firefighters, or police) to access more detailed patient information than the average smartphone user: emergency service professionals are authorized to access patient medical histories to improve the accuracy of medical treatment. In Istanbul, we tested the self-designed system with 174 participants. To analyze the QR Code Identity Tag system's usability, the participants completed the System Usability Scale questionnaire after using the system.

Cloning, expression, purification, crystallization and preliminary X-ray crystallographic investigations of a unique editing domain from archaebacteria.

PubMed

Dwivedi, Shweta; Kruparani, Shobha P; Sankaranarayanan, Rajan

2004-09-01

Threonyl-tRNA synthetase (ThrRS) faces a crucial double-discrimination problem during the translation of genetic code. Most ThrRSs from the archaeal kingdom possess a unique editing domain that differs from those of eubacteria and eukaryotes. In order to understand the structural basis of the editing mechanism in archaea, the editing module of ThrRS from Pyrococcus abyssi comprising of the first 183 amino-acid residues was cloned, expressed, purified and crystallized. The crystals belong to the trigonal space group P3(1(2))21, with one molecule in the asymmetric unit.

Graphene electrochemistry: an overview of potential applications.

PubMed

Brownson, Dale A C; Banks, Craig E

2010-11-01

Graphene, a 2D nanomaterial that possesses spectacular physical, chemical and thermal properties, has caused immense excitement amongst scientists since its freestanding form was isolated in 2004. With research into graphene rife, it promises enhancements and vast applicability within many industrial aspects. Furthermore, graphene possesses a vast array of unique and highly desirable electrochemical properties, and it is this application that offers the most enthralling and spectacular journey. We present a review of the current literature concerning the electrochemical applications and advancements of graphene, starting with its use as a sensor substrate through to applications in energy production and storage, depicting the truly remarkable journey of a material that has just come of age.

Nitrogen modulation of legume root architecture signaling pathways involves phytohormones and small regulatory molecules.

PubMed

Mohd-Radzman, Nadiatul A; Djordjevic, Michael A; Imin, Nijat

2013-10-01

Nitrogen, particularly nitrate is an important yield determinant for crops. However, current agricultural practice with excessive fertilizer usage has detrimental effects on the environment. Therefore, legumes have been suggested as a sustainable alternative for replenishing soil nitrogen. Legumes can uniquely form nitrogen-fixing nodules through symbiotic interaction with specialized soil bacteria. Legumes possess a highly plastic root system which modulates its architecture according to the nitrogen availability in the soil. Understanding how legumes regulate root development in response to nitrogen availability is an important step to improving root architecture. The nitrogen-mediated root development pathway starts with sensing soil nitrogen level followed by subsequent signal transduction pathways involving phytohormones, microRNAs and regulatory peptides that collectively modulate the growth and shape of the root system. This review focuses on the current understanding of nitrogen-mediated legume root architecture including local and systemic regulations by different N-sources and the modulations by phytohormones and small regulatory molecules.

Surface modification of nanoparticles enables selective evasion of phagocytic clearance by distinct macrophage phenotypes

NASA Astrophysics Data System (ADS)

Qie, Yaqing; Yuan, Hengfeng; von Roemeling, Christina A.; Chen, Yuanxin; Liu, Xiujie; Shih, Kevin D.; Knight, Joshua A.; Tun, Han W.; Wharen, Robert E.; Jiang, Wen; Kim, Betty Y. S.

2016-05-01

Nanomedicine is a burgeoning industry but an understanding of the interaction of nanomaterials with the immune system is critical for clinical translation. Macrophages play a fundamental role in the immune system by engulfing foreign particulates such as nanoparticles. When activated, macrophages form distinct phenotypic populations with unique immune functions, however the mechanism by which these polarized macrophages react to nanoparticles is unclear. Furthermore, strategies to selectively evade activated macrophage subpopulations are lacking. Here we demonstrate that stimulated macrophages possess higher phagocytic activities and that classically activated (M1) macrophages exhibit greater phagocytic capacity than alternatively activated (M2) macrophages. We show that modification of nanoparticles with polyethylene-glycol results in decreased clearance by all macrophage phenotypes, but importantly, coating nanoparticles with CD47 preferentially lowers phagocytic activity by the M1 phenotype. These results suggest that bio-inspired nanoparticle surface design may enable evasion of specific components of the immune system and provide a rational approach for developing immune tolerant nanomedicines.

Advances in neuroimmunology

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

Raine, C.S.

1988-01-01

This volume presents the proceedings of the Second International Congress of Neuroimmunology. It brought together basic researchers and clinicians involved in the application of immunologic methodologies to the elucidation of problems related to nervous system development and disease. Neuroimmunology as a discipline is still in its infancy although its roots date back more than 50 years when it was realized that certain neurologic disorders were related to allergic reactions. Since then, it has been shown that immunological mechanisms are involved not only in a growing number of disease processes of the nervous system, but also in the development of nervousmore » tissue. It is now widely accepted that the nervous system shares a unique relationship with the immune system, sometimes through shared receptors, and possesses a large repertoire of specific antigens. Thus, with the continuing and intensive application of immunologic techniques to the neurologic sciences, the specialty of neuroimmunology has evolved. The major diseases that now fall into its realm include multiple sclerosis, myasthenia gravis, peripheral neuropathy, systemic lupus erythematosus, AIDS, leprosy, narcolepsy, tumors, viral encephalitis, and their experimental counterparts.« less

Application of nanotechnology in miniaturized systems and its use for advanced analytics and diagnostics - an updated review.

PubMed

Sandetskaya, Natalia; Allelein, Susann; Kuhlmeier, Dirk

2013-12-01

A combination of Micro-Electro-Mechanical Systems and nanoscale structures allows for the creation of novel miniaturized devices, which broaden the boundaries of the diagnostic approaches. Some materials possess unique properties at the nanolevel, which are different from those in bulk materials. In the last few years these properties became a focus of interest for many researchers, as well as methods of production, design and operation of the nanoobjects. Intensive research and development work resulted in numerous inventions exploiting nanotechnology in miniaturized systems. Modern technical and laboratory equipment allows for the precise control of such devices, making them suitable for sensitive and accurate detection of the analytes. The current review highlights recent patents in the field of nanotechnology in microdevices, applicable for medical, environmental or food analysis. The paper covers the structural and functional basis of such systems and describes specific embodiments in three principal branches: application of nanoparticles, nanofluidics, and nanosensors in the miniaturized systems for advanced analytics and diagnostics. This overview is an update of an earlier review article.

Evolution of Fe/S cluster biogenesis in the anaerobic parasite Blastocystis

PubMed Central

Tsaousis, Anastasios D.; Ollagnier de Choudens, Sandrine; Gentekaki, Eleni; Long, Shaojun; Gaston, Daniel; Stechmann, Alexandra; Vinella, Daniel; Py, Béatrice; Fontecave, Marc; Barras, Frédéric; Lukeš, Julius; Roger, Andrew J.

2012-01-01

Iron/sulfur cluster (ISC)-containing proteins are essential components of cells. In most eukaryotes, Fe/S clusters are synthesized by the mitochondrial ISC machinery, the cytosolic iron/sulfur assembly system, and, in photosynthetic species, a plastid sulfur-mobilization (SUF) system. Here we show that the anaerobic human protozoan parasite Blastocystis, in addition to possessing ISC and iron/sulfur assembly systems, expresses a fused version of the SufC and SufB proteins of prokaryotes that it has acquired by lateral transfer from an archaeon related to the Methanomicrobiales, an important lineage represented in the human gastrointestinal tract microbiome. Although components of the Blastocystis ISC system function within its anaerobic mitochondrion-related organelles and can functionally replace homologues in Trypanosoma brucei, its SufCB protein has similar biochemical properties to its prokaryotic homologues, functions within the parasite’s cytosol, and is up-regulated under oxygen stress. Blastocystis is unique among eukaryotic pathogens in having adapted to its parasitic lifestyle by acquiring a SUF system from nonpathogenic Archaea to synthesize Fe/S clusters under oxygen stress. PMID:22699510

Overproduction of Hydrogen From an Anaerobic Bacterium

DTIC Science & Technology

2008-12-01

fixation of nitrogen ( Haber - Bosch process), mostly to produce fertilizer. Nitrogenase provides a catalytic alternative to the commercial fixation of...the culture and suggests a uniquely simple hydrogen reactor design based on renewable feedstocks. 1. INTRODUCTION Hydrogen is an ideal... renewable feedstocks. Clostridium phytofermentans is a recently- discovered anaerobic bacterium, reported to possess cellulase enzymes that degrade

Elongation Factor-1a is a novel protein associated with host cell invasion and a potential protective antigen of Cryptosporidium parvum*

USDA-ARS?s Scientific Manuscript database

The phylum Apicomplexa comprises obligate intracellular parasites that infect vertebrates. All invasive forms of Apicomplexa possess a unique complex of organelles at the anterior end, referred to as the apical complex, which is involved in host cell invasion. Previously, we generated the chicken m...

Child vs. Adult in Second Language Acquisition: Some Reflections.

ERIC Educational Resources Information Center

Banu, Rahela

The popular view that children have an advantage in learning a second language has considerable support in research, although it is not uncontested. One approach proposes that the child possesses a unique capacity for language that the adult no longer has. Another view argues that the child's brain is more flexible. A third approach assumes that…

Essential Points of a Support Network Approach for School Counselors Working with Children Diagnosed with Asperger's

ERIC Educational Resources Information Center

Guo, Yuh-Jen; Wang, Shu-Ching; Corbin-Burdick, Marilyn F.; Statz, Shelly R.

2013-01-01

Asperger Syndrome (AS) presents unique challenges to both families and schools. Children diagnosed with Asperger's possess unparalleled characteristics in cognitive functioning and behavioral pattern. These children need extra attention and assistance in schools. School counselors require a strategy to successfully engage and support these…

Wrapping the Curriculum around Their Lives: Using a Culturally Relevant Curriculum with African American Adult Women

ERIC Educational Resources Information Center

Sealey-Ruiz, Yolanda

2007-01-01

This study examines how African American adult female students respond to a culturally relevant curriculum. Research confirms that adults enter college classrooms with a variety of experiences that they value and experiences to which they wish to connect. Black female students in particular possess knowledge unique to their positionality in…

Educating Somali Immigrant and Refugee Students: A Review of Cultural-Historical Issues and Related Psychoeducational Supports

ERIC Educational Resources Information Center

Walick, Christopher M.; Sullivan, Amanda L.

2015-01-01

Somali immigrants and refugees have entered the United States with increasing frequency due to civil war-induced violence and instability in their native country. The resultant increase of Somali students is of particular relevance to educators and school psychologists because Somali youth possess unique cultural backgrounds. In addition, refugee…

Athletic Trainers' Perceptions of the Importance, Preparation and Time Spent in the Athletic Training Content Areas

ERIC Educational Resources Information Center

Donahue, Martin

2009-01-01

Context: Graduates of professional programs accredited by the Commission on Accreditation of Athletic Training Education are expected to be competent and proficient in the athletic training content areas. Objective: The unique skills and knowledge that an athletic trainer (AT) must possess may have more importance in one clinical setting than in…

Does Creativity Impact Scientific Aptitude of School Children?

ERIC Educational Resources Information Center

Jayalekshmi, N. B.; Raja, B. William Dharma

2011-01-01

Of all the equalities man possesses, creative thinking has been the most important for his well being and advancement. Creativity means to make, to bring into being, to originate or to invent something. Scientific aptitude is considered to be a unique or unusual potential or ability of an individual to acquire general knowledge and skill in…

Personalizing Group Environments: A Conceptual Approach Toward More Effective Small Group Functioning.

ERIC Educational Resources Information Center

Beach, Wayne A.

A conceptual approach toward more effective small group functioning is undertaken in this paper to provide a basis from which empirically relevant hypotheses can be drawn and tested. This analysis views actualizing individuals as possessing the unique ability to perceive and utilize the types of behaviors which are conducive to personalizing group…

Female forestland owners: Characterization of assistance needs

Treesearch

Sarah Day Crim; Mark Dubois; Conner Bailey; John Schelhas

2003-01-01

There is a limited amount of research focusing on female forestland owners. In looking at female forestland owners as a group researchers are often left with more questions than answers. What is the role of these landowners in the forestry sector? How do female forestland owners manage their lands? Do female forestland owners possess unique characteristics, needs, and...

Educational Justice for All: The Capability Approach and Inclusive Education Leadership

ERIC Educational Resources Information Center

Toson, Amy L.-M.; Burrello, Leonard C.; Knollman, Gregory

2013-01-01

Leaders within education must weigh a number of fundamentals as they engage the needs of the stakeholders they represent within the political, social and economic context they operate within. Leaders must consider the unique needs and capabilities of individuals who might not possess similar abilities or talents to those of the majority. In this…

Electronic structure and superconductivity of FeSe-related superconductors.

PubMed

Liu, Xu; Zhao, Lin; He, Shaolong; He, Junfeng; Liu, Defa; Mou, Daixiang; Shen, Bing; Hu, Yong; Huang, Jianwei; Zhou, X J

2015-05-13

FeSe superconductors and their related systems have attracted much attention in the study of iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a superconducting transition temperature (Tc) of ~8 K and it can be dramatically enhanced to 37 K at high pressure. On the other hand, its cousin system, FeTe, possesses a unique antiferromagnetic ground state but is non-superconducting. Substitution of Se with Te in the FeSe superconductor results in an enhancement of Tc up to 14.5 K and superconductivity can persist over a large composition range in the Fe(Se,Te) system. Intercalation of the FeSe superconductor leads to the discovery of the AxFe2-ySe2 (A = K, Cs and Tl) system that exhibits a Tc higher than 30 K and a unique electronic structure of the superconducting phase. A recent report of possible high temperature superconductivity in single-layer FeSe/SrTiO3 films with a Tc above 65 K has generated much excitement in the community. This pioneering work opens a door for interface superconductivity to explore for high Tc superconductors. The distinct electronic structure and superconducting gap, layer-dependent behavior and insulator-superconductor transition of the FeSe/SrTiO3 films provide critical information in understanding the superconductivity mechanism of iron-based superconductors. In this paper, we present a brief review of the investigation of the electronic structure and superconductivity of the FeSe superconductor and related systems, with a particular focus on the FeSe films.

Fabrication of polyurethane and polyurethane based composite fibres by the electrospinning technique for soft tissue engineering of cardiovascular system.

PubMed

Kucinska-Lipka, J; Gubanska, I; Janik, H; Sienkiewicz, M

2015-01-01

Electrospinning is a unique technique, which provides forming of polymeric scaffolds for soft tissue engineering, which include tissue scaffolds for soft tissues of the cardiovascular system. Such artificial soft tissues of the cardiovascular system may possess mechanical properties comparable to native vascular tissues. Electrospinning technique gives the opportunity to form fibres with nm- to μm-scale in diameter. The arrangement of obtained fibres and their surface determine the biocompatibility of the scaffolds. Polyurethanes (PUs) are being commonly used as a prosthesis of cardiovascular soft tissues due to their excellent biocompatibility, non-toxicity, elasticity and mechanical properties. PUs also possess fine spinning properties. The combination of a variety of PU properties with an electrospinning technique, conducted at the well tailored conditions, gives unlimited possibilities of forming novel polyurethane materials suitable for soft tissue scaffolds applied in cardiovascular tissue engineering. This paper can help researches to gain more widespread and deeper understanding of designing electrospinable PU materials, which may be used as cardiovascular soft tissue scaffolds. In this paper we focus on reagents used in PU synthesis designed to increase PU biocompatibility (polyols) and biodegradability (isocyanates). We also describe suggested surface modifications of electrospun PUs, and the direct influence of surface wettability on providing enhanced biocompatibility of scaffolds. We indicate a great influence of electrospinning parameters (voltage, flow rate, working distance) and used solvents (mostly DMF, THF and HFIP) on fibre alignment and diameter - what impacts the biocompatibility and hemocompatibility of such electrospun PU scaffolds. Moreover, we present PU modifications with natural polymers with novel approach applied in electrospinning of PU scaffolds. This work may contribute with further developing of novel electrospun PUs, which may be applied as soft tissue scaffolds of the cardiovascular system. Copyright © 2014. Published by Elsevier B.V.

Highly compressible 3D periodic graphene aerogel microlattices

DOE PAGES

Zhu, Cheng; Han, T. Yong-Jin; Duoss, Eric B.; ...

2015-04-22

Graphene is a two-dimensional material that offers a unique combination of low density, exceptional mechanical properties, large surface area and excellent electrical conductivity. Recent progress has produced bulk 3D assemblies of graphene, such as graphene aerogels, but they possess purely stochastic porous networks, which limit their performance compared with the potential of an engineered architecture. Here we report the fabrication of periodic graphene aerogel microlattices, possessing an engineered architecture via a 3D printing technique known as direct ink writing. The 3D printed graphene aerogels are lightweight, highly conductive and exhibit supercompressibility (up to 90% compressive strain). Moreover, the Young’s modulimore » of the 3D printed graphene aerogels show an order of magnitude improvement over bulk graphene materials with comparable geometric density and possess large surface areas. Ultimately, adapting the 3D printing technique to graphene aerogels realizes the possibility of fabricating a myriad of complex aerogel architectures for a broad range of applications.« less

Cognitive capacities for cooking in chimpanzees

PubMed Central

Warneken, Felix; Rosati, Alexandra G.

2015-01-01

The transition to a cooked diet represents an important shift in human ecology and evolution. Cooking requires a set of sophisticated cognitive abilities, including causal reasoning, self-control and anticipatory planning. Do humans uniquely possess the cognitive capacities needed to cook food? We address whether one of humans' closest relatives, chimpanzees (Pan troglodytes), possess the domain-general cognitive skills needed to cook. Across nine studies, we show that chimpanzees: (i) prefer cooked foods; (ii) comprehend the transformation of raw food that occurs when cooking, and generalize this causal understanding to new contexts; (iii) will pay temporal costs to acquire cooked foods; (iv) are willing to actively give up possession of raw foods in order to transform them; and (v) can transport raw food as well as save their raw food in anticipation of future opportunities to cook. Together, our results indicate that several of the fundamental psychological abilities necessary to engage in cooking may have been shared with the last common ancestor of apes and humans, predating the control of fire. PMID:26041356

High-Definition Self-Assemblies driven by the Hydrophobic Effect: Synthesis and Properties of a Supramolecular Nano-Capsule

PubMed Central

Liu, Simin

2008-01-01

High definition self-assemblies, those that possess order at the molecular level, are most commonly made from subunits possessing metals and metal coordination sites, or groups capable of partaking in hydrogen bonding. In other words, enthalpy is the driving force behind the free energy of assembly. The hydrophobic effect engenders the possibility of (nominally) relying not on enthalpy but entropy to drive assembly. Towards this idea, we describe how template molecules can trigger the dimerization of a cavitand in aqueous solution, and in doing so are encapsulated within the resulting capsule. Although not held together by (enthalpically) strong and directional non-covalent forces, these capsules possess considerable thermodynamic and kinetic stability. As a result, they display unusual and even unique properties. We discuss some of these, including the use of the capsule as a nano-scale reaction chamber and how they can bring about the separation of hydrocarbon gases. PMID:18685753

Histology of the heterostracan dermal skeleton: Insight into the origin of the vertebrate mineralised skeleton.

PubMed

Keating, Joseph N; Marquart, Chloe L; Donoghue, Philip C J

2015-06-01

Living vertebrates are divided into those that possess a fully formed and fully mineralised skeleton (gnathostomes) versus those that possess only unmineralised cartilaginous rudiments (cyclostomes). As such, extinct phylogenetic intermediates of these living lineages afford unique insights into the evolutionary assembly of the vertebrate mineralised skeleton and its canonical tissue types. Extinct jawless and jawed fishes assigned to the gnathostome stem evidence the piecemeal assembly of skeletal systems, revealing that the dermal skeleton is the earliest manifestation of a homologous mineralised skeleton. Yet the nature of the primitive dermal skeleton, itself, is poorly understood. This is principally because previous histological studies of early vertebrates lacked a phylogenetic framework required to derive evolutionary hypotheses. Nowhere is this more apparent than within Heterostraci, a diverse clade of primitive jawless vertebrates. To this end, we surveyed the dermal skeletal histology of heterostracans, inferred the plesiomorphic heterostracan skeleton and, through histological comparison to other skeletonising vertebrate clades, deduced the ancestral nature of the vertebrate dermal skeleton. Heterostracans primitively possess a four-layered skeleton, comprising a superficial layer of odontodes composed of dentine and enameloid; a compact layer of acellular parallel-fibred bone containing a network of vascular canals that supply the pulp canals (L1); a trabecular layer consisting of intersecting radial walls composed of acellular parallel-fibred bone, showing osteon-like development (L2); and a basal layer of isopedin (L3). A three layered skeleton, equivalent to the superficial layer L2 and L3 and composed of enameloid, dentine and acellular bone, is possessed by the ancestor of heterostracans + jawed vertebrates. We conclude that an osteogenic component is plesiomorphic with respect to the vertebrate dermal skeleton. Consequently, we interpret the dermal skeleton of denticles in chondrichthyans and jawless thelodonts as independently and secondarily simplified. J. Morphol. 276:657-680, 2015. © 2015 The Authors Journal of Morphology Published by Wiley Periodicals, Inc. © 2015 The Authors Journal of Morphology Published by Wiley Periodicals, Inc.

Moiré edge states in twisted graphene nanoribbons

NASA Astrophysics Data System (ADS)

Fleischmann, M.; Gupta, R.; Weckbecker, D.; Landgraf, W.; Pankratov, O.; Meded, V.; Shallcross, S.

2018-05-01

The edge physics of graphene based systems is well known to be highly sensitive to the atomic structure at the boundary, with localized zero mode edge states found only on the zigzag-type termination of the lattice. Here we demonstrate that the graphene twist bilayer supports an additional class of edge states, that (i) are found for all edge geometries and thus are robust against edge roughness, (ii) occur at energies coinciding with twist induced Van Hove singularities in the bulk and (iii) possess an electron density strongly modulated by the moiré lattice. Interestingly, these "moiré edge states" exist only for certain lattice commensurations and thus the edge physics of the twist bilayer is, in dramatic contrast to that of the bulk, not uniquely determined by the twist angle.

[Fish interferon response and its molecular regulation: a review].

PubMed

Zhang, Yibing; Gui, Jianfang

2011-05-01

Interferon response is the first line of host defense against virus infection. Recent years have witnessed tremendous progress in understanding of fish innate response to virus infection, especially in fish interferon antiviral response. A line of fish genes involved in interferon antiviral response have been identified and functional studies further reveal that fish possess an IFN antiviral system similar to mammals. However, fish virus-induced interferon genes contain introns similar to mammalian type III interferon genes although they encode proteins similar to type I interferons, which makes it hard to understand the evolution of vertebrate interferon genes directly resulting in a debate on nomenclature of fish interferon genes. Actually, fish display some unique mechanisms underlying interferon antiviral response. This review documents the recent progress on fish interferon response and its molecular mechanism.

Integrating Lung Physiology, Immunology, and Tuberculosis.

PubMed

Torrelles, Jordi B; Schlesinger, Larry S

2017-08-01

Lungs are directly exposed to the air, have enormous surface area, and enable gas exchange in air-breathing animals. They are constantly 'attacked' by microbes from both outside and inside and thus possess a unique, highly regulated local immune defense system which efficiently allows for microbial clearance while minimizing damaging inflammatory responses. As a prototypic host-adapted airborne pathogen, Mycobacterium tuberculosis traverses the lung and has several 'interaction points' (IPs) which it must overcome to cause infection. These interactions are critical, not only from a pathogenesis perspective but also in considering the effectiveness of therapies and vaccines in the lungs. Here we discuss emerging views on immunologic interactions occurring in the lungs for M. tuberculosis and their impact on infection and persistence. Copyright © 2017 Elsevier Ltd. All rights reserved.

Eaten alive: novel insights into autophagy from multicellular model systems.

PubMed

Zhang, Hong; Baehrecke, Eric H

2015-07-01

Autophagy delivers cytoplasmic material to lysosomes for degradation. First identified in yeast, the core genes that control this process are conserved in higher organisms. Studies of mammalian cell cultures have expanded our understanding of the core autophagy pathway, but cannot reveal the unique animal-specific mechanisms for the regulation and function of autophagy. Multicellular organisms have different types of cells that possess distinct composition, morphology, and organization of intracellular organelles. In addition, the autophagic machinery integrates signals from other cells and environmental conditions to maintain cell, tissue and organism homeostasis. Here, we highlight how studies of autophagy in flies and worms have identified novel core autophagy genes and mechanisms, and provided insight into the context-specific regulation and function of autophagy. Copyright © 2015 Elsevier Ltd. All rights reserved.

Review of Adaptive Programmable Materials and Their Bioapplications.

PubMed

Fan, Xiaoshan; Chung, Jing Yang; Lim, Yong Xiang; Li, Zibiao; Loh, Xian Jun

2016-12-14

Adaptive programmable materials have attracted increasing attention due to their high functionality, autonomous behavior, encapsulation, and site-specific confinement capabilities in various applications. Compared to conventional materials, adaptive programmable materials possess unique single-material architecture that can maintain, respond, and change their shapes and dimensions when they are subjected to surrounding environment changes, such as alternation in temperature, pH, and ionic strength. In this review, the most-recent advances in the design strategies of adaptive programmable materials are presented with respect to different types of architectural polymers, including stimuli-responsive polymers and shape-memory polymers. The diverse functions of these sophisticated materials and their significance in therapeutic agent delivery systems are also summarized in this review. Finally, the challenges for facile fabrication of these materials and future prospective are also discussed.

The CD8 T-cell response during tolerance induction in liver transplantation

PubMed Central

Wong, Yik Chun; McCaughan, Geoffrey W; Bowen, David G; Bertolino, Patrick

2016-01-01

Both experimental and clinical studies have shown that the liver possesses unique tolerogenic properties. Liver allografts can be spontaneously accepted across complete major histocompatibility mismatch in some animal models. In addition, some liver transplant patients can be successfully withdrawn from immunosuppressive medications, developing ‘operational tolerance'. Multiple mechanisms have been shown to be involved in inducing and maintaining alloimmune tolerance associated with liver transplantation. Here, we focus on CD8 T-cell tolerance in this setting. We first discuss how alloreactive cytotoxic T-cell responses are generated against allografts, before reviewing how the liver parenchyma, donor passenger leucocytes and the host immune system function together to attenuate alloreactive CD8 T-cell responses to promote the long-term survival of liver transplants. PMID:27867515

Biosafe Nanoscale Pharmaceutical Adjuvant Materials

PubMed Central

Jin, Shubin; Li, Shengliang; Wang, Chongxi; Liu, Juan; Yang, Xiaolong; Wang, Paul C.; Zhang, Xin; Liang, Xing-Jie

2014-01-01

Thanks to developments in the field of nanotechnology over the past decades, more and more biosafe nanoscale materials have become available for use as pharmaceutical adjuvants in medical research. Nanomaterials possess unique properties which could be employed to develop drug carriers with longer circulation time, higher loading capacity, better stability in physiological conditions, controlled drug release, and targeted drug delivery. In this review article, we will review recent progress in the application of representative organic, inorganic and hybrid biosafe nanoscale materials in pharmaceutical research, especially focusing on nanomaterial-based novel drug delivery systems. In addition, we briefly discuss the advantages and notable functions that make these nanomaterials suitable for the design of new medicines; the biosafety of each material discussed in this article is also highlighted to provide a comprehensive understanding of their adjuvant attributes. PMID:25429253

Colonize, evade, flourish

PubMed Central

Rubin, Erica J; Trent, M Stephen

2013-01-01

Helicobacter pylori is an adapted gastric pathogen that colonizes the human stomach, causing severe gastritis and gastric cancer. A hallmark of infection is the ability of this organism to evade detection by the human immune system. H. pylori has evolved a number of features to achieve this, many of which involve glyco-conjugates including the lipopolysaccharide, peptidoglycan layer, glycoproteins, and glucosylated cholesterol. These major bacterial components possess unique features from those of other gram-negative organisms, including differences in structure, assembly, and modification. These defining characteristics of H. pylori glycobiology help the pathogen establish a long-lived infection by providing camouflage, modulating the host immune response, and promoting virulence mechanisms. In this way, glyco-conjugates are essential for H. pylori pathogenicity and survival, allowing it to carve out a niche in the formidable environment of the human stomach. PMID:23859890

Visual guidance in control of grasping.

PubMed

Janssen, Peter; Scherberger, Hansjörg

2015-07-08

Humans and other primates possess a unique capacity to grasp and manipulate objects skillfully, a facility pervasive in everyday life that has undoubtedly contributed to the success of our species. When we reach and grasp an object, various cortical areas in the parietal and frontal lobes work together effortlessly to analyze object shape and position, transform this visual information into useful motor commands, and implement these motor representations to preshape the hand before contact with the object is made. In recent years, a growing number of studies have investigated the neural circuits underlying object grasping in both the visual and motor systems of the macaque monkey. The accumulated knowledge not only helps researchers understand how object grasping is implemented in the primate brain but may also contribute to the development of novel neural interfaces and neuroprosthetics.

Two distinct RNase activities of CRISPR-C2c2 enable guide-RNA processing and RNA detection.

PubMed

East-Seletsky, Alexandra; O'Connell, Mitchell R; Knight, Spencer C; Burstein, David; Cate, Jamie H D; Tjian, Robert; Doudna, Jennifer A

2016-10-13

Bacterial adaptive immune systems use CRISPRs (clustered regularly interspaced short palindromic repeats) and CRISPR-associated (Cas) proteins for RNA-guided nucleic acid cleavage. Although most prokaryotic adaptive immune systems generally target DNA substrates, type III and VI CRISPR systems direct interference complexes against single-stranded RNA substrates. In type VI systems, the single-subunit C2c2 protein functions as an RNA-guided RNA endonuclease (RNase). How this enzyme acquires mature CRISPR RNAs (crRNAs) that are essential for immune surveillance and how it carries out crRNA-mediated RNA cleavage remain unclear. Here we show that bacterial C2c2 possesses a unique RNase activity responsible for CRISPR RNA maturation that is distinct from its RNA-activated single-stranded RNA degradation activity. These dual RNase functions are chemically and mechanistically different from each other and from the crRNA-processing behaviour of the evolutionarily unrelated CRISPR enzyme Cpf1 (ref. 11). The two RNase activities of C2c2 enable multiplexed processing and loading of guide RNAs that in turn allow sensitive detection of cellular transcripts.

Amblypygids: Model Organisms for the Study of Arthropod Navigation Mechanisms in Complex Environments?

PubMed Central

Wiegmann, Daniel D.; Hebets, Eileen A.; Gronenberg, Wulfila; Graving, Jacob M.; Bingman, Verner P.

2016-01-01

Navigation is an ideal behavioral model for the study of sensory system integration and the neural substrates associated with complex behavior. For this broader purpose, however, it may be profitable to develop new model systems that are both tractable and sufficiently complex to ensure that information derived from a single sensory modality and path integration are inadequate to locate a goal. Here, we discuss some recent discoveries related to navigation by amblypygids, nocturnal arachnids that inhabit the tropics and sub-tropics. Nocturnal displacement experiments under the cover of a tropical rainforest reveal that these animals possess navigational abilities that are reminiscent, albeit on a smaller spatial scale, of true-navigating vertebrates. Specialized legs, called antenniform legs, which possess hundreds of olfactory and tactile sensory hairs, and vision appear to be involved. These animals also have enormous mushroom bodies, higher-order brain regions that, in insects, integrate contextual cues and may be involved in spatial memory. In amblypygids, the complexity of a nocturnal rainforest may impose navigational challenges that favor the integration of information derived from multimodal cues. Moreover, the movement of these animals is easily studied in the laboratory and putative neural integration sites of sensory information can be manipulated. Thus, amblypygids could serve as model organisms for the discovery of neural substrates associated with a unique and potentially sophisticated navigational capability. The diversity of habitats in which amblypygids are found also offers an opportunity for comparative studies of sensory integration and ecological selection pressures on navigation mechanisms. PMID:27014008

Return to Play After Shoulder Surgery in Throwers.

PubMed

Thorsness, Robert; Alland, Jeremy A; McCulloch, Colin B; Romeo, Anthony

2016-10-01

The throwing athlete's shoulder is a unique, complex entity with challenges in diagnosis and management. The shoulders in these athletes possess unique biomechanics and pathologic conditions. Unfortunately, return to play outcomes are often poor when specifically evaluating overhead athletes, especially with regard to SLAP repair. It is imperative for the surgeon to be cautious when indicating these athletes for surgery, because although they may demonstrate improvements in pain and general function, subtle changes in accuracy or velocity as a result of surgery can significantly affect the success of an overhead throwing athlete at the competitive level. Copyright © 2016 Elsevier Inc. All rights reserved.

Evidence for Dynamic Chemical Kinetics at Individual Molecular Ruthenium Catalysts.

PubMed

Easter, Quinn T; Blum, Suzanne A

2018-02-05

Catalytic cycles are typically depicted as possessing time-invariant steps with fixed rates. Yet the true behavior of individual catalysts with respect to time is unknown, hidden by the ensemble averaging inherent to bulk measurements. Evidence is presented for variable chemical kinetics at individual catalysts, with a focus on ring-opening metathesis polymerization catalyzed by the second-generation Grubbs' ruthenium catalyst. Fluorescence microscopy is used to probe the chemical kinetics of the reaction because the technique possesses sufficient sensitivity for the detection of single chemical reactions. Insertion reactions in submicron regions likely occur at groups of many (not single) catalysts, yet not so many that their unique kinetic behavior is ensemble averaged. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Novel bacterial ADP-ribosylating toxins: structure and function

PubMed Central

Simon, Nathan C.; Aktories, Klaus; Barbieri, Joseph T.

2018-01-01

Preface Bacterial ADP-ribosyltransferase toxins (bARTTs) transfer ADP-ribose to eukaryotic proteins to promote bacterial pathogenesis. In this review we use prototype bARTTs, such as diphtheria and pertussis toxins, as references for the characterization of several new bARTTs from human, insect, and plant pathogens, which were identified recently through bioinformatic analyses. Several of these toxins, including Cholix toxin from Vibrio cholerae, SpyA from Streptococcus pyogenes, HopU1 from Pseudomonas syringae, and the Tcc toxins from Photorhabdus luminescens, ADP-ribosylate novel substrates and possess unique organizations, which distinguish them from the reference toxins. The characterization of these toxins extends our appreciation for the variety of structure-function properties possessed by bARTTs and their roles in bacterial pathogenesis. PMID:25023120

Development of Thermally Stable and Highly Fluorescent IR Dyes

NASA Technical Reports Server (NTRS)

Bu, Xiu R.

2004-01-01

Fluorophores are the core component in various optical applications such as sensors and probes. Fluorphores with low-energy or long wavelength emission, in particular, in NIR region, possess advantages of low interference and high sensitivity. In this study, we has explored several classes of imidazole-based compounds for NIR fluorescent properties and concluded: (1) thiazole-based imidazole compounds are fluorescent; (2) emission energy is tunable by additional donor groups; (3) they also possess impressive two- photon absorption properties; and (4) fluorescence emission can be induced by two- photon input. This report summarizes (1) synthesis of new series of fluorophore; (2) impact of electron-withdrawing groups on fluorescent property; (3) unique property of two-photon absorption; and (4) on-going development.

The Timelessness of Art as Epitomized in Shelley's "Ozymandias"

ERIC Educational Resources Information Center

Daiya, Krishna

2014-01-01

Percy Bysshe Shelley was a poet whose name itself is a Metaphor for exquisite, rhythmic poetry laden with images of Nature as well as Man. He possesses the magical power of transporting the reader into an alternative world with the unique use of metaphors and imagery. His personal sadness was translated into sweet songs that are echoed in the…

Investigating the Development of Science-Literate Identities through a Multicultural Perspective

ERIC Educational Resources Information Center

Oemig, Paulo A.; Baptiste, H. Prentice

2018-01-01

The complexity of learning science rests in the fact that it not only possesses a unique lexicon and discourse but also that it ultimately entails a way of knowing. This article involves a case study that examines the academic engagement and perceptions of a group (N = 30) of high school students regarding their science literacy practices. These…

Quantitative Determination of Iron in Limonite Using Spectroscopic Methods with Senior and General Chemistry Students: Geology-Inspired Chemistry Lab Explorations

ERIC Educational Resources Information Center

Bopegedera, A. M. R. P.; Coughenour, Christopher L.; Oswalt, Andrew J.

2016-01-01

Limonite is the field term for a mixed assemblage of ferric oxyhydroxides, often containing nonferric silicate impurities. It is abundant on Earth's surface, possesses variable iron content, and is easily recognized by distinctive yellow and ochre hues. Limonite is a unique centerpiece for undergraduate chemistry laboratories because each sample…

Portrait of the College Employee: Work "Em" to Death, or Just Leave "Em" Alone

ERIC Educational Resources Information Center

Simplicio, Joseph

2010-01-01

This article discusses work inequalities that currently exist within many of the nation's colleges. It does so by identifying two distinct groups of individuals who possess unique qualities that make them stand apart from one another. Each practice a special type of work ethic philosophy that helps define it as employees and as people. Through the…

Expansion of Biology Teachers' Pedagogical Content Knowledge (PCK) during a Long-Term Professional Development Program

ERIC Educational Resources Information Center

Rozenszajn, Ronit; Yarden, Anat

2014-01-01

Experienced teachers possess a unique teaching knowledge comprised of an inter-related set of knowledge and beliefs that gives direction and justification to a teacher's actions. This study examined the expansion of two components of pedagogical content knowledge (PCK) of three in-service teachers in the course of a professional development…

'Caro-Tex 312’ – An F1 Hybrid, High Yielding, Multiple Disease Resistant, Orange Habanero Pepper Cultivar

USDA-ARS?s Scientific Manuscript database

Texas A&M University and the USDA-ARS U.S. Vegetable Laboratory in Charleston, SC, have developed a new, F1 hybrid Habanero pepper cultivar. ‘Caro-Tex 312’ produces a large, orange-fruited Habanero pepper with typical shape and high pungency. It also possesses unique yield, early maturity and dise...

An Inner-City School Mentor: A Narrative Inquiry of the Life Experiences of "Daddy"

ERIC Educational Resources Information Center

Li, Xin; Lal, Dhyan

2006-01-01

A two-year ethnographic observation of an inner-city high school in Los Angeles, USA, indicated that the principal, who was extremely dedicated to at-risk students and possessed a unique style of mentoring, played a major role in students academic achievement. We--the principal and the researcher who observed the school--inquired about the…

Wetlands of the Prairie Pothole Region: Invertebrate species composition, ecology, and management

USGS Publications Warehouse

Euliss, N.H.; Wrubleski, D.A.; Mushet, D.M.; Batzer, D.P.; Rader, R.B.; Wissinger, S.A.

1999-01-01

The Prairie Pothole Region (PPR) of the United States and Canada is a unique area where shallow depressions created by the scouring action of Pleistocene glaciation interact with mid-continental climate variations to create and maintain a variety of wetland classes. These wetlands possess unique environmental and biotic characteristics that add to the overall regional diversity and production of aquatic invertebrates and the vertebrate wildlife that depend upon them as food. Climatic extremes in the PPR have a profound and dynamic influence on wetland hydrology, hydroperiod, chemistry, and ultimately the biota. Available knowledge of aquatic invertebrates in the PPR suggests that diversity of invertebrates within each wetland class is low. Harsh environmental conditions range from frigid winter temperatures that freeze wetlands and their sediments to hot summer temperatures and drought conditions that create steep salinity gradients and seasonally dry habitats. Consequently, the invertebrate community is composed mostly of ecological generalists that possess the necessary adaptations to tolerate environmental extremes. In this review, we describe the highly dynamic nature of prairie pothole wetlands and suggest that invertebrate studies be evaluated within a conceptual framework that considers important hydrologic, chemical, and climatic events.

Chordate evolution and the origin of craniates: an old brain in a new head.

PubMed

Butler, A B

2000-06-15

The earliest craniates achieved a unique condition among bilaterally symmetrical animals: they possessed enlarged, elaborated brains with paired sense organs and unique derivatives of neural crest and placodal tissues, including peripheral sensory ganglia, visceral arches, and head skeleton. The craniate sister taxon, cephalochordates, has rostral portions of the neuraxis that are homologous to some of the major divisions of craniate brains. Moreover, recent data indicate that many genes involved in patterning the nervous system are common to all bilaterally symmetrical animals and have been inherited from a common ancestor. Craniates, thus, have an "old" brain in a new head, due to re-expression of these anciently acquired genes. The transition to the craniate brain from a cephalochordate-like ancestral form may have involved a mediolateral shift in expression of the genes that specify nervous system development from various parts of the ectoderm. It is suggested here that the transition was sequential. The first step involved the presence of paired, lateral eyes, elaboration of the alar plate, and enhancement of the descending visual pathway to brainstem motor centers. Subsequently, this central visual pathway served as a template for the additional sensory systems that were elaborated and/or augmented with the "bloom" of migratory neural crest and placodes. This model accounts for the marked uniformity of pattern across central sensory pathways and for the lack of any neural crest-placode cranial nerve for either the diencephalon or mesencephalon. Anat Rec (New Anat) 261:111-125, 2000. Copyright 2000 Wiley-Liss, Inc.

Nothing in Evolution Makes Sense Except in the Light of Genomics: Read-Write Genome Evolution as an Active Biological Process.

PubMed

Shapiro, James A

2016-06-08

The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess "Read-Write Genomes" they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification.

Nothing in Evolution Makes Sense Except in the Light of Genomics: Read–Write Genome Evolution as an Active Biological Process

PubMed Central

Shapiro, James A.

2016-01-01

The 21st century genomics-based analysis of evolutionary variation reveals a number of novel features impossible to predict when Dobzhansky and other evolutionary biologists formulated the neo-Darwinian Modern Synthesis in the middle of the last century. These include three distinct realms of cell evolution; symbiogenetic fusions forming eukaryotic cells with multiple genome compartments; horizontal organelle, virus and DNA transfers; functional organization of proteins as systems of interacting domains subject to rapid evolution by exon shuffling and exonization; distributed genome networks integrated by mobile repetitive regulatory signals; and regulation of multicellular development by non-coding lncRNAs containing repetitive sequence components. Rather than single gene traits, all phenotypes involve coordinated activity by multiple interacting cell molecules. Genomes contain abundant and functional repetitive components in addition to the unique coding sequences envisaged in the early days of molecular biology. Combinatorial coding, plus the biochemical abilities cells possess to rearrange DNA molecules, constitute a powerful toolbox for adaptive genome rewriting. That is, cells possess “Read–Write Genomes” they alter by numerous biochemical processes capable of rapidly restructuring cellular DNA molecules. Rather than viewing genome evolution as a series of accidental modifications, we can now study it as a complex biological process of active self-modification. PMID:27338490

Integration of two RAB5 groups during endosomal transport in plants

PubMed Central

Ebine, Kazuo; Choi, Seung-won; Ichinose, Sakura; Uemura, Tomohiro; Nakano, Akihiko

2018-01-01

RAB5 is a key regulator of endosomal functions in eukaryotic cells. Plants possess two different RAB5 groups, canonical and plant-unique types, which act via unknown counteracting mechanisms. Here, we identified an effector molecule of the plant-unique RAB5 in Arabidopsis thaliana, ARA6, which we designated PLANT-UNIQUE RAB5 EFFECTOR 2 (PUF2). Preferential colocalization with canonical RAB5 on endosomes and genetic interaction analysis indicated that PUF2 coordinates vacuolar transport with canonical RAB5, although PUF2 was identified as an effector of ARA6. Competitive binding of PUF2 with GTP-bound ARA6 and GDP-bound canonical RAB5, together interacting with the shared activating factor VPS9a, showed that ARA6 negatively regulates canonical RAB5-mediated vacuolar transport by titrating PUF2 and VPS9a. These results suggest a unique and unprecedented function for a RAB effector involving the integration of two RAB groups to orchestrate endosomal trafficking in plant cells. PMID:29749929

Nonpeptidic Delta (δ) Opioid Agonists and Antagonists of the Diarylmethylpiperazine Class: What Have We Learned?

NASA Astrophysics Data System (ADS)

Calderon, Silvia N.

The discovery of the selective delta (δ) opioid agonists SNC 80 and BW373U86, which possess a diarylmethylpiperazine structure unique among opioids, represented a major advance in the field of δ-opioid ligands. Extensive research has recently been performed to uncover the structure-activity relationships (SAR) of this class of ligands, thereby providing valuable tools for the pharmacological characterization of the δ opioid receptor. This review focuses on the SAR of this unique series of ligands, and provides an overview of the various chemical routes that have been developed and optimized through the years to allow the syntheses of these ligands on a multigram scale. The search for selective δ opioid agonists and antagonists, as well as for those with mixed opioid agonist properties with potential therapeutic value, continues. Several questions regarding the interaction at the molecular level of diphenylmethylpiperazine derivatives and related analogs with opioid receptors and in particular with the δ opioid system still remain unanswered. Indeed, the development and pharmacological characterization of novel nonpeptidic δ opioid ligands remains an active area of research, as it may provide a better understanding of the role of this receptor in multiple disease states and disorders.

Clastic pipe characteristics and distributions throughout the Colorado Plateau: Implications for paleoenvironment and paleoseismic controls

NASA Astrophysics Data System (ADS)

Wheatley, D. F.; Chan, M. A.; Sprinkel, D. A.

