High Data Rate Architecture (HiDRA)

Science.gov (United States)

Hylton, Alan; Raible, Daniel

2016-01-01

high-rate laser terminals. These must interface with the existing, aging data infrastructure. The High Data Rate Architecture (HiDRA) project is designed to provide networked store, carry, and forward capability to optimize data flow through both the existing radio frequency (RF) and new laser communications terminal. The networking capability is realized through the Delay Tolerant Networking (DTN) protocol, and is used for scheduling data movement as well as optimizing the performance of existing RF channels. HiDRA is realized as a distributed FPGA memory and interface controller that is itself controlled by a local computer running DTN software. Thus HiDRA is applicable to other arenas seeking to employ next-generation communications technologies, e.g. deep space. In this paper, we describe HiDRA and its far-reaching research implications.

Ultrastrong Bioinspired Graphene-Based Fibers via Synergistic Toughening.

Science.gov (United States)

Zhang, Yuanyuan; Li, Yuchen; Ming, Peng; Zhang, Qi; Liu, Tianxi; Jiang, Lei; Cheng, Qunfeng

2016-04-13

Ultrastrong bioinspired graphene-based fibers are designed and prepared via synergistic toughening of ionic and covalent bonding. The tensile strength reaches up to 842.6 MPa and is superior to all other reported graphene-based fibers. In addition, its electrical conductivity is as high as 292.4 S cm(-1). This bioinspired synergistic toughening strategy supplies new insight toward the construction of integrated high-performance graphene-based fibers in the near future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Medical dictionary MedDRA: Used in over 60 countries, among which is Montenegro

Directory of Open Access Journals (Sweden)

Mugoša Snežana S.

2015-01-01

Full Text Available Introduction: Medical Dictionary for Regulatory Activities (MedDRA is a medical coding dictionary which is designed in order to be used by regulatory authorities, pharmaceutical companies, clinical research organizations and health care professionals, i.e. all participants in the system of medicines safety monitoring. Methods: This article describes process which is used for medical coding in clinical data management and, in brief, most commonly used medical dictionary MedDRA. The purpose of this paper is a modest contribution to easier and more successful understanding of the encoding process in clinical data management in the field of pharmacovigilance. Topic: MedDRA Development, structure, multi-axiality, availability of foreign languages, as well as common problems faced by medical coding expert while coding were presented. Conclusion: MedDRA has become the standard medical terminology for drug regulators and pharmaceutical companies in Montenegro. Training should be provided to all coders in order to achieve the optimum level of coding and to ensure that all the parameters for quality are achieved. Coding should be treated as one of the most important function in clinical research.

ELA-DRA polymorphisms are not associated with Equine Arteritis Virus infection in horses from Argentina.

Science.gov (United States)

Kalemkerian, P B; Metz, G E; Peral-Garcia, P; Echeverria, M G; Giovambattista, G; Díaz, S

2012-12-01

Polymorphisms at Major Histocompatibility Complex (MHC) genes have been associated with resistance/susceptibility to infectious diseases in domestic animals. The aim of this investigation was to evaluate whether polymorphisms of the DRA gene the Equine Lymphocyte Antigen is associated with susceptibility to Equine Arteritis Virus (EAV) infection in horses in Argentina. The equine DRA gene was screened for polymorphisms using Pyrosequencing® Technology which allowed the detection of three ELA-DRA exon 2 alleles. Neither allele frequencies nor genotypic differentiation exhibited any statistically significant (P-values=0.788 and 0.745) differences between the EAV-infected and no-infected horses. Fisher's exact test and OR calculations did not show any significant association. As a consequence, no association could be established between the serological condition and ELA-DRA. Copyright © 2012 Elsevier Ltd. All rights reserved.

pH-dependent structural change of the extracellular sensor domain of the DraK histidine kinase from Streptomyces coelicolor

International Nuclear Information System (INIS)

Yeo, Kwon Joo; Kim, Eun Hye; Hwang, Eunha; Han, Young-Hyun; Eo, Yumi; Kim, Hyun Jung; Kwon, Ohsuk; Hong, Young-Soo; Cheong, Chaejoon; Cheong, Hae-Kap

2013-01-01

Highlights: ► We described the biochemical and biophysical properties of the extracellular sensory domain (ESD) of DraK histidine kinase. ► The ESD of DraK showed a reversible pH-dependent conformational change in a wide pH range. ► The E83 is an important residue for the pH-dependent conformational change. -- Abstract: Recently, the DraR/DraK (Sco3063/Sco3062) two-component system (TCS) of Streptomycescoelicolor has been reported to be involved in the differential regulation of antibiotic biosynthesis. However, it has not been shown that under which conditions and how the DraR/DraK TCS is activated to initiate the signal transduction process. Therefore, to understand the sensing mechanism, structural study of the sensory domain of DraK is highly required. Here, we report the biochemical and biophysical properties of the extracellular sensory domain (ESD) of DraK. We observed a reversible pH-dependent conformational change of the ESD in a pH range of 2.5–10. Size-exclusion chromatography and AUC (analytical ultracentrifugation) data indicated that the ESD is predominantly monomeric in solution and exists in equilibrium between monomer and dimer states in acidic condition. Using NMR (nuclear magnetic resonance) and CD (circular dichroism) spectroscopy, our findings suggest that the structure of the ESD at low pH is more structured than that at high pH. In particular, the glutamate at position 83 is an important residue for the pH-dependent conformational change. These results suggest that this pH-dependent conformational change of ESD may be involved in signal transduction process of DraR/DraK TCS

pH-dependent structural change of the extracellular sensor domain of the DraK histidine kinase from Streptomyces coelicolor

Energy Technology Data Exchange (ETDEWEB)

Yeo, Kwon Joo [Division of Magnetic Resonance, Korea Basic Science Institute (KBSI), 16 Yeongudanji-Ro, Ochang, Chungbuk 363-883 (Korea, Republic of); Kim, Eun Hye [Systems and Synthetic Biology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-Ro, Yuseong-Gu, Daejeon 305-333 (Korea, Republic of); Hwang, Eunha; Han, Young-Hyun; Eo, Yumi; Kim, Hyun Jung [Division of Magnetic Resonance, Korea Basic Science Institute (KBSI), 16 Yeongudanji-Ro, Ochang, Chungbuk 363-883 (Korea, Republic of); Kwon, Ohsuk [Systems and Synthetic Biology Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), 125 Gwahak-Ro, Yuseong-Gu, Daejeon 305-333 (Korea, Republic of); Hong, Young-Soo [Chemical Biology Research Center, KRIBB, 30 Yeongudanji-Ro, Ochang, Chungbuk 363-883 (Korea, Republic of); Cheong, Chaejoon, E-mail: cheong@kbsi.re.kr [Division of Magnetic Resonance, Korea Basic Science Institute (KBSI), 16 Yeongudanji-Ro, Ochang, Chungbuk 363-883 (Korea, Republic of); Cheong, Hae-Kap, E-mail: haekap@kbsi.re.kr [Division of Magnetic Resonance, Korea Basic Science Institute (KBSI), 16 Yeongudanji-Ro, Ochang, Chungbuk 363-883 (Korea, Republic of)

2013-02-15

Highlights: ► We described the biochemical and biophysical properties of the extracellular sensory domain (ESD) of DraK histidine kinase. ► The ESD of DraK showed a reversible pH-dependent conformational change in a wide pH range. ► The E83 is an important residue for the pH-dependent conformational change. -- Abstract: Recently, the DraR/DraK (Sco3063/Sco3062) two-component system (TCS) of Streptomycescoelicolor has been reported to be involved in the differential regulation of antibiotic biosynthesis. However, it has not been shown that under which conditions and how the DraR/DraK TCS is activated to initiate the signal transduction process. Therefore, to understand the sensing mechanism, structural study of the sensory domain of DraK is highly required. Here, we report the biochemical and biophysical properties of the extracellular sensory domain (ESD) of DraK. We observed a reversible pH-dependent conformational change of the ESD in a pH range of 2.5–10. Size-exclusion chromatography and AUC (analytical ultracentrifugation) data indicated that the ESD is predominantly monomeric in solution and exists in equilibrium between monomer and dimer states in acidic condition. Using NMR (nuclear magnetic resonance) and CD (circular dichroism) spectroscopy, our findings suggest that the structure of the ESD at low pH is more structured than that at high pH. In particular, the glutamate at position 83 is an important residue for the pH-dependent conformational change. These results suggest that this pH-dependent conformational change of ESD may be involved in signal transduction process of DraR/DraK TCS.

Revista Espinhaço entrevistaDra. Bette Otto Bliesner(NCAR Boulder

Directory of Open Access Journals (Sweden)

Kourosh Behzadian

2016-12-01

Full Text Available Dra. Bette Otto Bliesner foi entrevistada pela Revista Espinhaço durante o BIARI 2016, que ocorreu em Providence (EUA na Brown University. Para este volume especial da Revista Espihaço, a Dra. Bette, pesquisadora do National Center for Atmospheric Research (NCAR e especialista em modelagem climática e paleo-climatologia, traz reflexões sobre seu recente trabalho no IPCC.Esta entrevista foi conduzida por Kourosh Behzadian (University of West London, Douglas Sathler (FIH/Cegeo/UFVJM and Lorena Fleury (UFRGS.

Revised photometric elements of the eclipsing binary TW Dra

International Nuclear Information System (INIS)

Giuricin, G.; Mardirossian, F.; Predolin, F.

1980-01-01

The photoelectric light curves of TW Dra obtained by Baglow (1952) and by Waltser (1978) have been re-analysed by means of Wood's (1972) model in order to obtain accurate photometric elements. Significantly different elements have resulted from the two sets of observations, but more confidence can be given to the elements deduced from Walter's (1978) data. Radii and luminosities have been computed with the aid of Popper's (1978) new values for masses. TW Dra is confirmed to be a typical sd-system, having a distrinctly oversized and overluminous secondary. Interestingly, the primary appears to be slightly more luminous than expected for a Main-Sequences star, in agreement with theoretical predictions for present primaries of mass-exchange binaries systems. (orig.)

pH-dependent structural change of the extracellular sensor domain of the DraK histidine kinase from Streptomyces coelicolor.

Science.gov (United States)

Yeo, Kwon Joo; Kim, Eun Hye; Hwang, Eunha; Han, Young-Hyun; Eo, Yumi; Kim, Hyun Jung; Kwon, Ohsuk; Hong, Young-Soo; Cheong, Chaejoon; Cheong, Hae-Kap

2013-02-15

Recently, the DraR/DraK (Sco3063/Sco3062) two-component system (TCS) of Streptomycescoelicolor has been reported to be involved in the differential regulation of antibiotic biosynthesis. However, it has not been shown that under which conditions and how the DraR/DraK TCS is activated to initiate the signal transduction process. Therefore, to understand the sensing mechanism, structural study of the sensory domain of DraK is highly required. Here, we report the biochemical and biophysical properties of the extracellular sensory domain (ESD) of DraK. We observed a reversible pH-dependent conformational change of the ESD in a pH range of 2.5-10. Size-exclusion chromatography and AUC (analytical ultracentrifugation) data indicated that the ESD is predominantly monomeric in solution and exists in equilibrium between monomer and dimer states in acidic condition. Using NMR (nuclear magnetic resonance) and CD (circular dichroism) spectroscopy, our findings suggest that the structure of the ESD at low pH is more structured than that at high pH. In particular, the glutamate at position 83 is an important residue for the pH-dependent conformational change. These results suggest that this pH-dependent conformational change of ESD may be involved in signal transduction process of DraR/DraK TCS. Copyright © 2013 Elsevier Inc. All rights reserved.

The fourth outburst during the present active stage of symbiotic binary AG Dra

Science.gov (United States)

Galis, R.; Merc, J.; Vrastak, M.; Teyssier, F.; Lester, T.; Boyd, D.; Sims, W.; Leedjarv, L.

2018-04-01

The symbiotic system AG Dra regularly undergoes quiescent and active stages which consist of several outbursts repeating at about 360d interval (Galis et al. 2017, OEJV 180, 24). After seven years of flat quiescence following the 2006-08 major outbursts, in the late spring of 2015, AG Dra began rising again in brightness toward what appeared to be a new minor outburst (ATel #7582).

On the Development and Application of High Data Rate Architecture (HiDRA) in Future Space Networks

Science.gov (United States)

Hylton, Alan; Raible, Daniel; Clark, Gilbert

2017-01-01

Historically, space missions have been severely constrained by their ability to downlink the data they have collected. These constraints are a result of relatively low link rates on the spacecraft as well as limitations on the time during which data can be sent. As part of a coherent strategy to address existing limitations and get more data to the ground more quickly, the Space Communications and Navigation (SCaN) program has been developing an architecture for a future solar system Internet. The High Data Rate Architecture (HiDRA) project is designed to fit into such a future SCaN network. HiDRA's goal is to describe a general packet-based networking capability which can be used to provide assets with efficient networking capabilities while simultaneously reducing the capital costs and operational costs of developing and flying future space systems.Along these lines, this paper begins by reviewing various characteristics of modern satellite design as well as relevant characteristics of emerging technologies (such as free-space optical links capable of working at 100+ Gbps). Next, the paper describes HiDRA's design, and how the system is able to both integrate and support the operation of not only today's high-rate systems, but also the high-rate systems likely to be found in the future. This section also explores both existing and future networking technologies, such as Delay Tolerant Networking (DTN) protocol (RFC4838 citeRFC:1, RFC5050citeRFC:2), and explains how HiDRA supports them. Additionally, this section explores how HiDRA is used for scheduling data movement through both proactive and reactive link management. After this, the paper moves on to explore a reference implementation of HiDRA. This implementation is currently being realized based on a Field Programmable Gate Array (FPGA) memory and interface controller that is itself controlled by a local computer running DTN software. Next, this paper explores HiDRA's natural evolution, which includes an

Methods and pitfalls in searching drug safety databases utilising the Medical Dictionary for Regulatory Activities (MedDRA).

Science.gov (United States)

Brown, Elliot G

2003-01-01

The Medical Dictionary for Regulatory Activities (MedDRA) is a unified standard terminology for recording and reporting adverse drug event data. Its introduction is widely seen as a significant improvement on the previous situation, where a multitude of terminologies of widely varying scope and quality were in use. However, there are some complexities that may cause difficulties, and these will form the focus for this paper. Two methods of searching MedDRA-coded databases are described: searching based on term selection from all of MedDRA and searching based on terms in the safety database. There are several potential traps for the unwary in safety searches. There may be multiple locations of relevant terms within a system organ class (SOC) and lack of recognition of appropriate group terms; the user may think that group terms are more inclusive than is the case. MedDRA may distribute terms relevant to one medical condition across several primary SOCs. If the database supports the MedDRA model, it is possible to perform multiaxial searching: while this may help find terms that might have been missed, it is still necessary to consider the entire contents of the SOCs to find all relevant terms and there are many instances of incomplete secondary linkages. It is important to adjust for multiaxiality if data are presented using primary and secondary locations. Other sources for errors in searching are non-intuitive placement and the selection of terms as preferred terms (PTs) that may not be widely recognised. Some MedDRA rules could also result in errors in data retrieval if the individual is unaware of these: in particular, the lack of multiaxial linkages for the Investigations SOC, Social circumstances SOC and Surgical and medical procedures SOC and the requirement that a PT may only be present under one High Level Term (HLT) and one High Level Group Term (HLGT) within any single SOC. Special Search Categories (collections of PTs assembled from various SOCs by

Interlayer toughening of fiber composite flywheel rotors

Science.gov (United States)

Groves, Scott E.; Deteresa, Steven J.

1998-01-01

An interlayer toughening mechanism to mitigate the growth of damage in fiber composite flywheel rotors for long application. The interlayer toughening mechanism may comprise one or more tough layers composed of high-elongation fibers, high-strength fibers arranged in a woven pattern at a range from 0.degree. to 90.degree. to the rotor axis and bound by a ductile matrix material which adheres to and is compatible with the materials used for the bulk of the rotor. The number and spacing of the tough interlayers is a function of the design requirements and expected lifetime of the rotor. The mechanism has particular application in uninterruptable power supplies, electrical power grid reservoirs, and compulsators for electric guns, as well as electromechanical batteries for vehicles.

Two-Stage MAS Technique for Analysis of DRA Elements and Arrays on Finite Ground Planes

DEFF Research Database (Denmark)

Larsen, Niels Vesterdal; Breinbjerg, Olav

2007-01-01

A two-stage Method of Auxiliary Sources (MAS) technique is proposed for analysis of dielectric resonator antenna (DRA) elements and arrays on finite ground planes (FGPs). The problem is solved by first analysing the DRA on an infinite ground plane (IGP) and then using this solution to model the FGP...

Glass ceramic toughened with tetragonal zirconia

Science.gov (United States)

Keefer, Keith D.; Michalske, Terry A.

1986-01-01

A phase transformation-toughened glass ceramic and a process for making it are disclosed. A mixture of particulate network-forming oxide, network-modifying oxide, and zirconium oxide is heated to yield a homogeneous melt, and this melt is then heat-treated to precipitate an appreciable quantity of tetragonal zirconia, which is retained at ambient temperature to form a phase transformation-toughened glass ceramic. Nucleating agents and stabilizing agents may be added to the mixture to facilitate processing and improve the ceramic's properties. Preferably, the mixture is first melted at a temperature from 1200.degree. to 1700.degree. C. and is then heat-treated at a temperature within the range of 800.degree. to 1200.degree. C. in order to precipitate tetragonal ZrO.sub.2. The composition, as well as the length and temperature of the heat-treatment, must be carefully controlled to prevent solution of the precipitated tetragonal zirconia and subsequent conversion to the monoclinic phase.

Photometric study of the pulsating, eclipsing binary OO DRA

International Nuclear Information System (INIS)

Zhang, X. B.; Deng, L. C.; Tian, J. F.; Wang, K.; Yan, Z. Z.; Luo, C. Q.; Sun, J. J.; Liu, Q. L.; Xin, H. Q.; Zhou, Q.; Luo, Z. Q.

2014-01-01

We present a comprehensive photometric study of the pulsating, eclipsing binary OO Dra. Simultaneous B- and V-band photometry of the star was carried out on 14 nights. A revised orbital period and a new ephemeris were derived from the data. The first photometric solution of the binary system and the physical parameters of the component stars are determined. They reveal that OO Dra could be a detached system with a less-massive secondary component nearly filling its Roche lobe. By subtracting the eclipsing light changes from the data, we obtained the intrinsic pulsating light curves of the hotter, massive primary component. A frequency analysis of the residual light yields two confident pulsation modes in both B- and V-band data with the dominant frequency detected at 41.865 c/d. A brief discussion concerning the evolutionary status and the pulsation nature of the binary system is finally given.

Feasibility of Using Multilayer Platelets as Toughening Agents

Directory of Open Access Journals (Sweden)

Yuan-Liang Chin

2009-12-01

Full Text Available It is known that the toughness of brittle ceramics can be improved significantly with the addition of hard platelets. In the present study, platelet-shape multilayer ceramic laminates are utilized as a toughening agent for alumina ceramics. They are prepared by laminating the BaTiO3-based ceramic tapes. Although the elastic modulus of the BaTiO3-based platelets is lower than that of the alumina matrix, and the platelets are also reactive to alumina at elevated temperatures, the weak platelets are found to exhibit the ability to deflect major matrix cracks by forming a large number of microcrack branches within the platelets, thus achieving the desired toughening effect.

Interlaminar Toughening of Fiber Reinforced Polymers

Science.gov (United States)

Bian, Dakai

Modification in the resin-rich region between plies, also known as the interlaminar region, was investigated to increase the toughness of laminate composites structures. To achieve suitable modifications, the complexities of the physical and chemical processes during the resin curing procedure must be studied. This includes analyses of the interactions among the co-dependent microstructure, process parameters, and material responses. This dissertation seeks to investigate these interactions via a series of experimental and numerical analyses of the geometric- and temperature-based effects on locally interleaving toughening methods and further interlaminar synergistic toughening without interleaf. Two major weaknesses in composite materials are the brittle resin-rich interlaminar region which forms between the fiber plies after resin infusion, and the ply dropoff region which introduces stress concentration under loads. To address these weaknesses and increase the delamination resistance of the composite specimens, a dual bonding process was explored to alleviate the dropoff effect and toughen the interlaminar region. Hot melt bonding was investigated by applying clamping pressure to ductile thermoplastic interleaf and fiber fabric at an elevated temperature, while diffusion bonding between thermoplastic interleaf and thermoset resin is performed during the resin infusion. This method increased the fracture energy level and thus delamination resistance in the interlaminar region because of deep interleaf penetration into fiber bundles which helped confining crack propagation in the toughened area. The diffusion and precipitation between thermosets and thermoplastics also improved the delamination resistance by forming a semi-interpenetration networks. This phenomenon was investigated in concoctions of low-concentration polystyrene additive modified epoxy system, which facilitates diffusion and precipitation without increasing the viscosity of the system

Proceedings of the Inaugural Pediatric Dermatology Research Alliance (PeDRA) Conference

Science.gov (United States)

Siegel, Dawn H.; Choate, Keith; Drolet, Beth A.; Frieden, Ilona J.; Teng, Joyce M.; Tom, Wynnis; Williams, Mary; Eichenfield, Lawrence F.; Paller, Amy S.

2014-01-01

Abstract/Statement of the problem Skin disease research involving children currently faces several major hurdles and as a result, many therapies are only available for off-label use in children and many of the most pressing clinical needs of our pediatric population remain unsolved. A strategic planning committee of the Society for Pediatric Dermatology (SPD) identified the need for an organized, inclusive research alliance to augment the resources of individual practitioners and pre-existing smaller collaborative groups and facilitate robust, multicenter basic, translational, and clinical research and therapeutic trials. A December 2011 National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) Roundtable on Pediatric Dermatology further detailed the therapeutic gaps and barriers to translation of scientific advances to clinical practice. Building on these forums, in July 2012, a group of interested investigators met in Monterey, CA to develop the infrastructure for collaborative pediatric skin research, now called the Pediatric Dermatology Research Alliance (PeDRA). The vision of PeDRA is to create sustainable collaborative research networks to better understand, prevent, treat and cure dermatologic diseases in children. From that starting point, subcommittees and expert members were added, stakeholders identified, and seed funding garnered, with the first PeDRA stand-alone research meeting* realized in Chicago, IL in October 2013. PMID:25318428

Rigid particle toughening of aliphatic polyketone

NARCIS (Netherlands)

Zuiderduin, W.C.J.; Huetink, Han; Gaymans, R.J.

2006-01-01

The influence of precipitated calcium carbonate particles on the toughening behaviour of aliphatic polyketone has been studied. The calcium carbonate particles had a particle size of 0.7 mm and a stearic acid coating (1%). Composites of 0e31.5 vol% CaCO3 content have been compounded and injection

An implementation of 3D viscoelatic behavior for glass during toughening

DEFF Research Database (Denmark)

Nielsen, Jens Henrik; Olesen, John Forbes; Stang, Henrik

2007-01-01

The paper presents a derivation of an incremental formulation for the thermorheological material behavior of glass during the toughening process. The objective of this paper is to provide a constitutive relationship and a discussion for implementing a 3D thermo-viscoelastic material in a numerica......-Software ABAQUS. It has to be emphasized that other phenomena than stress relaxation are present during the toughening process, however, the purpose of this paper is only to provide a model for the thermo viscoelastic behavior....

Microcracking and mechanical properties of Hafnia-Zirconia toughened alumina composites

International Nuclear Information System (INIS)

Li, H.P.S.; Stevens, R.

1995-01-01

Despite the remarkably similar crystal structures and phase transformations of HfO 2 and ZrO 2 , the tetragonal to monoclinic transformation temperature for HfO 2 takes place six hundred degrees higher than that for ZrO 2 . This suggests the potential for HfO 2 as an engineering material for use at elevated temperatures (>700 C). Alloying HfO 2 with ZrO 2 has been suggested a feasible high-temperature toughening strategy for ZrO 2 -toughened ceramics. The role of ZrO 2 as a second phase toughening agent for ceramic composites has long been recognised and a considerable number of studies reported. In contrast, HfO 2 -toughened ceramics, have not been investigated in detail. This paper gives an account of composite ceramics consisting of an Al 2 O 3 matrix, mixed with unstabilised (Zr-Hf)O 2 inclusions containing volume fractions, of 0, 1, 5, 10, 15, and 25 vol. %, developed to investigate the effects of the second phase content on the microstructure and mechanical properties. A simple cubic packing model of microcracking, based on an ''end-point'' thermodynamic approach, is discussed with respect to microcrack extension for a critical volume fraction of second phase content. The results show an Al 2 O 3 matrix containing 5 vol. % of Hf 0.25 Zr 0.75 O 2 inclusions to give the optimum properties. Using the packing model, the critical volume fraction is predicted at 10 vol. %, which is in a good agreement with experimental results. (orig.)

Effects of coding dictionary on signal generation: a consideration of use of MedDRA compared with WHO-ART.

Science.gov (United States)

Brown, Elliot G

2002-01-01

To support signal generation a terminology should facilitate recognition of medical conditions by using terms which represent unique concepts, providing appropriate, homogeneous grouping of related terms. It should allow intuitive or mathematical identification of adverse events reaching a threshold frequency or with disproportionate incidence, permit identification of important events which are commonly drug-related, and support recognition of new syndromes. It is probable that the Medical Dictionary for Regulatory Activities (MedDRA) preferred terms (PTs) or high level terms (HLTs) will be used to represent adverse events for the purposes of signal generation. A comparison with 315 WHO Adverse Reaction Terminology (WHO-ART) PTs showed that for about 72% of WHO-ART PTs, there were one or two corresponding MedDRA PTs. However, there were instances where there were many MedDRA PTs corresponding to single WHO-ART PTs. In many cases, MedDRA HLTs grouped large numbers of PTs and sometimes there could be problems when a single HLT comprises PTs which represent very different medical concepts, or conditions which differ greatly in their clinical importance. Further studies are needed to compare the way in which identical data sets coded with MedDRA and with other terminologies actually function in generating and exploring signals using the same methods of detection and evaluation.

Zirconia toughened ceramics for heat engine applications

International Nuclear Information System (INIS)

Rossi, G.A.; Blum, J.B.; Manwiller, K.E.; Knapp, C.E.

1986-01-01

Three classes of zirconia toughened ceramics (ZTC) were studied, i.e. Mg-PSZ (MgO-partially stabilized zirconia), Y-TZP (Y/sub 2/O/sub 3/-tetragonal zirconia polycrystals) and ZTA (zirconia toughened alumina). The main objective was to improve the high temperature strength and toughness, which are not satisfactory in the ''state of the art'' ZTC materials. Powders prepared by melting/rapid solidification and by chemical routes were used. The green parts were made by both dry and wet shape forming methods. Fine grained Mg-PSZ ceramics with unique microstructures were produced using the rapidly solidified powders. The Y-TZP materials were improved mainly through microstructure control and by addition of alpha alumina as a dispersed phase. Preliminary results on ZTA ceramics made with the rapidly solidified powders were also obtained. It is concluded that the Al/sub 2/O/sub 3//Y-TZP composites offer a good chance of meeting the program objectives

Intrinsic and extrinsic mortality reunited

DEFF Research Database (Denmark)

Koopman, Jacob J E; Wensink, Maarten J; Rozing, Maarten P

2015-01-01

Intrinsic and extrinsic mortality are often separated in order to understand and measure aging. Intrinsic mortality is assumed to be a result of aging and to increase over age, whereas extrinsic mortality is assumed to be a result of environmental hazards and be constant over age. However......, allegedly intrinsic and extrinsic mortality have an exponentially increasing age pattern in common. Theories of aging assert that a combination of intrinsic and extrinsic stressors underlies the increasing risk of death. Epidemiological and biological data support that the control of intrinsic as well...... as extrinsic stressors can alleviate the aging process. We argue that aging and death can be better explained by the interaction of intrinsic and extrinsic stressors than by classifying mortality itself as being either intrinsic or extrinsic. Recognition of the tight interaction between intrinsic and extrinsic...

Toughening and creep in multiphase intermetallics through ...

Indian Academy of Sciences (India)

It has however often been the case that the process of ductilisation or toughening has also led to a decrease in high temperature properties, especially creep. In this paper we describe approaches to the ductilisation of two different classes of intermetallic alloys through alloying to introduce beneficial, second phase effects.

Intrinsic and extrinsic mortality reunited.

Science.gov (United States)

Koopman, Jacob J E; Wensink, Maarten J; Rozing, Maarten P; van Bodegom, David; Westendorp, Rudi G J

2015-07-01

Intrinsic and extrinsic mortality are often separated in order to understand and measure aging. Intrinsic mortality is assumed to be a result of aging and to increase over age, whereas extrinsic mortality is assumed to be a result of environmental hazards and be constant over age. However, allegedly intrinsic and extrinsic mortality have an exponentially increasing age pattern in common. Theories of aging assert that a combination of intrinsic and extrinsic stressors underlies the increasing risk of death. Epidemiological and biological data support that the control of intrinsic as well as extrinsic stressors can alleviate the aging process. We argue that aging and death can be better explained by the interaction of intrinsic and extrinsic stressors than by classifying mortality itself as being either intrinsic or extrinsic. Recognition of the tight interaction between intrinsic and extrinsic stressors in the causation of aging leads to the recognition that aging is not inevitable, but malleable through the environment. Copyright © 2015 Elsevier Inc. All rights reserved.

Topological Toughening of graphene and other 2D materials

Science.gov (United States)

Gao, Huajian

It has been claimed that graphene, with the elastic modulus of 1TPa and theoretical strength as high as 130 GPa, is the strongest material. However, from an engineering point of view, it is the fracture toughness that determines the actual strength of materials, as crack-like flaws (i.e., cracks, holes, notches, corners, etc.) are inevitable in the design, fabrication, and operation of practical devices and systems. Recently, it has been demonstrated that graphene has very low fracture toughness, in fact close to that of ideally brittle solids. These findings have raised sharp questions and are calling for efforts to explore effective methods to toughen graphene. Recently, we have been exploring the potential use of topological effects to enhance the fracture toughness of graphene. For example, it has been shown that a sinusoidal graphene containing periodically distributed disclination quadrupoles can achieve a mode I fracture toughness nearly twice that of pristine graphene. Here we report working progresses on further studies of topological toughening of graphene and other 2D materials. A phase field crystal method is adopted to generate the atomic coordinates of material with specific topological patterns. We then perform molecular dynamics simulations of fracture in the designed samples, and observe a variety of toughening mechanisms, including crack tip blunting, crack trapping, ligament bridging, crack deflection and daughter crack initiation and coalescence.

Processing and properties of pressable ceramic with non-uniform reinforcement for selective-toughening

Energy Technology Data Exchange (ETDEWEB)

Yi, Wei [School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, WA 6009 (Australia); School of Dentistry, The University of Western Australia, WA 6009 (Australia); Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110004 (China); Hu, Xiaozhi, E-mail: xiao.zhi.hu@uwa.edu.au [School of Mechanical and Chemical Engineering, The University of Western Australia, Perth, WA 6009 (Australia); Ichim, Paul [School of Dentistry, The University of Western Australia, WA 6009 (Australia); Sun, Xudong [Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110004 (China)

2012-12-15

Brittle low-strength and low-toughness pressable dental ceramic can be reinforced by ductile elongated gold-particles (GP). A customized crown structure can be adequately strengthened by distributing GP only in critical sections of the crown, where high tensile stresses are experienced. In the present study, a non-uniformly structured ceramic-matrix composite with excellent interfacial bonding, twofold fracture toughness and strength at desired locations, is fabricated using pressable dental ceramic and GP. The layout pattern and sequence of different GP/ceramic powder mixtures, high-temperature flow properties of these mixtures during hot-pressing and the sample mold geometry are used to control the distribution and locations of GP for selective toughening and strengthening. Nano-crystalline structures of the pressable ceramic-matrix and the nano-scaled interfacial region around GP have been revealed by high-magnification field-emission scanning electron microscopy. Toughening and strengthening mechanisms of the elongated GP including residual stresses from composite processing and ductile fracture of GP are discussed together with SEM observations. Bulk flexural strength and local micro-indentation fracture and deformation characteristics of the selective-toughened ceramic/metal composite have been compared to those of the monolithic pressable ceramic to validate the toughening and strengthening mechanisms.

Processing and properties of pressable ceramic with non-uniform reinforcement for selective-toughening

International Nuclear Information System (INIS)

Yi, Wei; Hu, Xiaozhi; Ichim, Paul; Sun, Xudong

2012-01-01

Brittle low-strength and low-toughness pressable dental ceramic can be reinforced by ductile elongated gold-particles (GP). A customized crown structure can be adequately strengthened by distributing GP only in critical sections of the crown, where high tensile stresses are experienced. In the present study, a non-uniformly structured ceramic–matrix composite with excellent interfacial bonding, twofold fracture toughness and strength at desired locations, is fabricated using pressable dental ceramic and GP. The layout pattern and sequence of different GP/ceramic powder mixtures, high-temperature flow properties of these mixtures during hot-pressing and the sample mold geometry are used to control the distribution and locations of GP for selective toughening and strengthening. Nano-crystalline structures of the pressable ceramic–matrix and the nano-scaled interfacial region around GP have been revealed by high-magnification field-emission scanning electron microscopy. Toughening and strengthening mechanisms of the elongated GP including residual stresses from composite processing and ductile fracture of GP are discussed together with SEM observations. Bulk flexural strength and local micro-indentation fracture and deformation characteristics of the selective-toughened ceramic/metal composite have been compared to those of the monolithic pressable ceramic to validate the toughening and strengthening mechanisms.

Investigation on fracture behavior and mechanisms of DGEBF toughened by CTBN

Science.gov (United States)

Wang, Lulu; Tan, Yefa; Wang, Haitao; Gao, Li; Xiao, Chufan

2018-05-01

Carboxyl-terminated butadiene-co-acrylonitrile (CTBN) was used as the toughener to improve the mechanical performance and fracture toughness of diglycidyl ether of bisphenol F (DGEBF) by prereacted approach. The results show that the chemical bonding interface was formed between DGEBF and CTBN particles in the prepolymerization reaction process, which remarkably enhances the fracture toughness of the composites. Based on the qualitative and quantitative analyses, it shows the main toughening mechanisms are the plastic shear banding effect resulted from the plastic deformation of the EP matrix and the plastic void expansion because of the debonding of CTBN particles from the EP matrix.

Combining Semantic and Lexical Methods for Mapping MedDRA to VCM Icons.

Science.gov (United States)

Lamy, Jean-Baptiste; Tsopra, Rosy

2018-01-01

VCM (Visualization of Concept in Medicine) is an iconic language that represents medical concepts, such as disorders, by icons. VCM has a formal semantics described by an ontology. The icons can be used in medical software for providing a visual summary or enriching texts. However, the use of VCM icons in user interfaces requires to map standard medical terminologies to VCM. Here, we present a method combining semantic and lexical approaches for mapping MedDRA to VCM. The method takes advantage of the hierarchical relations in MedDRA. It also analyzes the groups of lemmas in the term's labels, and relies on a manual mapping of these groups to the concepts in the VCM ontology. We evaluate the method on 50 terms. Finally, we discuss the method and suggest perspectives.

The use of a medical dictionary for regulatory activities terminology (MedDRA) in prescription-event monitoring in Japan (J-PEM).

Science.gov (United States)

Yokotsuka, M; Aoyama, M; Kubota, K

2000-07-01

The Medical Dictionary for Regulatory Activities Terminology (MedDRA) version 2.1 (V2.1) was released in March 1999 accompanied by the MedDRA/J V2.1J specifically for Japanese users. In prescription-event monitoring in Japan (J-PEM), we have employed the MedDRA/J for data entry, signal generation and event listing. In J-PEM, the lowest level terms (LLTs) in the MedDRA/J are used in data entry because the richness of LLTs is judged to be advantageous. A signal is generated normally at the preferred term (PT) level, but it has been found that various reporters describe the same event using descriptions that are potentially encoded by LLTs under different PTs. In addition, some PTs are considered too specific to generate the proper signal. In the system used in J-PEM, when an LLT is selected as a candidate to encode an event, another LLT under a different PT, if any, is displayed on the computer screen so that it may be coded instead of, or in addition to, the candidate LLT. The five-level structure of the MedDRA is used when listing events but some modification is required to generate a functional event list.

Toughening by nano-scaled twin boundaries in nanocrystals

International Nuclear Information System (INIS)

Zhou, Haofei; Qu, Shaoxing; Yang, Wei

2010-01-01

Joint enhancement on strength and toughness provides a cutting-edge research frontier for metals and alloys. Conventional strengthening methods typically lead to suppressed ductility and fracture toughness. In this study, large-scale atomic simulation on the fracture process is performed featuring nanocrystals embedded with nano-scaled twin boundaries (TBs). Four toughening mechanisms by nano-scaled TBs are identified: (i) crack blunting through dislocation accommodation along the nano-scaled TBs; (ii) crack deflection in a manner of intragranular propagation; (iii) daughter crack formation along the nano-scaled TBs that further enhances the toughness and (iv) curved TB planes owing to an excessive pileup of geometrically necessary dislocations. These toughening mechanisms jointly dictate the mechanical behavior of nano-structured materials, and provide insights into the application of nano-scaled TBs with an aim to simultaneously obtain enhanced strength and toughness. New approaches to introduce these coherent internal defects into the nanostructure of crystalline materials are also proposed

Development of ricehusk ash reinforced bismaleimide toughened epoxy nanocomposites

Science.gov (United States)

Kanimozhi, K.; Sethuraman, K.; Selvaraj, V.; Alagar, M.

2014-01-01

Recent past decades have witnessed remarkable advances in composites with potential applications in biomedical devices, aerospace, textiles, civil engineering, energy, electronic engineering, and household products. Thermoset polymer composites have further enhanced and broadened the area of applications of composites. In the present work epoxy-BMI toughened-silica hybrid (RHA/DGEBA-BMI) was prepared using bismaleimide as toughener, bisphenol-A as matrix and a silica precursor derived from rice husk ash as reinforcement with glycidoxypropyltrimethoxysilane as coupling agent. Differential scanning calorimetry, electron microscopy, thermogravimetric analysis, and goniometry were used to characterize RHA/DGEBA-BMI composites developed in the present work. Tensile, impact and flexural strength, tensile and flexural modulus, hardness, dielectric properties were also studied and discussed. The hybrid nanocomposites possess the higher values of the glass transition temperature (Tg) and mechanical properties than those of neat epoxy matrix. PMID:25279372

Diversity of equine major histocompatiblity complex class II DRA locus in Posavina and Croatian Coldblood horse: a new polymorphism detected

Directory of Open Access Journals (Sweden)

Ino Curik

2010-01-01

Full Text Available Domestic equidae display polymorphism within ELA-DRA locus which is not characteristic for other species. We characterised sequence polymorphism present at ELADRA locus exon 2 and estimated allele frequencies in two autochthonous breeds, Posavina and Croatian Coldblood. In 88 horses, four different alleles were found, one of them not reported before in horses. The new allele shows non-synonymous mutation at position 65 (T→A causing amino acid change (Phe→Tyr in antigen binding site and synonymous mutation at position 105 (C→T. Our findings emphasize the importance of DRA polymorphism among equids and some specific DRA frequency pattern potentially specific in draught horses.

Grinding mechanism of zirconia toughened alumina

International Nuclear Information System (INIS)

Tsukuda, A.; Kondo, Y.; Yokota, K.

1998-01-01

In the grinding process, physical properties of ceramics affect both grinding mechanism and quality of ground surface. In this study we focused on fracture toughness of ceramics and the effect on grinding. A grinding test was carried out by single point grinding for ten different zirconia toughened alumina ceramics with different monoclinic zirconia contents. Effects of zirconia contents on the grinding mechanism and crack initiation were discussed. Copyright (1998) AD-TECH - International Foundation for the Advancement of Technology Ltd

The phase stability and toughening effect of 3Y-TZP dispersed in the lanthanum zirconate ceramics

International Nuclear Information System (INIS)

Wang, Yanfei; Xiao, Ping

2014-01-01

The low fracture toughness of lanthanum zirconate (La 2 Zr 2 O 7 , LZ) greatly impedes its wide application as thermal barrier coatings (TBC). The 3 mol% Y 2 O 3 -stabilized tetragonal zirconia polycrystals (3Y-TZP) have been introduced to toughen the brittle LZ ceramics. The dispersive 3Y-TZP undergoes a simultaneous t–m transformation upon cooling below a critical volume fraction x of 3Y-TZP, above which its tetragonal phases can however be preserved. The different stabilities of 3Y-TZP second phases arise from a variation of residual tensile stress within them. The fracture toughness has been greatly improved by dispersing the tetragonal particulates (t-3YSZ) in the LZ matrix and the primary toughening mechanisms are phase transformations of the dispersive second phases and the residual compressive stress within the matrix. An anticipated increase of fracture toughness from the ferroelastic toughening and the residual compressive stress toughening highlights the great potentials to improve coating durability by depositing t′-3YSZ/LZ composite TBCs by the industrial non-equilibrium route

Transient subcritical crack-growth behavior in transformation-toughened ceramics

International Nuclear Information System (INIS)

Dauskardt, R.H.; Ritchie, R.O.; Carter, W.C.; Veirs, D.K.

1990-01-01

Transient subcritical crack-growth behavior following abrupt changes in the applied load are studied in transformation-toughened ceramics. A mechanics analysis is developed to model the transient nature of transformation shielding of the crack tip, K s , with subcritical crack extension following the applied load change. conditions for continued crack growth, crack growth followed by arrest, and no crack growth after the load change, are considered and related to the magnitude and sign of the applied load change and to materials properties such as the critical transformation stress. The analysis is found to provide similar trends in K s compared to values calculated from experimentally measured transformation zones in a transformation-toughened Mg-PSZ. In addition, accurate prediction of the post load-change transient crack-growth behavior is obtained using experimentally derived steady-state subcritical crack-growth relationships for cyclic fatigue in the same material

CT-3DRA registration for radiosurgery treatments: a comparison among rigid, affine and non rigid approaches

International Nuclear Information System (INIS)

Stancanello, J.; Loeckx, D.; Francescon, P.; Calvedon, C.; Avanzo, M.; Cora, S.; Scalchi, P.; Cerveri, P.; Ferrigno, G.

2004-01-01

This work aims at comparing rigid, affine and Local Non Rigid (LNR) CT-3D Rotational Angiography (CT-3DRA) registrations based on mutual information. 10 cranial and 1 spinal cases have been registered by rigid and affine transformations; while LNR has been applied to the cases where residual deformation must be corrected. An example of CT-3DRA registration without regularization term and an example of LNR using the similarity criterion and the regularization term as well as 3D superposition of the 3DRA before and after the registration without the regularization term are presented. All the registrations performed by rigid transformation converged to an acceptable solution. The results about the robustness test in axial direction are reported. Conclusions: For cranial cases, affine transformation endowed with threshold-segmentation pre-processing can be considered the most favourable solution for almost all registrations; for some cases, LNR provides more accurate results. For the spinal case rigid transformation is the most suitable when immobilizing patient during examinations; in this case the increase of accuracy by using LNR registrations seems to be not significant

Validation of a new test for Schistosoma haematobium based on detection of Dra1 DNA fragments in urine: evaluation through latent class analysis.

Directory of Open Access Journals (Sweden)

Olufunmilola Ibironke

2012-01-01

Full Text Available Diagnosis of urogenital schistosomiasis in chronically infected adults is challenging but important, especially because long term infection of the bladder and urinary tract can have dire consequences. We evaluated three tests for viable infection: detection of parasite specific DNA Dra1 fragments, haematuria and presence of parasite eggs for sensitivity (Se and specificity (Sp.Over 400 urine specimens collected from adult volunteers in an endemic area in Western Nigeria were assessed for haematuria then filtered in the field, the filter papers dried and later examined for eggs and DNA. The results were stratified according to sex and age and subjected to Latent Class analysis.Presence of Dra1 in males (Se=100%; Sp=100% exceeded haematuria (Se=87.6%: Sp=34.7% and detection of eggs (Se=70.1%; Sp=100%. In females presence of Dra1 was Se=100%: Sp=100%, exceeding haematuria (Se=86.7%: Sp=77.0% and eggs (Se=70.1%; Sp=100%. Dra1 became undetectable 2 weeks after praziquantel treatment. We conclude detection of Dra1 fragment is a definitive test for the presence of Schistosoma haematobium infection.

Direct observation of toughening mechanisms in carbon nanotube ceramic matrix composites

International Nuclear Information System (INIS)

Xia, Z.; Riester, L.; Curtin, W.A.; Li, H.; Sheldon, B.W.; Liang, J.; Chang, B.; Xu, J.M.

2004-01-01

The excellent mechanical properties of carbon nanotubes (CNTS) are driving research into the creation of new strong, tough nanocomposite systems. Here, the first evidence of toughening mechanisms operating in carbon-nanotube-reinforced ceramic composites is presented. A highly ordered array of parallel multiwall CNTs in an alumina matrix was fabricated. Nanoindentation introduced controlled cracks and the damage was examined by scanning electron microscopy. These nanocomposites exhibit the three hallmarks of toughening found in micron-scale fiber composites: crack deflection at the CNT/matrix interface; crack bridging by CNTs; and CNT pullout on the fracture surfaces. Interface debonding and sliding can thus occur in materials with microstructures approaching the atomic scale. Furthermore, for certain geometries a new mechanism of nanotube collapse in 'shear bands' occurs, rather than crack formation, suggesting that these materials can have multiaxial damage tolerance. The quantitative indentation data and computational models are used to determine the multiwall CNT axial Young's modulus as 200-570 GPa, depending on the nanotube geometry and quality. Three-dimensional FEM analysis indicates that matrix residual stresses on the order of 300 MPa are sustained in these materials without spontaneous cracking, suggesting that residual stress can be used to engineer enhanced performance. These nanoscale ceramic composites thus have potential for toughening and damage tolerance at submicron scales, and so are excellent candidates for wear-resistant coatings

Mechanism of the pH-induced conformational change in the sensor domain of the DraK Histidine kinase via the E83, E105, and E107 residues.

Science.gov (United States)

Yeo, Kwon Joo; Hong, Young-Soo; Jee, Jun-Goo; Lee, Jae Kyoung; Kim, Hyo Jeong; Park, Jin-Wan; Kim, Eun-Hee; Hwang, Eunha; Kim, Sang-Yoon; Lee, Eun-Gyeong; Kwon, Ohsuk; Cheong, Hae-Kap

2014-01-01

The DraR/DraK two-component system was found to be involved in the differential regulation of antibiotic biosynthesis in a medium-dependent manner; however, its function and signaling and sensing mechanisms remain unclear. Here, we describe the solution structure of the extracellular sensor domain of DraK and suggest a mechanism for the pH-dependent conformational change of the protein. The structure contains a mixed alpha-beta fold, adopting a fold similar to the ubiquitous sensor domain of histidine kinase. A biophysical study demonstrates that the E83, E105, and E107 residues have abnormally high pKa values and that they drive the pH-dependent conformational change for the extracellular sensor domain of DraK. We found that a triple mutant (E83L/E105L/E107A) is pH independent and mimics the low pH structure. An in vivo study showed that DraK is essential for the recovery of the pH of Streptomyces coelicolor growth medium after acid shock. Our findings suggest that the DraR/DraK two-component system plays an important role in the pH regulation of S. coelicolor growth medium. This study provides a foundation for the regulation and the production of secondary metabolites in Streptomyces.

Wear mechanisms of toughened zirconias

International Nuclear Information System (INIS)

Becker, P.C.; Libsch, T.A.; Rhee, S.K.

1985-01-01

The dry friction and wear behavior of toughened zirconias against hardened steel was studied using the falex ring and block technique. Three experimental ZrO 2 -Y 2 O 3 ceramics and two commerical ZrO 2 -MgO ceramics were investigated. Each ceramic was tested at 500 and 2000 rpm at normal loads in the range 2.3 to 40.8 kg. Significant trends in the friction and wear data were found correlating composition, test speeds, and loads. Microstructural examination of the ring, ceramic block, and wear debris has shown that the wear process is very complex and incorporates a number of mechanisms

Extrinsic CPT Violation in Neutrino Oscillations

International Nuclear Information System (INIS)

Ohlsson, Tommy

2004-01-01

In this talk, we investigate extrinsic CPT violation in neutrino oscillations in matter with three flavors. Note that extrinsic CPT violation is different from intrinsic CPT violation. Extrinsic CPT violation is one way of quantifying matter effects, whereas intrinsic CPT violation would mean that the CPT invariance theorem is not valid. We present analytical formulas for the extrinsic CPT probability differences and discuss their implications for long-baseline experiments and neutrino factory setups

Dražen Tutić, PhD in Technical Sciences

Directory of Open Access Journals (Sweden)

Miljenko Lapaine

2009-12-01

Full Text Available Dražen Tutić defended his PhD thesis Stereographic and Other Conformal Map Projections  for Croatia at the Faculty of Geodesy of the University of Zagreb on August 4, 2009. The thesis was evaluated by the Committee: Prof. Emeritus Nedjeljko Frančula, Prof. Dr. Miljenko Lapaine (mentor and Prof. Dr. Dušan Petrovič from the Faculty of Civil and Geodetic Engineering of the University of Ljubljana.

Thermally reversible rubber-toughened thermoset networks via Diels-Alder chemistry

NARCIS (Netherlands)

Araya-Hermosilla, R.; Fortunato, G.; Pucci, A.; Raffa, P.; Polgar, L.; Broekhuis, A. A.; Pourhossein, P.; Lima, G. M. R.; Beljaars, M.; Picchioni, F.

In this work we present a reversible and toughened thermoset system based on the covalent incorporation of a furane functionalized ethylene-propylene rubber (EPM-Fu) into a thermoset furane functionalized polyketone (PK-Fu) via Diels-Alder (DA) reversible cross-linking with bismaleimide (b-MA).

Mechanism of the pH-induced conformational change in the sensor domain of the DraK Histidine kinase via the E83, E105, and E107 residues.

Directory of Open Access Journals (Sweden)

Kwon Joo Yeo

Full Text Available The DraR/DraK two-component system was found to be involved in the differential regulation of antibiotic biosynthesis in a medium-dependent manner; however, its function and signaling and sensing mechanisms remain unclear. Here, we describe the solution structure of the extracellular sensor domain of DraK and suggest a mechanism for the pH-dependent conformational change of the protein. The structure contains a mixed alpha-beta fold, adopting a fold similar to the ubiquitous sensor domain of histidine kinase. A biophysical study demonstrates that the E83, E105, and E107 residues have abnormally high pKa values and that they drive the pH-dependent conformational change for the extracellular sensor domain of DraK. We found that a triple mutant (E83L/E105L/E107A is pH independent and mimics the low pH structure. An in vivo study showed that DraK is essential for the recovery of the pH of Streptomyces coelicolor growth medium after acid shock. Our findings suggest that the DraR/DraK two-component system plays an important role in the pH regulation of S. coelicolor growth medium. This study provides a foundation for the regulation and the production of secondary metabolites in Streptomyces.