2016-10-01

Clastic pipes occur throughout much of the Phanerozoic strata of the Colorado Plateau and provide a unique opportunity to test the validly of various deformation and triggering mechanism hypotheses in the context of their tectono-stratigraphic and paleoenvironmental settings. Pipes dominantly occur in Jurassic strata and preferentially in eolian (especially interdune), sabkha, and fluvial deposits because these sediments contained interbedded fine-grained and water-saturated, high-porosity, coarse-grained facies. The greatest geographic concentrations of pipes occur in three trends: (1) a northeast trend from the Lake Powell to Moab areas of southern and southeastern Utah, (2) an east-west trend in northern Arizona within and north of the Grand Canyon, and (3) a west-northwest-east-southeast trend along Interstate 40 west of Albuquerque, New Mexico. Many pipes formed due to liquefaction and fluidization and were potentially triggered by seismic activity originating from basement-cored uplifts within the Colorado Plateau, although other trigger mechanisms cannot be completely eliminated. Some breccia pipes within northern Arizona that are rooted in karst are the exception to this interpretation. Pipes possess unique depositional and triggering requirements and thus provide an excellent opportunity to understand the interplay of sedimentology and tectonics within continental systems.

Graphitic carbon nitride based nanocomposites: a review

NASA Astrophysics Data System (ADS)

Zhao, Zaiwang; Sun, Yanjuan; Dong, Fan

2014-11-01

Graphitic carbon nitride (g-C3N4), as an intriguing earth-abundant visible light photocatalyst, possesses a unique two-dimensional structure, excellent chemical stability and tunable electronic structure. Pure g-C3N4 suffers from rapid recombination of photo-generated electron-hole pairs resulting in low photocatalytic activity. Because of the unique electronic structure, the g-C3N4 could act as an eminent candidate for coupling with various functional materials to enhance the performance. According to the discrepancies in the photocatalytic mechanism and process, six primary systems of g-C3N4-based nanocomposites can be classified and summarized: namely, the g-C3N4 based metal-free heterojunction, the g-C3N4/single metal oxide (metal sulfide) heterojunction, g-C3N4/composite oxide, the g-C3N4/halide heterojunction, g-C3N4/noble metal heterostructures, and the g-C3N4 based complex system. Apart from the depiction of the fabrication methods, heterojunction structure and multifunctional application of the g-C3N4-based nanocomposites, we emphasize and elaborate on the underlying mechanisms in the photocatalytic activity enhancement of g-C3N4-based nanocomposites. The unique functions of the p-n junction (semiconductor/semiconductor heterostructures), the Schottky junction (metal/semiconductor heterostructures), the surface plasmon resonance (SPR) effect, photosensitization, superconductivity, etc. are utilized in the photocatalytic processes. Furthermore, the enhanced performance of g-C3N4-based nanocomposites has been widely employed in environmental and energetic applications such as photocatalytic degradation of pollutants, photocatalytic hydrogen generation, carbon dioxide reduction, disinfection, and supercapacitors. This critical review ends with a summary and some perspectives on the challenges and new directions in exploring g-C3N4-based advanced nanomaterials.

New genus, new species of Acanthocephala (Echinorhynchidae) from the Brazilian frog Hylodes phyllodes (Anura: Leptodactylidae).

PubMed

Bursey, Charles R; Vrcibradic, Davor; Hatano, Fabio H; Rocha, Carlos Frederico D

2006-04-01

Anuracanthorhynchus tritaxisentis n. gen., n. sp. from the intestines of the Brazilian frog Hylodes phyllodes (Leptodactylidae) is described and illustrated. Anuracanthorhynchus tritaxisentis n. gen., n. sp., is unique among the echinorhynchid Acanthocephala by possessing a spherical proboscis supporting a small number of hooks of equal size. It is the sixth acanthocephalan species reported from South American anurans.

Long-Term Counterinsurgency Strategy: Maximizing Special Operations and Airpower

DTIC Science & Technology

2010-02-01

operations forces possess a repertoire of capabilities and attributes which impart them with unique strategic utility. “That utility reposes most...flashlight), LTMs are employed in a similar role to cue aircrews equipped with Night Vision Devices (NVDs). Concurrently, employment of small laptop...Special Operations Forces (PSS-SOF) and Precision Fires Image Generator (PFIG) have brought similar benefit to the employment of GPS/INS targeted weapons

Draft Genome Sequence of Mycobacterium chimaera Type Strain Fl-0169.

PubMed

Pfaller, Stacy; Tokarev, Vasily; Kessler, Collin; McLimans, Christopher; Gomez-Alvarez, Vicente; Wright, Justin; King, Dawn; Lamendella, Regina

2017-02-23

We report here the draft genome sequence of the type strain Mycobacterium chimaera Fl-0169, a member of the Mycobacterium avium complex (MAC). M. chimaera Fl-0169 T was isolated from a patient in Italy and is highly similar to strains of M. chimaera isolated in Ireland, although Fl-0169 T possesses unique virulence genes. Copyright © 2017 Pfaller et al.

How Many Jelly Beans Are in the Jar?

ERIC Educational Resources Information Center

Roy, George J.; Hodges, Thomas E.; Graul, LuAnn

2016-01-01

Who will make a better estimate concerning the number of jelly beans in a jar, a single person or a group of people? On one side of the debate is the notion that a person would make a better decision because he or she uses unique knowledge that the group may not possess. On the opposite side of the argument is the claim that because of their…

Marine derived xyloketal derivatives exhibit anti-stress and anti-ageing effects through HSF pathway in Caenorhabditis elegans.

PubMed

Zhou, Jie-Bin; Zheng, Ying-Lin; Zeng, Yi-Xuan; Wang, Jia-Wei; Pei, Zhong; Pang, Ji-Yan

2018-03-25

Ageing is a complex but universal phenomenon that progressively challenges the homeostasis network and finally leads to the dysfunction of organisms and even death. Previous studies demonstrated that xyloketal B and its derivatives, a series of marine novel ketone compounds, possessed unique antioxidative effects on endothelial and neuronal oxidative injuries. In this study, we examined the effects of xyloketal derivatives on extending lifespan and healthspan of Caenorhabditis elegans. The results showed that most selected xyloketals could protect Caenorhabditis elegans against heat stress and extend the lifespan of worms. Compound 15, a benzo-1, 3-oxazine xyloketal derivative, possessed most potent effect in anti-heat stress assay and significantly attenuated ageing-related decrease of pumping and bending of the worms in healthspan assay. In addition, the beneficial effect of 15 was abolished in PS3551 worms, a strain that possesses non-functional heat shock transcription factor-1 (HSF-1). Furthermore, 15 increased the expression of heat shock protein 70 (HSP70), a downstream molecular chaperone of HSF-1. These results indicated that HSF-1 might contribute to the protective effect of this compound in Caenorhabditis elegans ageing. Molecular docking studies suggested that these xyloketal derivatives were bound to the DNA binding domain of HSF-1, promoted the conformation of HSF-1, thus strengthened the interaction between the HSF-1 and related DNA. ALA-67, ASN-74 and LYS-80 of binding region might be the key amino residues during the interaction. Finally, compound 15 could reduce the paralysis of the CL4176 worms, a transgenic strain expressing human Aβ 3-42 under a temperature-inducible system. Collectively, these data indicate that xyloketals have potential implications for further evaluation in anti-ageing studies. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Systematic dissection of phenotypic, functional, and tumorigenic heterogeneity of human prostate cancer cells

PubMed Central

Chao, Hsueh-Ping; Deng, Qu; Jeter, Collene; Liu, Can; Honorio, Sofia; Li, Hangwen; Davis, Tammy; Suraneni, Mahipal; Laffin, Brian; Qin, Jichao; Li, Qiuhui; Yang, Tao; Whitney, Pamela; Shen, Jianjun; Huang, Jiaoti; Tang, Dean G.

2015-01-01

Human cancers are heterogeneous containing stem-like cancer cells operationally defined as cancer stem cells (CSCs) that possess great tumor-initiating and long-term tumor-propagating properties. In this study, we systematically dissect the phenotypic, functional and tumorigenic heterogeneity in human prostate cancer (PCa) using xenograft models and >70 patient tumor samples. In the first part, we further investigate the PSA−/lo PCa cell population, which we have recently shown to harbor self-renewing long-term tumor-propagating cells and present several novel findings. We show that discordant AR and PSA expression in both untreated and castration-resistant PCa (CRPC) results in AR+PSA+, AR+PSA−, AR−PSA−, and AR−PSA+ subtypes of PCa cells that manifest differential sensitivities to therapeutics. We further demonstrate that castration leads to a great enrichment of PSA−/lo PCa cells in both xenograft tumors and CRPC samples and systemic androgen levels dynamically regulate the relative abundance of PSA+ versus PSA−/lo PCa cells that impacts the kinetics of tumor growth. We also present evidence that the PSA−/lo PCa cells possess distinct epigenetic profiles. As the PSA−/lo PCa cell population is heterogeneous, in the second part, we employ two PSA− (Du145 and PC3) and two PSA+ (LAPC9 and LAPC4) PCa models as well as patient tumor cells to further dissect the clonogenic and tumorigenic subsets. We report that different PCa models possess distinct tumorigenic subpopulations that both commonly and uniquely express important signaling pathways that could represent therapeutic targets. Our results have important implications in understanding PCa cell heterogeneity, response to clinical therapeutics, and cellular mechanisms underlying CRPC. PMID:26246472

The SI strain of measles virus derived from a patient with subacute sclerosing panencephalitis possesses typical genome alterations and unique amino acid changes that modulate receptor specificity and reduce membrane fusion activity.

PubMed

Seki, Fumio; Yamada, Kentaro; Nakatsu, Yuichiro; Okamura, Koji; Yanagi, Yusuke; Nakayama, Tetsuo; Komase, Katsuhiro; Takeda, Makoto

2011-11-01

Subacute sclerosing panencephalitis (SSPE) is a fatal sequela associated with measles and is caused by persistent infection of the brain with measles virus (MV). The SI strain was isolated in 1976 from a patient with SSPE and shows neurovirulence in animals. Genome nucleotide sequence analyses showed that the SI strain genome possesses typical genome alterations for SSPE-derived strains, namely, accumulated amino acid substitutions in the M protein and cytoplasmic tail truncation of the F protein. Through the establishment of an efficient reverse genetics system, a recombinant SI strain expressing a green fluorescent protein (rSI-AcGFP) was generated. The infection of various cell types with rSI-AcGFP was evaluated by fluorescence microscopy. rSI-AcGFP exhibited limited syncytium-forming activity and spread poorly in cells. Analyses using a recombinant MV possessing a chimeric genome between those of the SI strain and a wild-type MV strain indicated that the membrane-associated protein genes (M, F, and H) were responsible for the altered growth phenotype of the SI strain. Functional analyses of viral glycoproteins showed that the F protein of the SI strain exhibited reduced fusion activity because of an E300G substitution and that the H protein of the SI strain used CD46 efficiently but used the original MV receptors on immune and epithelial cells poorly because of L482F, S546G, and F555L substitutions. The data obtained in the present study provide a new platform for analyses of SSPE-derived strains as well as a clear example of an SSPE-derived strain that exhibits altered receptor specificity and limited fusion activity.

The SI Strain of Measles Virus Derived from a Patient with Subacute Sclerosing Panencephalitis Possesses Typical Genome Alterations and Unique Amino Acid Changes That Modulate Receptor Specificity and Reduce Membrane Fusion Activity ▿ ‡

PubMed Central

Seki, Fumio; Yamada, Kentaro; Nakatsu, Yuichiro; Okamura, Koji; Yanagi, Yusuke; Nakayama, Tetsuo; Komase, Katsuhiro; Takeda, Makoto

2011-01-01

Subacute sclerosing panencephalitis (SSPE) is a fatal sequela associated with measles and is caused by persistent infection of the brain with measles virus (MV). The SI strain was isolated in 1976 from a patient with SSPE and shows neurovirulence in animals. Genome nucleotide sequence analyses showed that the SI strain genome possesses typical genome alterations for SSPE-derived strains, namely, accumulated amino acid substitutions in the M protein and cytoplasmic tail truncation of the F protein. Through the establishment of an efficient reverse genetics system, a recombinant SI strain expressing a green fluorescent protein (rSI-AcGFP) was generated. The infection of various cell types with rSI-AcGFP was evaluated by fluorescence microscopy. rSI-AcGFP exhibited limited syncytium-forming activity and spread poorly in cells. Analyses using a recombinant MV possessing a chimeric genome between those of the SI strain and a wild-type MV strain indicated that the membrane-associated protein genes (M, F, and H) were responsible for the altered growth phenotype of the SI strain. Functional analyses of viral glycoproteins showed that the F protein of the SI strain exhibited reduced fusion activity because of an E300G substitution and that the H protein of the SI strain used CD46 efficiently but used the original MV receptors on immune and epithelial cells poorly because of L482F, S546G, and F555L substitutions. The data obtained in the present study provide a new platform for analyses of SSPE-derived strains as well as a clear example of an SSPE-derived strain that exhibits altered receptor specificity and limited fusion activity. PMID:21917959

General health risk of periodontal disease.

PubMed

Slots, J; Kamma, J J

2001-12-01

The possibility that periodontal disease might influence the morbidity and mortality of systemic diseases constitutes a research topic of great current interest. Human periodontal disease is associated with a complex microbiota containing approximately 500 microbial taxa and various human viruses, many of which possess significant virulence potential. Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and other periodontopathic bacteria that are unique to the oral cavity and may disseminate to other body sites comprise the best-documented form of dental focal infection. However, systemically healthy individuals seem to be at low risk of acquiring acute non-oral diseases from direct infections by periodontal pathogens. Research data from various laboratories point to periodontal infections as a risk factor for chronic medical disorders, including cardiovascular disease, cerebrovascular accidents and low-birth-weight infants. However, recent epidemiological studies have failed to show a significant relationship between periodontal disease and cardiovascular disease. This review paper evaluates the current status of knowledge on dental focal infection and suggests avenues for further research into the topic of general health risks of periodontal disease.

Valley spin polarization of Tl/Si(111)

NASA Astrophysics Data System (ADS)

Stolwijk, Sebastian D.; Schmidt, Anke B.; Sakamoto, Kazuyuki; Krüger, Peter; Donath, Markus

2017-11-01

The metal/semiconductor hybrid system Tl/Si(111)-(1 ×1 ) exhibits a unique Tl-derived surface state with remarkable properties. It lies within the silicon band gap and forms spin-momentum-locked valleys close to the Fermi energy at the K ¯ and K¯' points. These valleys are completely spin polarized with opposite spin orientation at K ¯ and K¯' and show a giant spin splitting of more than 0.5 eV. We present a detailed preparation study of the surface system and demonstrate that the electronic valleys are extremely robust, surviving exposure to 100 L hydrogen and 500 L oxygen. We investigate the influence of additional Tl atoms on the spin-polarized valleys. By combining photoemission and inverse photoemission, we prove the existence of fully spin-polarized valleys crossing the Fermi level. Moreover, these metallic valleys carry opposite Berry curvature at K ¯ and K¯', very similar to WSe2, promising a large spin Hall effect. Thus, Tl/Si(111)-(1 ×1 ) possesses all necessary key properties for spintronic applications.

Parallel Distractor Rejection as a Binding Mechanism in Search

PubMed Central

Dent, Kevin; Allen, Harriet A.; Braithwaite, Jason J.; Humphreys, Glyn W.

2012-01-01

The relatively common experimental visual search task of finding a red X amongst red O’s and green X’s (conjunction search) presents the visual system with a binding problem. Illusory conjunctions (ICs) of features across objects must be avoided and only features present in the same object bound together. Correct binding into unique objects by the visual system may be promoted, and ICs minimized, by inhibiting the locations of distractors possessing non-target features (e.g., Treisman and Sato, 1990). Such parallel rejection of interfering distractors leaves the target as the only item competing for selection; thus solving the binding problem. In the present article we explore the theoretical and empirical basis of this process of active distractor inhibition in search. Specific experiments that provide strong evidence for a process of active distractor inhibition in search are highlighted. In the final part of the article we consider how distractor inhibition, as defined here, may be realized at a neurophysiological level (Treisman and Sato, 1990). PMID:22908002

Global Regularity and Time Decay for the 2D Magnetohydrodynamic Equations with Fractional Dissipation and Partial Magnetic Diffusion

NASA Astrophysics Data System (ADS)

Dong, Bo-Qing; Jia, Yan; Li, Jingna; Wu, Jiahong

2018-05-01

This paper focuses on a system of the 2D magnetohydrodynamic (MHD) equations with the kinematic dissipation given by the fractional operator (-Δ )^α and the magnetic diffusion by partial Laplacian. We are able to show that this system with any α >0 always possesses a unique global smooth solution when the initial data is sufficiently smooth. In addition, we make a detailed study on the large-time behavior of these smooth solutions and obtain optimal large-time decay rates. Since the magnetic diffusion is only partial here, some classical tools such as the maximal regularity property for the 2D heat operator can no longer be applied. A key observation on the structure of the MHD equations allows us to get around the difficulties due to the lack of full Laplacian magnetic diffusion. The results presented here are the sharpest on the global regularity problem for the 2D MHD equations with only partial magnetic diffusion.

Transient and Big Are Key Features of an Invertebrate T-type Channel (LCav3) from the Central Nervous System of Lymnaea stagnalis*

PubMed Central

Senatore, Adriano; Spafford, J. David

2010-01-01

Here we describe features of the first non-mammalian T-type calcium channel (LCav3) expressed in vitro. This molluscan channel possesses combined biophysical properties that are reminiscent of all mammalian T-type channels. It exhibits T-type features such as “transient” kinetics, but the “tiny” label, usually associated with Ba2+ conductance, is hard to reconcile with the “bigness” of this channel in many respects. LCav3 is 25% larger than any voltage-gated ion channel expressed to date. It codes for a massive, 322-kDa protein that conducts large macroscopic currents in vitro. LCav3 is also the most abundant Ca2+ channel transcript in the snail nervous system. A window current at typical resting potentials appears to be at least as large as that reported for mammalian channels. This distant gene provides a unique perspective to analyze the structural, functional, drug binding, and evolutionary aspects of T-type channels. PMID:20056611

Respiration in spiders (Araneae).

PubMed

Schmitz, Anke

2016-05-01

Spiders (Araneae) are unique regarding their respiratory system: they are the only animal group that breathe simultaneously with lungs and tracheae. Looking at the physiology of respiration the existence of tracheae plays an important role in spiders with a well-developed tracheal system. Other factors as sex, life time, type of prey capture and the high ability to gain energy anaerobically influence the resting and the active metabolic rate intensely. Most spiders have metabolic rates that are much lower than expected from body mass; but especially those with two pairs of lungs. Males normally have higher resting rates than females; spiders that are less evolved and possess a cribellum have lower metabolic rates than higher evolved species. Freely hunting spiders show a higher energy turnover than spiders hunting with a web. Spiders that live longer than 1 year will have lower metabolic rates than those species that die after 1 year in which development and reproduction must be completed. Lower temperatures and starvation, which most spiders can cope with, will decrease the metabolic rate as well.

Opioid receptor probes derived from cycloaddition of the hallucinogen natural product salvinorin A.

PubMed

Lozama, Anthony; Cunningham, Christopher W; Caspers, Michael J; Douglas, Justin T; Dersch, Christina M; Rothman, Richard B; Prisinzano, Thomas E

2011-04-25

As part of our continuing efforts toward more fully understanding the structure-activity relationships of the neoclerodane diterpene salvinorin A, we report the synthesis and biological characterization of unique cycloadducts through [4+2] Diels-Alder cycloaddition. Microwave-assisted methods were developed and successfully employed, aiding in functionalizing the chemically sensitive salvinorin A scaffold. This demonstrates the first reported results for both cycloaddition of the furan ring and functionalization via microwave-assisted methodology of the salvinorin A skeleton. The cycloadducts yielded herein introduce electron-withdrawing substituents and bulky aromatic groups into the C-12 position. Kappa opioid (KOP) receptor space was explored through aromatization of the bent oxanorbornadiene system possessed by the cycloadducts to a planar phenyl ring system. Although dimethyl- and diethylcarboxylate analogues 5 and 6 retain some affinity and selectivity for KOP receptors and are full agonists, their aromatized counterparts 13 and 14 have reduced affinity for KOP receptors. The methods developed herein signify a novel approach toward rapidly probing the structure-activity relationships of furan-containing natural products.

Manufacturing Solid Dosage Forms from Bulk Liquids Using the Fluid-bed Drying Technology.

PubMed

Qi, Jianping; Lu, Y I; Wu, Wei

2015-01-01

Solid dosage forms are better than liquid dosage forms in many ways, such as improved physical and chemical stability, ease of storage and transportation, improved handling properties, and patient compliance. Therefore, it is required to transform dosage forms of liquid origins into solid dosage forms. The functional approaches are to absorb the liquids by solid excipients or through drying. The conventional drying technologies for this purpose include drying by heating, vacuum-, freeze- and spray-drying, etc. Among these drying technologies, fluidbed drying emerges as a new technology that possesses unique advantages. Fluid-bed drying or coating is highly efficient in solvent removal, can be performed at relatively low temperatures, and is a one-step process to manufacture formulations in pellet forms. In this article, the status of the art of manufacturing solid dosage forms from bulk liquids by fluid-bed drying technology was reviewed emphasizing on its application in solid dispersion, inclusion complexes, self-microemulsifying systems, and various nanoscale drug delivery systems.

A Passive System Reliability Analysis for a Station Blackout

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

Brunett, Acacia; Bucknor, Matthew; Grabaskas, David

2015-05-03

The latest iterations of advanced reactor designs have included increased reliance on passive safety systems to maintain plant integrity during unplanned sequences. While these systems are advantageous in reducing the reliance on human intervention and availability of power, the phenomenological foundations on which these systems are built require a novel approach to a reliability assessment. Passive systems possess the unique ability to fail functionally without failing physically, a result of their explicit dependency on existing boundary conditions that drive their operating mode and capacity. Argonne National Laboratory is performing ongoing analyses that demonstrate various methodologies for the characterization of passivemore » system reliability within a probabilistic framework. Two reliability analysis techniques are utilized in this work. The first approach, the Reliability Method for Passive Systems, provides a mechanistic technique employing deterministic models and conventional static event trees. The second approach, a simulation-based technique, utilizes discrete dynamic event trees to treat time- dependent phenomena during scenario evolution. For this demonstration analysis, both reliability assessment techniques are used to analyze an extended station blackout in a pool-type sodium fast reactor (SFR) coupled with a reactor cavity cooling system (RCCS). This work demonstrates the entire process of a passive system reliability analysis, including identification of important parameters and failure metrics, treatment of uncertainties and analysis of results.« less

Cellulosic Nanomaterials in Food and Nutraceutical Applications: A Review.

PubMed

Khan, Avik; Wen, Yangbing; Huq, Tanzina; Ni, Yonghao

2018-01-10

Cellulosic nanomaterials (CNMs) are organic, green nanomaterials that are obtained from renewable sources and possess exceptional mechanical strength and biocompatibility. The associated unique physical and chemical properties have made these nanomaterials an intriguing prospect for various applications including the food and nutraceutical industry. From the immobilization of various bioactive agents and enzymes, emulsion stabilization, direct food additives, to the development of intelligent packaging systems or pathogen or pH detectors, the potential food related applications for CNMs are endless. Over the past decade, there have been several reviews published covering different aspects of cellulosic nanomaterials, such as processing-structure-property relationship, physical and chemical properties, rheology, extraction, nanocomposites, etc. In this critical review, we have discussed and provided a summary of the recent developments in the utilization of cellulosic nanomaterials in applications related to food and nutraceuticals.

DOE interpretations Guide to OSH standards. Update to the Guide

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

Not Available

1994-03-31

Reflecting Secretary O`Leary`s focus on occupational safety and health, the Office of Occupational Safety is pleased to provide you with the latest update to the DOE Interpretations Guide to OSH Standards. This Guide was developed in cooperation with the Occupational Safety and Health Administration, which continued its support during this last revision by facilitating access to the interpretations found on the OSHA Computerized Information System (OCIS). This March 31, 1994 update contains 123 formal interpretation letters written OSHA. As a result of the unique requests received by the 1-800 Response Line, this update also contains 38 interpretations developed by DOE.more » This new occupational safety and health information adds still more important guidance to the four volume reference set that you presently have in your possession.« less

Implications of protein- and Peptide-based nanoparticles as potential vehicles for anticancer drugs.

PubMed

Elzoghby, Ahmed O; Elgohary, Mayada M; Kamel, Nayra M

2015-01-01

Protein-based nanocarriers have gained considerable attention as colloidal carrier systems for the delivery of anticancer drugs. Protein nanocarriers possess various advantages including their low cytotoxicity, abundant renewable sources, high drug-binding capacity, and significant uptake into the targeted tumor cells. Moreover, the unique protein structure offers the possibility of site-specific drug conjugation and tumor targeting using various ligands modifying the surface of protein nanocarriers. In this chapter, we highlight the most important applications of protein nanoparticles (NPs) for the delivery of anticancer drugs. We examine the various techniques that have been utilized for the preparation of anticancer drug-loaded protein NPs. Finally, the current chapter also reviews the major outcomes of the in vitro and in vivo investigations of surface-modified tumor-targeted protein NPs. © 2015 Elsevier Inc. All rights reserved.

Conjugated amplifying polymers for optical sensing applications.

PubMed

Rochat, Sébastien; Swager, Timothy M

2013-06-12

Thanks to their unique optical and electrochemical properties, conjugated polymers have attracted considerable attention over the last two decades and resulted in numerous technological innovations. In particular, their implementation in sensing schemes and devices was widely investigated and produced a multitude of sensory systems and transduction mechanisms. Conjugated polymers possess numerous attractive features that make them particularly suitable for a broad variety of sensing tasks. They display sensory signal amplification (compared to their small-molecule counterparts) and their structures can easily be tailored to adjust solubility, absorption/emission wavelengths, energy offsets for excited state electron transfer, and/or for use in solution or in the solid state. This versatility has made conjugated polymers a fluorescence sensory platform of choice in the recent years. In this review, we highlight a variety of conjugated polymer-based sensory mechanisms together with selected examples from the recent literature.

DOE interpretations Guide to OSH standards. Update to the Guide

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

Not Available

1994-03-31

Reflecting Secretary O`Leary`s focus on occupational safety and health, the Office of Occupational Safety is pleased to provide you with the latest update to the DOE Interpretations Guide to OSH Standards. This Guide was developed in cooperation with the Occupational Safety and Health Administration, which continued it`s support during this last revision by facilitating access to the interpretations found on the OSHA Computerized Information System (OCIS). This March 31, 1994 update contains 123 formal in letter written by OSHA. As a result of the unique requests received by the 1-800 Response Line, this update also contains 38 interpretations developed bymore » DOE. This new occupational safety and health information adds still more important guidance to the four volume reference set that you presently have in your possession.« less

Gauge invariant gluon spin operator for spinless nonlinear wave solutions

NASA Astrophysics Data System (ADS)

Lee, Bum-Hoon; Kim, Youngman; Pak, D. G.; Tsukioka, Takuya; Zhang, P. M.

2017-04-01

We consider nonlinear wave type solutions with intrinsic mass scale parameter and zero spin in a pure SU(2) quantum chromodynamics (QCD). A new stationary solution which can be treated as a system of static Wu-Yang monopole dressed in off-diagonal gluon field is proposed. A remarkable feature of such a solution is that it possesses a finite energy density everywhere. All considered nonlinear wave type solutions have common features: presence of the mass scale parameter, nonvanishing projection of the color fields along the propagation direction and zero spin. The last property requires revision of the gauge invariant definition of the spin density operator which is supposed to produce spin one states for the massless vector gluon field. We construct a gauge invariant definition of the classical gluon spin density operator which is unique and Lorentz frame independent.

Marine natural flavonoids: chemistry and biological activities.

PubMed

Martins, Beatriz T; Correia da Silva, Marta; Pinto, Madalena; Cidade, Honorina; Kijjoa, Anake

2018-05-04

As more than 70% of the world's surface is covered by oceans, marine organisms offer a rich and unlimited resource of structurally diverse bioactive compounds. These organisms have developed unique properties and bioactive compounds that are, in majority of them, unparalleled by their terrestrial counterparts due to the different surrounding ecological systems. Marine flavonoids have been extensively studied in the last decades due to a growing interest concerning their promising biological/pharmacological activities. The most common classes of marine flavonoids are flavones and flavonols, which are mostly isolated from marine plants. Although most of flavonoids are hydroxylated and methoxylated, some marine flavonoids possess an unusual substitution pattern, not commonly found in terrestrial organisms, namely the presence of sulphate, chlorine, and amino groups. This review presents, for the first time in a systematic way, the structure, natural occurrence, and biological activities of marine flavonoids.

Sales skills for health-care professionals: the emotional side of sales.

PubMed

Nigon, D L

2001-01-01

Health-care sales continues to be an area of opportunity for many laboratory professionals. For those who possess the necessary skills and the desire to enthusiastically embrace the unique challenges of a sales career, a new CLMA publication by CLMR contributor Donna L. Nigon, MT(ASCP), titled Sales Skills for Health-Care Professionals, will provide the knowledge of sales structure and techniques needed to succeed. This Sales Skills excerpt, "The Emotional Side of Sales," describes many of the emotional aspects of sales and selling, including how to handle the transition from a technical or medical role to that of sales representative, relationship building, maintaining personal and professional support systems, dealing with rejection, avoiding burnout, time management, and customer concerns. For more information about this book, please see the order form that accompanies this excerpt, or visit www.clma.org.

A Review: Enhanced Anodes of Li/Na-Ion Batteries Based on Yolk-Shell Structured Nanomaterials

NASA Astrophysics Data System (ADS)

Wu, Cuo; Tong, Xin; Ai, Yuanfei; Liu, De-Sheng; Yu, Peng; Wu, Jiang; Wang, Zhiming M.

2018-09-01

Lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) have received much attention in energy storage system. In particular, among the great efforts on enhancing the performance of LIBs and SIBs, yolk-shell (YS) structured materials have emerged as a promising strategy toward improving lithium and sodium storage. YS structures possess unique interior void space, large surface area and short diffusion distance, which can solve the problems of volume expansion and aggregation of anode materials, thus enhancing the performance of LIBs and SIBs. In this review, we present a brief overview of recent advances in the novel YS structures of spheres, polyhedrons and rods with controllable morphology and compositions. Enhanced electrochemical performance of LIBs and SIBs based on these novel YS structured anode materials was discussed in detail. [Figure not available: see fulltext.

What do we really know about the role of microorganisms in iron sulfide mineral formation?

USGS Publications Warehouse

Picard, Aude A.; Gartman, Amy; Girguis, Peter R.

2016-01-01

Iron sulfide mineralization in low-temperature systems is a result of biotic and abiotic processes, though the delineation between these two modes of formation is not always straightforward. Here we review the role of microorganisms in the precipitation of extracellular iron sulfide minerals. We summarize the evidence that links sulfur-metabolizing microorganisms and sulfide minerals in nature and we present a critical overview of laboratory-based studies of the nucleation and growth of iron sulfide minerals in microbial cultures. We discuss whether biologically derived minerals are distinguishable from abiotic minerals, possessing attributes that are uniquely diagnostic of biomineralization. These inquiries have revealed the need for additional thorough, mechanistic and high-resolution studies to understand microbially mediated formation of a variety of sulfide minerals across a range of natural environments.

The Hoiamides, Structurally Intriguing Neurotoxic Lipopeptides from Papua New Guinea Marine Cyanobacteria

PubMed Central

Choi, Hyukjae; Pereira, Alban R.; Cao, Zhengyu; Shuman, Cynthia F.; Engene, Niclas; Byrum, Tara; Matainaho, Teatulohi; Murray, Thomas F.; Mangoni, Alfonso; Gerwick, William H.

2011-01-01

Two related peptide metabolites, one a cyclic depsipeptide, hoiamide B (2), and the other a linear lipopeptide, hoiamide C (3), were isolated from two different collections of marine cyanobacteria obtained in Papua New Guinea. Their structures were elucidated by combining various techniques in spectroscopy, chromatography and synthetic chemistry. Both metabolites belong to the unique hoiamide structural class, characterized by possessing an acetate extended and S-adenosyl methionine modified isoleucine unit, a central triheterocyclic system comprised of two α-methylated thiazolines and one thiazole, as well as a highly oxygenated and methylated C-15 polyketide unit. In neocortical neurons, the cyclic depsipeptide 2 stimulated sodium influx and suppressed spontaneous Ca2+ oscillations with EC50 values of 3.9 μM and 79.8 nM, respectively, while 3 had no significant effects in these assays. PMID:20687534

Behaviour and design considerations for continuous flow closed-open-closed liquid microchannels.

PubMed

Melin, Jessica; van der Wijngaart, Wouter; Stemme, Göran

2005-06-01

This paper introduces a method of combining open and closed microchannels in a single component in a novel way which couples the benefits of both open and closed microfluidic systems and introduces interesting on-chip microfluidic behaviour. Fluid behaviour in such a component, based on continuous pressure driven flow and surface tension, is discussed in terms of cross sectional flow behaviour, robustness, flow-pressure performance, and its application to microfluidic interfacing. The closed-open-closed microchannel possesses the versatility of upstream and downstream closed microfluidics along with open fluidic direct access. The device has the advantage of eliminating gas bubbles present upstream when these enter the open channel section. The unique behaviour of this device opens the door to applications including direct liquid sample interfacing without the need for additional and bulky sample tubing.

Binding of carboxylate and trimethylammonium salts to octa-acid and TEMOA deep-cavity cavitands

NASA Astrophysics Data System (ADS)

Sullivan, Matthew R.; Sokkalingam, Punidha; Nguyen, Thong; Donahue, James P.; Gibb, Bruce C.

2017-01-01

In participation of the fifth statistical assessment of modeling of proteins and ligands (SAMPL5), the strength of association of six guests ( 3- 8) to two hosts ( 1 and 2) were measured by 1H NMR and ITC. Each host possessed a unique and well-defined binding pocket, whilst the wide array of amphiphilic guests possessed binding moieties that included: a terminal alkyne, nitro-arene, alkyl halide and cyano-arene groups. Solubilizing head groups for the guests included both positively charged trimethylammonium and negatively charged carboxylate functionality. Measured association constants ( K a ) covered five orders of magnitude, ranging from 56 M-1 for guest 6 binding with host 2 up to 7.43 × 106 M-1 for guest 6 binding to host 1.

Nanodiamonds as platforms for biology and medicine.

PubMed

Man, Han B; Ho, Dean

2013-02-01

Nanoparticles possess a wide range of exceptional properties applicable to biology and medicine. In particular, nanodiamonds (NDs) are being studied extensively because they possess unique characteristics that make them suitable as platforms for diagnostics and therapeutics. This carbon-based material (2-8 nm) is medically relevant because it unites several key properties necessary for clinical applications, such as stability and compatibility in biological environments, and scalability in production. Research by the Ho group and others has yielded ND particles with a variety of capabilities ranging from delivery of chemotherapeutic drugs to targeted labeling and uptake studies. In addition, encouraging new findings have demonstrated the ability for NDs to effectively treat chemoresistant tumors in vivo. In this review, we highlight the progress made toward bringing nanodiamonds from the bench to the bedside.

Haptic control of a pneumatic muscle actuator to provide resistance for simulated isokinetic exercise; part II: control development and testing.

PubMed

Hall, Kara L; Phillips, Chandler A; Reynolds, David B; Mohler, Stanley R; Rogers, Dana B; Neidhard-Doll, Amy T

2015-01-01

Pneumatic muscle actuators (PMAs) have a high power to weight ratio and possess unique characteristics which make them ideal actuators for applications involving human interaction. PMAs are difficult to control due to nonlinear dynamics, presenting challenges in system implementation. Despite these challenges, PMAs have great potential as a source of resistance for strength training and rehabilitation. The objective of this work was to control a PMA for use in isokinetic exercise, potentially benefiting anyone in need of optimal strength training through a joint's range of motion. The controller, based on an inverse three-element phenomenological model and adaptive nonlinear control, allows the system to operate as a type of haptic device. A human quadriceps dynamic simulator was developed (as described in Part I of this work) so that control effectiveness and accommodation could be tested prior to human implementation. Tracking error results indicate that the control system is effective at producing PMA displacement and resistance necessary for a scaled, simulated neuromuscular actuator to maintain low-velocity isokinetic movement during simulated concentric and eccentric knee extension.

PTFE-based microreactor system for the continuous synthesis of full-visible-spectrum emitting cesium lead halide perovskite nanocrystals.

PubMed

Zhang, Chengxi; Luan, Weiling; Yin, Yuhang; Yang, Fuqian

2017-01-01

Colloidal perovskite nanocrystals comprised of all inorganic cesium lead halide (CsPbX 3 , X = Cl, Br, I or a mixture thereof) have potential as optical gain materials due to their high luminescence efficiency. In this work, cesium lead halide nanocrystals are continuously synthesized via a microreactor system consisting of poly(tetrafluoroethylene) (PTFE) capillaries. The synthesized nanocrystals possess excellent optical properties, including a full width at half maximum of 19-35 nm, high fluorescence quantum yield of 47.8-90.55%, and photoluminescence emission in the range of 450-700 nm. For the same precursor concentrations, the photoluminescence emission peak generally increases with increasing reaction temperature, revealing a controllable temperature effect on the photoluminescence characteristics of the synthesized nanocrystals. For quantum dots synthesized with a Br/I ratio of 1:3, a slight blue shift was observed for reaction temperatures greater than 100 °C. This PTFE-based microreactor system provides the unique capability of continuously synthesizing high-quality perovskite nanocrystals that emit over the full visible spectrum with applications ranging from displays and optoelectronic devices.

PTFE-based microreactor system for the continuous synthesis of full-visible-spectrum emitting cesium lead halide perovskite nanocrystals

PubMed Central

Zhang, Chengxi; Yin, Yuhang

2017-01-01

Colloidal perovskite nanocrystals comprised of all inorganic cesium lead halide (CsPbX3, X = Cl, Br, I or a mixture thereof) have potential as optical gain materials due to their high luminescence efficiency. In this work, cesium lead halide nanocrystals are continuously synthesized via a microreactor system consisting of poly(tetrafluoroethylene) (PTFE) capillaries. The synthesized nanocrystals possess excellent optical properties, including a full width at half maximum of 19–35 nm, high fluorescence quantum yield of 47.8–90.55%, and photoluminescence emission in the range of 450–700 nm. For the same precursor concentrations, the photoluminescence emission peak generally increases with increasing reaction temperature, revealing a controllable temperature effect on the photoluminescence characteristics of the synthesized nanocrystals. For quantum dots synthesized with a Br/I ratio of 1:3, a slight blue shift was observed for reaction temperatures greater than 100 °C. This PTFE-based microreactor system provides the unique capability of continuously synthesizing high-quality perovskite nanocrystals that emit over the full visible spectrum with applications ranging from displays and optoelectronic devices. PMID:29259867

A dynamic in vivo-like organotypic blood-brain barrier model to probe metastatic brain tumors

NASA Astrophysics Data System (ADS)

Xu, Hui; Li, Zhongyu; Yu, Yue; Sizdahkhani, Saman; Ho, Winson S.; Yin, Fangchao; Wang, Li; Zhu, Guoli; Zhang, Min; Jiang, Lei; Zhuang, Zhengping; Qin, Jianhua

2016-11-01

The blood-brain barrier (BBB) restricts the uptake of many neuro-therapeutic molecules, presenting a formidable hurdle to drug development in brain diseases. We proposed a new and dynamic in vivo-like three-dimensional microfluidic system that replicates the key structural, functional and mechanical properties of the blood-brain barrier in vivo. Multiple factors in this system work synergistically to accentuate BBB-specific attributes-permitting the analysis of complex organ-level responses in both normal and pathological microenvironments in brain tumors. The complex BBB microenvironment is reproduced in this system via physical cell-cell interaction, vascular mechanical cues and cell migration. This model possesses the unique capability to examine brain metastasis of human lung, breast and melanoma cells and their therapeutic responses to chemotherapy. The results suggest that the interactions between cancer cells and astrocytes in BBB microenvironment might affect the ability of malignant brain tumors to traverse between brain and vascular compartments. Furthermore, quantification of spatially resolved barrier functions exists within a single assay, providing a versatile and valuable platform for pharmaceutical development, drug testing and neuroscientific research.

Dangerous mating systems: signal complexity, signal content and neural capacity in spiders.

PubMed

Herberstein, M E; Wignall, A E; Hebets, E A; Schneider, J M

2014-10-01

Spiders are highly efficient predators in possession of exquisite sensory capacities for ambushing prey, combined with machinery for launching rapid and determined attacks. As a consequence, any sexually motivated approach carries a risk of ending up as prey rather than as a mate. Sexual selection has shaped courtship to effectively communicate the presence, identity, motivation and/or quality of potential mates, which help ameliorate these risks. Spiders communicate this information via several sensory channels, including mechanical (e.g. vibrational), visual and/or chemical, with examples of multimodal signalling beginning to emerge in the literature. The diverse environments that spiders inhabit have further shaped courtship content and form. While our understanding of spider neurobiology remains in its infancy, recent studies are highlighting the unique and considerable capacities of spiders to process and respond to complex sexual signals. As a result, the dangerous mating systems of spiders are providing important insights into how ecology shapes the evolution of communication systems, with future work offering the potential to link this complex communication with its neural processes. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reasoning about Codata

NASA Astrophysics Data System (ADS)

Hinze, Ralf

Programmers happily use induction to prove properties of recursive programs. To show properties of corecursive programs they employ coinduction, but perhaps less enthusiastically. Coinduction is often considered a rather low-level proof method, in particular, as it departs quite radically from equational reasoning. Corecursive programs are conveniently defined using recursion equations. Suitably restricted, these equations possess unique solutions. Uniqueness gives rise to a simple and attractive proof technique, which essentially brings equational reasoning to the coworld. We illustrate the approach using two major examples: streams and infinite binary trees. Both coinductive types exhibit a rich structure: they are applicative functors or idioms, and they can be seen as memo-tables or tabulations. We show that definitions and calculations benefit immensely from this additional structure.

The rights of man and animal experimentation.

PubMed Central

Martin, J

1990-01-01

Since emotions give contradictory signals about animal experimentation in medical science, man's relationship to animals must be based upon reason. Thomas Aquinas argues that man is essentially different from animals because man's intellectual processes show evidence of an abstract mechanism not possessed by animals. Man's rights arise in association with this essential difference. The consequence is that only man possesses true rights by Aquinas's definition; animals have them only by analogy. However, cruelty to animals is illicit and they should be protected, principally not because they have rights, but because he who is cruel to animals is more likely to be cruel to his fellowman. If there is a need for animal experimentation in science for the good of man, this approach gives philosophical justification for experimentation, since man's well-being must come before that of animals because of his unique possession of rights. However, those experiments should be carried out in the kindest way possible, to promote kindness towards man. To see man as solely part of a biological continuum in competition for rights with those beings close to him biologically, detracts from man's dignity. PMID:2135948

Multi-tip nano-prisms: Controlled growth and emission enhancement properties

NASA Astrophysics Data System (ADS)

Liu, Ming; Meng, Cong; Xue, Zheng-Hong; Xiong, Xiang; Shu, Da-Jun; Peng, Ru-Wen; Wu, Qiang; Hu, Zheng; Wang, Mu

2013-10-01

We report here the experimental observations that the tip topography of ZnO nano-prisms sensitively depends on the percentage of oxygen in the flux of the carrying gas in vapor growth. At a relatively high oxygen concentration, a number of thin filaments can be nucleated atop nano-prisms, forming a unique fish-spear-like multi-tip morphology. The length and density of the “spear tines” depend on the flux of the carrying gas. The field emission properties of the nanorod array with different tip morphology are investigated. The structures with longer and denser spear tines possess lower turn-on electric field and higher electric current density. The cathodoluminescence properties of the ZnO nano-prisms have also been studied. The luminescence related to defects in multi-tip nano-prisms possesses the strongest intensity, and the nanorod without any tine structure possesses the lowest defect luminescence intensity. The intrinsic luminescence of ZnO around 385 nm, however, has the opposite tendency. We suggest that our observation is inspiring in optimizing the emission properties of the nanowire devices.

Comparison of α-glucosyl hesperidin of citrus fruits and epigallocatechin gallate of green tea on the Loss of Rotavirus Infectivity in Cell Culture.

PubMed

Lipson, Steven M; Ozen, Fatma S; Louis, Samantha; Karthikeyan, Laina

2015-01-01

A number of secondary plant metabolites (e.g., flavonoids) possess antiviral/antimicrobial activity. Most flavonoids, however, are difficult to study, as they are immiscible in water-based systems. The relatively new semisynthetic α-glucosyl hesperitin (GH), and the natural plant product epigallocatechin gallate (EGCG) are unique among most flavonoids, as these flavonoids are highly soluble. The antiviral activity of these plant metabolites were investigated using the rotavirus as a model enteric virus system. Direct loss of virus structural integrity in cell-free suspension and titration of amplified RTV in host cell cultures was measured by a quantitative enzyme-linked immunosorbent assay (qEIA). After 30 min. 100 × 10(3) μg/ml GH reduced RTV antigen levels by ca. 90%. The same compound reduced infectivity (replication in cell culture) by a similar order of magnitude 3 to 4 days post inoculation. After 3 days in culture, EGCG concentrations of 80, 160, and 320 μg/ml reduced RTV infectivity titer levels to ca. 50, 20, and 15% of the control, respectively. Loss of RTV infectivity titers occurred following viral treatment by parallel testing of both GH and EGCG, with the latter, markedly more effective. Cytotoxicity testing showed no adverse effects by the phenolic concentrations used in this study. The unique chemical structure of each flavonoid rather than each phenolic's inherent solubility may be ascribed to those marked differences between each molecule's antiviral (anti-RTV) effects. The solubility of EGCG and GH obviated our need to use potentially confounding or obfuscating carrier molecules (e.g., methanol, ethanol, DMSO) denoting our use of a pure system environ. Our work further denotes the need to address the unique chemical nature of secondary plant metabolites before any broad generalizations in flavonoid (antiviral) activity may be proposed.

Novel chemistry of invasive plants: exotic species have more unique metabolomic profiles than native congeners.

PubMed

Macel, Mirka; de Vos, Ric C H; Jansen, Jeroen J; van der Putten, Wim H; van Dam, Nicole M

2014-07-01

It is often assumed that exotic plants can become invasive when they possess novel secondary chemistry compared with native plants in the introduced range. Using untargeted metabolomic fingerprinting, we compared a broad range of metabolites of six successful exotic plant species and their native congeners of the family Asteraceae. Our results showed that plant chemistry is highly species-specific and diverse among both exotic and native species. Nonetheless, the exotic species had on average a higher total number of metabolites and more species-unique metabolites compared with their native congeners. Herbivory led to an overall increase in metabolites in all plant species. Generalist herbivore performance was lower on most of the exotic species compared with the native species. We conclude that high chemical diversity and large phytochemical uniqueness of the exotic species could be indicative of biological invasion potential.

Scleroderma Autoantigens Are Uniquely Fragmented by Metal-catalyzed Oxidation Reactions: Implications for Pathogenesis

PubMed Central

Casciola-Rosen, Livia; Wigley, Fredrick; Rosen, Antony

1997-01-01

The observation that revelation of immunocryptic epitopes in self antigens may initiate the autoimmune response has prompted the search for processes which induce novel fragmentation of autoantigens as potential initiators of autoimmunity. The reversible ischemia reperfusion which characterizes scleroderma has focused attention on reactive oxygen species as molecules which might induce autoantigen fragmentation. We demonstrate that several of the autoantigens targeted in diffuse scleroderma are uniquely susceptible to cleavage by reactive oxygen species, in a metal-dependent manner. Multiple features of the fragmentation reaction and its inhibition indicate that these autoantigens possess metal-binding sites, which focus metal-catalyzed oxidation reactions (and consequent fragmentation) to specific regions of the antigens. These data suggest that the autoantibody response in scleroderma is the immune marker of unique protein fragmentation, induced by ischemia reperfusion in the presence of appropriate metals, and focus attention on abnormal metal status as a potential pathogenic principle in this disease. PMID:8996243

A MEMS-based, wireless, biometric-like security system

NASA Astrophysics Data System (ADS)

Cross, Joshua D.; Schneiter, John L.; Leiby, Grant A.; McCarter, Steven; Smith, Jeremiah; Budka, Thomas P.

2010-04-01

We present a system for secure identification applications that is based upon biometric-like MEMS chips. The MEMS chips have unique frequency signatures resulting from fabrication process variations. The MEMS chips possess something analogous to a "voiceprint". The chips are vacuum encapsulated, rugged, and suitable for low-cost, highvolume mass production. Furthermore, the fabrication process is fully integrated with standard CMOS fabrication methods. One is able to operate the MEMS-based identification system similarly to a conventional RFID system: the reader (essentially a custom network analyzer) detects the power reflected across a frequency spectrum from a MEMS chip in its vicinity. We demonstrate prototype "tags" - MEMS chips placed on a credit card-like substrate - to show how the system could be used in standard identification or authentication applications. We have integrated power scavenging to provide DC bias for the MEMS chips through the use of a 915 MHz source in the reader and a RF-DC conversion circuit on the tag. The system enables a high level of protection against typical RFID hacking attacks. There is no need for signal encryption, so back-end infrastructure is minimal. We believe this system would make a viable low-cost, high-security system for a variety of identification and authentication applications.

Two ancient bacterial-like PPP family phosphatases from Arabidopsis are highly conserved plant proteins that possess unique properties.

PubMed

Uhrig, R Glen; Moorhead, Greg B

2011-12-01

Protein phosphorylation, catalyzed by the opposing actions of protein kinases and phosphatases, is a cornerstone of cellular signaling and regulation. Since their discovery, protein phosphatases have emerged as highly regulated enzymes with specificity that rivals their counteracting kinase partners. However, despite years of focused characterization in mammalian and yeast systems, many protein phosphatases in plants remain poorly or incompletely characterized. Here, we describe a bioinformatic, biochemical, and cellular examination of an ancient, Bacterial-like subclass of the phosphoprotein phosphatase (PPP) family designated the Shewanella-like protein phosphatases (SLP phosphatases). The SLP phosphatase subcluster is highly conserved in all plants, mosses, and green algae, with members also found in select fungi, protists, and bacteria. As in other plant species, the nucleus-encoded Arabidopsis (Arabidopsis thaliana) SLP phosphatases (AtSLP1 and AtSLP2) lack genetic redundancy and phylogenetically cluster into two distinct groups that maintain different subcellular localizations, with SLP1 being chloroplastic and SLP2 being cytosolic. Using heterologously expressed and purified protein, the enzymatic properties of both AtSLP1 and AtSLP2 were examined, revealing unique metal cation preferences in addition to a complete insensitivity to the classic serine/threonine PPP protein phosphatase inhibitors okadaic acid and microcystin. The unique properties and high conservation of the plant SLP phosphatases, coupled to their exclusion from animals, red algae, cyanobacteria, archaea, and most bacteria, render understanding the function(s) of this new subclass of PPP family protein phosphatases of particular interest.

Enzymes from solvent-tolerant microbes: useful biocatalysts for non-aqueous enzymology.

PubMed

Gupta, Anshu; Khare, S K

2009-01-01

Solvent-tolerant microbes are a newly emerging class that possesses the unique ability to thrive in the presence of organic solvents. Their enzymes adapted to mediate cellular and metabolic processes in a solvent-rich environment and are logically stable in the presence of organic solvents. Enzyme catalysis in non-aqueous/low-water media is finding increasing applications for the synthesis of industrially important products, namely peptides, esters, and other trans-esterification products. Solvent stability, however, remains a prerequisite for employing enzymes in non-aqueous systems. Enzymes, in general, get inactivated or give very low rates of reaction in non-aqueous media. Thus, early efforts, and even some recent ones, have aimed at stabilization of enzymes in organic media by immobilization, surface modifications, mutagenesis, and protein engineering. Enzymes from solvent-tolerant microbes appear to be the choicest source for studying solvent-stable enzymes because of their unique ability to survive in the presence of a range of organic solvents. These bacteria circumvent the solvent's toxic effects by virtue of various adaptations, e.g. at the level of the cytoplasmic membrane, by degradation and transformation of solvents, and by active excretion of solvents. The recent screening of these exotic microbes has generated some naturally solvent-stable proteases, lipases, cholesterol oxidase, cholesterol esterase, cyclodextrin glucanotransferase, and other important enzymes. The unique properties of these novel biocatalysts have great potential for applications in non-aqueous enzymology for a range of industrial processes.

Characterization of local goat breeds using RAP-DNA markers

NASA Astrophysics Data System (ADS)

Al-Barzinji, Yousif M. S.; Hamad, Aram O.

2017-09-01

The present study was conducted on different colors of local goat breeds. A number of 216 does were sampled from the seven groups. Genomic DNA was extracted from the blood samples. From the twenty used RAPD primers 12 of them were amplified, and presence of bands. The total fragment number of 12 primers over all the goat breed samples was 485 fragments. Out of the 485 fragments, 90 of them were Polymorphic fragments numbers (PFN). From all bands obtained, 20 of them possessed unique bands. The highest unique band was found in locus RAP 6 which has 4 unique bands, three of them in the Maraz Brown and one in the local Koor. Nei's gene diversity and Shanon's information index in this study were averaged 0.38 and 0.60, respectively. The genetic distance among several goat breeds ranged from 9.11 to 43.33%. The highest genetic distance 43.33% recorded between Maraz goat and other goat breeds and between local Koor and other goat (except Maraz goats) breeds (37.79%). However, the lowest genetic distance recorded between local white and Pnok. The distance between (local Black and Pnok) and (local Black and local white) was 22.75%. In conclusions, the high distance among these goat breeds, polymorphism and high numbers of unique bands found in present study indicates that these goat breeds have the required amount of genetic variation to made genetic improvement. This study helps us to clarify the image of the genetic diversity of the local goat breeds and the breeders can used it for mating system when need to make the crossing among these goat breeds.

A comparison of postnatal arterial patterns in a growth series of giraffe (Artiodactyla: Giraffa camelopardalis)

PubMed Central

Gignac, Paul M.; Hieronymus, Tobin L.; Witmer, Lawrence M.

2016-01-01

Nearly all living artiodactyls (even-toed ungulates) possess a derived cranial arterial pattern that is highly distinctive from most other mammals. Foremost among a suite of atypical arterial configurations is the functional and anatomical replacement of the internal carotid artery with an extensive, subdural arterial meshwork called the carotid rete. This interdigitating network branches from the maxillary artery and is housed within the cavernous venous sinus. As the cavernous sinus receives cooled blood draining from the nasal mucosa, heat rapidly dissipates across the high surface area of the rete to be carried away from the brain by the venous system. This combination yields one of the most effective mechanisms of selective brain cooling. Although arterial development begins from the same embryonic scaffolding typical of mammals, possession of a rete is typically accompanied by obliteration of the internal carotid artery. Among taxa with available ontogenetic data, the point at which the internal carotid obliterates is variable throughout development. In small-bodied artiodactyls, the internal carotid typically obliterates prior to parturition, but in larger species, the vessel may remain patent for several years. In this study, we use digital anatomical data collection methods to describe the cranial arterial patterns for a growth series of giraffe (Giraffa camelopardalis), from parturition to senescence. Giraffes, in particular, have unique cardiovascular demands and adaptations owing to their exceptional body form and may not adhere to previously documented stages of cranial arterial development. We find the carotid arterial system to be conserved between developmental stages and that obliteration of the giraffe internal carotid artery occurs prior to parturition. PMID:26925324

A comparison of postnatal arterial patterns in a growth series of giraffe (Artiodactyla: Giraffa camelopardalis).

PubMed

O'Brien, Haley D; Gignac, Paul M; Hieronymus, Tobin L; Witmer, Lawrence M

2016-01-01

Nearly all living artiodactyls (even-toed ungulates) possess a derived cranial arterial pattern that is highly distinctive from most other mammals. Foremost among a suite of atypical arterial configurations is the functional and anatomical replacement of the internal carotid artery with an extensive, subdural arterial meshwork called the carotid rete. This interdigitating network branches from the maxillary artery and is housed within the cavernous venous sinus. As the cavernous sinus receives cooled blood draining from the nasal mucosa, heat rapidly dissipates across the high surface area of the rete to be carried away from the brain by the venous system. This combination yields one of the most effective mechanisms of selective brain cooling. Although arterial development begins from the same embryonic scaffolding typical of mammals, possession of a rete is typically accompanied by obliteration of the internal carotid artery. Among taxa with available ontogenetic data, the point at which the internal carotid obliterates is variable throughout development. In small-bodied artiodactyls, the internal carotid typically obliterates prior to parturition, but in larger species, the vessel may remain patent for several years. In this study, we use digital anatomical data collection methods to describe the cranial arterial patterns for a growth series of giraffe (Giraffa camelopardalis), from parturition to senescence. Giraffes, in particular, have unique cardiovascular demands and adaptations owing to their exceptional body form and may not adhere to previously documented stages of cranial arterial development. We find the carotid arterial system to be conserved between developmental stages and that obliteration of the giraffe internal carotid artery occurs prior to parturition.

50 CFR 27.82 - Possession and delivery of controlled substances.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Possession and delivery of controlled... THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: Personal Conduct § 27.82 Possession and delivery of controlled substances. (a) Definitions for the purpose...

50 CFR 27.82 - Possession and delivery of controlled substances.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Possession and delivery of controlled... THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: Personal Conduct § 27.82 Possession and delivery of controlled substances. (a) Definitions for the purpose...

50 CFR 27.82 - Possession and delivery of controlled substances.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Possession and delivery of controlled... THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: Personal Conduct § 27.82 Possession and delivery of controlled substances. (a) Definitions for the purpose...

50 CFR 27.82 - Possession and delivery of controlled substances.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Possession and delivery of controlled... THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: Personal Conduct § 27.82 Possession and delivery of controlled substances. (a) Definitions for the purpose...

50 CFR 27.82 - Possession and delivery of controlled substances.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Possession and delivery of controlled... THE INTERIOR (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM PROHIBITED ACTS Disturbing Violations: Personal Conduct § 27.82 Possession and delivery of controlled substances. (a) Definitions for the purpose...

Virgatolides A-C, benzannulated spiroketals from the plant endophytic fungus Pestalotiopsis virgatula.

PubMed

Li, Jian; Li, Li; Si, Yikang; Jiang, Xuejun; Guo, Liangdong; Che, Yongsheng

2011-05-20

Virgatolides A-C (1-3), unique metabolites with a 3',4',5',6'-tetrahydrospiro[chroman-2,2'-pyran] core, were isolated from cultures of the plant endophytic fungus Pestalotiopsis virgatula. Compounds 1-3 possess two previously undescribed skeletons originating from a benzannulated 6,6-spiroketal and one (2 and 3) and two (1) γ-lactone units, respectively. The structure of 1 was secured by X-ray crystallography.

Nanochannel Electroporation as a Platform for Living Cell Interrogation in Acute Myeloid Leukemia.

PubMed

Zhao, Xi; Huang, Xiaomeng; Wang, Xinmei; Wu, Yun; Eisfeld, Ann-Kathrin; Schwind, Sebastian; Gallego-Perez, Daniel; Boukany, Pouyan E; Marcucci, Guido I; Lee, Ly James

2015-12-01

A living cell interrogation platform based on nanochannel electroporation is demonstrated with analysis of RNAs in single cells. This minimally invasive process is based on individual cells and allows both multi-target analysis and stimulus-response analysis by sequential deliveries. The unique platform possesses a great potential to the comprehensive and lysis-free nucleic acid analysis on rare or hard-to-transfect cells.

Global charges of stationary non-Abelian black holes.

PubMed

Kleihaus, Burkhard; Kunz, Jutta; Navarro-Lérida, Francisco

2003-05-02

We consider stationary axially symmetric black holes in SU(2) Einstein-Yang-Mills-dilaton theory. We present a mass formula for these stationary non-Abelian black holes, which also holds for Abelian black holes. The presence of the dilaton field allows for rotating black holes, which possess nontrivial electric and magnetic gauge fields, but do not carry a non-Abelian charge. We further present a new uniqueness conjecture.

Honoring Counterstories: Utilizing Digital Storytelling in the Culturally Responsive Classroom to Investigate the Community Cultural Wealth and Resiliency of Students with Limited or Interrupted Formal Education (SLIFE)

ERIC Educational Resources Information Center

Porter, Christina M.

2013-01-01

This ethnography seeks to identify the strengths that students with limited or interrupted formal education (SLIFE), a unique subpopulation of English Language Learners (ELLs), possess and explore how those strengths may be utilized in the secondary classroom. This research aims to shift the focus from "eliminating deficits" to working…

Canadian Light Infantry in Adaptive Dispersed Operations

DTIC Science & Technology

2012-05-17

participated directly or indirectly under the leadership of Combined Joint Task Force (CJTF) MOUNTAIN, which was mostly built around the 10th Mountain...unique and possesses its own characteristics. It has its own ethic which is obtained from its distinctive tactical style , special attitude toward the...it is not organization that determines their light nature but their characteristics and fighting style . He added: “The historical tendency for light

Canadian Light Infantry in Adaptive Dispersed Operations

DTIC Science & Technology

2012-05-22

participated directly or indirectly under the leadership of Combined Joint Task Force (CJTF) MOUNTAIN, which was mostly built around the 10th Mountain...unique and possesses its own characteristics. It has its own ethic which is obtained from its distinctive tactical style , special attitude toward the...it is not organization that determines their light nature but their characteristics and fighting style . He added: “The historical tendency for light

Ordered mesoporous ferrosilicate materials with highly dispersed iron oxide nanoparticles and investigation of their unique magnetic properties.

PubMed

Srinivasu, Pavuluri; Suresh, Koppoju; Datt, Gopal; Abhayankar, Ashutosh C; Rao, Pothuraju Nageswara; Lakshmi Kantam, Mannepalli; Bhargava, Suresh K; Tang, Jing; Yamauchi, Yusuke

2014-11-07

Ordered mesoporous ferrosilicate materials with highly dispersed iron oxide nanoparticles are directly synthesized through a hydrothermal approach under acidic conditions. The obtained samples possess a high surface area (up to 1236 m(2) g(-1)) and a large pore volume (up to 1.1 cm(3) g(-1)). By changing the amount of iron content, the magnetic properties can be tuned.

Fabrication of green dye-sensitized solar cell based on ZnO nanoparticles as a photoanode and graphene quantum dots as a photo-sensitizer.

PubMed

Zamiri, Golnoush; Bagheri, Samira

2018-02-01

Zero-dimensional graphene quantum dots (GQDs) consist of single- or few-layer graphene with a size less than 20 nm and stand for a new type of QDs with unique properties combining the graphene nature and size-resulted quantum effects. GQDs possess unique optical and electronic properties, and in particular possess a band-gap less than 2.0 eV because of quantum confinement and edge effects. In this study, we investigated the performance of DSSCs using different thicknesses of ZnO nanoparticles as a photo-anode and GQDs as a green photosensitizer. The current voltage (I-V) test results indicate that the performance of DSSCs is improved by increasing the thickness of the photo-anode and the thickness of 40 μm shows the highest efficiency for DSSC device based on ZnO nanoparticles photo-anodes. The DSSC using ZnO nanoparticles as a photo-anode with thickness of 40 μm shows almost same efficiency when we replaced N-719 with GQDs which is confirmed that using GQDs as an alternative to ruthenium based dyes is a new approach for DSSCs. Copyright © 2017 Elsevier Inc. All rights reserved.

Bioinspired engineering of exploration systems for NASA and DoD

NASA Technical Reports Server (NTRS)

Thakoor, Sarita; Chahl, Javaan; Srinivasan, M. V.; Young, L.; Werblin, Frank; Hine, Butler; Zornetzer, Steven

2002-01-01

A new approach called bioinspired engineering of exploration systems (BEES) and its value for solving pressing NASA and DoD needs are described. Insects (for example honeybees and dragonflies) cope remarkably well with their world, despite possessing a brain containing less than 0.01% as many neurons as the human brain. Although most insects have immobile eyes with fixed focus optics and lack stereo vision, they use a number of ingenious, computationally simple strategies for perceiving their world in three dimensions and navigating successfully within it. We are distilling selected insect-inspired strategies to obtain novel solutions for navigation, hazard avoidance, altitude hold, stable flight, terrain following, and gentle deployment of payload. Such functionality provides potential solutions for future autonomous robotic space and planetary explorers. A BEES approach to developing lightweight low-power autonomous flight systems should be useful for flight control of such biomorphic flyers for both NASA and DoD needs. Recent biological studies of mammalian retinas confirm that representations of multiple features of the visual world are systematically parsed and processed in parallel. Features are mapped to a stack of cellular strata within the retina. Each of these representations can be efficiently modeled in semiconductor cellular nonlinear network (CNN) chips. We describe recent breakthroughs in exploring the feasibility of the unique blending of insect strategies of navigation with mammalian visual search, pattern recognition, and image understanding into hybrid biomorphic flyers for future planetary and terrestrial applications. We describe a few future mission scenarios for Mars exploration, uniquely enabled by these newly developed biomorphic flyers.

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

Ballering, Nicholas P.; Rieke, George H.; Gáspár, András, E-mail: ballerin@email.arizona.edu

Observations of debris disks allow for the study of planetary systems, even where planets have not been detected. However, debris disks are often only characterized by unresolved infrared excesses that resemble featureless blackbodies, and the location of the emitting dust is uncertain due to a degeneracy with the dust grain properties. Here, we characterize the Spitzer Infrared Spectrograph spectra of 22 debris disks exhibiting 10 μm silicate emission features. Such features arise from small warm dust grains, and their presence can significantly constrain the orbital location of the emitting debris. We find that these features can be explained by themore » presence of an additional dust component in the terrestrial zones of the planetary systems, i.e., an exozodiacal belt. Aside from possessing exozodiacal dust, these debris disks are not particularly unique; their minimum grain sizes are consistent with the blowout sizes of their systems, and their brightnesses are comparable to those of featureless warm debris disks. These disks are in systems of a range of ages, though the older systems with features are found only around A-type stars. The features in young systems may be signatures of terrestrial planet formation. Analyzing the spectra of unresolved debris disks with emission features may be one of the simplest and most accessible ways to study the terrestrial regions of planetary systems.« less

Hybrid Vibrio cholerae El Tor lacking SXT identified as the cause of a cholera outbreak in the Philippines.

PubMed

Klinzing, David C; Choi, Seon Young; Hasan, Nur A; Matias, Ronald R; Tayag, Enrique; Geronimo, Josefina; Skowronski, Evan; Rashed, Shah M; Kawashima, Kent; Rosenzweig, C Nicole; Gibbons, Henry S; Torres, Brian C; Liles, Veni; Alfon, Alicia C; Juan, Maria Luisa; Natividad, Filipinas F; Cebula, Thomas A; Colwell, Rita R

2015-04-21

Cholera continues to be a global threat, with high rates of morbidity and mortality. In 2011, a cholera outbreak occurred in Palawan, Philippines, affecting more than 500 people, and 20 individuals died. Vibrio cholerae O1 was confirmed as the etiological agent. Source attribution is critical in cholera outbreaks for proper management of the disease, as well as to control spread. In this study, three V. cholerae O1 isolates from a Philippines cholera outbreak were sequenced and their genomes analyzed to determine phylogenetic relatedness to V. cholerae O1 isolates from recent outbreaks of cholera elsewhere. The Philippines V. cholerae O1 isolates were determined to be V. cholerae O1 hybrid El Tor belonging to the seventh-pandemic clade. They clustered tightly, forming a monophyletic clade closely related to V. cholerae O1 hybrid El Tor from Asia and Africa. The isolates possess a unique multilocus variable-number tandem repeat analysis (MLVA) genotype (12-7-9-18-25 and 12-7-10-14-21) and lack SXT. In addition, they possess a novel 15-kb genomic island (GI-119) containing a predicted type I restriction-modification system. The CTXΦ-RS1 array of the Philippines isolates was similar to that of V. cholerae O1 MG116926, a hybrid El Tor strain isolated in Bangladesh in 1991. Overall, the data indicate that the Philippines V. cholerae O1 isolates are unique, differing from recent V. cholerae O1 isolates from Asia, Africa, and Haiti. Furthermore, the results of this study support the hypothesis that the Philippines isolates of V. cholerae O1 are indigenous and exist locally in the aquatic ecosystem of the Philippines. Genetic characterization and phylogenomics analysis of outbreak strains have proven to be critical for probing clonal relatedness to strains isolated in different geographical regions and over time. Recently, extensive genetic analyses of V. cholerae O1 strains isolated in different countries have been done. However, genome sequences of V. cholerae O1 isolates from the Philippines have not been available for epidemiological investigation. In this study, molecular typing and phylogenetic analysis of Vibrio cholerae isolated from both clinical and environmental samples in 2011 confirmed unique genetic features of the Philippines isolates, which are helpful to understand the global epidemiology of cholera. Copyright © 2015 Klinzing et al.

Characterization of Cyanobacterial Hydrocarbon Composition and Distribution of Biosynthetic Pathways

PubMed Central

Coates, R. Cameron; Podell, Sheila; Korobeynikov, Anton; Lapidus, Alla; Pevzner, Pavel; Sherman, David H.; Allen, Eric E.; Gerwick, Lena; Gerwick, William H.

2014-01-01

Cyanobacteria possess the unique capacity to naturally produce hydrocarbons from fatty acids. Hydrocarbon compositions of thirty-two strains of cyanobacteria were characterized to reveal novel structural features and insights into hydrocarbon biosynthesis in cyanobacteria. This investigation revealed new double bond (2- and 3-heptadecene) and methyl group positions (3-, 4- and 5-methylheptadecane) for a variety of strains. Additionally, results from this study and literature reports indicate that hydrocarbon production is a universal phenomenon in cyanobacteria. All cyanobacteria possess the capacity to produce hydrocarbons from fatty acids yet not all accomplish this through the same metabolic pathway. One pathway comprises a two-step conversion of fatty acids first to fatty aldehydes and then alkanes that involves a fatty acyl ACP reductase (FAAR) and aldehyde deformylating oxygenase (ADO). The second involves a polyketide synthase (PKS) pathway that first elongates the acyl chain followed by decarboxylation to produce a terminal alkene (olefin synthase, OLS). Sixty-one strains possessing the FAAR/ADO pathway and twelve strains possessing the OLS pathway were newly identified through bioinformatic analyses. Strains possessing the OLS pathway formed a cohesive phylogenetic clade with the exception of three Moorea strains and Leptolyngbya sp. PCC 6406 which may have acquired the OLS pathway via horizontal gene transfer. Hydrocarbon pathways were identified in one-hundred-forty-two strains of cyanobacteria over a broad phylogenetic range and there were no instances where both the FAAR/ADO and the OLS pathways were found together in the same genome, suggesting an unknown selective pressure maintains one or the other pathway, but not both. PMID:24475038

The Role of CRISPR-Cas Systems in Virulence of Pathogenic Bacteria

PubMed Central

Staals, Raymond H. J.; Endtz, Hubert P.; van Baarlen, Peter; van der Oost, John

2014-01-01

SUMMARY Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes are present in many bacterial and archaeal genomes. Since the discovery of the typical CRISPR loci in the 1980s, well before their physiological role was revealed, their variable sequences have been used as a complementary typing tool in diagnostic, epidemiologic, and evolutionary analyses of prokaryotic strains. The discovery that CRISPR spacers are often identical to sequence fragments of mobile genetic elements was a major breakthrough that eventually led to the elucidation of CRISPR-Cas as an adaptive immunity system. Key elements of this unique prokaryotic defense system are small CRISPR RNAs that guide nucleases to complementary target nucleic acids of invading viruses and plasmids, generally followed by the degradation of the invader. In addition, several recent studies have pointed at direct links of CRISPR-Cas to regulation of a range of stress-related phenomena. An interesting example concerns a pathogenic bacterium that possesses a CRISPR-associated ribonucleoprotein complex that may play a dual role in defense and/or virulence. In this review, we describe recently reported cases of potential involvement of CRISPR-Cas systems in bacterial stress responses in general and bacterial virulence in particular. PMID:24600041

The role of CRISPR-Cas systems in virulence of pathogenic bacteria.

PubMed

Louwen, Rogier; Staals, Raymond H J; Endtz, Hubert P; van Baarlen, Peter; van der Oost, John

2014-03-01

Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes are present in many bacterial and archaeal genomes. Since the discovery of the typical CRISPR loci in the 1980s, well before their physiological role was revealed, their variable sequences have been used as a complementary typing tool in diagnostic, epidemiologic, and evolutionary analyses of prokaryotic strains. The discovery that CRISPR spacers are often identical to sequence fragments of mobile genetic elements was a major breakthrough that eventually led to the elucidation of CRISPR-Cas as an adaptive immunity system. Key elements of this unique prokaryotic defense system are small CRISPR RNAs that guide nucleases to complementary target nucleic acids of invading viruses and plasmids, generally followed by the degradation of the invader. In addition, several recent studies have pointed at direct links of CRISPR-Cas to regulation of a range of stress-related phenomena. An interesting example concerns a pathogenic bacterium that possesses a CRISPR-associated ribonucleoprotein complex that may play a dual role in defense and/or virulence. In this review, we describe recently reported cases of potential involvement of CRISPR-Cas systems in bacterial stress responses in general and bacterial virulence in particular.

DNA origami applications in cancer therapy.

PubMed

Udomprasert, Anuttara; Kangsamaksin, Thaned

2017-08-01

Due to the complexity and heterogeneity of cancer, the development of cancer diagnosis and therapy is still progressing, and a complete understanding of cancer biology remains elusive. Recently, cancer nanomedicine has gained much interest as a promising diagnostic and therapeutic strategy, as a wide range of nanomaterials possess unique physical properties that can render drug delivery systems safer and more effective. Also, targeted drug delivery and precision medicine have now become a new paradigm in cancer therapy. With nanocarriers, chemotherapeutic drugs could be directly delivered into target cancer cells, resulting in enhanced efficiency with fewer side-effects. DNA, a biomolecule with molecular self-assembly properties, has emerged as a versatile nanomaterial to construct multifunctional platforms; DNA nanostructures can be modified with functional groups to improve their utilities as biosensors or drug carriers. Such applications have become possible with the advent of the scaffolded DNA origami method. This breakthrough technique in structural DNA nanotechnology provides an easier and faster way to construct DNA nanostructures with various shapes. Several experiments proved that DNA origami nanostructures possess abilities to enhance efficacies of chemotherapy, reduce adverse side-effects, and even circumvent drug resistance. Here, we highlight the principles of the DNA origami technique and its applications in cancer therapeutics and discuss current challenges and opportunities to improve cancer detection and targeted drug delivery. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Stiff, Thermally Stable and Highly Anisotropic Wood-Derived Carbon Composite Monoliths for Electromagnetic Interference Shielding.

PubMed

Yuan, Ye; Sun, Xianxian; Yang, Minglong; Xu, Fan; Lin, Zaishan; Zhao, Xu; Ding, Yujie; Li, Jianjun; Yin, Weilong; Peng, Qingyu; He, Xiaodong; Li, Yibin

2017-06-28

Electromagnetic interference (EMI) shielding materials for electronic devices in aviation and aerospace not only need lightweight and high shielding effectiveness, but also should withstand harsh environments. Traditional EMI shielding materials often show heavy weight, poor thermal stability, short lifetime, poor tolerance to chemicals, and are hard-to-manufacture. Searching for high-efficiency EMI shielding materials overcoming the above weaknesses is still a great challenge. Herein, inspired by the unique structure of natural wood, lightweight and highly anisotropic wood-derived carbon composite EMI shielding materials have been prepared which possess not only high EMI shielding performance and mechanical stable characteristics, but also possess thermally stable properties, outperforming those metals, conductive polymers, and their composites. The newly developed low-cost materials are promising for specific applications in aerospace electronic devices, especially regarding extreme temperatures.

Formal Integrals and Noether Operators of Nonlinear Hyperbolic Partial Differential Systems Admitting a Rich Set of Symmetries

NASA Astrophysics Data System (ADS)

Startsev, Sergey Ya.

2017-05-01

The paper is devoted to hyperbolic (generally speaking, non-Lagrangian and nonlinear) partial differential systems possessing a full set of differential operators that map any function of one independent variable into a symmetry of the corresponding system. We demonstrate that a system has the above property if and only if this system admits a full set of formal integrals (i.e., differential operators which map symmetries into integrals of the system). As a consequence, such systems possess both direct and inverse Noether operators (in the terminology of a work by B. Fuchssteiner and A.S. Fokas who have used these terms for operators that map cosymmetries into symmetries and perform transformations in the opposite direction). Systems admitting Noether operators are not exhausted by Euler-Lagrange systems and the systems with formal integrals. In particular, a hyperbolic system admits an inverse Noether operator if a differential substitution maps this system into a system possessing an inverse Noether operator.

Multimodal biometric system using rank-level fusion approach.

PubMed

Monwar, Md Maruf; Gavrilova, Marina L

2009-08-01

In many real-world applications, unimodal biometric systems often face significant limitations due to sensitivity to noise, intraclass variability, data quality, nonuniversality, and other factors. Attempting to improve the performance of individual matchers in such situations may not prove to be highly effective. Multibiometric systems seek to alleviate some of these problems by providing multiple pieces of evidence of the same identity. These systems help achieve an increase in performance that may not be possible using a single-biometric indicator. This paper presents an effective fusion scheme that combines information presented by multiple domain experts based on the rank-level fusion integration method. The developed multimodal biometric system possesses a number of unique qualities, starting from utilizing principal component analysis and Fisher's linear discriminant methods for individual matchers (face, ear, and signature) identity authentication and utilizing the novel rank-level fusion method in order to consolidate the results obtained from different biometric matchers. The ranks of individual matchers are combined using the highest rank, Borda count, and logistic regression approaches. The results indicate that fusion of individual modalities can improve the overall performance of the biometric system, even in the presence of low quality data. Insights on multibiometric design using rank-level fusion and its performance on a variety of biometric databases are discussed in the concluding section.

The upside-down water collection system of Syntrichia caninervis.

PubMed

Pan, Zhao; Pitt, William G; Zhang, Yuanming; Wu, Nan; Tao, Ye; Truscott, Tadd T

2016-06-06

Desert plants possess highly evolved water conservation and transport systems, from the root structures that maximize absorption of scarce ground water(1-5), to the minimization of leaf surface area(6) to enhance water retention. Recent attention has focused on leaf structures that are adapted to collect water and promote nucleation from humid air(7-9). Syntrichia caninervis Mitt. (Pottiaceae) is one of the most abundant desert mosses in the world and thrives in an extreme environment with multiple but limited water resources (such as dew, fog, snow and rain), yet the mechanisms for water collection and transport have never been completely revealed. S. caninervis has a unique adaptation: it uses a tiny hair (awn) on the end of each leaf to collect water, in addition to that collected by the leaves themselves. Here we show that the unique multiscale structures of the hair are equipped to collect and transport water in four modes: nucleation of water droplets and films on the leaf hair from humid atmospheres; collection of fog droplets on leaf hairs; collection of splash water from raindrops; and transportation of the acquired water to the leaf itself. Fluid nucleation is accomplished in nanostructures, whereas fog droplets are gathered in areas where a high density of small barbs are present and then quickly transported to the leaf at the base of the hair. Our observations reveal nature's optimization of water collection by coupling relevant multiscale physical plant structures with multiscale sources of water.

Origin of life. Primordial genetics: Information transfer in a pre-RNA world based on self-replicating beta-sheet amyloid conformers.

PubMed

Maury, Carl Peter J

2015-10-07

The question of the origin of life on Earth can largely be reduced to the question of what was the first molecular replicator system that was able to replicate and evolve under the presumably very harsh conditions on the early Earth. It is unlikely that a functional RNA could have existed under such conditions and it is generally assumed that some other kind of information system preceded the RNA world. Here, I present an informational molecular system that is stable, self-replicative, environmentally responsive, and evolvable under conditions characterized by high temperatures, ultraviolet and cosmic radiation. This postulated pregenetic system is based on the amyloid fold, a functionally unique polypeptide fold characterized by a cross beta-sheet structure in which the beta strands are arranged perpendicular to the fiber axis. Beside an extraordinary structural robustness, the amyloid fold possesses a unique ability to transmit information by a three-dimensional templating mechanism. In amyloidogenesis short peptide monomers are added one by one to the growing end of the fiber. From the same monomeric subunits several structural variants of amyloid may be formed. Then, in a self-replicative mode, a specific amyloid conformer can act as a template and confer its spatially encoded information to daughter molecular entities in a repetitive way. In this process, the specific conformational information, the spatially changed organization, is transmitted; the coding element is the steric zipper structure, and recognition occurs by amino acid side chain complementarity. The amyloid information system fulfills several basic requirements of a primordial evolvable replicator system: (i) it is stable under the presumed primitive Earth conditions, (ii) the monomeric building blocks of the informational polymer can be formed from available prebiotic compounds, (iii) the system is self-assembling and self-replicative and (iv) it is adaptive to changes in the environment and evolvable. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

The unique authority of state and local health departments to address obesity.

PubMed

Pomeranz, Jennifer L

2011-07-01

The United States has 51 state health departments and thousands of local health agencies. Their size, structure, and authority differ, but they all possess unique abilities to address obesity. Because they are responsible for public health, they can take various steps themselves and can coordinate efforts with other agencies to further health in all policy domains. I describe the value of health agencies' rule-making authority and clarify this process through 2 case studies involving menu-labeling regulations. I detail rule-making procedures and examine the legal and practical limitations on agency activity. Health departments have many options to effect change in the incidence of obesity but need the support of other government entities and officials.

The Unique Authority of State and Local Health Departments to Address Obesity

PubMed Central

2011-01-01

The United States has 51 state health departments and thousands of local health agencies. Their size, structure, and authority differ, but they all possess unique abilities to address obesity. Because they are responsible for public health, they can take various steps themselves and can coordinate efforts with other agencies to further health in all policy domains. I describe the value of health agencies' rule-making authority and clarify this process through 2 case studies involving menu-labeling regulations. I detail rule-making procedures and examine the legal and practical limitations on agency activity. Health departments have many options to effect change in the incidence of obesity but need the support of other government entities and officials. PMID:21566027

Tunable Gas Sensing Gels by Cooperative Assembly

PubMed Central

Hussain, Abid; Semeano, Ana T. S.; Palma, Susana I. C. J.; Pina, Ana S.; Almeida, José; Medrado, Bárbara F.; Pádua, Ana C. C. S.; Carvalho, Ana L.; Dionísio, Madalena; Li, Rosamaria W. C.; Gamboa, Hugo; Ulijn, Rein V.; Gruber, Jonas; Roque, Ana C. A.

2017-01-01

The cooperative assembly of biopolymers and small molecules can yield functional materials with precisely tunable properties. Here, the fabrication, characterization, and use of multicomponent hybrid gels as selective gas sensors are reported. The gels are composed of liquid crystal droplets self-assembled in the presence of ionic liquids, which further coassemble with biopolymers to form stable matrices. Each individual component can be varied and acts cooperatively to tune gels’ structure and function. The unique molecular environment in hybrid gels is explored for supramolecular recognition of volatile compounds. Gels with distinct compositions are used as optical and electrical gas sensors, yielding a combinatorial response conceptually mimicking olfactory biological systems, and tested to distinguish volatile organic compounds and to quantify ethanol in automotive fuel. The gel response is rapid, reversible, and reproducible. These robust, versatile, modular, pliant electro-optical soft materials possess new possibilities in sensing triggered by chemical and physical stimuli. PMID:28747856

Leveraging natural killer cells for cancer immunotherapy.

PubMed

Grossenbacher, Steven K; Aguilar, Ethan G; Murphy, William J

2017-05-01

Natural killer (NK) cells are potent antitumor effector cells of the innate immune system. Based on their ability to eradicate tumors in vitro and in animal models, significant enthusiasm surrounds the prospect of leveraging human NK cells as vehicles for cancer immunotherapy. While interest in manipulating the effector functions of NK cells has existed for over 30 years, there is renewed optimism for this approach today. Although T cells receive much of the clinical and preclinical attention when it comes to cancer immunotherapy, new strategies are utilizing adoptive NK-cell immunotherapy and monoclonal antibodies and engineered molecules which have been developed to specifically activate NK cells against tumors. Despite the numerous challenges associated with the preclinical and clinical development of NK cell-based therapies for cancer, NK cells possess many unique immunological properties and hold the potential to provide an effective means for cancer immunotherapy.

In vitro interactions between splenocytes and dansylamide dye-embedded nanoparticles detected by flow cytometry

PubMed Central

Nyland, Jennifer F.; Bai, Jennifer J. K.; Katz, Howard E.; Silbergeld, Ellen K.

2009-01-01

Engineered nanoparticles (NPs) possess a range of biological activity. In vitro methods for assessing toxicity and efficacy would be enhanced by simultaneous quantitative information on the behavior of NPs in culture systems and signals of cell response. We have developed a method for visualizing NPs within cells using standard flow cytometric techniques and uniquely designed spherical siloxane NPs with an embedded (covalently bound) dansylamide dye. This method allowed NP visualization without obscuring detection of relevant biomarkers of cell subtype, activation state, and other events relevant to assessing bioactivity. We determined that NPs penetrated cells and induced a range of biological signals consistent with activation and costimulation. These results indicate that NPs may affect cell function at concentrations below those inducing cytotoxicity or apoptosis and demonstrate a novel method to image both localization of NPs and cell-level effects. PMID:19523425

Efficient non-linear two-photon effects from the Cesium 6D manifold

NASA Astrophysics Data System (ADS)

Haluska, Nathan D.; Perram, Glen P.; Rice, Christopher A.

2018-02-01

We report several non-linear process that occur when two-photon pumping the cesium 6D states. Cesium vapor possess some of the largest two-photon pump cross sections in nature. Pumping these cross sections leads to strong amplified spontaneous emission that we observe on over 17 lasing lines. These new fields are strong enough to couple with the pump to create additional tunable lines. We use a heat pipe with cesium densities of 1014 to 1016 cm-3 and 0 to 5 Torr of helium buffer gas. The cesium 6D States are interrogated by both high energy pulses and low power CW sources. We observe four-wave mixing, six-wave mixing, potential two-photon lasing, other unknown nonlinear processes, and the persistence of some processes at low thresholds. This system is also uniquely qualified to support two-photon lasing under the proper conditions.

Cooperativity in Monomeric Enzymes with Single Ligand-Binding Sites

PubMed Central

Porter, Carol M.

2011-01-01

Cooperativity is widespread in biology. It empowers a variety of regulatory mechanisms and impacts both the kinetic and thermodynamic properties of macromolecular systems. Traditionally, cooperativity is viewed as requiring the participation of multiple, spatially distinct binding sites that communicate via ligand-induced structural rearrangements; however, cooperativity requires neither multiple ligand binding events nor multimeric assemblies. An underappreciated manifestation of cooperativity has been observed in the non-Michaelis-Menten kinetic response of certain monomeric enzymes that possess only a single ligand-binding site. In this review, we present an overview of kinetic cooperativity in monomeric enzymes. We discuss the primary mechanisms postulated to give rise to monomeric cooperativity and highlight modern experimental methods that could offer new insights into the nature of this phenomenon. We conclude with an updated list of single subunit enzymes that are suspected of displaying cooperativity, and a discussion of the biological significance of this unique kinetic response. PMID:22137502

DNA Protection Protein, a Novel Mechanism of Radiation Tolerance: Lessons from Tardigrades

PubMed Central

Hashimoto, Takuma; Kunieda, Takekazu

2017-01-01

Genomic DNA stores all genetic information and is indispensable for maintenance of normal cellular activity and propagation. Radiation causes severe DNA lesions, including double-strand breaks, and leads to genome instability and even lethality. Regardless of the toxicity of radiation, some organisms exhibit extraordinary tolerance against radiation. These organisms are supposed to possess special mechanisms to mitigate radiation-induced DNA damages. Extensive study using radiotolerant bacteria suggested that effective protection of proteins and enhanced DNA repair system play important roles in tolerability against high-dose radiation. Recent studies using an extremotolerant animal, the tardigrade, provides new evidence that a tardigrade-unique DNA-associating protein, termed Dsup, suppresses the occurrence of DNA breaks by radiation in human-cultured cells. In this review, we provide a brief summary of the current knowledge on extremely radiotolerant animals, and present novel insights from the tardigrade research, which expand our understanding on molecular mechanism of exceptional radio-tolerability. PMID:28617314

Synthetic approach to thin films of metal-free polyphthalocyanine

NASA Astrophysics Data System (ADS)

Sedlovets, D. M.; Shuvalov, M. V.; Khodos, I. I.; Trofimov, O. V.; Korepanov, V. I.

2018-02-01

Polyphthalocyanines (PPCs) are a unique class of two-dimensional polymers. Like graphene, they possess a 2D-conjugated electronic system, but in contrast to graphene, PPCs have finite band gap, pronounced magnetic properties and high catalytic activity. The applications of PPCs however are hindered by the difficulty to obtain a material of high polymerization degree and structural uniformity. Among PPCs, a metal-free one (H2PPC) is of particularly high interest from both fundamental and applied viewpoints, because the two hydrogen atoms could be substituted by a variety of metals. H2PPC therefore can be considered as a ‘universal polyphthalocyanine matrix’. In this work, we develop a technique for a chemical deposition of thin films of H2PPC on a catalyst-doped surface. High polymerization degree and structural uniformity of the films are confirmed by TEM and FTIR. Raman spectroscopy corroborates the presence of 2D conjugated structure.

Physical Justification for Negative Remanent Magnetization in Homogeneous Nanoparticles

PubMed Central

Gu, Shuo; He, Weidong; Zhang, Ming; Zhuang, Taisen; Jin, Yi; ElBidweihy, Hatem; Mao, Yiwu; Dickerson, James H.; Wagner, Michael J.; Torre, Edward Della; Bennett, Lawrence H.