Carboxyl-terminated butadiene-acrylonitrile-toughened epoxy/carboxyl-modified carbon nanotube nanocomposites: Thermal and mechanical properties

Directory of Open Access Journals (Sweden)

H. F. Xie

2012-09-01

Full Text Available Carboxyl-modified multi-walled carbon nanotubes (MWCNT–COOHs as nanofillers were incorporated into diglycidyl ether of bisphenol A (DGEBA toughened with carboxyl-terminated butadiene-acrylonitrile (CTBN. The carboxyl functional carbon nanotubes were characterized by Fourier-transform infrared spectroscopy and thermogravimetric analysis. Furthermore, cure kinetics, glass transition temperature (Tg, mechanical properties, thermal stability and morphology of DGEBA/CTBN/MWCNT–COOHs nanocomposites were investigated by differential scanning calorimetry (DSC, dynamic mechanical analysis (DMA, universal test machine, thermogravimetric analysis and scanning electron microscopy (SEM. DSC kinetic studies showed that the addition of MWCNT–COOHs accelerated the curing reaction of the rubber-toughened epoxy resin. DMA results revealed that Tg of rubber-toughened epoxy nanocomposites lowered with MWCNT–COOH contents. The tensile strength, elongation at break, flexural strength and flexural modulus of DGEBA/CTBN/MWCNT-COOHs nanocomposites were increased at lower MWCNT-COOH concentration. A homogenous dispersion of nanocomposites at lower MWCNT–COOH concentration was observed by SEM.

Aging and Fracture of Human Cortical Bone and Tooth Dentin

Energy Technology Data Exchange (ETDEWEB)

Ager, Joel; Koester, Kurt J.; Ager III, Joel W.; Ritchie, Robert O.

2008-05-07

Mineralized tissues, such as bone and tooth dentin, serve as structural materials in the human body and, as such, have evolved to resist fracture. In assessing their quantitative fracture resistance or toughness, it is important to distinguish between intrinsic toughening mechanisms which function ahead of the crack tip, such as plasticity in metals, and extrinsic mechanisms which function primarily behind the tip, such as crack bridging in ceramics. Bone and dentin derive their resistance to fracture principally from extrinsic toughening mechanisms which have their origins in the hierarchical microstructure of these mineralized tissues. Experimentally, quantification of these toughening mechanisms requires a crack-growth resistance approach, which can be achieved by measuring the crack-driving force, e.g., the stress intensity, as a function of crack extension ("R-curve approach"). Here this methodology is used to study of the effect of aging on the fracture properties of human cortical bone and human dentin in order to discern the microstructural origins of toughness in these materials.

Development and characterisation of a tungsten-fibre reinforced tungsten composite

International Nuclear Information System (INIS)

Riesch, Johann

2012-01-01

In tungsten-fibre reinforced tungsten, tungsten wire is combined with a tungsten matrix. The outstanding ductility of the fibres and extrinsic mechanisms of energy dissipation lead to an intense toughening. With extensive analytical and experimental investigations a manufacturing method based on chemical vapour infiltration is developed and first material is produced. The toughening mechanisms are shown by means of sophisticated mechanical experiments i.a. X-ray microtomography.

Pressureless sintering of whisker-toughened ceramic composites

Science.gov (United States)

Tiegs, T.N.

1993-05-04

A pressureless sintering method is disclosed for use in the production of whisker-toughened ceramic composites wherein the sintered density of composites containing up to about 20 vol. % SiC whiskers is improved by reducing the average aspect ratio of the whiskers to from about 10 to about 20. Sintering aids further improve the density, permitting the production of composites containing 20 vol. % SiC with sintered densities of 94% or better of theoretical density by a pressureless sintering method.

Toughness determination of zirconia toughened alumina ceramics from growth of indentation-induced cracks

International Nuclear Information System (INIS)

Basu, D.; Sarkar, B.K.

1996-01-01

Short surface cracks were generated by Vickers indentation on the polished surface of alumina and different zirconia toughened alumina (ZTA) specimens, and their morphology was studied by serial sectioning. These cracks were grown in three-point bend tests under stepwise loading, and variation of toughness with crack extension was plotted to graphically separate the contributions from residual stress intensity and applied stress intensity factors. The plateau toughness determined from the intercept height of the crack extension plots exhibited an upward trend with zirconia content up to 15 vol% ZrO 2 addition in the composition, which was proportional to the fraction of transformable tetragonal grains contributing to transformation toughening. copyright 1996 Materials Research Society

Systems design of transformation toughened blast-resistant naval hull steels

Science.gov (United States)

Saha, Arup

A systems approach to computational materials design has demonstrated a new class of ultratough, weldable secondary hardened plate steels combining new levels of strength and toughness while meeting processability requirements. A first prototype alloy has achieved property goals motivated by projected naval hull applications requiring extreme fracture toughness (Cv > 85 ft-lbs (115 J) corresponding to KId > 200 ksi.in1/2 (220 MPa.m1/2)) at strength levels of 150--180 ksi (1034--1241 MPa) yield strength in weldable, formable plate steels. A theoretical design concept was explored integrating the mechanism of precipitated nickel-stabilized dispersed austenite for transformation toughening in an alloy strengthened by combined precipitation of M2C carbides and BCC copper both at an optimal ˜3nm particle size for efficient strengthening. This concept was adapted to plate steel design by employing a mixed bainitic/martensitic matrix microstructure produced by air-cooling after solution-treatment and constraining the composition to low carbon content for weldability. With optimized levels of copper and M2C carbide formers based on a quantitative strength model, a required alloy nickel content of 6.5 wt% was predicted for optimal austenite stability for transformation toughening at the desired strength level of 160 ksi (1100 MPa) yield strength. A relatively high Cu level of 3.65 wt% was employed to allow a carbon limit of 0.05 wt% for good weldability. Hardness and tensile tests conducted on the designed prototype confirmed predicted precipitation strengthening behavior in quench and tempered material. Multi-step tempering conditions were employed to achieve the optimal austenite stability resulting in significant increase of impact toughness to 130 ft-lb (176 J) at a strength level of 160 ksi (1100 MPa). Comparison with the baseline toughness-strength combination determined by isochronal tempering studies indicates a transformation toughening increment of 60% in Charpy

Toughened nanocomposites of polyamide-6 and polyepichlorohydrin elastomer: mechanical and morphological properties

International Nuclear Information System (INIS)

Pinotti, Caio A.; Goncalves, Maria C.; Felisberti, Maria I.

2009-01-01

Blends of polyamide 6, P A6, and polyepichlorohydrin elastomer, PE Pi, nano composites of P A6 and OMMT and toughened nano composites, P A6/PE Pi/OMMT were prepared by twin-screw extrusion. Nanocomposites of P A6 and organophilic clay presented morphology of exfoliated clay with the presence of some tactoids, which were investigated by XRD and TEM. The blends P A6/PE Pi are immiscible with morphology of elastomer disperse phase. The size of the elastomer phase in the PA6 matrix and a better distribution of these phase were achieved with the incorporation of the clay in the ternary nanocomposites. Toughened nano composites presented increases in Young's modulus, Izod impact strength and yield stress, comparing with the blends of P A6 and polyepichlorohydrin elastomer. (author)

Microstructural effects of ductile phase toughening of Nb-Nb silicide composites

International Nuclear Information System (INIS)

Lewandowski, J.J.; Dimiduk, D.; Kerr, W.; Menddiratta, M.G.

1988-01-01

In the Nb-Si system, the terminal Nb phase and Nb 5 Si 3 phase are virtually immiscible up to approximately 2033k. This system offers the potential of producing composites consisting of a ductile refractory metal phase and a strong intermetallic phase. In-situ composites containing different volume fractions of the ductile Nb phase were produced via vacuum arc-casting. Microhardness testing as well as smooth bend bar testing was conducted at temperatures ranging from 298k to 1673k in an attempt to determine microstructural effects on the yield strength and smooth bar fracture strength. Notched bend specimens were similarly tested to determine the effects of the ductile phase (i.e. Nb) on enhancing the notched bend toughness. It is shown that Nb phase often behaves in a ductile manner during testing, thereby toughening the in-situ composite. The mechanism of toughening appears to be due to crack bridging

Enhanced Damage Tolerance High Temperature Composite Using a Biomimetic Toughening System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Lightweight composite structures are required to provide space vehicles with increased thrust-to-weight ratio and durability. New methods for toughening composites...

Isocyanate toughening of pCBT/organoclay nanocomposites with exfoliated structure and enhanced mechanical properties

Directory of Open Access Journals (Sweden)

T. Abt

2014-12-01

Full Text Available Cyclic butylene terephthalate (CBT® is an interesting matrix material for the preparation of nanocomposites due to its very low, water-like melt viscosity which favours clay exfoliation. Nevertheless, polymerized CBT (pCBT is inherently brittle. This paper reports the preparation of isocyanate-toughened nanocomposites made from CBT and organo-modified montmorillonite. The role of the organoclay as reinforcement and the polymeric isocyanate (PMDI as toughening agent on the properties of pCBT was studied. The organoclay increased the stiffness and strength by up to 20% whereas the PMDI improved the deformation behaviour. However, the PMDI did not affect the degree of clay dispersion or exfoliation and flocculated-intercalated structures were observed. The compatibility between the pCBT matrix and clay was further increased by preparing PMDI-tethered intercalated organoclay. The modified organoclay then exfoliated during ring-opening polymerization and yielded true pCBT/clay nanocomposites. This work demonstrates that reactive chain extension of CBT with a polyfunctional isocyanate is an effective method to obtain toughened pCBT nanocomposites. Moreover, isocyanates can enhance the compatibility between pCBT and nanofiller as well as the degree of exfoliation.

Fracture and Toughening of Composites of Polymers and Nanoscale Inorganic and Organic Fillers

National Research Council Canada - National Science Library

Chung, Neal

2001-01-01

The objectives of the project were to investigate the mechanical properties and particularly the fracture mechanisms of a number of nanocomposites, and to discover possible approaches to their toughening...

Preparation of Nano-Scale Biopolymer Extracted from Coconut Residue and Its Performance as Drag Reducing Agent (DRA

Directory of Open Access Journals (Sweden)

Hasan Muhammad Luqman Bin

2017-01-01

Full Text Available Drag or frictional force is defined as force that acts opposite to the object’s relative motion through a fluid which then will cause frictional pressure loss in the pipeline. Drag Reducing Agent (DRA is used to solve this issue and most of the DRAs are synthetic polymers but has some environmental issues. Therefore for this study, biopolymer known as Coconut Residue (CR is selected as the candidate to replace synthetic polymers DRA. The objective of this study is to evaluate the effectiveness of Nano-scale biopolymer DRA on the application of water injection system. Carboxymethyl cellulose (CMC is extracted by synthesizing the cellulose extracted from CR under the alkali-catalyzed reaction using monochloroacetic acid. The synthesize process is held in controlled condition whereby the concentration of NaOH is kept at 60%wt, 60 °C temperature and the reaction time is 4 hours. For every 25 g of dried CR used, the mass of synthesized CMC yield is at an average of 23.8 g. The synthesized CMC is then grinded in controlled parameters using the ball milling machine to get the Nano-scale size. The particle size obtained from this is 43.32 Nm which is in range of Nano size. This study proved that Nano-size CMC has higher percentage of drag reduction (%DR and flow increase (%FI if compared to normal-size CMC when tested in high and low flow rate; 44% to 48% increase in %DR and %FI when tested in low flow rate, and 16% to 18% increase in %DR and %FI when tested in high flow rate. The success of this research shows that Nano-scale DRA can be considered to be used to have better performance in reducing drag.

Reconstruction of blood propagation in three-dimensional rotational X-ray angiography (3D-RA).

Science.gov (United States)

Schmitt, Holger; Grass, Michael; Suurmond, Rolf; Köhler, Thomas; Rasche, Volker; Hähnel, Stefan; Heiland, Sabine

2005-10-01

This paper presents a framework of non-interactive algorithms for the mapping of blood flow information to vessels in 3D-RA images. With the presented method, mapping of flow information to 3D-RA images is done automatically without user interaction. So far, radiologists had to perform this task by extensive image comparisons and did not obtain visualizations of the results. In our approach, flow information is reconstructed by forward projection of vessel pieces in a 3D-RA image to a two-dimensional projection series capturing the propagation of a short additional contrast agent bolus. For accurate 2D-3D image registration, an efficient patient motion compensation technique is introduced. As an exemplary flow-related quantity, bolus arrival times are reconstructed for the vessel pieces by matching of intensity-time curves. A plausibility check framework was developed which handles projection ambiguities and corrects for noisy flow reconstruction results. It is based on a linear programming approach to model the feeding structure of the vessel. The flow reconstruction method was applied to 12 cases of cerebral stenoses, AVMs and aneurysms, and it proved to be feasible in the clinical environment. The propagation of the injected contrast agent was reconstructed and visualized in three-dimensional images. The flow reconstruction method was able to visualize different types of useful information. In cases of stenosis of the middle cerebral artery (MCA), flow reconstruction can reveal impeded blood flow depending on the severeness of the stenosis. With cases of AVMs, flow reconstruction can clarify the feeding structure. The presented methods handle the problems imposed by clinical demands such as non-interactive algorithms, patient motion compensation, short reconstruction times, and technical requirements such as correction of noisy bolus arrival times and handling of overlapping vessel pieces. Problems occurred mainly in the reconstruction and segmentation of 3D-RA

Extreme Toughening of Soft Materials with Liquid Metal.

Science.gov (United States)

Kazem, Navid; Bartlett, Michael D; Majidi, Carmel

2018-05-01

Soft and tough materials are critical for engineering applications in medical devices, stretchable and wearable electronics, and soft robotics. Toughness in synthetic materials is mostly accomplished by increasing energy dissipation near the crack tip with various energy dissipation techniques. However, bio-materials exhibit extreme toughness by combining multi-scale energy dissipation with the ability to deflect and blunt an advancing crack tip. Here, we demonstrate a synthetic materials architecture that also exhibits multi-modal toughening, whereby embedding a suspension of micron sized and highly deformable liquid metal (LM) droplets inside a soft elastomer, the fracture energy dramatically increases by up to 50x (from 250 ± 50 J m -2 to 11,900 ± 2600 J m -2 ) over an unfilled polymer. For some LM-embedded elastomer (LMEE) compositions, the toughness is measured to be 33,500 ± 4300 J m -2 , which far exceeds the highest value previously reported for a soft elastic material. This extreme toughening is achieved by (i) increasing energy dissipation, (ii) adaptive crack movement, and (iii) effective elimination of the crack tip. Such properties arise from the deformability of the LM inclusions during loading, providing a new mechanism to not only prevent crack initiation, but also resist the propagation of existing tears for ultra tough, soft materials. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Linking MedDRA(®)-Coded Clinical Phenotypes to Biological Mechanisms by the Ontology of Adverse Events: A Pilot Study on Tyrosine Kinase Inhibitors.

Science.gov (United States)

Sarntivijai, Sirarat; Zhang, Shelley; Jagannathan, Desikan G; Zaman, Shadia; Burkhart, Keith K; Omenn, Gilbert S; He, Yongqun; Athey, Brian D; Abernethy, Darrell R

2016-07-01

A translational bioinformatics challenge exists in connecting population and individual clinical phenotypes in various formats to biological mechanisms. The Medical Dictionary for Regulatory Activities (MedDRA(®)) is the default dictionary for adverse event (AE) reporting in the US Food and Drug Administration Adverse Event Reporting System (FAERS). The ontology of adverse events (OAE) represents AEs as pathological processes occurring after drug exposures. The aim of this work was to establish a semantic framework to link biological mechanisms to phenotypes of AEs by combining OAE with MedDRA(®) in FAERS data analysis. We investigated the AEs associated with tyrosine kinase inhibitors (TKIs) and monoclonal antibodies (mAbs) targeting tyrosine kinases. The five selected TKIs/mAbs (i.e., dasatinib, imatinib, lapatinib, cetuximab, and trastuzumab) are known to induce impaired ventricular function (non-QT) cardiotoxicity. Statistical analysis of FAERS data identified 1053 distinct MedDRA(®) terms significantly associated with TKIs/mAbs, where 884 did not have corresponding OAE terms. We manually annotated these terms, added them to OAE by the standard OAE development strategy, and mapped them to MedDRA(®). The data integration to provide insights into molecular mechanisms of drug-associated AEs was performed by including linkages in OAE for all related AE terms to MedDRA(®) and the existing ontologies, including the human phenotype ontology (HP), Uber anatomy ontology (UBERON), and gene ontology (GO). Sixteen AEs were shared by all five TKIs/mAbs, and each of 17 cardiotoxicity AEs was associated with at least one TKI/mAb. As an example, we analyzed "cardiac failure" using the relations established in OAE with other ontologies and demonstrated that one of the biological processes associated with cardiac failure maps to the genes associated with heart contraction. By expanding the existing OAE ontological design, our TKI use case demonstrated that the combination

Development of Polymer Blends in order to Toughening of Polymers: A review

Directory of Open Access Journals (Sweden)

Carlos Bruno Barreto Luna

2015-05-01

Full Text Available Polymers are materials of large use in the various sectors of the world economy. The use of polymeric materials in daily life, instead of the classic materials has increased in recent decades. However, for certain structural applications polymers need to get tougher. One of the principal toughening techniques based on physical mixture of two or more components, forming the so-called polymer blends. The addition of rubber or not vulcanized in polymer compositions is reported in the literature as a means of generating mixtures of easy processing, and economically advantageous to increase the toughness of the thermoplastic matrix of interest. Moreover, it can be an alternative for the recycling of waste tires and footwear coming from industries, as well reduce harmful effects on the environment. Therefore, the present study aims to present a review of the definitions, benefits, thermodynamic fundamentals and toughening polymers.

Mechanical properties of hybrid SiC/CNT filled toughened epoxy nanocomposite

Science.gov (United States)

Ratim, S.; Ahmad, S.; Bonnia, N. N.; Yahaya, Sabrina M.

2018-01-01

Mechanical properties of epoxy nanocomposites filled single filler have been extensively studied by various researchers. However, there are not much discovery on the behavior of hybrid nanocomposite. In this study, single and hybrid nanocomposites of toughened epoxy filled CNT/SiC nanoparticles were investigated. The hybrid nanocomposites samples were prepared by combining CNT and SiC nanoparticles in toughened epoxy matrix via mechanical stirring method assisted with ultrasonic cavitations. Epoxy resin and liquid epoxidized natural rubber (LENR) mixture were first blend prior to the addition of nanofillers. Then, the curing process of the nanocomposite samples were conducted by compression molding technique at 130°C for 2 hours. The purpose of this study is to investigate the hybridization effect of CNT and SiC nanoparticles on mechanical properties toughened epoxy matrix. The total loading of single and hybrid nanofillers were fixed to 4% volume are 0, 4C, 4S, 3S1C, 2S2C, and 1S3C. Mechanical properties of hybrid composites show that the highest value of tensile strength achieved by 3S1C sample at about 7% increment and falls between their single composite values. Meanwhile, the stiffness of the same sample is significantly increased at about 31% of the matrix. On the other hand, a highest flexural property is obtained by 1S3C sample at about 20% increment dominated by CNT content. However, the impact strength shows reduction trend with the addition of SiC and CNT into the matrix. The hybridization of SiC and CNT show highest value in sample 1S3C at about 3.37 kJ/m2 of impact energy absorbed. FESEM micrograph have confirmed that better distributions and interaction observed between SiC nanoparticles and matrix compared to CNT, which contributed to higher tensile strength and modulus.

Diseño de antenas tipo DRA (Dielectric Resonator Antennas)

OpenAIRE

Soria Gallego, Juan

2013-01-01

En este trabajo se va a estudiar un tipo de antenas conocidas como antenas resonantes dieléctricas (DRA) desde el punto de vista de diseño y características radiantes, así como de sus posibles aplicaciones. Las DRAs son un tipo de antenas cada vez más usadas ya que presentan numerosas ventajas respecto a otro tipo de antenas, entre ellas que son fáciles de diseñar, baratas y muy eficientes. Por ello, cada vez aparecen nuevos diseños y nuevas aplicaciones. Entre ellas se ha extendido el uso...

Defining intrinsic vs. extrinsic atopic dermatitis.

Science.gov (United States)

Karimkhani, Chante; Silverberg, Jonathan I; Dellavalle, Robert P

2015-06-16

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin condition characterized by eczematous lesions, i.e. ill-demarcated erythematous patches and plaques. AD is commonly associated with elevated immunoglobulin E (IgE) and atopic disorders, such as asthma, hay fever, and food allergies. Rackemann and Mallory were some of the first to distinguish between asthma based on the presence ("extrinsic") or absence ("intrinsic") of allergy. This distinction has subsequently been applied to AD based on the presence ("extrinsic") or absence ("intrinsic") of increased IgE and atopic disease. Although the distinction between intrinsic and extrinsic AD is widely used, it remains controversial.

A structural study of the interaction between the Dr haemagglutinin DraE and derivatives of chloramphenicol

International Nuclear Information System (INIS)

Pettigrew, David M.; Roversi, Pietro; Davies, Stephen G.; Russell, Angela J.; Lea, Susan M.

2009-01-01

The structures of two Dr adhesin (DraE) complexes with chloramphenicol derivatives, namely chloramphenicol succinate and bromamphenicol, have been solved. The structures reveal important functional groups for small-molecule binding and imply possible modifications to the molecule that would permit a more wide-ranging interaction without the toxic side effects associated with chloramphenicol. Dr adhesins are expressed on the surface of uropathogenic and diffusely adherent strains of Escherichia coli. The major adhesin subunit (DraE/AfaE) of these organelles mediates attachment of the bacterium to the surface of the host cell and possibly intracellular invasion through its recognition of the complement regulator decay-accelerating factor (DAF) and/or members of the carcinoembryonic antigen (CEA) family. The adhesin subunit of the Dr haemagglutinin, a Dr-family member, additionally binds type IV collagen and is inhibited in all its receptor interactions by the antibiotic chloramphenicol (CLM). In this study, previous structural work is built upon by reporting the X-ray structures of DraE bound to two chloramphenicol derivatives: chloramphenicol succinate (CLS) and bromamphenicol (BRM). The CLS structure demonstrates that acylation of the 3-hydroxyl group of CLM with succinyl does not significantly perturb the mode of binding, while the BRM structure implies that the binding pocket is able to accommodate bulkier substituents on the N-acyl group. It is concluded that modifications of the 3@@hydroxyl group would generate a potent Dr haemagglutinin inhibitor that would not cause the toxic side effects that are associated with the normal bacteriostatic activity of CLM

Toughening elastomers with sacrificial bonds and watching them break

Science.gov (United States)

Creton, Costantino

2014-03-01

Most unfilled elastomers are relatively brittle, in particular when the average molecular weight between crosslinks is lower than the average molecular weight between entanglements. We created a new class of tough elastomers by introducing isotropically prestretched chains inside ordinary acrylic elastomers by successive swelling and polymerization steps. These new materials combine a high entanglement density with a densely crosslinked structure reaching elastic moduli of 4 MPa and fracture strength of 25 MPa. The highly prestretched chains are the minority in the material and can break in the bulk of the material before catastrophic failure occurs, increasing the toughness of the material by two orders of magnitude up to 5 kJ/m2. To investigate the details of the toughening mechanism we introduced specific sacrificial dioxetane bonds in the prestretched chains that emit light when they break. In uniaxial extension cyclic experiments, we checked that the light emission corresponded exactly and quantitatively to the energy dissipation in each cycle demonstrating that short chains break first and long chains later. We then watched crack propagation in notched samples and mapped spatially the location of bond breakage ahead of the crack tip before and during propagation. This new toughening mechanism for elastomers creates superentangled rubbers and is ideally suited to overcome the trade-off between toughness and stiffness of ordinary elastomers. We gratefully acknowledge funding from DSM Ahead

Dynamic Mechanical Properties and Fracture Surface Morphologies of Core-Shell Rubber (CSR) Toughened Epoxy at Liquid Nitrogen (Ln2) Temperatures

Science.gov (United States)

Wang, J.; Magee, D.; Schneider, J. A.

2009-01-01

The dynamic mechanical properties and fracture surface morphologies were evaluated for a commercial epoxy resin toughened with two types of core-shell rubber (CSR) toughening agents (Kane Ace(Registered TradeMark) MX130 and MX960). The impact resistance (R) was evaluated by the resulting breaking energy measured in Charpy impact tests conducted on an instrumented drop tower. The resulting fracture surface morphologies were examined using Scanning Electron Microscopy (SEM). Fractographic observations of the CSR toughened epoxy tested at ambient temperature, showed a fracture as characterized by slender dendrite textures with large voids. The increasing number of dendrites and decreasing size of scale-like texture with more CSR particles corresponded with increased R. As the temperature decreased to Liquid Nitrogen (LN 2), the fracture surfaces showed a fracture characterized by a rough, torn texture containing many river markings and deep furrows.

Asian International Graduate Students’ Extrinsic Motivation to Pursue Degrees

OpenAIRE

Naomi Takashiro

2017-01-01

The author examined the types of extrinsic motivation for Asian international graduate students pursuing graduate degrees. The theoretical framework used was extrinsic motivation within Self-Determination Theory. Even though the presence of Asian international graduate students is steadily increasing worldwide, research into their extrinsic motivation is scarce. It is important for educators to explore and understand Asian international graduate students’ extrinsic motivation since such stude...

Intrinsic and extrinsic motivation for smoking cessation.

Science.gov (United States)

Curry, S; Wagner, E H; Grothaus, L C

1990-06-01

An intrinsic-extrinsic model of motivation for smoking cessation was evaluated with 2 samples (ns = 1.217 and 151) of smokers who requested self-help materials for smoking cessation. Exploratory and confirmatory principal components analysis on a 36-item Reasons for Quitting (RFQ) scale supported the intrinsic-extrinsic motivation distinction. A 4-factor model, with 2 intrinsic dimensions (concerns about health and desire for self-control) and 2 extrinsic dimensions (immediate reinforcement and social influence), was defined by 20 of the 36 RFQ items. The 20-item measure demonstrated moderate to high levels of internal consistency and convergent and discriminant validity. Logistic regression analyses indicated that smokers with higher levels of intrinsic relative to extrinsic motivation were more likely to achieve abstinence from smoking.

CT Accuracy of Extrinsic Tongue Muscle Invasion in Oral Cavity Cancer.

Science.gov (United States)

Junn, J C; Baugnon, K L; Lacayo, E A; Hudgins, P A; Patel, M R; Magliocca, K R; Corey, A S; El-Deiry, M; Wadsworth, J T; Beitler, J J; Saba, N F; Liu, Y; Aiken, A H

2017-02-01

Extrinsic tongue muscle invasion in oral cavity cancer upstages the primary tumor to a T4a. Despite this American Joint Committee on Cancer staging criterion, no studies have investigated the accuracy or prognostic importance of radiologic extrinsic tongue muscle invasion, the feasibility of standardizing extrinsic tongue muscle invasion reporting, or the degree of agreement across different disciplines: radiology, surgery, and pathology. The purpose of this study was to assess the agreement among radiology, surgery, and pathology for extrinsic tongue muscle invasion and to determine the imaging features most predictive of extrinsic tongue muscle invasion with surgical/pathologic confirmation. Thirty-three patients with untreated primary oral cavity cancer were included. Two head and neck radiologists, 3 otolaryngologists, and 1 pathologist prospectively evaluated extrinsic tongue muscle invasion. Fourteen of 33 patients had radiologic extrinsic tongue muscle invasion; however, only 8 extrinsic tongue muscle invasions were confirmed intraoperatively. Pathologists were unable to determine extrinsic tongue muscle invasion in post-formalin-fixed samples. Radiologic extrinsic tongue muscle invasion had 100% sensitivity, 76% specificity, 57% positive predictive value, and 100% negative predictive value with concurrent surgical-pathologic evaluation of extrinsic tongue muscle invasion as the criterion standard. On further evaluation, the imaging characteristic most consistent with surgical-pathologic evaluation positive for extrinsic tongue muscle invasion was masslike enhancement. Evaluation of extrinsic tongue muscle invasion is a subjective finding for all 3 disciplines. For radiology, masslike enhancement of extrinsic tongue muscle invasion most consistently corresponded to concurrent surgery/pathology evaluation positive for extrinsic tongue muscle invasion. Intraoperative surgical and pathologic evaluation should be encouraged to verify radiologic extrinsic tongue

Thermomechanical response and toughening mechanisms of a carbon nano bead reinforced epoxy composite

Energy Technology Data Exchange (ETDEWEB)

Goyat, M.S., E-mail: goyatmanjeetsingh@gmail.com [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667 (India); Suresh, Sumit; Bahl, Sumit [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667 (India); Halder, Sudipta [Department of Mechanical Engineering, National Institute of Technology, Silchar, 788010, Assam (India); Ghosh, P.K. [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Roorkee, Roorkee, 247667 (India)

2015-09-15

The current research on carbon nano beads (CNB) is focused on various applications such as high strength nanocomposites, electronic devices, lubricants, semiconductors, and high-performance batteries, etc. The commercial uses of CNB are yet juvenile for the market. Only limited results have been published so far on CNB reinforced polymers [1]. This study highlights the synthesis of uniform size, spherical CNB using chemical vapour deposition (CVD) method. The synthesized CNB are introduced into epoxy matrix by ultrasonic dual mode mixing route to produce CNB/epoxy nanocomposite. The CNB are characterized by X-ray diffraction, Energy dispersive X-ray analysis and field emission scanning electron microscope (FESEM). Morphology, thermal and mechanical properties of the CNB/epoxy nanocomposites is characterized by FESEM, Thermo-gravimetric analyzer and tensile and bending tests respectively. A noticeable improvement in thermal and mechanical properties of CNB reinforced epoxy matrix with low nanofiller content is observed. Several toughening mechanisms such as particle pull out, crack deflection, particle bridging, crack pinning, shear yielding or plastic deformation, and microcracking are identified. But, only the crack deflection, particle bridging and shear yielding or plastic deformations are recognized as the leading toughening mechanisms for CNB/epoxy nanocomposite. These results can be considered as symptomatic of a potential CNB espousal in new composites. - Highlights: • Synthesis of uniform size, spherical CNB using chemical vapour deposition method. • Fabrication of CNB/epoxy nanocomposites by ultrasonic dual mode mixing route. • Significant enhancement in thermomechanical properties of CNB/epoxy nanocomposite. • Main toughening mechanisms: Crack deflection, particle bridging and shear yielding.

Thermomechanical response and toughening mechanisms of a carbon nano bead reinforced epoxy composite

International Nuclear Information System (INIS)

Goyat, M.S.; Suresh, Sumit; Bahl, Sumit; Halder, Sudipta; Ghosh, P.K.

2015-01-01

The current research on carbon nano beads (CNB) is focused on various applications such as high strength nanocomposites, electronic devices, lubricants, semiconductors, and high-performance batteries, etc. The commercial uses of CNB are yet juvenile for the market. Only limited results have been published so far on CNB reinforced polymers [1]. This study highlights the synthesis of uniform size, spherical CNB using chemical vapour deposition (CVD) method. The synthesized CNB are introduced into epoxy matrix by ultrasonic dual mode mixing route to produce CNB/epoxy nanocomposite. The CNB are characterized by X-ray diffraction, Energy dispersive X-ray analysis and field emission scanning electron microscope (FESEM). Morphology, thermal and mechanical properties of the CNB/epoxy nanocomposites is characterized by FESEM, Thermo-gravimetric analyzer and tensile and bending tests respectively. A noticeable improvement in thermal and mechanical properties of CNB reinforced epoxy matrix with low nanofiller content is observed. Several toughening mechanisms such as particle pull out, crack deflection, particle bridging, crack pinning, shear yielding or plastic deformation, and microcracking are identified. But, only the crack deflection, particle bridging and shear yielding or plastic deformations are recognized as the leading toughening mechanisms for CNB/epoxy nanocomposite. These results can be considered as symptomatic of a potential CNB espousal in new composites. - Highlights: • Synthesis of uniform size, spherical CNB using chemical vapour deposition method. • Fabrication of CNB/epoxy nanocomposites by ultrasonic dual mode mixing route. • Significant enhancement in thermomechanical properties of CNB/epoxy nanocomposite. • Main toughening mechanisms: Crack deflection, particle bridging and shear yielding.

Thermal shock behavior of toughened gadolinium zirconate/YSZ double-ceramic-layered thermal barrier coating

International Nuclear Information System (INIS)

Zhong, Xinghua; Zhao, Huayu; Zhou, Xiaming; Liu, Chenguang; Wang, Liang; Shao, Fang; Yang, Kai; Tao, Shunyan; Ding, Chuanxian

2014-01-01

Highlights: • Gd 2 Zr 2 O 7 /YSZ DCL thermal barrier coating was designed and fabricated. • The Gd 2 Zr 2 O 7 top ceramic layer was toughened by addition of nanostructured 3YSZ. • Remarkable improvement in thermal shock resistance of the DCL coating was achieved. - Abstract: Double-ceramic-layered (DCL) thermal barrier coating system comprising of toughened Gadolinium zirconate (Gd 2 Zr 2 O 7 , GZ) as the top ceramic layer and 4.5 mol% Y 2 O 3 partially-stabilized ZrO 2 (4.5YSZ) as the bottom ceramic layer was fabricated by plasma spraying and thermal shock behavior of the DCL coating was investigated. The GZ top ceramic layer was toughened by addition of nanostructured 3 mol% Y 2 O 3 partially-stabilized ZrO 2 (3YSZ) to improve fracture toughness of the matrix. The thermal shock resistance of the DCL coating was enhanced significantly compared to that of single-ceramic-layered (SCL) GZ-3YSZ composite coating, which is believed to be primarily attributed to the two factors: (i) the increase in fracture toughness of the top ceramic layer by incorporating nanostructured YSZ particles and (ii) the improvement in strain tolerance through the utilization of 4.5YSZ as the bottom ceramic layer. In addition, the failure mechanisms are mainly attributed to the still low fracture toughness of the top ceramic layer and oxidation of the bond-coat

Diffusion by extrinsic noise in the kicked Harper map

International Nuclear Information System (INIS)

Park, Gunyoung; Chang, C. S.

2001-01-01

A significantly improved analytic understanding of the extrinsically driven diffusion process is presented in a nonlinear dynamical system in which the phase space is divided into periodic two-dimensional tiles of regular motion, separated by a connected separatrix network (web) [previously studied by A. J. Lichtenberg and Blake P. Wood, Phys. Rev. Lett. >62, 2213 (1989)]. The system is represented by the usual 'kicked Harper map' with added extrinsic noise terms. Three different diffusion regimes are found depending upon the strength of the extrinsic perturbation l relative to the web and regular motions. When the extrinsic noise is dominant over the intrinsic stochasticity and the regular rotation motions in the tile, diffusion obeys the random phase scaling l 2 . When the extrinsic noise is dominant over the intrinsic stochasticity, but weaker than the regular rotation motion, the diffusion scales as lK 1/2 , where K is the strength of the intrinsic kick. These findings agree well with numerical simulation results. When the extrinsic noise process is weaker than the stochastic web process, we analytically reproduce the well-known numerical result: The web diffusion is reduced by the ratio of phase-space areas of intrinsic to extrinsic stochasticity

Molecular nanomechanics of nascent bone: fibrillar toughening by mineralization

Science.gov (United States)

Buehler, Markus J.

2007-07-01

Mineralized collagen fibrils are highly conserved nanostructural building blocks of bone. By a combination of molecular dynamics simulation and theoretical analysis it is shown that the characteristic nanostructure of mineralized collagen fibrils is vital for its high strength and its ability to sustain large deformation, as is relevant to the physiological role of bone, creating a strong and tough material. An analysis of the molecular mechanisms of protein and mineral phases under large deformation of mineralized collagen fibrils reveals a fibrillar toughening mechanism that leads to a manifold increase of energy dissipation compared to fibrils without mineral phase. This fibrillar toughening mechanism increases the resistance to fracture by forming large local yield regions around crack-like defects, a mechanism that protects the integrity of the entire structure by allowing for localized failure. As a consequence, mineralized collagen fibrils are able to tolerate microcracks of the order of several hundred micrometres in size without causing any macroscopic failure of the tissue, which may be essential to enable bone remodelling. The analysis proves that adding nanoscopic small platelets to collagen fibrils increases their Young's modulus and yield strength as well as their fracture strength. We find that mineralized collagen fibrils have a Young's modulus of 6.23 GPa (versus 4.59 GPa for the collagen fibril), yield at a tensile strain of 6.7% (versus 5% for the collagen fibril) and feature a fracture stress of 0.6 GPa (versus 0.3 GPa for the collagen fibril).

Molecular nanomechanics of nascent bone: fibrillar toughening by mineralization

International Nuclear Information System (INIS)

Buehler, Markus J

2007-01-01

Mineralized collagen fibrils are highly conserved nanostructural building blocks of bone. By a combination of molecular dynamics simulation and theoretical analysis it is shown that the characteristic nanostructure of mineralized collagen fibrils is vital for its high strength and its ability to sustain large deformation, as is relevant to the physiological role of bone, creating a strong and tough material. An analysis of the molecular mechanisms of protein and mineral phases under large deformation of mineralized collagen fibrils reveals a fibrillar toughening mechanism that leads to a manifold increase of energy dissipation compared to fibrils without mineral phase. This fibrillar toughening mechanism increases the resistance to fracture by forming large local yield regions around crack-like defects, a mechanism that protects the integrity of the entire structure by allowing for localized failure. As a consequence, mineralized collagen fibrils are able to tolerate microcracks of the order of several hundred micrometres in size without causing any macroscopic failure of the tissue, which may be essential to enable bone remodelling. The analysis proves that adding nanoscopic small platelets to collagen fibrils increases their Young's modulus and yield strength as well as their fracture strength. We find that mineralized collagen fibrils have a Young's modulus of 6.23 GPa (versus 4.59 GPa for the collagen fibril), yield at a tensile strain of 6.7% (versus 5% for the collagen fibril) and feature a fracture stress of 0.6 GPa (versus 0.3 GPa for the collagen fibril)

Theoretical and experimental analysis of the toughening behavior of whisker reinforcement in ceramic matrix composites

International Nuclear Information System (INIS)

Becher, P.F.; Hsueh, C.H.; Angelini, P.; Tiegs, T.N.

1988-01-01

Analytical solutions are presented describing the experimentally verified toughening of whisker reinforced ceramics. Clear insights are provided into the interrelationships of whiskers, matrices, and interfaces in the case of strong interfaces with minimized whisker pullout

Regularized strings with extrinsic curvature

International Nuclear Information System (INIS)

Ambjoern, J.; Durhuus, B.

1987-07-01

We analyze models of discretized string theories, where the path integral over world sheet variables is regularized by summing over triangulated surfaces. The inclusion of curvature in the action is a necessity for the scaling of the string tension. We discuss the physical properties of models with extrinsic curvature terms in the action and show that the string tension vanishes at the critical point where the bare extrinsic curvature coupling tends to infinity. Similar results are derived for models with intrinsic curvature. (orig.)

Wide Bandgap Extrinsic Photoconductive Switches

Energy Technology Data Exchange (ETDEWEB)

Sullivan, James S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2013-07-03

Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6HSiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators.

SPM and XPM crosstalk in WDM systems with DRA: Channel spacing and attenuation effects

Science.gov (United States)

Morsy, Emadeldeen; Fayed, Heba A.; Abd El Aziz, Ahmed; Aly, Moustafa H.

2018-06-01

This paper presents a theoretical analysis of a closed formula for nonlinear crosstalk due to self-phase modulation (SPM) and cross phase modulation (XPM) in wavelength division multiplexing (WDM) systems. The influence of channel spacing and attenuation on the system behavior is modeled and investigated. The system under consideration is a standard single-mode fiber (SSMF) with a single-span distributed Raman amplifier (DRA) and is operating at 100 Gbps.

Microstructure, Mechanical Properties, and Toughening Mechanisms of a New Hot Stamping-Bake Toughening Steel

Science.gov (United States)

Lin, Tao; Song, Hong-Wu; Zhang, Shi-Hong; Cheng, Ming; Liu, Wei-Jie; Chen, Yun

2015-09-01

In this article, the hot stamping-bake toughening process has been proposed following the well-known concept of bake hardening. The influences of the bake time on the microstructure and the mechanical properties of the hot stamped-baked part were studied by means of scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and mechanical tests at room temperature. The results show that the amount of the retained austenite was nearly not changed by the bake process. Also observed were spherical Cu-rich precipitates of about 15 nm in martensite laths. According to the Orowan mechanism, their contribution of the Cu-rich precipitates to the strength is approximately 245 MPa. With the increase of the bake time, the tensile strength of the part was decreased, whereas both the ductility and the product of the tensile strength and ductility were increased then decreased. The tensile strength and ductility product and the tensile strength are as high as 21.9 GPa pct, 2086 MPa, respectively. The excellent combined properties are due to the transformation-induced plasticity effect caused by retained austenite.

Extrinsic value orientation and affective forecasting: overestimating the rewards, underestimating the costs.

Science.gov (United States)

Sheldon, Kennon M; Gunz, Alexander; Nichols, Charles P; Ferguson, Yuna

2010-02-01

We examined affective forecasting errors as a possible explanation of the perennial appeal of extrinsic values and goals. Study 1 found that although people relatively higher in extrinsic (money, fame, image) compared to intrinsic (growth, intimacy, community) value orientation (REVO) are less happy, they nevertheless believe that attaining extrinsic goals offers a strong potential route to happiness. Study 2's longitudinal experimental design randomly assigned participants to pursue either 3 extrinsic or 3 intrinsic goals over 4 weeks, and REVO again predicted stronger forecasts regarding extrinsic goals. However, not even extrinsically oriented participants gained well-being benefits from attaining extrinsic goals, whereas all participants tended to gain in happiness from attaining intrinsic goals. Study 3 showed that the effect of REVO on forecasts is mediated by extrinsic individuals' belief that extrinsic goals will satisfy autonomy and competence needs. It appears that some people overestimate the emotional benefits of achieving extrinsic goals, to their potential detriment.

Deriving common comorbidity indices from the MedDRA classification and exploring their performance on key outcomes in patients with rheumatoid arthritis.

Science.gov (United States)

Putrik, Polina; Ramiro, Sofia; Lie, Elisabeth; Michaud, Kaleb; Kvamme, Maria K; Keszei, Andras P; Kvien, Tore K; Uhlig, Till; Boonen, Annelies

2018-03-01

To develop algorithms for calculating the Rheumatic Diseases Comorbidity Index (RDCI), Charlson-Deyo Index (CDI) and Functional Comorbidity Index (FCI) from the Medical Dictionary for Regulatory Activities (MedDRA), and to assess how these MedDRA-derived indices predict clinical outcomes, utility and health resource utilization (HRU). Two independent researchers linked the preferred terms of the MedDRA classification into the conditions included in the RDCI, the CDI and the FCI. Next, using data from the Norwegian Register-DMARD study (a register of patients with inflammatory joint diseases treated with DMARDs), the explanatory value of these indices was studied in models adjusted for age, gender and DAS28. Model fit statistics were compared in generalized estimating equation (prediction of outcome over time) models using as outcomes: modified HAQ, HAQ, physical and mental component summary of SF-36, SF6D and non-RA related HRU. Among 4126 patients with RA [72% female, mean (s.d.) age 56 (14) years], median (interquartile range) of RDCI at baseline was 0.0 (1.0) [range 0-6], CDI 0.0 (0.0) [0-7] and FCI 0.0 (1.0) [0-6]. All the comorbidity indices were associated with each outcome, and differences in their performance were moderate. The RDCI and FCI performed better on clinical outcomes: modified HAQ and HAQ, hospitalization, physical and mental component summary, and SF6D. Any non-RA related HRU was best predicted by RDCI followed by CDI. An algorithm is now available to compute three commonly used comorbidity indices from MedDRA classification. Indices performed comparably well in predicting a variety of outcomes, with the CDI performing slightly worse when predicting outcomes reflecting functioning and health. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Learning from evolutionary optimisation: what are toughening mechanisms good for in dentine, a nonrepairing bone tissue?

Science.gov (United States)

Zaslansky, Paul; Currey, John D; Fleck, Claudia

2016-09-12

The main mass of material found in teeth is dentine, a bone-like tissue, riddled with micron-sized tubules and devoid of living cells. It provides support to the outer wear-resistant layer of enamel, and exhibits toughening mechanisms which contribute to crack resistance. And yet unlike most bone tissues, dentine does not remodel and consequently any accumulated damage does not 'self repair'. Because damage containment followed by tissue replacement is a prime reason for the crack-arresting microstructures found in most bones, the occurrence of toughening mechanisms without the biological capability to repair is puzzling. Here we consider the notion that dentine might be overdesigned for strength, because it has to compensate for the lack of cell-mediated healing mechanisms. Based on our own and on literature-reported observations, including quasistatic and fatigue properties, dentine design principles are discussed in light of the functional conditions under which teeth evolved. We conclude that dentine is only slightly overdesigned for everyday cyclic loading because usual mastication stresses may come close to its endurance strength. The in-built toughening mechanisms constitute an evolutionary benefit because they prevent catastrophic failure during rare overload events, which was probably very advantageous in our hunter gatherer ancestor times. From a bio-inspired perspective, understanding the extent of evolutionary overdesign might be useful for optimising biomimetic structures used for load bearing.

Distinct molecular signatures of mild extrinsic and intrinsic atopic dermatitis

DEFF Research Database (Denmark)

Martel, Britta Cathrina; Litman, Thomas; Hald, Andreas

2016-01-01

Atopic dermatitis (AD) is a common inflammatory skin disease with underlying defects in epidermal function and immune responses. In this study, we used microarray analysis to investigate differences in gene expression in lesional skin from patients with mild extrinsic or intrinsic AD compared...... with mild extrinsic and intrinsic AD similar to previous reports for severe AD. Interestingly, expression of genes involved in inflammatory responses in intrinsic AD resembled that of psoriasis more than that of extrinsic AD. Overall, differences in expression of inflammation-associated genes found among...... patients with mild intrinsic and extrinsic AD correlated with previous findings for patients with severe intrinsic and extrinsic AD....

Asian International Graduate Students’ Extrinsic Motivation to Pursue Degrees

Directory of Open Access Journals (Sweden)

Naomi Takashiro

2017-04-01

Full Text Available The author examined the types of extrinsic motivation for Asian international graduate students pursuing graduate degrees. The theoretical framework used was extrinsic motivation within Self-Determination Theory. Even though the presence of Asian international graduate students is steadily increasing worldwide, research into their extrinsic motivation is scarce. It is important for educators to explore and understand Asian international graduate students’ extrinsic motivation since such students would provide unique, distinctive cultural aspects in the classroom in their host countries. The research design employed was qualitative. Semi-structured interviews were conducted with 10 graduate students from four Asian countries. The identified themes were a faculty influence, b personal recognition, and c utility for careers. Asian international graduate students expressed that their ultimate extrinsic motivation was to get professional jobs in academia. The author discussed the implications of these findings for instructors.

Intrinsic and Extrinsic Neuromodulation of Olfactory Processing.

Science.gov (United States)

Lizbinski, Kristyn M; Dacks, Andrew M

2017-01-01

Neuromodulation is a ubiquitous feature of neural systems, allowing flexible, context specific control over network dynamics. Neuromodulation was first described in invertebrate motor systems and early work established a basic dichotomy for neuromodulation as having either an intrinsic origin (i.e., neurons that participate in network coding) or an extrinsic origin (i.e., neurons from independent networks). In this conceptual dichotomy, intrinsic sources of neuromodulation provide a "memory" by adjusting network dynamics based upon previous and ongoing activation of the network itself, while extrinsic neuromodulators provide the context of ongoing activity of other neural networks. Although this dichotomy has been thoroughly considered in motor systems, it has received far less attention in sensory systems. In this review, we discuss intrinsic and extrinsic modulation in the context of olfactory processing in invertebrate and vertebrate model systems. We begin by discussing presynaptic modulation of olfactory sensory neurons by local interneurons (LNs) as a mechanism for gain control based on ongoing network activation. We then discuss the cell-class specific effects of serotonergic centrifugal neurons on olfactory processing. Finally, we briefly discuss the integration of intrinsic and extrinsic neuromodulation (metamodulation) as an effective mechanism for exerting global control over olfactory network dynamics. The heterogeneous nature of neuromodulation is a recurring theme throughout this review as the effects of both intrinsic and extrinsic modulation are generally non-uniform.

Evaluation of advanced transformation toughened zirconia

International Nuclear Information System (INIS)

Swab, J.J.

1986-01-01

Transformation toughened zirconia (TTZ) is a material being considered for use in advanced heat engines. However, at elevated temperatures TTZ materials undergo a phase transformation from tetragonal to the monoclinic with an associated volume increase of approximately 5%. This transformation results in a loss of strength and fracture toughness. Six commercially available Japanese TTZ materials and one experimental domestic grade were examined for the extent and effect of this phase transformation after exposure to elevated temperatures (1000 to 1200 0 C) for times of 100 and 500 hours. Strength losses after heat treatment at 1000 0 C for 100 and 500 hours, ranged from a high of 60% to as little as 7%. Additional heat treatments of 500 hours at 1100 and 1200 0 C were carried out on TTZ's which had strength losses of 15% or less after exposure to 1000 0 C

Microwave sintering of zirconia toughened alumina at 28GHz

International Nuclear Information System (INIS)

Samandi, M.; Ji, H.; Miyake, S.

1998-01-01

Microwave radiation from a 10 kW, CW gyrotron operating at 28 GHz was employed to sinter 10% zirconia toughened alumina (ZTA) ceramic samples. It has been established that the use of millimetre wave radiation circumvents the difficulties encountered during the sintering of ceramics, i e. formation of hot spot, by radiation at industrially permissible frequency of 2.45GHz. Further, careful density measurement and microstructural characterisation of mm- wave and conventionally sintered samples by XRD, SEM and TEM has unequivocally demonstrated the effectiveness of mm-wave radiation for obtaining high density ceramics at lower sintering temperatures. Copyright (1998) Australasian Ceramic Society

Multi-scale modelling of non-uniform consolidation of uncured toughened unidirectional prepregs

Science.gov (United States)

Sorba, G.; Binetruy, C.; Syerko, E.; Leygue, A.; Comas-Cardona, S.; Belnoue, J. P.-H.; Nixon-Pearson, O. J.; Ivanov, D. S.; Hallett, S. R.; Advani, S. G.