2014-01-01

The phenomenon of negative remanent magnetization (NRM) has been observed experimentally in a number of heterogeneous magnetic systems and has been considered anomalous. The existence of NRM in homogenous magnetic materials is still in debate, mainly due to the lack of compelling support from experimental data and a convincing theoretical explanation for its thermodynamic validation. Here we resolve the long-existing controversy by presenting experimental evidence and physical justification that NRM is real in a prototype homogeneous ferromagnetic nanoparticle, an europium sulfide nanoparticle. We provide novel insights into major and minor hysteresis behavior that illuminate the true nature of the observed inverted hysteresis and validate its thermodynamic permissibility and, for the first time, present counterintuitive magnetic aftereffect behavior that is consistent with the mechanism of magnetization reversal, possessing unique capability to identify NRM. The origin and conditions of NRM are explained quantitatively via a wasp-waist model, in combination of energy calculations. PMID:25183061

Global Dynamics of Proteins: Bridging Between Structure and Function

PubMed Central

Bahar, Ivet; Lezon, Timothy R.; Yang, Lee-Wei; Eyal, Eran

2010-01-01

Biomolecular systems possess unique, structure-encoded dynamic properties that underlie their biological functions. Recent studies indicate that these dynamic properties are determined to a large extent by the topology of native contacts. In recent years, elastic network models used in conjunction with normal mode analyses have proven to be useful for elucidating the collective dynamics intrinsically accessible under native state conditions, including in particular the global modes of motions that are robustly defined by the overall architecture. With increasing availability of structural data for well-studied proteins in different forms (liganded, complexed, or free), there is increasing evidence in support of the correspondence between functional changes in structures observed in experiments and the global motions predicted by these coarse-grained analyses. These observed correlations suggest that computational methods may be advantageously employed for assessing functional changes in structure and allosteric mechanisms intrinsically favored by the native fold. PMID:20192781

Global dynamics of proteins: bridging between structure and function.

PubMed

Bahar, Ivet; Lezon, Timothy R; Yang, Lee-Wei; Eyal, Eran

2010-01-01

Biomolecular systems possess unique, structure-encoded dynamic properties that underlie their biological functions. Recent studies indicate that these dynamic properties are determined to a large extent by the topology of native contacts. In recent years, elastic network models used in conjunction with normal mode analyses have proven to be useful for elucidating the collective dynamics intrinsically accessible under native state conditions, including in particular the global modes of motions that are robustly defined by the overall architecture. With increasing availability of structural data for well-studied proteins in different forms (liganded, complexed, or free), there is increasing evidence in support of the correspondence between functional changes in structures observed in experiments and the global motions predicted by these coarse-grained analyses. These observed correlations suggest that computational methods may be advantageously employed for assessing functional changes in structure and allosteric mechanisms intrinsically favored by the native fold.

Emerging Issues in Virus Taxonomy

PubMed Central

Mahy, Brian W.J.

2004-01-01

Viruses occupy a unique position in biology. Although they possess some of the properties of living systems such as having a genome, they are actually nonliving infectious entities and should not be considered microorganisms. A clear distinction should be drawn between the terms virus, virion, and virus species. Species is the most fundamental taxonomic category used in all biological classification. In 1991, the International Committee on Taxonomy of Viruses (ICTV) decided that the category of virus species should be used in virus classification together with the categories of genus and family. More than 50 ICTV study groups were given the task of demarcating the 1,550 viral species that were recognized in the 7th ICTV report, which was published in 2000. We briefly describe the changes in virus classification that were introduced in that report. We also discuss recent proposals to introduce a nonlatinized binomial nomenclature for virus species. PMID:15078590

Behavioral development in embryonic and early juvenile cuttlefish (Sepia officinalis).

PubMed

O'Brien, Caitlin E; Mezrai, Nawel; Darmaillacq, Anne-Sophie; Dickel, Ludovic

2017-03-01

Though a mollusc, the cuttlefish Sepia officinalis possesses a sophisticated brain, advanced sensory systems, and a large behavioral repertoire. Cuttlefish provide a unique perspective on animal behavior due to their phylogenic distance from more traditional (vertebrate) models. S. officinalis is well-suited to addressing questions of behavioral ontogeny. As embryos, they can perceive and learn from their environment and experience no direct parental care. A marked progression in learning and behavior is observed during late embryonic and early juvenile development. This improvement is concomitant with expansion and maturation of the vertical lobe, the cephalopod analog of the mammalian hippocampus. This review synthesizes existing knowledge regarding embryonic and juvenile development in this species in an effort to better understand cuttlefish behavior and animal behavior in general. It will serve as a guide to future researchers and encourage greater awareness of the utility of this species to behavioral science. © 2016 Wiley Periodicals, Inc.

Synthesis and Biomedical Applications of Poly((meth)acrylic acid) Brushes.

PubMed

Qu, Zhenyuan; Xu, Hong; Gu, Hongchen

2015-07-15

Poly((meth)acrylic acid) (P(M)AA) brushes possess a number of distinctive properties that are particularly attractive for biomedical applications. This minireview summarizes recent advances in the synthesis and biomedical applications of P(M)AA brushes and brushes containing P(M)AA segments. First, we review different surface-initiated polymerization (SIP) methods, with a focus on recent progress in the surface-initiated controlled/living radical polymerization (SI-CLRP) techniques used to generate P(M)AA brushes with a tailored structure. Next, we discuss biomolecule immobilization methods for P(M)AA brushes, including physical adsorption, covalent binding, and affinity interactions. Finally, typical biomedical applications of P(M)AA brushes are reviewed, and their performance is discussed based on their unique properties. We conclude that P(M)AA brushes are promising biomaterials, and more potential biomedical applications are expected to emerge with the further development of synthetic techniques and increased understanding of their interactions with biological systems.

Simultaneous functional photoacoustic and ultrasonic endoscopy of internal organs in vivo.

PubMed

Yang, Joon-Mo; Favazza, Christopher; Chen, Ruimin; Yao, Junjie; Cai, Xin; Maslov, Konstantin; Zhou, Qifa; Shung, K Kirk; Wang, Lihong V

2012-08-01

At present, clinicians routinely apply ultrasound endoscopy in a variety of interventional procedures that provide treatment solutions for diseased organs. Ultrasound endoscopy not only produces high-resolution images, but also is safe for clinical use and broadly applicable. However, for soft tissue imaging, its mechanical wave-based image contrast fundamentally limits its ability to provide physiologically specific functional information. By contrast, photoacoustic endoscopy possesses a unique combination of functional optical contrast and high spatial resolution at clinically relevant depths, ideal for imaging soft tissues. With these attributes, photoacoustic endoscopy can overcome the current limitations of ultrasound endoscopy. Moreover, the benefits of photoacoustic imaging do not come at the expense of existing ultrasound functions; photoacoustic endoscopy systems are inherently compatible with ultrasound imaging, thereby enabling multimodality imaging with complementary contrast. Here we present simultaneous photoacoustic and ultrasonic dual-mode endoscopy and show its ability to image internal organs in vivo, thus illustrating its potential clinical application.

Simultaneous functional photoacoustic and ultrasonic endoscopy of internal organs in vivo

PubMed Central

Yang, Joon-Mo; Favazza, Christopher; Chen, Ruimin; Yao, Junjie; Cai, Xin; Maslov, Konstantin; Zhou, Qifa; Shung, K. Kirk; Wang, Lihong V.

2013-01-01

Presently, clinicians routinely apply ultrasound endoscopy in a variety of interventional procedures which provide treatment solutions for diseased organs. Ultrasound endoscopy not only produces high resolution images, it is also safe for clinical use and broadly applicable. However, for soft tissue imaging, its mechanical wave-based image contrast fundamentally limits its ability to provide physiologically-specific functional information. By contrast, photoacoustic endoscopy possesses a unique combination of functional optical contrast and high spatial resolution at clinically-relevant depths, ideal for soft tissue imaging. With these attributes, photoacoustic endoscopy can overcome the current limitations of ultrasound endoscopy. Moreover, the benefits of photoacoustic imaging do not come at the expense of existing ultrasound functions; photoacoustic endoscopy systems are inherently compatible with ultrasound imaging, enabling multi-modality imaging with complementary contrast. Here, we present simultaneous photoacoustic and ultrasonic dual-mode endoscopy and demonstrate its ability to image internal organs in vivo, illustrating its potential clinical application. PMID:22797808

Amyloids and prions in plants: Facts and perspectives.

PubMed

Antonets, K S; Nizhnikov, A A

2017-09-03

Amyloids represent protein fibrils that have highly ordered structure with unique physical and chemical properties. Amyloids have long been considered lethal pathogens that cause dozens of incurable diseases in humans and animals. Recent data show that amyloids may not only possess pathogenic properties but are also implicated in the essential biological processes in a variety of prokaryotes and eukaryotes. Functional amyloids have been identified in archaea, bacteria, fungi, and animals, including humans. Plants are one of the most poorly studied groups of organisms in the field of amyloid biology. Although amyloid properties have not been shown under native conditions for any plant protein, studies demonstrating amyloid properties for a set of plant proteins in vitro or in heterologous systems in vivo have been published in recent years. In this review, we systematize the data on the amyloidogenic proteins of plants and their functions and discuss the perspectives of identifying novel amyloids using bioinformatic and proteomic approaches.

The synthesis of monomers with pendent ethynyl groups for modified high performance thermoplastics

NASA Technical Reports Server (NTRS)

Nwokogu, Godson C.; Antoine, Miquel D.; Ansong, Omari

1994-01-01

Synthetic schemes were developed and optimized for twelve new monomers possessing unique structural features and one aspartimide. Two synthetic pathways were compared for preparation of the triarylethane monomers with pendent ethynyl groups. The results show that one of these pathways can be generally applied. The alternative pathway was applicable to the preparation of only one of the twelve compounds, the problem being secondary reactions of the initially formed desired product.

Role of Integrin-Beta 1 in Polycystic Kidney Disease

DTIC Science & Technology

2011-04-01

characterized a novel cell line from human loop of Henle epithelium that can serve as a unique model to study medullary cystic kidney disease-2 (MCKD2) and...Therefore, we further characterized the TIRE131 clone to confirm their loop of Henle origin. Similarly to the loop of Henle epithelium , the...TIRE131 cells: 1) possessed a significant resistance to hyperosmotic growth conditions; 2) formed a functional epithelium with tight junction and

Incredibly Versatile Microbial Fuel Cells Innovative Ideas at HES-SO Valais-Wallis for Solving Topical Problems.

PubMed

Heinzelmann, Elsbeth

2016-01-01

At HES-SO Valais-Wallis, Prof. Fabian Fischer is specialized in microbial fuel cells for novel applications that meet the challenge of producing renewable energies. He and his team possess a unique expertise in bioelectric energy vector generation, phosphate extraction (CHIMIA 2015, 69, 296) and the testing of antimicrobial surfaces. Let's take a look behind the scenes of the Institute of Life Technologies in Sion.

Potent selective nonpeptidic inhibitors of human lung tryptase

PubMed Central

Burgess, Laurence E.; Newhouse, Bradley J.; Ibrahim, Prabha; Rizzi, James; Kashem, Mohammed A.; Hartman, Ann; Brandhuber, Barbara J.; Wright, Clifford D.; Thomson, David S.; Vigers, Guy P. A.; Koch, Kevin

1999-01-01

Human lung tryptase, a homotetrameric serine protease unique to mast cell secretory granules, has been implicated in the pathogenesis of asthma. A hypothesis that tethered symmetrical inhibitors might bridge two adjacent active sites was explored via a rationally designed series of bisbenzamidines. These compounds demonstrated a remarkable distanced-defined structure–activity relationship against human tryptase with one series possessing subnanomolar potencies. Additional evidence supporting the concept of active-site bridging is also presented. PMID:10411878

Conformally flat black hole initial data with one cylindrical end

NASA Astrophysics Data System (ADS)

Gabach Clément, María E.

2010-06-01

We give a complete analytical proof of the existence and uniqueness of extreme-like black hole initial data for Einstein equations, which possess a cylindrical end, analogous to extreme Kerr, extreme Reissner-Nördstrom and extreme Bowen-York's initial data. This extends and refines a previous result (Dain and Clement 2009 Class. Quantum Grav. 26 035020) to a general case of conformally flat, maximal initial data with angular momentum, linear momentum and matter.

Comparative genomics of Fructobacillus spp. and Leuconostoc spp. reveals niche-specific evolution of Fructobacillus spp.

DOE PAGES

Endo, Akihito; Tanizawa, Yasuhiro; Tanaka, Naoto; ...

2015-12-29

In this study, Fructobacillus spp. in fructose-rich niches belong to the family Leuconostocaceae. They were originally classified as Leuconostoc spp., but were later grouped into a novel genus, Fructobacillus , based on their phylogenetic position, morphology and specific biochemical characteristics. The unique characters, so called fructophilic characteristics, had not been reported in the group of lactic acid bacteria, suggesting unique evolution at the genome level. Here we studied four draft genome sequences of Fructobacillus spp. and compared their metabolic properties against those of Leuconostoc spp. As a result, Fructobacillus species possess significantly less protein coding sequences in their small genomes.more » The number of genes was significantly smaller in carbohydrate transport and metabolism. Several other metabolic pathways, including TCA cycle, ubiquinone and other terpenoid-quinone biosynthesis and phosphotransferase systems, were characterized as discriminative pathways between the two genera. The adhE gene for bifunctional acetaldehyde/alcohol dehydrogenase, and genes for subunits of the pyruvate dehydrogenase complex were absent in Fructobacillus spp. The two genera also show different levels of GC contents, which are mainly due to the different GC contents at the third codon position. In conclusion, the present genome characteristics in Fructobacillus spp. suggest reductive evolution that took place to adapt to specific niches.« less

Comparative genomics of Fructobacillus spp. and Leuconostoc spp. reveals niche-specific evolution of Fructobacillus spp.

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

Endo, Akihito; Tanizawa, Yasuhiro; Tanaka, Naoto

In this study, Fructobacillus spp. in fructose-rich niches belong to the family Leuconostocaceae. They were originally classified as Leuconostoc spp., but were later grouped into a novel genus, Fructobacillus , based on their phylogenetic position, morphology and specific biochemical characteristics. The unique characters, so called fructophilic characteristics, had not been reported in the group of lactic acid bacteria, suggesting unique evolution at the genome level. Here we studied four draft genome sequences of Fructobacillus spp. and compared their metabolic properties against those of Leuconostoc spp. As a result, Fructobacillus species possess significantly less protein coding sequences in their small genomes.more » The number of genes was significantly smaller in carbohydrate transport and metabolism. Several other metabolic pathways, including TCA cycle, ubiquinone and other terpenoid-quinone biosynthesis and phosphotransferase systems, were characterized as discriminative pathways between the two genera. The adhE gene for bifunctional acetaldehyde/alcohol dehydrogenase, and genes for subunits of the pyruvate dehydrogenase complex were absent in Fructobacillus spp. The two genera also show different levels of GC contents, which are mainly due to the different GC contents at the third codon position. In conclusion, the present genome characteristics in Fructobacillus spp. suggest reductive evolution that took place to adapt to specific niches.« less

Controlled Thermoresponsive Hydrogels by Stereocomplexed PLA-PEG-PLA Prepared via Hybrid Micelles of Pre-Mixed Copolymers with Different PEG Lengths

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

Abebe, Daniel G.; Fujiwara, Tomoko

2012-09-05

The stereocomplexed hydrogels derived from the micelle mixture of two enantiomeric triblock copolymers, PLLA-PEG-PLLA and PDLA-PEG-PDLA, reported in 2001 exhibited sol-to-gel transition at approximately body temperature upon heating. However, the showed poor storage modulus (ca. 1000 Pa) determined their insufficiency as injectable implant biomaterials for many applications. In this study, the mechanical property of these hydrogels was significantly improved by the modifications of molecular weights and micelle structure. Co-micelles composed of block copolymers with two sizes of PEG block length were shown to possess unique and dissimilar properties from the micelles composed of single-sized block copolymers. The stereomixture of PLA-PEG-PLAmore » comicelles showed a controllable sol-to-gel transition at a wide temperature range of 4 and 80 C. The sol-gel phase diagram displays a linear relationship of temperature versus copolymer composition; hence, a transition at body temperature can be readily achieved by adjusting the mixed copolymer ratio. The resulting thermoresponsive hydrogels exhibit a storage modulus notably higher (ca. 6000 Pa) than that of previously reported hydrogels. As a physical network solely governed by self-reorganization of micelles, followed by stereocomplexation, this unique system offers practical, safe, and simple implantable biomaterials.« less

Demyelinating diseases in Asia.

PubMed

Ochi, Hirofumi; Fujihara, Kazuo

2016-06-01

The present review aims to discuss the recent advances in inflammatory demyelinating diseases of the central nervous system in Asia. Prevalence of multiple sclerosis (MS) in Asia is lower than that in Western countries, although it has been increasing recently. Meanwhile, there seems to be no major difference in neuromyelitis optica (NMO) prevalence in various regions or ethnicities. Thus, the ratios of NMO/NMO spectrum disorder (NMOSD) to MS are higher in Asia as compared with Western countries, indicating that the differential diagnosis between NMO/NMOSD and MS is a major challenge in Asia. Although the detection of aquaporin-4 (AQP4)-antibody is critical in distinguishing NMO/NMOSD from MS, some patients with NMO/NMOSD phenotype are seronegative for AQP4-antibody, and a fraction of those patients possess autoantibody against myelin oligodendrocyte glycoprotein. The clinical profile of Asian MS seems to be essentially similar to that in Western MS after careful exclusion of NMO/NMOSD, although some unique genetic and/or environmental factors may modify the disease in Asians. MS prevalence has been low but is increasing in Asia. In contrast, NMO/NMOSD prevalence seems relatively constant in the world. Asian MS is not fundamentally different from Western MS, but some genetic and/or environmental differences may cause some features unique to Asian patients.

Ag-NPs embedded in two novel Zn3/Zn5-cluster-based metal-organic frameworks for catalytic reduction of 2/3/4-nitrophenol.

PubMed

Wu, Xue-Qian; Huang, Dan-Dan; Zhou, Zhi-Hang; Dong, Wen-Wen; Wu, Ya-Pan; Zhao, Jun; Li, Dong-Sheng; Zhang, Qichun; Bu, Xianhui

2017-02-21

By utilizing symmetrical pentacarboxylate ligands, 3,5-di(2',5'-dicarboxylphenyl)benzoic acid (H 5 L1) and 3,5-di(2',4'-dicarboxylphenyl)benzoic acid (H 5 L2), two novel porous Zn-MOFs, [Zn 5 (μ 3 -H 2 O) 2 (L1) 2 ]·3DMA·4H 2 O (CTGU-3) and [Zn 3 (μ 3 -OH)L2(H 2 O) 3 ]·H 2 O (CTGU-4) have been synthesized under solvothermal conditions. CTGU-3 and CTGU-4 exhibit 3D microporous frameworks with flu and dia topologies and possess unique secondary building units [Zn 5 (μ 3 -H 2 O) 2 (RCO 2 ) 6 ] and [Zn 3 (μ 3 -OH)(RCO 2 ) 3 ], respectively. Such porous systems create a unique space or surface to accommodate Ag nanoparticles (Ag NPs), which could efficiently prevent Ag NPs from aggregation and leaching. In this work, two new Ag@Zn-MOF composites, denoted as Ag@CTGU, have been successfully fabricated through solution infiltration, for the reduction of nitrophenol. Compared with CTGU-4, CTGU-3 shows enhanced catalytic efficiency toward the reaction when it is used as a catalyst support of Ag NPs. Moreover, gas sorption and luminescence properties of two compounds were also investigated.

Aggregates, Crystals, Gels, and Amyloids: Intracellular and Extracellular Phenotypes at the Crossroads of Immunoglobulin Physicochemical Property and Cell Physiology

PubMed Central

2013-01-01

Recombinant immunoglobulins comprise an important class of human therapeutics. Although specific immunoglobulins can be purposefully raised against desired antigen targets by various methods, identifying an immunoglobulin clone that simultaneously possesses potent therapeutic activities and desirable manufacturing-related attributes often turns out to be challenging. The variable domains of individual immunoglobulins primarily define the unique antigen specificities and binding affinities inherent to each clone. The primary sequence of the variable domains also specifies the unique physicochemical properties that modulate various aspects of individual immunoglobulin life cycle, starting from the biosynthetic steps in the endoplasmic reticulum, secretory pathway trafficking, secretion, and the fate in the extracellular space and in the endosome-lysosome system. Because of the diverse repertoire of immunoglobulin physicochemical properties, some immunoglobulin clones' intrinsic properties may manifest as intriguing cellular phenotypes, unusual solution behaviors, and serious pathologic outcomes that are of scientific and clinical importance. To gain renewed insights into identifying manufacturable therapeutic antibodies, this paper catalogs important intracellular and extracellular phenotypes induced by various subsets of immunoglobulin clones occupying different niches of diverse physicochemical repertoire space. Both intrinsic and extrinsic factors that make certain immunoglobulin clones desirable or undesirable for large-scale manufacturing and therapeutic use are summarized. PMID:23533417

Use and application of gelatin as potential biodegradable packaging materials for food products.

PubMed

Nur Hanani, Z A; Roos, Y H; Kerry, J P

2014-11-01

The manufacture and potential application of biodegradable films for food application has gained increased interest as alternatives to conventional food packaging polymers due to the sustainable nature associated with their availability, broad and abundant source range, compostability, environmentally-friendly image, compatibility with foodstuffs and food application, etc. Gelatin is one such material and is a unique and popularly used hydrocolloid by the food industry today due to its inherent characteristics, thereby potentially offering a wide range of further and unique industrial applications. Gelatin from different sources have different physical and chemical properties as they contain different amino acid contents which are responsible for the varying characteristics observed upon utilization in food systems and when being utilized more specifically, in the manufacture of films. Packaging films can be successfully produced from all gelatin sources and the behaviour and characteristics of gelatin-based films can be altered through the incorporation of other food ingredients to produce composite films possessing enhanced physical and mechanical properties. This review will present the current situation with respect to gelatin usage as a packaging source material and the challenges that remain in order to move the manufacture of gelatin-based films nearer to commercial reality. Copyright © 2014 Elsevier B.V. All rights reserved.

Computer-based classification of bacteria species by analysis of their colonies Fresnel diffraction patterns

NASA Astrophysics Data System (ADS)

Suchwalko, Agnieszka; Buzalewicz, Igor; Podbielska, Halina

2012-01-01

In the presented paper the optical system with converging spherical wave illumination for classification of bacteria species, is proposed. It allows for compression of the observation space, observation of Fresnel patterns, diffraction pattern scaling and low level of optical aberrations, which are not possessed by other optical configurations. Obtained experimental results have shown that colonies of specific bacteria species generate unique diffraction signatures. Analysis of Fresnel diffraction patterns of bacteria colonies can be fast and reliable method for classification and recognition of bacteria species. To determine the unique features of bacteria colonies diffraction patterns the image processing analysis was proposed. Classification can be performed by analyzing the spatial structure of diffraction patterns, which can be characterized by set of concentric rings. The characteristics of such rings depends on the bacteria species. In the paper, the influence of basic features and ring partitioning number on the bacteria classification, is analyzed. It is demonstrated that Fresnel patterns can be used for classification of following species: Salmonella enteritidis, Staplyococcus aureus, Proteus mirabilis and Citrobacter freundii. Image processing is performed by free ImageJ software, for which a special macro with human interaction, was written. LDA classification, CV method, ANOVA and PCA visualizations preceded by image data extraction were conducted using the free software R.

Bionic Nanosystems

NASA Astrophysics Data System (ADS)

Sebastian Mannoor, Manu

Direct multidimensional integration of functional electronics and mechanical elements with viable biological systems could allow for the creation of bionic systems and devices possessing unique and advanced capabilities. For example, the ability to three dimensionally integrate functional electronic and mechanical components with biological cells and tissue could enable the creation of bionic systems that can have tremendous impact in regenerative medicine, prosthetics, and human-machine interfaces. However, as a consequence of the inherent dichotomy in material properties and limitations of conventional fabrication methods, the attainment of truly seamless integration of electronic and/or mechanical components with biological systems has been challenging. Nanomaterials engineering offers a general route for overcoming these dichotomies, primarily due to the existence of a dimensional compatibility between fundamental biological functional units and abiotic nanomaterial building blocks. One area of compelling interest for bionic systems is in the field of biomedical sensing, where the direct interfacing of nanosensors onto biological tissue or the human body could stimulate exciting opportunities such as on-body health quality monitoring and adaptive threat detection. Further, interfacing of antimicrobial peptide based bioselective probes onto the bionic nanosensors could offer abilities to detect pathogenic bacteria with bio-inspired selectivity. Most compellingly, when paired with additive manufacturing techniques such as 3D printing, these characteristics enable three dimensional integration and merging of a variety of functional materials including electronic, structural and biomaterials with viable biological cells, in the precise anatomic geometries of human organs, to form three dimensionally integrated, multi-functional bionic hybrids and cyborg devices with unique capabilities. In this thesis, we illustrate these approaches using three representative bionic systems: 1) Bionic Nanosensors: featuring bio-integrated graphene nanosensors for ubiquitous sensing, 2) Bionic Organs: featuring 3D printed bionic ears with three dimensionally integrated electronics and 3) Bionic Leaves: describing ongoing work in the direction of the creation of a bionic leaf enabled by the integration of plant derived photosynthetic functional units with electronic materials and components into a leaf-shaped hierarchical structure for harvesting photosynthetic bioelectricity.

Utilization of geoinformation tools for the development of forest fire hazard mapping system: example of Pekan fire, Malaysia

NASA Astrophysics Data System (ADS)

Mahmud, Ahmad Rodzi; Setiawan, Iwan; Mansor, Shattri; Shariff, Abdul Rashid Mohamed; Pradhan, Biswajeet; Nuruddin, Ahmed

2009-12-01

A study in modeling fire hazard assessment will be essential in establishing an effective forest fire management system especially in controlling and preventing peat fire. In this paper, we have used geographic information system (GIS), in combination with other geoinformation technologies such as remote sensing and computer modeling, for all aspects of wild land fire management. Identifying areas that have a high probability of burning is an important component of fire management planning. The development of spatially explicit GIS models has greatly facilitated this process by allowing managers to map and analyze variables contributing to fire occurrence across large, unique geographic units. Using the model and its associated software engine, the fire hazard map was produced. Extensive avenue programming scripts were written to provide additional capabilities in the development of these interfaces to meet the full complement of operational software considering various users requirements. The system developed not only possesses user friendly step by step operations to deliver the fire vulnerability mapping but also allows authorized users to edit, add or modify parameters whenever necessary. Results from the model can support fire hazard mapping in the forest and enhance alert system function by simulating and visualizing forest fire and helps for contingency planning.

Biaxially stretchable supercapacitors based on the buckled hybrid fiber electrode array

NASA Astrophysics Data System (ADS)

Zhang, Nan; Zhou, Weiya; Zhang, Qiang; Luan, Pingshan; Cai, Le; Yang, Feng; Zhang, Xiao; Fan, Qingxia; Zhou, Wenbin; Xiao, Zhuojian; Gu, Xiaogang; Chen, Huiliang; Li, Kewei; Xiao, Shiqi; Wang, Yanchun; Liu, Huaping; Xie, Sishen

2015-07-01

In order to meet the growing need for smart bionic devices and epidermal electronic systems, biaxial stretchability is essential for energy storage units. Based on porous single-walled carbon nanotube/poly(3,4-ethylenedioxythiophene) (SWCNT/PEDOT) hybrid fiber, we designed and fabricated a biaxially stretchable supercapacitor, which possesses a unique configuration of the parallel buckled hybrid fiber array. Owing to the reticulate SWCNT film and the improved fabrication technique, the hybrid fiber retained its porous architecture both outwardly and inwardly, manifesting a superior capacity of 215 F g-1. H3PO4-polyvinyl alcohol gel with an optimized component ratio was introduced as both binder and stretchable electrolyte, which contributed to the regularity and stability of the buckled fiber array. The buckled structure and the quasi one-dimensional character of the fibers endow the supercapacitor with 100% stretchability along all directions. In addition, the supercapacitor exhibited good transparency, as well as excellent electrochemical properties and stability after being stretched 5000 times.In order to meet the growing need for smart bionic devices and epidermal electronic systems, biaxial stretchability is essential for energy storage units. Based on porous single-walled carbon nanotube/poly(3,4-ethylenedioxythiophene) (SWCNT/PEDOT) hybrid fiber, we designed and fabricated a biaxially stretchable supercapacitor, which possesses a unique configuration of the parallel buckled hybrid fiber array. Owing to the reticulate SWCNT film and the improved fabrication technique, the hybrid fiber retained its porous architecture both outwardly and inwardly, manifesting a superior capacity of 215 F g-1. H3PO4-polyvinyl alcohol gel with an optimized component ratio was introduced as both binder and stretchable electrolyte, which contributed to the regularity and stability of the buckled fiber array. The buckled structure and the quasi one-dimensional character of the fibers endow the supercapacitor with 100% stretchability along all directions. In addition, the supercapacitor exhibited good transparency, as well as excellent electrochemical properties and stability after being stretched 5000 times. Electronic supplementary information (ESI) available: SEM images of the twist-first hybrid fiber, TEM images of SWCNT/PEDOT hybrid bundles, Raman spectra and FTIR spectra of the hybrid electrodes, CVs of the pristine, bended and wound supercapacitor, transmittance spectra of the pristine and stretched supercapacitor, demo video of the supercapacitor. See DOI: 10.1039/c5nr03027g

R 5T 4 compounds - unique multifunctional intermetallics for basic research and applications

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

Mudryk, Yaroslav

The unique properties of the rare-earth elements and their alloys have brought them from relative obscurity to high profile use in common high-tech applications. The broad technological impact of these remarkable materials may have never been known by the general public if not for the supply concerns that placed the rare-earth materials on the front page of newspapers and magazines. Neodymium and dysprosium, two essential components of Nd 2Fe 14B-based high-performance permanent magnets, have drawn much attention and have been deemed critical materials for many energy-related applications. Ironically, the notoriety of rare-earth elements and their alloys is the result ofmore » a global movement to reduce their use in industrial applications and, thus, ease concerns about their supply and ultimately to reduce their position in high-tech supply chains. Research into the applications of lanthanide alloys has been de-emphasized recently due to the perception that industry is moving away from the use of rare-earth elements in new products. While lanthanide supply challenges justify efforts to diversify the supply chain, a strategy to completely replace the materials overlooks the reasons rare earths became important in the first place -- their unique properties are too beneficial to ignore. Rare-earth alloys and compounds possess truly exciting potential for basic science exploration and application development such as solid-state caloric cooling. In this brief review, we touch upon several promising systems containing lanthanide elements that show important and interesting magnetism-related phenomena.« less

Young children's preference for unique owned objects.

PubMed

Gelman, Susan A; Davidson, Natalie S

2016-10-01

An important aspect of human thought is the value we place on unique individuals. Adults place higher value on authentic works of art than exact replicas, and young children at times value their original possessions over exact duplicates. What is the scope of this preference in early childhood, and when do children understand its subjective nature? On a series of trials, we asked three-year-olds (N=36) to choose between two toys for either themselves or the researcher: an old (visibly used) toy vs. a new (more attractive) toy matched in type and appearance (e.g., old vs. brand-new blanket). Focal pairs contrasted the child's own toy with a matched new object; Control pairs contrasted toys the child had never seen before. Children preferred the old toys for Focal pairs only, and treated their own preferences as not shared by the researcher. By 3years of age, young children place special value on unique individuals, and understand the subjective nature of that value. Copyright © 2016 Elsevier B.V. All rights reserved.

Autobiographical memory functions of nostalgia in comparison to rumination and counterfactual thinking: similarity and uniqueness.

PubMed

Cheung, Wing-Yee; Wildschut, Tim; Sedikides, Constantine

2018-02-01

We compared and contrasted nostalgia with rumination and counterfactual thinking in terms of their autobiographical memory functions. Specifically, we assessed individual differences in nostalgia, rumination, and counterfactual thinking, which we then linked to self-reported functions or uses of autobiographical memory (Self-Regard, Boredom Reduction, Death Preparation, Intimacy Maintenance, Conversation, Teach/Inform, and Bitterness Revival). We tested which memory functions are shared and which are uniquely linked to nostalgia. The commonality among nostalgia, rumination, and counterfactual thinking resides in their shared positive associations with all memory functions: individuals who evinced a stronger propensity towards past-oriented thought (as manifested in nostalgia, rumination, and counterfactual thinking) reported greater overall recruitment of memories in the service of present functioning. The uniqueness of nostalgia resides in its comparatively strong positive associations with Intimacy Maintenance, Teach/Inform, and Self-Regard and weak association with Bitterness Revival. In all, nostalgia possesses a more positive functional signature than do rumination and counterfactual thinking.

Young Children's Preference for Unique Owned Objects

PubMed Central

Gelman, Susan A.; Davidson, Natalie S.

2016-01-01

An important aspect of human thought is the value we place on unique individuals. Adults place higher value on authentic works of art than exact replicas, and young children at times value their original possessions over exact duplicates. What is the scope of this preference in early childhood, and when do children understand its subjective nature? On a series of trials, we asked three-year-olds (N=36) to choose between two toys for either themselves or the researcher: an old (visibly used) toy versus a new (more attractive) toy matched in type and appearance (e.g., old vs. brand-new blanket). Focal pairs contrasted the child's own toy with a matched new object; Control pairs contrasted toys the child had never seen before. Children preferred the old toys for Focal pairs only, and treated their own preferences as not shared by the researcher. By 3 years of age, young children place special value on unique individuals, and understand the subjective nature of that value. PMID:27395441

Robust and Soft Elastomeric Electronics Tolerant to Our Daily Lives.

PubMed

Sekiguchi, Atsuko; Tanaka, Fumiaki; Saito, Takeshi; Kuwahara, Yuki; Sakurai, Shunsuke; Futaba, Don N; Yamada, Takeo; Hata, Kenji

2015-09-09

Clothes represent a unique textile, as they simultaneously provide robustness against our daily activities and comfort (i.e., softness). For electronic devices to be fully integrated into clothes, the devices themselves must be as robust and soft as the clothes themselves. However, to date, no electronic device has ever possessed these properties, because all contain components fabricated from brittle materials, such as metals. Here, we demonstrate robust and soft elastomeric devices where every component possesses elastomeric characteristics with two types of single-walled carbon nanotubes added to provide the necessary electronic properties. Our elastomeric field effect transistors could tolerate every punishment our clothes experience, such as being stretched (elasticity: ∼ 110%), bent, compressed (>4.0 MPa, by a car and heels), impacted (>6.26 kg m/s, by a hammer), and laundered. Our electronic device provides a novel design principle for electronics and wide range applications even in research fields where devices cannot be used.

Globally optimal superconducting magnets part II: symmetric MSE coil arrangement.

PubMed

Tieng, Quang M; Vegh, Viktor; Brereton, Ian M

2009-01-01

A globally optimal superconducting magnet coil design procedure based on the Minimum Stored Energy (MSE) current density map is outlined. The method has the ability to arrange coils in a manner that generates a strong and homogeneous axial magnetic field over a predefined region, and ensures the stray field external to the assembly and peak magnetic field at the wires are in acceptable ranges. The outlined strategy of allocating coils within a given domain suggests that coils should be placed around the perimeter of the domain with adjacent coils possessing alternating winding directions for optimum performance. The underlying current density maps from which the coils themselves are derived are unique, and optimized to possess minimal stored energy. Therefore, the method produces magnet designs with the lowest possible overall stored energy. Optimal coil layouts are provided for unshielded and shielded short bore symmetric superconducting magnets.

Enhanced cortical connectivity in absolute pitch musicians: a model for local hyperconnectivity.

PubMed

Loui, Psyche; Li, H Charles; Hohmann, Anja; Schlaug, Gottfried

2011-04-01

Connectivity in the human brain has received increased scientific interest in recent years. Although connection disorders can affect perception, production, learning, and memory, few studies have associated brain connectivity with graded variations in human behavior, especially among normal individuals. One group of normal individuals who possess unique characteristics in both behavior and brain structure is absolute pitch (AP) musicians, who can name the appropriate pitch class of any given tone without a reference. Using diffusion tensor imaging and tractography, we observed hyperconnectivity in bilateral superior temporal lobe structures linked to AP possession. Furthermore, volume of tracts connecting left superior temporal gyrus to left middle temporal gyrus predicted AP performance. These findings extend previous reports of exaggerated temporal lobe asymmetry, may explain the higher incidence of AP in special populations, and may provide a model for understanding the heightened connectivity that is thought to underlie savant skills and cases of exceptional creativity.

Antibody repertoire development in camelids.

PubMed

De Genst, Erwin; Saerens, Dirk; Muyldermans, Serge; Conrath, Katja

2006-01-01

The humoral immune response of the Camelidae is unique as these animals are the only known mammals that seem to possess functional homodimeric heavy-chain antibodies besides the classical heteromeric antibodies composed of heavy (H) and light (L) chains. By definition, the heavy-chain antibodies lack the L-chain, and it was noticed that their H-chain is devoid of the typical first constant domain (CH1) and contains a dedicated variable domain, referred to as VHH. The VHH exon is assembled from separate V-D-J gene segments. The recombined VHH region is subjected to somatic hypermutations; however, the timing and actual mechanism of the class switch from mu to the dedicated gamma-isotype remains elusive. Interestingly, antigen-specific VHHs are easily retrieved after panning of a phage-displayed rearranged V-gene pool cloned from an immunised camelid. These single-domain antigen binding entities possess a number of biophysical properties that offer particular advantages in various medical and biotechnological applications.

Enhanced Cortical Connectivity in Absolute Pitch Musicians: A Model for Local Hyperconnectivity

PubMed Central

Loui, Psyche; Charles Li, Hui C.; Hohmann, Anja; Schlaug, Gottfried

2010-01-01

Connectivity in the human brain has received increased scientific interest in recent years. Although connection disorders can affect perception, production, learning, and memory, few studies have associated brain connectivity with graded variations in human behavior, especially among normal individuals. One group of normal individuals who possess unique characteristics in both behavior and brain structure is absolute pitch (AP) musicians, who can name the appropriate pitch class of any given tone without a reference. Using diffusion tensor imaging and tractography, we observed hyperconnectivity in bilateral superior temporal lobe structures linked to AP possession. Furthermore, volume of tracts connecting left superior temporal gyrus to left middle temporal gyrus predicted AP performance. These findings extend previous reports of exaggerated temporal lobe asymmetry, may explain the higher incidence of AP in developmental disorders, and may provide a model for understanding the heightened connectivity that is thought to underlie savant skills and cases of exceptional creativity. PMID:20515408

Purification and partial characterization of bacteriocin produced by Lactococcus lactis ssp. lactis LL171.

PubMed

Kumari, Archana; Akkoç, Nefise; Akçelik, Mustafa

2012-04-01

Lactic acid bacteria (LAB) are possessing ability to synthesize antimicrobial compounds (like bacteriocin) during their growth. In this regard, novel bacteriocin compound secreting capability of LAB isolated from Tulum Cheese in Turkey was demonstrated. The synthesized bacteriocin was purified by ammonium sulphate precipitation, dialysis and gel filtration. The molecular weight (≈3.4 kDa) of obtained bacteriocin was confirmed by SDS-PAGE, which revealed single peptide band. Molecular identification of LAB strain isolated from Tulum Cheese was conducted using 16S rDNA gene sequencing as Lactococcus lactis ssp. lactis LL171. The amino acid sequences (KKIDTRTGKTMEKTEKKIELSLKNMKTAT) of the bacteriocin from Lactococcus lactis ssp. lactis LL171 was found unique and novel than reported bacteriocins. Further, the bacteriocin was possessed the thermostable property and active at wide range of pH values from 1 to 11. Thus, bacteriocin reported in this study has the potential applications property as food preservative agent.

Phosphorus K4 Crystal: A New Stable Allotrope

PubMed Central

Liu, Jie; Zhang, Shunhong; Guo, Yaguang; Wang, Qian

2016-01-01

The intriguing properties of phosphorene motivate scientists to further explore the structures and properties of phosphorus materials. Here, we report a new allotrope named K4 phosphorus composed of three-coordinated phosphorus atoms in non-layered structure which is not only dynamically and mechanically stable, but also possesses thermal stability comparable to that of the orthorhombic black phosphorus (A17). Due to its unique configuration, K4 phosphorus exhibits exceptional properties: it possesses a band gap of 1.54 eV which is much larger than that of black phosphorus (0.30 eV), and it is stiffer than black phosphorus. The band gap of the newly predicted phase can be effectively tuned by appling hydrostastic pressure. In addition, K4 phosphorus exibits a good light absorption in visible and near ultraviolet region. These findings add additional features to the phosphorus family with new potential applications in nanoelectronics and nanomechanics. PMID:27857232

[Ag2M(Te2O5)2]SO4 (M = CeIV or ThIV): A New Purely Inorganic d/f-Heterometallic Cationic Material.

PubMed

Poe, Todd N; White, Frankie D; Proust, Vanessa; Villa, Eric M; Polinski, Matthew J

2018-05-07

Two new isotypic d/f-heterometallic purely inorganic cationic materials, [Ag 2 M(Te 2 O 5 ) 2 ]SO 4 (M = Ce IV or Th IV ), were synthesized using the metal oxides (MO 2 and TeO 2 ), silver nitrate, and sulfuric acid under mild hydrothermal conditions. The prepared materials were characterized via single-crystal X-ray diffraction, which revealed that the materials possess a 3D framework of corner-sharing Te 2 O 5 2- units. The tellurite framework creates four unique pores, three of which are occupied by the M IV and Ag I metal centers. The tellurite network, metal coordination, and total charge yield a cationic framework, which is charge-balanced by electrostatically bound sulfate anions residing in the largest of the four framework pores. These materials also possess Ag I in a ligand-imposed linear geometry.

Biochemical-Pathway Diversity in Archaebacteria

DTIC Science & Technology

1990-08-30

Classification) (U) Biochemical-pathway diversity in Archaebacteria 12 PERSONAL AUTHOR(S) I Jensen, Roy-A. i3o. TYPE OF REN" RT 12b. Tki~ 0’E D-30-9 4...by block numtb.sj FIEL I ROU I SIGRLJP Archaebacteria , biochemical diversity, prephenate 06 03. 1 dehydratase, aromatic amino acid biosynthesis t...1988 RE10SE: lo assess the extent to which the archaebacteria possess unique biochemical features of aromatic amino acid biosynthesis and regulation and

Hazardous-Materials Robot

NASA Technical Reports Server (NTRS)

Stone, Henry W.; Edmonds, Gary O.

1995-01-01

Remotely controlled mobile robot used to locate, characterize, identify, and eventually mitigate incidents involving hazardous-materials spills/releases. Possesses number of innovative features, allowing it to perform mission-critical functions such as opening and unlocking doors and sensing for hazardous materials. Provides safe means for locating and identifying spills and eliminates risks of injury associated with use of manned entry teams. Current version of vehicle, called HAZBOT III, also features unique mechanical and electrical design enabling vehicle to operate safely within combustible atmosphere.

Embryology in the era of proteomics.

PubMed

Katz-Jaffe, Mandy G; McReynolds, Susanna

2013-03-15

Proteomic technologies have begun providing evidence that viable embryos possess unique protein profiles. Some of these potential protein biomarkers have been identified as extracellular and could be used in the development of a noninvasive quantitative method for embryo assessment. The field of assisted reproductive technologies would benefit from defining the human embryonic proteome and secretome, thereby expanding our current knowledge of embryonic cellular processes. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Application of Advanced Laser Diagnostics to High-Impact Technologies: Science and Applications of Ultrafast, Ultraintense Lasers

DTIC Science & Technology

2013-11-01

ultrashort - pulse lasers because of the very large photon density. As the intensity increases, the electric field of the light can modify the Coulomb ...absorption studies of argon clusters in intense laser pulses ,” Physics of Plasmas 16(4), 043301-1 – 043301-5. Lu, W., Nicoul, M., Shymanovich, U... intensity of ultrashort - pulse lasers , possess unique and advantageous capabilities for use in a wide variety of applications and are

Nonexistence of degenerate horizons in static vacua and black hole uniqueness

NASA Astrophysics Data System (ADS)

Khuri, Marcus; Woolgar, Eric

2018-02-01

We show that in any spacetime dimension D ≥ 4, degenerate components of the event horizon do not exist in static vacuum configurations with positive cosmological constant. We also show that without a cosmological constant asymptotically flat solutions cannot possess a degenerate horizon component. Several independent proofs are presented. One proof follows easily from differential geometry in the near-horizon limit, while others use Bakry-Émery-Ricci bounds for static Einstein manifolds.

Cubosomes as targeted drug delivery systems - a biopharmaceutical approach.

PubMed

Lakshmi, Naga M; Yalavarthi, Prasanna R; Vadlamudi, Harini C; Thanniru, Jyotsna; Yaga, Gowri; K, Haritha

2014-01-01

Cubosomes are reversed bicontinuous cubic phases and possess unique physicochemical properties. These special systems are receiving much attention for the delivery of various hydrophilic, hydrophobic and amphiphilic drugs with enhanced bioavailability and high loading capacity. A wide variety of drugs are applicable for cubosome formulation for various routes of delivery. The lipids used in cubosome formulation are more stable and offer stability to the formulation during shelf-life. The article reviews about the back ground, techniques of cubosome preparation such as high pressure homogenization, probe ultrasonication and automated cubosome preparation; and also methods of cubosomes preparation such as top down, bottom up and other methods with pictorial presentation. This article emphasizes the phase transition and also targeted approaches of cubosomes. The characterization studies for cubosomes such as cryo transmission electron microscopy, differential scanning calorimetry and scanning electron microscopy followed by in-vitro and in-vivo evaluation studies of cubosomes were explained with appropriate examples. Recent applications of cubosomes were explained with reference to flurbiprofen, odorranalectin, diazepam and dexamethasone. The advantages, disadvantages and limitations of cubosomal technology were emphasized.