2018-05-01

Consolidation is a crucial step in manufacturing of composite parts with prepregs because its role is to eliminate inter- and intra-ply gaps and porosity. Some thermoset prepreg systems are toughened with thermoplastic particles. Depending on their size, thermoplastic particles can be either located in between plies or distributed within the inter-fibre regions. When subjected to transverse compaction, resin will bleed out of low-viscosity unidirectional prepregs along the fibre direction, whereas one would expect transverse squeeze flow to dominate for higher viscosity prepregs. Recent experimental work showed that the consolidation of uncured toughened prepregs involves complex flow and deformation mechanisms where both bleeding and squeeze flow patterns are observed [1]. Micrographs of compacted and cured samples confirm these features as shown in Fig.1. A phenomenological model was proposed [2] where bleeding flow and squeeze flow are combined. A criterion for the transition from shear flow to resin bleeding was also proposed. However, the micrographs also reveal a resin rich layer between plies which may be contributing to the complex flow mechanisms during the consolidation process. In an effort to provide additional insight into these complex mechanisms, this work focuses on the 3D numerical modelling of the compaction of uncured toughened prepregs in the cross-ply configuration described in [1]. A transversely isotropic fluid model is used to describe the flow behaviour of the plies coupled with interplay resin flow of an isotropic fluid. The multi-scale flow model used is based on [3, 4]. A numerical parametric study is carried out where the resin viscosity, permeability and inter-ply thickness are varied to identify the role of important variables. The squeezing flow and the bleeding flow are compared for a range of process parameters to investigate the coupling and competition between the two flow mechanisms. Figure 4 shows the predicted displacement of

Does extrinsic goal framing enhance extrinsic goal-oriented individuals' learning and performance? An experimental test of the match perspective versus self-determination theory

OpenAIRE

Vansteenkiste, Maarten; Timmermans, Tinneke; Lens, Willy; Soenens, Bart; Van den Broeck, Anja

2008-01-01

Previous work within self-determination theory has shown that experimentally framing a learning activity in terms of extrinsic rather than intrinsic goals results in poorer conceptual learning and performance, presumably because extrinsic goal framing detracts attention from the learning activity and is less directly satisfying of basic psychological needs. According to the match perspective, experimental extrinsic, compared to intrinsic, goal framing should enhance learning and performance f...

Tribological properties of toughened zirconia-based ceramics

International Nuclear Information System (INIS)

Stachowiak, G.W.; Stachowiak, G.B.

1991-01-01

The physical and mechanical properties of toughened zirconia ceramics are briefly characterized and described with a special emphasis on their tribological behaviour. The wear and friction properties of PSZ and TZP ceramics at room and elevated temperatures are described. The influence of the environment on the tribological characteristics of zirconia ceramics is discussed. Both lubricated and unlubricated conditions for ceramic/ceramic and metal/ceramic sliding contacts are analysed. One of the main, and as yet unresolved problems, lubrication of ceramic at elevated temperatures and/or space environment, is addressed and the possible solutions to the problem are suggested. The critical needs in the research and development area of improving the tribological properties of zirconia ceramics are defined and its future market potentials stated. 30 refs., 2 tabs., 4 figs

Ética, comunicación interna y rendimiento laboral en el Instituto Nacional de Rehabilitación “Dra. Adriana Rebaza Flores”-Minsa. Lima. 2016

OpenAIRE

Rodríguez Vargas, Martha Aida

2016-01-01

La presente investigación tuvo como objetivo general determinar la relación entre la Ética, comunicación interna y rendimiento laboral en el Instituto Nacional de Rehabilitación “Dra. Adriana Rebaza Flores”-Minsa. Lima. 2016. La población o universo de interés en esta investigación, estuvo conformada por 60 Médicos Rehabilitadores del Instituto Nacional de Rehabilitación “Dra. Adriana Rebaza Flores”. Minsa, la muestra censal considero al mismo número de la población en las cual...

Do people differentiate between intrinsic and extrinsic goals for physical activity?

Science.gov (United States)

McLachlan, Sarah; Hagger, Martin S

2011-04-01

The distinction between intrinsic and extrinsic goals, and between goal pursuit for intrinsically and extrinsically motivated reasons, is a central premise of self-determination theory. Proponents of the theory have proposed that the pursuit of intrinsic goals and intrinsically motivated goal striving each predict adaptive psychological and behavioral outcomes relative to the pursuit of extrinsic goals and extrinsically motivated goal striving. Despite evidence to support these predictions, research has not explored whether individuals naturally differentiate between intrinsic and extrinsic goals. Two studies tested whether people make this differentiation when recalling goals for leisure-time physical activity. Using memory-recall methods, participants in Study 1 were asked to freely generate physical activity goals. A subsample (N = 43) was asked to code their freely generated goals as intrinsic or extrinsic. In Study 2, participants were asked to recall intrinsic and extrinsic goals after making a decision regarding their future physical activity. Results of these studies revealed that individuals' goal generation and recall exhibited significant clustering by goal type. Participants encountered some difficulties when explicitly coding goals. Findings support self-determination theory and indicate that individuals discriminate between intrinsic and extrinsic goals.

Hybrid Carbon-Glass Fiber/Toughened Epoxy Thick Composite Joints Subject to Drop-Weight and Ballistic Impacts

National Research Council Canada - National Science Library

Liaw, Benjamin; Delale, Feridun

2007-01-01

... No. DAAD19-02-R-0010 to conduct research on hybrid carbon-S2 glass fiber/toughened epoxy thick-section, hybrid interwoven composite joints subject to drop-weight and ballistic impacts. Dr. Basavaraju B. Raju of U.S...

On the isoperimetric rigidity of extrinsic minimal balls

DEFF Research Database (Denmark)

Markvorsen, Steen; Palmer, V.

2003-01-01

We consider an m-dimensional minimal submanifold P and a metric R-sphere in the Euclidean space R-n. If the sphere has its center p on P, then it will cut out a well defined connected component of P which contains this center point. We call this connected component an extrinsic minimal R-ball of P....... The quotient of the volume of the extrinsic ball and the volume of its boundary is not larger than the corresponding quotient obtained in the space form standard situation, where the minimal submanifold is the totally geodesic linear subspace R-m. Here we show that if the minimal submanifold has dimension...... larger than 3, if P is not too curved along the boundary of an extrinsic minimal R-ball, and if the inequality alluded to above is an equality for the extrinsic minimal ball, then the minimal submanifold is totally geodesic....

Knowledge and tools formalization in the accidental risks domain (DRA-35) {omega}-13 Boilover; Formalisation du savoir et des outils dans le domaine des risques accidentels (DRA-35) {omega}-13 BOILOVER

Energy Technology Data Exchange (ETDEWEB)

Patej, S

2003-03-15

Since 2000 the Ministry of the environment is financing a studies and researches program, called since 2003 ''formalization of the knowledge and tools in the domain of the major risks'' DRA-35. The aim of this program is to realize a document formalizing the INERIS expertise in the domain of the accidental risks: the physical phenomenon implied in the accidents, the risks analysis and control, the methodological aspects for the realization of regulations. This report presents the study of the boilover physical phenomenon. (A.L.B.)

Toughening MoSi2 with Niobium metal -- Effects of size and orientation of ductile laminae

International Nuclear Information System (INIS)

Shaw, L.; Abbaschian, R.

1994-01-01

Effects of size and orientation of ductile laminae on the toughness of brittle matrix composites have been evaluated using MoSi 2 composites reinforced with Nb laminae. Nb laminae with thicknesses ranging from 0.127 to 1.0 mm were hot pressed with MoSi 2 powder to prepare the composites. Toughness of the composites was measured using four-point bend test on chevron-notched specimens. It was found that the toughness of the composites increased with increasing size of the niobium laminae. Furthermore, toughening was observed at crack propagation directions perpendicular to the laminae plane, indicating that ductile laminae offer two dimensional toughening. A model based on the bridging contribution of the ductile phase has been proposed to analyze the chevron-notched specimens of the ductile-phase-reinforced brittle matrix composites. The analysis showed that the dependence of the toughness of the composites on the size and orientation of the ductile laminae could be interpreted in terms of their bridging capability and bending contributions

Intrinsic and extrinsic effects on image memorability.

Science.gov (United States)

Bylinskii, Zoya; Isola, Phillip; Bainbridge, Constance; Torralba, Antonio; Oliva, Aude

2015-11-01

Previous studies have identified that images carry the attribute of memorability, a predictive value of whether a novel image will be later remembered or forgotten. Here we investigate the interplay between intrinsic and extrinsic factors that affect image memorability. First, we find that intrinsic differences in memorability exist at a finer-grained scale than previously documented. Second, we test two extrinsic factors: image context and observer behavior. Building on prior findings that images that are distinct with respect to their context are better remembered, we propose an information-theoretic model of image distinctiveness. Our model can automatically predict how changes in context change the memorability of natural images. In addition to context, we study a second extrinsic factor: where an observer looks while memorizing an image. It turns out that eye movements provide additional information that can predict whether or not an image will be remembered, on a trial-by-trial basis. Together, by considering both intrinsic and extrinsic effects on memorability, we arrive at a more complete and fine-grained model of image memorability than previously available. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sub-10-micrometer toughening and crack tip toughness of dental enamel

OpenAIRE

Ang, Siang Fung; Schulz, Anja; Pacher Fernandes, Rodrigo; Schneider, Gerold A.

2011-01-01

In previous studies, enamel showed indications to occlude small cracks in-vivo and exhibited R-curve behaviors for bigger cracks ex-vivo. This study quantifies the crack tip toughness (KI0, KIII0), the crack closure stress and the cohesive zone size at the crack tip of enamel and investigates the toughening mechanisms near the crack tip down to the length scale of a single enamel crystallite. The crack-opening-displacement (COD) profile of cracks induced by Vickers indents on mature bovine en...

Self-perception of intrinsic and extrinsic motivation.

Science.gov (United States)

Calder, B J; Staw, B M

1975-04-01

Self-perception theory predicts that intrinsic and extrinsic motivation do not combine additively but rather interact. To test this predicted interaction, intrinsic and extrinsic motivation were both manipulated as independent variables. The results revealed a significant interaction for task satisfaction and a trend for the interaction on a behavioral measure. These results are discussed in terms of a general approach to the self-perception of motivation.

Separating intrinsic from extrinsic fluctuations in dynamic biological systems.

Science.gov (United States)

Hilfinger, Andreas; Paulsson, Johan

2011-07-19

From molecules in cells to organisms in ecosystems, biological populations fluctuate due to the intrinsic randomness of individual events and the extrinsic influence of changing environments. The combined effect is often too complex for effective analysis, and many studies therefore make simplifying assumptions, for example ignoring either intrinsic or extrinsic effects to reduce the number of model assumptions. Here we mathematically demonstrate how two identical and independent reporters embedded in a shared fluctuating environment can be used to identify intrinsic and extrinsic noise terms, but also how these contributions are qualitatively and quantitatively different from what has been previously reported. Furthermore, we show for which classes of biological systems the noise contributions identified by dual-reporter methods correspond to the noise contributions predicted by correct stochastic models of either intrinsic or extrinsic mechanisms. We find that for broad classes of systems, the extrinsic noise from the dual-reporter method can be rigorously analyzed using models that ignore intrinsic stochasticity. In contrast, the intrinsic noise can be rigorously analyzed using models that ignore extrinsic stochasticity only under very special conditions that rarely hold in biology. Testing whether the conditions are met is rarely possible and the dual-reporter method may thus produce flawed conclusions about the properties of the system, particularly about the intrinsic noise. Our results contribute toward establishing a rigorous framework to analyze dynamically fluctuating biological systems.

VOL 6. NO. 1 2015 EXTRINSIC FACTORS THAT AFFECT ...

African Journals Online (AJOL)

Frederick Iraki

Keywords: Job satisfaction, clergy, extrinsic motivation, extrinsic factors ... woman's work conditions and rewards are inferior to those of a man in comparable positions (a ... that they have embraced the need to professionalize their systems.

Knowledge and tools formalization in the accidental risks domain (DRA-35) Ω-13 Boilover

International Nuclear Information System (INIS)

Patej, S.

2003-03-01

Since 2000 the Ministry of the environment is financing a studies and researches program, called since 2003 ''formalization of the knowledge and tools in the domain of the major risks'' DRA-35. The aim of this program is to realize a document formalizing the INERIS expertise in the domain of the accidental risks: the physical phenomenon implied in the accidents, the risks analysis and control, the methodological aspects for the realization of regulations. This report presents the study of the boilover physical phenomenon. (A.L.B.)

Intrinsic and extrinsic factors influencing large African herbivore movements

NARCIS (Netherlands)

Venter, J.A.; Prins, H.H.T.; Mashanova, A.; Boer, de W.F.; Slotow, R.

2015-01-01

Understanding environmental as well as anthropogenic factors that influence large herbivore ecological patterns and processes should underpin their conservation and management. We assessed the influence of intrinsic, extrinsic environmental and extrinsic anthropogenic factors on movement behaviour

Do intrinsic and extrinsic motivation relate differently to employee outcomes?

OpenAIRE

Kuvaas, Bard; Buch, Robert; Weibel, Antoinette; Dysvik, Anders; Nerstad, Christina

2017-01-01

In most theories that address how individual financial incentives affect work performance, researchers have assumed that two types of motivation—intrinsic and extrinsic—mediate the relationship between incentives and performance. Empirically, however, extrinsic motivation is rarely investigated. To explore the predictive validity of these theories of intrinsic and extrinsic motivation in work settings, we tested how both intrinsic and extrinsic motivation affected supervisor-ra...

Extrinsic versus intrinsic hand muscle dominance in finger flexion.

Science.gov (United States)

Al-Sukaini, A; Singh, H P; Dias, J J

2016-05-01

This study aims to identify the patterns of dominance of extrinsic or intrinsic muscles in finger flexion during initiation of finger curl and mid-finger flexion. We recorded 82 hands of healthy individuals (18-74 years) while flexing their fingers and tracked the finger joint angles of the little finger using video motion tracking. A total of 57 hands (69.5%) were classified as extrinsic dominant, where the finger flexion was initiated and maintained at proximal interphalangeal and distal interphalangeal joints. A total of 25 (30.5%) were classified as intrinsic dominant, where the finger flexion was initiated and maintained at the metacarpophalangeal joint. The distribution of age, sex, dominance, handedness and body mass index was similar in the two groups. This knowledge may allow clinicians to develop more efficient rehabilitation regimes, since intrinsic dominant individuals would not initiate extrinsic muscle contraction till later in finger flexion, and might therefore be allowed limited early active motion. For extrinsic dominant individuals, by contrast, initial contraction of extrinsic muscles would place increased stress on the tendon repair site if early motion were permitted. © The Author(s) 2016.

Prototype evaluation of transformation toughened blast resistant naval hull steels: Part II

Science.gov (United States)

Saha, A.; Jung, J.; Olson, G. B.

2007-07-01

Application of a systems approach to computational materials design led to the theoretical design of a transformation toughened ultratough high-strength plate steel for blast-resistant naval hull applications. A first prototype alloy has achieved property goals motivated by projected naval hull applications requiring extreme fracture toughness (C v > 85 ft-lbs or 115 J corresponding to K Id≥ 200 ksi.in1/2 or 220 MPa.m1/2) at strength levels of 150 180 ksi (1,030 1,240 MPa) yield strength in weldable, formable plate steels. A continuous casting process was simulated by slab casting the prototype alloy as a 1.75‧‧ (4.45 cm) plate. Consistent with predictions, compositional banding in the plate was limited to an amplitude of 6 7.5 wt% Ni and 3.5 5 wt% Cu. Examination of the oxide scale showed no evidence of hot shortness in the alloy during hot working. Isothermal transformation kinetics measurements demonstrated achievement of 50% bainite in 4 min at 360 °C. Hardness and tensile tests confirmed predicted precipitation strengthening behavior in quench and tempered material. Multi-step tempering conditions were employed to achieve the optimal austenite stability resulting in significant increase of impact toughness to 130 ft-lb (176 J) at a strength level of 160 ksi (1,100 MPa). Comparison with the baseline toughness strength combination determined by isochronal tempering studies indicates a transformation toughening increment of 65% in Charpy energy. Predicted Cu particle number densities and the heterogeneous nucleation of optimal stability high Ni 5 nm austenite on nanometer-scale copper precipitates in the multi-step tempered samples was confirmed using three-dimensional atom probe microanalysis. Charpy impact tests and fractography demonstrate ductile fracture with C v > 80 ft-lbs (108 J) down to -40 °C, with a substantial toughness peak at 25 °C consistent with designed transformation toughening behavior. The properties demonstrated in this first

Extrinsic Isoperimetric Analysis on Submanifolds with Curvatures bounded from below

DEFF Research Database (Denmark)

Markvorsen, Steen; Palmer, Vicente

2010-01-01

and on the radial part of the intrinsic unit normals at the boundaries of the extrinsic spheres, respectively. In the same vein we also establish lower bounds on the mean exit time for Brownian motions in the extrinsic balls, i.e. lower bounds for the time it takes (on average) for Brownian particles to diffuse......We obtain upper bounds for the isoperimetric quotients of extrinsic balls of submanifolds in ambient spaces which have a lower bound on their radial sectional curvatures. The submanifolds are themselves only assumed to have lower bounds on the radial part of the mean curvature vector field...... within the extrinsic ball from a given starting point before they hit the boundary of the extrinsic ball. In those cases, where we may extend our analysis to hold all the way to infinity, we apply a capacity comparison technique to obtain a sufficient condition for the submanifolds to be parabolic, i...

Extrinsic morphology of graphene

International Nuclear Information System (INIS)

Li, Teng

2011-01-01

Graphene is intrinsically non-flat and corrugates randomly. Since the corrugating physics of atomically thin graphene is strongly tied to its electronics properties, randomly corrugating morphology of graphene poses a significant challenge to its application in nanoelectronic devices for which precise (digital) control is the key. Recent studies revealed that the morphology of substrate-supported graphene is regulated by the graphene–substrate interaction, thus is distinct from the random intrinsic morphology of freestanding graphene. The regulated extrinsic morphology of graphene sheds light on new pathways to fine tune the properties of graphene. To guide further research to explore these fertile opportunities, this paper reviews recent progress on modeling and experimental studies of the extrinsic morphology of graphene under a wide range of external regulation, including two-dimensional and one-dimensional substrate surface features and one-dimensional and zero-dimensional nanoscale scaffolds (e.g. nanowires and nanoparticles)

Development of the intrinsic and extrinsic innervation of the gut.

Science.gov (United States)

Uesaka, Toshihiro; Young, Heather M; Pachnis, Vassilis; Enomoto, Hideki

2016-09-15

The gastrointestinal (GI) tract is innervated by intrinsic enteric neurons and by extrinsic efferent and afferent nerves. The enteric (intrinsic) nervous system (ENS) in most regions of the gut consists of two main ganglionated layers; myenteric and submucosal ganglia, containing numerous types of enteric neurons and glial cells. Axons arising from the ENS and from extrinsic neurons innervate most layers of the gut wall and regulate many gut functions. The majority of ENS cells are derived from vagal neural crest cells (NCCs), which proliferate, colonize the entire gut, and first populate the myenteric region. After gut colonization by vagal NCCs, the extrinsic nerve fibers reach the GI tract, and Schwann cell precursors (SCPs) enter the gut along the extrinsic nerves. Furthermore, a subpopulation of cells in myenteric ganglia undergoes a radial (inward) migration to form the submucosal plexus, and the intrinsic and extrinsic innervation to the mucosal region develops. Here, we focus on recent progress in understanding the developmental processes that occur after the gut is colonized by vagal ENS precursors, and provide an up-to-date overview of molecular mechanisms regulating the development of the intrinsic and extrinsic innervation of the GI tract. Copyright © 2016 Elsevier Inc. All rights reserved.

A novel hyper-viscoelastic model for consolidation of toughened prepregs under processing conditions

OpenAIRE

Belnoue, J.P.-H.; Nixon-Pearson, O.J.; Ivanov, D.; Hallett, S.R.

2016-01-01

The paper presents a new modelling concept for describing the compressibility of toughened uncured prepregs over a wide range of processing conditions (i.e. automatic fibre deposition, hot debulking and pre-curing consolidation). The primary challenge of the work is to simulate the material response due complex flow and deformation mechanisms. This generation of prepreg systems exhibits both percolation (bleeding) flow typical for conventional thermosets, where the pressure gradient causes re...

Supply chain management in Forest products industry-case study for S?dra Cell Company

Institute of Scientific and Technical Information of China (English)

YAO; PAN

2016-01-01

The supply chain plays an increasing significant role in current global business operation process.It is not just considered as a crucial factor for leading the company to achieve their strategic goals,but also assisting firm’s to enhance the competitiveness in its own industry.This report choses the Swedish forest company-S?dra Cell as a case company to analysis its supply chain management advantages and disadvantages. It also states the role of supply chain management theory in assisting organization to achieve its strategic goal and marketing strategies.

Emotion impairs extrinsic source memory--An ERP study.

Science.gov (United States)

Mao, Xinrui; You, Yuqi; Li, Wen; Guo, Chunyan

2015-09-01

Substantial advancements in understanding emotional modulation of item memory notwithstanding, controversies remain as to how emotion influences source memory. Using an emotional extrinsic source memory paradigm combined with remember/know judgments and two key event-related potentials (ERPs)-the FN400 (a frontal potential at 300-500 ms related to familiarity) and the LPC (a later parietal potential at 500-700 ms related to recollection), our research investigated the impact of emotion on extrinsic source memory and the underlying processes. We varied a semantic prompt (either "people" or "scene") preceding a study item to manipulate the extrinsic source. Behavioral data indicated a significant effect of emotion on "remember" responses to extrinsic source details, suggesting impaired recollection-based source memory in emotional (both positive and negative) relative to neutral conditions. In parallel, differential FN400 and LPC amplitudes (correctly remembered - incorrectly remembered sources) revealed emotion-related interference, suggesting impaired familiarity and recollection memory of extrinsic sources associated with positive or negative items. These findings thus lend support to the notion of emotion-induced memory trade off: while enhancing memory of central items and intrinsic/integral source details, emotion nevertheless disrupts memory of peripheral contextual details, potentially impairing both familiarity and recollection. Importantly, that positive and negative items result in comparable memory impairment suggests that arousal (vs. affective valence) plays a critical role in modulating dynamic interactions among automatic and elaborate processes involved in memory. Copyright © 2015 Elsevier B.V. All rights reserved.

The detrimental effects of extrinsic reinforcement on "Intrinsic motivation".

Science.gov (United States)

Dickinson, A M

1989-01-01

Extrinsic consequences have been criticized on the grounds that they decrease intrinsic motivation or internally initiated behavior. Two popular rationales for this criticism, Lepper's overjustification hypothesis (1981) and Deci's motivational theory (Deci & Ryan, 1985), are reviewed and the criticism is then redefined behaviorally. "Intrinsically controlled" behavior is defined as behavior maintained by response-produced reinforcers, and the question concerning extrinsic consequences is thus restated as follows: When behavior is maintained by response-produced stimuli, does extrinsic reinforcement decrease the reinforcing value of those stimuli? The empirical support for this detrimental effect is summarized briefly, and several possible explanations for the phenomenon are offered. Research results that reflect on the effect's generality and social significance are discussed next, with the conclusion that the effect is transient and not likely to occur at all if extrinsic rewards are reinforcing, noncompetitive, based on reasonable performance standards, and delivered repetitively.

Computational model of spalling and effective fibers on toughening in fiber reinforced composites at an early stage of crack formation

Directory of Open Access Journals (Sweden)

Chong Wang

Full Text Available This work suggests a computational model that takes account of effective fibers on toughening in FRC at an early stage of crack formation. We derived the distribution of pressure provoked by a random inclined fiber in the matrix and calculated stresses through integrating the pressure and tangent stress along the fiber/matrix interface with the Kelvin's fundamental solution and the Mindlin's complementary solution. The evolution of spalling in the matrix was traced. The percentages of effective fibers were evaluated with variations in strength, interface resistance, diameter and elasticity modulus. The main conclusion is that low elasticity modulus combined high strength of fibers raises dramatically the effective fibers, which would benefit toughening.

Data on a Laves phase intermetallic matrix composite in situ toughened by ductile precipitates.

Science.gov (United States)

Knowles, Alexander J; Bhowmik, Ayan; Purkayastha, Surajit; Jones, Nicholas G; Giuliani, Finn; Clegg, William J; Dye, David; Stone, Howard J

2017-10-01

The data presented in this article are related to the research article entitled "Laves phase intermetallic matrix composite in situ toughened by ductile precipitates" (Knowles et al.) [1]. The composite comprised a Fe 2 (Mo, Ti) matrix with bcc (Mo, Ti) precipitated laths produced in situ by an aging heat treatment, which was shown to confer a toughening effect (Knowles et al.) [1]. Here, details are given on a focused ion beam (FIB) slice and view experiment performed on the composite so as to determine that the 3D morphology of the bcc (Mo, Ti) precipitates were laths rather than needles. Scanning transmission electron microscopy (S(TEM)) micrographs of the microstructure as well as energy dispersive X-ray spectroscopy (EDX) maps are presented that identify the elemental partitioning between the C14 Laves matrix and the bcc laths, with Mo rejected from the matrix into laths. A TEM selected area diffraction pattern (SADP) and key is provided that was used to validate the orientation relation between the matrix and laths identified in (Knowles et al.) [1] along with details of the transformation matrix determined.

Data on a Laves phase intermetallic matrix composite in situ toughened by ductile precipitates

Directory of Open Access Journals (Sweden)

Alexander J. Knowles

2017-10-01

Full Text Available The data presented in this article are related to the research article entitled “Laves phase intermetallic matrix composite in situ toughened by ductile precipitates” (Knowles et al. [1]. The composite comprised a Fe2(Mo, Ti matrix with bcc (Mo, Ti precipitated laths produced in situ by an aging heat treatment, which was shown to confer a toughening effect (Knowles et al. [1]. Here, details are given on a focused ion beam (FIB slice and view experiment performed on the composite so as to determine that the 3D morphology of the bcc (Mo, Ti precipitates were laths rather than needles. Scanning transmission electron microscopy (S(TEM micrographs of the microstructure as well as energy dispersive X-ray spectroscopy (EDX maps are presented that identify the elemental partitioning between the C14 Laves matrix and the bcc laths, with Mo rejected from the matrix into laths. A TEM selected area diffraction pattern (SADP and key is provided that was used to validate the orientation relation between the matrix and laths identified in (Knowles et al. [1] along with details of the transformation matrix determined.

INTRINSIC AND EXTRINSIC MOTIVATION - AN INVESTIGATION OF PERFORMANCE CORRELATION

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Abrudan Maria-Madela

2011-07-01

Full Text Available A series of research untaken in the last decade have revealed some interesting aspects regarding the effects of different types of motivation on performance. Among the researchers who have shown interest in this field we can number: Richard Ryan, Edward Deci, Sam Glucksberg, Dan Ariely, Robert Eisenhower, Linda Shanock, analysts from London School of Economics, and others. Their findings suggest that extrinsic incentives may have a negative impact on overall performance, but a general agreement in this respect has not been reached. In this paper we intend to shed some light upon the relationship between intrinsic and extrinsic motivation and performance. Experts define intrinsic motivation as being the execution of a task or activity because of the inherent satisfaction arising from it rather than due to some separate outcome. In contrast with intrinsic motivation, we speak of extrinsic motivation whenever an activity is done in order to attain some separable outcome. With the purpose of contributing to the clarification of the links between concepts, we initiated and conducted an explanatory research. The research is based on the analysis of the relations between the results obtained by third year students and their predominant type of motivation. For this, we formulated and tested four work hypotheses using a combination of quantitative methods (investigation and qualitative methods (focus group. After the validation of the questionnaires, the respondents were divided into four categories: intrinsically motivated, extrinsically motivated, both intrinsically and extrinsically motivated and unmotivated. To analyze the collected data, we made use of Excel and SPSS. Some of the primary conclusions of the research are as follows: as the average increases, the percent of individuals having both extrinsic and intrinsic motivation is decreasing; the highest percentage of unmotivated students is concentrated in the highest average category; Female

Quantifying intrinsic and extrinsic variability in stochastic gene expression models.

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Singh, Abhyudai; Soltani, Mohammad

2013-01-01

Genetically identical cell populations exhibit considerable intercellular variation in the level of a given protein or mRNA. Both intrinsic and extrinsic sources of noise drive this variability in gene expression. More specifically, extrinsic noise is the expression variability that arises from cell-to-cell differences in cell-specific factors such as enzyme levels, cell size and cell cycle stage. In contrast, intrinsic noise is the expression variability that is not accounted for by extrinsic noise, and typically arises from the inherent stochastic nature of biochemical processes. Two-color reporter experiments are employed to decompose expression variability into its intrinsic and extrinsic noise components. Analytical formulas for intrinsic and extrinsic noise are derived for a class of stochastic gene expression models, where variations in cell-specific factors cause fluctuations in model parameters, in particular, transcription and/or translation rate fluctuations. Assuming mRNA production occurs in random bursts, transcription rate is represented by either the burst frequency (how often the bursts occur) or the burst size (number of mRNAs produced in each burst). Our analysis shows that fluctuations in the transcription burst frequency enhance extrinsic noise but do not affect the intrinsic noise. On the contrary, fluctuations in the transcription burst size or mRNA translation rate dramatically increase both intrinsic and extrinsic noise components. Interestingly, simultaneous fluctuations in transcription and translation rates arising from randomness in ATP abundance can decrease intrinsic noise measured in a two-color reporter assay. Finally, we discuss how these formulas can be combined with single-cell gene expression data from two-color reporter experiments for estimating model parameters.

Does Extrinsic Goal Framing Enhance Extrinsic Goal-Oriented Individuals' Learning and Performance? An Experimental Test of the Match Perspective versus Self-Determination Theory

Science.gov (United States)

Vansteenkiste, Maarten; Timmermans, Tinneke; Lens, Willy; Soenens, Bart; Van den Broeck, Anja

2008-01-01

Previous work within self-determination theory has shown that experimentally framing a learning activity in terms of extrinsic rather than intrinsic goals results in poorer conceptual learning and performance, presumably because extrinsic goal framing detracts attention from the learning activity and is less directly satisfying of basic…

Intrinsic and Extrinsic Motivation for Stereotypic and Repetitive Behavior

Science.gov (United States)

Joosten, Annette V.; Bundy, Anita C.; Einfeld, Stewart L.

2009-01-01

This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess…

Adaptive molecular evolution of the Major Histocompatibility Complex genes, DRA and DQA, in the genus Equus.

Science.gov (United States)

Kamath, Pauline L; Getz, Wayne M

2011-05-18

Major Histocompatibility Complex (MHC) genes are central to vertebrate immune response and are believed to be under balancing selection by pathogens. This hypothesis has been supported by observations of extremely high polymorphism, elevated nonsynonymous to synonymous base pair substitution rates and trans-species polymorphisms at these loci. In equids, the organization and variability of this gene family has been described, however the full extent of diversity and selection is unknown. As selection is not expected to act uniformly on a functional gene, maximum likelihood codon-based models of selection that allow heterogeneity in selection across codon positions can be valuable for examining MHC gene evolution and the molecular basis for species adaptations. We investigated the evolution of two class II MHC genes of the Equine Lymphocyte Antigen (ELA), DRA and DQA, in the genus Equus with the addition of novel alleles identified in plains zebra (E. quagga, formerly E. burchelli). We found that both genes exhibited a high degree of polymorphism and inter-specific sharing of allele lineages. To our knowledge, DRA allelic diversity was discovered to be higher than has ever been observed in vertebrates. Evidence was also found to support a duplication of the DQA locus. Selection analyses, evaluated in terms of relative rates of nonsynonymous to synonymous mutations (dN/dS) averaged over the gene region, indicated that the majority of codon sites were conserved and under purifying selection (dN

Adaptive molecular evolution of the Major Histocompatibility Complex genes, DRA and DQA, in the genus Equus

Directory of Open Access Journals (Sweden)

Getz Wayne M

2011-05-01

Full Text Available Abstract Background Major Histocompatibility Complex (MHC genes are central to vertebrate immune response and are believed to be under balancing selection by pathogens. This hypothesis has been supported by observations of extremely high polymorphism, elevated nonsynonymous to synonymous base pair substitution rates and trans-species polymorphisms at these loci. In equids, the organization and variability of this gene family has been described, however the full extent of diversity and selection is unknown. As selection is not expected to act uniformly on a functional gene, maximum likelihood codon-based models of selection that allow heterogeneity in selection across codon positions can be valuable for examining MHC gene evolution and the molecular basis for species adaptations. Results We investigated the evolution of two class II MHC genes of the Equine Lymphocyte Antigen (ELA, DRA and DQA, in the genus Equus with the addition of novel alleles identified in plains zebra (E. quagga, formerly E. burchelli. We found that both genes exhibited a high degree of polymorphism and inter-specific sharing of allele lineages. To our knowledge, DRA allelic diversity was discovered to be higher than has ever been observed in vertebrates. Evidence was also found to support a duplication of the DQA locus. Selection analyses, evaluated in terms of relative rates of nonsynonymous to synonymous mutations (dN/dS averaged over the gene region, indicated that the majority of codon sites were conserved and under purifying selection (dN dS. However, the most likely evolutionary codon models allowed for variable rates of selection across codon sites at both loci and, at the DQA, supported the hypothesis of positive selection acting on specific sites. Conclusions Observations of elevated genetic diversity and trans-species polymorphisms supported the conclusion that balancing selection may be acting on these loci. Furthermore, at the DQA, positive selection was

Extrinsic and intrinsic regulation of axon regeneration at a crossroads.

Science.gov (United States)

Kaplan, Andrew; Ong Tone, Stephan; Fournier, Alyson E

2015-01-01

Repair of the injured spinal cord is a major challenge in medicine. The limited intrinsic regenerative response mounted by adult central nervous system (CNS) neurons is further hampered by astrogliosis, myelin debris and scar tissue that characterize the damaged CNS. Improved axon regeneration and recovery can be elicited by targeting extrinsic factors as well as by boosting neuron-intrinsic growth regulators. Our knowledge of the molecular basis of intrinsic and extrinsic regulators of regeneration has expanded rapidly, resulting in promising new targets to promote repair. Intriguingly certain neuron-intrinsic growth regulators are emerging as promising targets to both stimulate growth and relieve extrinsic inhibition of regeneration. This crossroads between the intrinsic and extrinsic aspects of spinal cord injury is a promising target for effective therapies for this unmet need.

Intrinsic and Extrinsic Motivations: Classic Definitions and New Directions.

Science.gov (United States)

Ryan; Deci

2000-01-01

Intrinsic and extrinsic types of motivation have been widely studied, and the distinction between them has shed important light on both developmental and educational practices. In this review we revisit the classic definitions of intrinsic and extrinsic motivation in light of contemporary research and theory. Intrinsic motivation remains an important construct, reflecting the natural human propensity to learn and assimilate. However, extrinsic motivation is argued to vary considerably in its relative autonomy and thus can either reflect external control or true self-regulation. The relations of both classes of motives to basic human needs for autonomy, competence and relatedness are discussed. Copyright 2000 Academic Press.

Sub-10-micrometer toughening and crack tip toughness of dental enamel.

Science.gov (United States)

Ang, Siang Fung; Schulz, Anja; Pacher Fernandes, Rodrigo; Schneider, Gerold A

2011-04-01

In previous studies, enamel showed indications to occlude small cracks in-vivo and exhibited R-curve behaviors for bigger cracks ex-vivo. This study quantifies the crack tip's toughness (K(I0),K(III0)), the crack's closure stress and the cohesive zone size at the crack tip of enamel and investigates the toughening mechanisms near the crack tip down to the length scale of a single enamel crystallite. The crack-opening-displacement (COD) profile of cracks induced by Vickers indents on mature bovine enamel was studied using atomic force microscopy (AFM). The mode I crack tip toughness K(I0) of cracks along enamel rod boundaries and across enamel rods exhibit a similar range of values: K(I0,Ir)=0.5-1.6MPa m(0.5) (based on Irwin's 'near-field' solution) and K(I0,cz)=0.8-1.5MPa m(0.5) (based on the cohesive zone solution of the Dugdale-Muskhelishvili (DM) crack model). The mode III crack tip toughness K(III0,Ir) was computed as 0.02-0.15MPa m(0.5). The crack-closure stress at the crack tip was computed as 163-770 MPa with a cohesive zone length and width 1.6-10.1μm and 24-44 nm utilizing the cohesive zone solution. Toughening elements were observed under AFM and SEM: crack bridging due to protein ligament and hydroxyapatite fibres (micro- and nanometer scale) as well as microcracks were identified. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

Binding of intrinsic and extrinsic features in working memory.

Science.gov (United States)

Ecker, Ullrich K H; Maybery, Murray; Zimmer, Hubert D

2013-02-01

There is ongoing debate concerning the mechanisms of feature binding in working memory. In particular, there is controversy regarding the extent to which these binding processes are automatic. The present article demonstrates that binding mechanisms differ depending on whether the to-be-integrated features are perceived as forming a coherent object. We presented a series of experiments that investigated the binding of color and shape, whereby color was either an intrinsic feature of the shape or an extrinsic feature of the shape's background. Results show that intrinsic color affected shape recognition, even when it was incidentally studied and irrelevant for the recognition task. In contrast, extrinsic color did not affect shape recognition, even when the association of color and shape was encoded and retrievable on demand. This strongly suggests that binding of intrinsic intra-item information but not extrinsic contextual information is obligatory in visual working memory. We highlight links to perception as well as implicit and explicit long-term memory, which suggest that the intrinsic-extrinsic dimension is a principle relevant to multiple domains of human cognition. 2013 APA, all rights reserved

Zirconia toughened SiC whisker reinforced alumina composites small business innovation research

Science.gov (United States)

Loutfy, R. O.; Stuffle, K. L.; Withers, J. C.; Lee, C. T.

1987-01-01

The objective of this phase 1 project was to develop a ceramic composite with superior fracture toughness and high strength, based on combining two toughness inducing materials: zirconia for transformation toughening and SiC whiskers for reinforcement, in a controlled microstructure alumina matrix. The controlled matrix microstructure is obtained by controlling the nucleation frequency of the alumina gel with seeds (submicron alpha-alumina). The results demonstrate the technical feasibility of producing superior binary composites (Al2O3-ZrO2) and tertiary composites (Al2O3-ZrO2-SiC). Thirty-two composites were prepared, consolidated, and fracture toughness tested. Statistical analysis of the results showed that: (1) the SiC type is the key statistically significant factor for increased toughness; (2) sol-gel processing with a-alumina seed had a statistically significant effect on increasing toughness of the binary and tertiary composites compared to the corresponding mixed powder processing; and (3) ZrO2 content within the range investigated had a minor effect. Binary composites with an average critical fracture toughness of 6.6MPam sup 1/2, were obtained. Tertiary composites with critical fracture toughness in the range of 9.3 to 10.1 MPam sup 1/2 were obtained. Results indicate that these composites are superior to zirconia toughened alumina and SiC whisker reinforced alumina ceramic composites produced by conventional techniques with similar composition from published data.

Bridge toughening enhancement in double-notched MoSi2/Nb model composites

International Nuclear Information System (INIS)

Pickard, S.M.; Ghosh, A.K.

1996-01-01

Single-ply composites containing both laminate and continuous Nb fiber reinforcement coated with Al 2 O 3 debond coatings in an MoSi 2 matrix are used as model systems for investigating bridge toughening concepts for various precrack configurations., When cracks are introduced symmetrically on either side of the ductile phase with zero crack offset spacing (S = 0), a minimum amount of energy is expended in plastic deformation and the local rupture process in the metal, as measured by the area of the force displacement curve in tension. For asymmetric precracks introduced on either side of the ductile reinforcement, as the offset spacing, S, was varied from 1 to 20 R (R being the ductile phase half-thickness), the overall extension continuously increased within the bridging ligament. The effective ligament gage length was nearly equal to the crack spacing in the limiting case of a weak interface. However, the ductile Nb phase developed a Nb 5 Si 3 reaction layer on its surface which was strongly bonded to the Nb and was found to undergo periodic cracking, leading to numerous shear bands within the ductile phase. This unique and previously unreported mode of metal deformation in shear loading has been analyzed using a simple geometric model. The results indicate that the profusion of shear bands is the primary source of toughening enhancement in the case of asymmetric crack geometry, which was not recognized in prior work of this type

Integrated Ternary Bioinspired Nanocomposites via Synergistic Toughening of Reduced Graphene Oxide and Double-Walled Carbon Nanotubes.

Science.gov (United States)

Gong, Shanshan; Cui, Wei; Zhang, Qi; Cao, Anyuan; Jiang, Lei; Cheng, Qunfeng

2015-12-22

With its synergistic toughening effect and hierarchical micro/nanoscale structure, natural nacre sets a "gold standard" for nacre-inspired materials with integrated high strength and toughness. We demonstrated strong and tough ternary bioinspired nanocomposites through synergistic toughening of reduced graphene oxide and double-walled carbon nanotube (DWNT) and covalent bonding. The tensile strength and toughness of this kind of ternary bioinspired nanocomposites reaches 374.1 ± 22.8 MPa and 9.2 ± 0.8 MJ/m(3), which is 2.6 and 3.3 times that of pure reduced graphene oxide film, respectively. Furthermore, this ternary bioinspired nanocomposite has a high conductivity of 394.0 ± 6.8 S/cm and also shows excellent fatigue-resistant properties, which may enable this material to be used in aerospace, flexible energy devices, and artificial muscle. The synergistic building blocks with covalent bonding for constructing ternary bioinspired nanocomposites can serve as the basis of a strategy for the construction of integrated, high-performance, reduced graphene oxide (rGO)-based nanocomposites in the future.

Recollection and unitization in associating actors with extrinsic and intrinsic motions.

Science.gov (United States)

Kersten, Alan W; Earles, Julie L; Berger, Johanna D

2015-04-01

Four experiments provide evidence for a distinction between 2 different kinds of motion representations. Extrinsic motions involve the path of an object with respect to an external frame of reference. Intrinsic motions involve the relative motions of the parts of an object. This research suggests that intrinsic motions are represented conjointly with information about the identities of the actors who perform them, whereas extrinsic motions are represented separately from identity information. Experiment 1 demonstrated that participants remembered which actor had performed a particular intrinsic motion better than they remembered which actor had performed a particular extrinsic motion. Experiment 2 replicated this effect with incidental encoding of actor information, suggesting that encoding intrinsic motions leads one to automatically encode identity information. The results of Experiments 3 and 4 were fit by Yonelinas's (1999) source-memory model to quantify the contributions of familiarity and recollection to memory for the actors who carried out the intrinsic and extrinsic motions. Successful performance with extrinsic motion items in Experiment 3 required participants to remember in which scene contexts an actor had appeared, whereas successful performance in Experiment 4 required participants to remember the exact path taken by an actor in each scene. In both experiments, discrimination of old and new combinations of actors and extrinsic motions relied strongly on recollection, suggesting independent but associated representations of actors and extrinsic motions. In contrast, participants discriminated old and new combinations of actors and intrinsic motions primarily on the basis of familiarity, suggesting unitized representations of actors and intrinsic motions. (c) 2015 APA, all rights reserved).

Intrinsic-extrinsic factors in sport motivation.

Science.gov (United States)

Pedersen, Darhl M

2002-10-01

Participants were 83 students (36 men and 47 women). 10 intrinsic-extrinsic factors involved in sport motivation were obtained. The factors were generated from items obtained from the participants rather than items from the experimenter. This was done to avoid the possible influence of preconceptions on the part of the experimenter regarding what the final dimensions may be. Obtained motivational factors were Social Reinforcement, Fringe Benefits, Fame and Fortune, External Forces, Proving Oneself, Social Benefits, Mental Enrichment, Expression of Self, Sense of Accomplishment, and Self-enhancement. Each factor was referred to an intrinsic-extrinsic dimension to describe its relative position on that dimension. The order of the factors as listed indicates increasing intrinsic motivation. i.e., the first four factors were rated in the extrinsic range, whereas the remaining six were rated to be in the intrinsic range. Next, the participants rated the extent to which each of the various factors was involved in their decision to participate in sport activities. The pattern of use of the motivational factors was the same for both sexes except that men indicated greater use of the Fringe Benefits factor. Overall, the more intrinsic a sport motivation factor was rated, the more likely it was to be rated as a factor in actual sport participation.

The detrimental effects of extrinsic reinforcement on “Intrinsic motivation”

Science.gov (United States)

Dickinson, Alyce M.

1989-01-01

Extrinsic consequences have been criticized on the grounds that they decrease intrinsic motivation or internally initiated behavior. Two popular rationales for this criticism, Lepper's overjustification hypothesis (1981) and Deci's motivational theory (Deci & Ryan, 1985), are reviewed and the criticism is then redefined behaviorally. “Intrinsically controlled” behavior is defined as behavior maintained by response-produced reinforcers, and the question concerning extrinsic consequences is thus restated as follows: When behavior is maintained by response-produced stimuli, does extrinsic reinforcement decrease the reinforcing value of those stimuli? The empirical support for this detrimental effect is summarized briefly, and several possible explanations for the phenomenon are offered. Research results that reflect on the effect's generality and social significance are discussed next, with the conclusion that the effect is transient and not likely to occur at all if extrinsic rewards are reinforcing, noncompetitive, based on reasonable performance standards, and delivered repetitively. PMID:22478013

Study of the toughening mechanisms in bone and biomimetic hydroxyapatite materials using Raman microprobe spectroscopy.

Science.gov (United States)

Pezzotti, Giuseppe; Sakakura, Seiji

2003-05-01

A Raman microprobe spectroscopy characterization of microscopic fracture mechanisms is presented for a natural hydroxyapatite material (cortical bovine femur) and two synthetic hydroxyapatite-based materials with biomimetic structures-a hydroxyapatite skeleton interpenetrated with a metallic (silver) or a polymeric (nylon-6) phase. In both the natural and synthetic materials, a conspicuous amount of toughening arose from a microscopic crack-bridging mechanism operated by elasto-plastic stretching of unbroken second-phase ligaments along the crack wake. This mechanism led to a rising R-curve behavior. An additional micromechanism, responsible for stress relaxation at the crack tip, was recognized in the natural bone material and was partly mimicked in the hydroxyapatite/silver composite. This crack-tip mechanism conspicuously enhanced the cortical bone material resistance to fracture initiation. A piezo-spectroscopic technique, based on a microprobe measurement of 980 cm(-1) Raman line of hydroxyapatite, enabled us to quantitatively assess in situ the microscopic stress fields developed during fracture both at the crack tip and along the crack wake. Using the Raman piezo-spectroscopy technique, toughening mechanisms were assessed quantitatively and rationally related to the macroscopic fracture characteristics of hydroxyapatite-based materials. Copyright 2003 Wiley Periodicals, Inc.

Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials

Science.gov (United States)

Keith, Theo G.

2005-01-01

The purpose of this report is to provide a final report for the period of 12/1/03 through 11/30/04 for NASA Cooperative Agreement NCC3-776, entitled "Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials." During this final period, major efforts were focused on both the determination of mechanical properties of advanced ceramic materials and the development of mechanical test methodologies under several different programs of the NASA-Glenn. The important research activities made during this period are: 1. Mechanical properties evaluation of two gas-turbine grade silicon nitrides. 2) Mechanical testing for fuel-cell seal materials. 3) Mechanical properties evaluation of thermal barrier coatings and CFCCs and 4) Foreign object damage (FOD) testing.

Extrinsic passivation of silicon surfaces for solar cells

OpenAIRE

Bonilla, R.S.; Reichel, C.; Hermle, M.; Martins, G.; Wilshaw, P.R.

2015-01-01

In the present work we study the extent to which extrinsic chemical and field effect passivation can improve the overall electrical passivation quality of silicon dioxide on silicon. Here we demonstrate that, when optimally applied, extrinsic passivation can produce surface recombination velocities below 1.2 cm/s in planar 1 Omega cm n-type Si. This is largely due to the additional field effect passivation component which reduces the recombination velocity below 2.13 cm/s. On textured surface...

On intrinsic and extrinsic origin of plasmon peaks

International Nuclear Information System (INIS)

Takayama, Shoichi; Kawai, Jun

2008-01-01

The origin of the plasmon loss peaks in X-ray photoelectron spectra are discussed based on the (1) intrinsic, (2) extrinsic, (3) quantum interference between (1) and (2), and (4) mixture of (1) and (2). It was believed that the major part of plasmon was due to the extrinsic, the present analysis concludes the major part is intrinsic, depending the excitation energy. This analysis is based on the electron reflection spectra, but valid for X-ray photoelectron spectra. (author)

Morphological Study on Room-Temperature-Cured PMMA-Grafted Natural Rubber-Toughened Epoxy/Layered Silicate Nanocomposite

OpenAIRE

Yuhana, N. Y.; Ahmad, S.; Kamal, M. R.; Jana, S. C.; Bahri, A. R. Shamsul

2012-01-01

A morphological study was conducted on ternary systems containing epoxy, PMMA-grafted natural rubber, and organic chemically modified montmorillonite (Cloisite 30B). Optical microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and wide-angle X-ray diffraction (WAXD) analysis were used. The following four materials were prepared at room temperature: cured unmodified epoxy, cured toughened epoxy, cured unmodified epoxy/Cloisite 3...

A reduced covariant string model for the extrinsic string

International Nuclear Information System (INIS)

Botelho, L.C.L.

1989-01-01

It is studied a reduced covariant string model for the extrinsic string by using Polyakov's path integral formalism. On the basis of this reduced model it is suggested that the extrinsic string has its critical dimension given by 13. Additionally, it is calculated in a simple way Poliakov's renormalization group law for the string rigidity coupling constants. (A.C.A.S.) [pt

Intrinsic and extrinsic motivation for stereotypic and repetitive behavior.

Science.gov (United States)

Joosten, Annette V; Bundy, Anita C; Einfeld, Stewart L

2009-03-01

This study provides evidence for intrinsic and extrinsic motivators for stereotypical and repetitive behavior in children with autism and intellectual disability and children with intellectual disability alone. We modified the Motivation Assessment Scale (MAS) (1988b); dividing it into intrinsic and extrinsic measures and adding items to assess anxiety as an intrinsic motivator. Rasch analysis of data from 279 MASs (74 children) revealed that the items formed two unidimensional scales. Anxiety was a more likely intrinsic motivator than sensory seeking for children with dual diagnoses; the reverse was true for children with intellectual disability only. Escape and gaining a tangible object were the most common extrinsic motivators for those with dual diagnoses and attention and escape for children with intellectual disability.

A prototype empirical framework of intrinsic and extrinsic EERQI indicators

NARCIS (Netherlands)

Mooij, Ton

2012-01-01

The research question is: What do statistical analyses show us about the relationships between intrinsic and extrinsic indicators of quality and what does this mean when constructing a prototype EERQI framework? The pilot study involved the scoring on both intrinsic and extrinsic indica-tors for 177

Test Review: Beaver, J. M., & Carter, M. A. (2006). "The Developmental Reading Assessment--Second Edition" (DRA2). Upper Saddle River, NJ--Pearson

Science.gov (United States)

McCarty, Allison M.; Christ, Theodore J.

2010-01-01

This article reviews the "Developmental Reading Assessment--Second Edition" (DRA2), a teacher-administered assessment that identifies students' instructional level, along with their strengths and weaknesses in reading. Once teachers calculate and interpret scores, the data can purportedly be used to inform, and possibly individualize,…

Distinct molecular signatures of mild extrinsic and intrinsic atopic dermatitis.

Science.gov (United States)

Martel, Britta C; Litman, Thomas; Hald, Andreas; Norsgaard, Hanne; Lovato, Paola; Dyring-Andersen, Beatrice; Skov, Lone; Thestrup-Pedersen, Kristian; Skov, Søren; Skak, Kresten; Poulsen, Lars K

2016-06-01

Atopic dermatitis (AD) is a common inflammatory skin disease with underlying defects in epidermal function and immune responses. In this study, we used microarray analysis to investigate differences in gene expression in lesional skin from patients with mild extrinsic or intrinsic AD compared to skin from healthy controls and from lesional psoriasis skin. The primary aim was to identify differentially expressed genes involved in skin barrier formation and inflammation, and to compare our results with those reported for patients with moderate and severe AD. In contrast to severe AD, expression of the majority of genes associated with skin barrier formation was unchanged or upregulated in patients with mild AD compared to normal healthy skin. Among these, no significant differences in the expression of filaggrin (FLG) and loricrin at both mRNA and protein level were found in lesional skin from patients with mild AD, despite the presence of heterozygous FLG mutations in the majority of patients with mild extrinsic AD. Several inflammation-associated genes such as S100A9, MMP12, CXCL10 and CCL18 were highly expressed in lesional skin from patients with mild psoriasis and were also increased in patients with mild extrinsic and intrinsic AD similar to previous reports for severe AD. Interestingly, expression of genes involved in inflammatory responses in intrinsic AD resembled that of psoriasis more than that of extrinsic AD. Overall, differences in expression of inflammation-associated genes found among patients with mild intrinsic and extrinsic AD correlated with previous findings for patients with severe intrinsic and extrinsic AD. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Advanced tungsten materials for plasma-facing components of DEMO and fusion power plants

International Nuclear Information System (INIS)

Neu, R.; Riesch, J.; Coenen, J.W.; Brinkmann, J.; Calvo, A.; Elgeti, S.; García-Rosales, C.; Greuner, H.; Hoeschen, T.; Holzner, G.; Klein, F.; Koch, F.

2016-01-01

Highlights: • Development of W-fibre enhanced W-composites incorporating extrinsic toughening mechanisms. • Production of a large sample (more than 2000 long fibres) for mechanical and thermal testing. • Even in a fully embrittled state, toughening mechanisms are still effective. • Emissions of volatile W-oxides can be suppressed by alloying W with elements forming stable oxides. • WCr10Ti2 has been successfully tested under accidental conditions and high heat fluxes. - Abstract: Tungsten is the major candidate material for the armour of plasma facing components in future fusion devices. To overcome the intrinsic brittleness of tungsten, which strongly limits its operational window, a W-fibre enhanced W-composite material (W_f/W) has been developed incorporating extrinsic toughening mechanisms. Small W_f/W samples show a large increase in toughness. Recently, a large sample (50 mm × 50 mm × 3 mm) with more than 2000 long fibres has been successfully produced allowing further mechanical and thermal testing. It could be shown that even in a fully embrittled state, toughening mechanisms as crack bridging by intact fibres, as well as the energy dissipation by fibre-matrix interface debonding and crack deflection are still effective. A potential problem with the use of pure W in a fusion reactor is the formation of radioactive and highly volatile WO_3 compounds and their potential release under accidental conditions. It has been shown that the oxidation of W can be strongly suppressed by alloying with elements forming stable oxides. WCr10Ti2 alloy has been produced on a technical scale and has been successfully tested in the high heat flux test facility GLADIS. Recently, W-Cr-Y alloys have been produced on a lab-scale. They seem to have even improved properties compared to the previously investigated W alloys.

Advanced tungsten materials for plasma-facing components of DEMO and fusion power plants

Energy Technology Data Exchange (ETDEWEB)

Neu, R., E-mail: Rudolf.Neu@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); Fakultät für Maschinenbau, Technische Universität München, D-85748 Garching (Germany); Riesch, J. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); Coenen, J.W. [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung – Plasmaphysik, D-52425 Jülich (Germany); Brinkmann, J. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung – Plasmaphysik, D-52425 Jülich (Germany); Calvo, A. [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain); Elgeti, S. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); García-Rosales, C. [CEIT and Tecnun (University of Navarra), E-20018 San Sebastian (Spain); Greuner, H.; Hoeschen, T.; Holzner, G. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); Klein, F. [Forschungszentrum Jülich GmbH, Institut für Energie- und Klimaforschung – Plasmaphysik, D-52425 Jülich (Germany); Koch, F. [Max-Planck-Institut für Plasmaphysik, D-85748 Garching (Germany); and others

2016-11-01

Highlights: • Development of W-fibre enhanced W-composites incorporating extrinsic toughening mechanisms. • Production of a large sample (more than 2000 long fibres) for mechanical and thermal testing. • Even in a fully embrittled state, toughening mechanisms are still effective. • Emissions of volatile W-oxides can be suppressed by alloying W with elements forming stable oxides. • WCr10Ti2 has been successfully tested under accidental conditions and high heat fluxes. - Abstract: Tungsten is the major candidate material for the armour of plasma facing components in future fusion devices. To overcome the intrinsic brittleness of tungsten, which strongly limits its operational window, a W-fibre enhanced W-composite material (W{sub f}/W) has been developed incorporating extrinsic toughening mechanisms. Small W{sub f}/W samples show a large increase in toughness. Recently, a large sample (50 mm × 50 mm × 3 mm) with more than 2000 long fibres has been successfully produced allowing further mechanical and thermal testing. It could be shown that even in a fully embrittled state, toughening mechanisms as crack bridging by intact fibres, as well as the energy dissipation by fibre-matrix interface debonding and crack deflection are still effective. A potential problem with the use of pure W in a fusion reactor is the formation of radioactive and highly volatile WO{sub 3} compounds and their potential release under accidental conditions. It has been shown that the oxidation of W can be strongly suppressed by alloying with elements forming stable oxides. WCr10Ti2 alloy has been produced on a technical scale and has been successfully tested in the high heat flux test facility GLADIS. Recently, W-Cr-Y alloys have been produced on a lab-scale. They seem to have even improved properties compared to the previously investigated W alloys.

Imaging with extrinsic Raman labels

NARCIS (Netherlands)

Sijtsema, N M; Duindam, J J; Puppels, G J; Otto, C; Greve, J

1996-01-01

In two separate examples we demonstrate the use of extrinsic Raman scattering probes for imaging of biological samples. First, the distribution of cholesterol in a rat eye Lens is determined with the use of the Raman scattered light from filipin, a molecule which binds specifically to cholesterol.

Copper absorption from foods labelled intrinsically and extrinsically with Cu-65 stable isotope.

Science.gov (United States)

Harvey, L J; Dainty, J R; Beattie, J H; Majsak-Newman, G; Wharf, S G; Reid, M D; Fairweather-Tait, S J

2005-03-01

To determine copper absorption from copper containing foods labelled either intrinsically or extrinsically with a highly enriched Cu-65 stable isotope label. A longitudinal cross-over study. The study was conducted at the Institute of Food Research, Human Nutrition Unit, Norwich, UK. Subjects were recruited locally via advertisements placed around the Norwich Research Park. A total of 10 volunteers (nine female, one male) took part in the study, but not all volunteers completed each of the test meals. A highly enriched Cu-65 stable isotope label was administered to volunteers in the form of a reference dose or in breakfast test meals consisting of red wine, soya beans, mushrooms or sunflower seeds. Faecal monitoring and mass spectrometry techniques were used to estimate the relative quantities of copper absorbed from the different test meals. True copper absorption from the reference dose (54%) was similar to extrinsically labelled red wine (49%) and intrinsically labelled sunflower seeds (52%), but significantly higher than extrinsically labelled mushrooms (35%), intrinsically (29%) and extrinsically (15%) labelled soya beans and extrinsically labelled sunflower seed (32%) test meals. The use of Cu-65 extrinsic labels in copper absorption studies requires validation according to the food being examined; intrinsic and extrinsic labelling produced significantly different results for sunflower seeds.

Intrinsic and extrinsic spin Hall effects of Dirac electrons

International Nuclear Information System (INIS)

Fukazawa, Takaaki; Kohno, Hiroshi; Fujimoto, Junji

2017-01-01

We investigate the spin Hall effect (SHE) of electrons described by the Dirac equation, which is used as an effective model near the L-points in bismuth. By considering short-range nonmagnetic impurities, we calculate the extrinsic as well as intrinsic contributions on an equal footing. The vertex corrections are taken into account within the ladder type and the so-called skew-scattering type. The intrinsic SHE which we obtain is consistent with that of Fuseya et al. It is found that the extrinsic contribution dominates the intrinsic one when the system is metallic. The extrinsic SHE due to the skew scattering is proportional to Δ/n i u, where 2Δ is the band gap, n i is the impurity concentration, and u is the strength of the impurity potential. (author)

The spinning particle with extrinsic curvature

International Nuclear Information System (INIS)

Dhar, A.

1988-01-01

We construct and analyse an action for the spinning particle which contains an extrinsic curvature term. A possible generalization of this construction to the case of the spinning string is also discussed. (orig.)

Iron-59 absorption from soy hulls: intrinsic vs extrinsic labeling

International Nuclear Information System (INIS)

Lykken, G.I.; Mahalko, J.R.; Nielsen, E.J.; Dintzis, F.R.

1986-01-01

As part of an evaluation of the validity of the extrinsic labeling technique for measuring iron absorption, absorption from soy hulls extrinsically labeled ( 59 Fe added to bread dough) was compared with that from soy hulls intrinsically labeled ( 59 Fe incorporated into the soy plant during growth). Century soybeans were grown in a greenhouse. After pods had formed and were filling, each plant was stem injected twice, at 3 day intervals, with 22 μCi 59 Fe as FeCl 2 in 25 μl of 0.5 M HCl solution. After the plants had senesced, the soybeans were harvested, dried, shelled and the hulls removed. Standard meals containing 3.5 mg Fe/meal and up to 0.06 μCi 59 Fe in a soy hull bun were fed on 2 consecutive days to free-living volunteers in a crossover design. Absorption of 59 Fe was greater from intrinsically labeled soy hulls than from extrinsically labeled soy hulls, 20 +/- 20% vs 15 +/- 11% (n=14, p > 0.05 by paired t-test). Apparent absorption ranged from 1.3% to 77% from intrinsically labeled soy hulls and .5% to 29% from extrinsically labeled soy hulls with the highest absorption occurring in persons with low serum ferritin (S.F. < 8 ng/ml). These findings provide additional evidence that the extrinsic labeling method is a valid measure of iron bioavailability to humans

The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.

Directory of Open Access Journals (Sweden)

Giulio Caravagna

Full Text Available After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii a model of enzymatic futile cycle and (iii a genetic toggle switch. In (ii and (iii we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.

The interplay of intrinsic and extrinsic bounded noises in biomolecular networks.

Science.gov (United States)

Caravagna, Giulio; Mauri, Giancarlo; d'Onofrio, Alberto

2013-01-01

After being considered as a nuisance to be filtered out, it became recently clear that biochemical noise plays a complex role, often fully functional, for a biomolecular network. The influence of intrinsic and extrinsic noises on biomolecular networks has intensively been investigated in last ten years, though contributions on the co-presence of both are sparse. Extrinsic noise is usually modeled as an unbounded white or colored gaussian stochastic process, even though realistic stochastic perturbations are clearly bounded. In this paper we consider Gillespie-like stochastic models of nonlinear networks, i.e. the intrinsic noise, where the model jump rates are affected by colored bounded extrinsic noises synthesized by a suitable biochemical state-dependent Langevin system. These systems are described by a master equation, and a simulation algorithm to analyze them is derived. This new modeling paradigm should enlarge the class of systems amenable at modeling. We investigated the influence of both amplitude and autocorrelation time of a extrinsic Sine-Wiener noise on: (i) the Michaelis-Menten approximation of noisy enzymatic reactions, which we show to be applicable also in co-presence of both intrinsic and extrinsic noise, (ii) a model of enzymatic futile cycle and (iii) a genetic toggle switch. In (ii) and (iii) we show that the presence of a bounded extrinsic noise induces qualitative modifications in the probability densities of the involved chemicals, where new modes emerge, thus suggesting the possible functional role of bounded noises.

Extrinsic response enhancement at the polymorphic phase boundary in piezoelectric materials

Energy Technology Data Exchange (ETDEWEB)

Ochoa, Diego A.; García, José E., E-mail: jose.eduardo.garcia@upc.edu [Department of Physics, Universitat Politècnica de Catalunya - BarcelonaTech, Barcelona 08034 (Spain); Esteves, Giovanni; Jones, Jacob L. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27696 (United States); Rubio-Marcos, Fernando; Fernández, José F. [Department of Electroceramics, Instituto de Cerámica y Vidrio - CSIC, Madrid 28049 (Spain)

2016-04-04

Polymorphic phase boundaries (PPBs) in piezoelectric materials have attracted significant interest in recent years, in particular, because of the unique properties that can be found in their vicinity. However, to fully harness their potential as micro-nanoscale functional entities, it is essential to achieve reliable and precise control of their piezoelectric response, which is due to two contributions known as intrinsic and extrinsic. In this work, we have used a (K,Na)NbO{sub 3}-based lead-free piezoceramic as a model system to investigate the evolution of the extrinsic contribution around a PPB. X-ray diffraction measurements are performed over a wide range of temperatures in order to determine the structures and transitions. The relevance of the extrinsic contribution at the PPB region is evaluated by means of nonlinear dielectric response measurements. Though it is widely appreciated that certain intrinsic properties of ferroelectric materials increase as PPBs are approached, our results demonstrate that the extrinsic contribution also maximizes. An enhancement of the extrinsic contribution is therefore also responsible for improving the functional properties at the PPB region. Rayleigh's law is used to quantitatively analyze the nonlinear response. As a result, an evolution of the domain wall motion dynamics through the PPB region is detected. This work demonstrates that the extrinsic contribution at a PPB may have a dynamic role in lead-free piezoelectric materials, thereby exerting a far greater influence on their functional properties than that considered to date.

Extrinsic photoresponse enhancement under additional intrinsic photoexcitation in organic semiconductors

Energy Technology Data Exchange (ETDEWEB)

Kounavis, P., E-mail: pkounavis@upatras.gr [Department of Electrical and Computer Engineering, School of Engineering, University of Patras, 26504 Patras (Greece)

2016-06-28

Dual light beam photoresponse experiments are employed to explore the photoresponse under simultaneous extrinsic and intrinsic photoexcitation of organic semiconductors. The photoresponse of a red modulated light extrinsic photoexcitation is found that can be significantly enhanced under an additional blue bias-light intrinsic photoexcitation in two terminal pentacene films on glass substrates. From the frequency resolved photoresponse, it is deduced that the phenomenon of photoresponse enhancement can be attributed to an increase in the extrinsic photogeneration rate of the red modulated light and/or an improvement of the drift velocity of carriers under an additional blue light intrinsic photoexcitation. The possible predominant extrinsic photogeneration mechanism, which can be compatible with the observed dependence of the photoresponse enhancement on the frequency and on the light intensities of the red and blue light excitation, is the singlet exciton dissociation through electron transfer to acceptor-like traps. Moreover, an improvement in the drift velocity of carriers traversing grain boundaries with potential energy barriers, which may be reduced by trapping of minority carriers created from the intrinsic photoexcitation, may partly contribute to the photoresponse enhancement.

Extrinsic photoresponse enhancement under additional intrinsic photoexcitation in organic semiconductors

International Nuclear Information System (INIS)

Kounavis, P.

2016-01-01

Dual light beam photoresponse experiments are employed to explore the photoresponse under simultaneous extrinsic and intrinsic photoexcitation of organic semiconductors. The photoresponse of a red modulated light extrinsic photoexcitation is found that can be significantly enhanced under an additional blue bias-light intrinsic photoexcitation in two terminal pentacene films on glass substrates. From the frequency resolved photoresponse, it is deduced that the phenomenon of photoresponse enhancement can be attributed to an increase in the extrinsic photogeneration rate of the red modulated light and/or an improvement of the drift velocity of carriers under an additional blue light intrinsic photoexcitation. The possible predominant extrinsic photogeneration mechanism, which can be compatible with the observed dependence of the photoresponse enhancement on the frequency and on the light intensities of the red and blue light excitation, is the singlet exciton dissociation through electron transfer to acceptor-like traps. Moreover, an improvement in the drift velocity of carriers traversing grain boundaries with potential energy barriers, which may be reduced by trapping of minority carriers created from the intrinsic photoexcitation, may partly contribute to the photoresponse enhancement.

Morphological Study on Room-Temperature-Cured PMMA-Grafted Natural Rubber-Toughened Epoxy/Layered Silicate Nanocomposite

Directory of Open Access Journals (Sweden)

N. Y. Yuhana

2012-01-01

Full Text Available A morphological study was conducted on ternary systems containing epoxy, PMMA-grafted natural rubber, and organic chemically modified montmorillonite (Cloisite 30B. Optical microscopy, transmission electron microscopy (TEM, scanning electron microscopy (SEM, energy dispersive X-ray (EDX, and wide-angle X-ray diffraction (WAXD analysis were used. The following four materials were prepared at room temperature: cured unmodified epoxy, cured toughened epoxy, cured unmodified epoxy/Cloisite 30B nanocomposites, and cured toughened epoxy/Cloisite 30B nanocomposites. Mixing process was performed by mechanical stirring. Poly(etheramine was used as the curing agent. The detailed TEM images revealed co-continuous and dispersed spherical rubber in the epoxy-rubber blend, suggesting a new proposed mechanism of phase separation. High-magnification TEM analysis showed good interactions between rubber and Cloisite 30B in the ternary system. Also, it was found that rubber particles could enhance the separation of silicates layers. Both XRD and TEM analyses confirmed that the intercalation of Cloisite 30B was achieved. No distinct exfoliated silicates were observed by TEM. Aggregates of layered silicates (tactoids were observed by SEM and EDX, in addition to TEM at low magnification. EDX analysis confirmed the presence of organic and inorganic elements in the binary and ternary epoxy systems containing Cloisite 30B.

The effects of extrinsic rewards on children's intrinsic motivation

OpenAIRE

大槻, 千秋

1981-01-01

An experiment was conducted with preschool children to test whether a person's intrinsic motivation in an activity may be decreased by extrinsic salient rewards in Japan like in America. Children solved some jigsaw puzzles and received assorted candies, then they were observed how long they did other jigsaw puzzles. The results showed that the effects of extrinsic rewards on intrinsic motivation in an activity varied with the subject's social background. In uptown children's intrinsic motivat...

Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

OpenAIRE

Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

2017-01-01

Background: According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. () proposed a dichotomy of broad subtypes of extrinsic ...

[EXTRINSIC AND INTRINSIC FACTORS FOR FALLS THAT CAUSED HIP FRACTURE].

Science.gov (United States)

Tsur, Atzmon; Shakeer, Nael; Segal, Zvi; Itah, Dorit; Eluz, Dana

2017-05-01

Among the reasons described as possibly causing falls in older and elderly people are extrinsic factors such as bumping into objects, slipping on a wet floor, etc., and intrinsic factors - those that occur suddenly without warning. To investigate the connection between the reasons for falls, extrinsic or intrinsic and different medical and nonmedical factors. The survey included 82 people, 53 women and 29 men, who fell and broke their hip, underwent surgery, and were treated at the Rehabilitation Department. Data showed that 39 people fell due to extrinsic factors and 43 due to intrinsic reasons. We examined the correlation with several factors, both medical and non-medical, that may have influenced the scenario of each group. Falls due to extrinsic reasons took place at all hours of the day and night, mainly in people who were alone and who wore shoes or sandals at the time of the fall and who either suffered from slight or no disturbances in attention and concentration. Falls due to intrinsic reasons occurred mainly during rest or sleep hours, in people who walked barefoot or with socks or slippers and who suffered moderate or severe disturbances in attention and concentration. Although the differences in the extrinsic vs. intrinsic reasons for falls that led to broken hips were fairly clear, it would be difficult to recommend new tools for prevention of this phenomenon. Trying to predict an infrequent future event such as a traumatic fall is inherently difficult.

Elastomer toughened polyimide adhesives. [bonding metal and composite material structures for aircraft and spacecraft

Science.gov (United States)

St.clair, A. K.; St.clair, T. L. (Inventor)

1985-01-01

A rubber-toughened, addition-type polyimide composition is disclosed which has excellent high temperature bonding characteristics in the fully cured state and improved peel strength and adhesive fracture resistance physical property characteristics. The process for making the improved adhesive involves preparing the rubber-containing amic acid prepolymer by chemically reacting an amine-terminated elastomer and an aromatic diamine with an aromatic dianhydride with which a reactive chain stopper anhydride has been mixed, and utilizing solvent or mixture of solvents for the reaction.

Intrinsic to extrinsic phonon lifetime transition in a GaAs–AlAs superlattice

International Nuclear Information System (INIS)

Hofmann, F; Garg, J; Chen, G; Maznev, A A; Nelson, K A; Jandl, A; Bulsara, M; Fitzgerald, E A

2013-01-01

We have measured the lifetimes of two zone-center longitudinal acoustic phonon modes, at 320 and 640 GHz, in a 14 nm GaAs/2 nm AlAs superlattice structure. By comparing measurements at 296 and 79 K we separate the intrinsic contribution to phonon lifetime determined by phonon–phonon scattering from the extrinsic contribution due to defects and interface roughness. At 296 K, the 320 GHz phonon lifetime has approximately equal contributions from intrinsic and extrinsic scattering, whilst at 640 GHz it is dominated by extrinsic effects. These measurements are compared with intrinsic and extrinsic scattering rates in the superlattice obtained from first-principles lattice dynamics calculations. The calculated room-temperature intrinsic lifetime of longitudinal phonons at 320 GHz is in agreement with the experimentally measured value of 0.9 ns. The model correctly predicts the transition from predominantly intrinsic to predominantly extrinsic scattering; however the predicted transition occurs at higher frequencies. Our analysis indicates that the ‘interfacial atomic disorder’ model is not entirely adequate and that the observed frequency dependence of the extrinsic scattering rate is likely to be determined by a finite correlation length of interface roughness. (paper)

Intrinsic to extrinsic phonon lifetime transition in a GaAs-AlAs superlattice.

Science.gov (United States)

Hofmann, F; Garg, J; Maznev, A A; Jandl, A; Bulsara, M; Fitzgerald, E A; Chen, G; Nelson, K A

2013-07-24

We have measured the lifetimes of two zone-center longitudinal acoustic phonon modes, at 320 and 640 GHz, in a 14 nm GaAs/2 nm AlAs superlattice structure. By comparing measurements at 296 and 79 K we separate the intrinsic contribution to phonon lifetime determined by phonon-phonon scattering from the extrinsic contribution due to defects and interface roughness. At 296 K, the 320 GHz phonon lifetime has approximately equal contributions from intrinsic and extrinsic scattering, whilst at 640 GHz it is dominated by extrinsic effects. These measurements are compared with intrinsic and extrinsic scattering rates in the superlattice obtained from first-principles lattice dynamics calculations. The calculated room-temperature intrinsic lifetime of longitudinal phonons at 320 GHz is in agreement with the experimentally measured value of 0.9 ns. The model correctly predicts the transition from predominantly intrinsic to predominantly extrinsic scattering; however the predicted transition occurs at higher frequencies. Our analysis indicates that the 'interfacial atomic disorder' model is not entirely adequate and that the observed frequency dependence of the extrinsic scattering rate is likely to be determined by a finite correlation length of interface roughness.

Análisis de la estructura organizacional del centro médico popular Dra. Lili Perez Sánchez y propuesta de reestructuración de procesos administrativos para potenciar el servicio al cliente.

OpenAIRE

Carrera Franco, Astrid Carolina; Pazmiño Flores, Tatiana Carolina

2015-01-01

El presente proyecto de investigación se orienta en el análisis de procesos administrativos en el Centro Médico Popular Dra.Lili Pérez Sánchez y reestructuración de estos mediante un estudio de tiempos y movimientos, modificación del manual de procesos para el personal, complementado con estrategias de marketing para llegar acertadamente al cliente. The following investigation project is oriented from the analysis of the administrative processes in the Popular Medical Center Dra.Lili Pérez...

Fitness, Extrinsic Complexity and Informing Science

Directory of Open Access Journals (Sweden)

Grandon Gill

2017-03-01

We raise concerns about society’s continuing investment in academic research that discounts the extrinsic complexity of the domains under study. Future Research We highlight a need for research to operationalize the concepts of fitness and complexity in practice.

Intrinsic and extrinsic motivation among adolescent ten-pin bowlers in kuala lumpur, malaysia.

Science.gov (United States)

Teo, Eng-Wah; Khoo, Selina; Wong, Rebecca; Wee, Eng-Hoe; Lim, Boon-Hooi; Rengasamy, Shabesan Sit

2015-03-29

Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation) was administered. Results showed significant differences (t=10.43, df=239, p=0.01) between total scores of intrinsic and extrinsic motivation among ten-pin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25) or extrinsic (t=-0.51, df=238, p=0.61) motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability.

Science.gov (United States)

Frielink, N; Schuengel, C; Embregts, P

2017-07-01

According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. () proposed a dichotomy of broad subtypes of extrinsic motivation for people with intellectual disability (ID) due to their cognitive limitations. The current study challenges this proposal by testing whether the four subtypes of extrinsic motivation can be differentiated among people with ID as well. The subtypes of extrinsic motivation were measured using two adapted versions of the Self-Regulation Questionnaire, one regarding exercise and one regarding support. In total, 186 adults with mild to borderline ID participated in the study. Results supported the distinction between the four subtypes of extrinsic motivation regarding both exercise and support. In addition, the correlation coefficients supported a quasi-simplex pattern of correlations among the subtypes, indicating that adjacent subtypes were more closely related than non-adjacent subtypes. Moreover, the study showed sufficient Cronbach's alphas and test-retest reliabilities for early stage research. Overall, the results of the current study provide initial evidence for the universality of the four subtypes of extrinsic motivation across populations with and without ID. © 2017 The Authors. Journal of Intellectual Disability Research published by MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disibilities and John Wiley & Sons Ltd.

Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

Directory of Open Access Journals (Sweden)

Teo Eng-Wah

2015-03-01

Full Text Available Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual. A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation was administered. Results showed significant differences (t=10.43, df=239, p=0.01 between total scores of intrinsic and extrinsic motivation among tenpin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=-1.15, df=238, p=0.25 or extrinsic (t=-0.51, df=238, p=0.61 motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers.

Intrinsic and Extrinsic Motivation Among Adolescent Ten-Pin Bowlers in Kuala Lumpur, Malaysia

Science.gov (United States)

Teo, Eng-Wah; Khoo, Selina; Wong, Rebecca; Wee, Eng-Hoe; Lim, Boon-Hooi; Rengasamy, Shabesan Sit

2015-01-01

Motivation has long been associated with sports engagement. However, to date no research has been performed to understand the domain of motivation among ten-pin bowlers. The purpose of this study was to investigate different types of motivation (i.e., intrinsic vs. extrinsic) based on self-determination theory from the perspective of gender and the bowler type (competitive vs. casual). A total of 240 bowlers (104 male, 136 female; 152 competitive, 88 casual) with a mean age of 16.61 ± 0.78 years were recruited in Kuala Lumpur. The Sport Motivation Scale, a 28-item self-report questionnaire measuring seven subscales (i.e., intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, extrinsic motivation to identify regulation, extrinsic motivation for introjection regulation, extrinsic motivation to external regulation, and amotivation) was administered. Results showed significant differences (t=10.43, df=239, p=0.01) between total scores of intrinsic and extrinsic motivation among ten-pin bowlers. There were significant gender differences with respect to intrinsic motivation to know, intrinsic motivation to accomplish, intrinsic motivation to experience stimulation, and extrinsic motivation to identify regulation. However, no significant bowler type differences were found for either the intrinsic (t=−1.15, df=238, p=0.25) or extrinsic (t=−0.51, df=238, p=0.61) motivation dimensions. In conclusion, our study demonstrated substantial intrinsic motivation for gender effects, but no bowler type effects among adolescent ten-pin bowlers. PMID:25964827

Calcium silicate ceramic scaffolds toughened with hydroxyapatite whiskers for bone tissue engineering

International Nuclear Information System (INIS)

Feng, Pei; Wei, Pingpin; Li, Pengjian; Gao, Chengde; Shuai, Cijun; Peng, Shuping

2014-01-01

Calcium silicate possessed excellent biocompatibility, bioactivity and degradability, while the high brittleness limited its application in load-bearing sites. Hydroxyapatite whiskers ranging from 0 to 30 wt.% were incorporated into the calcium silicate matrix to improve the strength and fracture resistance. Porous scaffolds were fabricated by selective laser sintering. The effects of hydroxyapatite whiskers on the mechanical properties and toughening mechanisms were investigated. The results showed that the scaffolds had a uniform and continuous inner network with the pore size ranging between 0.5 mm and 0.8 mm. The mechanical properties were enhanced with increasing hydroxyapatite whiskers, reached a maximum at 20 wt.% (compressive strength: 27.28 MPa, compressive Young's modulus: 156.2 MPa, flexural strength: 15.64 MPa and fracture toughness: 1.43 MPa·m 1/2 ) and then decreased by addition of more hydroxyapatite whiskers. The improvement of mechanical properties was due to whisker pull-out, crack deflection and crack bridging. Moreover, the degradation rate decreased with the increase of hydroxyapatite whisker content. A layer of bone-like apatite was formed on the scaffold surfaces after being soaked in simulated body fluid. Human osteoblast-like MG-63 cells spread well on the scaffolds and proliferated with increasing culture time. These findings suggested that the calcium silicate scaffolds reinforced with hydroxyapatite whiskers showed great potential for bone regeneration and tissue engineering applications. - Highlights: • HA whiskers were incorporated into CS to improve the properties. • The scaffolds were successfully fabricated by SLS. • Toughening mechanisms was whisker pull-out, crack deflection and bridging. • The scaffolds showed excellent apatite forming ability

Calcium silicate ceramic scaffolds toughened with hydroxyapatite whiskers for bone tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Feng, Pei [State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, PR China, (China); Wei, Pingpin [Cancer Research Institute, Central South University, Changsha 410078 (China); Li, Pengjian; Gao, Chengde [State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, PR China, (China); Shuai, Cijun, E-mail: shuai@csu.edu.cn [State Key Laboratory of High Performance Complex Manufacturing, Central South University, Changsha 410083, PR China, (China); Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC 29425 (United States); Peng, Shuping, E-mail: shuping@csu.edu.cn [Cancer Research Institute, Central South University, Changsha 410078 (China)

2014-11-15

Calcium silicate possessed excellent biocompatibility, bioactivity and degradability, while the high brittleness limited its application in load-bearing sites. Hydroxyapatite whiskers ranging from 0 to 30 wt.% were incorporated into the calcium silicate matrix to improve the strength and fracture resistance. Porous scaffolds were fabricated by selective laser sintering. The effects of hydroxyapatite whiskers on the mechanical properties and toughening mechanisms were investigated. The results showed that the scaffolds had a uniform and continuous inner network with the pore size ranging between 0.5 mm and 0.8 mm. The mechanical properties were enhanced with increasing hydroxyapatite whiskers, reached a maximum at 20 wt.% (compressive strength: 27.28 MPa, compressive Young's modulus: 156.2 MPa, flexural strength: 15.64 MPa and fracture toughness: 1.43 MPa·m{sup 1/2}) and then decreased by addition of more hydroxyapatite whiskers. The improvement of mechanical properties was due to whisker pull-out, crack deflection and crack bridging. Moreover, the degradation rate decreased with the increase of hydroxyapatite whisker content. A layer of bone-like apatite was formed on the scaffold surfaces after being soaked in simulated body fluid. Human osteoblast-like MG-63 cells spread well on the scaffolds and proliferated with increasing culture time. These findings suggested that the calcium silicate scaffolds reinforced with hydroxyapatite whiskers showed great potential for bone regeneration and tissue engineering applications. - Highlights: • HA whiskers were incorporated into CS to improve the properties. • The scaffolds were successfully fabricated by SLS. • Toughening mechanisms was whisker pull-out, crack deflection and bridging. • The scaffolds showed excellent apatite forming ability.

Copper-65-absorption by men fed intrinsically and extrinsically labeled whole wheat bread

International Nuclear Information System (INIS)

Johnson, P.E.; Lykken, G.I.

1988-01-01

Six men were fed a diet composed of conventional foods with all bread as whole wheat bread. Intrinsically labeled 65 Cu bread (containing 6.5 ppm Cu and 48 atom % 65 Cu) was substituted for unlabeled bread for 3 days, and stools were collected for 24 days. Extrinsically labeled bread was then substituted for 3 days and another 24-day stool collection made. 65 Cu excretion was measured by mass spectrometry. Mean Cu intake was 1.10 mg of Cu/day. Average Cu balance was /minus/0.06 /+-/ 0.08 mg/day. Average absorption of the intrinsic copper was 72.2 /+-/ 9.3% and of extrinsic Cu 64.2 /+-/ 5.8%. The ratio of extrinsic to intrinsic absorption was 0.906 /+-/ 0.164. Absorption of intrinsic and extrinsic tracers did not differ significantly (p > 0.05) by a paired t-test, and the ratio (E/I) was not significantly different from 1. Use of extrinsic Cu tracers to assess Cu absorption is supported by these results

Engagement in Classroom Learning: Creating Temporal Participation Incentives for Extrinsically Motivated Students through Bonus Credits

Science.gov (United States)

Rassuli, Ali

2012-01-01

Extrinsic inducements to adjust students' learning motivations have evolved within 2 opposing paradigms. Cognitive evaluation theories claim that controlling factors embedded in extrinsic rewards dissipate intrinsic aspirations. Behavioral theorists contend that if engagement is voluntary, extrinsic reinforcements enhance learning without ill…

Fracture toughness measurements on zirconia toughened ceramics

International Nuclear Information System (INIS)

El Sayed Ali, M.; Toft Soerensen, O.

1986-12-01

Three techniques for fracture toughness measurements on zirconia toughened ceramics were evaluated: the notched beam (NB) technique, the indentation fracture (IF) technique and the indentation strength in bending (ISB) technique. Using these techniques comparative measurements were performed on samples prepared by pressing (uniaxial) and sintering of four commercially available powder types. These were: Toya Soda (Japan) powders with the designations TZ3Y (2.86 mole% Y 2 O 3 ), TZ3YA (2.77 mole% Y 2 O 3 , 0.1 wt% Al 2 O 3 ) and TZ3Y20A (2.88 mole% Y 2 O 3 , 20 wt.% Al 2 O 3 ) and a powder supplied by Viking Chemicals (Denmark) designated as YP5Z-2.5 (2.5 mole% Y 2 O 3 ). The measurements showed that similar K Ic values were obtained with the IF- and ISB-techniques, which therefore are recommended for K Ic measurements. Too high values were, however, obtained with the NB-technique which therefore cannot be recommended. Finally, the measurements showed that a high temperature annealing is recommended prior to testing for the IF-technique. (author)

The detrimental effects of extrinsic reinforcement on “Intrinsic motivation”

OpenAIRE

Dickinson, Alyce M.

1989-01-01

Extrinsic consequences have been criticized on the grounds that they decrease intrinsic motivation or internally initiated behavior. Two popular rationales for this criticism, Lepper's overjustification hypothesis (1981) and Deci's motivational theory (Deci & Ryan, 1985), are reviewed and the criticism is then redefined behaviorally. “Intrinsically controlled” behavior is defined as behavior maintained by response-produced reinforcers, and the question concerning extrinsic consequences is thu...

Bimanual motor coordination controlled by cooperative interactions in intrinsic and extrinsic coordinates.

Science.gov (United States)

Sakurada, Takeshi; Ito, Koji; Gomi, Hiroaki

2016-01-01

Although strong motor coordination in intrinsic muscle coordinates has frequently been reported for bimanual movements, coordination in extrinsic visual coordinates is also crucial in various bimanual tasks. To explore the bimanual coordination mechanisms in terms of the frame of reference, here we characterized implicit bilateral interactions in visuomotor tasks. Visual perturbations (finger-cursor gain change) were applied while participants performed a rhythmic tracking task with both index fingers under an in-phase or anti-phase relationship in extrinsic coordinates. When they corrected the right finger's amplitude, the left finger's amplitude unintentionally also changed [motor interference (MI)], despite the instruction to keep its amplitude constant. Notably, we observed two specificities: one was large MI and low relative-phase variability (PV) under the intrinsic in-phase condition, and the other was large MI and high PV under the extrinsic in-phase condition. Additionally, using a multiple-interaction model, we successfully decomposed MI into intrinsic components caused by motor correction and extrinsic components caused by visual-cursor mismatch of the right finger's movements. This analysis revealed that the central nervous system facilitates MI by combining intrinsic and extrinsic components in the condition with in-phases in both intrinsic and extrinsic coordinates, and that under-additivity of the effects is explained by the brain's preference for the intrinsic interaction over extrinsic interaction. In contrast, the PV was significantly correlated with the intrinsic component, suggesting that the intrinsic interaction dominantly contributed to bimanual movement stabilization. The inconsistent features of MI and PV suggest that the central nervous system regulates multiple levels of bilateral interactions for various bimanual tasks. © 2015 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and

Extrinsic spin Nernst effect from first principles.

Science.gov (United States)

Tauber, Katarina; Gradhand, Martin; Fedorov, Dmitry V; Mertig, Ingrid

2012-07-13

We present an ab initio description of the thermal transport phenomenon called the spin Nernst effect. It refers to generation of a spin accumulation or a pure spin current transverse to an applied temperature gradient. This is similar to the intensively studied spin Hall effect described by intrinsic and extrinsic mechanisms due to an applied electric field. Analogously, several contributions are present for the spin Nernst effect. Here we investigate the extrinsic skew scattering mechanism which is dominant in the limit of dilute alloys. Our calculations are based on a fully relativistic Korringa-Kohn-Rostoker method and a solution of the linearized Boltzmann equation. As a first application, we consider a Cu host with Au, Ti, and Bi impurities.

THE EFFECT OF EXTRINSIC MOTIVATION ON ADVERSITY QUOTIENT IN PATIENTS WITH HIV/AIDS

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Nursalam Nursalam

2017-07-01

Full Text Available Introduction: Patients with HIV/AIDS may have various types of psychological responses. It was very difficult situation for them. Difficulty can measured by using Adversity Quotient. As a nurse, we can give extrinsic motivation to bring back the patient HIV/AIDS’s quality of life. The objective of this study was to identify the presence effect of extrinsic motivation on Adversity Quotient in patients with HIV/AIDS in Infectious Disease Intermediateatery Treatment Unit, Dr. Soetomo Hospital, Surabaya. Method: This study was used a quasy experimental purposive sampling design. The population was taken from ambulatory patients. There were 16 respondents who met to the inclusion criteria. The independent variable was extrinsic motivation and dependent variable was Adversity Quotient. Data were collected by using questionnaire and interview, then analyzed by using Wilcoxon Signed Rank Test and Mann Whitney U Test with significance level p=0.05. Result: The result revealed that there was an effect of extrinsic motivation on Adversity Quotient of patients with HIV/AIDS (p=0.017. The extrinsic motivation was found to have an effect on control response (p=0.027 and origin response (p=0.028, there was no influence of extrinsic motivation on ownership response (p=0.334, reach (p=0.129 and endurance (p=0.161. Discussion: It can be concluded that the extrinsic motivation with intervention of social support has a positive effect on the improvement of Adversity Quotient in patients with HIV/AIDS. Further studies should measure the effectiveness of Adversity Quotient training on acceptance response in patients with HIV/AIDS.

Motor memory is encoded as a gain-field combination of intrinsic and extrinsic action representations.

Science.gov (United States)

Brayanov, Jordan B; Press, Daniel Z; Smith, Maurice A

2012-10-24

Actions can be planned in either an intrinsic (body-based) reference frame or an extrinsic (world-based) frame, and understanding how the internal representations associated with these frames contribute to the learning of motor actions is a key issue in motor control. We studied the internal representation of this learning in human subjects by analyzing generalization patterns across an array of different movement directions and workspaces after training a visuomotor rotation in a single movement direction in one workspace. This provided a dense sampling of the generalization function across intrinsic and extrinsic reference frames, which allowed us to dissociate intrinsic and extrinsic representations and determine the manner in which they contributed to the motor memory for a trained action. A first experiment showed that the generalization pattern reflected a memory that was intermediate between intrinsic and extrinsic representations. A second experiment showed that this intermediate representation could not arise from separate intrinsic and extrinsic learning. Instead, we find that the representation of learning is based on a gain-field combination of local representations in intrinsic and extrinsic coordinates. This gain-field representation generalizes between actions by effectively computing similarity based on the (Mahalanobis) distance across intrinsic and extrinsic coordinates and is in line with neural recordings showing mixed intrinsic-extrinsic representations in motor and parietal cortices.

Study on Strengthening and Toughening Mechanisms of Aluminum Alloy 2618-Ti at Elevated Temperature

Science.gov (United States)

Kun, Ma; Tingting, Liu; Ya, Liu; Xuping, Su; Jianhua, Wang

2018-01-01

The tensile properties of the alloy 2618 and 2618-Ti were tested using a tensile testing machine. The morphologies of the fracture of tensile samples were observed using scanning electron microscopy. The strengthening and toughening mechanisms of alloy 2618-Ti at elevated temperature were systematically investigated based on the analyses of experimental results. The results showed that the tensile strength of alloy 2618-Ti is much higher than that of alloy 2618 at the temperature range of 250 and 300 °C. But the elongation of alloy 2618-Ti is much higher than that of alloy 2618 at the temperature range of 200 and 300 °C. The equal-strength temperature of intragranular and grain boundary of alloy 2618-Ti is about 235 °C. When the temperature is lower than 235 °C, the strengthening of alloy 2618-Ti is ascribed to the strengthening effect of fine grains and dispersed Al3Ti/Al18Mg3Ti2 phase. When the temperature is higher than 235 °C, the strengthening effect of alloy 2618-Ti is mainly attributed to the load transfer of Al3Ti and Al18Mg3Ti2 particles. The toughening of alloy 2618-Ti at elevated temperature is mainly ascribed to the fine grain microstructure, excellent combination between matrix and dispersed Al3Ti/Al18Mg3Ti2 particles as well as the recrystallization of the alloy at elevated temperature.

Self-expandable metal stents for malignant esophageal obstruction: a comparative study between extrinsic and intrinsic compression.

Science.gov (United States)

Rhee, K; Kim, J-H; Jung, D H; Han, J W; Lee, Y C; Lee, S K; Shin, S K; Park, J C; Chung, H S; Park, J J; Youn, Y H; Park, H

2016-04-01

Self-expandable metal stents (SEMSs) are effective for malignant esophageal obstruction, but usefulness of SEMSs in extrinsic lesions is yet to be elucidated. This study is aimed at evaluating the clinical usefulness of SEMSs in the extrinsic compression compared with intrinsic. A retrospective review was conducted for 105 patients (intrinsic, 85; extrinsic, 20) with malignant esophageal obstruction who underwent endoscopic SEMSs placement. Technical and clinical success rates were evaluated and clinical outcomes were compared between extrinsic and intrinsic group. Extrinsic group was mostly pulmonary origin. Overall technical and clinical success rate was 100% and 91%, respectively, without immediate complications. Extrinsic and intrinsic group did not differ significantly in clinical success rate. The median stent patency time was 131.3 ± 85.8 days in intrinsic group while that of extrinsic was 54.6 ± 45.1 due to shorter survival after stent insertion. The 4-, 8-, and 12-week patency rates were 90.5%, 78.8%, and 64.9% respectively in intrinsic group, while stents of extrinsic group remained patent until death. Uncovered, fully covered, and double-layered stent were used evenly and the types did not influence patency in both groups. In conclusion, esophageal SEMSs can safely and effectively be used for malignant extrinsic compression as well as intrinsic. © 2015 International Society for Diseases of the Esophagus.

CONSUMER EVALUATIONS OF BEAUTIFICATION PRODUCTS: EFFECTS OF EXTRINSIC CUES

Directory of Open Access Journals (Sweden)

Md. Humayun Kabir Chowdhury

2006-01-01

Full Text Available This study investigates the influence of extrinsic cues, i.e. brand image, perceived price, perceived quality, and perceived country of origin on consumers' evaluative judgments for beautification products. Multi-item measures were used for data collection. Resultsrevealed that three extrinsic cues: brand image, perceived quality, and perceived country of origin have positive and significant influence on consumers' brand evaluation of beautification brands. Only perceived price has shown no such influence on consumers' brand evaluation. Finally, unanswered questions and future researchdirections are presented.

Deterministic analysis of extrinsic and intrinsic noise in an epidemiological model.

Science.gov (United States)

Bayati, Basil S

2016-05-01

We couple a stochastic collocation method with an analytical expansion of the canonical epidemiological master equation to analyze the effects of both extrinsic and intrinsic noise. It is shown that depending on the distribution of the extrinsic noise, the master equation yields quantitatively different results compared to using the expectation of the distribution for the stochastic parameter. This difference is incident to the nonlinear terms in the master equation, and we show that the deviation away from the expectation of the extrinsic noise scales nonlinearly with the variance of the distribution. The method presented here converges linearly with respect to the number of particles in the system and exponentially with respect to the order of the polynomials used in the stochastic collocation calculation. This makes the method presented here more accurate than standard Monte Carlo methods, which suffer from slow, nonmonotonic convergence. In epidemiological terms, the results show that extrinsic fluctuations should be taken into account since they effect the speed of disease breakouts and that the gamma distribution should be used to model the basic reproductive number.

Altered intrinsic and extrinsic connectivity in schizophrenia.

Science.gov (United States)

Zhou, Yuan; Zeidman, Peter; Wu, Shihao; Razi, Adeel; Chen, Cheng; Yang, Liuqing; Zou, Jilin; Wang, Gaohua; Wang, Huiling; Friston, Karl J

2018-01-01

Schizophrenia is a disorder characterized by functional dysconnectivity among distributed brain regions. However, it is unclear how causal influences among large-scale brain networks are disrupted in schizophrenia. In this study, we used dynamic causal modeling (DCM) to assess the hypothesis that there is aberrant directed (effective) connectivity within and between three key large-scale brain networks (the dorsal attention network, the salience network and the default mode network) in schizophrenia during a working memory task. Functional MRI data during an n-back task from 40 patients with schizophrenia and 62 healthy controls were analyzed. Using hierarchical modeling of between-subject effects in DCM with Parametric Empirical Bayes, we found that intrinsic (within-region) and extrinsic (between-region) effective connectivity involving prefrontal regions were abnormal in schizophrenia. Specifically, in patients (i) inhibitory self-connections in prefrontal regions of the dorsal attention network were decreased across task conditions; (ii) extrinsic connectivity between regions of the default mode network was increased; specifically, from posterior cingulate cortex to the medial prefrontal cortex; (iii) between-network extrinsic connections involving the prefrontal cortex were altered; (iv) connections within networks and between networks were correlated with the severity of clinical symptoms and impaired cognition beyond working memory. In short, this study revealed the predominance of reduced synaptic efficacy of prefrontal efferents and afferents in the pathophysiology of schizophrenia.

A Compact Frequency Reconfigurable Hybrid DRA for LTE/Wimax Applications

Directory of Open Access Journals (Sweden)

Sajid Aqeel

2017-01-01

Full Text Available A compact hybrid antenna structure with frequency reconfiguration capabilities is presented in this article. The proposed design employs a combination of a rectangular DR element and a coupling slot on the structure’s ground plane (GP. The slot shifts the fundamental DRA mode by introducing a slow wave effect and its resonant behavior helps to achieve an omnidirectional pattern at low frequencies. The slot is loaded with a series of PIN diode switches whose ON/OFF combinations alter the effective slot length. Slot loading with PIN diodes results in frequency reconfiguration of the proposed structure with a large tuning range of 76.2% (between 1.73 and 3.86 GHz. A parametric analysis was performed to investigate the effects of slot length, width, and position on the reflection coefficients of the proposed structure. A prototype of the proposed design was fabricated and results were measured. The measured results show a close agreement with the simulated ones. The proposed design is suitable for DCS 1800 MHz, PCS 1900 MHZ, UMTS, LTE 2500–2700 MHz, and Wimax 3.5 GHz.

Extrinsic and intrinsic curvatures in thermodynamic geometry

Energy Technology Data Exchange (ETDEWEB)

Hosseini Mansoori, Seyed Ali, E-mail: shossein@bu.edu [Department of Physics, Boston University, 590 Commonwealth Ave., Boston, MA 02215 (United States); Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Mirza, Behrouz, E-mail: b.mirza@cc.iut.ac.ir [Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of); Sharifian, Elham, E-mail: e.sharifian@ph.iut.ac.ir [Department of Physics, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

2016-08-10

We investigate the intrinsic and extrinsic curvatures of a certain hypersurface in thermodynamic geometry of a physical system and show that they contain useful thermodynamic information. For an anti-Reissner–Nordström-(A)de Sitter black hole (Phantom), the extrinsic curvature of a constant Q hypersurface has the same sign as the heat capacity around the phase transition points. The intrinsic curvature of the hypersurface can also be divergent at the critical points but has no information about the sign of the heat capacity. Our study explains the consistent relationship holding between the thermodynamic geometry of the KN-AdS black holes and those of the RN (J-zero hypersurface) and Kerr black holes (Q-zero hypersurface) ones [1]. This approach can easily be generalized to an arbitrary thermodynamic system.

Extrinsic and intrinsic curvatures in thermodynamic geometry

International Nuclear Information System (INIS)

Hosseini Mansoori, Seyed Ali; Mirza, Behrouz; Sharifian, Elham

2016-01-01

We investigate the intrinsic and extrinsic curvatures of a certain hypersurface in thermodynamic geometry of a physical system and show that they contain useful thermodynamic information. For an anti-Reissner–Nordström-(A)de Sitter black hole (Phantom), the extrinsic curvature of a constant Q hypersurface has the same sign as the heat capacity around the phase transition points. The intrinsic curvature of the hypersurface can also be divergent at the critical points but has no information about the sign of the heat capacity. Our study explains the consistent relationship holding between the thermodynamic geometry of the KN-AdS black holes and those of the RN (J-zero hypersurface) and Kerr black holes (Q-zero hypersurface) ones [1]. This approach can easily be generalized to an arbitrary thermodynamic system.

Toughening effect of multi-walled boron nitride nanotubes and their influence on the sintering behaviour of 3Y-TZP zirconia ceramics

Czech Academy of Sciences Publication Activity Database

Tatarko, Peter; Grasso, S.; Chlup, Zdeněk; Porwal, H.; Kasiarova, M.; Dlouhý, Ivo; Reece, M.J.

2014-01-01

Roč. 34, č. 7 (2014), s. 1829-1843 ISSN 0955-2219 EU Projects: European Commission(XE) 264526 - GLACERCO Institutional support: RVO:68081723 Keywords : Zirconia * Boron nitride nanotubes * Composite * Spark plasma sintering * Toughening mechanism Subject RIV: JI - Composite Materials Impact factor: 2.947, year: 2014

Static and dynamic strain energy release rates in toughened thermosetting composite laminates

Science.gov (United States)

Cairns, Douglas S.

1992-01-01

In this work, the static and dynamic fracture properties of several thermosetting resin based composite laminates are presented. Two classes of materials are explored. These are homogeneous, thermosetting resins and toughened, multi-phase, thermosetting resin systems. Multi-phase resin materials have shown enhancement over homogenous materials with respect to damage resistance. The development of new dynamic tests are presented for composite laminates based on Width Tapered Double Cantilevered Beam (WTDCB) for Mode 1 fracture and the End Notched Flexure (ENF) specimen. The WTDCB sample was loaded via a low inertia, pneumatic cylinder to produce rapid cross-head displacements. A high rate, piezo-electric load cell and an accelerometer were mounted on the specimen. A digital oscilloscope was used for data acquisition. Typical static and dynamic load versus displacement plots are presented. The ENF specimen was impacted in three point bending with an instrumented impact tower. Fracture initiation and propagation energies under static and dynamic conditions were determined analytically and experimentally. The test results for Mode 1 fracture are relatively insensitive to strain rate effects for the laminates tested in this study. The test results from Mode 2 fracture indicate that the toughened systems provide superior fracture initiation and higher resistance to propagation under dynamic conditions. While the static fracture properties of the homogeneous systems may be relatively high, the apparent Mode 2 dynamic critical strain energy release rate drops significantly. The results indicate that static Mode 2 fracture testing is inadequate for determining the fracture performance of composite structures subjected to conditions such as low velocity impact. A good correlation between the basic Mode 2 dynamic fracture properties and the performance is a combined material/structural Compression After Impact (CAI) test is found. These results underscore the importance of

Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

NARCIS (Netherlands)

Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

NARCIS (Netherlands)

Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

2017-01-01

Background: According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and

Not All Ideals are Equal: Intrinsic and Extrinsic Ideals in Relationships.