Emerging Roles for Extracellular Vesicles in Tissue Engineering and Regenerative Medicine

PubMed Central

Lamichhane, Tek N.; Sokic, Sonja; Schardt, John S.; Raiker, Rahul S.; Lin, Jennifer W.

2015-01-01

Extracellular vesicles (EVs)—comprising a heterogeneous population of cell-derived lipid vesicles including exosomes, microvesicles, and others—have recently emerged as both mediators of intercellular information transfer in numerous biological systems and vehicles for drug delivery. In both roles, EVs have immense potential to impact tissue engineering and regenerative medicine applications. For example, the therapeutic effects of several progenitor and stem cell-based therapies have been attributed primarily to EVs secreted by these cells, and EVs have been recently reported to play direct roles in injury-induced tissue regeneration processes in multiple physiological systems. In addition, EVs have been utilized for targeted drug delivery in regenerative applications and possess unique potential to be harnessed as patient-derived drug delivery vehicles for personalized medicine. This review discusses EVs in the context of tissue repair and regeneration, including their utilization as drug carriers and their crucial role in cell-based therapies. Furthermore, the article highlights the growing need for bioengineers to understand, consider, and ultimately design and specifically control the activity of EVs to maximize the efficacy of tissue engineering and regenerative therapies. PMID:24957510

Boundedness in a quasilinear fully parabolic Keller-Segel system with logistic source

NASA Astrophysics Data System (ADS)

Zhang, Qingshan; Li, Yuxiang

2015-10-01

This paper deals with the Neumann boundary value problem for the system u_t = nabla \\cdot (D(u) nabla u) - nabla \\cdot (S(u) nabla v) + f(u), &quad x in Ω, t > 0, v_t = Δ v - v + u, &quad x in Ω, t > 0 in a smooth bounded domain {Ωsubset{{R}}^n} {(n≥1)}, where the functions D( u) and S( u) are supposed to be smooth satisfying {D(u)≥ Mu^{-α}} and {S(u)≤ Mu^{β}} with M > 0, {αin{{R}}} and {βin{{R}}} for all {u≥1}, and the logistic source f( u) is smooth fulfilling {f(0)≥0} as well as {f(u)≤ a-μ u^{γ}} with {a≥0}, {μ > 0} and {γ≥1} for all {u≥0}. It is shown that if α + 2β < γ - 1 + 2/n, &quad for 1 ≤ γ < 2, γ - 1 + 4/n + 2, &quad for γ ≥ 2, then for sufficiently smooth initial data, the problem possesses a unique global classical solution which is uniformly bounded.

Atomic switch: atom/ion movement controlled devices for beyond von-neumann computers.

PubMed

Hasegawa, Tsuyoshi; Terabe, Kazuya; Tsuruoka, Tohru; Aono, Masakazu

2012-01-10

An atomic switch is a nanoionic device that controls the diffusion of metal ions/atoms and their reduction/oxidation processes in the switching operation to form/annihilate a conductive path. Since metal atoms can provide a highly conductive channel even if their cluster size is in the nanometer scale, atomic switches may enable downscaling to smaller than the 11 nm technology node, which is a great challenge for semiconductor devices. Atomic switches also possess novel characteristics, such as high on/off ratios, very low power consumption and non-volatility. The unique operating mechanisms of these devices have enabled the development of various types of atomic switch, such as gap-type and gapless-type two-terminal atomic switches and three-terminal atomic switches. Novel functions, such as selective volatile/nonvolatile, synaptic, memristive, and photo-assisted operations have been demonstrated. Such atomic switch characteristics can not only improve the performance of present-day electronic systems, but also enable development of new types of electronic systems, such as beyond von- Neumann computers. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Opioid Receptor Probes Derived from Cycloaddition of the Hallucinogen Natural Product Salvinorin A†

PubMed Central

Lozama, Anthony; Cunningham, Christopher W.; Caspers, Michael J.; Douglas, Justin T.; Dersch, Christina M.; Rothman, Richard B.; Prisinzano, Thomas E.

2011-01-01

As part of our continuing efforts toward more fully understanding the structure-activity relationships of the neoclerodane diterpene salvinorin A, we report the synthesis and biological characterization of unique cycloadducts through [4+2] Diels-Alder cycloaddition. Microwave-assisted methods were developed and successfully employed, aiding in functionalizing the chemically sensitive salvinorin A scaffold. This demonstrates the first reported results for both cycloaddition of the furan ring and functionalization via microwave-assisted methodology of the salvinorin A skeleton. The cycloadducts yielded herein introduce electron-withdrawing substituents and bulky aromatic groups into the C-12 position. Kappa opioid (KOP) receptor space was explored through aromatization of the bent oxanorbornadiene system possessed by the cycloadducts to a planar phenyl ring system. Although dimethyl- and diethylcarboxylate analogues 5 and 6 retain some affinity and selectivity for KOP receptors and are full agonists, their aromatized counterparts 13 and 14 have reduced affinity for KOP receptors. The methods developed herein signify a novel approach toward rapidly probing the structure-activity relationships of furan containing natural products. PMID:21338114

A discrete mechanics framework for real time virtual surgical simulations with application to virtual laparoscopic nephrectomy.

PubMed

Zhou, Xiangmin; Zhang, Nan; Sha, Desong; Shen, Yunhe; Tamma, Kumar K; Sweet, Robert

2009-01-01

The inability to render realistic soft-tissue behavior in real time has remained a barrier to face and content aspects of validity for many virtual reality surgical training systems. Biophysically based models are not only suitable for training purposes but also for patient-specific clinical applications, physiological modeling and surgical planning. When considering the existing approaches for modeling soft tissue for virtual reality surgical simulation, the computer graphics-based approach lacks predictive capability; the mass-spring model (MSM) based approach lacks biophysically realistic soft-tissue dynamic behavior; and the finite element method (FEM) approaches fail to meet the real-time requirement. The present development stems from physics fundamental thermodynamic first law; for a space discrete dynamic system directly formulates the space discrete but time continuous governing equation with embedded material constitutive relation and results in a discrete mechanics framework which possesses a unique balance between the computational efforts and the physically realistic soft-tissue dynamic behavior. We describe the development of the discrete mechanics framework with focused attention towards a virtual laparoscopic nephrectomy application.

Synchronized dynamics of bacterial niche-specific functions during biofilm development in a cold seep brine pool.

PubMed

Zhang, Weipeng; Wang, Yong; Bougouffa, Salim; Tian, Renmao; Cao, Huiluo; Li, Yongxin; Cai, Lin; Wong, Yue Him; Zhang, Gen; Zhou, Guowei; Zhang, Xixiang; Bajic, Vladimir B; Al-Suwailem, Abdulaziz; Qian, Pei-Yuan

2015-10-01

The biology of biofilm in deep-sea environments is barely being explored. Here, biofilms were developed at the brine pool (characterized by limited carbon sources) and the normal bottom water adjacent to Thuwal cold seeps. Comparative metagenomics based on 50 Gb datasets identified polysaccharide degradation, nitrate reduction and proteolysis as enriched functional categories for brine biofilms. The genomes of two dominant species: a novel Deltaproteobacterium and a novel Epsilonproteobacterium in the brine biofilms were reconstructed. Despite rather small genome sizes, the Deltaproteobacterium possessed enhanced polysaccharide fermentation pathways, whereas the Epsilonproteobacterium was a versatile nitrogen reactor possessing nar, nap and nif gene clusters. These metabolic functions, together with specific regulatory and hypersaline-tolerant genes, made the two bacteria unique compared with their close relatives, including those from hydrothermal vents. Moreover, these functions were regulated by biofilm development, as both the abundance and the expression level of key functional genes were higher in later stage biofilms, and co-occurrences between the two dominant bacteria were demonstrated. Collectively, unique mechanisms were revealed: (i) polysaccharides fermentation, proteolysis interacted with nitrogen cycling to form a complex chain for energy generation, and (ii) remarkably exploiting and organizing niche-specific functions would be an important strategy for biofilm-dependent adaptation to the extreme conditions. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

Management implications of the ecology of free-roaming horses in semiarid ecosystems of the western United States

USGS Publications Warehouse

Beever, Erik

2003-01-01

Compared to other ungulates of North America, free-roaming horses (Equus caballus) possess a unique evolutionary history that has given rise to a distinct suite of behavioral, morphological, and physiological traits. Because of their unique combination of cecal digestion, an elongate head with flexible lips, and non-uniform use of the landscape, horses represent a unique disturbance agent in semi-arid ecosystems of the western United States. Consequently, it is inappropriate to assume that influences of horses on the structure, composition, function, and pattern of arid and semi-arid ecosystems will mirror influences of cattle or other artiodactyls. Although management areas for free-roaming horses occupy 18.6 million ha of land across western North America, we know relatively little about how western ecosystems and their components have responded to this uniquely managed ungulate. I draw on my research of horse habitats in the western Great Basin (U.S.A.) to examine predictions of horses' unique influence, and advocate for continued research to refine our understanding of synecological relationships among horses and diverse ecosystem components in arid and semi-arid regions. 

Fast Batch Production of High-Quality Graphene Films in a Sealed Thermal Molecular Movement System.

PubMed

Xu, Jianbao; Hu, Junxiong; Li, Qi; Wang, Rubing; Li, Weiwei; Guo, Yufen; Zhu, Yongbo; Liu, Fengkui; Ullah, Zaka; Dong, Guocai; Zeng, Zhongming; Liu, Liwei

2017-07-01

Chemical vapor deposition (CVD) growth of high-quality graphene has emerged as the most promising technique in terms of its integrated manufacturing. However, there lacks a controllable growth method for producing high-quality and a large-quantity graphene films, simultaneously, at a fast growth rate, regardless of roll-to-roll (R2R) or batch-to-batch (B2B) methods. Here, a stationary-atmospheric-pressure CVD (SAPCVD) system based on thermal molecular movement, which enables fast B2B growth of continuous and uniform graphene films on tens of stacked Cu(111) foils, with a growth rate of 1.5 µm s -1 , is demonstrated. The monolayer graphene of batch production is found to nucleate from arrays of well-aligned domains, and the films possess few defects and exhibit high carrier mobility up to 6944 cm 2 V -1 s -1 at room temperature. The results indicate that the SAPCVD system combined with single-domain Cu(111) substrates makes it possible to realize fast batch-growth of high-quality graphene films, which opens up enormous opportunities to use this unique 2D material for industrial device applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Robust integer and fractional helical modes in the quantum Hall effect

NASA Astrophysics Data System (ADS)

Ronen, Yuval; Cohen, Yonatan; Banitt, Daniel; Heiblum, Moty; Umansky, Vladimir

2018-04-01

Electronic systems harboring one-dimensional helical modes, where spin and momentum are locked, have lately become an important field of their own. When coupled to a conventional superconductor, such systems are expected to manifest topological superconductivity; a unique phase hosting exotic Majorana zero modes. Even more interesting are fractional helical modes, yet to be observed, which open the route for realizing generalized parafermions. Possessing non-Abelian exchange statistics, these quasiparticles may serve as building blocks in topological quantum computing. Here, we present a new approach to form protected one-dimensional helical edge modes in the quantum Hall regime. The novel platform is based on a carefully designed double-quantum-well structure in a GaAs-based system hosting two electronic sub-bands; each tuned to the quantum Hall effect regime. By electrostatic gating of different areas of the structure, counter-propagating integer, as well as fractional, edge modes with opposite spins are formed. We demonstrate that, due to spin protection, these helical modes remain ballistic over large distances. In addition to the formation of helical modes, this platform can serve as a rich playground for artificial induction of compounded fractional edge modes, and for construction of edge-mode-based interferometers.

Renal dendritic cells sample blood-borne antigen and guide T-cell migration to the kidney by means of intravascular processes.

PubMed

Yatim, Karim M; Gosto, Minja; Humar, Rishab; Williams, Amanda L; Oberbarnscheidt, Martin H

2016-10-01

Bony fish are among the first vertebrates to possess an innate and adaptive immune system. In these species, the kidney has a dual function: filtering solutes similar to mammals and acting as a lymphoid organ responsible for hematopoiesis and antigen processing. Recent studies have shown that the mammalian kidney has an extensive network of mononuclear phagocytes, whose function is not fully understood. Here, we employed two-photon intravital microscopy of fluorescent reporter mice to demonstrate that renal dendritic cells encase the microvasculature in the cortex, extend dendrites into the peritubular capillaries, and sample the blood for antigen. We utilized a mouse model of systemic bacterial infection as well as immune complexes to demonstrate antigen uptake by renal dendritic cells. As a consequence, renal dendritic cells mediated T-cell migration into the kidney in an antigen-dependent manner in the setting of bacterial infection. Thus, renal dendritic cells may be uniquely positioned to play an important role not only in surveillance of systemic infection but also in local infection and autoimmunity. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Two Distinct RNase Activities of CRISPR-C2c2 Enable Guide RNA Processing and RNA Detection

PubMed Central

East-Seletsky, Alexandra; O’Connell, Mitchell R.; Knight, Spencer C.; Burstein, David; Cate, Jamie H. D.; Tjian, Robert; Doudna, Jennifer A.

2017-01-01

Bacterial adaptive immune systems employ CRISPRs (clustered regularly interspaced short palindromic repeats) and CRISPR-associated (Cas) proteins for RNA-guided nucleic acid cleavage1,2. Although generally targeted to DNA substrates3–5, the Type III and Type VI CRISPR systems direct interference complexes against single-stranded RNA (ssRNA) substrates6–9. In Type VI systems, the single-subunit C2c2 protein functions as an RNA-guided RNA endonuclease9,10. How this enzyme acquires mature CRISPR RNAs (crRNAs) essential for immune surveillance and its mechanism of crRNA-mediated RNA cleavage remain unclear. Here we show that C2c2 possesses a unique ribonuclease activity responsible for CRISPR RNA maturation that is distinct from its RNA-activated ssRNA-degradation activity. These dual ribonuclease functions are chemically and mechanistically different from each other and from the crRNA-processing behavior of the evolutionarily unrelated CRISPR enzyme Cpf111. We show that the two ribonuclease activities of C2c2 enable multiplexed processing and loading of guide RNAs that in turn allow for sensitive cellular transcript detection. PMID:27669025

Experimental program for the operational study of data collection platforms in Bolivia

NASA Technical Reports Server (NTRS)

1977-01-01

The system developed for the SMS/GOES satellite while learning the limitations possessed by this system with regard to the LANDSAT 1 and 2 satellites with respect to the transmission distance and horizon angle is investigated. The advantages possessed by this system in comparison with conventional methods are evaluated so as to permit studying the feasibility of introducing it into this country in the near future.

Corrosion-resistant high-entropy alloys: A review

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

Shi, Yunzhu; Yang, Bin; Liaw, Peter

Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs) possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods onmore » the corrosion resistance are analyzed in detail. Finally, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.« less

Corrosion-resistant high-entropy alloys: A review

DOE PAGES

Shi, Yunzhu; Yang, Bin; Liaw, Peter

2017-02-05

Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs) possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods onmore » the corrosion resistance are analyzed in detail. Finally, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.« less

Chinese ethnic meat products: Continuity and development.

PubMed

Zeng, Weicai; Wen, Wenting; Deng, Yue; Tian, Yuanyuan; Sun, Honghu; Sun, Qun

2016-10-01

With their distinctive sensory characterizations and unique processing technologies, Chinese ethnic meat products possess great potential for development and continuity in modern China's meat industry. Due to the greater demand for meat products and higher quality and safety concerns in economically fast growing China, the development and continuity of ethnic meat products face its own unique challenges. In this review, the classification of typical ethnic products and their characteristics, and the research progress on their quality and processing technologies are discussed. The application of innovative and green technologies to improve the safety and quality of ethnic meat products for greater industrialization and sustainable development is highlighted. Furthermore, the strategy for promoting the production of Chinese ethnic meat products during the next five years is presented. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evolution of Fish-Shaped Reptiles (reptilia: Ichthyopterygia) in Their Physical Environments and Constraints

NASA Astrophysics Data System (ADS)

Motani, Ryosuke

2005-01-01

Ichthyosaurs were a group of Mesozoic marine reptiles that evolved fish-shaped body outlines. They are unique in several anatomical characters, including the possession of enormous eyeballs sometimes exceeding 25 cm and an enlarged manus with sometimes up to 20 bones in a single digit, or 10 digits per manus. They are also unique in that their biology has been studied from the perspective of physical constraints, which allowed estimation of such characteristics as optimal cruising speed, visual sensitivity, and even possible basal metabolic rate ranges. These functional inferences, although based on physical principles, obviously contain errors arising from the limitations of fossilized data, but are necessarily stronger than the commonly made inferences based on superficial correlations among quantities without mechanical or optical explanations for why such correlations exist.

The X-ray Crystallographic Structure and Activity Analysis of a Pseudomonas-Specific Subfamily of the HAD Enzyme Superfamily Evidences a Novel Biochemical Function

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

Peisach,E.; Wang, L.; Burroughs, A.

2008-01-01

The haloacid dehalogenase (HAD) superfamily is a large family of proteins dominated by phosphotransferases. Thirty-three sequence families within the HAD superfamily (HADSF) have been identified to assist in function assignment. One such family includes the enzyme phosphoacetaldehyde hydrolase (phosphonatase). Phosphonatase possesses the conserved Rossmanniod core domain and a C1-type cap domain. Other members of this family do not possess a cap domain and because the cap domain of phosphonatase plays an important role in active site desolvation and catalysis, the function of the capless family members must be unique. A representative of the capless subfamily, PSPTO{_}2114, from the plant pathogenmore » Pseudomonas syringae, was targeted for catalytic activity and structure analyses. The X-ray structure of PSPTO{_}2114 reveals a capless homodimer that conserves some but not all of the intersubunit contacts contributed by the core domains of the phosphonatase homodimer. The region of the PSPTO{_}2114 that corresponds to the catalytic scaffold of phosphonatase (and other HAD phosphotransfereases) positions amino acid residues that are ill suited for Mg+2 cofactor binding and mediation of phosphoryl group transfer between donor and acceptor substrates. The absence of phosphotransferase activity in PSPTO{_}2114 was confirmed by kinetic assays. To explore PSPTO{_}2114 function, the conservation of sequence motifs extending outside of the HADSF catalytic scaffold was examined. The stringently conserved residues among PSPTO{_}2114 homologs were mapped onto the PSPTO{_}2114 three-dimensional structure to identify a surface region unique to the family members that do not possess a cap domain. The hypothesis that this region is used in protein-protein recognition is explored to define, for the first time, HADSF proteins which have acquired a function other than that of a catalyst. Proteins 2008.« less

26 CFR 1.937-3 - Income effectively connected with the conduct of a trade or business in a possession.

Code of Federal Regulations, 2013 CFR

2013-04-01

... bona fide resident of Possession I, a section 931 possession (as defined in § 1.931-1(c)(1)). X has an... specialized computer software. A purchaser of software will frequently pay X an additional amount to install the software on the purchaser's operating system and to ensure that the software is functioning...

26 CFR 1.937-3 - Income effectively connected with the conduct of a trade or business in a possession.

Code of Federal Regulations, 2012 CFR

2012-04-01

... bona fide resident of Possession I, a section 931 possession (as defined in § 1.931-1(c)(1)). X has an... specialized computer software. A purchaser of software will frequently pay X an additional amount to install the software on the purchaser's operating system and to ensure that the software is functioning...

26 CFR 1.937-3 - Income effectively connected with the conduct of a trade or business in a possession.

Code of Federal Regulations, 2011 CFR

2011-04-01

... bona fide resident of Possession I, a section 931 possession (as defined in § 1.931-1(c)(1)). X has an... specialized computer software. A purchaser of software will frequently pay X an additional amount to install the software on the purchaser's operating system and to ensure that the software is functioning...

26 CFR 1.937-3 - Income effectively connected with the conduct of a trade or business in a possession.

Code of Federal Regulations, 2014 CFR

2014-04-01

... bona fide resident of Possession I, a section 931 possession (as defined in § 1.931-1(c)(1)). X has an... specialized computer software. A purchaser of software will frequently pay X an additional amount to install the software on the purchaser's operating system and to ensure that the software is functioning...

Using model based systems engineering for the development of the Large Synoptic Survey Telescope's operational plan

NASA Astrophysics Data System (ADS)

Selvy, Brian M.; Claver, Charles; Willman, Beth; Petravick, Don; Johnson, Margaret; Reil, Kevin; Marshall, Stuart; Thomas, Sandrine; Lotz, Paul; Schumacher, German; Lim, Kian-Tat; Jenness, Tim; Jacoby, Suzanne; Emmons, Ben; Axelrod, Tim

2016-08-01

We† provide an overview of the Model Based Systems Engineering (MBSE) language, tool, and methodology being used in our development of the Operational Plan for Large Synoptic Survey Telescope (LSST) operations. LSST's Systems Engineering (SE) team is using a model-based approach to operational plan development to: 1) capture the topdown stakeholders' needs and functional allocations defining the scope, required tasks, and personnel needed for operations, and 2) capture the bottom-up operations and maintenance activities required to conduct the LSST survey across its distributed operations sites for the full ten year survey duration. To accomplish these complimentary goals and ensure that they result in self-consistent results, we have developed a holistic approach using the Sparx Enterprise Architect modeling tool and Systems Modeling Language (SysML). This approach utilizes SysML Use Cases, Actors, associated relationships, and Activity Diagrams to document and refine all of the major operations and maintenance activities that will be required to successfully operate the observatory and meet stakeholder expectations. We have developed several customized extensions of the SysML language including the creation of a custom stereotyped Use Case element with unique tagged values, as well as unique association connectors and Actor stereotypes. We demonstrate this customized MBSE methodology enables us to define: 1) the rolls each human Actor must take on to successfully carry out the activities associated with the Use Cases; 2) the skills each Actor must possess; 3) the functional allocation of all required stakeholder activities and Use Cases to organizational entities tasked with carrying them out; and 4) the organization structure required to successfully execute the operational survey. Our approach allows for continual refinement utilizing the systems engineering spiral method to expose finer levels of detail as necessary. For example, the bottom-up, Use Case-driven approach will be deployed in the future to develop the detailed work procedures required to successfully execute each operational activity.

The unique radar scattering properties of silicic lava flows and domes

NASA Technical Reports Server (NTRS)

Plaut, Jeffrey J.; Stofan, Ellen R.; Anderson, Steven W.; Crown, David A.

1995-01-01

Silicic (silica-rich) lava flows, such as rhyolite, rhyodacite, and dacite, possess unique physical properties primarily because of the relatively high viscosity of the molten lava. Silicic flows tend to be thicker than basaltic flows, and the resulting large-scale morphology is typically a steep-sided dome or flow lobe, with aspect ratios (height/length) sometimes approaching unity. The upper surfaces of silicic domes and flows are normally emplaced as relatively cool, brittle slabs that fracture as they are extruded from the central vent areas, and are then rafted away toward the flow margin as a brittle carapace above a more ductile interior layer. This mode of emplacement results in a surface with unique roughness characteristics, which can be well-characterized by multiparameter synthetic aperture radar (SAR) observations. In this paper, we examine the scattering properties of several silicic domes in the Inyo volcanic chain in the Eastern Sierra of California, using AIRSAR and TOPSAR data. Field measurements of intermediate-scale (cm to tens of m) surface topography and block size are used to assess the mechanisms of the scattering process, and to quantify the unique roughness characteristics of the flow surfaces.

Endophytic fungi: expanding the arsenal of industrial enzyme producers.

PubMed

Corrêa, Rúbia Carvalho Gomes; Rhoden, Sandro Augusto; Mota, Thatiane Rodrigues; Azevedo, João Lúcio; Pamphile, João Alencar; de Souza, Cristina Giatti Marques; Polizeli, Maria de Lourdes Teixeira de Moraes; Bracht, Adelar; Peralta, Rosane Marina

2014-10-01

Endophytic fungi, mostly belonging to the Ascomycota, are found in the intercellular spaces of the aerial plant parts, particularly in leaf sheaths, sometimes even within the bark and root system without inducing any visual symptoms of their presence. These fungi appear to have a capacity to produce a wide range of enzymes and secondary metabolites exhibiting a variety of biological activities. However, they have been only barely exploited as sources of enzymes of industrial interest. This review emphasizes the suitability and possible advantages of including the endophytic fungi in the screening of new enzyme producing organisms as well as in studies aiming to optimize the production of enzymes through well-known culture processes. Apparently endophytic fungi possess the two types of extracellular enzymatic systems necessary to degrade the vegetal biomass: (1) the hydrolytic system responsible for polysaccharide degradation consisting mainly in xylanases and cellulases; and (2) the unique oxidative ligninolytic system, which degrades lignin and opens phenyl rings, comprises mainly laccases, ligninases and peroxidases. The obvious ability of endophytic fungi to degrade the complex structure of lignocellulose makes them useful in the exploration of the lignocellulosic biomass for the production of fuel ethanol and other value-added commodity chemicals. In addition to this, endophytic fungi may become new sources of industrially useful enzymes such as lipases, amylases and proteases.

Artificial “ping-pong” cascade of PIWI-interacting RNA in silkworm cells

PubMed Central

Shoji, Keisuke; Suzuki, Yutaka; Sugano, Sumio; Shimada, Toru; Katsuma, Susumu

2017-01-01

PIWI-interacting RNAs (piRNAs) play essential roles in the defense system against selfish elements in animal germline cells by cooperating with PIWI proteins. A subset of piRNAs is predicted to be generated via the “ping-pong” cascade, which is mainly controlled by two different PIWI proteins. Here we established a cell-based artificial piRNA production system using a silkworm ovarian cultured cell line that is believed to possess a complete piRNA pathway. In addition, we took advantage of a unique silkworm sex-determining one-to-one ping-pong piRNA pair, which enabled us to precisely monitor the behavior of individual artificial piRNAs. With this novel strategy, we successfully generated artificial piRNAs against endogenous protein-coding genes via the expected back-and-forth traveling mechanism. Furthermore, we detected “primary” piRNAs from the upstream region of the artificial “ping-pong” site in the endogenous gene. This artificial piRNA production system experimentally confirms the existence of the “ping-pong” cascade of piRNAs. Also, this system will enable us to identify the factors involved in both, or each, of the “ping” and “pong” cascades and the sequence features that are required for efficient piRNA production. PMID:27777367

Potential Roles of Dental Pulp Stem Cells in Neural Regeneration and Repair

PubMed Central

Luo, Lihua; Wang, Xiaoyan; Key, Brian; Lee, Bae Hoon

2018-01-01

This review summarizes current advances in dental pulp stem cells (DPSCs) and their potential applications in the nervous diseases. Injured adult mammalian nervous system has a limited regenerative capacity due to an insufficient pool of precursor cells in both central and peripheral nervous systems. Nerve growth is also constrained by inhibitory factors (associated with central myelin) and barrier tissues (glial scarring). Stem cells, possessing the capacity of self-renewal and multicellular differentiation, promise new therapeutic strategies for overcoming these impediments to neural regeneration. Dental pulp stem cells (DPSCs) derive from a cranial neural crest lineage, retain a remarkable potential for neuronal differentiation, and additionally express multiple factors that are suitable for neuronal and axonal regeneration. DPSCs can also express immunomodulatory factors that stimulate formation of blood vessels and enhance regeneration and repair of injured nerve. These unique properties together with their ready accessibility make DPSCs an attractive cell source for tissue engineering in injured and diseased nervous systems. In this review, we interrogate the neuronal differentiation potential as well as the neuroprotective, neurotrophic, angiogenic, and immunomodulatory properties of DPSCs and its application in the injured nervous system. Taken together, DPSCs are an ideal stem cell resource for therapeutic approaches to neural repair and regeneration in nerve diseases. PMID:29853908

Duplicated Leptin Receptors in Two Species of Eel Bring New Insights into the Evolution of the Leptin System in Vertebrates

PubMed Central

Morini, Marina; Pasquier, Jérémy; Dirks, Ron; van den Thillart, Guido; Tomkiewicz, Jonna; Rousseau, Karine; Dufour, Sylvie; Lafont, Anne-Gaëlle

2015-01-01

Since its discovery in mammals as a key-hormone in reproduction and metabolism, leptin has been identified in an increasing number of tetrapods and teleosts. Tetrapods possess only one leptin gene, while most teleosts possess two leptin genes, as a result of the teleost third whole genome duplication event (3R). Leptin acts through a specific receptor (LEPR). In the European and Japanese eels, we identified two leptin genes, and for the first time in vertebrates, two LEPR genes. Synteny analyses indicated that eel LEPRa and LEPRb result from teleost 3R. LEPRb seems to have been lost in the teleost lineage shortly after the elopomorph divergence. Quantitative PCRs revealed a wide distribution of leptins and LEPRs in the European eel, including tissues involved in metabolism and reproduction. Noticeably, leptin1 was expressed in fat tissue, while leptin2 in the liver, reflecting subfunctionalization. Four-month fasting had no impact on the expression of leptins and LEPRs in control European eels. This might be related to the remarkable adaptation of silver eel metabolism to long-term fasting throughout the reproductive oceanic migration. In contrast, sexual maturation induced differential increases in the expression of leptins and LEPRs in the BPG-liver axis. Leptin2 was strikingly upregulated in the liver, the central organ of the reproductive metabolic challenge in teleosts. LEPRs were differentially regulated during sexual maturation, which may have contributed to the conservation of the duplicated LEPRs in this species. This suggests an ancient and positive role of the leptin system in the vertebrate reproductive function. This study brings new insights on the evolutionary history of the leptin system in vertebrates. Among extant vertebrates, the eel represents a unique case of duplicated leptins and leptin receptors as a result of 3R. PMID:25946034

Purifying Selection Maintains Dosage-Sensitive Genes during Degeneration of the Threespine Stickleback Y Chromosome

PubMed Central

White, Michael A.; Kitano, Jun; Peichel, Catherine L.

2015-01-01

Sex chromosomes are subject to unique evolutionary forces that cause suppression of recombination, leading to sequence degeneration and the formation of heteromorphic chromosome pairs (i.e., XY or ZW). Although progress has been made in characterizing the outcomes of these evolutionary processes on vertebrate sex chromosomes, it is still unclear how recombination suppression and sequence divergence typically occur and how gene dosage imbalances are resolved in the heterogametic sex. The threespine stickleback fish (Gasterosteus aculeatus) is a powerful model system to explore vertebrate sex chromosome evolution, as it possesses an XY sex chromosome pair at relatively early stages of differentiation. Using a combination of whole-genome and transcriptome sequencing, we characterized sequence evolution and gene expression across the sex chromosomes. We uncovered two distinct evolutionary strata that correspond with known structural rearrangements on the Y chromosome. In the oldest stratum, only a handful of genes remain, and these genes are under strong purifying selection. By comparing sex-linked gene expression with expression of autosomal orthologs in an outgroup, we show that dosage compensation has not evolved in threespine sticklebacks through upregulation of the X chromosome in males. Instead, in the oldest stratum, the genes that still possess a Y chromosome allele are enriched for genes predicted to be dosage sensitive in mammals and yeast. Our results suggest that dosage imbalances may have been avoided at haploinsufficient genes by retaining function of the Y chromosome allele through strong purifying selection. PMID:25818858

Functional Properties of Microorganisms in Fermented Foods

PubMed Central

Tamang, Jyoti P.; Shin, Dong-Hwa; Jung, Su-Jin; Chae, Soo-Wan

2016-01-01

Fermented foods have unique functional properties imparting some health benefits to consumers due to presence of functional microorganisms, which possess probiotics properties, antimicrobial, antioxidant, peptide production, etc. Health benefits of some global fermented foods are synthesis of nutrients, prevention of cardiovascular disease, prevention of cancer, gastrointestinal disorders, allergic reactions, diabetes, among others. The present paper is aimed to review the information on some functional properties of the microorganisms associated with fermented foods and beverages, and their health-promoting benefits to consumers. PMID:27199913

Synthesis of 2,2,4,4-tetramethyl-N,N'-bis(2,6-dimethylphenyl)cyclobutane-1,3-diimine , a unique compound from Arundo donax, and its analogues to test their antifeedant activity against the boll weevil, Anthonomus grandis.

PubMed

Mochizuki, K; Takikawa, H; Mori, K

2000-03-01

2,2,4,4-Tetramethyl-N,N'-bis(2,6-dimethylphenyl) cyclobutane-1,3-diimine (1), which was isolated from the Thai plant Arundo donax as an antifeedant against the boll weevil (Anthonomus grandis), and its analogues (9-13) were synthesized and shown to possess no remarkable antifeedant activity of practical interest.

Isopalhinine A, a unique pentacyclic Lycopodium alkaloid from Palhinhaea cernua.

PubMed

Dong, Liao-Bin; Gao, Xiu; Liu, Fei; He, Juan; Wu, Xing-De; Li, Yan; Zhao, Qin-Shi

2013-07-19

A new pentacyclic (5/6/6/6/7) Lycopodium alkaloid named isopalhinine A (1), which possesses a sterically congested architecture built with a tricyclo[4.3.1.0(3,7)]decane (isotwistane) moiety and a 1-azabicyclo[4.3.1]decane moiety, and palhinines B (2) and C (3) were isolated from Palhinhaea cernua. The structure and absolute configuration of 1 were elucidated by a combination of NMR spectra, optical rotation calculation, and X-ray diffraction experiment. A possible biogenetic pathway was also proposed.

Anilinomethylrhodamines: pH sensitive probes with tunable photophysical properties by substituent effect.

PubMed

Best, Quinn A; Liu, Chuangjun; van Hoveln, Paul D; McCarroll, Matthew E; Scott, Colleen N

2013-10-18

A series of pH dependent rhodamine analogues possessing an anilino-methyl moiety was developed and shown to exhibit a unique photophysical response to pH. These anilinomethylrhodamines (AnMR) maintain a colorless, nonfluorescent spirocyclic structure at high pH. The spirocyclic structures open in mildly acidic conditions and are weakly fluorescent; however, at very low pH, the fluorescence is greatly enhanced. The equilibrium constants of these processes show a linear response to substituent effects, which was demonstrated by the Hammett equation.

Self-organized, highly luminescent CdSe nanorod-DNA complexes.

PubMed

Artemyev, Mikhail; Kisiel, Dmitry; Abmiotko, Sergey; Antipina, Maria N; Khomutov, Gennady B; Kislov, Vladimir V; Rakhnyanskaya, Anna A

2004-09-01

DNA molecules are useful building blocks and nanotemplates for controllable fabrication of various bioinorganic nanostructures due to their unique physical-chemical properties and recognition capabilities and the synthetic availability of desired nucleotide sequences and length. We have synthesized novel DNA complexes with positively charged, highly luminescent CdSe nanorods that can be self-organized into filamentary, netlike, or spheroidal nanostructures. DNA-CdSe-nanorod filaments possess strongly linearly polarized photoluminescence due to the unidirectional orientation of nanorods along the filaments. Copyright 2004 American Chemical Society

Implications of recent new concepts on the future of mainstream laser processing

NASA Astrophysics Data System (ADS)

La Rocca, Aldo V.

2000-07-01

According to one of today's most accepted visualizations of the first viable realizations of The Computer Integrated Manufacturing Plant, C.I.M.P., the manufacturing systems herein discussed tend to be multiprocessing, and tend to incorporate the lasers to take advantage of the unique capacities of the laser as a processing tool. Finally also the present laser sources, while having been for a long time more than sufficient, inevitably tend also to new generations. Said visualizations stand in the belief that the first realizations of the C I M P most likely will use flexible multiprocessing machines, which, for flexibility requirements, grow in multi-station cells, in their aggregation in isles and finally in complete manufacturing centers. To constitute the CIMP all partaking elements must be the most easily amenable to Computer Aided Design, CAD, and Computer Aided Manufacturing, CAM. Another basic requirement is that all elements constituting the CIMP must possess the highest System Efficiency and Energy Efficiency at the level of the single element and of its aggregations throughout the various combinations at each and every operating level of said aggregations, up to that of the CIMP. The mastering of the CIMP design constitute a New Discipline that presents very formidable but necessary tasks. Of these the first examples were those related to the early flexible manufacturing system Design Programs. For what concerns the laser processing machines and their integration in manufacturing systems, attention must be given to not repeat the events that hindered their diffusion in the production field keeping it at a level much lower than the expectations and their true potential. Said events stemmed from the confusion between System Efficiency and Energy Efficiency, which persisted for too long and is still common. This has taken place at the levels of introduction of a single element into the combination of the several elements constituting a linear arrangement such as a Transfer Production Line. It because greater and with graver consequences in the case of arrangements possessing more than one degree of product routings, arrangements, as previously mentioned, which evolved in the Flexible Manufacturing Centers.

Can soft biometric traits assist user recognition?

NASA Astrophysics Data System (ADS)

Jain, Anil K.; Dass, Sarat C.; Nandakumar, Karthik

2004-08-01

Biometrics is rapidly gaining acceptance as the technology that can meet the ever increasing need for security in critical applications. Biometric systems automatically recognize individuals based on their physiological and behavioral characteristics. Hence, the fundamental requirement of any biometric recognition system is a human trait having several desirable properties like universality, distinctiveness, permanence, collectability, acceptability, and resistance to circumvention. However, a human characteristic that possesses all these properties has not yet been identified. As a result, none of the existing biometric systems provide perfect recognition and there is a scope for improving the performance of these systems. Although characteristics like gender, ethnicity, age, height, weight and eye color are not unique and reliable, they provide some information about the user. We refer to these characteristics as "soft" biometric traits and argue that these traits can complement the identity information provided by the primary biometric identifiers like fingerprint and face. This paper presents the motivation for utilizing soft biometric information and analyzes how the soft biometric traits can be automatically extracted and incorporated in the decision making process of the primary biometric system. Preliminary experiments were conducted on a fingerprint database of 160 users by synthetically generating soft biometric traits like gender, ethnicity, and height based on known statistics. The results show that the use of additional soft biometric user information significantly improves (approximately 6%) the recognition performance of the fingerprint biometric system.

[Forensic hematology genetics--paternity testing].

PubMed

Kratzer, A; Bär, W

1997-05-01

In Switzerland paternity investigations are carried out using DNA analysis only since 1991. DNA patterns are inherited and only with the exception of genetically identical twins they are different in everyone and therefore unique to an individual. Hence DNA-systems are an excellent tool to resolve paternity disputes. DNA polymorphisms used for paternity diagnosis are length polymorphisms of the highly polymorphic VNTR loci [variable number of tandem repeats]. The most frequently applied systems are the DNA single locus systems. In addition to the DNA single locus systems the application of PCR (PCR = polymerase chain reaction) based DNA systems has increased particularly in difficult deficiency cases or in cases where only small evidential samples or partially degraded DNA are available. Normally four independent DNA single probes are used to produce a DNA profile from the mother, the child and the alleged father. A child inherits half the DNA patterns from its mother and the other half from its true biological father. If an alleged father doesn't possess the paternal specific DNA pattern in his DNA profile he is excluded from the paternity. In case of non-exclusion the probability for paternity is calculated according to Essen-Möller. When applying four highly polymorphic DNA single locus systems the biostatistical evaluation leads always to W-values exceeding 99.8% [= required value for positive proof of paternity]. DNA analysis is currently the best available method to achieve such effective conclusions in paternity investigations.

Bat Biology, Genomes, and the Bat1K Project: To Generate Chromosome-Level Genomes for All Living Bat Species.

PubMed

Teeling, Emma C; Vernes, Sonja C; Dávalos, Liliana M; Ray, David A; Gilbert, M Thomas P; Myers, Eugene

2018-02-15

Bats are unique among mammals, possessing some of the rarest mammalian adaptations, including true self-powered flight, laryngeal echolocation, exceptional longevity, unique immunity, contracted genomes, and vocal learning. They provide key ecosystem services, pollinating tropical plants, dispersing seeds, and controlling insect pest populations, thus driving healthy ecosystems. They account for more than 20% of all living mammalian diversity, and their crown-group evolutionary history dates back to the Eocene. Despite their great numbers and diversity, many species are threatened and endangered. Here we announce Bat1K, an initiative to sequence the genomes of all living bat species (n∼1,300) to chromosome-level assembly. The Bat1K genome consortium unites bat biologists (>148 members as of writing), computational scientists, conservation organizations, genome technologists, and any interested individuals committed to a better understanding of the genetic and evolutionary mechanisms that underlie the unique adaptations of bats. Our aim is to catalog the unique genetic diversity present in all living bats to better understand the molecular basis of their unique adaptations; uncover their evolutionary history; link genotype with phenotype; and ultimately better understand, promote, and conserve bats. Here we review the unique adaptations of bats and highlight how chromosome-level genome assemblies can uncover the molecular basis of these traits. We present a novel sequencing and assembly strategy and review the striking societal and scientific benefits that will result from the Bat1K initiative.

If technological intelligent extraterrestrials exist, what biological traits are de rigueur

NASA Astrophysics Data System (ADS)

Taylor, E. R.

2018-05-01

If extraterrestrials exist in the depths of cosmic space, and are capable of interstellar communications, even space flight, there is no requirement that they be humanoid in form. However, certain humanoid capabilities would be advantageous for tool fashioning and critical to operating space craft as well as functioning under the disparate extreme conditions under which they may be forced to operate. They would have to be "gas breathing". The reasonable assumption that life based upon the same elements as Earth life requiring water stems from the unique properties of water that no other similar low molecular weight nonmetal hydride offers. Only water offers the diversity of chemical properties and reactivity, including the existence of the three common physical states within a limited temperature range of service to life, avoiding the issues presented by any alternatives. They must, like us, possess a large, abstract-thinking brain, and probably possess at least all the fundamental senses that humankind possess. They would also be carbon-based life, using oxygen as the electron sink of their biochemistry for the reasons considered. They most likely are homeothermic as us, though they may not necessarily be mammalian as we are. Their biochemistry could differ some from ours, perhaps presenting contact hazards for both species as discussed.

Ameloblasts express type I collagen during amelogenesis.

PubMed

Assaraf-Weill, N; Gasse, B; Silvent, J; Bardet, C; Sire, J Y; Davit-Béal, T

2014-05-01

Enamel and enameloid, the highly mineralized tooth-covering tissues in living vertebrates, are different in their matrix composition. Enamel, a unique product of ameloblasts, principally contains enamel matrix proteins (EMPs), while enameloid possesses collagen fibrils and probably receives contributions from both odontoblasts and ameloblasts. Here we focused on type I collagen (COL1A1) and amelogenin (AMEL) gene expression during enameloid and enamel formation throughout ontogeny in the caudate amphibian, Pleurodeles waltl. In this model, pre-metamorphic teeth possess enameloid and enamel, while post-metamorphic teeth possess enamel only. In first-generation teeth, qPCR and in situ hybridization (ISH) on sections revealed that ameloblasts weakly expressed AMEL during late-stage enameloid formation, while expression strongly increased during enamel deposition. Using ISH, we identified COL1A1 transcripts in ameloblasts and odontoblasts during enameloid formation. COL1A1 expression in ameloblasts gradually decreased and was no longer detected after metamorphosis. The transition from enameloid-rich to enamel-rich teeth could be related to a switch in ameloblast activity from COL1A1 to AMEL synthesis. P. waltl therefore appears to be an appropriate animal model for the study of the processes involved during enameloid-to-enamel transition, especially because similar events probably occurred in various lineages during vertebrate evolution.

Implementing traceability using particle randomness-based textile printed tags

NASA Astrophysics Data System (ADS)

Agrawal, T. K.; Koehl, L.; Campagne, C.

2017-10-01

This article introduces a random particle-based traceability tag for textiles. The proposed tag not only act as a unique signature for the corresponding textile product but also possess the features such as easy to manufacture and hard to copy. It seeks applications in brand authentication and traceability in textile and clothing (T&C) supply chain. A prototype has been developed by screen printing process, in which micron-scale particles were mixed with the printing paste and printed on cotton fabrics to attain required randomness. To encode the randomness, the image of the developed tag was taken and analyzed using image processing. The randomness of the particles acts as a product key or unique signature which is required to decode the tag. Finally, washing and abrasion resistance tests were conducted to check the durability of the printed tag.

Sociolinguistic awareness and false belief in young Cantonese learners of English.

PubMed

Cheung, Him; Mak, Wing Yan; Luo, Xueying; Xiao, Wen

2010-10-01

In this study, we examined whether sociolinguistic awareness and false belief were uniquely related in 3- and 4-year-old Cantonese-speaking children learning English as a second language. The English-use background of these children varied so that they possessed sociolinguistic awareness to different degrees. Results indicated that sociolinguistic awareness predicted false belief uniquely after controlling for age, nonverbal intelligence, English vocabulary, and family income for both the second language learners and the more balanced bilinguals. The group difference in false belief was adequately explained by the corresponding difference in sociolinguistic awareness over and above the other variables. Such findings provide evidence for the claim that false belief understanding is critically related to sociolinguistic awareness, which in turn is influenced by how a second language is learned. Copyright 2010 Elsevier Inc. All rights reserved.