Science.gov (United States)

Rodriguez, Lindsey M; Hadden, Benjamin W; Knee, C Raymond

2015-03-01

The ideal standards model suggests that greater consistency between ideal standards and actual perceptions of one's relationship predicts positive relationship evaluations; however, no research has evaluated whether this differs across types of ideals. A self-determination theory perspective was derived to test whether satisfaction of intrinsic ideals buffers the importance of extrinsic ideals. Participants (N=195) in committed relationships directly and indirectly reported the extent to which their partner met their ideal on two dimensions: intrinsic (e.g., warm, intimate) and extrinsic (e.g., attractive, successful). Relationship need fulfillment and relationship quality were also assessed. Hypotheses were largely supported, such that satisfaction of intrinsic ideals more strongly predicted relationship functioning, and satisfaction of intrinsic ideals buffered the relevance of extrinsic ideals for outcomes.

The Effect of Extrinsic Motivational Factors Towards Iba Student Achievement

OpenAIRE

Pangemanan, Sifrid S.; Saerang, David Paul Elia; Rondonuwu, Mariska

2014-01-01

The reason students can facing the world of competition because they have a motivation. A thing that help students to get their motivation when they are not get a motivation by themself is through extrinsic motivational factors. There are two objectives of this research are to analyze the effect of extrinsic motivational factors towards student achievement and to identify the most influental factors on student achievement. The method is multiple linear regression analysis to examine the effec...

Extrinsic Motivation Index: A New Tool for Managing Labor Productivity

Directory of Open Access Journals (Sweden)

Berumen, S.A.

2016-07-01

Full Text Available The objective of this paper is to provide a tool of practical significance for HR managers and firm executives. This tool, which is called Extrinsic Motivation Index (EMI, is meant to measure the extrinsic motivation of employees. By measuring employees' extrinsic motivation, managers are able to track job satisfaction and, subsequently, implement measures aiming both to raise job satisfaction and to improve organizational commitment. In order to test the validity of the model, we apply the EMI to Faculty members at Spanish and German universities. We also carry out simulation experiments in order to to address all possible situations an organization most probably will have to deal with. The results point out significant differences in the level of motivation and commitment of Faculty members. Additionally, the analysis shows several ways in which an organization may manage job satisfaction issues according to on its level of resources.

Carbon black reinforced C8 ether linked bismaleimide toughened electrically conducting epoxy nanocomposites

International Nuclear Information System (INIS)

Mandhakini, M.; Chandramohan, A.; Jayanthi, K.; Alagar, M.

2014-01-01

Highlight: • The toughness of the epoxy is improved with C8e-BMI. • Conduction through ohmic contact chain takes the leading mechanism for electrical conduction instead of tunneling with 5 wt% CB. • The phase segregation between epoxy/C8 e-BMI improves the toughness of the nanocomposite. • Both toughening and flexibilization effect is responsible for improvement in impact strength. • The largest challenge of appropriate balance between the electrical conductivity and mechanical behavior is attained in a cost effective manner. - Abstract: The present work deals with the toughening of brittle epoxy matrix with C8 ether linked bismaleimide (C8 e-BMI) and then study the reinforcing effect of carbon black (CB) in enhancing the conducting properties of insulating epoxy matrix. The Fourier transform infrared spectroscopy (FTIR) and Raman analysis indicate the formation of strong covalent bonds between CB and C8 e-BMI/epoxy matrix. The X-ray diffraction (XRD) and Field Emission Scanning Electron Microscope (FESEM) analysis indicate the event of phase separation in 5 wt% CB loaded epoxy C8 e-BMI nanocomposites. The impact strength increased up to 5 wt% of CB loading with particle pull and crack deflection to be driving mechanism for enhancing the toughness of the nanocomposite and beyond 5 wt% the impact strength started to decrease due to aggregation of CB. The dynamic mechanical analysis (DMA) also indicates the toughness of the nanocomposites was improved with 5 wt% of CB loading due to the phase segregation between epoxy and C8 e-BMI in the presence of CB. The electrical conductivity was also increased with 5 wt% of CB due to classical conduction by ohmic chain contact

Generational differences in American students' reasons for going to college, 1971-2014: The rise of extrinsic motives.

Science.gov (United States)

Twenge, Jean M; Donnelly, Kristin

2016-01-01

We examined generational differences in reasons for attending college among a nationally representative sample of college students (N = 8 million) entering college between 1971-2014. We validated the items on reasons for attending college against an established measure of extrinsic and intrinsic values among college students in 2014 (n = 189). Millennials (in college 2000s-2010s) and Generation X (1980s-1990s) valued extrinsic reasons for going to college ("to make more money") more, and anti-extrinsic reasons ("to gain a general education and appreciation of ideas") less than Boomers when they were the same age in the 1960s-1970s. Extrinsic reasons for going to college were higher in years with more income inequality, college enrollment, and extrinsic values. These results mirror previous research finding generational increases in extrinsic values begun by GenX and continued by Millennials, suggesting that more recent generations are more likely to favor extrinsic values in their decision-making.

Dynamic mechanical properties of toughened polyamide composites

International Nuclear Information System (INIS)

Alsewailem, Fares D.

2008-01-01

The effect of incorporating thermoplastic rubber on the dynamic mechanical properties, storage and loss moduli, of virgin and recycled glass-fiber-reinforced polyamide 66 has been investigated in this study. Styrene-Ethylene-Styrene and Ethylene-Propylene grafted with maleic anhydride were used as elastomers for toughening. Dynamic mechanical properties of the composites were examined by the rotational rhometry. Shear storage and loss moduli of recycled and virgin materials were measured against frequency. Also the variation of storage modulus of the virgin composites was measured against temperatures by conducting a series of torsion tests. Both dynamic storage and loss moduli of the composites were found to increase with increasing glass fiber and rubber contents. Recycled composites had lower values of dynamic modulus compared that of virgin composites; however by proper combining of fiber and rubber into the recycled material, its modulus fairly matches that of the virgin material. Addition of rubber to virgin composites causes a reduction in G' as temperature increases. Rubber, which acts as a stress concentrator, had a major effect on minimizing the overall modulus of the composites. The in G' versus temperature has been observed for all composites: however the temperature at which the transition G' occurs decreases with increasing rubber content. (author)

Predictors of employment in schizophrenia: The importance of intrinsic and extrinsic motivation.

Science.gov (United States)

Reddy, L Felice; Llerena, Katiah; Kern, Robert S

2016-10-01

Unemployment is a primary functional deficit for the majority of adults with schizophrenia. Research indicates that over two-thirds of adults living in the community with schizophrenia are unemployed. Despite effective programs to assist with job identification and placement, the ability to attain and maintain employment remains a pressing concern. A contributing factor that may be relevant but has received little attention in the work rehabilitation literature is motivation. People with schizophrenia show marked deficits in both intrinsic and extrinsic motivation but these deficits have not been directly examined in relation to work outcomes. The present study sought to examine the relationship between intrinsic and extrinsic motivation and work outcome among a sample of 65 adults with schizophrenia enrolled in a supported employment program. One-third of the participants in the study obtained work. Intrinsic motivation related to valuing and feeling useful in a work role significantly predicted who would obtain employment. Extrinsic motivation related to gaining rewards and avoiding obstacles showed a non-significant trend-level relationship such that workers had higher extrinsic motivation than nonworkers. These findings highlight the importance of considering both intrinsic and extrinsic motivation in work-related interventions and supported employment for individuals with schizophrenia. The results are discussed in terms of clinical implications for improving rehabilitation and occupational outcomes in schizophrenia. Published by Elsevier B.V.

Bridging the gap between extrinsic and intrinsic motivation in the cognitive remediation of schizophrenia.

Science.gov (United States)

Silverstein, Steven M

2010-09-01

An important development in cognitive remediation of schizophrenia is a focus on motivation. However, following a distinction between the concepts of intrinsic motivation (IM) and extrinsic motivation, discussions of IM-based methods have downplayed or misrepresented the role that extrinsic rewards can, and actually do, serve to promote positive treatment outcomes in cognitive remediation. Therefore, the purpose of this article is to explore the rationale for using techniques incorporating extrinsic rewards into cognitive treatment of people with schizophrenia. To do this, evidence is presented on each of the following points: (1) there is a long history of research demonstrating that delivery of extrinsic reward is associated with positive outcomes in both behavioral and cognitive rehabilitation; (2) basic human brain systems respond strongly to tangible rewards, and this can directly enhance attention, working memory, and other cognitive functions; (3) nearly all data on the negative effects of extrinsic reward on IM have come from studies of healthy children and adults in school or work settings who have adequate IM for target tasks; these findings do not generalize well to cognitive remediation settings for people with schizophrenia, who often have abnormally low levels of IM and low base rates of attentive behaviors; and (4) in real-world situations, cognitive remediation interventions already utilize a combination of intrinsic and extrinsic reinforcers. Future studies are needed to clarify state and trait factors responsible for individual differences in the extent to which extrinsic rewards are necessary to set the conditions under which IM can develop.

Raising trophy kids: The role of mothers' contingent self-esteem in maternal promotion of extrinsic goals.

Science.gov (United States)

Soenens, Bart; Wuyts, Dorien; Vansteenkiste, Maarten; Mageau, Geneviève A; Brenning, Katrijn

2015-07-01

This study examined the role of mothers' child-invested contingent self-esteem, that is, their tendency to hinge their self-worth on their child's achievements, in maternal promotion of extrinsic goals, as perceived by adolescents. It was also examined whether maternal promotion of extrinsic goals would, in turn, relate to adolescents' Social Dominance Orientation (SDO). Participants were 184 mothers and their adolescent children (66% female). Maternal child-invested contingent self-esteem predicted adolescent-perceived maternal promotion of extrinsic goals, even when taking into account the variance shared between the promotion of extrinsic goals and mothers' use of a controlling parenting style. Maternal child-invested contingent self-esteem also moderated associations between mothers' personal pursuit of extrinsic goals and their promotion of those goals, such that the association between mothers' own extrinsic goals and their promotion of those goals was significant only among mothers high on child-invested contingent self-esteem. Maternal promotion of extrinsic goals was, in turn, related to adolescent SDO, suggesting that the dynamics examined in this study ultimately relate to adolescents' social and ideological development. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Intrinsic and extrinsic motivation and intention to breast-feed.

Science.gov (United States)

Wells, Kristen J; Thompson, Nancy J; Kloeblen-Tarver, Amy S

2002-01-01

To examine the feasibility of using the cognitive evaluation theory to examine pregnant women's intention to breast-feed. A questionnaire designed to measure intrinsic and extrinsic motivation was administered to 228 pregnant women. Results provide evidence for reliability and validity of the revised instrument in this population. A factor analysis suggests the instrument measures 2 types of intrinsic motivation, one type of extrinsic motivation, and motivation related to the baby. The instrument distinguished differences in motivation between women who intend to breast-feed and those who intend to formula feed. This study helps elucidate motivational factors involved in infant-feeding decisions.

Extrinsic wrist ligaments: prevalence of injury by magnetic resonance imaging and association with intrinsic ligament tears.

Science.gov (United States)

Taneja, Atul K; Bredella, Miriam A; Chang, Connie Y; Joseph Simeone, F; Kattapuram, Susan V; Torriani, Martin

2013-01-01

The objective of this study was to determine the prevalence of extrinsic wrist ligament injury by magnetic resonance imaging and its association with intrinsic ligament tears. We reviewed conventional magnetic resonance images performed over a 5-year period from adult patients in the setting of wrist trauma. Two musculoskeletal radiologists examined the integrity of wrist ligaments and presence of bone abnormalities. In a cohort of 75 subjects, extrinsic ligament injury was present in 75%, with radiolunotriquetral being most frequently affected (45%). Intrinsic ligament injury was present in 60%. Almost half of subjects had combined intrinsic and extrinsic ligament injury. Bone abnormalities were seen in 69%. The rate of extrinsic injury was higher in subjects with bone injury (P = 0.008). There is high prevalence of extrinsic ligament injury in the setting of wrist trauma, especially in the presence of bone abnormalities, with combined injury of intrinsic and extrinsic ligaments in about half of cases.

Separation of extrinsic and intrinsic plasmon excitations in Ge KLL Auger spectra

International Nuclear Information System (INIS)

Berenyi, Z.; Aszalos-Kiss, B.; Csik, A.; Toth, J.; Koever, L.; Varga, D.

2002-01-01

The nature of the Ge satellite structure and the contributions from extrinsic and intrinsic processes were investigated using the ESA-31 electron spectrometer. These measurements are providing the first high energy resolution Ge KLL data. The intensity ratio of the plasmon peaks induced by intrinsic and extrinsic excitation processes is found. (R.P.)

Intrinsic and extrinsic geometries of a tidally deformed black hole

International Nuclear Information System (INIS)

Vega, Ian; Poisson, Eric; Massey, Ryan

2011-01-01

A description of the event horizon of a perturbed Schwarzschild black hole is provided in terms of the intrinsic and extrinsic geometries of the null hypersurface. This description relies on a Gauss-Codazzi theory of null hypersurfaces embedded in spacetime, which extends the standard theory of spacelike and timelike hypersurfaces involving the first and second fundamental forms. We show that the intrinsic geometry of the event horizon is invariant under a reparameterization of the null generators, and that the extrinsic geometry depends on the parameterization. Stated differently, we show that while the extrinsic geometry depends on the choice of gauge, the intrinsic geometry is gauge invariant. We apply the formalism to solutions to the vacuum field equations that describe a tidally deformed black hole. In a first instance, we consider a slowly varying, quadrupolar tidal field imposed on the black hole, and in a second instance, we examine the tide raised during a close parabolic encounter between the black hole and a small orbiting body.

Extrinsic CPT violation in neutrino oscillations in matter

International Nuclear Information System (INIS)

Jacobson, Magnus; Ohlsson, Tommy

2004-01-01

We investigate matter-induced (or extrinsic) CPT violation effects in neutrino oscillations in matter. Especially, we present approximate analytical formulas for the CPT-violating probability differences for three flavor neutrino oscillations in matter with an arbitrary matter density profile. Note that we assume that the CPT invariance theorem holds, which means that the CPT violation effects arise entirely because of the presence of matter. As special cases of matter density profiles, we consider constant and step-function matter density profiles, which are relevant for neutrino oscillation physics in accelerator and reactor long baseline experiments as well as neutrino factories. Finally, the implications of extrinsic CPT violation on neutrino oscillations in matter for several past, present, and future long baseline experiments are estimated

Influential Effects of Intrinsic-Extrinsic Incentive Factors on Management Performance in New Energy Enterprises.

Science.gov (United States)

Wang, Ping; Lu, Zhengnan; Sun, Jihong

2018-02-08

Background : New energy has become a key trend for global energy industry development. Talent plays a very critical role in the enhancement of new energy enterprise competitiveness. As a key component of talent, managers have been attracting more and more attention. The increase in job performance relies on, to a certain extent, incentive mechanism. Based on the Two-factor Theory, differences in influences and effects of different incentives on management performance have been checked in this paper from an empirical perspective. Methods : This paper selects the middle and low level managers in new energy enterprises as research samples and classifies the managers' performance into task performance, contextual performance and innovation performance. It uses manager performance questionnaires and intrinsic-extrinsic incentive factor questionnaires to investigate and study the effects and then uses Amos software to analyze the inner link between the intrinsic-extrinsic incentives and job performance. Results : Extrinsic incentives affect task performance and innovation performance positively. Intrinsic incentives impose active significant effects on task performance, contextual performance, and innovation performance. The intrinsic incentive plays a more important role than the extrinsic incentive. Conclusions : Both the intrinsic-extrinsic incentives affect manager performance positively and the intrinsic incentive plays a more important role than the extrinsic incentive. Several suggestions to management should be given based on these results.

Influential Effects of Intrinsic-Extrinsic Incentive Factors on Management Performance in New Energy Enterprises

Directory of Open Access Journals (Sweden)

Ping Wang

2018-02-01

Full Text Available Background: New energy has become a key trend for global energy industry development. Talent plays a very critical role in the enhancement of new energy enterprise competitiveness. As a key component of talent, managers have been attracting more and more attention. The increase in job performance relies on, to a certain extent, incentive mechanism. Based on the Two-factor Theory, differences in influences and effects of different incentives on management performance have been checked in this paper from an empirical perspective. Methods: This paper selects the middle and low level managers in new energy enterprises as research samples and classifies the managers’ performance into task performance, contextual performance and innovation performance. It uses manager performance questionnaires and intrinsic-extrinsic incentive factor questionnaires to investigate and study the effects and then uses Amos software to analyze the inner link between the intrinsic-extrinsic incentives and job performance. Results: Extrinsic incentives affect task performance and innovation performance positively. Intrinsic incentives impose active significant effects on task performance, contextual performance, and innovation performance. The intrinsic incentive plays a more important role than the extrinsic incentive. Conclusions: Both the intrinsic-extrinsic incentives affect manager performance positively and the intrinsic incentive plays a more important role than the extrinsic incentive. Several suggestions to management should be given based on these results.

Intrinsic and Extrinsic Motivational Factors Related to Educators' Pursuit of Doctoral Degrees

Science.gov (United States)

George-Reid, Kimberly A.

2016-01-01

The purpose of this study was to identify intrinsic and extrinsic motivational factors for professional doctoral degree attainment among educators. The researcher examined the following intrinsic motivating factors: personal attainment, skill and ability enhancement, and goals. The researcher also included the following extrinsic factors:…

Graphene nanosheet-induced toughening of yttria-stabilized zirconia

Energy Technology Data Exchange (ETDEWEB)

Su, Jianan; Chen, Yao; Huang, Qiqi [Soochow University, School of Mechanical and Electric Engineering, Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou (China)

2017-01-15

Graphene nanosheet (GNS)-reinforced yttria-stabilized tetragonal zirconia polycrystals (TZP) were synthesized using spark plasma sintering (SPS), and the influences of the added GNSs on microstructure evolution and the microscopic mechanical properties of the sintered composites were investigated. Raman spectroscopy and microstructure observation corroborated that these added GNSs, which can survive the harsh SPS processing condition, homogeneously distribute in the matrix of all composites to hinder significantly the grain growth. In comparison with the monolithic TZP, the indentation fracture toughness of a GNS/TZP composite reaches maximum value and increases by up to ∝36% (from ∝4.1 to ∝5.6 MPa m{sup 0.5}) even at 0.5% weight fraction, GNS pullout, crack bridging, crack deflection, and crack branching are responsible for the increased fracture toughness. The computed energy dissipation by GNS pullout decreases with increasing the number of graphene layers due to weak bonding between them, and therefore, graphene agglomeration would impair toughening effect. Moreover, scratch studies suggest that GNS/TZP composites exhibit improved scratch resistance due to the fact that GNSs are promising reinforcing and lubricating nanofillers in ceramic composites. (orig.)

Extrinsic Calibration of Camera and 2D Laser Sensors without Overlap

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Khalil M. Ahmad Yousef

2017-10-01

Full Text Available Extrinsic calibration of a camera and a 2D laser range finder (lidar sensors is crucial in sensor data fusion applications; for example SLAM algorithms used in mobile robot platforms. The fundamental challenge of extrinsic calibration is when the camera-lidar sensors do not overlap or share the same field of view. In this paper we propose a novel and flexible approach for the extrinsic calibration of a camera-lidar system without overlap, which can be used for robotic platform self-calibration. The approach is based on the robot–world hand–eye calibration (RWHE problem; proven to have efficient and accurate solutions. First, the system was mapped to the RWHE calibration problem modeled as the linear relationship AX = ZB , where X and Z are unknown calibration matrices. Then, we computed the transformation matrix B , which was the main challenge in the above mapping. The computation is based on reasonable assumptions about geometric structure in the calibration environment. The reliability and accuracy of the proposed approach is compared to a state-of-the-art method in extrinsic 2D lidar to camera calibration. Experimental results from real datasets indicate that the proposed approach provides better results with an L2 norm translational and rotational deviations of 314 mm and 0 . 12 ∘ respectively.

Extrinsic Calibration of Camera and 2D Laser Sensors without Overlap.

Science.gov (United States)

Ahmad Yousef, Khalil M; Mohd, Bassam J; Al-Widyan, Khalid; Hayajneh, Thaier

2017-10-14

Extrinsic calibration of a camera and a 2D laser range finder (lidar) sensors is crucial in sensor data fusion applications; for example SLAM algorithms used in mobile robot platforms. The fundamental challenge of extrinsic calibration is when the camera-lidar sensors do not overlap or share the same field of view. In this paper we propose a novel and flexible approach for the extrinsic calibration of a camera-lidar system without overlap, which can be used for robotic platform self-calibration. The approach is based on the robot-world hand-eye calibration (RWHE) problem; proven to have efficient and accurate solutions. First, the system was mapped to the RWHE calibration problem modeled as the linear relationship AX = ZB , where X and Z are unknown calibration matrices. Then, we computed the transformation matrix B , which was the main challenge in the above mapping. The computation is based on reasonable assumptions about geometric structure in the calibration environment. The reliability and accuracy of the proposed approach is compared to a state-of-the-art method in extrinsic 2D lidar to camera calibration. Experimental results from real datasets indicate that the proposed approach provides better results with an L2 norm translational and rotational deviations of 314 mm and 0 . 12 ∘ respectively.

Aging in the Male Face: Intrinsic and Extrinsic Factors.

Science.gov (United States)

Keaney, Terrence C

2016-07-01

Gender is one of the most significant factors that influence facial anatomy and behavior, both key factors in the aging process. To review male facial anatomy, physiology, and behavior and how it contributes to sexual dimorphism in facial aging. A MEDLINE search was performed for publications on gender differences in facial anatomy, aging, cutaneous physiology, and behavior. There are differences in both intrinsic and extrinsic aging factors in men. Men have a thicker epidermis and dermis with more active cutaneous appendages including hair growth. Male skin has a reduced antioxidant capacity and increased ultraviolet-induced immunosuppression. The male face is larger and has a unique square shape with less subcutaneous soft tissue, especially at the medial cheek. Men are also more prone to smoking and exhibiting poor sun-protective behavior. The differences in intrinsic and extrinsic aging factors contribute to poor facial aging in men. Men develop more severe rhytides in a unique pattern, show increased periocular aging changes, and are more prone to hair loss. This review provides insight into the factors contributing to accelerated male facial aging. Understanding gender differences in aging will help physicians tailor cosmetic treatments for men and minimize extrinsic aging factors.

Extrinsic incentives and tax compliance

OpenAIRE

Sour, Laura; Gutiérrez Andrade, Miguel Ángel

2011-01-01

This paper models the impact of extrinsic incentives in a tax compliance model. It also provides experimental evidence that confirms the existence of a positive relationship between rewards and tax compliance. If individuals are audited, rewards for honest taxpayers are effective in increasing the level of tax compliance. These results are particularly relevant in countries where there is little respect for tax law since rewards can contribute to crowding in the intrinsic motivation to comply.

Dominance dynamics of competition between intrinsic and extrinsic grouping cues.

Science.gov (United States)

Luna, Dolores; Villalba-García, Cristina; Montoro, Pedro R; Hinojosa, José A

2016-10-01

In the present study we examined the dominance dynamics of perceptual grouping cues. We used a paradigm in which participants selectively attended to perceptual groups based on several grouping cues in different blocks of trials. In each block, single and competing grouping cues were presented under different exposure durations (50, 150 or 350ms). Using this procedure, intrinsic vs. intrinsic cues (i.e. proximity and shape similarity) were compared in Experiment 1; extrinsic vs. extrinsic cues (i.e. common region and connectedness) in Experiment 2; and intrinsic vs. extrinsic cues (i.e. common region and shape similarity) in Experiment 3. The results showed that in Experiment 1, no dominance of any grouping cue was found: shape similarity and proximity grouping cues showed similar reaction times (RTs) and interference effects. In contrast, in Experiments 2 and 3, common region dominated processing: (i) RTs to common region were shorter than those to connectedness (Exp. 2) or shape similarity (Exp. 3); and (ii) when the grouping cues competed, common region interfered with connectedness (Exp. 2) and shape similarity (Exp. 3) more than vice versa. The results showed that the exposure duration of stimuli only affected the connectedness grouping cue. An important result of our experiments indicates that when two grouping cues compete, both the non-attended intrinsic cue in Experiment 1, and the non-dominant extrinsic cue in Experiments 2 and 3, are still perceived and they are not completely lost. Copyright © 2016 Elsevier B.V. All rights reserved.

A comparison of South African and German extrinsic and intrinsic motivation

OpenAIRE

Snelgar, Robin; Shelton, Stacy A.; Giesser, Anne

2017-01-01

Background: Various researchers have identified a trend of individuals shifting their preference from extrinsic to intrinsic motivation. The authors aimed to research this phenomenon specifically within the context of two different cultures as to date, this had not been done. This research explored the differing levels of extrinsic and intrinsic motivation in Germans and South Africans. Aim: The main objective of this study was to investigate similarities and differences concerning extrins...

Ultralow-Carbon Nanotube-Toughened Epoxy: The Critical Role of a Double-Layer Interface.

Science.gov (United States)

Liu, Jingwei; Chen, Chao; Feng, Yuezhan; Liao, Yonggui; Ye, Yunsheng; Xie, Xiaolin; Mai, Yiu-Wing

2018-01-10

Understanding the chemistry and structure of interfaces within epoxy resins is important for studying the mechanical properties of nanofiller-filled nanocomposites as well as for developing high-performance polymer nanocomposites. Despite the intensive efforts to construct nanofiller/matrix interfaces, few studies have demonstrated an enhanced stress-transferring efficiency while avoiding unfavorable deformation due to undesirable interface fractures. Here, we report an optimized method to prepare epoxy-based nanocomposites whose interfaces are chemically modulated by poly(glycidyl methacrylate)-block-poly(hexyl methacrylate) (PGMA-b-PHMA)-functionalized multiwalled carbon nanotubes (bc@fMWNTs) and also offer a fundamental explanation of crack growth behavior and the toughening mechanism of the resulting nanocomposites. The presence of block copolymers on the surface of the MWNT results in a promising double-layered interface, in which (1) the outer-layered PGMA segment provides good dispersion in and strong interface bonding with the epoxy matrix, which enhances load transfer efficiency and debonding stress, and (2) the interlayered rubbery PHMA segment around the MWNT provides the maximum removable space for nanotubes as well as triggering cavitation while promoting local plastic matrix deformation, for example, shear banding to dissipate fracture energy. An outstanding toughening effect is achieved with only a 0.05 wt % carbon nanotube loading with the bc@fMWNT, that is, needing only a 20-times lower loading to obtain improvements in fracture toughness comparable to epoxy-based nanocomposites. The enhancements of their corresponding ultimate mode-I fracture toughnesses and fracture energies are 4 times higher than those of pristine MWNT-filled epoxy. These results demonstrate that a MWNT/epoxy interface could be optimized by changing the component structure of grafted modifiers, thereby facilitating the transfer of both mechanical load and energy dissipation

Moisture curable toughened poly(lactide utilizing vinyltrimethoxysilane based crosslinks

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J. Schneider

2016-10-01

Full Text Available Vinyltrimethoxysilane (VTMOS was grafted on to the backbone of poly(lactide (PLA through a free radical grafting reaction using reactive extrusion (REX processing. The methoxy groups of the silane provide the modified PLA sites for crosslinking through a moisture induced pathway. VTMOS grafting efficiencies of up to 90% were obtained. The newly created methoxy functionality of the modified PLA readily undergoes hydrolysis and condensation forming siloxane crosslinks in the material. Crosslinking with VTMOS exhibited improved modulus, strength, and impact toughness while showing a decrease in ductility. Incorporating silanol-terminated poly(dimethylsiloxane (OH-PDMS resulted in the formation of longer siloxane crosslinks. These samples showed an increase in modulus and impact toughness due to the crosslinking, while the longer siloxane linkages resulted in improved ductility and tensile toughness. This is unusual for polymers toughened through crosslinking reactions. Scanning Electron Microscopy (SEM of the fractured surfaces showed the presence of these elongated siloxane crosslinks. This enhanced ability for the modified PLA to deform and absorb energy results in the increase in both impact and tensile toughness.

Toughening mechanisms in interfacially modified HDPE/thermoplastic starch blends.

Science.gov (United States)

Taguet, Aurélie; Bureau, Martin N; Huneault, Michel A; Favis, Basil D

2014-12-19

The mechanical behavior of polymer blends containing 80 wt% of HDPE and 20 wt% of TPS and compatibilized with HDPE-g-MA grafted copolymer was investigated. Unmodified HDPE/TPS blends exhibit high fracture resistance, however, the interfacial modification of those blends by addition of HDPE-g-MA leads to a dramatic drop in fracture resistance. The compatibilization of HDPE/TPS blends increases the surface area of TPS particles by decreasing their size. It was postulated that the addition of HDPE-g-MA induces a reaction between maleic anhydride and hydroxyl groups of the glycerol leading to a decrease of the glycerol content in the TPS phase. This phenomenon increases the stiffness of the modified TPS particles and stiffer TPS particles leading to an important reduction in toughness and plastic deformation, as measured by the EWF method. It is shown that the main toughening mechanism in HDPE/TPS blends is shear-yielding. This article demonstrates that stiff, low diameter TPS particles reduce shear band formation and consequently decrease the resistance to crack propagation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Impact of the p53 status of tumor cells on extrinsic and intrinsic apoptosis signaling.

Science.gov (United States)

Wachter, Franziska; Grunert, Michaela; Blaj, Cristina; Weinstock, David M; Jeremias, Irmela; Ehrhardt, Harald

2013-04-17

The p53 protein is the best studied target in human cancer. For decades, p53 has been believed to act mainly as a tumor suppressor and by transcriptional regulation. Only recently, the complex and diverse function of p53 has attracted more attention. Using several molecular approaches, we studied the impact of different p53 variants on extrinsic and intrinsic apoptosis signaling. We reproduced the previously published results within intrinsic apoptosis induction: while wild-type p53 promoted cell death, different p53 mutations reduced apoptosis sensitivity. The prediction of the impact of the p53 status on the extrinsic cell death induction was much more complex. The presence of p53 in tumor cell lines and primary xenograft tumor cells resulted in either augmented, unchanged or reduced cell death. The substitution of wild-type p53 by mutant p53 did not affect the extrinsic apoptosis inducing capacity. In summary, we have identified a non-expected impact of p53 on extrinsic cell death induction. We suggest that the impact of the p53 status of tumor cells on extrinsic apoptosis signaling should be studied in detail especially in the context of therapeutic approaches that aim to restore p53 function to facilitate cell death via the extrinsic apoptosis pathway.

Control of the interfacial reactions in Nb-toughened MoSi2

International Nuclear Information System (INIS)

Shaw, L.; Abbaschian, R.

1993-01-01

Toughening of MoSi 2 for high-temperature applications can be achieved by incorporating ductile refractory-metal reinforcements, provided that a coating is applied to prevent interdiffusion and reaction between the matrix and the reinforcements. In the present study, three different coating techniques for applying a thin Al 2 O 3 film on Nb reinforcements as a diffusion barrier have been studied. The techniques consisted of (1) sol-gel coating; (2) physical vapor deposition (PVD); (3) hot dipping in molten Al, followed by anodizing Al to form Al 2 O 3 . The processing parameters for the techniques were evaluated and the effectiveness of each coating as a diffusion barrier was assessed. For the present MoSi 2 matrix which contains SiO 2 , PVD coatings provided the most effective diffusion barrier for processing MoSi 2 /Nb composites

Intrinsic and Extrinsic Motivation among Collegiate Instrumentalists

Science.gov (United States)

Diaz, Frank M.

2010-01-01

The purpose of this study was to gather and compare information on measures of intrinsic and extrinsic motivation among instrumentalists enrolled in collegiate ensembles. A survey instrument was developed to gather information concerning demographic data and responses to questions on motivational preference. Participants were undergraduate and…

Distinct neural control of intrinsic and extrinsic muscles of the hand during single finger pressing.

Science.gov (United States)

Dupan, Sigrid S G; Stegeman, Dick F; Maas, Huub

2018-06-01

Single finger force tasks lead to unintended activation of the non-instructed fingers, commonly referred to as enslaving. Both neural and mechanical factors have been associated with this absence of finger individuality. This study investigates the amplitude modulation of both intrinsic and extrinsic finger muscles during single finger isometric force tasks. Twelve participants performed single finger flexion presses at 20% of maximum voluntary contraction, while simultaneously the electromyographic activity of several intrinsic and extrinsic muscles associated with all four fingers was recorded using 8 electrode pairs in the hand and two 30-electrode grids on the lower arm. The forces exerted by each of the fingers, in both flexion and extension direction, were recorded with individual force sensors. This study shows distinct activation patterns in intrinsic and extrinsic hand muscles. Intrinsic muscles exhibited individuation, where the agonistic and antagonistic muscles associated with the instructed fingers showed the highest activation. This activation in both agonistic and antagonistic muscles appears to facilitate finger stabilisation during the isometric force task. Extrinsic muscles show an activation independent from instructed finger in both agonistic and antagonistic muscles, which appears to be associated with stabilisation of the wrist, with an additional finger-dependent modulation only present in the agonistic extrinsic muscles. These results indicate distinct muscle patterns in intrinsic and extrinsic hand muscles during single finger isometric force pressing. We conclude that the finger specific activation of intrinsic muscles is not sufficient to fully counteract enslaving caused by the broad activation of the extrinsic muscles. Copyright © 2018 Elsevier B.V. All rights reserved.

Three-dimensional deformation mapping of Mode I interlaminar crack extension in particle-toughened interlayers

International Nuclear Information System (INIS)

Borstnar, G.; Gillard, F.; Mavrogordato, M.N.; Sinclair, I.; Spearing, S.M.

2016-01-01

This paper presents the first use of Digital Volume Correlation (DVC) on Carbon Fibre Reinforced Plastics (CFRPs) to quantify the strain fields ahead of a Mode I delamination. DVC is a relatively novel tool that can be used to measure displacements and strains occurring inside materials under load. In conjunction with Computed Tomography (CT), the technique has been applied to porous materials, with results providing strain data for validation of Finite Element (FE) models. However, the application of the technique to laminated materials has been limited, with studies often requiring fiducial markings required for volume correlation. In this work, crack propagation steps were captured at a 325 nm voxel resolution using Synchrotron Radiation Computed Tomography (SRCT). The material systems investigated featured different crack bridging mechanisms such as; particle-bridges, resin ligaments, and fibre-bridges. An assessment of noise and sub-volume size on the strain measurement determined that the optimal sub-volume size was 150 voxels with 50% overlap. This provided a spatial resolution of 48.8 μm for strain and a corresponding strain resolution ranging between 220 and 690 με for the repeated reference scans. A rigid body translation study confirmed that specimen movements perpendicular to the fibre orientation support the ‘real’ physical displacements. However, along the fibre direction, the correlation was poor, with correct displacements being detected only within the particle-toughened interlayers. The study demonstrates that strain measurements can be made perpendicular to the fibre direction across the interlayer, which could be used to validate future FE models of these poorly understood particle-toughened interlayers.

Extrinsic Fabry-Perot ultrasonic detector

Science.gov (United States)

Kidwell, J. J.; Berthold, John W., III

1996-10-01

We characterized the performance of a commercial fiber optic extrinsic Fabry-Perot interferometer for use as an ultrasonic sensor, and compared the performance with a standard lead zirconate titanate (PZT) detector. The interferometer was unstabilized. The results showed that the fiber sensor was about 12 times less sensitive than the PZT detector. Ultrasonic frequency response near 100 kHz was demonstrated. We describe the design of the fiber sensor, the details of the tests performed, and potential applications.

Intrinsic and extrinsic labeling for studies of manganese absorption in humans

International Nuclear Information System (INIS)

Davidsson, L.; Cederblad, A.; Hagebo, E.; Loennerdal, B.S.; Sandstroem, B.

1988-01-01

A dual-radioisotope method was used to simultaneously study whole-body manganese retention from a chicken liver based meal intrinsically labeled with 54 Mn and extrinsically labeled with 52 Mn. Manganese retention was monitored in a sensitive whole-body counter during approximately 30 d in six young adult women. Both radioisotopes were retained to a similar degree and excreted at identical rates. Retention at d 5 was 14.4 +/- 10.3 and 14.0 +/- 9.9% while retention at d 10 was 5.0 +/- 3.1 and 5.0 +/- 3.0% (X +/- SD) for 54 Mn and 52 Mn, respectively. From these results we conclude that the intrinsic and extrinsic Mn isotopes did form a common pool before absorption. The results can therefore be regarded as a direct validation of the use of extrinsic labeling for studies of Mn retention for estimating Mn absorption in man

Ultrasonographic evaluation of normal extrinsic and intrinsic carpal ligaments: preliminary experience

International Nuclear Information System (INIS)

Boutry, Nathalie; Lapegue, Franck; Demondion, Xavier; Masi, Laetitia; Cotten, Anne; Claret, Antoine

2005-01-01

To determine normal anatomy of extrinsic and intrinsic carpal ligaments at ultrasonography (US). In the first part of the study, two musculoskeletal radiologists retrospectively reviewed in consensus the photographs of anatomic sections and dissections derived from 20 cadaveric wrists. This cadaveric study gave the two readers the opportunity to learn the anatomy and orientation of the various extrinsic and intrinsic carpal ligaments and, thus, to develop a US protocol to facilitate the recognition of each carpal ligament. In the second part of the study, these two radiologists prospectively and independently evaluated the visibility of extrinsic and intrinsic carpal ligaments in 30 wrists of volunteers, using the same US protocol. With regard to extrinsic carpal ligaments, the radioscaphocapitate ligament (partially visible, 38%; completely visible, 62%), the radiolunotriquetral ligament (partially visible, 27%; completely visible, 73%), the palmar ulnotriquetral ligament (partially visible, 12%; completely visible, 88%), and the dorsal radiotriquetral ligament (partially visible, 7%; completely visible, 93%) were visualized at US. The dorsal ulnotriquetral ligament (partially visible, 21%; completely visible, 74%), the ulnolunate ligament (partially visible, 5%; completely visible, 70%), and the radial collateral ligament (partially visible, 18%; completely visible, 12%) were more difficult to recognize. The radioscapholunate ligament was never seen. With regard to intrinsic carpal ligaments, the dorsal (partially visible, 11%; completely visible, 89%) and palmar (partially visible, 38%; completely visible, 62%) scaphotriquetral ligaments as well as the dorsal scapholunate ligament (partially visible, 3%; completely visible, 97%) were visualized at US. The dorsal lunotriquetral ligament (partially visible, 39%; completely visible, 61%) and the palmar scapholunate ligaments (partially visible, 12%; completely visible, 81%) were more difficult to recognize. US may

Are competition and extrinsic motivation reliable predictors of academic cheating?

Directory of Open Access Journals (Sweden)

Gábor eOrosz

2013-02-01

Full Text Available Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356. Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes towards self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

Are competition and extrinsic motivation reliable predictors of academic cheating?

Science.gov (United States)

Orosz, Gábor; Farkas, Dávid; Roland-Lévy, Christine

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast, extrinsic motivation had no significant effect. Indirect positive influence on cheating, based on some characteristics of hypercompetition, was also found, whereas attitudes toward self-developmental competition had a mediated negative influence. Neither constructive nor destructive competitive classroom climate had a significant impact on academic dishonesty. Acceptance of cheating and guilt has significant and direct effect on self-reported cheating. In comparison with them, the effects of motivational and competition-related variables are relatively small, even negligible. These results suggest that extrinsic motivation and competition are not amongst the most reliable predictors of academic cheating behavior.

Near-UV laser treatment of extrinsic dental enamel stains.

Science.gov (United States)

Schoenly, J E; Seka, W; Featherstone, J D B; Rechmann, P

2012-04-01

The selective ablation of extrinsic dental enamel stains using a 400-nm laser is evaluated at several fluences for completely removing stains with minimal damage to the underlying enamel. A frequency-doubled Ti:sapphire laser (400-nm wavelength, 60-nanosecond pulse duration, 10-Hz repetition rate) was used to treat 10 extracted human teeth with extrinsic enamel staining. Each tooth was irradiated perpendicular to the surface in a back-and-forth motion over a 1-mm length using an ∼300-µm-diam 10th-order super-Gaussian beam with fluences ranging from 0.8 to 6.4 J/cm(2) . Laser triangulation determined stain depth and volume removed by measuring 3D surface images before and after irradiation. Scanning electron microscopy evaluated the surface roughness of enamel following stain removal. Fluorescence spectroscopy measured spectra of unbleached and photobleached stains in the spectral range of 600-800 nm. Extrinsic enamel stains are removed with laser fluences between 0.8 and 6.4 J/cm(2) . Stains removed on sound enamel leave behind a smooth enamel surface. Stain removal in areas with signs of earlier cariogenic acid attacks resulted in isolated and randomly located laser-induced, 50-µm-diam enamel pits. These pits contain 0.5-µm diam, smooth craters indicative of heat transfer from the stain to the enamel and subsequent melting and water droplet ejection. Ablation stalling of enamel stains is typically observed at low fluences (Laser ablation of extrinsic enamel stains at 400 nm is observed to be most efficient above 3 J/cm(2) with minimal damage to the underlying enamel. Unsound underlying enamel is also observed to be selectively removed after irradiation. Copyright © 2012 Wiley Periodicals, Inc.

Intrinsic and Extrinsic Motivational Orientations in the Classroom: Age Differences and Academic Correlates

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Lepper, Mark R.; Corpus, Jennifer Henderlong; Iyengar, Sheena S.

2005-01-01

Age differences in intrinsic and extrinsic motivation and the relationships of each to academic outcomes were examined in an ethnically diverse sample of 797 3rd-grade through 8th-grade children. Using independent measures, the authors found intrinsic and extrinsic motivation to be only moderately correlated, suggesting that they may be largely…

Perceived extrinsic mortality risk and reported effort in looking after health: testing a behavioral ecological prediction.

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Pepper, Gillian V; Nettle, Daniel

2014-09-01

Socioeconomic gradients in health behavior are pervasive and well documented. Yet, there is little consensus on their causes. Behavioral ecological theory predicts that, if people of lower socioeconomic position (SEP) perceive greater personal extrinsic mortality risk than those of higher SEP, they should disinvest in their future health. We surveyed North American adults for reported effort in looking after health, perceived extrinsic and intrinsic mortality risks, and measures of SEP. We examined the relationships between these variables and found that lower subjective SEP predicted lower reported health effort. Lower subjective SEP was also associated with higher perceived extrinsic mortality risk, which in turn predicted lower reported health effort. The effect of subjective SEP on reported health effort was completely mediated by perceived extrinsic mortality risk. Our findings indicate that perceived extrinsic mortality risk may be a key factor underlying SEP gradients in motivation to invest in future health.

A reactive polystyrene-block-polyisoprene star copolymer as a toughening agent in an epoxy thermoset

KAUST Repository

Francis, Raju

2015-12-29

© 2015 Springer-Verlag Berlin Heidelberg A polystyrene-block-polyisoprene ((PS-b-PI)3) star polymer was synthesized by photochemical reversible addition fragmentation chain transfer (RAFT) polymerization. The obtained star polymer was epoxidized and used as a toughening agent in an epoxy thermoset. The incorporation of the epoxidized star polymer resulted in the formation of nanostructures and it was fixed by a crosslinking reaction. The formation of nanostructures in the thermosets follows the mechanism of reaction-induced microphase separation. The mechanical properties such as toughness and tensile strength were considerably increased due to the nanostructures formed by reactive blending.

Crystallography and Interphase Boundary of Martensite and Bainite in Steels

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Furuhara, Tadashi; Chiba, Tadachika; Kaneshita, Takeshi; Wu, Huidong; Miyamoto, Goro

2017-06-01

Grain refinements in lath martensite and bainite structures are crucial for strengthening and toughening of high-strength structural steels. Clearly, crystallography of transformation plays an important role in determining the "grain" sizes in these structures. In the present study, crystallography and intrinsic boundary structure of martensite and bainite are described. Furthermore, various extrinsic factors affecting variant selection and growth kinetics, such as elastic/plastic strain and alloying effects on interphase boundary migration, are discussed.

The relationship between primary school teachers extrinsic ...

African Journals Online (AJOL)

The study investigated the relationship between primary school teacher's extrinsic motivation and pupils' academic performance in Cross river State, Nigeria. Ex Post Facto research design was adopted for the study. The population of the study consisted of 17,221 teachers and 68,201 Primary Six Pupils in the three ...

Life Goals and Well-Being: Are Extrinsic Aspirations Always Detrimental to Well-Being?

Directory of Open Access Journals (Sweden)

Ingrid Brdar

2009-12-01

Full Text Available Past research has revealed that relative importance a person places on extrinsic life goals as oposed to intrinsic ones is related to lower well-being. But sometimes it is more important why a goal is being pursued than the content of the goal. Materialistic aspirations will not decrease people's well-being if they help them to achieve basic financial security or some intrinsic goals. On the other hand, if social comparison or seeking power drives extrinsic orientation, these aspirations may be detrimental for well-being, since they do not satisfy satisfy our basic psychological needs. Research from Croatia and other, less rich countries suggest that extrinsic aspirations are not necessarily deterimental but may even contribute to well-being. This finding suggests that various factors can moderate the relationship between aspirations and well-being. Intrinsic life goals may probably be affordable only for people who are well off enough. The meaning of financial success in transitional and poor countries may not necesseraly be associated with purchase and consumption. On the contrary, it may bring opportunities and possibilities of self-expression and self-growth. Individualistic societies allow individuals to pursue their intrinsic goals while collectivistic cultures stress extrinsic ones. Although this extrinsic orientation may detract their well-being, the sense of individual well-being may not be as important to them as the survival of the group they belong to or so called social well-being.

Intrinsic and Extrinsic Interlay Factors in Saudi Graduate Students' Perception of Performance and Success

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Maguire, Richard K.; Corbin, Thomas Philip, Jr.

2015-01-01

The natural symbiotic relationship between intrinsic and extrinsic factors and how they contribute to student success is undeniable. A plethora of work including self-determination, attribution, and social cognitive theories speak about academic achievement by students having a reciprocity relationship between the extrinsic factors that underline…

Effector-independent motor sequence representations exist in extrinsic and intrinsic reference frames.

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Wiestler, Tobias; Waters-Metenier, Sheena; Diedrichsen, Jörn

2014-04-02

Many daily activities rely on the ability to produce meaningful sequences of movements. Motor sequences can be learned in an effector-specific fashion (such that benefits of training are restricted to the trained hand) or an effector-independent manner (meaning that learning also facilitates performance with the untrained hand). Effector-independent knowledge can be represented in extrinsic/world-centered or in intrinsic/body-centered coordinates. Here, we used functional magnetic resonance imaging (fMRI) and multivoxel pattern analysis to determine the distribution of intrinsic and extrinsic finger sequence representations across the human neocortex. Participants practiced four sequences with one hand for 4 d, and then performed these sequences during fMRI with both left and right hand. Between hands, these sequences were equivalent in extrinsic or intrinsic space, or were unrelated. In dorsal premotor cortex (PMd), we found that sequence-specific activity patterns correlated higher for extrinsic than for unrelated pairs, providing evidence for an extrinsic sequence representation. In contrast, primary sensory and motor cortices showed effector-independent representations in intrinsic space, with considerable overlap of the two reference frames in caudal PMd. These results suggest that effector-independent representations exist not only in world-centered, but also in body-centered coordinates, and that PMd may be involved in transforming sequential knowledge between the two. Moreover, although effector-independent sequence representations were found bilaterally, they were stronger in the hemisphere contralateral to the trained hand. This indicates that intermanual transfer relies on motor memories that are laid down during training in both hemispheres, but preferentially draws upon sequential knowledge represented in the trained hemisphere.

Extrinsic versus intrinsic factors in the decline and extinction of Australian marsupials.

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Fisher, Diana O; Blomberg, Simon P; Owens, Ian P F

2003-09-07

Recent attempts to explain the susceptibility of vertebrates to declines worldwide have largely focused on intrinsic factors such as body size, reproductive potential, ecological specialization, geographical range and phylogenetic longevity. Here, we use a database of 145 Australian marsupial species to test the effects of both intrinsic and extrinsic factors in a multivariate comparative approach. We model five intrinsic (body size, habitat specialization, diet, reproductive rate and range size) and four extrinsic (climate and range overlap with introduced foxes, sheep and rabbits) factors. We use quantitative measures of geographical range contraction as indices of decline. We also develop a new modelling approach of phylogenetically independent contrasts combined with imputation of missing values to deal simultaneously with phylogenetic structuring and missing data. One extrinsic variable-geographical range overlap with sheep-was the only consistent predictor of declines. Habitat specialization was independently but less consistently associated with declines. This suggests that extrinsic factors largely determine interspecific variation in extinction risk among Australian marsupials, and that the intrinsic factors that are consistently associated with extinction risk in other vertebrates are less important in this group. We conclude that recent anthropogenic changes have been profound enough to affect species on a continent-wide scale, regardless of their intrinsic biology.

Effects of a Baking Soda Gum on extrinsic dental stain: results of a longitudinal 4-week assessment.

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Soparkar, P; Newman, M B

2001-07-01

An evaluation of the effects of ARM & HAMMER DENTAL CARE The Baking Soda Gum (AHDC) on extrinsic dental stain was made in 48 subjects presenting with measurable extrinsic stain. The subjects were randomized to use either the baking soda gum or a non-baking soda placebo gum for 20 minutes twice daily after lunch and dinner while brushing once daily. The procedure of limited brushing was chosen to simulate the level of hygiene normally practiced by participants entering a clinical study. After 4 weeks, the reduction in measurable extrinsic stain in the baking soda gum group was statistically significant (P = .0044) relative to baseline. Statistical analysis of the placebo gum group revealed no significant change in extrinsic stain from baseline. The magnitude of the unadjusted longitudinal reduction in extrinsic stain in the baking soda gum group was 29.7% at 4 weeks.

Extrinsic Motivators Affecting Fourth-Grade Students' Interest and Enrollment in an Instrumental Music Program

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Vasil, Martina

2013-01-01

The purpose of this study was to investigate fourth-grade students' extrinsic motivators for joining and continuing in a school instrumental music program. Three research questions were investigated: (a) What extrinsic motivators have influenced fourth-grade students' initial interest and continuing participation in an instrumental music program?…

Distinguishing subtypes of extrinsic motivation among people with mild to borderline intellectual disability

OpenAIRE

Frielink, N.; Schuengel, C.; Embregts, P.J.C.M.

2017-01-01

Background According to self-determination theory, motivation is ordered in types, including amotivation, extrinsic motivation and intrinsic motivation. Self-determination theory defines four subtypes of extrinsic motivation: external motivation, introjected motivation, identified motivation and integrated motivation. Although it has been argued theoretically that the different types of motivation are universally applicable, Reid et al. (2009) proposed a dichotomy of broad subtypes of extrins...

Toughening modification of poly(butylene terephthalate)/poly(ethylene terephthalate) blends by an epoxy-functionalized elastomer

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Zhang, Weizhou; Wang, Kai; Yan, Wei; Guo, Weihong

2017-10-01

New toughened poly(butylene terephthalate) (PBT)/poly(ethylene terephthalate) (PET) (40/60 wt%) blends were obtained by melting with Glycidyl methacrylate grafted poly(ethylene octane) copolymer (POE-g-GMA), varying the POE-g-GMA content up to 20 wt%, in a twin-screw extruder, followed by injection molding. The influence of POE-g-GMA on the properties of the PBT/PET blends was investigated by mechanical testing, Fourier transform infrared (FT-IR) analysis, gel fractions analysis, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and scanning electronic microscopy (SEM). The mechanical testing results indicated that the incorporation of POE-g-GMA led to increases in the notched impact strength and decreases in the tensile strength, flexural strength, and flexural modulus. When POE-g-GMA content reached 20 wt%, the notched impact strength (8.0 kJ m-2) was achieved for the PBT/PET/POE-g-GMA blends. FT-IR results proved that some PBT/PET/POE-g-GMA copolymers were produced, which improved the compatibility between POE-g-GMA and the PBT/PET matrix. The extent of crosslinking was observed by gel fraction measurements. DMA results further testified chain-extending and micro-crosslink reactions occurred between POE-g-GMA and PBT/PET blends. In addition, the reactions induced by POE-g-GMA affected the crystallization behavior of PBT/PET blends obviously, as observed from DSC results. By means of SEM observation of the impact fracture surface morphology, and the discussion of the micro-crosslink reaction process between the epoxide-containing elastomers and PBT/PET matrix, the toughening mechanism was proposed to be taken into account the shear yielding of PBT/PET matrix and cavitation of elastomer particles.

The fragmented self: imbalance between intrinsic and extrinsic self-networks in psychotic disorders.

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Ebisch, Sjoerd J H; Aleman, André

2016-08-01

Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging evidence for disrupted communication between neural networks subserving the so-called intrinsic self and extrinsic self. This disruption might be mainly caused by impaired integrity of key brain hubs. The intrinsic self has been associated with cortical midline structures involved in self-referential processing, autobiographical memory, and emotional evaluation. Additionally, we highlight central aspects of the extrinsic self in its interaction with the environment using sensorimotor networks, including self-experience in sensation and actions. A deficient relationship between these self-aspects because of disrupted between-network interactions offers a framework to explain core clinical features of psychotic disorders. In particular, we show how relative isolation and reduced modularity of networks subserving intrinsic and extrinsic self-processing might trigger the emergence of hallucinations and delusions, and why patients with psychosis typically have difficulties with self-other relationships and do not recognise mental problems. Copyright © 2016 Elsevier Ltd. All rights reserved.

Extrinsic Contribution and Instability Properties in Lead-Based and Lead-Free Piezoceramics

Directory of Open Access Journals (Sweden)

José Eduardo García

2015-11-01

Full Text Available Piezoceramic materials generally exhibit a notable instability of their functional properties when they work under real external conditions. This undesirable effect, known as nonlinear behavior, is mostly associated with the extrinsic contribution to material response. In this article, the role of the ferroelectric domain walls’ motion in the nonlinear response in the most workable lead-based and lead-free piezoceramics is reviewed. Initially, the extrinsic origin of the nonlinear response is discussed in terms of the temperature dependence of material response. The influence of the crystallographic phase and of the phase boundaries on the material response are then reviewed. Subsequently, the impact of the defects created by doping in order to control the extrinsic contribution is discussed as a way of tuning material properties. Finally, some aspects related to the grain-size effect on the nonlinear response of piezoceramics are surveyed.

Consolidation power of extrinsic rewards: reward cues enhance long-term memory for irrelevant past events.

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Murayama, Kou; Kitagami, Shinji

2014-02-01

Recent research suggests that extrinsic rewards promote memory consolidation through dopaminergic modulation processes. However, no conclusive behavioral evidence exists given that the influence of extrinsic reward on attention and motivation during encoding and consolidation processes are inherently confounded. The present study provides behavioral evidence that extrinsic rewards (i.e., monetary incentives) enhance human memory consolidation independently of attention and motivation. Participants saw neutral pictures, followed by a reward or control cue in an unrelated context. Our results (and a direct replication study) demonstrated that the reward cue predicted a retrograde enhancement of memory for the preceding neutral pictures. This retrograde effect was observed only after a delay, not immediately upon testing. An additional experiment showed that emotional arousal or unconscious resource mobilization cannot explain the retrograde enhancement effect. These results provide support for the notion that the dopaminergic memory consolidation effect can result from extrinsic reward.

Process analysis using the concept of intrinsic and extrinsic exergy losses

International Nuclear Information System (INIS)

Chang Hsuan; Chuang, S.-C.

2003-01-01

This paper introduces a two-level idealization concept and decomposes the exergy losses of processing operations into the intrinsic part and the extrinsic part. The first level idealization is the reversible operation and the second level idealization is the thermodynamic equilibrium operation. The exergy losses arising from the deviations from the first level idealization only, caused by configuration constraints, are defined as the intrinsic exergy losses. The extra exergy losses which arise from further deviations from the second level idealization, caused by transport rate limitations, are defined as the extrinsic exergy losses. Demonstrated by several example cases of different complex levels, the analysis results can pinpoint what and where to focus on for improvements: (1) design configurations or transport rate limitations, and (2) the specific locations within the operations or processes. As an example, for a de-ethanizer, the improvement measures on configuration-related and transport rate-related design conditions result in a 11.42% reduction of overall column intrinsic exergy loss and a 81.74% reduction of total individual stage extrinsic exergy loss

Intrinsic and extrinsic mechanical properties related to the differentiation of mesenchymal stem cells.

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Lee, Jin-Ho; Park, Hun-Kuk; Kim, Kyung Sook

2016-05-06

Diverse intrinsic and extrinsic mechanical factors have a strong influence on the regulation of stem cell fate. In this work, we examined recent literature on the effects of mechanical environments on stem cells, especially on differentiation of mesenchymal stem cells (MSCs). We provide a brief review of intrinsic mechanical properties of single MSC and examined the correlation between the intrinsic mechanical property of MSC and the differentiation ability. The effects of extrinsic mechanical factors relevant to the differentiation of MSCs were considered separately. The effect of nanostructure and elasticity of the matrix on the differentiation of MSCs were summarized. Finally, we consider how the extrinsic mechanical properties transfer to MSCs and then how the effects on the intrinsic mechanical properties affect stem cell differentiation. Copyright © 2015 Elsevier Inc. All rights reserved.

No evidence for extrinsic post-zygotic isolation in a wild Saccharomyces yeast system.

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Charron, Guillaume; Landry, Christian R

2017-06-01

Although microorganisms account for the largest fraction of Earth's biodiversity, we know little about how their reproductive barriers evolve. Sexual microorganisms such as Saccharomyces yeasts rapidly develop strong intrinsic post-zygotic isolation, but the role of extrinsic isolation in the early speciation process remains to be investigated. We measured the growth of F 1 hybrids between two incipient species of Saccharomyces paradoxus to assess the presence of extrinsic post-zygotic isolation across 32 environments. More than 80% of hybrids showed either partial dominance of the best parent or over-dominance for growth, revealing no fitness defects in F 1 hybrids. Extrinsic reproductive isolation therefore likely plays little role in limiting gene flow between incipient yeast species and is not a requirement for speciation. © 2017 The Author(s).

Shifting the Sun: Solar Spectral Conversion and Extrinsic Sensitization in Natural and Artificial Photosynthesis.

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Wondraczek, Lothar; Tyystjärvi, Esa; Méndez-Ramos, Jorge; Müller, Frank A; Zhang, Qinyuan

2015-12-01

Solar energy harvesting is largely limited by the spectral sensitivity of the employed energy conversion system, where usually large parts of the solar spectrum do not contribute to the harvesting scheme, and where, of the contributing fraction, the full potential of each photon is not efficiently used in the generation of electrical or chemical energy. Extrinsic sensitization through photoluminescent spectral conversion has been proposed as a route to at least partially overcome this problem. Here, we discuss this approach in the emerging context of photochemical energy harvesting and storage through natural or artificial photosynthesis. Clearly contrary to application in photovoltaic energy conversion, implementation of solar spectral conversion for extrinsic sensitization of a photosynthetic machinery is very straightforward, and-when compared to intrinsic sensitization-less-strict limitations with regard to quantum coherence are seen. We now argue the ways in which extrinsic sensitization through photoluminescent spectral converters will-and will not-play its role in the area of ultra-efficient photosynthesis, and also illustrate how such extrinsic sensitization requires dedicated selection of specific conversion schemes and design strategies on system scale.

Creating Rich Portraits: A Mixed-Methods Approach to Understanding Profiles of Intrinsic and Extrinsic Motivations

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Corpus, Jennifer Henderlong; Wormington, Stephanie V.; Haimovitz, Kyla

2016-01-01

A person-centered, mixed-methods approach (self-report surveys, semistructured interviews, school records) was used to characterize and evaluate profiles of intrinsic and extrinsic motivations among 243 third- through eighth-grade students. Cluster analysis suggested four distinct profiles: high quantity (high intrinsic, high extrinsic), primarily…

Impact of Mentoring on Perceived Adequacy of Extrinsic ...

African Journals Online (AJOL)

This study examined the impact of informal mentoring on perceived adequacy of extrinsic organizational rewards such as pay, promotion and fringe benefit. Data were obtained from 161 employees through a survey of a public health organisation in south-western Nigeria. Hierarchical regression analysis revealed that ...

CT-semiotics and clinical aspects of extrinsic allergic alveolitis

International Nuclear Information System (INIS)

Skrynnikova, I.P.; Momot, N.V.; Vakulenko, I.P.; Tanasichuk-Gazhieva, N.V

2003-01-01

Extrinsic allergic alveolitis can be a difficult diagnostic problem. The comparison of the results of CT research with the clinical immunological and morphological data allowed to define the forms and diagnose the characteristic symptoms of the disease

Beyond the Big Five: the role of extrinsic life aspirations in compulsive buying.

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Otero-López, José M; Villardefrancos Pol, Estíbaliz; Castro Bolaño, Cristina

2017-11-01

The integration of units of differing natures which are found in different parts of some multilevel personality models is one of the most thought-provoking paths in contemporary research. In the field of compulsive buying, little is known about the interrelationships between the comparative and stable units such as personality traits (basic tendencies or Level I units) and goals (a kind of middle-level unit) which are more related to motivational processes and intentions governing people’s behavior. Self-reporting measures of compulsive buying, Big Five personality traits, and extrinsic life aspirations were administered to a general population sample consisting of 2,159 participants aged 15 to 65 (48.1% males; Mage= 35.4, SD= 13.24). Our results confirmed statistically significant associations with compulsive buying for the traits as well as the extrinsic goals. Furthermore, an important relationship between both levels in personality – traits vs . extrinsic life aspirations – was found. Finally, extrinsic life aspirations (specially, image, popularity, and conformity) contribute to the potentiation of the prediction of compulsive buying beyond the Five Factor Model. Current findings emphasize the advisability of considering both levels in personality, traits and middle-level units like life aspirations, not only in the prediction of compulsive buying, but also as potential targets for preventive and treatment programs.

Role of extrinsic arbuscular mycorrhizal fungi in heavy metal-contaminated wetlands with various soil moisture levels.

Science.gov (United States)

Zheng, S; Wang, C; Shen, Z; Quan, Y; Liu, X

2015-01-01

This study presents an efficient heavy metal (HM) control method in HM-contaminated wetlands with varied soil moisture levels through the introduction of extrinsic arbuscular mycorrhizal fungi (AMF) into natural wetland soil containing indigenous AMF species. A pot culture experiment was designed to determine the effect of two soil water contents (5-8% and 25-30%), five extrinsic AMF inoculants (Glomus mosseae, G. clarum, G. claroideum, G. etunicatum, and G. intraradices), and HM contamination on root colonization, plant growth, and element uptake of common reed (Phragmites australis (Cav.) Trin. ex Steudel) plantlets in wetland soils. This study showed the prevalence of mycorrhizae in the roots of all P. australis plantlets, regardless of extrinsic AMF inoculations, varied soil moisture or HM levels. It seems that different extrinsic AMF inoculations effectively lowered HM concentrations in the aboveground tissues of P. australis at two soil moisture levels. However, metal species, metal concentrations, and soil moisture should also be very important factors influencing the elemental uptake performance of plants in wetland ecosystems. Besides, the soil moisture level significantly influenced plant growth (including height, and shoot and root dry weight (DW)), and extrinsic AMF inoculations differently affected shoot DW.

Inter-subject Functional Correlation Reveal a Hierarchical Organization of Extrinsic and Intrinsic Systems in the Brain.

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Ren, Yudan; Nguyen, Vinh Thai; Guo, Lei; Guo, Christine Cong

2017-09-07

The brain is constantly monitoring and integrating both cues from the external world and signals generated intrinsically. These extrinsically and intrinsically-driven neural processes are thought to engage anatomically distinct regions, which are thought to constitute the extrinsic and intrinsic systems of the brain. While the specialization of extrinsic and intrinsic system is evident in primary and secondary sensory cortices, a systematic mapping of the whole brain remains elusive. Here, we characterized the extrinsic and intrinsic functional activities in the brain during naturalistic movie-viewing. Using a novel inter-subject functional correlation (ISFC) analysis, we found that the strength of ISFC shifts along the hierarchical organization of the brain. Primary sensory cortices appear to have strong inter-subject functional correlation, consistent with their role in processing exogenous information, while heteromodal regions that attend to endogenous processes have low inter-subject functional correlation. Those brain systems with higher intrinsic tendency show greater inter-individual variability, likely reflecting the aspects of brain connectivity architecture unique to individuals. Our study presents a novel framework for dissecting extrinsically- and intrinsically-driven processes, as well as examining individual differences in brain function during naturalistic stimulation.

Acceleration of vascularized bone tissue-engineered constructs in a large animal model combining intrinsic and extrinsic vascularization.

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Weigand, Annika; Beier, Justus P; Hess, Andreas; Gerber, Thomas; Arkudas, Andreas; Horch, Raymund E; Boos, Anja M

2015-05-01

During the last decades, a range of excellent and promising strategies in Bone Tissue Engineering have been developed. However, the remaining major problem is the lack of vascularization. In this study, extrinsic and intrinsic vascularization strategies were combined for acceleration of vascularization. For optimal biomechanical stability of the defect site and simplifying future transition into clinical application, a primary stable and approved nanostructured bone substitute in clinically relevant size was used. An arteriovenous (AV) loop was microsurgically created in sheep and implanted, together with the bone substitute, in either perforated titanium chambers (intrinsic/extrinsic) for different time intervals of up to 18 weeks or isolated Teflon(®) chambers (intrinsic) for 18 weeks. Over time, magnetic resonance imaging and micro-computed tomography (CT) analyses illustrate the dense vascularization arising from the AV loop. The bone substitute was completely interspersed with newly formed tissue after 12 weeks of intrinsic/extrinsic vascularization and after 18 weeks of intrinsic/extrinsic and intrinsic vascularization. Successful matrix change from an inorganic to an organic scaffold could be demonstrated in vascularized areas with scanning electron microscopy and energy dispersive X-ray spectroscopy. Using the intrinsic vascularization method only, the degradation of the scaffold and osteoclastic activity was significantly lower after 18 weeks, compared with 12 and 18 weeks in the combined intrinsic-extrinsic model. Immunohistochemical staining revealed an increase in bone tissue formation over time, without a difference between intrinsic/extrinsic and intrinsic vascularization after 18 weeks. This study presents the combination of extrinsic and intrinsic vascularization strategies for the generation of an axially vascularized bone substitute in clinically relevant size using a large animal model. The additional extrinsic vascularization promotes tissue

Modelling of Extrinsic Fiber Optic Sagnac Ultrasound Interferometer ...

African Journals Online (AJOL)

Ultrasonic waves are used extensively in nondestructive testing both for characterization of material properties, in this paper, we describe a fiber optic sensor suitable for detection of ultrasonic waves. This sensor is based on an extrinsic fiber optic sagnac interferometer. The proposed sensor model can act as a conventional ...

Intrinsic and extrinsic motivational orientations in the competitive context: an examination of person-situation interactions.

Science.gov (United States)

Abuhamdeh, Sami; Csikszentmihalyi, Mihaly

2009-10-01

The current study examined Intrinsic Motivation Orientation and Extrinsic Motivation Orientation (Work Preference Inventory; Amabile, Hill, Hennessey, & Tighe, 1994) as potential trait-level moderators of the way Internet chess players responded to the intrinsic and extrinsic rewards of the chess games they played. On the basis of the defining characteristics of these 2 types of motivational orientations, we predicted that (a) Intrinsic Motivation Orientation would be associated with a stronger curvilinear relationship between challenge and enjoyment and (b) Extrinsic Motivation Orientation would be associated with a heightened affective responsivity to competitive outcome (i.e., winning vs. losing). Results supported the predictions. Implications of the findings are discussed.

A Novel Extraction Approach of Extrinsic and Intrinsic Parameters of InGaAs/GaN pHEMTs

Science.gov (United States)

2015-07-01

A Novel Extraction Approach of Extrinsic and Intrinsic Parameters of InGaAs/GaN pHEMTs Andong Huang1, 2, ZhengZhong2, 3, and Yongxin Guo2, 3...Suzhou Research Institute, Suzhou, China Abstract — A novel extraction approach of extrinsic and intrinsic parameters of InGaAs/GaN pHEMTs is...parameter error function. The extrinsic elements are optimized at multi-bias points and the intrinsic ones at specific bias points. Only broad ranges

Intrinsic, Transitional, and Extrinsic Morphological Factors Associated With Rupture of Intracranial Aneurysms.

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Ho, Allen L; Lin, Ning; Frerichs, Kai U; Du, Rose

2015-09-01

As diagnosis and treatment of unruptured intracranial aneurysms continues to increase, management principles remain largely based on size. This is despite mounting evidence that aneurysm location and other morphologic variables could play a role in predicting overall risk of rupture. Morphological parameters can be divided into 3 main groups, those that are intrinsic to the aneurysm, those that are extrinsic to the aneurysm, and those that involve both the aneurysm and surrounding vasculature (transitional). We present an evaluation of intrinsic, transitional, and extrinsic factors and their association with ruptured aneurysms. Using preoperative computed tomographic angiography, we generated 3-dimensional models of aneurysms and their surrounding vasculature with Slicer software. Using univariate and multivariate analyses, we examined the association of intrinsic, transitional, and extrinsic aspects of aneurysm morphology with rupture. Between 2005 and 2013, 227 cerebral aneurysms in 4 locations were evaluated/treated at a single institution, and computed tomographic angiographies of 218 patients (97 unruptured and 130 ruptured) were analyzed. Ruptured aneurysms analyzed were associated with clinical factors of absence of multiple aneurysms and history of no prior rupture, and morphologic factors of greater aspect ratio. On multivariate analysis, aneurysm rupture remained associated with history of no prior rupture, greater flow angle, greater daughter-daughter vessel angle, and smaller parent-daughter vessel angle. By studying the morphology of aneurysms and their surrounding vasculature, we identified several parameters associated with ruptured aneurysms that include intrinsic, transitional, and extrinsic factors of cerebral aneurysms and their surrounding vasculature.

Emotional competence and extrinsic emotion regulation directed toward an ostracized person.

Science.gov (United States)

Nozaki, Yuki

2015-12-01

Positive interpersonal relationships hinge on individuals' competence in regulating others' emotions as well as their own. Nevertheless, little is known about the relationship between emotional competence and specific interpersonal behaviors. In particular, it is unclear which situations require emotional competence for extrinsic emotion regulation and whether emotionally competent individuals actually attempt to regulate others' emotions. To clarify these issues, the current investigation examined the relationship between emotional competence and extrinsic emotion regulation directed toward an ostracized person. The results of Study 1 (N = 39) indicated that interpersonal emotional competence (competence related to others' emotions) was positively associated with participants' efforts to relieve the ostracized person's sadness. In Study 2 (N = 120), this relationship was moderated by the ostracized person's emotional expression. In particular, participants with high interpersonal emotional competence were more likely to attempt to regulate the sadness of ostracized individuals who expressed neutral affect. In contrast, when the ostracized person expressed sadness, there were no significant relationships between high or low interpersonal emotional competence and extrinsic emotion regulation behavior. These results offer novel insight into how emotionally competent individuals use their competence to benefit others. (c) 2015 APA, all rights reserved).

Ends, fundamental tones and capacity of minimal submanifolds via extrinsic comparison theory

DEFF Research Database (Denmark)

Gimeno, Vicent; Markvorsen, Steen

2015-01-01

We study the volume of extrinsic balls and the capacity of extrinsic annuli in minimal submanifolds which are properly immersed with controlled radial sectional curvatures into an ambient manifold with a pole. The key results are concerned with the comparison of those volumes and capacities with ...... with the corresponding entities in a rotationally symmetric model manifold. Using the asymptotic behavior of the volumes and capacities we then obtain upper bounds for the number of ends as well as estimates for the fundamental tone of the submanifolds in question....

The dark side of monetary incentive: how does extrinsic reward crowd out intrinsic motivation.

Science.gov (United States)

Ma, Qingguo; Jin, Jia; Meng, Liang; Shen, Qiang

2014-02-12

It was widely believed that incentives could effectively enhance the motivation of both students and employees. However, psychologists reported that extrinsic reward actually could undermine individuals' intrinsic motivation to a given interesting task, which challenged viewpoints from traditional incentive theories. Numerous studies have been carried out to test and explain the undermining effect; however, the neural basis of this effect is still elusive. Here, we carried out an electrophysiological study with a simple but interesting stopwatch task to explore to what extent the performance-based monetary reward undermines individuals' intrinsic motivation toward the task. The electrophysiological data showed that the differentiated feedback-related negativity amplitude toward intrinsic success failure divergence was prominently reduced once the extrinsic reward was imposed beforehand. However, such a difference was not observed in the control group, in which no extrinsic reward was provided throughout the experiment. Furthermore, such a pattern was not observed for P300 amplitude. Therefore, the current results indicate that extrinsic reward demotivates the intrinsic response of individuals toward success-failure outcome, which was reflected in the corresponding reduced motivational-related differentiated feedback-related negativity, but not in amplitude of P300.

Supertoughened Biobased Poly(lactic acid)-Epoxidized Natural Rubber Thermoplastic Vulcanizates: Fabrication, Co-continuous Phase Structure, Interfacial in Situ Compatibilization, and Toughening Mechanism.

Science.gov (United States)

Wang, Youhong; Chen, Kunling; Xu, Chuanhui; Chen, Yukun

2015-09-10

In the presence of dicumyl peroxide (DCP), biobased thermoplastic vulcanizates (TPVs) composed of poly(lactic acid) (PLA) and epoxidized natural rubber (ENR) were prepared through dynamic vulcanization. Interfacial in situ compatibilization between PLA and ENR phases was confirmed by Fourier transform infrared spectroscopy (FT-IR). A novel "sea-sea" co-continuous phase in the PLA/ENR TPVs was observed through scanning electron microscopy (SEM) and differed from the typical "sea-island" morphology that cross-linked rubber particles dispersed in plastic matrix. A sharp, brittle-ductile transition occurred with 40 wt % of ENR, showing a significantly improved impact strength of 47 kJ/m(2), nearly 15 times that of the neat PLA and 2.6 times that of the simple blend with the same PLA/ENR ratio. Gel permeation chromatography (GPC) and dynamic mechanical analysis (DMA) results suggested that a certain amount of DCP was consumed in the PLA phase, causing a slight cross-linking or branching of PLA molecules. the effects of various DCP contents on the impact property were investigated. The toughening mechanism under impact testing was researched, and the influence factors for toughening were discussed.

The Attitudes of Israeli Arab and Jewish High School Students towards Extrinsic and Intrinsic Values

Science.gov (United States)

Gross, Zehavit

2013-01-01

The aim of this research was to investigate the attitudes of Israeli Arab (n = 259) and Jewish (n = 259) high school students toward extrinsic and intrinsic values. A questionnaire, which consisted of eight value scales in two groups--extrinsic and intrinsic values--was administered. Participants were asked to state whether they agreed or…

Intrinsic and extrinsic motivations for healthful dietary change in African Americans.

Science.gov (United States)

Satia, Jessie A; Galanko, Joseph A

2007-01-01

To describe associations of intrinsic and extrinsic motivations for dietary change with participant characteristics and current diet among African Americans. Cross-sectional survey of 658 African American adults in North Carolina provided information on intrinsic (self-image and health concerns) and extrinsic (social influence) motivation scales, participant characteristics, and diet. Most respondents considered it important to change their diet for health reasons; fewer were motivated by self-image or social influence. Motivation scales were significantly associated with demographic, behavioral, and psychosocial characteristics and fat, but not fruit/vegetable consumption, after adjustment for covariates (Pextrinsic motives may improve the effectiveness of dietary interventions in African Americans.

Extrinsic attributes that influence parents' purchase of chocolate milk for their children.

Science.gov (United States)

Li, Xiaomeng E; Lopetcharat, Kannapon; Drake, MaryAnne

2014-07-01

The consumption of milk is essential for children's heath; and flavored milk, especially chocolate milk, is often purchased to increase children's milk consumption. However, the sugar content of chocolate milk has raised health concerns. As such, it is important to understand chocolate milk extrinsic attributes that influence parents' purchase decisions when they are purchasing chocolate milk for their children. The objective of this study was to determine the key extrinsic attributes for parents when they purchase chocolate milk for their children. An online survey with a conjoint analysis design, emotions questions, and Kano questionnaire that focused on chocolate milk was conducted targeting parents. Three hundred and twelve parents participated in the survey. Parents reported positive emotions including good, good natured, happy, loving, and satisfied when purchasing chocolate milk for their kids. Three segments of parents were identified with subtle but distinct differences in their key preferences for chocolate milk attributes for their children. Type of sweetener was the primary driver of choice for purchasing chocolate milk for children followed by fat content. Among sweetener types, natural noncaloric/nonnutritive sweeteners or sucrose were preferred over artificial sweeteners, and reduced fat was preferred over full fat or skim milk. Kano results revealed that reduced fat and sugar with an all natural label and added vitamins, minerals, and protein were attractive to the majority of parents when purchasing chocolate milk for their kids. Understanding the driving extrinsic attributes for parents when they purchase chocolate milk for their children will assist manufacturers to target extrinsic attributes that are attractive to parents for chocolate milk. This study established that sweetener type and fat content are the primary extrinsic attributes affecting parents purchase decisions when choosing chocolate milk for their children. Different segments of

The Effect Of Extrinsic Motivation On Adversity Quotient In Patients With HIV/AIDS

OpenAIRE

Nursalam, Nursalam; Misutarno, Misutarno; Puspitawati, Yulia Dewi

2017-01-01

Introduction: Patients with HIV/AIDS may have various types of psychological responses. It was very difficult situation for them. Difficulty can measured by using Adversity Quotient. As a nurse, we can give extrinsic motivation to bring back the patient HIV/AIDS’s quality of life. The objective of this study was to identify the presence effect of extrinsic motivation on Adversity Quotient in patients with HIV/AIDS in Infectious Disease Intermediateatery Treatment Unit, Dr. Soetomo Hospital, S...

The Effect of Extrinsic Motivation on Adversity Quotient in Patients with Hiv/aids

OpenAIRE

Nursalam, Nursalam; Misutarno, Misutarno; Puspitawati, Yulia Dewi

2008-01-01

Introduction: Patients with HIV/AIDS may have various types of psychological responses. It was very difficult situation for them. Difficulty can measured by using Adversity Quotient. As a nurse, we can give extrinsic motivation to bring back the patient HIV/AIDS’s quality of life. The objective of this study was to identify the presence effect of extrinsic motivation on Adversity Quotient in patients with HIV/AIDS in Infectious Disease Intermediateatery Treatment Unit, Dr. Soetomo Hospital, S...

Derivation of the extrinsic values of biological diversity from its intrinsic value and of both from the first principles of evolution.

Science.gov (United States)

White, Peter S

2013-12-01

Conservation ethics have been based on 2 philosophical value systems: extrinsic value (defined broadly to include all values that derive from something external to the thing valued) and intrinsic value. Valuing biological diversity on the basis of an extrinsic value system is problematic because measurement is often difficult; extrinsic value changes as spatial or temporal scales change; extrinsic value differs on the basis of external factors; some species have trivial or negative extrinsic values; and extrinsic value varies across human cultures and societies and with such factors as socioeconomic conditions, individual experiences, and educational backgrounds. Valuing biological diversity on the basis of an intrinsic value system also poses challenges because intrinsic value can be seen as a disguised form of human extrinsic value; intrinsic value is initially ambiguous as to which objects or characteristics of biological diversity are to being valued; all aspects of biological diversity (e.g., species and ecosystems) are transitory; species and ecosystems are not static concrete entities; and intrinsic value of one species is often in conflict with the intrinsic value of other species. Extrinsic and intrinsic value systems share a common origin, such that extrinsic values are always derived from intrinsic value and life mutely expresses both intrinsic and extrinsic values-these are derived from and are products of biological evolution. Probing the values that underlie conservation helps the community clearly articulate its aims. Derivación de los Valores Extrínsecos de la Biodiversidad a Partir de sus Valores Intrínsecos y de Ambos a Partir de los Primeros Principios de la Evolución. © 2013 Society for Conservation Biology.

Recovery of colonic transit following extrinsic nerve damage in rats.

Science.gov (United States)

Ridolfi, Timothy J; Tong, Wei Dong; Kosinski, Lauren; Takahashi, Toku; Ludwig, Kirk A

2011-06-01

Injury to pelvic sympathetic and parasympathetic nerves from surgical and obstetrical trauma has long been cited as a cause for abnormal colorectal motility in humans. Using a rat model, acute transaction of these extrinsic nerves has been shown to effect colorectal motility. The aim of this study is to determine in a rat model how transection of these extrinsic nerves affects colonic transit over time. Eighty-two Sprague-Dawley rats underwent placement of a tunneled catheter into the proximal colon. Bilateral hypogastric, pelvic nerves (HGN and PN) or both were transected in 66 rats. The remaining 16 rats received a sham operation. Colonic transit was evaluated at postoperative days (PODs) 1, 3, and 7 by injecting and calculating the geometric center (GC) of the distribution of (51)Cr after 3 h of propagation. At POD 1, transection of PNs significantly delayed colonic transit (GC = 4.9, p < 0.05), while transection of HGNs (GC = 8.5, p < 0.05) or transection of both nerves (GC = 7.8, p < 0.05) significantly accelerated colonic transit, when compared with sham operation (GC = 6.0). A significant trend toward recovery was noted in both the HGN and PN transection groups at POD 7. Damage to the extrinsic sympathetic and/or parasympathetic PNs affects colonic transit acutely. These changes in large bowel motor function normalize over time implicating a compensatory mechanism within the bowel itself.

Stochastic synchronization of neuronal populations with intrinsic and extrinsic noise.

KAUST Repository

Bressloff, Paul C

2011-05-03

We extend the theory of noise-induced phase synchronization to the case of a neural master equation describing the stochastic dynamics of an ensemble of uncoupled neuronal population oscillators with intrinsic and extrinsic noise. The master equation formulation of stochastic neurodynamics represents the state of each population by the number of currently active neurons, and the state transitions are chosen so that deterministic Wilson-Cowan rate equations are recovered in the mean-field limit. We apply phase reduction and averaging methods to a corresponding Langevin approximation of the master equation in order to determine how intrinsic noise disrupts synchronization of the population oscillators driven by a common extrinsic noise source. We illustrate our analysis by considering one of the simplest networks known to generate limit cycle oscillations at the population level, namely, a pair of mutually coupled excitatory (E) and inhibitory (I) subpopulations. We show how the combination of intrinsic independent noise and extrinsic common noise can lead to clustering of the population oscillators due to the multiplicative nature of both noise sources under the Langevin approximation. Finally, we show how a similar analysis can be carried out for another simple population model that exhibits limit cycle oscillations in the deterministic limit, namely, a recurrent excitatory network with synaptic depression; inclusion of synaptic depression into the neural master equation now generates a stochastic hybrid system.

Metabolism in rats of selenium from intrinsically and extrinsically labeled isolated soy protein

International Nuclear Information System (INIS)

Mason, A.C.; Weaver, C.M.

1986-01-01

Absorption, retention and tissue accumulation by rats of 75 Se from intrinsically labeled isolated soy protein were compared with utilization of 75 Se from the extrinsic sources of [ 75 Se]selenite, [ 75 Se]selenate or [ 75 Se]selenomethionine. Extrinsic sources of selenium were given by gavage or mixed with isolated soy protein. There were no differences in absorption and retention of 75 Se from intrinsically labeled soy diet compared to the three extrinsically labeled soy diets. Of the three extrinsic sources tested, 75 Se from selenate was better absorbed than from selenite or selenomethionine when incorporated into a soy diet. Absorption of 75 Se was significantly lower when given to animals in gavage solution than when mixed with soy diets. After a 14-d test period, retention of 75 Se was the same for all four soy diet groups. In gavaged groups, 75 Se from selenomethionine was retained to a greater extent than 75 Se from selenite. The liver, testes and kidney accumulated more 75 Se from the test meal than did the blood and lungs. In the testes more 75 Se from selenite and selenate was accumulated than from selenomethionine-labeled diets. Selenium absorption from the soy isolate source was very high (86-96%), indicating that, although soy does not normally contain high levels of selenium, the selenium present is well absorbed from this plant source

The effects of non-contingent extrinsic and intrinsic rewards on memory consolidation.

Science.gov (United States)

Nielson, Kristy A; Bryant, Ted

2005-07-01

Emotional and arousing treatments given shortly after learning enhance delayed memory retrieval in animal and human studies. Positive affect and reward induced prior to a variety of cognitive tasks enhance performance, but their ability to affect memory consolidation has not been investigated before. Therefore, we investigated the effects of a small, non-contingent, intrinsic or extrinsic reward on delayed memory retrieval. Participants (n=108) studied and recalled a list of 30 affectively neutral, imageable nouns. Experimental groups were then given either an intrinsic reward (e.g., praise) or an extrinsic reward (e.g., US 1 dollar). After a one-week delay, participants' retrieval performance for the word list was significantly better in the extrinsic reward groups, whether the reward was expected or not, than in controls. Those who received the intrinsic reward performed somewhat better than controls, but the difference was not significant. Thus, at least some forms of arousal and reward, even when semantically unrelated to the learned material, can effectively modulate memory consolidation. These types of treatments might be useful for the development of new memory intervention strategies.

Intrinsic and Extrinsic Origins of the Polar Kerr Effect in a Chiral p-WAVE Superconductor

Science.gov (United States)

Goryo, Jun

Recently, the measurement of the polar Kerr effect (PKE) in the quasi two-dimensional superconductor Sr2RuO4, which is motivated to observe the chirality of px + ipy-wave pairing, has been reported. We clarify that the PKE has intrinsic and extrinsic (disorder-induced) origins. The extrinsic contribution would be dominant in the PKE experiment.

The effect of extrinsic motivation on cycle time trial performance.

Science.gov (United States)

Hulleman, Michiel; De Koning, Jos J; Hettinga, Florentina J; Foster, Carl

2007-04-01

Athletes occasionally follow pacing patterns that seem unreasonably aggressive compared with those of prerace performances, potentially because of the motivation provided by competition. This study evaluated the effect of extrinsic motivation on cyclists' time trial performance. Well-trained recreational cyclists (N=7) completed four 1500-m laboratory time trials including a practice trial, two self-paced trials, and a trial where a monetary reward was offered. Time, total power output, power output attributable to aerobic and anaerobic metabolic sources, VO2, and HR were measured. The time required for the second, third, and last (extrinsically motivated) time trials was 133.1 +/- 2.1, 134.1 +/- 3.4, and 133.6 +/- 3.0 s, respectively, and was not different (P>0.05). There were no differences for total (396 +/- 19, 397 +/- 23, and 401 +/- 17 W), aerobic (253 +/- 12, 254 +/- 10, and 246 +/- 13 W), and anaerobic (143 +/- 14, 143 +/- 21, and 155 +/- 11 W) power output. The highest VO2 was not different over consecutive time trials (3.76 +/- 0.19, 3.73 +/- 0.16, and 3.71 +/- 0.22 L x min(-1)). When ranked by performance, without reference to the extrinsic motivation (131.9 +/- 2.4, 133.4 +/- 2.4, and 135.4 +/- 2.5 s), there was a significant difference for the first 100 m and from 100 to 300 m in power output, with a larger total power (560 +/- 102, 491 +/- 82, and 493 +/- 93; and 571 +/- 94, 513 +/- 41, and 484 +/- 88 W) and power attributable to anaerobic sources (446 +/- 100, 384 +/- 80, and 324 +/- 43; and 381 +/- 87, 383 +/- 90, and 289 +/- 91 W) for the fastest trial. Extrinsic motivation did not change the time trial performance, suggesting that 1500-m performance is extremely stable and not readily changeable with simple external motivation. The results suggest that spontaneous improvement in performance for time trials of this duration is attributable to greater early power output, which is primarily attributable to anaerobic metabolic sources.

Selective etching of injection molded zirconia-toughened alumina: Towards osseointegrated and antibacterial ceramic implants.

Science.gov (United States)

Flamant, Quentin; Caravaca, Carlos; Meille, Sylvain; Gremillard, Laurent; Chevalier, Jérôme; Biotteau-Deheuvels, Katia; Kuntz, Meinhard; Chandrawati, Rona; Herrmann, Inge K; Spicer, Christopher D; Stevens, Molly M; Anglada, Marc

2016-12-01

Due to their outstanding mechanical properties and excellent biocompatibility, zirconia-toughened alumina (ZTA) ceramics have become the gold standard in orthopedics for the fabrication of ceramic bearing components over the last decade. However, ZTA is bioinert, which hampers its implantation in direct contact with bone. Furthermore, periprosthetic joint infections are now the leading cause of failure for joint arthroplasty prostheses. To address both issues, an improved surface design is required: a controlled micro- and nano-roughness can promote osseointegration and limit bacterial adhesion whereas surface porosity allows loading and delivery of antibacterial compounds. In this work, we developed an integrated strategy aiming to provide both osseointegrative and antibacterial properties to ZTA surfaces. The micro-topography was controlled by injection molding. Meanwhile a novel process involving the selective dissolution of zirconia (selective etching) was used to produce nano-roughness and interconnected nanoporosity. Potential utilization of the porosity for loading and delivery of antibiotic molecules was demonstrated, and the impact of selective etching on mechanical properties and hydrothermal stability was shown to be limited. The combination of injection molding and selective etching thus appears promising for fabricating a new generation of ZTA components implantable in direct contact with bone. Zirconia-toughened alumina (ZTA) is the current gold standard for the fabrication of orthopedic ceramic components. In the present work, we propose an innovative strategy to provide both osseointegrative and antibacterial properties to ZTA surfaces: we demonstrate that injection molding allows a flexible design of surface micro-topography and can be combined with selective etching, a novel process that induces nano-roughness and surface interconnected porosity without the need for coating, avoiding reliability issues. These surface modifications have the

Toughening and healing of composites by CNTs reinforced copolymer nylon micro-particles

Science.gov (United States)

Kostopoulos, V.; Kotrotsos, A.; Tsokanas, P.; Tsantzalis, S.

2018-02-01

In this work, nylon micro-particles, both undoped and doped with multiwall carbon nanotubes played the role of the self-healing agent into carbon fibre/epoxy composites (CFRPs). These micro-particles were blended with epoxy matrix and the resulting mixture was used for the composites fabrication. Three types of composites were manufactured; the reference CFRP and the modified CFRPs with undoped and doped nylon micro-particles. After manufacturing, these composites were tested under mode I and II fracture loading conditions and it was shown that the interlaminar fracture toughness characteristics of both nylon modified composites were significantly increased. After first fracture, healing process was activated for the tested nylon modified samples and revealed high fracture toughness characteristics recovery. Morphology examinations supported the results and elucidated the involved toughening and failure mechanisms. Finally, the in-plane mechanical and thermo-mechanical properties of all the composites were characterized for identifying possible knock-down effects due to the nylon modification of composites.

Intrinsic motivation, extrinsic motivation, and learning English as a foreign language.

Science.gov (United States)

Shaikholeslami, Razieh; Khayyer, Mohammad

2006-12-01

The objective of this study was to examine the relationships of amotivation, extrinsic motivation, and intrinsic motivation with learning the English language. The 230 Iranian students at Shiraz University were tested using the Language Learning Orientations Scales to measure Amotivation, Extrinsic Motivation, and Intrinsic Motivation as explanatory variables. Grade point average in English exams was selected as a measure of English learning Achievement. Multiple regression analysis revealed that learning Achievement scores were predicted by scores on the Amotivation subscale, Introjected Regulation subscale, Knowledge subscale, and Stimulation subscale, whereas, the External and Identified Regulation and Accomplishment subscales did not have a significant relationship with Achievement. The results are discussed in terms of differences in Iranian context and culture.

Flavor Profile of Chinese Liquor Is Altered by Interactions of Intrinsic and Extrinsic Microbes.

Science.gov (United States)

Wu, Qun; Kong, Yu; Xu, Yan

2016-01-15

The flavor profile of Chinese liquor is the result of the metabolic activity of its microbial community. Given the importance of the microbial interaction, a novel way to control the liquor's flavor is by regulating the composition of the community. In this study, we efficiently improved the liquor's flavor by perturbing the intrinsic microbial metabolism with extrinsic microbes. We first constructed a basic microbial group (intrinsic) containing Saccharomyces cerevisiae, Wickerhamomyces anomalus, and Issatchenkia orientalis and added special flavor producers (extrinsic), Saccharomyces uvarum and Saccharomyces servazzii, to this intrinsic group. Upon the addition of the extrinsic microbes, the maximum specific growth rates of S. cerevisiae and I. orientalis increased from 6.19 to 43.28/day and from 1.15 to 14.32/day, respectively, but that of W. anomalus changed from 1.00 to 0.96/day. In addition, most volatile compounds known to be produced by the extrinsic strains were not produced. However, more esters, alcohols, and acids were produced by S. cerevisiae and I. orientalis. Six compounds were significantly different by random forest analysis after perturbation. Among them, increases in ethyl hexanoate, isobutanol, and 3-methylbutyric acid were correlated with S. cerevisiae and I. orientalis, and a decrease in geranyl acetone was correlated with W. anomalus. Variations in ethyl acetate and 2-phenylethanol might be due to the varied activity of W. anomalus and S. cerevisiae. This work showed the effect of the interaction between the intrinsic and extrinsic microbes on liquor flavor, which would be beneficial for improving the quality of Chinese liquor. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

An Analysis of Intrinsic and Extrinsic Hand Muscle EMG for Improved Pattern Recognition Control.

Science.gov (United States)

Adewuyi, Adenike A; Hargrove, Levi J; Kuiken, Todd A

2016-04-01

Pattern recognition control combined with surface electromyography (EMG) from the extrinsic hand muscles has shown great promise for control of multiple prosthetic functions for transradial amputees. There is, however, a need to adapt this control method when implemented for partial-hand amputees, who possess both a functional wrist and information-rich residual intrinsic hand muscles. We demonstrate that combining EMG data from both intrinsic and extrinsic hand muscles to classify hand grasps and finger motions allows up to 19 classes of hand grasps and individual finger motions to be decoded, with an accuracy of 96% for non-amputees and 85% for partial-hand amputees. We evaluated real-time pattern recognition control of three hand motions in seven different wrist positions. We found that a system trained with both intrinsic and extrinsic muscle EMG data, collected while statically and dynamically varying wrist position increased completion rates from 73% to 96% for partial-hand amputees and from 88% to 100% for non-amputees when compared to a system trained with only extrinsic muscle EMG data collected in a neutral wrist position. Our study shows that incorporating intrinsic muscle EMG data and wrist motion can significantly improve the robustness of pattern recognition control for application to partial-hand prosthetic control.

SiC Nanoparticles Toughened-SiC/MoSi2-SiC Multilayer Functionally Graded Oxidation Protective Coating for Carbon Materials at High Temperatures

Science.gov (United States)

Abdollahi, Alireza; Ehsani, Naser; Valefi, Zia; Khalifesoltani, Ali

2017-05-01

A SiC nanoparticle toughened-SiC/MoSi2-SiC functionally graded oxidation protective coating on graphite was prepared by reactive melt infiltration (RMI) at 1773 and 1873 K under argon atmosphere. The phase composition and anti-oxidation behavior of the coatings were investigated. The results show that the coating was composed of MoSi2, α-SiC and β-SiC. By the variations of Gibbs free energy (calculated by HSC Chemistry 6.0 software), it could be suggested that the SiC coating formed at low temperatures by solution-reprecipitation mechanism and at high temperatures by gas-phase reactions and solution-reprecipitation mechanisms simultaneously. SiC nanoparticles could improve the oxidation resistance of SiC/MoSi2-SiC multiphase coating. Addition of SiC nanoparticles increases toughness of the coating and prevents spreading of the oxygen diffusion channels in the coating during the oxidation test. The mass loss and oxidation rate of the SiC nanoparticle toughened-SiC/MoSi2-SiC-coated sample after 10-h oxidation at 1773 K were only 1.76% and 0.32 × 10-2 g/cm3/h, respectively.

Quantifying Intrinsic and Extrinsic Contributions to Human Longevity: Application of a Two-Process Vitality Model to the Human Mortality Database.

Science.gov (United States)

Sharrow, David J; Anderson, James J

2016-12-01

The rise in human life expectancy has involved declines in intrinsic and extrinsic mortality processes associated, respectively, with senescence and environmental challenges. To better understand the factors driving this rise, we apply a two-process vitality model to data from the Human Mortality Database. Model parameters yield intrinsic and extrinsic cumulative survival curves from which we derive intrinsic and extrinsic expected life spans (ELS). Intrinsic ELS, a measure of longevity acted on by intrinsic, physiological factors, changed slowly over two centuries and then entered a second phase of increasing longevity ostensibly brought on by improvements in old-age death reduction technologies and cumulative health behaviors throughout life. The model partitions the majority of the increase in life expectancy before 1950 to increasing extrinsic ELS driven by reductions in environmental, event-based health challenges in both childhood and adulthood. In the post-1950 era, the extrinsic ELS of females appears to be converging to the intrinsic ELS, whereas the extrinsic ELS of males is approximately 20 years lower than the intrinsic ELS.

Stochastic synchronization of neuronal populations with intrinsic and extrinsic noise.

KAUST Repository

Bressloff, Paul C; Lai, Yi Ming

2011-01-01

We extend the theory of noise-induced phase synchronization to the case of a neural master equation describing the stochastic dynamics of an ensemble of uncoupled neuronal population oscillators with intrinsic and extrinsic noise. The master

Intrinsic and extrinsic geometry of random surfaces

International Nuclear Information System (INIS)

Jonsson, T.

1992-01-01

We prove that the extrinsic Hausdorff dimension is always greater than or equal to the intrinsic Hausdorff dimension in models of triangulated random surfaces with action which is quadratic in the separation of vertices. We furthermore derive a few naive scaling relations which relate the intrinsic Hausdorff dimension to other critical exponents. These relations suggest that the intrinsic Hausdorff dimension is infinite if the susceptibility does not diverge at the critical point. (orig.)

The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

Directory of Open Access Journals (Sweden)

Chengedzai Mafini

2014-04-01

Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation. Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s public sector as evidenced by the high incidences of industrial action and labour turnover. This study contributes to this subject by identifying the extrinsic factors that could be optimised with a view to enhancing job and life satisfaction amongst government employees. Research approach, design and method: The study used the quantitative research survey approach: a questionnaire was administered to 246 employees in a South African public organisation. Extrinsic motivation factors were identified using principal components analysis. Mean score ranking was used to compare the relative importance of all factors. The conceptual framework was tested using Spearman’s rank correlation analysis and linear regression analysis. Main findings: Statistically significant relationships were observed between job satisfaction and four extrinsic motivation factors: remuneration, quality of work life, supervision and teamwork. The relationship with promotion was insignificant, but a statistically significant relationship was established with life satisfaction. Practical/managerial implications: The findings may be used to implement strategies for enhancing employee performance and industrial relations within public organisations. Contribution/value-add: The study provides evidence of the interplay between extrinsic motivation, job satisfaction and life satisfaction for public servants in developing countries.

The extrinsic influence of carbon fibre reinforced plastic laminates to ...

Indian Academy of Sciences (India)

The extrinsic influence of carbon fibre reinforced plastic laminates to strengthen steel structures ... The intrinsic advantages of strengthening the steel-based structures by the use of fibre reinforced plastic (FRP) material have ... Sadhana | News.

Endogenous Pain Modulation Induced by Extrinsic and Intrinsic Psychological Threat in Healthy Individuals.

Science.gov (United States)

Gibson, William; Moss, Penny; Cheng, Tak Ho; Garnier, Alexandre; Wright, Anthony; Wand, Benedict M

2018-03-01

Many factors interact to influence threat perception and the subsequent experience of pain. This study investigated the effect of observing pain (extrinsic threat) and intrinsic threat of pain to oneself on pressure pain threshold (PPT). Forty socially connected pairs of healthy volunteers were threat-primed and randomly allocated to experimental or control roles. An experimental pain modulation paradigm was applied, with non-nociceptive threat cues used as conditioning stimuli. In substudy 1, the extrinsic threat to the experimental participant was observation of the control partner in pain. The control participant underwent hand immersion in noxious and non-noxious water baths in randomized order. Change in the observing participant's PPT from baseline to mid- and postimmersion was calculated. A significant interaction was found for PPT between conditions and test time (F 2,78  = 24.9, P Extrinsic and intrinsic threat of pain, in the absence of any afferent input therefore influences pain modulation. This may need to be considered in studies that use noxious afferent input with populations who show dysfunctional pain modulation. The effect on endogenous analgesia of observing another's pain and of threat of pain to oneself was investigated. Extrinsic as well as intrinsic threat cues, in the absence of any afferent input, increased pain thresholds, suggesting that mere threat of pain may initiate analgesic effects in traditional noxious experimental paradigms. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

College Student Intrinsic and/or Extrinsic Motivation and Learning.

Science.gov (United States)

Lin, Yi-Guang; McKeachie, Wilbert J.

This paper investigates the joint effects of intrinsic and extrinsic goals on college students' learning in an introductory psychology course, a biology course, and several social science courses. The study questioned whether higher levels of motivation lead to better student performance. College students were surveyed using the Intrinsic Goal…

Critical dimension of strings with an extrinsic curvature

International Nuclear Information System (INIS)

Matsuki, T.; Viswanathan, K.S.