C1q/TNF-related Protein 4 (CTRP4) Is a Unique Secreted Protein with Two Tandem C1q Domains That Functions in the Hypothalamus to Modulate Food Intake and Body Weight*

PubMed Central

Byerly, Mardi S.; Petersen, Pia S.; Ramamurthy, Santosh; Seldin, Marcus M.; Lei, Xia; Provost, Elayne; Wei, Zhikui; Ronnett, Gabriele V.; Wong, G. William

2014-01-01

CTRP4 is a unique member of the C1q family, possessing two tandem globular C1q domains. Its physiological function is poorly defined. Here, we show that CTRP4 is an evolutionarily conserved, ∼34-kDa secretory protein expressed in the brain. In human, mouse, and zebrafish brain, CTRP4 expression begins early in development and is widespread in the central nervous system. Neurons, but not astrocytes, express and secrete CTRP4, and secreted proteins form higher-order oligomeric complexes. CTRP4 is also produced by peripheral tissues and circulates in blood. Its serum levels are increased in leptin-deficient obese (ob/ob) mice. Functional studies suggest that CTRP4 acts centrally to modulate energy metabolism. Refeeding following an overnight fast induced the expression of CTRP4 in the hypothalamus. Central administration of recombinant protein suppressed food intake and altered the whole-body energy balance in both chow-fed and high-fat diet-fed mice. Suppression of food intake by CTRP4 is correlated with a decreased expression of orexigenic neuropeptide (Npy and Agrp) genes in the hypothalamus. These results establish CTRP4 as a novel nutrient-responsive central regulator of food intake and energy balance. PMID:24366864

Sensitive SERS detection of lead ions via DNAzyme based quadratic signal amplification.

PubMed

Tian, Aihua; Liu, Yu; Gao, Jian

2017-08-15

Highly sensitive detection of Pb 2+ is very necessary for water quality control, clinical toxicology, and industrial monitoring. In this work, a simple and novel DNAzyme-based SERS quadratic amplification method is developed for the detection of Pb 2+ . This strategy possesses some remarkable features compared to the conventional DNAzyme-based SERS methods, which are as follows: (i) Coupled DNAzyme-activated hybridization chain reaction (HCR) with bio barcodes; a quadratic amplification method is designed using the unique catalytic selectivity of DNAzyme. The SERS signal is significantly amplified. This method is rapid with a detection time of 2h. (ii) The problem of high background induced by excess bio barcodes is circumvented by using magnetic beads (MBs) as the carrier of signal-output products, and this sensing system is simple in design and can easily be carried out by simple mixing and incubation. Given the unique and attractive characteristics, a simple and universal strategy is designed to accomplish sensitive detection of Pb 2+ . The detection limit of Pb 2+ via SERS detection is 70 fM, with the linear range from 1.0×10 -13 M to 1.0×10 -7 M. The method can be further extended to the quantitative detection of a variety of targets by replacing the lead-responsive DNAzyme with other functional DNA. Copyright © 2017 Elsevier B.V. All rights reserved.

Crystal Structure and Oligomeric State of the RetS Signaling Kinase Sensory Domain

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

Jing, X.; Jaw, J; Robinson, H

2010-01-01

The opportunistic pathogen Pseudomonas aeruginosa may cause both acute and chronic-persistent infections in predisposed individuals. Acute infections require the presence of a functional type III secretion system (T3SS), whereas chronic P. aeruginosa infections are characterized by the formation of drug-resistant biofilms. The T3SS and biofilm formation are reciprocally regulated by the signaling kinases LadS, RetS, and GacS. RetS downregulates biofilm formation and upregulates expression of the T3SS through a unique mechanism. RetS forms a heterodimeric complex with GacS and thus prevents GacS autophosphorylation and downstream signaling. The signals that regulate RetS are not known but RetS possesses a distinctive periplasmicmore » sensor domain that is believed to serve as receptor for the regulatory ligand. We have determined the crystal structure of the RetS sensory domain at 2.0 {angstrom} resolution. The structure closely resembles those of carbohydrate binding modules of other proteins, suggesting that the elusive ligands are likely carbohydrate moieties. In addition to the conserved beta-sandwich structure, the sensory domain features two alpha helices which create a unique surface topology. Protein-protein crosslinking and fluorescence energy transfer experiments also revealed that the sensory domain dimerizes with a dissociation constant of K{sub d} = 580 {+-} 50 nM, a result with interesting implications for our understanding of the underlying signaling mechanism.« less

Pharmaceutical sales of pseudoephedrine: the impact of electronic tracking systems on methamphetamine crime incidents.

PubMed

Mazerolle, Lorraine; McGuffog, Ingrid; Ferris, Jason; Chamlin, Mitchell B

2017-03-01

Electronic tracking systems (ETS) are used extensively in pharmacies across the United States and Australia to control suspicious sales of pseudoephedrine. This study measures the impact of one ETS-Project STOP-on the capacity of police to reduce production, supply and possession of methamphetamine. Using official police data of incidents of production, supply and possession from January 1996 to December 2011 (n = 192 data points/months over 16 years), we used a quasi-experimental, time-series approach. The State of Queensland, Australia. No individual participants are included in the study. The unit of analysis is reported police incidents. The study examines the impact of the ETS on production (n = 5938 incidents), drug supply and trafficking (n = 20 094 incidents) and drug possession or use (n = 118 926) of methamphetamine. Introduction of the ETS in November 2005 was associated with an insignificant decrease (P = 0.15) in the production of methamphetamine. The intervention was associated with a statistically significant increase in supply incidents (P = 0.0001). There was no statistically significant effect on the incidence of possession (P = 0.59). Electronic tracking systems can reduce the capacity of people to produce methamphetamine domestically, but seem unlikely to affect other aspects of the methamphetamine problem such as possession, distribution and importation. © 2016 Society for the Study of Addiction.

A unique form of light reflector and the evolution of signalling in Ovalipes (Crustacea: Decapoda: Portunidae)

PubMed Central

Parker, A. R.; Mckenzie, D. R.; Ahyong, S. T.

1998-01-01

The first demonstration, to our knowledge, of an evolutionary shift in communication mode in animals is presented. Some species of Ovalipes display spectacular iridescence resulting from multilayer reflectors in the cuticle. This reflector is unique in animals because each layer is corrugated and slightly out of phase with adjacent layers. Solid layers are separated from fluid layers in the reflector by side branches acting as support struts. An effect of this reflector is that blue light is reflected over a 'broad' angle around a plane parallel to the sea floor when the host crab is resting. Species of Ovalipes all possess stridulatory structures. The shallow-water species with the best developed stridulatory structures are non-iridescent and use sound as a signal. Deep-water species possess poorly developed stridulatory structures and display iridescence from most regions of the body. In deep water, where incident light is blue, light display is highly directional in contrast to sound produced via stridulation. Sound and light display probably perform the same function of sexual signalling in Ovalipes, although the directional signal is less likely to attract predators. Deep-water species of Ovalipes appear to have evolved towards using light in conspecific signalling. This change from using sound to using light reflects the change in habitat light properties, perhaps the hunting mechanisms of cohabitees, and its progression is an indicator of phylogeny. The changes in sexual signalling mechanisms, following spatial–geographical isolation, may have promoted speciation in Ovalipes.

Current investigations into magnetic nanoparticles for biomedical applications.

PubMed

Li, Xiaoming; Wei, Jianrong; Aifantis, Katerina E; Fan, Yubo; Feng, Qingling; Cui, Fu-Zhai; Watari, Fumio

2016-05-01

It is generally recognized that nanoparticles possess unique physicochemical properties that are largely different from those of conventional materials, specifically the electromagnetic properties of magnetic nanoparticles (MNPs). These properties have attracted many researchers to launch investigations into their potential biomedical applications, which have been reviewed in this article. First, common types of MNPs were briefly introduced. Then, the biomedical applications of MNPs were reviewed in seven parts: magnetic resonance imaging (MRI), cancer therapy, the delivery of drugs and genes, bone and dental repair, tissue engineering, biosensors, and in other aspects, which indicated that MNPs possess great potentials for many kinds of biomedical applications due to their unique properties. Although lots of achievements have been obtained, there is still a lot of work to do. New synthesis techniques and methods are still needed to develop the MNPs with satisfactory biocompatibility. More effective methods need to be exploited to prepare MNPs-based composites with fine microstructures and high biomedical performances. Other promising research points include the development of more appropriate techniques of experiments both in vitro and in vivo to detect and analyze the biocompatibility and cytotoxicity of MNPs and understand the possible influencing mechanism of the two properties. More comprehensive investigations into the diagnostic and therapeutic applications of composites containing MNPs with "core-shell" structure and deeper understanding and further study into the properties of MNPs to reveal their new biomedical applications, are also described in the conclusion and perspectives part. © 2016 Wiley Periodicals, Inc.

Comparative Functional Genomics of Lactobacillus spp. Reveals Possible Mechanisms for Specialization of Vaginal Lactobacilli to Their Environment

PubMed Central

Suzuki, Haruo; Hickey, Roxana J.; Forney, Larry J.

2014-01-01

Lactobacilli are found in a wide variety of habitats. Four species, Lactobacillus crispatus, L. gasseri, L. iners, and L. jensenii, are common and abundant in the human vagina and absent from other habitats. These may be adapted to the vagina and possess characteristics enabling them to thrive in that environment. Furthermore, stable codominance of multiple Lactobacillus species in a single community is infrequently observed. Thus, it is possible that individual vaginal Lactobacillus species possess unique characteristics that confer to them host-specific competitive advantages. We performed comparative functional genomic analyses of representatives of 25 species of Lactobacillus, searching for habitat-specific traits in the genomes of the vaginal lactobacilli. We found that the genomes of the vaginal species were significantly smaller and had significantly lower GC content than those of the nonvaginal species. No protein families were found to be specific to the vaginal species analyzed, but some were either over- or underrepresented relative to nonvaginal species. We also found that within the vaginal species, each genome coded for species-specific protein families. Our results suggest that even though the vaginal species show no general signatures of adaptation to the vaginal environment, each species has specific and perhaps unique ways of interacting with its environment, be it the host or other microbes in the community. These findings will serve as a foundation for further exploring the role of lactobacilli in the ecological dynamics of vaginal microbial communities and their ultimate impact on host health. PMID:24488312

A decade and a half of protein intrinsic disorder: Biology still waits for physics

PubMed Central

Uversky, Vladimir N

2013-01-01

The abundant existence of proteins and regions that possess specific functions without being uniquely folded into unique 3D structures has become accepted by a significant number of protein scientists. Sequences of these intrinsically disordered proteins (IDPs) and IDP regions (IDPRs) are characterized by a number of specific features, such as low overall hydrophobicity and high net charge which makes these proteins predictable. IDPs/IDPRs possess large hydrodynamic volumes, low contents of ordered secondary structure, and are characterized by high structural heterogeneity. They are very flexible, but some may undergo disorder to order transitions in the presence of natural ligands. The degree of these structural rearrangements varies over a very wide range. IDPs/IDPRs are tightly controlled under the normal conditions and have numerous specific functions that complement functions of ordered proteins and domains. When lacking proper control, they have multiple roles in pathogenesis of various human diseases. Gaining structural and functional information about these proteins is a challenge, since they do not typically “freeze” while their “pictures are taken.” However, despite or perhaps because of the experimental challenges, these fuzzy objects with fuzzy structures and fuzzy functions are among the most interesting targets for modern protein research. This review briefly summarizes some of the recent advances in this exciting field and considers some of the basic lessons learned from the analysis of physics, chemistry, and biology of IDPs. PMID:23553817

Properties of the iron--sulphur proteins of the benzene dioxygenase system from Pseudomonas putida.

PubMed Central

Crutcher, S E; Geary, P J

1979-01-01

A purification procedure was developed to stabilize the iron-sulphur proteins of the benzene dioxygenase system from Pseudomonas putida. The intermediate electron-carrying protein has a mol. wt. of 12300 and possesses one (2Fe--2S) cluster, whereas the terminal dioxygenase has a mol.wt. of 215300 and possesses two (2Fe--2S) clusters. The order and stoicheiometry of electron transfer and of the whole system are described. Images Fig. 2. PMID:435241

Identifying the Evolutionary Building Blocks of the Cardiac Conduction System

PubMed Central

Jensen, Bjarke; Boukens, Bastiaan J. D.; Postma, Alex V.; Gunst, Quinn D.; van den Hoff, Maurice J. B.; Moorman, Antoon F. M.; Wang, Tobias; Christoffels, Vincent M.

2012-01-01

The endothermic state of mammals and birds requires high heart rates to accommodate the high rates of oxygen consumption. These high heart rates are driven by very similar conduction systems consisting of an atrioventricular node that slows the electrical impulse and a His-Purkinje system that efficiently activates the ventricular chambers. While ectothermic vertebrates have similar contraction patterns, they do not possess anatomical evidence for a conduction system. This lack amongst extant ectotherms is surprising because mammals and birds evolved independently from reptile-like ancestors. Using conserved genetic markers, we found that the conduction system design of lizard (Anolis carolinensis and A. sagrei), frog (Xenopus laevis) and zebrafish (Danio rerio) adults is strikingly similar to that of embryos of mammals (mouse Mus musculus, and man) and chicken (Gallus gallus). Thus, in ectothermic adults, the slow conducting atrioventricular canal muscle is present, no fibrous insulating plane is formed, and the spongy ventricle serves the dual purpose of conduction and contraction. Optical mapping showed base-to-apex activation of the ventricles of the ectothermic animals, similar to the activation pattern of mammalian and avian embryonic ventricles and to the His-Purkinje systems of the formed hearts. Mammalian and avian ventricles uniquely develop thick compact walls and septum and, hence, form a discrete ventricular conduction system from the embryonic spongy ventricle. Our study uncovers the evolutionary building plan of heart and indicates that the building blocks of the conduction system of adult ectothermic vertebrates and embryos of endotherms are similar. PMID:22984480

Deoxyribonucleic acid restriction and modification systems in Salmonella: chromosomally located systems of different serotypes.

PubMed Central

Bullas, L R; Colson, C; Neufeld, B

1980-01-01

With the use of four different phages, Salmonella strains representing 85 different serotypes were examined to determine their restriction-modification phenotype. They fell into one of three groups on this basis: group 1, those which lacked the common LT system; group 2, those in which only the LT system could be recognized; and group 3. those which possessed the LT system and at least one other system shown with some serotypes to be closely linked to serB. The specificity of the serB-linked restriction-modification system was unique for each serotype, but different strains of the same serotype expressed the same specificity. Two of the systems were shown to behave in genetic crosses as functional alleles of the S. typhimurium SB system. It is possible that these serB-linked restriction-modification systems constitute a large multiallelic series of genes extending throughout the Salmonella genus and Escherichia coli. We suggest that the division of the Salmonella into the three restriction-modification groups may be significant in defining a "biological grouping" of the different serotypes within the genus which may ultimately be useful in describing the Salmonella species. From the genetic relatedness between the genes of some of the Salmonella restriction-modification systems with those of the E. coli systems, we deduce that the restriction endonuclases produced by the Salmonella serB-linked systems are of type 1. Determination of the nucleotide sequences of the recognition sites of the restriction endonucleases of selected Salmonella systems should further our understanding of specificity with these enzymes. PMID:6243623

Fabrication of highly ordered polyaniline nanocone on pristine graphene for high-performance supercapacitor electrodes

NASA Astrophysics Data System (ADS)

Song, Ningning; Wang, Wucong; Wu, Yue; Xiao, Ding; Zhao, Yaping

2018-04-01

The hybrids of pristine graphene with polyaniline were synthesized by in situ polymerizations for making a high-performance supercapacitor. The formed high-ordered PANI nanocones were vertically aligned on the graphene sheets. The length of the PANI nanocones increased with the concentration of aniline monomer. The specific capacitance of the hybrids electrode in the three-electrode system was measured as high as 481 F/g at a current density of 0.1 A/g, and its stability remained 87% after constant charge-discharge 10000 cycles at a current density of 1 A/g. This outstanding performance is attributed to the coupling effects of the pristine graphene and the hierarchical structure of the PANI possessing high specific surface area. The unique structure of the PANI provided more charge transmission pathways and fast charge-transfer speed of electrons to the pristine graphene because of its large specific area exposed to the electrolyte. The hybrid is expected to have potential applications in supercapacitor electrodes.

Preparation and development of block copolypeptide vesicles and hydrogels for biological and medical applications.

PubMed

Deming, Timothy J

2014-01-01

There have been many recent advances in the controlled polymerization of α-amino acid-N-carboxyanhydride (NCA) monomers into well-defined block copolypeptides. Transition metal initiating systems allow block copolypeptide synthesis with excellent control over number and lengths of block segments, chain length distribution, and chain-end functionality. Using this and other methods, block copolypeptides of controlled dimensions have been prepared and their self-assembly into organized structures studied by many research groups. The ability of well-defined block copolypeptides to assemble into supramolecular copolypeptide vesicles and hydrogels has led to the development of these materials for use in biological and medical applications. These assemblies have been found to possess unique properties that are derived from the amino acid building blocks and ordered conformations of the polypeptide segments. Recent work on the incorporation of active and stimulus-responsive functionality in these materials has tremendously increased their potential for use in biological and medical studies. © 2014 Wiley Periodicals, Inc.

Basic math in monkeys and college students.

PubMed

Cantlon, Jessica F; Brannon, Elizabeth M

2007-12-01

Adult humans possess a sophisticated repertoire of mathematical faculties. Many of these capacities are rooted in symbolic language and are therefore unlikely to be shared with nonhuman animals. However, a subset of these skills is shared with other animals, and this set is considered a cognitive vestige of our common evolutionary history. Current evidence indicates that humans and nonhuman animals share a core set of abilities for representing and comparing approximate numerosities nonverbally; however, it remains unclear whether nonhuman animals can perform approximate mental arithmetic. Here we show that monkeys can mentally add the numerical values of two sets of objects and choose a visual array that roughly corresponds to the arithmetic sum of these two sets. Furthermore, monkeys' performance during these calculations adheres to the same pattern as humans tested on the same nonverbal addition task. Our data demonstrate that nonverbal arithmetic is not unique to humans but is instead part of an evolutionarily primitive system for mathematical thinking shared by monkeys.

Highly efficient targeted mutagenesis in axolotl using Cas9 RNA-guided nuclease

PubMed Central

Flowers, G. Parker; Timberlake, Andrew T.; Mclean, Kaitlin C.; Monaghan, James R.; Crews, Craig M.

2014-01-01

Among tetrapods, only urodele salamanders, such as the axolotl Ambystoma mexicanum, can completely regenerate limbs as adults. The mystery of why salamanders, but not other animals, possess this ability has for generations captivated scientists seeking to induce this phenomenon in other vertebrates. Although many recent advances in molecular biology have allowed limb regeneration and tissue repair in the axolotl to be investigated in increasing detail, the molecular toolkit for the study of this process has been limited. Here, we report that the CRISPR-Cas9 RNA-guided nuclease system can efficiently create mutations at targeted sites within the axolotl genome. We identify individual animals treated with RNA-guided nucleases that have mutation frequencies close to 100% at targeted sites. We employ this technique to completely functionally ablate EGFP expression in transgenic animals and recapitulate developmental phenotypes produced by loss of the conserved gene brachyury. Thus, this advance allows a reverse genetic approach in the axolotl and will undoubtedly provide invaluable insight into the mechanisms of salamanders' unique regenerative ability. PMID:24764077

Novel Design of a Soft Lightweight Pneumatic Continuum Robot Arm with Decoupled Variable Stiffness and Positioning.

PubMed

Giannaccini, Maria Elena; Xiang, Chaoqun; Atyabi, Adham; Theodoridis, Theo; Nefti-Meziani, Samia; Davis, Steve

2018-02-01

Soft robot arms possess unique capabilities when it comes to adaptability, flexibility, and dexterity. In addition, soft systems that are pneumatically actuated can claim high power-to-weight ratio. One of the main drawbacks of pneumatically actuated soft arms is that their stiffness cannot be varied independently from their end-effector position in space. The novel robot arm physical design presented in this article successfully decouples its end-effector positioning from its stiffness. An experimental characterization of this ability is coupled with a mathematical analysis. The arm combines the light weight, high payload to weight ratio and robustness of pneumatic actuation with the adaptability and versatility of variable stiffness. Light weight is a vital component of the inherent safety approach to physical human-robot interaction. To characterize the arm, a neural network analysis of the curvature of the arm for different input pressures is performed. The curvature-pressure relationship is also characterized experimentally.

Serotype classification of Streptococcus mutans and its detection outside the oral cavity.

PubMed

Nakano, Kazuhiko; Ooshima, Takashi

2009-09-01

Streptococcus mutans, generally known as a major pathogen of dental caries, is also a possible causative agent of bacteremia and infective endocarditis. S. mutans is classified into serotypes c, e, f and k based on the chemical composition of serotype-specific polysaccharides, with approximately 70-80% of strains found in the oral cavity classified as serotype c, followed by e (approximately 20%), and f and k (less than 5% each). Serotype k was recently designated as a novel serotype and shown to possess unique features, the most prominent being a defect of the glucose side chain in serotype-specific rhamnose-glucose polymers, which is related to a higher incidence of detection in cardiovascular specimens, owing to phagocytosis resistance. Molecular analyses of cardiovascular specimens showed a high detection frequency for S. mutans DNA, among which the detection rate for serotype k was quite high. These findings suggest that serotype k S. mutans possibly has a high level of virulence for systemic diseases.

Nitroxide-Based Macromolecular Contrast Agents with Unprecedented Transverse Relaxivity and Stability for Magnetic Resonance Imaging of Tumors

PubMed Central

2017-01-01

Metal-free magnetic resonance imaging (MRI) agents could overcome the established toxicity associated with metal-based agents in some patient populations and enable new modes of functional MRI in vivo. Herein, we report nitroxide-functionalized brush-arm star polymer organic radical contrast agents (BASP-ORCAs) that overcome the low contrast and poor in vivo stability associated with nitroxide-based MRI contrast agents. As a consequence of their unique nanoarchitectures, BASP-ORCAs possess per-nitroxide transverse relaxivities up to ∼44-fold greater than common nitroxides, exceptional stability in highly reducing environments, and low toxicity. These features combine to provide for accumulation of a sufficient concentration of BASP-ORCA in murine subcutaneous tumors up to 20 h following systemic administration such that MRI contrast on par with metal-based agents is observed. BASP-ORCAs are, to our knowledge, the first nitroxide MRI contrast agents capable of tumor imaging over long time periods using clinical high-field 1H MRI techniques. PMID:28776023

Microwave spectroscopy of biomolecular building blocks.

PubMed

Alonso, José L; López, Juan C

2015-01-01

Microwave spectroscopy, considered as the most definitive gas phase structural probe, is able to distinguish between different conformational structures of a molecule, because they have unique spectroscopic constants and give rise to distinct individual rotational spectra.Previously, application of this technique was limited to molecular specimens possessing appreciable vapor pressures, thus discarding the possibility of studying many other molecules of biological importance, in particular those with high melting points, which had a tendency to undergo thermal reactions, and ultimately degradation, upon heating.Nowadays, the combination of laser ablation with Fourier transform microwave spectroscopy techniques, in supersonic jets, has enabled the gas-phase study of such systems. In this chapter, these techniques, including broadband spectroscopy, as well as results of their application into the study of the conformational panorama and structure of biomolecular building blocks, such as amino acids, nucleic bases, and monosaccharides, are briefly discussed, and with them, the tools for conformational assignation - rotational constants, nuclear quadrupole coupling interaction, and dipole moment.

Strain-relief by single dislocation loops in calcite crystals grown on self-assembled monolayers

DOE PAGES

Ihli, Johannes; Clark, Jesse N.; Côté, Alexander S.; ...

2016-06-15

Most of our knowledge of dislocation-mediated stress relaxation during epitaxial crystal growth comes from the study of inorganic heterostructures. In this study, we use Bragg coherent diffraction imaging to investigate a contrasting system, the epitaxial growth of calcite (CaCO 3) crystals on organic self-assembled monolayers, where these are widely used as a model for biomineralization processes. The calcite crystals are imaged to simultaneously visualize the crystal morphology and internal strain fields. Our data reveal that each crystal possesses a single dislocation loop that occupies a common position in every crystal. The loops exhibit entirely different geometries to misfit dislocations generatedmore » in conventional epitaxial thin films and are suggested to form in response to the stress field, arising from interfacial defects and the nanoscale roughness of the substrate. In conclusion, this work provides unique insight into how self-assembled monolayers control the growth of inorganic crystals and demonstrates important differences as compared with inorganic substrates.« less

Nanoparticle agglomerates of fluticasone propionate in combination with albuterol sulfate as dry powder aerosols

PubMed Central

El-Gendy, Nashwa; Pornputtapitak, Warangkana; Berkland, Cory

2015-01-01

Particle engineering strategies remain at the forefront of aerosol research for localized treatment of lung diseases and represent an alternative for systemic drug therapy. With the hastily growing popularity and complexity of inhalation therapy, there is a rising demand for tailor-made inhalable drug particles capable of affording the most proficient delivery to the lungs and the most advantageous therapeutic outcomes. To address this formulation demand, nanoparticle agglomeration was used to develop aerosols of the asthma therapeutics, fluticasone or albuterol. In addition, a combination aerosol was formed by drying agglomerates of fluticasone nanoparticles in the presence of albuterol in solution. Powders of the single drug nanoparticle agglomerates or of the combined therapeutics possessed desirable aerodynamic properties for inhalation. Powders were efficiently aerosolized (~75% deposition determined by cascade impaction) with high fine particle fraction and rapid dissolution. Nanoparticle agglomeration offers a unique approach to obtain high performance aerosols from combinations of asthma therapeutics. PMID:21964203

Robust self-cleaning and micromanipulation capabilities of gecko spatulae and their bio-mimics

NASA Astrophysics Data System (ADS)

Xu, Quan; Wan, Yiyang; Hu, Travis Shihao; Liu, Tony X.; Tao, Dashuai; Niewiarowski, Peter H.; Tian, Yu; Liu, Yue; Dai, Liming; Yang, Yanqing; Xia, Zhenhai

2015-11-01

Geckos have the extraordinary ability to prevent their sticky feet from fouling while running on dusty walls and ceilings. Understanding gecko adhesion and self-cleaning mechanisms is essential for elucidating animal behaviours and rationally designing gecko-inspired devices. Here we report a unique self-cleaning mechanism possessed by the nano-pads of gecko spatulae. The difference between the velocity-dependent particle-wall adhesion and the velocity-independent spatula-particle dynamic response leads to a robust self-cleaning capability, allowing geckos to efficiently dislodge dirt during their locomotion. Emulating this natural design, we fabricate artificial spatulae and micromanipulators that show similar effects, and that provide a new way to manipulate micro-objects. By simply tuning the pull-off velocity, our gecko-inspired micromanipulators, made of synthetic microfibers with graphene-decorated micro-pads, can easily pick up, transport, and drop-off microparticles for precise assembling. This work should open the door to the development of novel self-cleaning adhesives, smart surfaces, microelectromechanical systems, biomedical devices, and more.

Recent advances in research applications of nanophase hydroxyapatite.

PubMed

Fox, Kate; Tran, Phong A; Tran, Nhiem

2012-07-16

Hydroxyapatite, the main inorganic material in natural bone, has been used widely for orthopaedic applications. Due to size effects and surface phenomena at the nanoscale, nanophase hydroxyapatite possesses unique properties compared to its bulk-phase counterpart. The high surface-to-volume ratio, reactivities, and biomimetic morphologies make nano-hydroxyapatite more favourable in applications such as orthopaedic implant coating or bone substitute filler. Recently, more efforts have been focused on the possibility of combining hydroxyapatite with other drugs and materials for multipurpose applications, such as antimicrobial treatments, osteoporosis treatments and magnetic manipulation. To build more effective nano-hydroxyapatite and composite systems, the particle synthesis processes, chemistry, and toxicity have to be thoroughly investigated. In this Minireview, we report the recent advances in research regarding nano-hydroxyapatite. Synthesis routes and a wide range of applications of hydroxyapatite nanoparticles will be discussed. The Minireview also addresses several challenges concerning the biosafety of the nanoparticles. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Photonic crystal fiber long-period gratings for structural monitoring and chemical sensing

NASA Astrophysics Data System (ADS)

Tang, Jaw-Luen; Wang, Jian-Neng

2008-03-01

We present a simple, low-cost, temperature- and strain-insensitive long-period gratings (LPGs) written in photonic crystal fibers (PCFs) that can be used as sensitive chemical solution sensors or bend sensors for a variety of industrial applications, including civil engineering, aircraft, chemistry, food industry, and biosensing. Three different configurations of PCFs have been used for this study, including a polarization maintaining PCF, a large mode area PCF and an endlessly single mode PCF. These LPGs have been characterized for their sensitivity to temperature, strain, bending, and surrounding refractive index. Transmission spectra of the LPGs were found to exhibit negligible temperature and strain sensitivities, whereas possessing usable sensitivity to refractive index and bending. This type of PCF sensor could in principle be designed for optimum sensitivity to desired measurand(s), while minimizing or removing undesirable cross-sensitivities. The unique sensing features of PCFs are particularly suited for a wide variety of applications in smart structures, embedded materials, telecommunications and sensor systems.

Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites

DOE PAGES

Andersen, Tassie K.; Cook, Seyoung; Wan, Gang; ...

2018-01-18

Here, control over structure and composition of (ABO 3) perovskite oxides offers exciting opportunities since these materials possess unique, tunable properties. Perovskite oxides with cobalt B-site cations are particularly promising, as the range of the cation’s stable oxidation states leads to many possible structural frameworks. Here, we report growth of strontium cobalt oxide thin films by molecular beam epitaxy, and conditions necessary to stabilize different defect concentration phases. In situ X-ray scattering is used to monitor structural evolution during growth, while in situ X-ray absorption near-edge spectroscopy is used to probe oxidation state and measure changes to oxygen vacancy concentrationmore » as a function of film thickness. Experimental results are compared to kinetically-limited thermodynamic predictions, in particular, solute trapping, with semi-quantitative agreement. Agreement between observations of dependence of cobaltite phase on oxidation activity and deposition rate, and predictions indicates that a combined experimental/theoretical approach is key to understanding phase behavior in the strontium cobalt oxide system.« less

Layer-by-layer epitaxial growth of defect-engineered strontium cobaltites

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

Andersen, Tassie K.; Cook, Seyoung; Wan, Gang

Here, control over structure and composition of (ABO 3) perovskite oxides offers exciting opportunities since these materials possess unique, tunable properties. Perovskite oxides with cobalt B-site cations are particularly promising, as the range of the cation’s stable oxidation states leads to many possible structural frameworks. Here, we report growth of strontium cobalt oxide thin films by molecular beam epitaxy, and conditions necessary to stabilize different defect concentration phases. In situ X-ray scattering is used to monitor structural evolution during growth, while in situ X-ray absorption near-edge spectroscopy is used to probe oxidation state and measure changes to oxygen vacancy concentrationmore » as a function of film thickness. Experimental results are compared to kinetically-limited thermodynamic predictions, in particular, solute trapping, with semi-quantitative agreement. Agreement between observations of dependence of cobaltite phase on oxidation activity and deposition rate, and predictions indicates that a combined experimental/theoretical approach is key to understanding phase behavior in the strontium cobalt oxide system.« less

Layer-by-Layer Epitaxial Growth of Defect-Engineered Strontium Cobaltites

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

Andersen, Tassie K.; Cook, Seyoung; Wan, Gang

Control over structure and composition of (ABO(3)) perovskite oxides offers exciting opportunities since these materials possess unique, tunable properties. Perovskite oxides with cobalt B-site cations are particularly promising, as the range of the cations stable oxidation states leads to many possible structural frameworks. Here, we report growth of strontium cobalt oxide thin films by molecular beam epitaxy, and conditions necessary to stabilize different defect concentration phases. In situ X-ray scattering is used to monitor structural evolution during growth, while in situ X-ray absorption near-edge spectroscopy is used to probe oxidation state and measure changes to oxygen vacancy concentration as amore » function of film thickness. Experimental results are compared to kinetically limited thermodynamic predictions, in particular, solute trapping, with semiquantitative agreement. Agreement between observations of dependence of cobaltite phase on oxidation activity and deposition rate, and predictions indicates that a combined experimental/theoretical approach is key to understanding phase behavior in the strontium cobalt oxide system.« less

A turn-on fluorescent probe for simultaneous sensing of cysteine/homocysteine and hydrogen sulfide and its bioimaging applications.

PubMed

Chen, Fengzao; Han, Deman; Gao, Yuan; Liu, Heng; Wang, Shengfu; Zhou, Fangyu; Li, Kaibin; Zhang, Siqi; Shao, Wujun; He, Yanling

2018-09-01

Hydrogen sulfide and biothiol molecules such as Cys, Hcy, and GSH play important roles in biological systems. Exploiting a probe to simultaneously detect and distinguish them is quite important. In this work, a versatile fluorescent probe that can simultaneously detect and discriminate Cys/Hcy and H 2 S is reported. The probe easily prepared by the Knoevenagel condensation of cyanoacetylindole with chlorinated phenyl-propenal possessed three potential sites that could react with biothiols and H 2 S. This probe also exhibited rapidity, high selectivity, and sensitivity for Cys/Hcy and H 2 S with distinct optical signal changes. The probe was able to display obvious fluorescence enhancement at 480 nm for Cys/Hcy and unique absorbance enhancement at 500 nm for H 2 S. We also demonstrated that the probe can be successfully applied to image Cys in MCF-7 cells suing a confocal fluorescence microscope. Copyright © 2018 Elsevier B.V. All rights reserved.

IN VITRO AND IN VIVO ACTIVITY OF A LYMPHOCYTE AND IMMUNE COMPLEX-DEPENDENT CHEMOTACTIC FACTOR FOR EOSINOPHILS

PubMed Central

Cohen, Stanley; Ward, Peter A.

1971-01-01

When cultured in the presence of specific antigen, lymphocytes from delayed-hypersensitive guinea pigs release a number of biologically active substances into the culture medium. Such active supernatants can react with immune complexes in vitro to generate a factor which is chemotactic for eosinophils. The factor involved is unique, since previously described chemotactic factors for other cell types require for their generation either immune complexes or substances released into lymphocyte culture, but not both. In the case of the eosinophil chemotactic factor, the interaction between the substance elaborated by the lymphocytes and the immune complexes appears to be specific in that the immune complexes must contain the same antigen as that used to activate the lymphocyte cultures. Although this factor was generated in an in vitro system, it has been shown to possess in vivo as well as in vitro activity. It is therefore possible that this factor may be of biological significance in situations where eosinophils are participants in inflammatory or immunologic reactions. PMID:5099667

Preliminary crystallographic data of the three homologues of the thiol–disulfide oxidoreductase DsbA in Neisseria meningitidis

PubMed Central

Lafaye, Céline; Iwena, Thomas; Ferrer, Jean-Luc; Kroll, J. Simon; Griat, Mickael; Serre, Laurence

2008-01-01

Bacterial virulence depends on the correct folding of surface-exposed proteins, a process that is catalyzed by the thiol-disulfide oxidoreductase DsbA, which facilitates the synthesis of disulfide bonds in Gram-negative bacteria. Uniquely among bacteria, the Neisseria meningitidis genome possesses three genes encoding active DsbAs: DsbA1, DsbA2 and DsbA3. DsbA1 and DsbA2 have been characterized as lipoproteins involved in natural competence and in host-interactive biology, while the function of DsbA3 remains unknown. In an attempt to shed light on the reason for this multiplicity of dsbA genes, the three enzymes from N. meningitidis have been purified and crystallized in the presence of high concentrations of ammonium sulfate. The best crystals were obtained using DsbA1 and DsbA3; they belong to the orthorhombic and tetragonal systems and diffract to 1.5 and 2.7 Å resolution, respectively. PMID:18259062

Abell 1142 and the Missing Central Galaxy – A Cluster in Transition?

NASA Astrophysics Data System (ADS)

Jones, Alexander; Su, Yuanyuan; Buote, David; Forman, William; van Weeren, Reinout; Jones, Christine; Gastaldello, Fabio; Kraft, Ralph; Randall, Scott

2018-01-01

Two types of galaxy clusters exist: cool core (CC) clusters which exhibit centrally-peaked metallicity and X-ray emission and non-cool core (NCC) clusters, possessing comparably homogeneous metallicity and X-ray emission distributions. However, the origin of this dichotomy is still unknown. The current prevailing theories state that either there is a primordial entropy limit, above which a CC is unable to form, or that clusters can change type through major mergers and radiative cooling. Abell 1142 is a galaxy cluster that can provide a unique probe of the root of this cluster-type division. It is formed of two merging sub-clusters, each with its own brightest cluster galaxies (BCG). Its enriched X-ray centroid (possible CC remnant) lies between these two BCGs. We present the thermal and chemical distributions of this system using deep (180ks) XMM-Newton observations to shed light on the role of mergers in the evolution of galaxy clusters.

Pressure induced metallization with absence of structural transition in layered molybdenum diselenide

PubMed Central

Zhao, Zhao; Zhang, Haijun; Yuan, Hongtao; Wang, Shibing; Lin, Yu; Zeng, Qiaoshi; Xu, Gang; Liu, Zhenxian; Solanki, G. K.; Patel, K. D.; Cui, Yi; Hwang, Harold Y.; Mao, Wendy L.

2015-01-01

Layered transition-metal dichalcogenides have emerged as exciting material systems with atomically thin geometries and unique electronic properties. Pressure is a powerful tool for continuously tuning their crystal and electronic structures away from the pristine states. Here, we systematically investigated the pressurized behavior of MoSe2 up to ∼60 GPa using multiple experimental techniques and ab-initio calculations. MoSe2 evolves from an anisotropic two-dimensional layered network to a three-dimensional structure without a structural transition, which is a complete contrast to MoS2. The role of the chalcogenide anions in stabilizing different layered patterns is underscored by our layer sliding calculations. MoSe2 possesses highly tunable transport properties under pressure, determined by the gradual narrowing of its band-gap followed by metallization. The continuous tuning of its electronic structure and band-gap in the range of visible light to infrared suggest possible energy-variable optoelectronics applications in pressurized transition-metal dichalcogenides. PMID:26088416

Comparison of natural and nonnative two-species communities of Anolis lizards.

PubMed

Poe, Steven

2014-07-01

Human-mediated colonizations present an informative model system for understanding assembly of organismal communities. However, it is unclear whether communities including naturalized species are accurate analogs of natural communities or unique combinations not present in nature. I compared morphology and phylogenetic structure of natural and naturalized two-species communities of Anolis lizards. Natural communities are phylogenetically clustered, whereas naturalized communities show no significant phylogenetic structure. This result likely reflects differences in colonization pools for these communities-that is, invasion from anywhere for naturalized communities but from proximal and thus phylogenetically close lineages in natural communities. Both natural and naturalized communities each include pairs of species that are significantly similar to each other in morphology, and both sets of communities are composed of species that possess traits of good colonizers. These similarities suggest that the formation of natural and naturalized communities may be at least partially governed by similar processes. Human-mediated invasions may be credibly viewed as modern incarnations of natural colonizations in this case.

Distinct antimicrobial peptide expression determines host species-specific bacterial associations

PubMed Central

Franzenburg, Sören; Walter, Jonas; Künzel, Sven; Wang, Jun; Baines, John F.; Bosch, Thomas C. G.; Fraune, Sebastian

2013-01-01

Animals are colonized by coevolved bacterial communities, which contribute to the host’s health. This commensal microbiota is often highly specific to its host-species, inferring strong selective pressures on the associated microbes. Several factors, including diet, mucus composition, and the immune system have been proposed as putative determinants of host-associated bacterial communities. Here we report that species-specific antimicrobial peptides account for different bacterial communities associated with closely related species of the cnidarian Hydra. Gene family extensions for potent antimicrobial peptides, the arminins, were detected in four Hydra species, with each species possessing a unique composition and expression profile of arminins. For functional analysis, we inoculated arminin-deficient and control polyps with bacterial consortia characteristic for different Hydra species and compared their selective preferences by 454 pyrosequencing of the bacterial microbiota. In contrast to control polyps, arminin-deficient polyps displayed decreased potential to select for bacterial communities resembling their native microbiota. This finding indicates that species-specific antimicrobial peptides shape species-specific bacterial associations. PMID:24003149

Numerical study of MHD nanofluid flow and heat transfer past a bidirectional exponentially stretching sheet

NASA Astrophysics Data System (ADS)

Ahmad, Rida; Mustafa, M.; Hayat, T.; Alsaedi, A.

2016-06-01

Recent advancements in nanotechnology have led to the discovery of new generation coolants known as nanofluids. Nanofluids possess novel and unique characteristics which are fruitful in numerous cooling applications. Current work is undertaken to address the heat transfer in MHD three-dimensional flow of magnetic nanofluid (ferrofluid) over a bidirectional exponentially stretching sheet. The base fluid is considered as water which consists of magnetite-Fe3O4 nanoparticles. Exponentially varying surface temperature distribution is accounted. Problem formulation is presented through the Maxwell models for effective electrical conductivity and effective thermal conductivity of nanofluid. Similarity transformations give rise to a coupled non-linear differential system which is solved numerically. Appreciable growth in the convective heat transfer coefficient is observed when nanoparticle volume fraction is augmented. Temperature exponent parameter serves to enhance the heat transfer from the surface. Moreover the skin friction coefficient is directly proportional to both magnetic field strength and nanoparticle volume fraction.

Detection of Myoglobin with an Open-Cavity-Based Label-Free Photonic Crystal Biosensor.

PubMed

Zhang, Bailin; Tamez-Vela, Juan Manuel; Solis, Steven; Bustamante, Gilbert; Peterson, Ralph; Rahman, Shafiqur; Morales, Andres; Tang, Liang; Ye, Jing Yong

2013-01-01

The label-free detection of one of the cardiac biomarkers, myoglobin, using a photonic-crystal-based biosensor in a total-internal-reflection configuration (PC-TIR) is presented in this paper. The PC-TIR sensor possesses a unique open optical microcavity that allows for several key advantages in biomolecular assays. In contrast to a conventional closed microcavity, the open configuration allows easy functionalization of the sensing surface for rapid biomolecular binding assays. Moreover, the properties of PC structures make it easy to be designed and engineered for operating at any optical wavelength. Through fine design of the photonic crystal structure, biochemical modification of the sensor surface, and integration with a microfluidic system, we have demonstrated that the detection sensitivity of the sensor for myoglobin has reached the clinically significant concentration range, enabling potential usage of this biosensor for diagnosis of acute myocardial infarction. The real-time response of the sensor to the myoglobin binding may potentially provide point-of-care monitoring of patients and treatment effects.

Antimicrobial properties of a nanostructured eggshell from a compost-nesting bird.

PubMed

D'Alba, Liliana; Jones, Darryl N; Badawy, Hope T; Eliason, Chad M; Shawkey, Matthew D

2014-04-01

Infection is an important source of mortality for avian embryos but parental behaviors and eggs themselves can provide a network of antimicrobial defenses. Mound builders (Aves: Megapodiidae) are unique among birds in that they produce heat for developing embryos not by sitting on eggs but by burying them in carefully tended mounds of soil and microbially decomposing vegetation. The low infection rate of eggs of one species in particular, the Australian brush-turkey (Alectura lathami), suggests that they possess strong defensive mechanisms. To identify some of these mechanisms, we first quantified antimicrobial albumen proteins and characterized eggshell structure, finding that albumen was not unusually antimicrobial, but that eggshell cuticle was composed of nanometer-sized calcite spheres. Experimental tests revealed that these modified eggshells were significantly more hydrophobic and better at preventing bacterial attachment and penetration into the egg contents than chicken eggs. Our results suggest that these mechanisms may contribute to the antimicrobial defense system of these eggs, and may provide inspiration for new biomimetic anti-fouling surfaces.

Size-tunable silicon/iron oxide hybrid nanoparticles with fluorescence, superparamagnetism, and biocompatibility.

PubMed

Sato, Keisuke; Yokosuka, Shinobu; Takigami, Yasunori; Hirakuri, Kenji; Fujioka, Kouki; Manome, Yoshinobu; Sukegawa, Hiroaki; Iwai, Hideo; Fukata, Naoki

2011-11-23

Magnetic/fluorescent composite materials have become one of the most important tools in the imaging modality in vivo using magnetic resonance imaging (MRI) monitoring and fluorescence optical imaging. We report herein on a simplified procedure to synthesize hybrid nanoparticles (HNPs) that combine silicon and magnetic iron oxides consisting of magnetite (Fe(3)O(4)) and maghemite (γ-Fe(2)O(3)). Intriguingly, our unique synthetic approach can control magnetic and optical behaviors by reducing the particle size, demonstrating that the HNPs with the mean diameter of 3.0 nm exhibit superparamagnetic behavior and green fluorescence in an aqueous solution, ambient air, and a cellular environment, whereas the HNPs with the mean diameter more than 5.0 nm indicate ferromagnetic behavior without fluorescence. Additionally, both HNPs with different diameters possess excellent magnetic responsivity for external applied magnetic field and good biocompatibility due to the low cytotoxicity. Our biocompatible HNPs with the superparamagnetism can provide an attractive approach for diagnostic imaging system in vivo.

Pressure induced metallization with absence of structural transition in layered molybdenum diselenide

DOE PAGES

Zhao, Zhao; Zhang, Haijun; Yuan, Hongtao; ...