1988-01-01

The conformal anomaly is calculated by using the path-integral method to determine the critical dimension for a string theory with an extrinsic curvature by appropriately defining the first-order form of this Lagrangian. The critical dimension, defined by the vanishing of the Liouville kinetic term, is found to be D = 26, the same as for the ordinary bosonic string theory

The effect of extrinsic motivation on cycle time trial performance

NARCIS (Netherlands)

Hulleman, M.; de Koning, J.J.; Hettinga, F.J.; Foster, C.

2007-01-01

PURPOSE: Athletes occasionally follow pacing patterns that seem unreasonably aggressive compared with those of prerace performances, potentially because of the motivation provided by competition. This study evaluated the effect of extrinsic motivation on cyclists' time trial performance. METHODS:

Intrinsic and extrinsic drivers of succession: Effects of habitat age and season on an aquatic insect community.

Science.gov (United States)

Murrell, Ebony G; Ives, Anthony R; Juliano, Steven A

2014-06-01

1. Classical studies of succession, largely dominated by plant community studies, focus on intrinsic drivers of change in community composition, such as interspecific competition and changes to the abiotic environment. They often do not consider extrinsic drivers of colonization, such as seasonal phenology, that can affect community change. 2. We investigated both intrinsic and extrinsic drivers of succession for dipteran communities that occupy ephemeral pools, such as those in artificial containers. By initiating communities at different times in the season and following them over time, we compared the relative importance of intrinsic (i.e., habitat age) vs. extrinsic (i.e., seasonal phenology) drivers of succession. 3. We placed water-filled artificial containers in a deciduous forest with 20 containers initiated in each of three months. Containers were sampled weekly to assess community composition. Repeated-measures mixed-effects analysis of community correspondence analysis (CA) scores enabled us to partition intrinsic and extrinsic effects on succession. Covariates of temperature and precipitation were also tested. 4. Community trajectories (as defined by CA) differed significantly with habitat age and season, indicating that both intrinsic and extrinsic effects influence succession patterns. Comparisons of AICcs showed that habitat age was more important than season for species composition. Temperature and precipitation did not explain composition changes beyond those explained by habitat age and season. 5. Quantification of relative strengths of intrinsic and extrinsic effects on succession in dipteran and other ephemeral communities enables us to disentangle processes that must be understood for predicting changes in community composition.

The influence of extrinsic motivation on competition-based selection.

Science.gov (United States)

Sänger, Jessica; Wascher, Edmund

2011-10-10

The biased competition approach to visuo-spatial attention proposes that the selection of competing information is effected by the saliency of the stimulus as well as by an intention-based bias of attention towards behavioural goals. Wascher and Beste (2010) [32] showed that the detection of relevant information depends on its relative saliency compared to irrelevant conflicting stimuli. Furthermore the N1pc, N2pc and N2 of the EEG varied with the strength of the conflict. However, this system could also be modulated by rather global mechanisms like attentional effort. The present study investigates such modulations by testing the influence of extrinsic motivation on the selection of competing stimuli. Participants had to detect a luminance change in various conditions among others against an irrelevant orientation change. Half of the participants were motivated to maximize their performance by the announcement of a monetary reward for correct responses. Participants who were motivated had lower error rates than participants who were not motivated. The event-related lateralizations of the EEG showed no motivation-related effect on the N1pc, which reflects the initial saliency driven orientation of attention towards the more salient stimulus. The subsequent N2pc was enhanced in the motivation condition. Extrinsic motivation was also accompanied by enhanced fronto-central negativities. Thus, the data provide evidence that the improvement of selection performance when participants were extrinsically motivated by announcing a reward was not due to changes in the initial saliency based processing of information but was foremost mediated by improved higher-level mechanisms. Copyright © 2011 Elsevier B.V. All rights reserved.

Ekonomická analýza spojení cestovních agentur Obnova, s.r.o. a Cestovní agentura Marcela Drašnarová

OpenAIRE

Abrahamová, Jana

2009-01-01

The thesis looks at a detailed evaluation of the potential merger of two travel agents (Travel Agent Obnova Ltd., and Travel Agent Marcela Drašnarová). The first part deals with a comprehensive analysis of both companies. The theoretical characteristic of financial analysis builds its practical implementation on the example of Travel Agent Obnova. Qualitative analysis is based on PEST analysis, competitive analysis and SWOT analysis for the two above mentioned companies. The second part is de...

The influence of gamma radiation on the ESC behaviour of a toughened PMMA through stress relaxation

International Nuclear Information System (INIS)

Sousa, Alexandre R.; Araujo, Elmo S.; Rabello, Marcelo S.

2009-01-01

On this work we studied the ESC degradation behaviour of a toughened PMMA irradiated with different gamma radiation doses. Tensile samples were obtained by injection moulding, and then irradiated using a 60 Co source. The samples irradiated on several doses were submitted to relaxation tests under air, ethanol and ethylene glycol. The results showed that the ESC action was intensified with the rising radiation doses when the relaxation tests were done under ethanol. On the tests under ethylene glycol the ESC effect was observed only to the irradiated polymer through the higher dose and under the higher relaxation load. The fracture surface analysis of tested relaxation samples, under ethanol, showed a dendritic pattern formed on fracture surfaces. (author)

A validity generalization procedure to test relations between intrinsic and extrinsic motivation and influence tactics.

Science.gov (United States)

Barbuto, John E; Moss, Jennifer A

2006-08-01

The relations of intrinsic and extrinsic motivation with use of consultative, legitimating, and pressure influence tactics were examined using validity generalization procedures. 5 to 7 field studies with cumulative samples exceeding 800 were used to test each relationship. Significance was found for relation between agents' intrinsic motivation and their use of consultative influence tactics and agents' extrinsic motivation and their use of legitimating influence tactics.

Reanalysis of the EMC charm production data with extrinsic and intrinsic charm at NLO

International Nuclear Information System (INIS)

Harris, B.W.; Vogt, R.

1996-01-01

A calculation of the next-to-leading order exclusive extrinsic charm quark differential distributions in deeply inelastic electroproduction has recently been completed. Using these results we compare the NLO extrinsic contributions to the charm structure function F 2 (x,Q 2 ,m c 2 ) with the corresponding NLO intrinsic contributions. The results of this analysis are compared with the EMC DIS charm quark data and evidence for an intrinsic charm component in the proton is found. (orig.)

The Path Taken: Consequences of Attaining Intrinsic and Extrinsic Aspirations in Post-College Life.

Science.gov (United States)

Niemiec, Christopher P; Ryan, Richard M; Deci, Edward L

2009-06-01

Life goals, or aspirations, organize and direct behavior over extended periods of time. The present study, guided by self-determination theory, examined the consequences of pursuing and attaining aspirations over a one-year period in a post-college sample. Results indicated that placing importance on either intrinsic or extrinsic aspirations related positively to attainment of those goals. Yet, whereas attainment of intrinsic aspirations related positively to psychological health, attainment of extrinsic aspirations did not; indeed, attainment of extrinsic aspirations related positively to indicators of ill-being. Also as predicted, the association between change in attainment of intrinsic aspirations and change in psychological health was mediated by change in the satisfaction of the basic psychological needs for autonomy, competence, and relatedness. Discussion focuses on the idea that not all goal attainment is beneficial; rather, attainment of aspirations with different contents relates differentially to psychological health.

Giant Circular Dichroism in Individual Carbon Nanotubes Induced by Extrinsic Chirality

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A. Yokoyama

2014-01-01

Full Text Available Circular dichroism is widely used for characterizing organic and biological materials, but measurements at a single-molecule level are challenging because differences in absorption for opposite helicities are small. Here, we show that extrinsic chirality can induce giant circular dichroism in individual carbon nanotubes, with the degree of polarization reaching 65%. The signal has a large dependence on the incidence angle, consistent with extrinsic-chirality-induced effects in which symmetry is broken by the optical wave vector. We propose that the field-induced charge distribution on the substrate results in an efficient polarization conversion, giving rise to the giant dichroism. Our results highlight the possibility of polarization manipulation at the nanoscale for applications in integrated photonics and novel metamaterial designs.

The Effects of Extrinsic Rewards on Admissions Counselors' Performance

Science.gov (United States)

Gardner-Engel, Miriam

2010-01-01

This study examines the best ways to motivate college admissions counselors. A review of literature revealed multiple perspectives on intrinsic and extrinsic as well as tangible and intangible rewards. Primary research was designed to examine the impact of tangible rewards and verbal reinforcements with a convenience sample of nine college…

Bioavailability of zinc from defatted soy flour, soy hulls and whole eggs as determined by intrinsic and extrinsic labeling techniques.

Science.gov (United States)

Meyer, N R; Stuart, M A; Weaver, C M

1983-06-01

Bioavailability of zinc from diets prepared from intrinsically and extrinsically labeled autoclaved, defatted soy flour and scrambled, freeze-dried egg was investigated in male rats marginally depleted in zinc. In one study, retention of zinc from intrinsically labeled soybean flour (73%) was significantly less than from 65ZnCl2 extrinsically added to a soy flour-based diet (80%). Zinc from intrinsically labeled soybean hulls and from soy flour diets containing 10% soybean hulls extrinsically labeled with 65ZnCl2 was as available as the zinc from the extrinsically labeled soy flour diet. In a second study, extrinsic and intrinsic labeling techniques gave a similar assessment of bioavailability of zinc from egg- and soy flour-based diets when extrinsic labeling was accomplished by thoroughly mixing 65ZnCl2 with the protein source prior to incorporation into the diet. Absorption of 65Zn was greater from egg diets than from soy flour diets and of intermediate value from mixed soy flour and egg (50:50, wt/wt) diets regardless of which protein source was labeled, indicating that the zinc entered a common pool.

Intrinsic and Extrinsic School Motivation as a Function of Age: The Mediating Role of Autonomy Support

Science.gov (United States)

Gillet, Nicolas; Vallerand, Robert J.; Lafreniere, Marc-Andre K.

2012-01-01

The main purpose of the present research was to investigate school intrinsic and extrinsic motivation, and amotivation as a function of age in a sample of 1,600 elementary and high school students aged 9-17 years. First, results revealed a systematic decrease in intrinsic motivation and self-determined extrinsic motivation from age 9 to 12 years,…

Generalized isoperimetric inequalities for extrinsic balls in minimal submanifolds

DEFF Research Database (Denmark)

Markvorsen, Steen; Palmer, Vicente

2002-01-01

The volume of an extrinsic ball in a minimal submanifold has a well defined lower bound when the ambient manifold has an upper bound on its sectional curvatures, see e.g. [2] and [10]. When this upper bound is non-positive, the second named author has shown an isoperimetric inequality for such do...

A comparison of South African and German extrinsic and intrinsic motivation

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Robin Snelgar

2017-04-01

Aim: The main objective of this study was to investigate similarities and differences concerning extrinsic and intrinsic motivation in the workplace between German and South African cultures by examining individuals with working experience and tertiary education specifically. In addition, the research investigated differences in the motivation of respondents with regard to demographics such as gender, age and income. Setting: The setting took place in South Africa and Germany. Methods: In the study, exploratory factor analysis was utilised to prove validity of Cinar, Bektas and Aslan’s two-dimensional measure of extrinsic and intrinsic motivation. Moreover, analysis of variance and t-tests were used to show differences among demographic variables. Descriptive statistics such as means, central tendency and Cronbach’s alpha were also utilised. Results: The results revealed preferences for intrinsic motivational factors for the whole sample with higher levels of intrinsic motivation for the South African respondents compared to German respondents. Demographic characteristics played a minor role in determining levels of intrinsic motivation within individuals. Culture, however, played the biggest role in determining one’s levels of intrinsic or extrinsic motivation. Conclusion: These findings play an important role in explaining differences in motivation between the two countries Germany and South Africa. It highlights the important role that cultural differences play in shaping one’s form of motivation.

Coordination of intrinsic and extrinsic hand muscle activity as a function of wrist joint angle during two-digit grasping.

Science.gov (United States)

Johnston, Jamie A; Bobich, Lisa R; Santello, Marco

2010-04-26

Fingertip forces result from the activation of muscles that cross the wrist and muscles whose origins and insertions reside within the hand (extrinsic and intrinsic hand muscles, respectively). Thus, tasks that involve changes in wrist angle affect the moment arm and length, hence the force-producing capabilities, of extrinsic muscles only. If a grasping task requires the exertion of constant fingertip forces, the Central Nervous System (CNS) may respond to changes in wrist angle by modulating the neural drive to extrinsic or intrinsic muscles only or by co-activating both sets of muscles. To distinguish between these scenarios, we recorded electromyographic (EMG) activity of intrinsic and extrinsic muscles of the thumb and index finger as a function of wrist angle during a two-digit object hold task. We hypothesized that changes in wrist angle would elicit EMG amplitude modulation of the extrinsic and intrinsic hand muscles. In one experimental condition we asked subjects to exert the same digit forces at each wrist angle, whereas in a second condition subjects could choose digit forces for holding the object. EMG activity was significantly modulated in both extrinsic and intrinsic muscles as a function of wrist angle (both pextrinsic and intrinsic muscles as a muscle synergy. These findings are discussed within the theoretical frameworks of synergies and common neural input across motor nuclei of hand muscles. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Effects of empathic paraphrasing - Extrinsic emotion regulation in social conflict

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Maria eSeehausen

2012-11-01

Full Text Available In the present study, we investigated the effects of empathic paraphrasing as an extrinsic emotion regulation technique in social conflict. We hypothesized that negative emotions elicited by social conflict can be regulated extrinsically in a conversation by a listener following the narrator’s perspective and verbally expressing cognitive empathy.20 participants were interviewed on an ongoing or recently self-experienced social conflict. The interviewer utilized ten standardized open questions inviting participants to describe their perception of the conflict. After each of the ten descriptions, the interviewer responded by either paraphrasing or taking notes (control condition. Valence ratings pertaining to the current emotional state were assessed during the interview along with psychophysiological and voice recordings.Participants reported feeling less negative after hearing the interviewer paraphrase what they had said. In addition, we found a lower sound intensity of participants' voices when answering to questions following a paraphrase. At the physiological level, skin conductance response, as well as heart rate, was higher during paraphrasing than during taking notes, while blood volume pulse amplitude was lower during paraphrasing, indicating higher autonomic arousal.The results show that demonstrating cognitive empathy through paraphrasing can extrinsically regulate negative emotion on a short-term basis. Paraphrasing led to enhanced autonomic activation in recipients, while at the same time influencing emotional valence in the direction of feeling better. A possible explanation for these results is that being treated in an empathic manner may stimulate a more intense emotion processing helping to transform and resolve the conflict.

Intrinsic atopic dermatitis shows similar TH2 and higher TH17 immune activation compared with extrinsic atopic dermatitis.

Science.gov (United States)

Suárez-Fariñas, Mayte; Dhingra, Nikhil; Gittler, Julia; Shemer, Avner; Cardinale, Irma; de Guzman Strong, Cristina; Krueger, James G; Guttman-Yassky, Emma

2013-08-01

Atopic dermatitis (AD) is classified as extrinsic and intrinsic, representing approximately 80% and 20% of patients with the disease, respectively. Although sharing a similar clinical phenotype, only extrinsic AD is characterized by high serum IgE levels. Because most patients with AD exhibit high IgE levels, an "allergic"/IgE-mediated disease pathogenesis was hypothesized. However, current models associate AD with T-cell activation, particularly TH2/TH22 polarization, and epidermal barrier defects. We sought to define whether both variants share a common pathogenesis. We stratified 51 patients with severe AD into extrinsic AD (n = 42) and intrinsic AD (n = 9) groups (with similar mean disease activity/SCORAD scores) and analyzed the molecular and cellular skin pathology of lesional and nonlesional intrinsic AD and extrinsic AD by using gene expression (real-time PCR) and immunohistochemistry. A significant correlation between IgE levels and SCORAD scores (r = 0.76, P extrinsic AD. Marked infiltrates of T cells and dendritic cells and corresponding epidermal alterations (keratin 16, Mki67, and S100A7/A8/A9) defined lesional skin of patients with both variants. However, higher activation of all inflammatory axes (including TH2) was detected in patients with intrinsic AD, particularly TH17 and TH22 cytokines. Positive correlations between TH17-related molecules and SCORAD scores were only found in patients with intrinsic AD, whereas only patients with extrinsic AD showed positive correlations between SCORAD scores and TH2 cytokine (IL-4 and IL-5) levels and negative correlations with differentiation products (loricrin and periplakin). Although differences in TH17 and TH22 activation exist between patients with intrinsic AD and those with extrinsic AD, we identified common disease-defining features of T-cell activation, production of polarized cytokines, and keratinocyte responses to immune products. Our data indicate that a TH2 bias is not the sole cause of high Ig

Extrinsic Reinforcement in the Classroom: Bribery or Best Practice

Science.gov (United States)

Akin-Little, K. Angeleque; Eckert, Tanya L.; Lovett, Benjamin J.; Little, Steven G.

2004-01-01

The debate over the effects of the use of extrinsic reinforcement in classrooms, businesses, and societal settings has been occurring for over 30 years. Some theorists have cautioned against the use of reward, whereas others have found little, if any, detrimental effect. This article examines the debate with an emphasis on data-based findings. The…

Examining extrinsic factors that influence product acceptance: a review.

Science.gov (United States)

Li, X E; Jervis, S M; Drake, M A

2015-05-01

Drivers of liking (DOL) studies are useful for product development to formulate acceptable products; however, DOL alone are insufficient for understanding why a product is purchased and repurchased, which is ultimately the indication of a successful product. Ultimately sensory attributes drive product success (that is, repeat and continued purchase). However, ignoring the importance of extrinsic factors may neglect the vital product attributes responsible for the initial purchase, which may in turn, affect repeat purchase. The perception of sensory attributes assessed by DOL is mitigated by external perceptions of quality. If the sensory attributes do not deliver based upon the quality cues, the product will not be acceptable. Four key extrinsic factors that affect DOL are the perceived satiety, brand and labeling, price, and the emotional impact to decision making. In order to more thoroughly understand what the DOL for a product is, these 4 product cues should be considered in conjunction with sensory attribute perception to gain a holistic understanding of product acceptance. © 2015 Institute of Food Technologists®

Fatigue Performance and Multiscale Mechanisms of Concrete Toughened by Polymers and Waste Rubber

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Bo Chen

2014-01-01

Full Text Available For improving bending toughness and fatigue performance of brittle cement-based composites, two types of water-soluble polymers (such as dispersible latex powder and polyvinyl alcohol powder and waste tire-rubber powders are added to concrete as admixtures. Multiscale toughening mechanisms of these additions in concretes were comprehensively investigated. Four-point bending fatigue performance of four series concretes is conducted under a stress level of 0.70. The results show that the effects of dispersible latex powder on bending toughness and fatigue life of concrete are better than those of polyvinyl alcohol powder. Furthermore, the bending fatigue lives of concrete simultaneously containing polymers and waste rubber powders are larger than those of concrete with only one type of admixtures. The multiscale physics-chemical mechanisms show that high bonding effect and high elastic modulus of polymer films as well as good elastic property and crack-resistance of waste tire-rubber powders are beneficial for improving bending toughness and fatigue life of cementitious composites.

Studies of LENRA-Toughened PVC non-woven membranes prepared by electro spinning technique

International Nuclear Information System (INIS)

Dahlan Mohd; Mahathir Mohamed; Khirul Hafiz mohd Yusof

2010-01-01

Lately research in use of so-called green chemicals draws strong interest from research community due to the climate change issues. Malaysia is in strong position to take this advantage because we are among the world biggest producers of natural rubber and palm oil - the two sources of important green renewable chemical feedstock in the near future. For the last couple of years we have shown how modified natural rubbers especially liquid natural rubber and its derivatives such as liquid epoxidized natural rubber acrylate (LENRA) could be used in various applications via among others sol-gel technique and radiation curing technology. This time around we will show another application on how non-woven membranes made from PVC can be prepared by electro spinning technique using radiation curable LENRA as toughener. The electro spinning technique has great potential in producing nano fiber materials to be used in various applications to ensure sustainable energy and environments for the future. (author)

Teacher Rewards: Going beyond the Stickers--Moving beyond Extrinsic Motivation

Science.gov (United States)

Taylor, Cheryl; McNaney-Funk, Claire; Jardine, Don; Lehman, Geannette; Fok-Chan, Evelyn

2014-01-01

Studies have shown that teachers appreciate intrinsic rewards, such as student achievement, positive relationships with students, self-growth, and mastery of professional skills, far greater than extrinsic motivators, like holidays and salary (Plihal, 1981; Plihal, 1982; Ashiedu & Scott-Ladd, 2012; Baleghizadeh & Gordani, 2012). This paper…

Extrinsic Tooth Enamel Color Changes and Their Relationship with the Quality of Water Consumed

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Maria da Luz Rosário de Sousa

2012-10-01

Full Text Available The quality of the consumed drinking water may affect oral health. For example, the presence of iron in drinking water can cause aesthetic problems related to changes in dental enamel color. This study assessed the prevalence of extrinsic enamel color changes and their relationship with the quality of the water in the town of Caapiranga/AM-Brazil. Three hundred and forty six residents of the urban area were examined, and they also answered a questionnaire on eating habits and self-perceived oral health. As the initial results indicated an insufficient number of observations for the application of variance analysis (one-way ANOVA, the Student t test was chosen to compare levels of iron content in the water coming from two sources. The change in tooth color had a prevalence of 5.78% (20 people. The majority of the population (n = 261, 75.43% consumed well water. Those who presented extrinsic stains were uncomfortable with the appearance of their teeth (15.09%. We conclude that while there is excess of iron in the water in this region of Brazil, no association between extrinsic stains on the enamel and the level of iron in the water was found. There was a low prevalence of extrinsic stains in Caaparinga, being found only in children and adolescents. In the present study, an association between the presence of stains and the consumption of açai was determined, and those who presented them felt uncomfortable about their aesthetics.

Common input to motor units of intrinsic and extrinsic hand muscles during two-digit object hold.

Science.gov (United States)

Winges, Sara A; Kornatz, Kurt W; Santello, Marco

2008-03-01

Anatomical and physiological evidence suggests that common input to motor neurons of hand muscles is an important neural mechanism for hand control. To gain insight into the synaptic input underlying the coordination of hand muscles, significant effort has been devoted to describing the distribution of common input across motor units of extrinsic muscles. Much less is known, however, about the distribution of common input to motor units belonging to different intrinsic muscles and to intrinsic-extrinsic muscle pairs. To address this void in the literature, we quantified the incidence and strength of near-simultaneous discharges of motor units residing in either the same or different intrinsic hand muscles (m. first dorsal, FDI, and m. first palmar interosseus, FPI) during two-digit object hold. To extend the characterization of common input to pairs of extrinsic muscles (previous work) and pairs of intrinsic muscles (present work), we also recorded electromyographic (EMG) activity from an extrinsic thumb muscle (m. flexor pollicis longus, FPL). Motor-unit synchrony across FDI and FPI was weak (common input strength, CIS, mean +/- SE: 0.17 +/- 0.02). Similarly, motor units from extrinsic-intrinsic muscle pairs were characterized by weak synchrony (FPL-FDI: 0.25 +/- 0.02; FPL-FPI: 0.29 +/- 0.03) although stronger than FDI-FPI. Last, CIS from within FDI and FPI was more than three times stronger (0.70 +/- 0.06 and 0.66 +/- 0.06, respectively) than across these muscles. We discuss present and previous findings within the framework of muscle-pair specific distribution of common input to hand muscles based on their functional role in grasping.

The relationship between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation

OpenAIRE

Mafini, Chengedzai; Dlodlo, Nobukhosi

2014-01-01

Orientation: There is much research on extrinsic motivation, job satisfaction and life satisfaction in organisations. However, empirical evidence on how such factors affect employees in public organisations in developing countries is lacking. Research purpose: To examine the relationships between extrinsic motivation, job satisfaction and life satisfaction amongst employees in a public organisation. Motivation for the study: Labour strife is an endemic phenomenon in South Africa’s publ...

Alberta Consumers' Valuation of Extrinsic and Intrinsic Red Meat Attributes

DEFF Research Database (Denmark)

Steiner, Bodo; Gao, Fei; Unterschultz, Jim

2010-01-01

This paper analyzes Alberta consumers’ perceptions toward extrinsic and intrinsic attributes of bison and beef steaks. In contrast to published Canadian consumer studies on bison meat that were undertaken prior to May 2003, before the first BSE case of Canadian origin was identified in beef cattle...

Extrinsic Rewards and Intrinsic Motivation in Education: Reconsidered Once Again.

Science.gov (United States)

Deci, Edward L.; Koestner, Richard; Ryan, Richard M.

2001-01-01

Reviews the results of a meta analysis (E. Deci, R. Koestner, and R. Ryan, 1999) that shows that tangible extrinsic rewards do have a substantial undermining effect on intrinsic motivation. Discusses results, which support cognitive evaluation theory, in terms of their relevance for educational practice. (SLD)

Intrinsic and extrinsic neuromodulation of motor circuits.

Science.gov (United States)

Katz, P S

1995-12-01

Neuromodulation of motor circuits by extrinsic inputs provides enormous flexibility in the production of behavior. Recent work has shown that neurons intrinsic to central pattern-generating circuits can evoke neuromodulatory effects in addition to their neurotransmitting actions. Modulatory neurons often elicit a multitude of different effects attributable to actions at different receptors and/or through the release of co-transmitters. Differences in neuromodulation between species can account for differences in behavior. Modulation of neuromodulation may provide an additional level of flexibility to motor circuits.

Characterization of major histocompatibility complex (MHC DRB exon 2 and DRA exon 3 fragments in a primary terrestrial rabies vector (Procyon lotor.

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Sarrah Castillo

Full Text Available The major histocompatibility complex (MHC presents a unique system to explore links between genetic diversity and pathogens, as diversity within MHC is maintained in part by pathogen driven selection. While the majority of wildlife MHC studies have investigated species that are of conservation concern, here we characterize MHC variation in a common and broadly distributed species, the North American raccoon (Procyon lotor. Raccoons host an array of broadly distributed wildlife diseases (e.g., canine distemper, parvovirus and raccoon rabies virus and present important human health risks as they persist in high densities and in close proximity to humans and livestock. To further explore how genetic variation influences the spread and maintenance of disease in raccoons we characterized a fragment of MHC class II DRA exon 3 (250 bp and DRB exon 2 (228 bp. MHC DRA was found to be functionally monomorphic in the 32 individuals screened; whereas DRB exon 2 revealed 66 unique alleles among the 246 individuals screened. Between two and four alleles were observed in each individual suggesting we were amplifying a duplicated DRB locus. Nucleotide differences between DRB alleles ranged from 1 to 36 bp (0.4-15.8% divergence and translated into 1 to 21 (1.3-27.6% divergence amino acid differences. We detected a significant excess of nonsynonymous substitutions at the peptide binding region (P = 0.005, indicating that DRB exon 2 in raccoons has been influenced by positive selection. These data will form the basis of continued analyses into the spatial and temporal relationship of the raccoon rabies virus and the immunogenetic response in its primary host.

Intrinsic vs. extrinsic influences on life history expression: metabolism and parentally induced temperature influences on embryo development rate

Science.gov (United States)

Martin, Thomas E.; Ton, Riccardo; Nikilson, Alina

2013-01-01

Intrinsic processes are assumed to underlie life history expression and trade-offs, but extrinsic inputs are theorised to shift trait expression and mask trade-offs within species. Here, we explore application of this theory across species. We do this based on parentally induced embryo temperature as an extrinsic input, and mass-specific embryo metabolism as an intrinsic process, underlying embryonic development rate. We found that embryonic metabolism followed intrinsic allometry rules among 49 songbird species from temperate and tropical sites. Extrinsic inputs via parentally induced temperatures explained the majority of variation in development rates and masked a relationship with metabolism; metabolism explained a minor proportion of the variation in development rates among species, and only after accounting for temperature effects. We discuss evidence that temperature further obscures the expected interspecific trade-off between development rate and offspring quality. These results demonstrate the importance of considering extrinsic inputs to trait expression and trade-offs across species.

Analyzing the microfoundations of human violence in the DRC - intrinsic and extrinsic rewards and the prediction of appetitive aggression.

Science.gov (United States)

Haer, Roos; Banholzer, Lilli; Elbert, Thomas; Weierstall, Roland

2013-05-17

Civil wars are characterized by intense forms of violence, such as torture, maiming and rape. Political scientists suggest that this form of political violence is fostered through the provision of particular intrinsic and extrinsic rewards to combatants. In the field of psychology, the perpetration of this kind of cruelty is observed to be positively linked to appetitive aggression. Over time, combatants start to enjoy the fights and even the perpetration of atrocities. In this study, we examine how receiving rewards (intrinsic versus extrinsic) influence the level of appetitive aggression exhibited by former combatants. We surveyed 95 former combatants in the eastern provinces of the Democratic Republic of the Congo. Linear regression analyses reveal that intrinsic as well as extrinsic rewards are linked to the former combatants' Appetitive Aggression score. However, this relationship is partly determined by the way in which combatants are recruited: While abducted combatants seem to react more strongly to extrinsic rewards, the score of those that joined voluntarily is primarily determined by intrinsic rewards. We conclude that receiving rewards influence the level of appetitive aggression. However, which type of rewards (intrinsic versus extrinsic) is of most importance is determined by the way combatants are recruited.

Regulation of Intrinsic and Extrinsic Apoptotic Pathways in Osteosarcoma Cells Following Oleandrin Treatment.

Science.gov (United States)

Ma, Yunlong; Zhu, Bin; Yong, Lei; Song, Chunyu; Liu, Xiao; Yu, Huilei; Wang, Peng; Liu, Zhongjun; Liu, Xiaoguang

2016-11-23

Our previous study has reported the anti-tumor effect of oleandrin on osteosarcoma (OS) cells. In the current study, we mainly explored its potential regulation on intrinsic and extrinsic apoptotic pathway in OS cells. Cells apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected using fluorescence staining and flow cytometry. Caspase-3 activity was detected using a commercial kit. The levels of cytoplasmic cytochrome c, mitochondrial cytochrome c, bcl-2, bax, caspase-9, Fas, FasL, caspase-8 and caspase-3 were detected by Western blotting. z-VAD-fmk was applied to block both intrinsic and extrinsic apoptosis pathways, and cells apoptosis was also tested. Furthermore, we used z-LEHD-fmk and Fas blocking antibody to inhibit intrinsic and extrinsic pathways, separately, and the selectivity of oleandrin on these pathways was explored. Results showed that oleandrin induced the apoptosis of OS cells, which was accompanied by an increase in ROS and a decrease in MMP. Furthermore, cytochrome c level was reduced in mitochondria but elevated in the cytoplasm. Caspase-3 activity was enhanced by oleandrin in a concentration- and time-dependent manner. Oleandrin also down-regulated the expression of bcl-2, but up-regulated bax, caspase-9, Fas, FasL, caspase-8 and caspase-3. In addition, the suppression of both apoptotic pathways by z-VAD-fmk greatly reverted the oleandrin-induced apoptosis. Moreover, the suppression of one pathway by a corresponding inhibitor did not affect the regulation of oleandrin on another pathway. Taken together, we concluded that oleandrin induced apoptosis of OS cells via activating both intrinsic and extrinsic apoptotic pathways.

Toughening of carbon fibre reinforced polymer composites with rubber nanoparticles for advanced industrial applications

Directory of Open Access Journals (Sweden)

N. G. Ozdemir

2016-05-01

Full Text Available This study investigates the effects of nano carboxylic acrylonitrile butadiene rubber (CNBR-NP and nano acrylonitrile butadiene rubber (NBR-NP on the interlaminar shear strength and fracture toughness of carbon fibre reinforced polymer composites (CFRP with dicyandiamide-cured epoxy matrix. The results show that nano-size dispersion of rubber significantly improved the Mode I delamination fracture toughness (GIC of the CFRP by 250% and its Mode II delamination fracture toughness (GIIC by 80% with the addition of 20 phr of CNBR-NP. For the NBR-NP system, the GIC and GIIC delamination fracture toughness of the CFRP were increased by 200 and 80% respectively with the addition of 20 phr (parts per hundred rubber of nano rubber to the matrix. Scanning electron microscopy (SEM images of the fracture surface revealed that the toughening was mainly achieved by debonding of the nano rubber, crack path deflection and fibre bridging.

Dual tuning in creative processes: Joint contributions of intrinsic and extrinsic motivational orientations.

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Gong, Yaping; Wu, Junfeng; Song, Lynda Jiwen; Zhang, Zhen

2017-05-01

Intrinsic and extrinsic motivational orientations often coexist and can serve important functions. We develop and test a model in which intrinsic and extrinsic motivational orientations interact positively to influence personal creativity goal. Personal creativity goal, in turn, has a positive relationship with incremental creativity and an inverted U-shaped relationship with radical creativity. In a pilot study, we validated the personal creativity goal measure using 180 (Sample 1) and 69 (Sample 2) employees from a consulting firm. In the primary study, we tested the overall model using a sample of 657 research and development employees and their direct supervisors from an automobile firm. The results support the hypothesized model and yield several new insights. Intrinsic and extrinsic motivational orientations synergize with each other to strengthen personal creativity goal. Personal creativity goal in turn benefits incremental and radical creativity, but only up to a certain point for the latter. In addition to its linear indirect relationship with incremental creativity, intrinsic motivational orientation has an inverted U-shaped indirect relationship with radical creativity via personal creativity goal. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Magnetic order in graphite: Experimental evidence, intrinsic and extrinsic difficulties

International Nuclear Information System (INIS)

Esquinazi, P.; Barzola-Quiquia, J.; Spemann, D.; Rothermel, M.; Ohldag, H.; Garcia, N.; Setzer, A.; Butz, T.

2010-01-01

We discuss recently obtained data using different experimental methods including magnetoresistance measurements that indicate the existence of metal-free high-temperature magnetic order in graphite. Intrinsic as well as extrinsic difficulties to trigger magnetic order by irradiation of graphite are discussed in view of recently published theoretical work.

Extrinsic ureteropelvic junction obstruction from a crossing renal vessel: demography and imaging

Energy Technology Data Exchange (ETDEWEB)

Rooks, V.J.; Lebowitz, R.L. [Children' s Hospital and Harvard Medical School, Dept. of Radiology, Boston, MA (United States)

2001-02-01

Background. The increase in the use of prenatal ultrasound has revolutionized the detection of hydronephrosis and has had an unanticipated consequence. Objective. To describe the new demographics of symptomatic ureteropelvic junction (UPJ) obstruction and the characteristic imaging findings, when the obstruction is extrinsic, from a crossing renal vessel. Materials and methods. From a uroradiology database (1994 through 1999) we identified children with surgically corrected UPJ obstruction from intrinsic and extrinsic causes. Results. One hundred children had symptomatic UPJ obstruction treated by surgery. In 51 (49 %), obstruction was due to a crossing vessel. One hundred and one had UPJ obstruction detected by prenatal sonography. Only 11 (11 %) were due to a vessel. Two clinical and imaging findings were strongly suggestive of obstruction from a vessel: (1) in 5 of the 100 children the symptoms (pain, nausea, and vomiting) were intermittent. Only when symptoms were present were there hydronephrosis and obstruction; (2) in 51 of the 100 children a short segment of ureter, just below the UPJ, was filled with contrast or urine (on renal sonography, intravenous urography, or retrograde/antegrade ureterography). Conclusions. Extrinsic UPJ obstruction caused by a vessel is an uncommon cause of obstruction when all patients are considered. However, in symptomatic older patients whose hydronephrosis was not first identified on prenatal sonography, a vessel was the cause of obstruction in one-half. (orig.)

Intrinsic and Extrinsic Science: A Dialectic of Scientific Fame.

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Feist, Gregory J

2016-11-01

In this article, I argue that scientific fame and impact exists on a continuum from the mundane to the transformative/revolutionary. Ideally, one achieves fame and impact in science by synthesizing two extreme career prototypes: intrinsic and extrinsic research. The former is guided by interest, curiosity, passion, gut, and intuition for important untapped topics. The latter is guided by money, grants, and/or what is being published in top-tier journals. Assessment of fame and impact in science ultimately rests on productivity (publication) and some variation of its impact (citations). In addition to those traditional measures of impact, there are some relatively new metrics (e.g., the h index and altmetrics). If psychology is to achieve consensual cumulative progress and better rates of replication, I propose that upcoming psychologists would do well to understand that success is not equal to fame and that individual career success is not necessarily the same as disciplinary success. Finally, if one is to have a successful and perhaps even famous career in psychological science, a good strategy would be to synthesize intrinsic and extrinsic motives for one's research. © The Author(s) 2016.

Extrinsic coefficient charcterisation of PZT ceramics near the morphotropic phase boundary

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Albareda, A.

2006-06-01

Full Text Available PZT ceramics with high piezoelectric coefficients have high extrinsic contributions. This extrinsic behaviour, which is related to the domain wall movement, produces high non-linear effects that are sometimes inconvenient, for example when it increases the losses in power devices. The relation between extrinsic behaviour and non-linearities could be used to provide a good extrinsic characterization of materials in order to optimise the piezoelectric devices. In all cases the physical explanation of the behaviour is sought. The aim of this work is to study the dependence of the linear and non-linear dielectric, piezoelectric and mechanical coefficients on the Ti fraction in PZT ceramic compositions near the morphotropic phase boundary (MPB. The dependence of these coefficients on the defect concentration is also analysed. Hard ceramics belonging to Ferroperm Piezoceramics, with two different acceptor dopant levels, high and low, have been measured.

Las cerámicas PZT con coeficientes piezoeléctricos elevados poseen contribuciones extrínsecas grandes. Este comportamiento extrínseco, relacionado con el movimiento de las paredes de los dominios, comporta efectos no lineales grandes que no siempre son deseables, por ejemplo, al incrementar las pérdidas de los dispositivos piezoeléctricos. Esta correspondencia entre efectos extrínsecos y no linealidades puede ser utilizada para caracterizar las cerámicas con el fin de optimizar sus propiedades piezoeléctricas. En todos los casos se busca una interpretación física de los resultados obtenidos. El objetivo de este trabajo es el estudio de la dependencia de los coeficientes lineales y no lineales dieléctricos, piezoeléctricos y elásticos con la fracción de Ti en cerámicas PZT con composiciones de Zr-Ti cerca de la transición de fase morfotrópica (MPB. También se analiza la dependencia de estos coeficientes con la concentración de impurezas, utilizando para ello cerámicas de

Analyzing the microfoundations of human violence in the DRC - intrinsic and extrinsic rewards and the prediction of appetitive aggression

Science.gov (United States)

2013-01-01

Background Civil wars are characterized by intense forms of violence, such as torture, maiming and rape. Political scientists suggest that this form of political violence is fostered through the provision of particular intrinsic and extrinsic rewards to combatants. In the field of psychology, the perpetration of this kind of cruelty is observed to be positively linked to appetitive aggression. Over time, combatants start to enjoy the fights and even the perpetration of atrocities. In this study, we examine how receiving rewards (intrinsic versus extrinsic) influence the level of appetitive aggression exhibited by former combatants. Method We surveyed 95 former combatants in the eastern provinces of the Democratic Republic of the Congo. Results Linear regression analyses reveal that intrinsic as well as extrinsic rewards are linked to the former combatants’ Appetitive Aggression score. However, this relationship is partly determined by the way in which combatants are recruited: While abducted combatants seem to react more strongly to extrinsic rewards, the score of those that joined voluntarily is primarily determined by intrinsic rewards. Conclusions We conclude that receiving rewards influence the level of appetitive aggression. However, which type of rewards (intrinsic versus extrinsic) is of most importance is determined by the way combatants are recruited. PMID:23683122

Effects of extrinsic mortality on the evolution of aging: a stochastic modeling approach.

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Maxim Nikolaievich Shokhirev

Full Text Available The evolutionary theories of aging are useful for gaining insights into the complex mechanisms underlying senescence. Classical theories argue that high levels of extrinsic mortality should select for the evolution of shorter lifespans and earlier peak fertility. Non-classical theories, in contrast, posit that an increase in extrinsic mortality could select for the evolution of longer lifespans. Although numerous studies support the classical paradigm, recent data challenge classical predictions, finding that high extrinsic mortality can select for the evolution of longer lifespans. To further elucidate the role of extrinsic mortality in the evolution of aging, we implemented a stochastic, agent-based, computational model. We used a simulated annealing optimization approach to predict which model parameters predispose populations to evolve longer or shorter lifespans in response to increased levels of predation. We report that longer lifespans evolved in the presence of rising predation if the cost of mating is relatively high and if energy is available in excess. Conversely, we found that dramatically shorter lifespans evolved when mating costs were relatively low and food was relatively scarce. We also analyzed the effects of increased predation on various parameters related to density dependence and energy allocation. Longer and shorter lifespans were accompanied by increased and decreased investments of energy into somatic maintenance, respectively. Similarly, earlier and later maturation ages were accompanied by increased and decreased energetic investments into early fecundity, respectively. Higher predation significantly decreased the total population size, enlarged the shared resource pool, and redistributed energy reserves for mature individuals. These results both corroborate and refine classical predictions, demonstrating a population-level trade-off between longevity and fecundity and identifying conditions that produce both

Extrinsic motivation and job satisfaction of teachers' in public post ...

African Journals Online (AJOL)

This study was aimed at evaluating the relationship between extrinsic motivation and the job satisfaction of teachers' in public post primary schools in Cross River State, Nigeria. A sample of 125 teachers' was randomly drawn for the study. A four point likert-type questionnaire was used to gather data which was analyzed ...

Binary Synergy Strengthening and Toughening of Bio-Inspired Nacre-like Graphene Oxide/Sodium Alginate Composite Paper.

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Chen, Ke; Shi, Bin; Yue, Yonghai; Qi, Juanjuan; Guo, Lin

2015-08-25

A crucial requirement for most engineering materials is the excellent balance of strength and toughness. By mimicking the hybrid hierarchical structure in nacre, a kind of nacre-like paper based on binary hybrid graphene oxide (GO)/sodium alginate (SA) building blocks has been successfully fabricated. Systematic evaluation for the mechanical property in different (dry/wet) environment/after thermal annealing shows a perfect combination of high strength and toughness. Both of the parameters are nearly many-times higher than those of similar materials because of the synergistic strengthening/toughening enhancement from the binary GO/SA hybrids. The successful fabrication route offers an excellent approach to design advanced strong integrated nacre-like composite materials, which can be applied in tissue engineering, protection, aerospace, and permeable membranes for separation and delivery.

Design Investigation of a Laminated Waveguide Fed Multi-Band DRA for Military Applications

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Kumar, Pramod; Dwari, Santanu; Singh, Shailendra; Agrawal, N. K.

2017-12-01

In this paper a laminated waveguide fed DR Antenna is investigated. It can use for moderate power military applications. Cylindrical DRA is excited by two closely spaced asymmetric longitudinal slots on the broad wall of the laminated cavity are responsible for producing three different frequency bands. Parametric study of slots has been done with the help of commercial software ANSOFT HFSS. All the bands have sharp rejection. The final model of the antenna is simulated, fabricated and experimentally measured. Measured results are in quite accordant with design results. SIW feeding structures have small losses, moderate power handling capacity, low costs, compact sizes and can be seamlessly integrated with planar circuits. At all the bands 9.76 GHz, 10.53 GHz and 11.8 GHz resonant frequency, the antenna shows 56 MHz, 160 MHz, and 250 MHz impedance bandwidth (for VSWR<2) with 6 dB,6.2 dB and 6.8 dB gain respectively. Simulated and measured results reveal outstanding performance with a cross-polar level of 29 dB lower than that of the co-polar level at 9.76 GHz, the cross-polar level of 32 dB lower than that of the co-polar level at 10.53, GHz, and similarly cross-polar level of 30 dB lower than that of the co-polar level at 11.8 GHz.

Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition

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Christof eKuhbandner

2016-02-01

Full Text Available Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one third of the words were tested and one third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After one week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

Providing Extrinsic Reward for Test Performance Undermines Long-Term Memory Acquisition.

Science.gov (United States)

Kuhbandner, Christof; Aslan, Alp; Emmerdinger, Kathrin; Murayama, Kou

2016-01-01

Based on numerous studies showing that testing studied material can improve long-term retention more than restudying the same material, it is often suggested that the number of tests in education should be increased to enhance knowledge acquisition. However, testing in real-life educational settings often entails a high degree of extrinsic motivation of learners due to the common practice of placing important consequences on the outcome of a test. Such an effect on the motivation of learners may undermine the beneficial effects of testing on long-term memory because it has been shown that extrinsic motivation can reduce the quality of learning. To examine this issue, participants learned foreign language vocabulary words, followed by an immediate test in which one-third of the words were tested and one-third restudied. To manipulate extrinsic motivation during immediate testing, participants received either monetary reward contingent on test performance or no reward. After 1 week, memory for all words was tested. In the immediate test, reward reduced correct recall and increased commission errors, indicating that reward reduced the number of items that can benefit from successful retrieval. The results in the delayed test revealed that reward additionally reduced the gain received from successful retrieval because memory for initially successfully retrieved words was lower in the reward condition. However, testing was still more effective than restudying under reward conditions because reward undermined long-term memory for concurrently restudied material as well. These findings indicate that providing performance-contingent reward in a test can undermine long-term knowledge acquisition.

Intrinsic and extrinsic innervation of the heart in zebrafish (Danio rerio).

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Stoyek, Matthew R; Croll, Roger P; Smith, Frank M

2015-08-01

In the vertebrate heart the intracardiac nervous system is the final common pathway for autonomic control of cardiac output, but the neuroanatomy of this system is not well understood. In this study we investigated the innervation of the heart in a model vertebrate, the zebrafish. We used antibodies against acetylated tubulin, human neuronal protein C/D, choline acetyltransferase, tyrosine hydroxylase, neuronal nitric oxide synthase, and vasoactive intestinal polypeptide to visualize neural elements and their neurotransmitter content. Most neurons were located at the venous pole in a plexus around the sinoatrial valve; mean total number of cells was 197 ± 23, and 92% were choline acetyltransferase positive, implying a cholinergic role. The plexus contained cholinergic, adrenergic, and nitrergic axons and vasoactive intestinal polypeptide-positive terminals, some innervating somata. Putative pacemaker cells near the plexus showed immunoreactivity for hyperpolarization-activated cyclic nucleotide-gated channel 4 (HCN4) and the transcription factor Islet-1 (Isl1). The neurotracer neurobiotin showed that extrinsic axons from the left and right vagosympathetic trunks innervated the sinoatrial plexus proximal to their entry into the heart; some extrinsic axons from each trunk also projected into the medial dorsal plexus region. Extrinsic axons also innervated the atrial and ventricular walls. An extracardiac nerve trunk innervated the bulbus arteriosus and entered the arterial pole of the heart to innervate the proximal ventricle. We have shown that the intracardiac nervous system in the zebrafish is anatomically and neurochemically complex, providing a substrate for autonomic control of cardiac effectors in all chambers. © 2015 Wiley Periodicals, Inc.

Toughened and machinable glass matrix composites reinforced with graphene and graphene-oxide nano platelets

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Porwal, Harshit; Tatarko, Peter; Grasso, Salvatore; Hu, Chunfeng; Boccaccini, Aldo R; Dlouhý, Ivo; Reece, Mike J

2013-01-01

The processing conditions for preparing well dispersed silica–graphene nanoplatelets and silica–graphene oxide nanoplatelets (GONP) composites were optimized using powder and colloidal processing routes. Fully dense silica–GONP composites with up to 2.5 vol% loading were consolidated using spark plasma sintering. The GONP aligned perpendicularly to the applied pressure during sintering. The fracture toughness of the composites increased linearly with increasing concentration of GONP and reached a value of ∼0.9 MPa m1/2 for 2.5 vol% loading. Various toughening mechanisms including GONP necking, GONP pull-out, crack bridging, crack deflection and crack branching were observed. GONP decreased the hardness and brittleness index (BI) of the composites by ∼30 and ∼50% respectively. The decrease in BI makes silica–GONP composites machinable compared to pure silica. When compared to silica–Carbon nanotube composites, silica–GONP composites show better process-ability and enhanced mechanical properties. PMID:27877614

Tablet-level origin of toughening in abalone shells and translation to synthetic composite materials.

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Espinosa, Horacio D; Juster, Allison L; Latourte, Felix J; Loh, Owen Y; Gregoire, David; Zavattieri, Pablo D

2011-02-01

Nacre, the iridescent material in seashells, is one of many natural materials employing hierarchical structures to achieve high strength and toughness from relatively weak constituents. Incorporating these structures into composites is appealing as conventional engineering materials often sacrifice strength to improve toughness. Researchers hypothesize that nacre's toughness originates within its brick-and-mortar-like microstructure. Under loading, bricks slide relative to each other, propagating inelastic deformation over millimeter length scales. This leads to orders-of-magnitude increase in toughness. Here, we use in situ atomic force microscopy fracture experiments and digital image correlation to quantitatively prove that brick morphology (waviness) leads to transverse dilation and subsequent interfacial hardening during sliding, a previously hypothesized dominant toughening mechanism in nacre. By replicating this mechanism in a scaled-up model synthetic material, we find that it indeed leads to major improvements in energy dissipation. Ultimately, lessons from this investigation may be key to realizing the immense potential of widely pursued nanocomposites.

Extrinsic labelling of zinc and calcium in bread

International Nuclear Information System (INIS)

Fredlund, Kerstin; Rossander-Hulthen, Lena; Isaksson, Mats; Almgren, Annette; Sandberg, A.-S.

2002-01-01

This study investigated the effect of different means of extrinsic administration of 65 Zn and 47 Ca in white wheat flour bread on the measured absorption. Eight healthy subjects were served 80 g of labelled bread as a standardized breakfast after an overnight fast on three occasions. Extrinsic labelling of the meals with 65 Zn and 47 Ca was done in three ways: (a) by adding the isotopes to the bread 16 h before it was served, (b) by adding the isotopes shortly before serving or (c) by adding the isotopes to the water used in dough making. Zinc and calcium chloride corresponding to 3.2 mg (49 μmol) zinc and 275 mg (6.9 mmol) calcium in one portion were added to the dough. Whole-body retention was measured by whole-body counting. The fractional absorption of zinc was (a) 0.243±0.122, (b) 0.217±0.101 and (c) 0.178±0.063 (mean±SD), and the fractional absorption of calcium (expressed as calcium retention on day 7) was (a) 0.351±0.108, (b) 0.357±0.131 and (c) 0.334±0.117 (mean±SD). No significant difference (p>0.05) was seen between the different ways for either zinc nor calcium

Extrinsic tracheal compression caused by scoliosis of the thoracic spine and chest wall degormity: A case report

Energy Technology Data Exchange (ETDEWEB)

Baek, Kyong min Sarah; Lee, Bae Young; Kim, Hyeon Sook; Song, Kyung Sup; Kang, Hyeon Hul; Lee, Sang Haak; Moon, Hwa Sik [St. Paul' s Hospital, College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

2014-05-15

Extrinsic airway compression due to chest wall deformity is not commonly observed. Although this condition can be diagnosed more easily with the help of multidetector CT, the standard treatment method has not yet been definitely established. We report a case of an eighteen-year-old male who suffered from severe extrinsic tracheal compression due to scoliosis and straightening of the thoracic spine, confirmed on CT and bronchoscopy. The patient underwent successful placement of tracheal stent but later died of bleeding from the tracheostomy site probably due to tracheo-brachiocephalic artery fistula. We describe the CT and bronchoscopic findings of extrinsic airway compression due to chest wall deformity as well as the optimal treatment method, and discuss the possible explanation for bleeding in the patient along with review of the literature.