2015-06-19

Layered transition-metal dichalcogenides have emerged as exciting material systems with atomically thin geometries and unique electronic properties. Pressure is a powerful tool for continuously tuning their crystal and electronic structures away from the pristine states. Here, we systematically investigated the pressurized behavior of MoSe 2 up to ~60 GPa using multiple experimental techniques and ab-initio calculations. MoSe 2 evolves from an anisotropic two-dimensional layered network to a three-dimensional structure without a structural transition, which is a complete contrast to MoS 2. The role of the chalcogenide anions in stabilizing different layered patterns is underscored by our layer sliding calculations. MoSemore » 2 possesses highly tunable transport properties under pressure, determined by the gradual narrowing of its band-gap followed by metallization. The continuous tuning of its electronic structure and band-gap in the range of visible light to infrared suggest possible energy-variable optoelectronics applications in pressurized transition-metal dichalcogenides.« less

Novel Design of a Soft Lightweight Pneumatic Continuum Robot Arm with Decoupled Variable Stiffness and Positioning

PubMed Central

Xiang, Chaoqun; Atyabi, Adham; Theodoridis, Theo; Nefti-Meziani, Samia; Davis, Steve

2018-01-01

Abstract Soft robot arms possess unique capabilities when it comes to adaptability, flexibility, and dexterity. In addition, soft systems that are pneumatically actuated can claim high power-to-weight ratio. One of the main drawbacks of pneumatically actuated soft arms is that their stiffness cannot be varied independently from their end-effector position in space. The novel robot arm physical design presented in this article successfully decouples its end-effector positioning from its stiffness. An experimental characterization of this ability is coupled with a mathematical analysis. The arm combines the light weight, high payload to weight ratio and robustness of pneumatic actuation with the adaptability and versatility of variable stiffness. Light weight is a vital component of the inherent safety approach to physical human-robot interaction. To characterize the arm, a neural network analysis of the curvature of the arm for different input pressures is performed. The curvature-pressure relationship is also characterized experimentally. PMID:29412080

Strain-relief by single dislocation loops in calcite crystals grown on self-assembled monolayers

PubMed Central

Ihli, Johannes; Clark, Jesse N.; Côté, Alexander S.; Kim, Yi-Yeoun; Schenk, Anna S.; Kulak, Alexander N.; Comyn, Timothy P.; Chammas, Oliver; Harder, Ross J.; Duffy, Dorothy M.; Robinson, Ian K.; Meldrum, Fiona C.

2016-01-01

Most of our knowledge of dislocation-mediated stress relaxation during epitaxial crystal growth comes from the study of inorganic heterostructures. Here we use Bragg coherent diffraction imaging to investigate a contrasting system, the epitaxial growth of calcite (CaCO3) crystals on organic self-assembled monolayers, where these are widely used as a model for biomineralization processes. The calcite crystals are imaged to simultaneously visualize the crystal morphology and internal strain fields. Our data reveal that each crystal possesses a single dislocation loop that occupies a common position in every crystal. The loops exhibit entirely different geometries to misfit dislocations generated in conventional epitaxial thin films and are suggested to form in response to the stress field, arising from interfacial defects and the nanoscale roughness of the substrate. This work provides unique insight into how self-assembled monolayers control the growth of inorganic crystals and demonstrates important differences as compared with inorganic substrates. PMID:27302863

Cranial arterial patterns of the alpaca (Camelidae: Vicugna pacos).

PubMed

O'Brien, Haley D

2017-03-01

Artiodactyl cranial arterial patterns deviate significantly from the standard mammalian pattern, most notably in the possession of a structure called the carotid rete (CR)-a subdural arterial meshwork that is housed within the cavernous venous sinus, replacing the internal carotid artery (ICA). This relationship between the CR and the cavernous sinus facilitates a suite of unique physiologies, including selective brain cooling. The CR has been studied in a number of artiodactyls; however, to my knowledge, only a single study to date documents a subset of the cranial arteries of New World camelids (llamas, alpacas, vicugñas and guanacoes). This study is the first complete description of the cranial arteries of a New World camelid species, the alpaca ( Vicugna pacos ), and the first description of near-parturition cranial arterial morphology within New World camelids. This study finds that the carotid arterial system is conserved between developmental stages in the alpaca, and differs significantly from the pattern emphasized in other long-necked ruminant artiodactyls in that a patent, homologous ICA persists through the animal's life.

Coded aperture ptychography: uniqueness and reconstruction

NASA Astrophysics Data System (ADS)

Chen, Pengwen; Fannjiang, Albert

2018-02-01

Uniqueness of solution is proved for any ptychographic scheme with a random mask under a minimum overlap condition and local geometric convergence analysis is given for the alternating projection (AP) and Douglas-Rachford (DR) algorithms. DR is shown to possess a unique fixed point in the object domain and for AP a simple criterion for distinguishing the true solution among possibly many fixed points is given. A minimalist scheme, where the adjacent masks overlap 50% of the area and each pixel of the object is illuminated by exactly four illuminations, is conveniently parametrized by the number q of shifted masks in each direction. The lower bound 1  -  C/q 2 is proved for the geometric convergence rate of the minimalist scheme, predicting a poor performance with large q which is confirmed by numerical experiments. The twin-image ambiguity is shown to arise for certain Fresnel masks and degrade the performance of reconstruction. Extensive numerical experiments are performed to explore the general features of a well-performing mask, the optimal value of q and the robustness with respect to measurement noise.

Diversity and Evolution of Bacterial Twin Arginine Translocase Protein, TatC, Reveals a Protein Secretion System That Is Evolving to Fit Its Environmental Niche

PubMed Central

Simone, Domenico; Bay, Denice C.; Leach, Thorin; Turner, Raymond J.

2013-01-01

Background The twin-arginine translocation (Tat) protein export system enables the transport of fully folded proteins across a membrane. This system is composed of two integral membrane proteins belonging to TatA and TatC protein families and in some systems a third component, TatB, a homolog of TatA. TatC participates in substrate protein recognition through its interaction with a twin arginine leader peptide sequence. Methodology/Principal Findings The aim of this study was to explore TatC diversity, evolution and sequence conservation in bacteria to identify how TatC is evolving and diversifying in various bacterial phyla. Surveying bacterial genomes revealed that 77% of all species possess one or more tatC loci and half of these classes possessed only tatC and tatA genes. Phylogenetic analysis of diverse TatC homologues showed that they were primarily inherited but identified a small subset of taxonomically unrelated bacteria that exhibited evidence supporting lateral gene transfer within an ecological niche. Examination of bacilli tatCd/tatCy isoform operons identified a number of known and potentially new Tat substrate genes based on their frequent association to tatC loci. Evolutionary analysis of these Bacilli isoforms determined that TatCy was the progenitor of TatCd. A bacterial TatC consensus sequence was determined and highlighted conserved and variable regions within a three dimensional model of the Escherichia coli TatC protein. Comparative analysis between the TatC consensus sequence and Bacilli TatCd/y isoform consensus sequences revealed unique sites that may contribute to isoform substrate specificity or make TatA specific contacts. Synonymous to non-synonymous nucleotide substitution analyses of bacterial tatC homologues determined that tatC sequence variation differs dramatically between various classes and suggests TatC specialization in these species. Conclusions/Significance TatC proteins appear to be diversifying within particular bacterial classes and its specialization may be driven by the substrates it transports and the environment of its host. PMID:24236045

Comparative Genomics of the Ectomycorrhizal Sister Species Rhizopogon vinicolor and Rhizopogon vesiculosus (Basidiomycota: Boletales) Reveals a Divergence of the Mating Type B Locus

PubMed Central

Mujic, Alija Bajro; Kuo, Alan; Tritt, Andrew; Lipzen, Anna; Chen, Cindy; Johnson, Jenifer; Sharma, Aditi; Barry, Kerrie; Grigoriev, Igor V.; Spatafora, Joseph W.

2017-01-01

Divergence of breeding system plays an important role in fungal speciation. Ectomycorrhizal fungi, however, pose a challenge for the study of reproductive biology because most cannot be mated under laboratory conditions. To overcome this barrier, we sequenced the draft genomes of the ectomycorrhizal sister species Rhizopogon vinicolor Smith and Zeller and R. vesiculosus Smith and Zeller (Basidiomycota, Boletales)—the first genomes available for Basidiomycota truffles—and characterized gene content and organization surrounding their mating type loci. Both species possess a pair of homeodomain transcription factor homologs at the mating type A-locus as well as pheromone receptor and pheromone precursor homologs at the mating type B-locus. Comparison of Rhizopogon genomes with genomes from Boletales, Agaricales, and Polyporales revealed synteny of the A-locus region within Boletales, but several genomic rearrangements across orders. Our findings suggest correlation between gene content at the B-locus region and breeding system in Boletales with tetrapolar species possessing more diverse gene content than bipolar species. Rhizopogon vinicolor possesses a greater number of B-locus pheromone receptor and precursor genes than R. vesiculosus, as well as a pair of isoprenyl cysteine methyltransferase genes flanking the B-locus compared to a single copy in R. vesiculosus. Examination of dikaryotic single nucleotide polymorphisms within genomes revealed greater heterozygosity in R. vinicolor, consistent with increased rates of outcrossing. Both species possess the components of a heterothallic breeding system with R. vinicolor possessing a B-locus region structure consistent with tetrapolar Boletales and R. vesiculosus possessing a B-locus region structure intermediate between bipolar and tetrapolar Boletales. PMID:28450370

Hypocholesterolemic and bioactive potential of exopolysaccharide from a probiotic Enterococcus faecium K1 isolated from kalarei.

PubMed

Bhat, Bilqeesa; Bajaj, Bijender Kumar

2018-04-01

Bioprospecting of novel probiotic strains especially from unexplored eco-niches has been a continuous practice. Enterococcus faecium K1, an isolate from indigenously fermented milk product kalarei possesses numerous desirable functional attributes. In current study, E. faecium K1 has been used for EPS production, and it yielded 355 ± 0.019 mg/L EPS. EPS demonstrates remarkable hypocholesterolemic, antioxidant, antibiofilm, and emulsification characteristics. EPS is constituted of mannose, glucose and galactose. SEM analysis reveals flake like compact structure of EPS while TEM and X-ray diffractogram confirms the amorphous structure of EPS. FTIR substantiates the functional groups/bonds typical of polysaccharides. Thermal analysis indicates adequate stability of EPS at 237 °C with average weight loss of 22%. E. faecium K1 EPS possesses unique functional bioactivities and physicochemical characteristics, and may potentially be explored for applications in food/pharmaceutical industries. Copyright © 2018 Elsevier Ltd. All rights reserved.

Two peculiar new species of Heteranthera Ruiz & Pavón (Pontederiaceae) from Brazil, with notes on inflorescence architecture in the family

PubMed Central

Pellegrini, Marco O. O.; Horn, Charles N.

2017-01-01

Abstract Two new and peculiar species of Heteranthera are herein described. Heteranthera catharinensis is unique in the genus due to its glomerulate, many-flowered inflorescences, in which the flowers are restricted to the base and apex of the cincinni. It also possesses the biggest flowers in the H. reniformis Ruiz & Pavón species complex, with glabrous perianth lobes, medial filament, and style. On the other hand, Heteranthera pumila is described as the smallest known species of Pontederiaceae, with its dwarf stature, petiolate leaves with especially diminute blades, inflorescences 1–2–(3)-flowered, peduncle densely covered with glandular hairs, basal bract with glandular hairs at base, and smooth seeds, rarely possessing 7–9 inconspicuous longitudinal wings. We present detailed descriptions, illustrations, comments, a distribution map, conservation assessments for the new species, and an identification key to the Brazilian species of Heteranthera s.l. Finally, we discuss inflorescence morphology and terminology in Pontederiaceae, characterizing it as thyrsoid. PMID:28794681

A RuBisCO-mediated carbon metabolic pathway in methanogenic archaea

PubMed Central

Kono, Takunari; Mehrotra, Sandhya; Endo, Chikako; Kizu, Natsuko; Matusda, Mami; Kimura, Hiroyuki; Mizohata, Eiichi; Inoue, Tsuyoshi; Hasunuma, Tomohisa; Yokota, Akiho; Matsumura, Hiroyoshi; Ashida, Hiroki

2017-01-01

Two enzymes are considered to be unique to the photosynthetic Calvin–Benson cycle: ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), responsible for CO2 fixation, and phosphoribulokinase (PRK). Some archaea possess bona fide RuBisCOs, despite not being photosynthetic organisms, but are thought to lack PRK. Here we demonstrate the existence in methanogenic archaea of a carbon metabolic pathway involving RuBisCO and PRK, which we term ‘reductive hexulose-phosphate' (RHP) pathway. These archaea possess both RuBisCO and a catalytically active PRK whose crystal structure resembles that of photosynthetic bacterial PRK. Capillary electrophoresis-mass spectrometric analysis of metabolites reveals that the RHP pathway, which differs from the Calvin–Benson cycle only in a few steps, is active in vivo. Our work highlights evolutionary and functional links between RuBisCO-mediated carbon metabolic pathways in methanogenic archaea and photosynthetic organisms. Whether the RHP pathway allows for autotrophy (that is, growth exclusively with CO2 as carbon source) remains unknown. PMID:28082747

Egocentric pattern projection: how implicit personality theories recapitulate the geography of the self.

PubMed

Critcher, Clayton R; Dunning, David

2009-07-01

Five studies demonstrated egocentric pattern projection, in that the implicit personality theories (IPTs) that participants held about other people tended to recapitulate the terrain of their own personality. To the extent that participants believed they possessed 2 traits to a similar degree within themselves, they tended, through their judgments of others and estimates of population parameters, to claim that the 2 traits were positively correlated in other people; and if they believed they possessed 2 traits to a dissimilar degree within themselves, they tended to claim that the 2 traits were negatively correlated in other people. Further evidence showed that information about the self plays a causal role in the construction of implicit theories, making a unique contribution to the shape of IPTs over and above that of information about another person. The relevance of these data for recent controversies over egocentric social judgment is discussed. (PsycINFO Database Record (c) 2009 APA, all rights reserved).

Structural modeling of glucanase-substrate complexes suggests a conserved tyrosine is involved in carbohydrate recognition in plant 1,3-1,4-β- d-glucanases

NASA Astrophysics Data System (ADS)

Tsai, Li-Chu; Chen, Yi-Ning; Shyur, Lie-Fen

2008-12-01

Glycosyl hydrolase family 16 (GHF16) truncated Fibrobacter succinogenes (TFs) and GHF17 barley 1,3-1,4-β- d-glucanases (β-glucanases) possess different structural folds, β-jellyroll and (β/α)8, although they both catalyze the specific hydrolysis of β-1,4 glycosidic bonds adjacent to β-1,3 linkages in mixed β-1,3 and β-1,4 β- d-glucans or lichenan. Differences in the active site region residues of TFs β-glucanase and barley β-glucanase create binding site topographies that require different substrate conformations. In contrast to barley β-glucanase, TFs β-glucanase possesses a unique and compact active site. The structural analysis results suggest that the tyrosine residue, which is conserved in all known 1,3-1,4-β- d-glucanases, is involved in the recognition of mixed β-1,3 and β-1,4 linked polysaccharide.

Charged rotating black holes in Einstein-Maxwell-Chern-Simons theory with a negative cosmological constant

NASA Astrophysics Data System (ADS)

Blázquez-Salcedo, Jose Luis; Kunz, Jutta; Navarro-Lérida, Francisco; Radu, Eugen

2017-03-01

We consider rotating black hole solutions in five-dimensional Einstein-Maxwell-Chern-Simons theory with a negative cosmological constant and a generic value of the Chern-Simons coupling constant λ . Using both analytical and numerical techniques, we focus on cohomogeneity-1 configurations, with two equal-magnitude angular momenta, which approach at infinity a globally anti-de Sitter background. We find that the generic solutions share a number of basic properties with the known Cvetič, Lü, and Pope black holes which have λ =1 . New features occur as well; for example, when the Chern-Simons coupling constant exceeds a critical value, the solutions are no longer uniquely determined by their global charges. Moreover, the black holes possess radial excitations which can be labelled by the node number of the magnetic gauge potential function. Solutions with small values of λ possess other distinct features. For instance, the extremal black holes there form two disconnected branches, while not all near-horizon solutions are associated with global solutions.

Analysis of the Measurement and Modeling of a Digital Inverter Based on a Ferroelectric Transistor

NASA Technical Reports Server (NTRS)

MacLeod, Todd C.; Phillips, Thomas A.; Sayyah, Rana; Ho, Fat D.

2009-01-01

The use of ferroelectric materials for digital memory devices is widely researched and implemented, but ferroelectric devices also possess unique characteristics that make them have interesting and useful properties in digital circuits. Because ferroelectric transistors possess the properties of hysteresis and nonlinearity, a digital inverter containing a FeFET has very different characteristics than one with a traditional FET. This paper characterizes the properties of the measurement and modeling of a FeFET based digital inverter. The circuit was set up using discrete FeFETs. The purpose of this circuit was not to produce a practical integrated circuit that could be inserted directly into existing digital circuits, but to explore the properties and characteristics of such a device and to look at possible future uses. Input and output characteristics are presented, as well as timing measurements. Comparisons are made between the ferroelectric device and the properties of a standard digital inverter. Potential benefits and possible uses of such a device are presented.

Classification review of dental adhesive systems: from the IV generation to the universal type

PubMed Central

Sofan, Eshrak; Sofan, Afrah; Palaia, Gaspare; Tenore, Gianluca; Romeo, Umberto; Migliau, Guido

2017-01-01

Summary Adhesive dentistry has undergone great progress in the last decades. In light of minimal-invasive dentistry, this new approach promotes a more conservative cavity design, which relies on the effectiveness of current enamel-dentine adhesives. Adhesive dentistry began in 1955 by Buonocore on the benefits of acid etching. With changing technologies, dental adhesives have evolved from no-etch to total-etch (4th and 5th generation) to self-etch (6th, 7th and 8th generation) systems. Currently, bonding to dental substrates is based on three different strategies: 1) etch-and-rinse, 2) self-etch and 3) resin-modified glass-ionomer approach as possessing the unique properties of self-adherence to the tooth tissue. More recently, a new family of dentin adhesives has been introduced (universal or multi-mode adhesives), which may be used either as etch-and-rinse or as self-etch adhesives. The purpose of this article is to review the literature on the current knowledge for each adhesive system according to their classification that have been advocated by many authorities in most operative/restorative procedures. As noted by several valuable studies that have contributed to understanding of bonding to various substrates helps clinicians to choose the appropriate dentin bonding agents for optimal clinical outcomes. PMID:28736601

Aromatic, Alphatic, Enigmatic: The Chemistry of Titan

NASA Astrophysics Data System (ADS)

Horst, Sarah

2017-10-01

The extraordinary complexity of Titan’s atmospheric chemistry far surpasses that of any other solar system atmosphere. With its thick N2 atmosphere and stable bodies of liquid on its surface, Titan also possesses many physical processes that are similar to those that occur on Earth. The connection between Titan’s surface and atmosphere is unique in our solar system; atmospheric chemistry produces materials that are deposited on the surface and subsequently altered by surface-atmosphere interactions such as aeolian and fluvial processes resulting in the formation of extensive dune fields and expansive lakes and seas. Titan’s atmosphere is favorable for organic haze formation, which combined with the presence of some oxygen-bearing molecules indicates that Titan’s atmosphere may produce molecules of prebiotic interest. The combination of organics and liquid, in the form of water in a subsurface ocean and methane/ethane in the surface lakes and seas, means that Titan may be the ideal place in the solar system to test ideas about habitability, prebiotic chemistry, and the ubiquity and diversity of life in the universe. I will review our current understanding of chemistry on Titan forged from the powerful combination of Earth-based observations, remote sensing and in situ spacecraft measurements, laboratory experiments, and models. I will conclude with some of the questions that remain after Cassini-Huygens.

A distributed computational search strategy for the identification of diagnostics targets: application to finding aptamer targets for methicillin-resistant staphylococci.

PubMed

Flanagan, Keith; Cockell, Simon; Harwood, Colin; Hallinan, Jennifer; Nakjang, Sirintra; Lawry, Beth; Wipat, Anil

2014-06-30

The rapid and cost-effective identification of bacterial species is crucial, especially for clinical diagnosis and treatment. Peptide aptamers have been shown to be valuable for use as a component of novel, direct detection methods. These small peptides have a number of advantages over antibodies, including greater specificity and longer shelf life. These properties facilitate their use as the detector components of biosensor devices. However, the identification of suitable aptamer targets for particular groups of organisms is challenging. We present a semi-automated processing pipeline for the identification of candidate aptamer targets from whole bacterial genome sequences. The pipeline can be configured to search for protein sequence fragments that uniquely identify a set of strains of interest. The system is also capable of identifying additional organisms that may be of interest due to their possession of protein fragments in common with the initial set. Through the use of Cloud computing technology and distributed databases, our system is capable of scaling with the rapidly growing genome repositories, and consequently of keeping the resulting data sets up-to-date. The system described is also more generically applicable to the discovery of specific targets for other diagnostic approaches such as DNA probes, PCR primers and antibodies.

Dendrimers as Carriers for siRNA Delivery and Gene Silencing: A Review

PubMed Central

Huang, Weizhe; He, Ziying

2013-01-01

RNA interference (RNAi) was first literaturally reported in 1998 and has become rapidly a promising tool for therapeutic applications in gene therapy. In a typical RNAi process, small interfering RNAs (siRNA) are used to specifically downregulate the expression of the targeted gene, known as the term “gene silencing.” One key point for successful gene silencing is to employ a safe and efficient siRNA delivery system. In this context, dendrimers are emerging as potential nonviral vectors to deliver siRNA for RNAi purpose. Dendrimers have attracted intense interest since their emanating research in the 1980s and are extensively studied as efficient DNA delivery vectors in gene transfer applications, due to their unique features based on the well-defined and multivalent structures. Knowing that DNA and RNA possess a similar structure in terms of nucleic acid framework and the electronegative nature, one can also use the excellent DNA delivery properties of dendrimers to develop effective siRNA delivery systems. In this review, the development of dendrimer-based siRNA delivery vectors is summarized, focusing on the vector features (siRNA delivery efficiency, cytotoxicity, etc.) of different types of dendrimers and the related investigations on structure-activity relationship to promote safe and efficient siRNA delivery system. PMID:24288498

A distributed computational search strategy for the identification of diagnostics targets: Application to finding aptamer targets for methicillin-resistant staphylococci.

PubMed

Flanagan, Keith; Cockell, Simon; Harwood, Colin; Hallinan, Jennifer; Nakjang, Sirintra; Lawry, Beth; Wipat, Anil

2014-06-01

The rapid and cost-effective identification of bacterial species is crucial, especially for clinical diagnosis and treatment. Peptide aptamers have been shown to be valuable for use as a component of novel, direct detection methods. These small peptides have a number of advantages over antibodies, including greater specificity and longer shelf life. These properties facilitate their use as the detector components of biosensor devices. However, the identification of suitable aptamer targets for particular groups of organisms is challenging. We present a semi-automated processing pipeline for the identification of candidate aptamer targets from whole bacterial genome sequences. The pipeline can be configured to search for protein sequence fragments that uniquely identify a set of strains of interest. The system is also capable of identifying additional organisms that may be of interest due to their possession of protein fragments in common with the initial set. Through the use of Cloud computing technology and distributed databases, our system is capable of scaling with the rapidly growing genome repositories, and consequently of keeping the resulting data sets up-to-date. The system described is also more generically applicable to the discovery of specific targets for other diagnostic approaches such as DNA probes, PCR primers and antibodies.

Manipulation of intestinal epithelial cell function by the cell contact-dependent type III secretion systems of Vibrio parahaemolyticus

PubMed Central

O'Boyle, Nicky; Boyd, Aoife

2013-01-01

Vibrio parahaemolyticus elicits gastroenteritis by deploying Type III Secretion Systems (TTSS) to deliver effector proteins into epithelial cells of the human intestinal tract. The bacteria must adhere to the human cells to allow colonization and operation of the TTSS translocation apparatus bridging the bacterium and the host cell. This article first reviews recent advances in identifying the molecules responsible for intercellular adherence. V. parahaemolyticus possesses two TTSS, each of which delivers an exclusive set of effectors and mediates unique effects on the host cell. TTSS effectors primarily target and alter the activation status of host cell signaling proteins, thereby bringing about changes in the regulation of cellular behavior. TTSS1 is responsible for the cytotoxicity of V. parahaemolyticus, while TTSS2 is necessary for the enterotoxicity of the pathogen. Recent publications have elucidated the function of several TTSS effectors and their importance in the virulence of the bacterium. This review will explore the ability of the TTSS to manipulate activities of human intestinal cells and how this modification of cell function favors bacterial colonization and persistence of V. parahaemolyticus in the host. PMID:24455490

Obsessive-compulsive skin disorders: a novel classification based on degree of insight.

PubMed

Zhu, Tian Hao; Nakamura, Mio; Farahnik, Benjamin; Abrouk, Michael; Reichenberg, Jason; Bhutani, Tina; Koo, John

2017-06-01

Individuals with obsessive-compulsive features frequently visit dermatologists for complaints of the skin, hair or nails, and often progress towards a chronic relapsing course due to the challenge associated with accurate diagnosis and management of their psychiatric symptoms. The current DSM-5 formally recognizes body dysmorphic disorder, trichotillomania, neurotic excoriation and body focused repetitive behavior disorder as psychodermatological disorders belonging to the category of Obsessive-Compulsive and Related Disorders. However there is evidence that other relevant skin diseases such as delusions of parasitosis, dermatitis artefacta, contamination dermatitis, AIDS phobia, trichotemnomania and even lichen simplex chronicus possess prominent obsessive-compulsive characteristics that do not necessarily fit the full diagnostic criteria of the DSM-5. Therefore, to increase dermatologists' awareness of this unique group of skin disorders with OCD features, we propose a novel classification system called Obsessive-Compulsive Insight Continuum. Under this new classification system, obsessive-compulsive skin manifestations are categorized along a continuum based on degree of insight, from minimal insight with delusional obsessions to good insight with minimal obsessions. Understanding the level of insight is thus an important first step for clinicians who routinely interact with these patients.

Burrowing hard corals occurring on the sea floor since 80 million years ago.

PubMed

Sentoku, Asuka; Tokuda, Yuki; Ezaki, Yoichi

2016-04-14

We describe a previously unknown niche for hard corals in the small, bowl-shaped, solitary scleractinian, Deltocyathoides orientalis (Family Turbinoliidae), on soft-bottom substrates. Observational experiments were used to clarify how the sea floor niche is exploited by turbinoliids. Deltocyathoides orientalis is adapted to an infaunal mode of life and exhibits behaviours associated with automobility that include burrowing into sediments, vertical movement through sediments to escape burial, and recovery of an upright position after being overturned. These behaviours were achieved through repeated expansion and contraction of their peripheral soft tissues, which constitute a unique muscle-membrane system. Histological analysis showed that these muscle arrangements were associated with deeply incised inter-costal spaces characteristic of turbinoliid corals. The oldest known turbinoliid, Bothrophoria ornata, which occurred in the Cretaceous (Campanian), also possessed a small, conical skeleton with highly developed costae. An infaunal mode of life became available to turbinoliids due to the acquisition of automobility through the muscle-membrane system at least 80 million years ago. The newly discovered active burrowing strategies described herein provide new insights into the use of an unattached mode of life by corals inhabiting soft-bottom substrates throughout the Phanerozoic.

MicroRNA delivery for regenerative medicine.

PubMed

Peng, Bo; Chen, Yongming; Leong, Kam W

2015-07-01

MicroRNA (miRNA) directs post-transcriptional regulation of a network of genes by targeting mRNA. Although relatively recent in development, many miRNAs direct differentiation of various stem cells including induced pluripotent stem cells (iPSCs), a major player in regenerative medicine. An effective and safe delivery of miRNA holds the key to translating miRNA technologies. Both viral and nonviral delivery systems have seen success in miRNA delivery, and each approach possesses advantages and disadvantages. A number of studies have demonstrated success in augmenting osteogenesis, improving cardiogenesis, and reducing fibrosis among many other tissue engineering applications. A scaffold-based approach with the possibility of local and sustained delivery of miRNA is particularly attractive since the physical cues provided by the scaffold may synergize with the biochemical cues induced by miRNA therapy. Herein, we first briefly cover the application of miRNA to direct stem cell fate via replacement and inhibition therapies, followed by the discussion of the promising viral and nonviral delivery systems. Next we present the unique advantages of a scaffold-based delivery in achieving lineage-specific differentiation and tissue development. Copyright © 2015 Elsevier B.V. All rights reserved.

Burrowing hard corals occurring on the sea floor since 80 million years ago

NASA Astrophysics Data System (ADS)

Sentoku, Asuka; Tokuda, Yuki; Ezaki, Yoichi

2016-04-01

We describe a previously unknown niche for hard corals in the small, bowl-shaped, solitary scleractinian, Deltocyathoides orientalis (Family Turbinoliidae), on soft-bottom substrates. Observational experiments were used to clarify how the sea floor niche is exploited by turbinoliids. Deltocyathoides orientalis is adapted to an infaunal mode of life and exhibits behaviours associated with automobility that include burrowing into sediments, vertical movement through sediments to escape burial, and recovery of an upright position after being overturned. These behaviours were achieved through repeated expansion and contraction of their peripheral soft tissues, which constitute a unique muscle-membrane system. Histological analysis showed that these muscle arrangements were associated with deeply incised inter-costal spaces characteristic of turbinoliid corals. The oldest known turbinoliid, Bothrophoria ornata, which occurred in the Cretaceous (Campanian), also possessed a small, conical skeleton with highly developed costae. An infaunal mode of life became available to turbinoliids due to the acquisition of automobility through the muscle-membrane system at least 80 million years ago. The newly discovered active burrowing strategies described herein provide new insights into the use of an unattached mode of life by corals inhabiting soft-bottom substrates throughout the Phanerozoic.

Herbal Drugs from Sudan: Traditional Uses and Phytoconstituents

PubMed Central

Karar, Mohamed Gamaleldin Elsadig; Kuhnert, Nikolai

2017-01-01

Sudan folklore medicine is characterized by a unique combination of Islamic, Arabic, and African cultures. In poor communities, traditional medicine has remained as the most reasonable source of treatment of several diseases and microbial infections. Although the traditional medicine is accepted in Sudan, to date there is no updated review available, which focuses on most effective and frequently used Sudanese medicinal plants. Thus, this review aims to summarize the published information on the ethnobotanical uses of medicinal plants from Sudan, preparation methods, phytochemistry, and ethnopharmacology. The collected data demonstrate that Sudanese medicinal plants have been reported to possess a wide range of traditional medicinal uses including different microbial infections, gastrointestinal disorders, malaria, diabetes, rheumatic pain, respiratory system disorders, jaundice, urinary system inflammations, wounds, cancer, and different microbial infections. In most cases, the pharmacological studies were in agreement with traditional uses. Moreover, several bioactive compounds such as flavonoids, saponins, alkaloids, steroids, terpenes, tannins, fatty acids, and essential oils have been identified as active constituents. Although this review demonstrates the importance of ethnomedicine medicines in the treatment of several diseases in Sudan, further researches to validate the therapeutic uses and safety of these plants through phytochemical screening, different biological activity assays, and toxicological studies are still needed. PMID:28989244

Human uniqueness-self-interest and social cooperation.

PubMed

Okada, Daijiro; Bingham, Paul M

2008-07-21

Humans are unique among all species of terrestrial history in both ecological dominance and individual properties. Many, or perhaps all, of the unique elements of this nonpareil status can be plausibly interpreted as evolutionary and strategic elements and consequences of the unprecedented intensity and scale of our social cooperation. Convincing explanation of this unique human social adaptation remains a central, unmet challenge to the scientific enterprise. We develop a hypothesis for the ancestral origin of expanded cooperative social behavior. Specifically, we present a game theoretic analysis demonstrating that a specific pattern of expanded social cooperation between conspecific individuals with conflicts of interest (including non-kin) can be strategically viable, but only in animals that possess a highly unusual capacity for conspecific violence (credible threat) having very specific properties that dramatically reduce the costs of coercive violence. The resulting reduced costs allow preemptive or compensated coercion to be an instantaneously self-interested behavior under diverse circumstances rather than in rare, idiosyncratic circumstances as in actors (animals) who do not have access to inexpensive coercive threat. Humans are apparently unique among terrestrial organisms in having evolved conspecific coercive capabilities that fulfill these stringent requirements. Thus, our results support the proposal that access to a novel capacity for projection of coercive threat might represent the essential initiating event for the evolution of a human-like pattern of social cooperation and the subsequent evolution of the diverse features of human uniqueness. Empirical evidence indicates that these constraints were, in fact, met only in our evolutionary lineage. The logic for the emergence of uniquely human cooperation suggested by our analysis apparently accounts simply for the human fossil record.

Elastic metamaterials with simultaneously negative effective shear modulus and mass density.

PubMed

Wu, Ying; Lai, Yun; Zhang, Zhao-Qing

2011-09-02

We propose a type of elastic metamaterial comprising fluid-solid composite inclusions which can possess a negative shear modulus and negative mass density over a large frequency region. Such a material has the unique property that only transverse waves can propagate with a negative dispersion while longitudinal waves are forbidden. This leads to many interesting phenomena such as negative refraction, which is demonstrated by using a wedge sample and a significant amount of mode conversion from transverse waves to longitudinal waves that cannot occur on the interface of two natural solids.

Localization of 14-3-3 proteins in the nuclei of arabidopsis and maize.

PubMed

Bihn, E A; Paul, A L; Wang, S W; Erdos, G W; Ferl, R J

1997-12-01

It has been demonstrated that 14-3-3 proteins are present in the nuclei of Arabidopsis thaliana and Zea mays cells using laser scanning confocal microscopy and immunocytochemistry with monoclonal antibodies against plant 14-3-3 proteins. Confirmation of nuclear localization provides insight into the range of functions normally attributed to 14-3-3 proteins, especially since the association of 14-3-3s with transcription factors is (thus far) a phenomenon unique to plants, and since 14-3-3 proteins do not possess a recognizable nuclear targeting sequence.

Total synthesis and structural revision of TMG-chitotriomycin, a specific inhibitor of insect and fungal beta-N-acetylglucosaminidases.

PubMed

Yang, You; Li, Yao; Yu, Biao

2009-09-02

TMG-chitotriomycin, a potent and selective inhibitor of the beta-N-acetylglucosaminidases that possesses an unique N,N,N-trimethyl-d-glucosamine (TMG) residue, is revised to be the TMG-beta-(1-->4)-chitotriose instead of the originally proposed alpha-anomer via its total synthesis, for which a highly convergent approach was developed in which the sterically demanding (1-->4)-glycosidic linkages are efficiently constructed by the Au(I)-catalyzed glycosylation protocol with glycosyl o-hexynylbenzoates as donors.

Cajanusflavanols A-C, Three Pairs of Flavonostilbene Enantiomers from Cajanus cajan.

PubMed

He, Qi-Fang; Wu, Zhen-Long; Huang, Xiao-Jun; Zhong, Yuan-Lin; Li, Man-Mei; Jiang, Ren-Wang; Li, Yao-Lan; Ye, Wen-Cai; Wang, Ying

2018-02-02

Three pairs of new flavonostilbene enantiomers, cajanusflavanols A-C (1-3), along with their putative biogenetic precursors 4-6, were isolated from Cajanus cajan. Compound 1 possesses an unprecedented carbon skeleton featuring a unique highly functionalized cyclopenta[1,2,3-de]isobenzopyran-1-one tricyclic core. Compounds 2 and 3 are the first examples of methylene-unit-linked flavonostilbenes. Their structures with absolute configurations were elucidated by spectroscopic analyses, X-ray diffraction, and computational calculations. Compounds 1 and 2 exhibited significant in vitro anti-inflammatory activities.

Symmetric factorization of the conformation tensor in viscoelastic fluid models

NASA Astrophysics Data System (ADS)

Thomases, Becca; Balci, Nusret; Renardy, Michael; Doering, Charles

2010-11-01

The positive definite symmetric polymer conformation tensor possesses a unique symmetric square root that satisfies a closed evolution equation in the Oldroyd-B and FENE-P models of viscoelastic fluid flow. When expressed in terms of the velocity field and the symmetric square root of the conformation tensor, these models' equations of motion formally constitute an evolution in a Hilbert space with a total energy functional that defines a norm. Moreover, this formulation is easily implemented in direct numerical simulations resulting in significant practical advantages in terms of both accuracy and stability.

Dynamical structure of pure Lovelock gravity

NASA Astrophysics Data System (ADS)

Dadhich, Naresh; Durka, Remigiusz; Merino, Nelson; Miskovic, Olivera

2016-03-01

We study the dynamical structure of pure Lovelock gravity in spacetime dimensions higher than four using the Hamiltonian formalism. The action consists of a cosmological constant and a single higher-order polynomial in the Riemann tensor. Similarly to the Einstein-Hilbert action, it possesses a unique constant curvature vacuum and charged black hole solutions. We analyze physical degrees of freedom and local symmetries in this theory. In contrast to the Einstein-Hilbert case, the number of degrees of freedom depends on the background and can vary from zero to the maximal value carried by the Lovelock theory.

AnilinoMethylRhodamines: pH Sensitive Probes with Tunable Photophysical Properties by Substituent Effect

PubMed Central

Best, Quinn A.; Liu, Chuangjun; van Hoveln, Paul D.; McCarroll, Matthew E.

2013-01-01

A series of pH dependent rhodamine analogs possessing an anilino-methyl moiety was developed and shown to exhibit a unique photophysical response to pH. These Anilinomethylrhodamines (AnMR) maintain a colorless, non-fluorescent spiro-cyclic structure at high pH. The spiro-cyclic structures open in mildly acidic conditions and are weakly fluorescent; however at very low pH, the fluorescence is greatly enhanced. The equilibrium constants of these processes show a linear response to substituent effects, which was demonstrated by the Hammett equation. PMID:24050117

The effect of playing tactics and situational variables on achieving score-box possessions in a professional soccer team.

PubMed

Lago-Ballesteros, Joaquin; Lago-Peñas, Carlos; Rey, Ezequiel

2012-01-01

The aim of this study was to analyse the influence of playing tactics, opponent interaction and situational variables on achieving score-box possessions in professional soccer. The sample was constituted by 908 possessions obtained by a team from the Spanish soccer league in 12 matches played during the 2009-2010 season. Multidimensional qualitative data obtained from 12 ordered categorical variables were used. Sampled matches were registered by the AMISCO PRO system. Data were analysed using chi-square analysis and multiple logistic regression analysis. Of 908 possessions, 303 (33.4%) produced score-box possessions, 477 (52.5%) achieved progression and 128 (14.1%) failed to reach any sort of progression. Multiple logistic regression showed that, for the main variable "team possession type", direct attacks and counterattacks were three times more effective than elaborate attacks for producing a score-box possession (P < 0.05). Team possession originating from the middle zones and playing against less than six defending players (P < 0.001) registered a higher success than those started in the defensive zone with a balanced defence. When the team was drawing or winning, the probability of reaching the score-box decreased by 43 and 53 percent, respectively, compared with the losing situation (P < 0.05). Accounting for opponent interactions and situational variables is critical to evaluate the effectiveness of offensive playing tactics on producing score-box possessions.

Unique metabolites protect earthworms against plant polyphenols.

PubMed

Liebeke, Manuel; Strittmatter, Nicole; Fearn, Sarah; Morgan, A John; Kille, Peter; Fuchser, Jens; Wallis, David; Palchykov, Vitalii; Robertson, Jeremy; Lahive, Elma; Spurgeon, David J; McPhail, David; Takáts, Zoltán; Bundy, Jacob G

2015-08-04

All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term 'drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide.

Inventory of Anchialine Pools in Hawaii's National Parks

USGS Publications Warehouse

Foote, David

2005-01-01

BACKGROUND Anchialine (?near the sea?) pools are rare and localized brackish waters along coastal lava flows that exhibit tidal fluctuations without a surface connection with the ocean (Fig. 1). In Hawai`i, these pools were frequently excavated or otherwise modified by Hawaiians to serve as sources of drinking water, baths and fish ponds. National Parks in Hawai`i possess the full spectrum of pool types, from walled fish ponds to undisturbed pools in collapsed lava tubes, cracks and caves. Pools contain relatively rare and unique fauna threatened primarily by invasive species and habitat loss. In collaboration with the National Park Service?s Inventory and Monitoring Program, the U.S. Geological Survey?s Pacific Island Ecosystems Research Center undertook inventories of these unique ecosystems in two National Parks on the island of Hawai`i: Hawai`i Volcanoes National Park and Kaloko-Honokohau National Historical Park.

Unique Chiral Interpenetrating d-f Heterometallic MOFs as Luminescent Sensors.

PubMed

Wu, Zhi-Lei; Dong, Jie; Ni, Wei-Yan; Zhang, Bo-Wen; Cui, Jian-Zhong; Zhao, Bin

2015-06-01

One novel three-dimensional (3D) 3d-4f metal-organic framework (MOF), [TbZn(L)(CO3)2(H2O)]n (1) [HL = 4'-(4-carboxyphenyl)-2,2':6',2″-terpyridine], has been successfully synthesized and structurally characterized. Structural analysis shows that compound 1 features a unique chiral interpenetrating 3D framework for the first time. The resulting crystals of 1 are composed of enantiomers 1a (P41) and 1b (P43), as was clearly confirmed by the crystal structure and the corresponding circular dichroism (CD) analyses of eight randomly selected crystals. The investigations on CD spectra based on every single crystal clearly assigned the Cotton effect signals. The powder X-ray diffraction measurement of 1 after being immersed in common solvents reveals that 1 possess excellent solvent stability. Furthermore, luminescent studies imply that 1 displays highly selective luminescent sensing of aldehydes, such as formol, acetaldehyde, and propanal.

Growth and quantum transport properties of vertical Bi2Se3 nanoplate films on Si substrates.

PubMed

Li, Mingze; Wang, Zhenhua; Yang, Liang; Pan, Desheng; Li, Da; Gao, Xuan P A; Zhang, Zhidong

2018-08-03

Controlling the growth direction (planar versus vertical) and surface-to-bulk ratio can lead to lots of unique properties for two-dimensional layered materials. We report a simple method to fabricate continuous films of vertical Bi 2 Se 3 nanoplates on Si substrate and investigate the quantum transport properties of such films. In contrast to (001) oriented planar Bi 2 Se 3 nanoplate film, vertical Bi 2 Se 3 nanoplate films are enclosed by (015) facets, which possess high surface-to-bulk ratio that can enhance the quantum transport property of topological surface states. And by controlling the compactness of vertical Bi 2 Se 3 nanoplates, we realized an effective tuning of the weak antilocalization effect from topological surface states in Bi 2 Se 3 films. Our work paves a way for exploring the unique transport properties of this unconventional structure topological insulator film.

Synthesis and biological evaluations of a series of thaxtomin analogues.

PubMed

Zhang, Hongbo; Wang, Qingpeng; Ning, Xin; Hang, Hang; Ma, Jing; Yang, Xiande; Lu, Xiaolin; Zhang, Jiabao; Li, Yonghong; Niu, Congwei; Song, Haoran; Wang, Xin; Wang, Peng George

2015-04-15

Thaxtomins are a unique family of phytotoxins with unique 4-nitroindole and diketopiperazine fragments possessing potential herbicidal activities. This work presents the total synthesis of natural product thaxtomin C and its analogues. The extensive structure-activity relationship study screens four effective compounds, including thaxtomin A and thaxtomin C. It is indicated that 4-nitro indole fragment is essential for phytotoxicity, while benzyl and m-hydroxybenzyl substituents on the diketopiperazine ring are favorable for the efficacy. The N-methylations on indole and diketopiperazine show weak influence on the herbicidal activities. The four selected compounds show effective herbicidal activities against Brassica campestris, Amaranthus retroflexus, and Abutilon theophrasti, which are comparable or better than dichlobenil, even at a dosage of 187.5 g ha(-1). Moreover, these four compounds show good crop-selective properties to different crops and exhibit moderate protoporphyrinogen oxidase (PPO) enzyme inhibition. The antifungal results indicate that thaxtomin C displays inhibition to a wide range of fungi.

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

Mehboob, Shahila; Hevener, Kirk E.; Truong, Kent

Because of structural and mechanistic differences between eukaryotic and prokaryotic fatty acid synthesis enzymes, the bacterial pathway, FAS-II, is an attractive target for the design of antimicrobial agents. We have previously reported the identification of a novel series of benzimidazole compounds with particularly good antibacterial effect against Francisella tularensis, a Category A biowarfare pathogen. Herein we report the crystal structure of the F. tularensis FabI enzyme in complex with our most active benzimidazole compound bound with NADH. The structure reveals that the benzimidazole compounds bind to the substrate site in a unique conformation that is distinct from the binding motifmore » of other known FabI inhibitors. Detailed inhibition kinetics have confirmed that the compounds possess a novel inhibitory mechanism that is unique among known FabI inhibitors. These studies could have a strong impact on future antimicrobial design efforts and may reveal new avenues for the design of FAS-II active antibacterial compounds.« less

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

Jiang, J.; Liu, Z. K.; Sun, Y.

Topological Weyl semimetal (TWS), a new state of quantum matter, has sparked enormous research interest recently. Possessing unique Weyl fermions in the bulk and Fermi arcs on the surface, TWSs offer a rare platform for realizing many exotic physical phenomena. TWSs can be classified into type-I that respect Lorentz symmetry and type-II that do not. Here, we directly visualize the electronic structure of MoTe 2, a recently proposed type-II TWS. Using angle-resolved photoemission spectroscopy (ARPES), we unravel the unique surface Fermi arcs, in good agreement with our ab initio calculations that have nontrivial topological nature. Our work not only leadsmore » to new understandings of the unusual properties discovered in this family of compounds, but also allows for the further exploration of exotic properties and practical applications of type-II TWSs, as well as the interplay between superconductivity (MoTe 2 was discovered to be superconducting recently) and their topological order.« less

Terpenoid-Alkaloids: Their Biosynthetic Twist of Fate and Total Synthesis.

PubMed

Cherney, Emily C; Baran, Phil S

2011-04-01

Terpenes and alkaloids are ever-growing classes of natural products that provide new molecular structures which inspire chemists and possess a broad range of biological activity. Terpenoid-alkaloids originate from the same prenyl units that construct terpene skeletons. However, during biosynthesis, a nitrogen atom (or atoms) is introduced in the form of β-aminoethanol, ethylamine, or methylamine. Nitrogen incorporation can occur either before, during, or after the cyclase phase. The outcome of this unique biosynthesis is the formation of natural products containing unprecedented structures. These complex structural motifs expose current limitations in organic chemistry, thus providing opportunities for invention. This review focuses on total syntheses of terpenoid-alkaloids and unique issues presented by this class of natural products. More specifically, it examines how these syntheses relate to the way terpenoid-alkaloids are made in Nature. Developments in chemistry that have facilitated these syntheses are emphasized, as well as chemical technology needed to conquer those that evade synthesis.

Signature of Type-II Weyl Semimetal Phase in MoTe2

NASA Astrophysics Data System (ADS)

Jiang, Juan; Liu, Zhongkai; Yang, Haifeng; Yang, Lexian; Chen, Cheng; Peng, Han; Hwang, Chan-Cuk; Mo, Sung-Kwan; Chen, Yulin; ShanghaiTech University Collaboration; Oxford University Collaboration; Lawrence Berkeley National Lab Collaboration; Pohang University of Science; Technology Collaboration

Topological Weyl semimetal (TWS) is a new state of quantum matter, which has sparked enormous research interest recently. Possessing unique Weyl fermions in the bulk and Fermi arcs on the surface, TWSs offer a rare platform for realizing many exotic physical phenomena. Here, by using angle-resolved photoemission spectroscopy, we directly visualize the electronic structure of MoTe2, a recently proposed type-II TWS, which do not respect Lorentz symmetry compared with type-I TWS. Furthermore, we unravel the unique surface Fermi arcs, in good agreement with our ab-initio calculations, which have non-trivial topological nature. Our work not only leads to new understandings of the unusual properties discovered in this family of compounds, but also allows for the further exploration of exotic properties and practical applications of type-II TWSs, as well as the interplay between superconductivity and their topological order.

Signature of type-II Weyl semimetal phase in MoTe2

NASA Astrophysics Data System (ADS)

Jiang, J.; Liu, Z. K.; Sun, Y.; Yang, H. F.; Rajamathi, C. R.; Qi, Y. P.; Yang, L. X.; Chen, C.; Peng, H.; Hwang, C.-C.; Sun, S. Z.; Mo, S.-K.; Vobornik, I.; Fujii, J.; Parkin, S. S. P.; Felser, C.; Yan, B. H.; Chen, Y. L.

2017-01-01

Topological Weyl semimetal (TWS), a new state of quantum matter, has sparked enormous research interest recently. Possessing unique Weyl fermions in the bulk and Fermi arcs on the surface, TWSs offer a rare platform for realizing many exotic physical phenomena. TWSs can be classified into type-I that respect Lorentz symmetry and type-II that do not. Here, we directly visualize the electronic structure of MoTe2, a recently proposed type-II TWS. Using angle-resolved photoemission spectroscopy (ARPES), we unravel the unique surface Fermi arcs, in good agreement with our ab initio calculations that have nontrivial topological nature. Our work not only leads to new understandings of the unusual properties discovered in this family of compounds, but also allows for the further exploration of exotic properties and practical applications of type-II TWSs, as well as the interplay between superconductivity (MoTe2 was discovered to be superconducting recently) and their topological order.

14. Photograph of a photograph in possession of the Watervliet ...

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

14. Photograph of a photograph in possession of the Watervliet Arsenal Museum, New York. CONSTRUCTION PHOTOGRAPH SHOWING CAST IRON TRUSS SYSTEM IN WHAT IS PROBABLY UNIT 2. TAKEN IN 1865. - Watervliet Arsenal, Building No. 40, Broadway between Dalliba & Watervliet Avenues, Watervliet, Albany County, NY

The Protein Kingdom Extended: Ordered and Intrinsically Disordered Proteins, Their Folding, Supramolecular Complex Formation, and Aggregation

PubMed Central

Turoverov, Konstantin K.; Kuznetsova, Irina M.; Uversky, Vladimir N.

2010-01-01

The native state of a protein is usually associated with a compact globular conformation possessing a rigid and highly ordered structure. At the turn of the last century certain studies arose which concluded that many proteins cannot, in principle, form a rigid globular structure in an aqueous environment, but they are still able to fulfill their specific functions — i.e., they are native. The existence of the disordered regions allows these proteins to interact with their numerous binding partners. Such interactions are often accompanied by the formation of complexes that possess a more ordered structure than the original components. The functional diversity of these proteins, combined with the variability of signals related to the various intra-and intercellular processes handled by these proteins and their capability to produce multi-variant and multi-directional responses allow them to form a unique regulatory net in a cell. The abundance of disordered proteins inside the cell is precisely controlled at the synthesis and clearance levels as well as via interaction with specific binding partners and posttranslational modifications. Another recently recognized biologically active state of proteins is the functional amyloid. The formation of such functional amyloids is tightly controlled and therefore differs from the uncontrolled formation of pathogenic amyloids which are associated with the pathogenesis of several conformational diseases, the development of which is likely to be determined by the failures of the cellular regulatory systems rather than by the formation of the proteinaceous deposits and/or by the protofibril toxicity. PMID:20097220

Granular biodurable nanomaterials: No convincing evidence for systemic toxicity.

PubMed

Moreno-Horn, Marcus; Gebel, Thomas

2014-11-01

Nanomaterials are usually defined by primary particle diameters ranging from 1 to 100 nm. The scope of this review is an evaluation of experimental animal studies dealing with the systemic levels and putative systemic effects induced by nanoparticles which can be characterized as being granular biodurable particles without known specific toxicity (GBP). Relevant examples of such materials comprise nanosized titanium dioxide (TiO2) and carbon black. The question was raised whether GBP nanomaterials systemically accumulate and may possess a relevant systemic toxicity. With few exceptions, the 56 publications reviewed were not performed using established standard protocols, for example, OECD guidelines but used non-standard study designs. The studies including kinetic investigations indicated that GBP nanomaterials were absorbed and systemically distributed to rather low portions only. There was no valid indication that GPB nanomaterials possess novel toxicological hazard properties. In addition, no convincing evidence for a relevant specific systemic toxicity of GBP nanomaterials could be identified. The minority of the papers reviewed (15/56) investigated both nanosized and microsized GBP materials in parallel. A relevant different translocation of GBP nanomaterials in contrast to GBP micromaterials was not observed in these studies. There was no evidence that GPB nanomaterials possess toxicological properties other than their micromaterial counterparts.

The Sus operon: a model system for starch uptake by the human gut Bacteroidetes

PubMed Central

Foley, Matthew H.; Cockburn, Darrell W.; Koropatkin, Nicole M.

2016-01-01

Resident bacteria in the densely populated human intestinal tract must efficiently compete for carbohydrate nutrition. The Bacteroidetes, a dominant bacterial phylum in the mammalian gut, encode a plethora of discrete polysaccharide utilization loci (PULs) that are selectively activated to facilitate glycan capture at the cell surface. The most well-studied PUL-encoded glycan-up-take system is the starch utilization system (Sus) of Bacteroides thetaiotaomicron. The Sus includes the requisite proteins for binding and degrading starch at the surface of the cell preceding oligosaccharide transport across the outer membrane for further depolymerization to glucose in the periplasm. All mammalian gut Bacteroidetes possess analogous Sus-like systems that target numerous diverse glycans. In this review, we discuss what is known about the eight Sus proteins of B. thetaiotaomicron that define the Sus-like paradigm of nutrient acquisition that is exclusive to the Gram-negative Bacteroidetes. We emphasize the well-characterized outer membrane proteins SusDEF and the α-amylase SusG, each of which have unique structural features that allow them to interact with starch on the cell surface. Despite the apparent redundancy in starch-binding sites among these proteins, each has a distinct role during starch catabolism. Additionally, we consider what is known about how these proteins dynamically interact and cooperate in the membrane and propose a model for the formation of the Sus outer membrane complex. PMID:27137179

Minimizing Human Risk: Human Performance Models in the Human Factors and Behavioral Performance Element

NASA Technical Reports Server (NTRS)

Gore, Brian F.

2017-01-01

Human space exploration has never been more exciting than it is today. Human presence to outer worlds is becoming a reality as humans are leveraging much of our prior knowledge to the new mission of going to Mars. Exploring the solar system at greater distances from Earth than ever before will possess some unique challenges, which can be overcome thanks to the advances in modeling and simulation technologies. The National Aeronautics and Space Administration (NASA) is at the forefront of exploring our solar system. NASA's Human Research Program (HRP) focuses on discovering the best methods and technologies that support safe and productive human space travel in the extreme and harsh space environment. HRP uses various methods and approaches to answer questions about the impact of long duration missions on the human in space including: gravitys impact on the human body, isolation and confinement on the human, hostile environments impact on the human, space radiation, and how the distance is likely to impact the human. Predictive models are included in the HRP research portfolio as these models provide valuable insights into human-system operations. This paper will provide an overview of NASA's HRP and will present a number of projects that have used modeling and simulation to provide insights into human-system issues (e.g. automation, habitat design, schedules) in anticipation of space exploration.

Minimizing Human Risk: Human Performance Models in the Space Human Factors and Habitability and Behavioral Health and Performance Elements

NASA Technical Reports Server (NTRS)

Gore, Brian F.

2016-01-01

Human space exploration has never been more exciting than it is today. Human presence to outer worlds is becoming a reality as humans are leveraging much of our prior knowledge to the new mission of going to Mars. Exploring the solar system at greater distances from Earth than ever before will possess some unique challenges, which can be overcome thanks to the advances in modeling and simulation technologies. The National Aeronautics and Space Administration (NASA) is at the forefront of exploring our solar system. NASA's Human Research Program (HRP) focuses on discovering the best methods and technologies that support safe and productive human space travel in the extreme and harsh space environment. HRP uses various methods and approaches to answer questions about the impact of long duration missions on the human in space including: gravity's impact on the human body, isolation and confinement on the human, hostile environments impact on the human, space radiation, and how the distance is likely to impact the human. Predictive models are included in the HRP research portfolio as these models provide valuable insights into human-system operations. This paper will provide an overview of NASA's HRP and will present a number of projects that have used modeling and simulation to provide insights into human-system issues (e.g. automation, habitat design, schedules) in anticipation of space exploration.

Planetary Rings

NASA Astrophysics Data System (ADS)

Gordon, M. K.; Araki, S.; Black, G. J.; Bosh, A. S.; Brahic, A.; Brooks, S. M.; Charnoz, S.; Colwell, J. E.; Cuzzi, J. N.; Dones, L.; Durisen, R. H.; Esposito, L. W.; Ferrari, C.; Festou, M.; French, R. G.; Giuliatti-Winter, S. M.; Graps, A. L.; Hamilton, D. P.; Horanyi, M.; Karjalainen, R. M.; Krivov, A. V.; Krueger, H.; Larson, S. M.; Levison, H. F.; Lewis, M. C.; Lissauer, J. J.; Murray, C. D.; Namouni, F.; Nicholson, P. D.; Olkin, C. B.; Poulet, F.; Rappaport, N. J.; Salo, H. J.; Schmidt, J.; Showalter, M. R.; Spahn, F.; Spilker, L. J.; Srama, R.; Stewart, G. R.; Yanamandra-Fisher, P.

2002-08-01

The past two decades have witnessed dramatic changes in our view and understanding of planetary rings. We now know that each of the giant planets in the Solar System possesses a complex and unique ring system. Recent studies have identified complex gravitational interactions between the rings and their retinues of attendant satellites. Among the four known ring systems, we see elegant examples of Lindblad and corotation resonances (first invoked in the context of galactic disks), electromagnetic resonances, spiral density waves and bending waves, narrow ringlets which exhibit internal modes due to collective instabilities, sharp-edged gaps maintained via tidal torques from embedded moonlets, and tenuous dust belts created by meteoroid impact onto, or collisions between, parent bodies. Yet, as far as we have come, our understanding is far from complete. The fundamental questions confronting ring scientists at the beginning of the twenty-first century are those regarding the origin, age and evolution of the various ring systems, in the broadest context. Understanding the origin and age requires us to know the current ring properties, and to understand the dominant evolutionary processes and how they influence ring properties. Here we discuss a prioritized list of the key questions, the answers to which would provide the greatest improvement in our understanding of planetary rings. We then outline the initiatives, missions, and other supporting activities needed to address those questions, and recommend priorities for the coming decade in planetary ring science.

Smart materials systems through mesoscale patterning

NASA Astrophysics Data System (ADS)

Aksay, Ilhan A.; Groves, John T.; Gruner, Sol M.; Lee, P. C. Y.; Prud'homme, Robert K.; Shih, Wei-Heng; Torquato, Salvatore; Whitesides, George M.

1996-02-01

We report work on the fabrication of smart materials with two unique strategies: (1) self- assembly and (2) laser stereolithography. Both methods are akin to the processes used by biological systems. The first one is ideal for pattern development and the fabrication of miniaturized units in the submicron range and the second one in the 10 micrometer to 1 mm size range. By using these miniaturized units as building blocks, one can also produce smart material systems that can be used at larger length scales such as smart structural components. We have chosen to focus on two novel piezoceramic systems: (1) high-displacement piezoelectric actuators, and (2) piezoceramic hydrophone composites possessing negative Poisson ratio matrices. High-displacement actuators are essential in such applications as linear motors, pumps, switches, loud speakers, variable-focus mirrors, and laser deflectors. Arrays of such units can potentially be used for active vibration control of helicopter rotors as well as the fabrication of adaptive rotors. In the case of piezoceramic hydrophone composites, we utilize matrices having a negative Poisson's ratio in order to produce highly sensitive, miniaturized sensors. We envision such devices having promising new application areas such as the implantation of hydrophones in small blood vessels to monitor blood pressure. Negative Poisson ratio materials have promise as robust shock absorbers, air filters, and fasteners, and hence, can be used in aircraft and land vehicles.

Ultrahigh Sensitive and Flexible Magnetoelectronics with Magnetic Nanocomposites: Toward an Additional Perception of Artificial Intelligence.

PubMed

Cai, Shu-Yi; Chang, Cheng-Han; Lin, Hung-I; Huang, Yuan-Fu; Lin, Wei-Ju; Lin, Shih-Yao; Liou, Yi-Rou; Shen, Tien-Lin; Huang, Yen-Hsiang; Tsao, Po-Wei; Tzou, Chen-Yang; Liao, Yu-Ming; Chen, Yang-Fang

2018-05-23

In recent years, flexible magnetoelectronics has attracted a great attention for its intriguing functionalities and potential applications, such as healthcare, memory, soft robots, navigation, and touchless human-machine interaction systems. Here, we provide the first attempt to demonstrate a new type of magneto-piezoresistance device, which possesses an ultrahigh sensitivity with several orders of resistance change under an external magnetic field (100 mT). In our device, Fe-Ni alloy powders are embedded in the silver nanowire-coated micropyramid polydimethylsiloxane films. Our devices can not only serve as an on/off switch but also act as a sensor that can detect different magnetic fields because of its ultrahigh sensitivity, which is very useful for the application in analog signal communication. Moreover, our devices contain several key features, including large-area and easy fabrication processes, fast response time, low working voltage, low power consumption, excellent flexibility, and admirable compatibility onto a freeform surface, which are the critical criteria for the future development of touchless human-machine interaction systems. On the basis of all of these unique characteristics, we have demonstrated a nontouch piano keyboard, instantaneous magnetic field visualization, and autonomous power system, making our new devices be integrable with magnetic field and enable to be implemented into our daily life applications with unfamiliar human senses. Our approach therefore paves a useful route for the development of wearable electronics and intelligent systems.

Nerve Conduction Through Dendrites via Proton Hopping.

PubMed

Kier, Lemont B

2017-01-01

In our previous studies of nerve conduction conducted by proton hopping, we have considered the axon, soma, synapse and the nodes of Ranvier. The role of proton hopping described the passage of information through each of these units of a typical nerve system. The synapse projects information from the axon to the dendrite and their associated spines. We have invoked the passage of protons via a hopping mechanism to illustrate the continuum of the impulse through the system, via the soma following the dendrites. This is proposed to be a continuum invoked by the proton hopping method. With the proposal of the activity through the dendrites, via proton hopping, a complete model of the nerve function is invoked. At each step to the way, a water pathway is present and is invoked in the proposed model as the carrier of the message via proton hopping. The importance of the dendrites is evident by the presence of a vast number of spines, each possessing the possibility to carry unique messages through the nervous system. With this model of the role of dendrites, functioning with the presence of proton hopping, a complete model of the nerve system is presented. The validity of this model will be available for further studies and models to assess it's validity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Neural mechanisms of decision making in hoarding disorder.

PubMed

Tolin, David F; Stevens, Michael C; Villavicencio, Anna L; Norberg, Melissa M; Calhoun, Vince D; Frost, Randy O; Steketee, Gail; Rauch, Scott L; Pearlson, Godfrey D

2012-08-01

Hoarding disorder (HD), previously considered a subtype of obsessive-compulsive disorder (OCD), has been proposed as a unique diagnostic entity in DSM-5. Current models of HD emphasize problems of decision-making, attachment to possessions, and poor insight, whereas previous neuroimaging studies have suggested abnormalities in frontal brain regions. To examine the neural mechanisms of impaired decision making in HD in patients with well-defined primary HD compared with patients with OCD and healthy control subjects (HCs). We compared neural activity among patients with HD, patients with OCD, and HCs during decisions to keep or discard personal possessions and control possessions from November 9, 2006, to August 13, 2010. Private, not-for-profit hospital. A total of 107 adults (43 with HD, 31 with OCD, and 33 HCs). Neural activity as measured by functional magnetic resonance imaging in which actual real-time and binding decisions had to be made about whether to keep or discard possessions. Compared with participants with OCD and HC, participants with HD exhibited abnormal activity in the anterior cingulate cortex and insula that was stimulus dependent. Specifically, when deciding about items that did not belong to them, patients with HD showed relatively lower activity in these brain regions. However, when deciding about items that belonged to them, these regions showed excessive functional magnetic resonance imaging signals compared with the other 2 groups. These differences in neural function correlated significantly with hoarding severity and self-ratings of indecisiveness and "not just right" feelings among patients with HD and were unattributable to OCD or depressive symptoms. Findings suggest a biphasic abnormality in anterior cingulate cortex and insula function in patients with HD related to problems in identifying the emotional significance of a stimulus, generating appropriate emotional response, or regulating affective state during decision making.

Syncytia in plants: cell fusion in endosperm-placental syncytium formation in Utricularia (Lentibulariaceae).

PubMed

Płachno, Bartosz J; Swiątek, Piotr

2011-04-01

The syncytium formed by Utricularia is extremely unusual and perhaps unique among angiosperm syncytia. All typical plant syncytia (articulated laticifers, amoeboid tapetum, the nucellar plasmodium of river weeds) are formed only by fusion of sporophytic cells which possess the same genetic material, unlike Utricularia in which the syncytium possesses nuclei from two different sources: cells of maternal sporophytic nutritive tissue and endosperm haustorium (both maternal and paternal genetic material). How is this kind of syncytium formed and organized and is it similar to other plant syncytial structures? We used light and electron microscopy to reconstruct the step-by-step development of the Utricularia syncytia. The syncytia of Utricularia developed through heterotypic cell fusion involving the digestion of the cell wall, and finally, heterokaryotic multinucleate structures were formed, which possessed different-sized nuclei that were not regularly arranged in the cytoplasm. We showed that these syncytia were characterized by hypertrophy of nuclei, abundant endoplasmic reticulum and organelles, and the occurrence of wall ingrowths. All these characters testify to high activity and may confirm the nutritive and transport functions of the syncytium for the developing embryo. In Utricularia, the formation of the syncytium provides an economical way to redistribute cell components and release nutrients from the digested cell walls, which can now be used for the embryo, and finally to create a large surface for the exchange of nutrients between the placenta and endosperm.

Collagen-Gold Nanoparticle Conjugates for Versatile Biosensing

PubMed Central

Unser, Sarah; Holcomb, Samuel; Cary, ReJeana; Sagle, Laura

2017-01-01

Integration of noble metal nanoparticles with proteins offers promising potential to create a wide variety of biosensors that possess both improved selectivity and versatility. The multitude of functionalities that proteins offer coupled with the unique optical properties of noble metal nanoparticles can allow for the realization of simple, colorimetric sensors for a significantly larger range of targets. Herein, we integrate the structural protein collagen with 10 nm gold nanoparticles to develop a protein-nanoparticle conjugate which possess the functionality of the protein with the desired colorimetric properties of the nanoparticles. Applying the many interactions that collagen undergoes in the extracellular matrix, we are able to selectively detect both glucose and heparin with the same collagen-nanoparticle conjugate. Glucose is directly detected through the cross-linking of the collagen fibrils, which brings the attached nanoparticles into closer proximity, leading to a red-shift in the LSPR frequency. Conversely, heparin is detected through a competition assay in which heparin-gold nanoparticles are added to solution and compete with heparin in the solution for the binding sites on the collagen fibrils. The collagen-nanoparticle conjugates are shown to detect both glucose and heparin in the physiological range. Lastly, glucose is selectively detected in 50% mouse serum with the collagen-nanoparticle devices possessing a linear range of 3–25 mM, which is also within the physiologically relevant range. PMID:28212282

Draft Genome Sequencing and Comparative Analysis of Aspergillus sojae NBRC4239

PubMed Central

Sato, Atsushi; Oshima, Kenshiro; Noguchi, Hideki; Ogawa, Masahiro; Takahashi, Tadashi; Oguma, Tetsuya; Koyama, Yasuji; Itoh, Takehiko; Hattori, Masahira; Hanya, Yoshiki

2011-01-01

We conducted genome sequencing of the filamentous fungus Aspergillus sojae NBRC4239 isolated from the koji used to prepare Japanese soy sauce. We used the 454 pyrosequencing technology and investigated the genome with respect to enzymes and secondary metabolites in comparison with other Aspergilli sequenced. Assembly of 454 reads generated a non-redundant sequence of 39.5-Mb possessing 13 033 putative genes and 65 scaffolds composed of 557 contigs. Of the 2847 open reading frames with Pfam domain scores of >150 found in A. sojae NBRC4239, 81.7% had a high degree of similarity with the genes of A. oryzae. Comparative analysis identified serine carboxypeptidase and aspartic protease genes unique to A. sojae NBRC4239. While A. oryzae possessed three copies of α-amyalse gene, A. sojae NBRC4239 possessed only a single copy. Comparison of 56 gene clusters for secondary metabolites between A. sojae NBRC4239 and A. oryzae revealed that 24 clusters were conserved, whereas 32 clusters differed between them that included a deletion of 18 508 bp containing mfs1, mao1, dmaT, and pks-nrps for the cyclopiazonic acid (CPA) biosynthesis, explaining the no productivity of CPA in A. sojae. The A. sojae NBRC4239 genome data will be useful to characterize functional features of the koji moulds used in Japanese industries. PMID:21659486

Nutrient Acquisition and Metabolism by Campylobacter jejuni

PubMed Central

Stahl, Martin; Butcher, James; Stintzi, Alain

2012-01-01

The gastrointestinal pathogen Campylobacter jejuni is able to colonize numerous different hosts and compete against the gut microbiota. To do this, it must be able to efficiently acquire sufficient nutrients from its environment to support its survival and rapid growth in the intestine. However, despite almost 50 years of research, many aspects as to how C. jejuni accomplishes this feat remain poorly understood. C. jejuni lacks many of the common metabolic pathways necessary for the use of glucose, galactose, or other carbohydrates upon which most other microbes thrive. It does however make efficient use of citric acid cycle intermediates and various amino acids. C. jejuni readily uses the amino acids aspartate, glutamate, serine, and proline, with certain strains also possessing additional pathways allowing for the use of glutamine and asparagine. More recent work has revealed that some C. jejuni strains can metabolize the sugar l-fucose. This finding has upset years of dogma that C. jejuni is an asaccharolytic organism. C. jejuni also possesses diverse mechanisms for the acquisition of various transition metals that are required for metabolic activities. In particular, iron acquisition is critical for the formation of iron–sulfur complexes. C. jejuni is also unique in possessing both molybdate and tungsten cofactored proteins and thus has an unusual regulatory scheme for these metals. Together these various metabolic and acquisition pathways help C. jejuni to compete and thrive in wide variety of hosts and environments. PMID:22919597

Brucella papionis sp. nov., isolated from baboons (Papio spp.)

PubMed Central

Davison, Nicholas; Cloeckaert, Axel; Al Dahouk, Sascha; Zygmunt, Michel S.; Brew, Simon D.; Perrett, Lorraine L.; Koylass, Mark S.; Vergnaud, Gilles; Quance, Christine; Scholz, Holger C.; Dick, Edward J.; Hubbard, Gene; Schlabritz-Loutsevitch, Natalia E.

2014-01-01

Two Gram-negative, non-motile, non-spore-forming coccoid bacteria (strains F8/08-60T and F8/08-61) isolated from clinical specimens obtained from baboons (Papio spp.) that had delivered stillborn offspring were subjected to a polyphasic taxonomic study. On the basis of 16S rRNA gene sequence similarities, both strains, which possessed identical sequences, were assigned to the genus Brucella. This placement was confirmed by extended multilocus sequence analysis (MLSA), where both strains possessed identical sequences, and whole-genome sequencing of a representative isolate. All of the above analyses suggested that the two strains represent a novel lineage within the genus Brucella. The strains also possessed a unique profile when subjected to the phenotyping approach classically used to separate species of the genus Brucella, reacting only with Brucella A monospecific antiserum, being sensitive to the dyes thionin and fuchsin, being lysed by bacteriophage Wb, Bk2 and Fi phage at routine test dilution (RTD) but only partially sensitive to bacteriophage Tb, and with no requirement for CO2 and no production of H2S but strong urease activity. Biochemical profiling revealed a pattern of enzyme activity and metabolic capabilities distinct from existing species of the genus Brucella. Molecular analysis of the omp2 locus genes showed that both strains had a novel combination of two highly similar omp2b gene copies. The two strains shared a unique fingerprint profile of the multiple-copy Brucella-specific element IS711. Like MLSA, a multilocus variable number of tandem repeat analysis (MLVA) showed that the isolates clustered together very closely, but represent a distinct group within the genus Brucella. Isolates F8/08-60T and F8/08-61 could be distinguished clearly from all known species of the genus Brucellaand their biovars by both phenotypic and molecular properties. Therefore, by applying the species concept for the genus Brucellasuggested by the ICSP Subcommittee on the Taxonomy of Brucella, they represent a novel species within the genus Brucella, for which the name Brucella papionis sp. nov. is proposed, with the type strain F8/08-60T ( = NCTC 13660T = CIRMBP 0958T). PMID:25242540

Down syndrome: Cognitive and behavioral functioning across the lifespan.

PubMed

Grieco, Julie; Pulsifer, Margaret; Seligsohn, Karen; Skotko, Brian; Schwartz, Alison

2015-06-01

Individuals with Down syndrome (DS) commonly possess unique neurocognitive and neurobehavioral profiles that emerge within specific developmental periods. These profiles are distinct relative to others with similar intellectual disability (ID) and reflect underlying neuroanatomic findings, providing support for a distinctive phenotypic profile. This review updates what is known about the cognitive and behavioral phenotypes associated with DS across the lifespan. In early childhood, mild deviations from neurotypically developing trajectories emerge. By school-age, delays become pronounced. Nonverbal skills remain on trajectory for mental age, whereas verbal deficits emerge and persist. Nonverbal learning and memory are strengths relative to verbal skills. Expressive language is delayed relative to comprehension. Aspects of language skills continue to develop throughout adolescence, although language skills remain compromised in adulthood. Deficits in attention/executive functions are present in childhood and become more pronounced with age. Characteristic features associated with DS (cheerful, social nature) are personality assets. Children are at a lower risk for psychopathology compared to other children with ID; families report lower levels of stress and a more positive outlook. In youth, externalizing behaviors may be problematic, whereas a shift toward internalizing behaviors emerges with maturity. Changes in emotional/behavioral functioning in adulthood are typically associated with neurodegeneration and individuals with DS are higher risk for dementia of the Alzheimer's type. Individuals with DS possess many unique strengths and weaknesses that should be appreciated as they develop across the lifespan. Awareness of this profile by professionals and caregivers can promote early detection and support cognitive and behavioral development. © 2015 Wiley Periodicals, Inc.

Homo sapiens-Specific Binding Site Variants within Brain Exclusive Enhancers Are Subject to Accelerated Divergence across Human Population.

PubMed

Zehra, Rabail; Abbasi, Amir Ali

2018-03-01

Empirical assessments of human accelerated noncoding DNA frgaments have delineated presence of many cis-regulatory elements. Enhancers make up an important category of such accelerated cis-regulatory elements that efficiently control the spatiotemporal expression of many developmental genes. Establishing plausible reasons for accelerated enhancer sequence divergence in Homo sapiens has been termed significant in various previously published studies. This acceleration by including closely related primates and archaic human data has the potential to open up evolutionary avenues for deducing present-day brain structure. This study relied on empirically confirmed brain exclusive enhancers to avoid any misjudgments about their regulatory status and categorized among them a subset of enhancers with an exceptionally accelerated rate of lineage specific divergence in humans. In this assorted set, 13 distinct transcription factor binding sites were located that possessed unique existence in humans. Three of 13 such sites belonging to transcription factors SOX2, RUNX1/3, and FOS/JUND possessed single nucleotide variants that made them unique to H. sapiens upon comparisons with Neandertal and Denisovan orthologous sequences. These variants modifying the binding sites in modern human lineage were further substantiated as single nucleotide polymorphisms via exploiting 1000 Genomes Project Phase3 data. Long range haplotype based tests laid out evidence of positive selection to be governing in African population on two of the modern human motif modifying alleles with strongest results for SOX2 binding site. In sum, our study acknowledges acceleration in noncoding regulatory landscape of the genome and highlights functional parts within it to have undergone accelerated divergence in present-day human population.

On-Demand Dissolution of Chemically Cross-Linked Hydrogels.

PubMed

Konieczynska, Marlena D; Grinstaff, Mark W

2017-02-21

The formation and subsequent on-demand dissolution of chemically cross-linked hydrogels is of keen interest to chemists, engineers, and clinicians. In this Account, we summarize our recent advances in the area of dissolvable chemically cross-linked hydrogels and provide a comparative discussion of other recent hydrogel systems. Using biocompatible macromonomers, we developed a library of cross-linked dendritic hydrogels that possess favorable properties, including biocompatibility, tissue adhesion, and swelling. Additionally, these hydrogels possess the unique ability to dissolve on-demand via application of a biocompatible aqueous solution. Each of the three hydrogel systems described employs a thiol-thioester exchange reaction as the mechanism of dissolution. These new materials successfully decrease bleeding in in vivo models of hepatic and aortic hemorrhage and dissolve on-demand, providing easy removal. In addition, we evaluated these hydrogels as dressings for second-degree burn wounds and performed proof-of-concept in vivo studies. These hydrogel wound dressings provide a means of repeatedly changing the dressing in a minimally invasive and atraumatic manner while also serving as a protective barrier against bacterial infection. Finally, we highlight the seminal work of other researchers in the field of dissolvable chemically cross-linked hydrogels using thiol-disulfide exchange, retro-Michael-type, and retro-Diels-Alder reactions. These chemistries provide a versatile synthetic toolbox to dissolve hydrogels in a controlled manner on time scales from minutes to weeks. Continued investigation of these dissolution approaches as well as the development of new chemical reactions will open doors to other avenues of on-demand dissolution and expand the application space for these materials. In summary, the management and closure of wounds after traumatic injury or surgical intervention are of significant clinical importance. Stimuli-responsive hydrogels that function as sealants, adhesives, or dressings are emerging as vital alternatives to current standards of care that rely upon conventional sutures, staples, or dressings.

Transport genes and chemotaxis in Laribacter hongkongensis: a genome-wide analysis

PubMed Central

2011-01-01

Background Laribacter hongkongensis is a Gram-negative, sea gull-shaped rod associated with community-acquired gastroenteritis. The bacterium has been found in diverse freshwater environments including fish, frogs and drinking water reservoirs. Using the complete genome sequence data of L. hongkongensis, we performed a comprehensive analysis of putative transport-related genes and genes related to chemotaxis, motility and quorum sensing, which may help the bacterium adapt to the changing environments and combat harmful substances. Results A genome-wide analysis using Transport Classification Database TCDB, similarity and keyword searches revealed the presence of a large diversity of transporters (n = 457) and genes related to chemotaxis (n = 52) and flagellar biosynthesis (n = 40) in the L. hongkongensis genome. The transporters included those from all seven major transporter categories, which may allow the uptake of essential nutrients or ions, and extrusion of metabolic end products and hazardous substances. L. hongkongensis is unique among closely related members of Neisseriaceae family in possessing higher number of proteins related to transport of ammonium, urea and dicarboxylate, which may reflect the importance of nitrogen and dicarboxylate metabolism in this assacharolytic bacterium. Structural modeling of two C4-dicarboxylate transporters showed that they possessed similar structures to the determined structures of other DctP-TRAP transporters, with one having an unusual disulfide bond. Diverse mechanisms for iron transport, including hemin transporters for iron acquisition from host proteins, were also identified. In addition to the chemotaxis and flagella-related genes, the L. hongkongensis genome also contained two copies of qseB/qseC homologues of the AI-3 quorum sensing system. Conclusions The large number of diverse transporters and genes involved in chemotaxis, motility and quorum sensing suggested that the bacterium may utilize a complex system to adapt to different environments. Structural modeling will provide useful insights on the transporters in L. hongkongensis. PMID:21849034

Rotifers from selected inland saline waters in the Chihuahuan Desert of México

PubMed Central

Walsh, Elizabeth J; Schröder, Thomas; Wallace, Robert L; Ríos-Arana, Judith V; Rico-Martínez, Roberto

2008-01-01

Background In spite of considerable efforts over past decades we still know relatively little regarding the biogeography of rotifers of inland waters in México. To help rectify this we undertook an extensive survey of the rotifer fauna of 48 water bodies in the Chihuahuan Desert of México. Results Of the sites surveyed, 21 had salinities ≥ 2000 μS cm-1 and in these we found 57 species of monogonont rotifers and several bdelloids. Species richness in the saline sites varied widely, with a range in species richness of 1 to 27 and a mean (± 1SD) = 8.8 (± 6.2). Collectively all sites possess relatively high percent single- and doubletons, 33.3 and 21.7%, respectively. Simpson's Asymmetric Index indicated that similarity in rotifer species composition varied widely among a set of 10 sites. These were selected because they were sampled more frequently or represent unusual habitats. These SAI values ranged from 0.00 (complete dissimilarity) to 1.00 (complete similarity). The Jaccard Index varied between 0.00 and 0.35. This observation probably reflects similarities and differences in water chemistry among these sites. Inland saline systems differed in their chemical composition by region. Conductivity was related to hardness and alkalinity. In addition, hardness was positively associated with chloride and sulfate. RDA showed that several species were positively associated with chloride concentration. Other factors that were significantly associated with rotifer species included the presence of macrophytes, nitrate content, oxygen concentration, TDS, latitude and whether the habitat was a large lake or reservoir. Conclusion This study illustrates the diversity of the rotiferan fauna of inland saline systems and the uniqueness among waterbodies. Conservation of these systems is needed to preserve these unique sources of biodiversity that include rotifers and the other endemic species found in association with them. PMID:18533042

Analysis of the Legionella longbeachae Genome and Transcriptome Uncovers Unique Strategies to Cause Legionnaires' Disease

PubMed Central

Rusniok, Christophe; Lomma, Mariella; Dervins-Ravault, Delphine; Newton, Hayley J.; Sansom, Fiona M.; Jarraud, Sophie; Zidane, Nora; Ma, Laurence; Bouchier, Christiane; Etienne, Jerôme; Hartland, Elizabeth L.; Buchrieser, Carmen

2010-01-01

Legionella pneumophila and L. longbeachae are two species of a large genus of bacteria that are ubiquitous in nature. L. pneumophila is mainly found in natural and artificial water circuits while L. longbeachae is mainly present in soil. Under the appropriate conditions both species are human pathogens, capable of causing a severe form of pneumonia termed Legionnaires' disease. Here we report the sequencing and analysis of four L. longbeachae genomes, one complete genome sequence of L. longbeachae strain NSW150 serogroup (Sg) 1, and three draft genome sequences another belonging to Sg1 and two to Sg2. The genome organization and gene content of the four L. longbeachae genomes are highly conserved, indicating strong pressure for niche adaptation. Analysis and comparison of L. longbeachae strain NSW150 with L. pneumophila revealed common but also unexpected features specific to this pathogen. The interaction with host cells shows distinct features from L. pneumophila, as L. longbeachae possesses a unique repertoire of putative Dot/Icm type IV secretion system substrates, eukaryotic-like and eukaryotic domain proteins, and encodes additional secretion systems. However, analysis of the ability of a dotA mutant of L. longbeachae NSW150 to replicate in the Acanthamoeba castellanii and in a mouse lung infection model showed that the Dot/Icm type IV secretion system is also essential for the virulence of L. longbeachae. In contrast to L. pneumophila, L. longbeachae does not encode flagella, thereby providing a possible explanation for differences in mouse susceptibility to infection between the two pathogens. Furthermore, transcriptome analysis revealed that L. longbeachae has a less pronounced biphasic life cycle as compared to L. pneumophila, and genome analysis and electron microscopy suggested that L. longbeachae is encapsulated. These species-specific differences may account for the different environmental niches and disease epidemiology of these two Legionella species. PMID:20174605

Brain anatomy in Diplura (Hexapoda)

PubMed Central

2012-01-01

Background In the past decade neuroanatomy has proved to be a valuable source of character systems that provide insights into arthropod relationships. Since the most detailed description of dipluran brain anatomy dates back to Hanström (1940) we re-investigated the brains of Campodea augens and Catajapyx aquilonaris with modern neuroanatomical techniques. The analyses are based on antibody staining and 3D reconstruction of the major neuropils and tracts from semi-thin section series. Results Remarkable features of the investigated dipluran brains are a large central body, which is organized in nine columns and three layers, and well developed mushroom bodies with calyces receiving input from spheroidal olfactory glomeruli in the deutocerebrum. Antibody staining against a catalytic subunit of protein kinase A (DC0) was used to further characterize the mushroom bodies. The japygid Catajapyx aquilonaris possesses mushroom bodies which are connected across the midline, a unique condition within hexapods. Conclusions Mushroom body and central body structure shows a high correspondence between japygids and campodeids. Some unique features indicate that neuroanatomy further supports the monophyly of Diplura. In a broader phylogenetic context, however, the polarization of brain characters becomes ambiguous. The mushroom bodies and the central body of Diplura in several aspects resemble those of Dicondylia, suggesting homology. In contrast, Archaeognatha completely lack mushroom bodies and exhibit a central body organization reminiscent of certain malacostracan crustaceans. Several hypotheses of brain evolution at the base of the hexapod tree are discussed. PMID:23050723

Music and the Meeting of Human Minds.

PubMed

Harvey, Alan R

2018-01-01

Over tens of thousands of years of human genetic and cultural evolution, many types and varieties of music and language have emerged; however, the fundamental components of each of these modes of communication seem to be common to all human cultures and social groups. In this brief review, rather than focusing on the development of different musical techniques and practices over time, the main issues addressed here concern: (i) when, and speculations as to why, modern Homo sapiens evolved musical behaviors, (ii) the evolutionary relationship between music and language, and (iii) why humans, perhaps unique among all living species, universally continue to possess two complementary but distinct communication streams. Did music exist before language, or vice versa, or was there a common precursor that in some way separated into two distinct yet still overlapping systems when cognitively modern H. sapiens evolved? A number of theories put forward to explain the origin and persistent universality of music are considered, but emphasis is given, supported by recent neuroimaging, physiological, and psychological findings, to the role that music can play in promoting trust, altruistic behavior, social bonding, and cooperation within groups of culturally compatible but not necessarily genetically related humans. It is argued that, early in our history, the unique socializing and harmonizing power of music acted as an essential counterweight to the new and evolving sense of self, to an emerging sense of individuality and mortality that was linked to the development of an advanced cognitive capacity and articulate language capability.

A pressure relaxation closure model for one-dimensional, two-material Lagrangian hydrodynamics based on the Riemann problem

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

Kamm, James R; Shashkov, Mikhail J

2009-01-01

Despite decades of development, Lagrangian hydrodynamics of strengthfree materials presents numerous open issues, even in one dimension. We focus on the problem of closing a system of equations for a two-material cell under the assumption of a single velocity model. There are several existing models and approaches, each possessing different levels of fidelity to the underlying physics and each exhibiting unique features in the computed solutions. We consider the case in which the change in heat in the constituent materials in the mixed cell is assumed equal. An instantaneous pressure equilibration model for a mixed cell can be cast asmore » four equations in four unknowns, comprised of the updated values of the specific internal energy and the specific volume for each of the two materials in the mixed cell. The unique contribution of our approach is a physics-inspired, geometry-based model in which the updated values of the sub-cell, relaxing-toward-equilibrium constituent pressures are related to a local Riemann problem through an optimization principle. This approach couples the modeling problem of assigning sub-cell pressures to the physics associated with the local, dynamic evolution. We package our approach in the framework of a standard predictor-corrector time integration scheme. We evaluate our model using idealized, two material problems using either ideal-gas or stiffened-gas equations of state and compare these results to those computed with the method of Tipton and with corresponding pure-material calculations.« less

Sensorimotor responsiveness and resolution in the giraffe.

PubMed

More, Heather L; O'Connor, Shawn M; Brøndum, Emil; Wang, Tobias; Bertelsen, Mads F; Grøndahl, Carsten; Kastberg, Karin; Hørlyck, Arne; Funder, Jonas; Donelan, J Maxwell

2013-03-15

The ability of an animal to detect and respond to changes in the environment is crucial to its survival. However, two elements of sensorimotor control - the time required to respond to a stimulus (responsiveness) and the precision of stimulus detection and response production (resolution) - are inherently limited by a competition for space in peripheral nerves and muscles. These limitations only become more acute as animal size increases. In this paper, we investigated whether the physiology of giraffes has found unique solutions for maintaining sensorimotor performance in order to compensate for their extreme size. To examine responsiveness, we quantified three major sources of delay: nerve conduction delay, muscle electromechanical delay and force generation delay. To examine resolution, we quantified the number and size distribution of nerve fibers in the sciatic nerve. Rather than possessing a particularly unique sensorimotor system, we found that our measurements in giraffes were broadly comparable to size-dependent trends seen across other terrestrial mammals. Consequently, both giraffes and other large animals must contend with greater sensorimotor delays and lower innervation density in comparison to smaller animals. Because of their unconventional leg length, giraffes may experience even longer delays compared with other animals of the same mass when sensing distal stimuli. While there are certainly advantages to being tall, there appear to be challenges as well - our results suggest that giraffes are less able to precisely and accurately sense and respond to stimuli using feedback alone, particularly when moving quickly.

36 CFR 13.908 - Fishing limit of catch and in possession.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Fishing limit of catch and in possession. 13.908 Section 13.908 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and...

36 CFR 13.908 - Fishing limit of catch and in possession.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Fishing limit of catch and in possession. 13.908 Section 13.908 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and...

36 CFR 13.908 - Fishing limit of catch and in possession.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Fishing limit of catch and in possession. 13.908 Section 13.908 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Denali National Park and...

Carbon nanotubes from synthesis to in vivo biomedical applications.

PubMed

Sajid, Muhammad Imran; Jamshaid, Usama; Jamshaid, Talha; Zafar, Nadiah; Fessi, H; Elaissari, Abdelhamid

2016-03-30

Owing to their unique and interesting properties, extensive research round the globe has been carried out on carbon nanotubes and carbon nanotubes based systems to investigate their practical usefulness in biomedical applications. The results from these studies demonstrate a great promise in their use in targeted drug delivery systems, diagnostic techniques and in bio-analytical applications. Although, carbon nanotubes possess quite interesting properties, which make them potential candidates in the biomedical science, but they also have some inherent properties which arise great concern regarding their biosafety. In this comprehensive review, we have discussed different aspects of carbon nanotubes and carbon nanotube based systems related to biomedical applications. In the beginning, a short historical account of these tiny yet powerful particles is given followed by discussion regarding their types, properties, methods of synthesis, large scale production method, purification techniques and characterization aspects of carbon nanotubes. In the second part of the review, the functionalization of carbon nanotubes is reviewed in detail, which is not only important to make them biocompatible and stable in biological systems but also render them a great property of loading various biomolecules, diagnostic and therapeutic moieties resulting in diversified applications. In the final part of the review, emphasis is given on the pharmacokinetic aspects of carbon nanotubes including administration routes, absorption mechanisms, distribution and elimination of carbon nanotubes based systems. Lastly, a comprehensive account about the potential biomedical applications has been given followed by insights into the future. Copyright © 2016 Elsevier B.V. All rights reserved.