Extrinsic tracheal compression caused by scoliosis of the thoracic spine and chest wall degormity: A case report

International Nuclear Information System (INIS)

Baek, Kyong min Sarah; Lee, Bae Young; Kim, Hyeon Sook; Song, Kyung Sup; Kang, Hyeon Hul; Lee, Sang Haak; Moon, Hwa Sik

2014-01-01

Extrinsic airway compression due to chest wall deformity is not commonly observed. Although this condition can be diagnosed more easily with the help of multidetector CT, the standard treatment method has not yet been definitely established. We report a case of an eighteen-year-old male who suffered from severe extrinsic tracheal compression due to scoliosis and straightening of the thoracic spine, confirmed on CT and bronchoscopy. The patient underwent successful placement of tracheal stent but later died of bleeding from the tracheostomy site probably due to tracheo-brachiocephalic artery fistula. We describe the CT and bronchoscopic findings of extrinsic airway compression due to chest wall deformity as well as the optimal treatment method, and discuss the possible explanation for bleeding in the patient along with review of the literature.

Neural differences between intrinsic reasons for doing versus extrinsic reasons for doing: an fMRI study.

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Lee, Woogul; Reeve, Johnmarshall; Xue, Yiqun; Xiong, Jinhu

2012-05-01

The contemporary neural understanding of motivation is based almost exclusively on the neural mechanisms of incentive motivation. Recognizing this as a limitation, we used event-related functional magnetic resonance imaging (fMRI) to pursue the viability of expanding the neural understanding of motivation by initiating a pioneering study of intrinsic motivation by scanning participants' neural activity when they decided to act for intrinsic reasons versus when they decided to act for extrinsic reasons. As expected, intrinsic reasons for acting more recruited insular cortex activity while extrinsic reasons for acting more recruited posterior cingulate cortex (PCC) activity. The results demonstrate that engagement decisions based on intrinsic motivation are more determined by weighing the presence of spontaneous self-satisfactions such as interest and enjoyment while engagement decisions based on extrinsic motivation are more determined by weighing socially-acquired stored values as to whether the environmental incentive is attractive enough to warrant action.

Extrinsic labelling of staple food crops with isotopic iron does not consistently result in full equilibration: Revisiting the methodology

Science.gov (United States)

Extrinsic isotopic labeling of food Fe has been used for over 50 years to measure Fe absorption. This method is based on the assumption that complete equilibration occurs between the extrinsic and the intrinsic Fe prior to intestinal absorption. The present study tested this assumption via use of in...

Intrinsic and extrinsic influences on children's acceptance of new foods.

Science.gov (United States)

Blissett, Jackie; Fogel, Anna

2013-09-10

The foods that tend to be rejected by children include those which may have greatest importance for later health. This paper reviews some of the intrinsic and extrinsic influences on preschool children's eating behavior, with particular reference to their acceptance of new foods into their diet. Factors conceptualized as intrinsic to the child in this review include sensory processing, taste perception, neophobia, and temperament. The important extrinsic determinants of children's food acceptance which are reviewed include parental and peer modeling, the family food environment, infant feeding practices including breastfeeding and age at weaning, concurrent feeding practices including restriction, pressure to eat, prompting and reward, and the taste & energy content of foods. Children's willingness to accept new foods is influenced by a wide range of factors that likely have individual and also interactive effects on children's willingness to taste, and then continue to eat, new foods. The literature lacks longitudinal and experimental studies, which will be particularly important in determining interventions most likely to be effective in facilitating children's acceptance of healthy foods. Copyright © 2013 Elsevier Inc. All rights reserved.

Cardiac extrinsic apoptotic pathway is silent in young but activated in elder mice overexpressing bovine GH: interplay with the intrinsic pathway.

Science.gov (United States)

Bogazzi, Fausto; Russo, Dania; Raggi, Francesco; Bohlooly-Y, Mohammad; Tornell, Jan; Sardella, Chiara; Lombardi, Martina; Urbani, Claudio; Manetti, Luca; Brogioni, Sandra; Martino, Enio

2011-08-01

Apoptosis may occur through the mitochondrial (intrinsic) pathway and activation of death receptors (extrinsic pathway). Young acromegalic mice have reduced cardiac apoptosis whereas elder animals have increased cardiac apoptosis. Multiple intrinsic apoptotic pathways have been shown to be modulated by GH and other stimuli in the heart of acromegalic mice. However, the role of the extrinsic apoptotic pathways in acromegalic hearts is currently unknown. In young (3-month-old) acromegalic mice, expression of proteins of the extrinsic apoptotic pathway did not differ from that of wild-type animals, suggesting that this mechanism did not participate in the lower cardiac apoptosis levels observed at this age. On the contrary, the extrinsic pathway was active in elder (9-month-old) animals (as shown by increased expression of TRAIL, FADD, TRADD and increased activation of death inducing signaling complex) leading to increased levels of active caspase 8. It is worth noting that changes of some pro-apoptotic proteins were induced by GH, which seemed to have, in this context, pro-apoptotic effects. The extrinsic pathway influenced the intrinsic pathway by modulating t-Bid, the cellular levels of which were reduced in young and increased in elder animals. However, in young animals this effect was due to reduced levels of Bid regulated by the extrinsic pathway, whereas in elder animals the increased levels of t-Bid were due to the increased levels of active caspase 8. In conclusion, the extrinsic pathway participates in the cardiac pro-apoptotic phenotype of elder acromegalic animals either directly, enhancing caspase 8 levels or indirectly, increasing t-Bid levels and conveying death signals to the intrinsic pathway.

Alteration in intrinsic and extrinsic functional connectivity of resting state networks associated with subclinical hypothyroid.

Science.gov (United States)

Kumar, Mukesh; Modi, Shilpi; Rana, Poonam; Kumar, Pawan; Kanwar, Ratnesh; Sekhri, Tarun; D'souza, Maria; Khushu, Subash

2018-03-05

Subclinical hypothyroidism (SCH) is characterized by mild elevation of thyroid stimulating hormone (TSH) (range 5-10 μIU/ml) and normal free triiodothyronine (FT3) and free thyroxine (FT4). The cognitive function impairment is well known in thyroid disorders such as hypothyroidism and hyperthyroidism, but little is known about deficits in brain functions in SCH subjects. Also, whether hormone-replacement treatment is necessary or not in SCH subjects is still debatable. In order to have an insight into the cognition of SCH subjects, intrinsic and extrinsic functional connectivity (FC) of the resting state networks (RSNs) was studied. For resting state data analysis we used an unbiased, data-driven approach based on Independent Component Analysis (ICA) and dual-regression that can emphasize widespread changes in FC without restricting to a set of predefined seeds. 28 SCH subjects and 28 matched healthy controls (HC) participated in the study. RSN analysis showed significantly decreased intrinsic FC in somato-motor network (SMN) and right fronto-parietal attention network (RAN) and increased intrinsic FC in default mode network (DMN) in SCH subjects as compared to control subjects. The reduced intrinsic FC in the SMN and RAN suggests neuro-cognitive alterations in SCH subjects in the corresponding functions which were also evident from the deficit in the neuropsychological performance of the SCH subjects on behavioural tests such as digit span, delayed recall, visual retention, recognition, Bender Gestalt and Mini-Mental State Examination (MMSE). We also found a significant reduction in extrinsic network FC between DMN and RAN; SMN and posterior default mode network (PDMN); and increased extrinsic FC between SMN and anterior default mode network (ADMN) in SCH subjects as compared to controls. An altered extrinsic FC in SCH suggests functional reorganization in response to neurological disruption. The partial correlation analysis between intrinsic and extrinsic RSNs

Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems

Directory of Open Access Journals (Sweden)

Joschka eBoedecker

2013-10-01

Full Text Available A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the prefrontal and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

Modeling effects of intrinsic and extrinsic rewards on the competition between striatal learning systems.

Science.gov (United States)

Boedecker, Joschka; Lampe, Thomas; Riedmiller, Martin

2013-01-01

A common assumption in psychology, economics, and other fields holds that higher performance will result if extrinsic rewards (such as money) are offered as an incentive. While this principle seems to work well for tasks that require the execution of the same sequence of steps over and over, with little uncertainty about the process, in other cases, especially where creative problem solving is required due to the difficulty in finding the optimal sequence of actions, external rewards can actually be detrimental to task performance. Furthermore, they have the potential to undermine intrinsic motivation to do an otherwise interesting activity. In this work, we extend a computational model of the dorsomedial and dorsolateral striatal reinforcement learning systems to account for the effects of extrinsic and intrinsic rewards. The model assumes that the brain employs both a goal-directed and a habitual learning system, and competition between both is based on the trade-off between the cost of the reasoning process and value of information. The goal-directed system elicits internal rewards when its models of the environment improve, while the habitual system, being model-free, does not. Our results account for the phenomena that initial extrinsic reward leads to reduced activity after extinction compared to the case without any initial extrinsic rewards, and that performance in complex task settings drops when higher external rewards are promised. We also test the hypothesis that external rewards bias the competition in favor of the computationally efficient, but cruder and less flexible habitual system, which can negatively influence intrinsic motivation and task performance in the class of tasks we consider.

Intrinsic and extrinsic electrical and thermal transport of bulk black phosphorus

Science.gov (United States)

Hu, Sile; Xiang, Junsen; Lv, Meng; Zhang, Jiahao; Zhao, Hengcan; Li, Chunhong; Chen, Genfu; Wang, Wenhong; Sun, Peijie

2018-01-01

We report a comprehensive investigation of the electrical, thermal, and thermoelectric transport properties of bulk single-crystalline black phosphorus in wide temperature (2-300 K) and field (0-9 T) ranges. Electrical transport below T ≈ 250 K is found to be dominated by extrinsic hole-type charge carriers with large mobility exceeding 104 cm2/V s at low temperatures. While thermal transport measurements reveal an enhanced in-plane thermal conductivity maximum κ = 180 W/m K at T ≈ 25 K, it appears still to be largely constrained by extrinsic phonon scattering processes, e.g., the electron-phonon process, in addition to intrinsic umklapp scattering. The thermoelectric power and Nernst effect seem to be strongly influenced by ambipolar transport of charge carriers with opposite signs in at least the high-temperature region above 200 K, which diminishes the thermoelectric power factor of this material. Our results provide a timely update to the transport properties of bulk black phosphorus for future fundamental and applied research.

Long-term Spot-Coverage Variations of 13 BY Dra G-K Dwarfs

Science.gov (United States)

Alekseev, I. Yu.; Kozhevnikova, A. V.

2018-06-01

The results of spot-coverage modeling for 13 active G-K dwarf stars based on many-year photometric observations are presented. The results of UBV RI observations of eight stars performed at the Crimean Astrophysical Observatory were used together with data from the literature in this analysis. The spot-coverage parameters for 13 selected BY Dra active red dwarfs have been redetermined to improve the zonal spot-coverage model for the stellar photospheres, which currently allows for the presence of two active longitudes. Time variations of the spot-activity characteristics of these systems were analyzed with the aim of searching for possible cyclic variations. All the stars, with the exception of OU Gem and BE Cet, show fairly strong correlations between variations in the spot latitudes and spot areas, with absolute values of the correlation coefficients, R(, S), ranging from 0.38 to 0.92. For five stars, an anti-correlation between the mean latitude and area of the spots was found ( R(, S) from-0.24 to-0.73). This behavior may reflect the drift of spots toward the equator in the course of their development. Eight stars feature positive correlations, i.e. the spots drift towards the pole as their areas increase. Nine stars demonstrate activity cycles, which are reflected in photometric variations as well as variations of the spot areas and mean latitudes. The periods of the latitude drift of the spots are found for five stars; the magnitudes of the spot-latitude drift rates are lower than the corresponding value for sunspots by a factor of 1.5-3.

The Influence of Intrinsic and Extrinsic Rewards on Employee Results: An Empirical Analysis in Turkish Manufacturing Industry

OpenAIRE

Ozutku, Hatice

2012-01-01

The study discussed in this article questions whether certain reward practices used by organizations are better than others when comparing the employee results based on TQM. We first examine reward systems and TQM relevant literature. After related literature review, reward practices have been handled in two groups as intrinsic rewards and extrinsic rewards. In the sample, which consists of 217 businesses that operate in Turkish manufacturing industry and apply TQM, intrinsic and extrinsic re...

Common region wins the competition between extrinsic grouping cues: Evidence from a task without explicit attention to grouping.

Science.gov (United States)

Montoro, Pedro R; Villalba-García, Cristina; Luna, Dolores; Hinojosa, José A

2017-12-01

The competition between perceptual grouping factors is a relatively ignored topic, especially in the case of extrinsic grouping cues (e.g., common region or connectedness). Recent studies have examined the integration of extrinsic cues using tasks that induce selective attention to groups based on different grouping cues. However, this procedure could generate alternative strategies for task performance, which are non-related to the perceptual grouping operations. In the current work, we used an indirect task, i.e. repetition discrimination task, without explicit attention to grouping cues to further examine the rules that govern dominance between competing extrinsic grouping factors. This procedure allowed us to obtain an unbiased measure of the competition between common region and connectedness cues acting within the same display. The results corroborate previous data showing that grouping by common region dominated the perceived organization of the display, even though the phenomenological strength of the grouping cues was equated for each participant by means of a preliminary scaling task. Our results highlight the relevance of using indirect tasks as an essential tool for the systematic study of the integration of extrinsic grouping cues.

The infrared flux method and its use for study of α Boo, μ Her and β Dra; relation to the Vega 1.2-5 μm infrared excess

International Nuclear Information System (INIS)

Blackwell, D.E.; Booth, A.J.; Petford, A.D.; Leggett, S.K.; Mountain, C.M.; Selby, M.J.

1986-01-01

The effective temperatures of α Boo, μ Her, and β Dra are determined using the infrared flux method. The determinations are based on the high-quality spectrophotometric data obtained from an aircraft by previous authors, the new infrared calibration of Vega obtained from observations made at Tenerife between 1979 and 1983, the use of a Reticon spectrometer to determine the integrated fluxes in the region 370-950 nm, and the use of model atmospheres constructed with the previously developed MARCS code. (author)

Self-Perception of Intrinsic and Extrinsic Motivation: Effects on Institutionalized Mentally Retarded Adolescents

Science.gov (United States)

Lee, Dong Yul; And Others

1977-01-01

The self-perception theory which predicts that the introduction of extrinsic rewards for behavior that was intrinsically rewarding may decrease overall motivation was tested on 44 mildly retarded institutionalized adolescents. (Author/CL)

Ipsilateral wrist-ankle movements in the sagittal plane encoded in extrinsic reference frame.

Science.gov (United States)

Muraoka, Tetsuro; Ishida, Yuki; Obu, Takashi; Crawshaw, Larry; Kanosue, Kazuyuki

2013-04-01

When performing oscillatory movements of two joints in the sagittal plane, there is a directional constraint for performing such movements. Previous studies could not distinguish whether the directional constraint reflected movement direction encoded in the extrinsic (outside the body) reference frame or in the intrinsic (the participants' torso/head) reference frame since participants performed coordinated movements in a sitting position where the torso/head was stationary relative to the external world. In order to discern the reference frame in the present study, participants performed paced oscillatory movements of the ipsilateral wrist and ankle in the sagittal plane in a standing position so that the torso/head moved relative to the external world. The coordinated movements were performed in one of two modes of coordination, moving the hand upward concomitant with either ankle plantarflexion or ankle dorsiflexion. The same directional mode relative to extrinsic space was more stable and accurate as compared with the opposite directional mode. When forearm position was changed from the pronated position to the supinated position, similar results were obtained, indicating that the results were independent of a particular coupling of muscles. These findings suggest that the directional constraint on ipsilateral joints movements in the sagittal plane reflects movement direction encoded in the extrinsic reference frame. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Comparing Effects of Intrinsic and Extrinsic Social Values Between Younger and Older Employees.

Science.gov (United States)

Yeung, Dannii Y; Fung, Helene H; Chan, Darius K-S

2016-08-17

Socioemotional selectivity theory proposes that older adults emphasize emotional goals and interpersonal closeness to a greater extent than do younger adults, suggesting that holding social work-related values (SWVs) may be beneficial to older employees. This project aimed at examining two dimensions of SWVs, intrinsic and extrinsic SWVs, and tested whether age and work situation would moderate their effects on self-rated job performance. A cross-sectional survey (Study 1, N = 357) and a 14-day experience sampling study (Study 2, N = 77) were conducted among Chinese managerial employees. Study 1 showed that the direct effect of intrinsic SWVs on self-rated job performance was stronger in older employees than in younger employees. Study 2 demonstrated that older employees who valued intrinsic SWVs while being in social situations performed much better than when they did not value intrinsic SWVs but being in social situations; however such positive effect was not shown in younger employees. Findings of this project reveal that the effect of SWVs varies across locus of effect (intrinsic versus extrinsic), age, and work situation. Among older employees, the positive effect of intrinsic SWVs is more crucial than that of extrinsic SWVs on self-rated job performance. Findings of this project imply that intrinsically rewarding incentives would be more effective in motivating older employees to reach peak performance.

CD147 regulates extrinsic apoptosis in spermatocytes by modulating NFκB signaling pathways.

Science.gov (United States)

Wang, Chaoqun; Fok, Kin Lam; Cai, Zhiming; Chen, Hao; Chan, Hsiao Chang

2017-01-10

CD147 null mutant male mice are infertile with arrested spermatogenesis and increased apoptotic germ cells. Our previous studies have shown that CD147 prevents apoptosis in mouse spermatocytes but not spermatogonia. However, the underlying mechanism remains elusive. In the present study, we aim to determine the CD147-regulated apoptotic pathway in mouse spermatocytes. Our results showed that immunodepletion of CD147 triggered apoptosis through extrinsic apoptotic pathway in mouse testis and spermatocyte cell line (GC-2 cells), accompanied by activation of non-canonical NFκB signaling and suppression of canonical NFκB signaling. Furthermore, CD147 was found to interact with TRAF2, a factor known to regulate NFκB and extrinsic apoptotic signaling, and interfering CD147 led to the decrease of TRAF2. Consistently, depletion of CD147 by CRISPR/Cas9 technique in GC-2 cells down-regulated TRAF2 and resulted in cell death with suppressed canonical NFκB and activated non-canonical NFκB signaling. On the contrary, interfering of CD147 had no effect on NFκB signaling pathways as well as TRAF2 protein level in mouse spermatogonia cell line (GC-1 cells). Taken together, these results suggested that CD147 plays a key role in reducing extrinsic apoptosis in spermatocytes, but not spermatogonia, through modulating NFκB signaling pathway.

Teacher Work Motivation in the Era of Extrinsic Incentives: Performance Goals and Pro-Social Commitments in the Service of Equity

Science.gov (United States)

Mintrop, Rick; Ordenes, Miguel

2017-01-01

Mindful of the withering of high-stakes accountability and disappointing data from pay for performance evaluations in the US, we ask why management by extrinsic incentives and organizational goal setting may have been far less powerful than designers of accountability and extrinsic incentive systems had expected. We explore how…

Exploring Intrinsic and Extrinsic Motivations to Participate in a Crowdsourcing Project to Support Blind and Partially Sighted Students.

Science.gov (United States)

Layas, Fatma; Petrie, Helen

2016-01-01

There have been a number of crowdsourcing projects to support people with disabilities. However, there is little exploration of what motivates people to participate in such crowdsourcing projects. In this study we investigated how different motivational factors can affect the participation of people in a crowdsourcing project to support visually disabled students. We are developing "DescribeIT", a crowdsourcing project to support blind and partially students by having sighted people describe images in digital learning resources. We investigated participants' behavior of the DescribeIT project using three conditions: one intrinsic motivation condition and two extrinsic motivation conditions. The results showed that participants were significantly intrinsically motivated to participate in the DescribeIT project. In addition, participants' intrinsic motivation dominated the effect of the two extrinsic motivational factors in the extrinsic conditions.

Improved children's motor learning of the basketball free shooting pattern by associating subjective error estimation and extrinsic feedback.

Science.gov (United States)

Silva, Leandro de Carvalho da; Pereira-Monfredini, Carla Ferro; Teixeira, Luis Augusto

2017-09-01

This study aimed at assessing the interaction between subjective error estimation and frequency of extrinsic feedback in the learning of the basketball free shooting pattern by children. 10- to 12-year olds were assigned to 1 of 4 groups combining subjective error estimation and relative frequency of extrinsic feedback (33% × 100%). Analysis of performance was based on quality of movement pattern. Analysis showed superior learning of the group combining error estimation and 100% feedback frequency, both groups receiving feedback on 33% of trials achieved intermediate results, and the group combining no requirement of error estimation and 100% feedback frequency had the poorest learning. Our results show the benefit of subjective error estimation in association with high frequency of extrinsic feedback in children's motor learning of a sport motor pattern.

Text Summarization Evaluation: Correlating Human Performance on an Extrinsic Task with Automatic Intrinsic Metrics

National Research Council Canada - National Science Library

President, Stacy F; Dorr, Bonnie J

2006-01-01

This research describes two types of summarization evaluation methods, intrinsic and extrinsic, and concentrates on determining the level of correlation between automatic intrinsic methods and human...

New insights into insight: Neurophysiological correlates of the difference between the intrinsic "aha" and the extrinsic "oh yes" moment.

Science.gov (United States)

Rothmaler, Katrin; Nigbur, Roland; Ivanova, Galina

2017-01-27

Insight refers to a situation in which a problem solver immediately changes his understanding of a problem situation. This representational change can either be triggered by external stimuli, like a hint or the solution itself, or by internal solution attempts. In the present paper, the differences and similarities between these two phenomena, namely "extrinsic" and "intrinsic" insight, are examined. To this end, electroencephalogram (EEG) is recorded while subjects either recognize or generate solutions to German verbal compound remote associate problems (CRA). Based on previous studies, we compare the alpha power prior to insightful solution recognition with the alpha power prior to insightful solution generation. Results show that intrinsic insights are preceded by an increase in alpha power at right parietal electrodes, while extrinsic insights are preceded by a respective decrease. These results can be interpreted in two ways. In consistency with other studies, the increase in alpha power before intrinsic insights can be interpreted as an increased internal focus of attention. Accordingly, the decrease in alpha power before extrinsic insights may be associated with a more externally oriented focus of attention. Alternatively, the increase in alpha power prior to intrinsic insights can be interpreted as an active inhibition of solution-related information, while the alpha power decrease prior to extrinsic insights may reflect its activation. Regardless of the interpretation, the results provide strong evidence that extrinsic and intrinsic insight differ on the behavioral as well as the neurophysiological level. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analysis of extrinsic and intrinsic factors that predispose elderly individuals to fall.

Science.gov (United States)

Almeida, Sionara Tamanini de; Soldera, Cristina Loureiro Chaves; Carli, Geraldo Attilio de; Gomes, Irênio; Resende, Thais de Lima

2012-01-01

In a sample of elderly individuals from Porto Alegre - RS, Brazil, to analyze the intrinsic and extrinsic factors that predispose them to the risk of falls and fractures. The study included a random sample of 267 elderly individuals, to whom two balance tests were applied: the Functional Reach Test (FRT) and the Timed Up and Go Test (TUG). The elderly also answered a questionnaire (13 questions divided into four categories) on sociodemographic and health factors. Elderly individuals from both genders (76.8% women), aged between 60 and 90 years (mean = 70.22 years, SD = ± 7.30 years) participated in the study. A statistically significant association (p factors that predispose to the risk of falls and fractures are older age, poor self-perception of eyesight, and poor selfrated health; the extrinsic factors are type of dwelling (living in a house) and a monthly income < one minimum wage.

How Does Intrinsic and Extrinsic Motivation Drive Performance Culture in Organizations?

Science.gov (United States)

Turner, Arielle

2017-01-01

The performance culture of an organization is impacted by the motivation of an organization's employee. Determining whether or not an employee's motivation is intrinsic or extrinsic is helpful for organizations to see what is more of a drive in their performance. The following article reviews literature on the subject of employee motivation to…

Extrinsic factors promoting insulin producing cell-differentiation and insulin expression enhancement-hope for diabetics.

Science.gov (United States)

Dave, Shruti

2013-11-01

Diabetes mellitus (DM) is considered to be an autoimmune disorder leading to destruction of beta-cells resulting in to a loss of blood sugar control. Attempts using many pharmacological compositions including exogenous insulin have failed to show tight control of glycemia and associated manifestations. Stem cells are considered a potential tool for the supply of insulin-producing cells (IPC) generation in vitro. Stem cell differentiation in to pancreatic lineages requires influence of both intrinsic and extrinsic factors. Application of islet growth factors is considered to be potential for enhancement of beta-cell replication, function and survival. Use of certain extrinsic factors is known to facilitate expression of transcription factors known to be important for beta-cell differentiation and production of insulin enabling IPC generation. Hierarchies of secreted signals and transcription factors have been identified by studies from several laboratories that guide cell differentiation in to IPC. This knowledge provides insights for in vitro IPC differentiation from stem cells. Current advancement in medical knowledge promises an insulin independency for DM patients. The review sheds light on few specific extrinsic factors which facilitate differentiation of stem cells in to IPC in vitro have been discussed; which can be proven as a potential therapeutic option for treatment of DM and associated diseases.

Surface modifications on toughened, fine-grained, recrystallized tungsten with repetitive ELM-like pulsed plasma irradiation

Energy Technology Data Exchange (ETDEWEB)

Kikuchi, Y., E-mail: ykikuchi@eng.u-hyogo.ac.jp [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, 671-2280 Hyogo (Japan); Sakuma, I.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M. [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, 671-2280 Hyogo (Japan); Ueda, Y. [Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Kurishita, H. [Institute for Materials Research, Tohoku University, Ibaraki 311-1313 (Japan)

2015-08-15

Surface modifications of toughened, fine-grained, recrystallized tungsten (TFGR W) materials with 1.1 wt.% TiC and 3.3 wt.% TaC dispersoids due to repetitive ELM-like pulsed (∼0.15 ms) helium plasma irradiation have been investigated by using a magnetized coaxial plasma gun. No surface cracking at the center part of the TFGR W samples exposed to 20 plasma pulses of ∼0.3 MJ m{sup −2} was observed. The suppression of surface crack formation due to the increase of the grain boundary strength by addition of TiC and TaC dispersoids was confirmed in comparison with a pure W material. On the other hand, surface cracks and small pits appeared at the edge part of the TFGR W sample after the pulsed plasma irradiation. Erosion of the TiC and TaC dispersoids due to the pulsed plasma irradiation could cause the small pits on the surface, resulting in the surface crack formation.

Surface modifications on toughened, fine-grained, recrystallized tungsten with repetitive ELM-like pulsed plasma irradiation

Science.gov (United States)

Kikuchi, Y.; Sakuma, I.; Kitagawa, Y.; Asai, Y.; Onishi, K.; Fukumoto, N.; Nagata, M.; Ueda, Y.; Kurishita, H.

2015-08-01

Surface modifications of toughened, fine-grained, recrystallized tungsten (TFGR W) materials with 1.1 wt.% TiC and 3.3 wt.% TaC dispersoids due to repetitive ELM-like pulsed (∼0.15 ms) helium plasma irradiation have been investigated by using a magnetized coaxial plasma gun. No surface cracking at the center part of the TFGR W samples exposed to 20 plasma pulses of ∼0.3 MJ m-2 was observed. The suppression of surface crack formation due to the increase of the grain boundary strength by addition of TiC and TaC dispersoids was confirmed in comparison with a pure W material. On the other hand, surface cracks and small pits appeared at the edge part of the TFGR W sample after the pulsed plasma irradiation. Erosion of the TiC and TaC dispersoids due to the pulsed plasma irradiation could cause the small pits on the surface, resulting in the surface crack formation.

Intraoperative inspection of the ureteropelvic junction during pyeloplasty is not sufficient to distinguish between extrinsic and intrinsic causes of obstruction: Correlation with histological analysis.

Science.gov (United States)

Mut, Tuna; Acar, Ömer; Oktar, Tayfun; Kılıçaslan, Işın; Esen, Tarık; Ander, Haluk; Ziylan, Orhan

2016-08-01

Based on current knowledge, it is possible to have an initial diagnosis of intrinsic or extrinsic ureteropelvic junction obstruction (UPJO) based solely on clinical and imaging findings. However, it may not be possible to strictly discriminate an intrinsic case with an additional extrinsic component from a primarily intrinsic stenosis because of lower pole aberrant vessels. These two disorders may coexist or trigger each other. Herein, we aimed to compare the histological changes observed in intrinsic and extrinsic types of UPJO. Our hypothesis is that inspecting the UPJ during pyeloplasty may not be a sufficient way to delineate the underlying cause of obstruction in every individual. We retrospectively reviewed the data of 56 patients who had dismembered pyeloplasty. The intrinsic and extrinsic groups consisted of 38 and 18 patients, respectively. Masson's trichrome stain, CD117, and connexin 43 (Cx43) antibody were used in histopathology and immunochemistry. Statistical calculations were done with chi-square and Mann-Whitney U tests. Connexin 43 staining pattern, CD117 positive cell count, and the extent of fibrosis did not differ significantly between extrinsic and intrinsic cases. However, the difference with regard to the degree of muscular hypertrophy was close to statistical significance. The exact pathophysiological mechanism underlying UPJO has yet to be elucidated. A study directly comparing both groups histologically is indeed rare. Our study showed that there are no significant differences between the intrinsic and extrinsic groups in terms of the pacemaker activity, gap junctional communication, and extent of fibrosis. Muscular hypertrophy, which was marginally higher in our extrinsic group, may persist despite successful relocation of the obstructing vessel. The main drawbacks of our study are; the absence of a control group and the retrospective study design with its inherent selection biases. Immunohistochemical profiles of intrinsic and extrinsic

First principles studies of extrinsic and intrinsic defects in boron nitride nanotubes

CSIR Research Space (South Africa)

Mashapa, MG

2012-10-01

Full Text Available -1 Journal of Nanoscience and Nanotechnology 2012/ Vol. 12, 7807?7814 First Principles Studies of Extrinsic and Intrinsic Defects in Boron Nitride Nanotubes M. G. Mashapa 1, 2, ?, N. Chetty1, and S. Sinha Ray2, 3 1Physics Department, University...

Comparing Intrinsic and Extrinsic Evaluation of MT Output in a Dialogue System.

NARCIS (Netherlands)

van der Sluis, Ielka; Luz, S.; Schneider, A.

2010-01-01

We present an exploratory study to assess machine translation output for application in a dialogue system using an intrinsic and an extrinsic evaluation method. For the intrinsic evaluation we developed an annotation scheme to determine the quality of the translated utterances in isolation. For the

Ductile-phase toughening in V-V3Si in situ composites

International Nuclear Information System (INIS)

Henshall, G.; Strum, M.J.; Bewlay, B.P.; Sutliff, J.A.

1997-01-01

This article describes the room-temperature fracture behavior of ductile-phase-toughened V-V 3 Si in situ composites that were produced by arc melting (AM), cold-crucible induction melting (IM), and cold-crucible directional solidification (DS). Composites were produced containing a wide range of microstructures, interstitial impurity contents, and volume fractions of the ductile V-Si solid solution phase, denoted (V). The fracture toughness of these composites generally increases as the volume fraction of (V) increases, but is strongly influenced by the microstructure, the mechanical properties of the component phases, and the crystallographic orientation of the (V) phase with respect to the maximum principal stress direction. For eutectic composites that have a (V) volume fraction of about 50 pct, the fracture toughness increases with decreasing ''''effective'''' interstitial impurity concentration, [I] = [N] + 1.33 [O] + 9 [H]. As [I] decreases from 1,400 ppm (AM) to 400 ppm (IM), the fracture toughness of the eutectic composites increases from 10 to 20 MPa √m. Further, the fracture toughness of the DS eutectic composites is greater when the crack propagation direction is perpendicular, rather than parallel, to the composite growth direction. These results are discussed in light of conventional ductile-phase bridging theories, which alone cannot fully explain the fracture toughness of V-Si in situ composites

Expression of Fas, FasL, caspase-8 and other factors of the extrinsic apoptotic pathway during the onset of interdigital tissue elimination.

Science.gov (United States)

Svandova, E Budisova; Vesela, B; Lesot, H; Poliard, A; Matalova, E

2017-04-01

Elimination of the interdigital web is considered to be the classical model for assessing apoptosis. So far, most of the molecules described in the process have been connected to the intrinsic (mitochondrial) pathway. The extrinsic (receptor mediated) apoptotic pathway has been rather neglected, although it is important in development, immunomodulation and cancer therapy. This work aimed to investigate factors of the extrinsic apoptotic machinery during interdigital regression with a focus on three crucial initiators: Fas, Fas ligand and caspase-8. Immunofluorescent analysis of mouse forelimb histological sections revealed abundant expression of these molecules prior to digit separation. Subsequent PCR Array analyses indicated the expression of several markers engaged in the extrinsic pathway. Between embryonic days 11 and 13, statistically significant increases in the expression of Fas and caspase-8 were observed, along with other molecules involved in the extrinsic apoptotic pathway such as Dapk1, Traf3, Tnsf12, Tnfrsf1A and Ripk1. These results demonstrate for the first time the presence of extrinsic apoptotic components in mouse limb development and indicate novel candidates in the molecular network accompanying the regression of interdigital tissue during digitalisation.

Substance use by college students: the role of intrinsic versus extrinsic motivation for athletic involvement.

Science.gov (United States)

Rockafellow, Bradley D; Saules, Karen K

2006-09-01

Certain types of athletic involvement may confer risk for substance use by college students. This study investigated whether motivational factors play a role in the relationship between athletic involvement and substance use. Intercollegiate athletes (n=98) and exercisers (n=120) were surveyed about substance use and motivation for athletic involvement. Athletes and exercisers who were extrinsically motivated had significantly higher rates of alcohol use than their intrinsically motivated counterparts. Results suggest that college students who are extrinsically motivated for involvement in physical activity/athletics--particularly those involved in team sports--may be in need of targeted prevention efforts. ((c) 2006 APA, all rights reserved).

Intrinsic and extrinsic diffusion of phosphorus, arsenic, and antimony in germanium

International Nuclear Information System (INIS)

Brotzmann, Sergej; Bracht, Hartmut

2008-01-01

Diffusion experiments of phosphorus (P), arsenic (As), and antimony (Sb) in high purity germanium (Ge) were performed at temperatures between 600 and 920 deg. C. Secondary ion mass spectrometry and spreading resistance profiling were applied to determine the concentration profiles of the chemically and electrically active dopants. Intrinsic and extrinsic doping conditions result in a complementary error function and box-shaped diffusion profiles, respectively. These profiles demonstrate enhanced dopant diffusion under extrinsic doping. Accurate modeling of dopant diffusion is achieved on the basis of the vacancy mechanism taking into account singly negatively charged dopant-vacancy pairs and doubly negatively charged vacancies. The activation enthalpy and pre-exponential factor for dopant diffusion under intrinsic condition were determined to 2.85 eV and 9.1 cm 2 s -1 for P, 2.71 eV and 32 cm 2 s -1 for As, and 2.55 eV and 16.7 cm 2 s -1 for Sb. With increasing atomic size of the dopants the activation enthalpy decreases. This is attributed to differences in the binding energy of the dopant-vacancy pairs

Implications of Self-Deception for Self-Reported Intrinsic and Extrinsic Motivational Dispositions and Actual Learning Performance: A Higher Order Structural Model

Science.gov (United States)

Hirschfeld, Robert R.; Thomas, Christopher H.; McNatt, D. Brian

2008-01-01

The authors explored implications of individuals' self-deception (a trait) for their self-reported intrinsic and extrinsic motivational dispositions and their actual learning performance. In doing so, a higher order structural model was developed and tested in which intrinsic and extrinsic motivational dispositions were underlying factors that…

Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple.

Science.gov (United States)

Gitto, Salvatore; Messina, Carmelo; Mauri, Giovanni; Aliprandi, Alberto; Sardanelli, Francesco; Sconfienza, Luca Maria

2017-02-01

Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Profiles of Intrinsic and Extrinsic Motivations in Elementary School: A Longitudinal Analysis

Science.gov (United States)

Corpus, Jennifer Henderlong; Wormington, Stephanie V.

2014-01-01

The authors used a person-centered, longitudinal approach to identify and evaluate naturally occurring combinations of intrinsic and extrinsic motivations among 490 third- through fifth-grade students. Cluster analysis revealed 3 groups, characterized by high levels of both motivations ("high quantity"): high intrinsic motivation but low…

Promoting Intrinsic and Extrinsic Motivation among Chemistry Students Using Computer-Assisted Instruction

Science.gov (United States)

Gambari, Isiaka A.; Gbodi, Bimpe E.; Olakanmi, Eyitao U.; Abalaka, Eneojo N.

2016-01-01

The role of computer-assisted instruction in promoting intrinsic and extrinsic motivation among Nigerian secondary school chemistry students was investigated in this study. The study employed two modes of computer-assisted instruction (computer simulation instruction and computer tutorial instructional packages) and two levels of gender (male and…

Extrinsic versus intrinsic ferroelectric switching: experimental investigations using ultra-thin PVDF Langmuir-Blodgett films

International Nuclear Information System (INIS)

Kliem, H; Tadros-Morgane, R

2005-01-01

Mechanisms of extrinsic and intrinsic switching phenomena in ferroelectrics are explained and existing models are summarized. Then, criteria for an experimental distinction between both models are elaborated. Samples with thicknesses ranging from 2.7 to 63.8 nm prepared by a Langmuir-Blodgett technique were investigated with respect to these criteria. Measurements of their polarization switching behaviour, their polarization hysteresis loops, and their coercive fields were carried out. It is found that the coercive fields increase with decreasing sample thickness. Also, the switching time increases with decreasing sample thickness and it increases with decreasing field strength. The switching process turns out to be thermally activated. We find that neither intrinsic nor extrinsic models are sufficient to describe the experimental situation

Comparison of skin barrier function and sensory nerve electric current perception threshold between IgE-high extrinsic and IgE-normal intrinsic types of atopic dermatitis.

Science.gov (United States)

Mori, T; Ishida, K; Mukumoto, S; Yamada, Y; Imokawa, G; Kabashima, K; Kobayashi, M; Bito, T; Nakamura, M; Ogasawara, K; Tokura, Y

2010-01-01

Background Two types of atopic dermatitis (AD) have been proposed, with different pathophysiological mechanisms underlying this seemingly heterogeneous disorder. The extrinsic type shows high IgE levels presumably as a consequence of skin barrier damage and feasible allergen permeation, whereas the intrinsic type exhibits normal IgE levels and is not mediated by allergen-specific IgE. Objectives To investigate the relationship between pruritus perception threshold and skin barrier function of patients with AD in a comparison between the extrinsic and intrinsic types. Methods Enrolled in this study were 32 patients with extrinsic AD, 17 with intrinsic AD and 24 healthy individuals. The barrier function of the stratum corneum was assessed by skin surface hydration and transepidermal water loss (TEWL), and pruritus perception was evaluated by the electric current perception threshold (CPT) of sensory nerves upon neuroselective transcutaneous electric stimulation. Results Skin surface hydration was significantly lower and TEWL was significantly higher in extrinsic AD than intrinsic AD or normal controls. Although there was no statistically significant difference in CPT among extrinsic AD, intrinsic AD and normal controls, CPT was significantly correlated with skin surface hydration and inversely with TEWL in intrinsic AD and normal controls, but not extrinsic AD. Finally, CPT was correlated with the visual analogue scale of itch in the nonlesional skin of patients with extrinsic but not intrinsic AD. Conclusions Patients with extrinsic AD have an impaired barrier, which increases the pre-existing pruritus but rather decreases sensitivity to external stimuli. In contrast, patients with intrinsic AD retain a normal barrier function and sensory reactivity to external pruritic stimuli.

Are competition and extrinsic motivation reliable predictors of academic cheating?

OpenAIRE

Gábor eOrosz; Gábor eOrosz; Gábor eOrosz; Dávid eFarkas; Dávid eFarkas; Dávid eFarkas; Christine eRoland-Levy

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast,...

Comparison of exit time moment spectra for extrinsic metric balls

DEFF Research Database (Denmark)

Hurtado, Ana; Markvorsen, Steen; Palmer, Vicente

2012-01-01

We prove explicit upper and lower bounds for the $L^1$-moment spectra for the Brownian motion exit time from extrinsic metric balls of submanifolds $P^m$ in ambient Riemannian spaces $N^n$. We assume that $P$ and $N$ both have controlled radial curvatures (mean curvature and sectional curvature...... obtain new intrinsic comparison results for the exit time spectra for metric balls in the ambient manifolds $N^n$ themselves....

Further Examining the American Dream: Differential Correlates of Intrinsic and Extrinsic Goals.

Science.gov (United States)

Kasser, Tim; Ryan, Richard M.

1996-01-01

In a sample of adult subjects (Study One), the relative importance and efficacy of extrinsic aspirations for financial success, an appealing appearance, and social recognition were associated with lower vitality and self-actualization and more physical symptoms. Study Two replicated these findings in a sample of college students. (JPS)

Restorative Management of Intrinsic and Extrinsic Dental Erosion.

Science.gov (United States)

Al-Salehi, Samira Kathryn

2014-12-01

The restorative management of tooth surface loss is highlighted through the presentation of two advanced cases of dental erosion. On presentation, the causes of the dental erosion in both patients had been previously diagnosed and stopped. The first patient was a 67 year old with intrinsic erosion and an element of attrition where a multidisciplinary approach was used. The other, a 17 year old patient with extrinsic erosion managed via adhesive restorations. Adhesive techniques are a relatively simple, effective and conservative method for the treatment of dental erosion. The two treatment modalities (conventional versus contemporary) are compared and discussed.

The Effect of Toughening Combined with Microjet Cooling During Quenching (Solution Heat Treatment of Calcium Carbide-Modified CuAl10Fe4Ni4 Alloy on its Mechanical Properties

Directory of Open Access Journals (Sweden)

Górny Z.

2013-03-01

Full Text Available The work presents the results of the experimental research concerning the impact of a heat treatment (toughening of aluminum bronze CuAl10Fe4Ni4 on its mechanical properties. The conditions of the experiments and selected results are described. A detailed description of the effects of individual heat treatment conditions namely low and high temperature aging is also presented in the work.

The Effect of Toughening Combined with Microjet Cooling During Quenching (Solution Heat Treatment of Calcium Carbide-modified CuAl10Fe4Ni4 Alloy on its Mechanical Properties

Directory of Open Access Journals (Sweden)

Z. Górny

2013-01-01

Full Text Available The work presents the results of the experimental research concerning the impact of a heat treatment (toughening of aluminum bronze CuAl10Fe4Ni4 on its mechanical properties. The conditions of the experiments and selected results are described. A detailed description of the effects of individual heat treatment conditions namely low and high temperature aging is also presented in the work.

Maximum toe flexor muscle strength and quantitative analysis of human plantar intrinsic and extrinsic muscles by a magnetic resonance imaging technique.

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Kurihara, Toshiyuki; Yamauchi, Junichiro; Otsuka, Mitsuo; Tottori, Nobuaki; Hashimoto, Takeshi; Isaka, Tadao

2014-01-01

The aims of this study were to investigate the relationships between the maximum isometric toe flexor muscle strength (TFS) and cross-sectional area (CSA) of the plantar intrinsic and extrinsic muscles and to identify the major determinant of maximum TFS among CSA of the plantar intrinsic and extrinsic muscles. Twenty six young healthy participants (14 men, 12 women; age, 20.4 ± 1.6 years) volunteered for the study. TFS was measured by a specific designed dynamometer, and CSA of plantar intrinsic and extrinsic muscles were measured using magnetic resonance imaging (MRI). To measure TFS, seated participants optimally gripped the bar with their toes and exerted maximum force on the dynamometer. For each participant, the highest force produced among three trials was used for further analysis. To measure CSA, serial T1-weighted images were acquired. TFS was significantly correlated with CSA of the plantar intrinsic and extrinsic muscles. Stepwise multiple linear regression analyses identified that the major determinant of TFS was CSA of medial parts of plantar intrinsic muscles (flexor hallucis brevis, flexor digitorum brevis, quadratus plantae, lumbricals and abductor hallucis). There was no significant difference between men and women in TFS/CSA. CSA of the plantar intrinsic and extrinsic muscles is one of important factors for determining the maximum TFS in humans.

Fabrication of SiC Composites with Synergistic Toughening of Carbon Whisker and In Situ 3C-SiC Nanowire

Directory of Open Access Journals (Sweden)

Zhang Yunlong

2016-01-01

Full Text Available The SiC composites with synergistic toughening of carbon whisker and in situ 3C-SiC nanowire have been fabricated by hot press sinter technology and annealed treatment technology. Effect of annealed time on the morphology of SiC nanowires and mechanical properties of the Cw/SiC composites was surveyed in detail. The appropriate annealed time improved mechanical properties of the Cw/SiC composites. The synergistic effect of carbon whisker and SiC nanowire can improve the fracture toughness for Cw/SiC composites. The vapor-liquid-solid growth (VLS mechanism was proposed. TEM photo showed that 3C-SiC nanowire can be obtained with preferential growth plane ({111}, which corresponded to interplanar spacing about 0.25 nm.

Associations among teacher-student interpersonal relationships and students’ intrinsic and extrinsic motivation and academic achievement: A cross cultural study

OpenAIRE

Chan, Dawn

2016-01-01

This cross-cultural study explored associations among teacher-student relationship, students’ intrinsic and extrinsic motivation, and students’ academic achievement in grade 5 and 6 students from Vancouver, Canada (n = 102) and Hong Kong, China (n = 207). Hong Kong students perceived their teachers to be more dissatisfied, strict, admonishing, and uncertain, while Vancouver students perceived their teachers to be more helpful and friendly. Students’ levels of intrinsic and extrinsic motivatio...

Intrinsic and Extrinsic Motivation: Evaluating Benefits and Drawbacks from College Instructors' Perspectives

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Lei, Simon A.

2010-01-01

A growing body of literature has been examined and discussed the effects of intrinsic and extrinsic motivation on student learning at the college level. Intrinsically motivated individuals have been able to develop high regards for learning various types of course information without the inclusion of external rewards or reinforcements. In…

Intrinsic and Extrinsic Regulation of PD-L2 Expression in Oncogene-Driven Non-Small Cell Lung Cancer.

Science.gov (United States)

Shibahara, Daisuke; Tanaka, Kentaro; Iwama, Eiji; Kubo, Naoki; Ota, Keiichi; Azuma, Koichi; Harada, Taishi; Fujita, Jiro; Nakanishi, Yoichi; Okamoto, Isamu

2018-03-27

The interaction of programmed cell death ligand 2 (PD-L2) with programmed cell death 1 is implicated in tumor immune escape. The regulation of PD-L2 expression in tumor cells has remained unclear, however. We here examined intrinsic and extrinsic regulation of PD-L2 expression in NSCLC. PD-L2 expression was evaluated by reverse transcription and real-time polymerase chain reaction analysis and by flow cytometry. BEAS-2B cells stably expressing an activated mutant form of EGFR or the echinoderm microtubule associated protein like 4 (EML4)-ALK receptor tyrosine kinase fusion oncoprotein manifested increased expression of PD-L2 at both the mRNA and protein levels. Furthermore, treatment of NSCLC cell lines that harbor such driver oncogenes with corresponding EGFR or ALK tyrosine kinase inhibitors or depletion of EGFR or ALK by small interfering RNA transfection suppressed expression of PD-L2, demonstrating that activating EGFR mutations or echinoderm microtubule associated protein like 4 gene (EML4)-ALK receptor tyrosine kinase gene (ALK) fusion intrinsically induce PD-L2 expression. We also found that interferon gamma (IFN-γ) extrinsically induced expression of PD-L2 through signal transducer and activator of transcription 1 signaling in NSCLC cells. Oncogene-driven expression of PD-L2 in NSCLC cells was inhibited by knockdown of the transcription factors signal transducer and activator of transcription 3 (STAT3) or c-FOS. IFN-γ also activated STAT3 and c-FOS, suggesting that these proteins may also contribute to the extrinsic induction of PD-L2 expression. Expression of PD-L2 is induced intrinsically by activating EGFR mutations or EML4-ALK fusion and extrinsically by IFN-γ, with STAT3 and c-FOS possibly contributing to both intrinsic and extrinsic pathways. Our results thus provide insight into the complexity of tumor immune escape in NSCLC. Copyright © 2018 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

The impact of intrinsic and extrinsic factors on the job satisfaction of dentists.

Science.gov (United States)

Goetz, K; Campbell, S M; Broge, B; Dörfer, C E; Brodowski, M; Szecsenyi, J

2012-10-01

The Two-Factor Theory of job satisfaction distinguishes between intrinsic-motivation (i.e. recognition, responsibility) and extrinsic-hygiene (i.e. job security, salary, working conditions) factors. The presence of intrinsic-motivation facilitates higher satisfaction and performance, whereas the absences of extrinsic factors help mitigate against dissatisfaction. The consideration of these factors and their impact on dentists' job satisfaction is essential for the recruitment and retention of dentists. The objective of the study is to assess the level of job satisfaction of German dentists and the factors that are associated with it. This cross-sectional study was based on a job satisfaction survey. Data were collected from 147 dentists working in 106 dental practices. Job satisfaction was measured with the 10-item Warr-Cook-Wall job satisfaction scale. Organizational characteristics were measured with two items. Linear regression analyses were performed in which each of the nine items of the job satisfaction scale (excluding overall satisfaction) were handled as dependent variables. A stepwise linear regression analysis was performed with overall job satisfaction as the dependent outcome variable, the nine items of job satisfaction and the two items of organizational characteristics controlled for age and gender as predictors. The response rate was 95.0%. Dentists were satisfied with 'freedom of working method' and mostly dissatisfied with their 'income'. Both variables are extrinsic factors. The regression analyses identified five items that were significantly associated with each item of the job satisfaction scale: 'age', 'mean weekly working time', 'period in the practice', 'number of dentist's assistant' and 'working atmosphere'. Within the stepwise linear regression analysis the intrinsic factor 'opportunity to use abilities' (β = 0.687) showed the highest score of explained variance (R(2) = 0.468) regarding overall job satisfaction. With respect to the Two

Extrinsic rewards undermine altruistic tendencies in 20-month-olds.

Science.gov (United States)

Warneken, Felix; Tomasello, Michael

2008-11-01

The current study investigated the influence of rewards on very young children's helping behavior. After 20-month-old infants received a material reward during a treatment phase, they subsequently were less likely to engage in further helping during a test phase as compared with infants who had previously received social praise or no reward at all. This so-called overjustification effect suggests that even the earliest helping behaviors of young children are intrinsically motivated and that socialization practices involving extrinsic rewards can undermine this tendency.

Intrinsic and Extrinsic Motivation, Orientation and Achievements in L2 of Arab Learners of English, French and German: A Study from Jordan

Science.gov (United States)

Kreishan, Lana J.; Al-Dhaimat, Yahya

2013-01-01

The aim of this research is to explore Jordanian undergraduate students' intrinsic and extrinsic motivations and instrumental and integrative orientations toward learning English, French, and German as foreign languages. The paper also reflects on how subtypes of intrinsic and extrinsic motivations relate to orientations and examines possible…

The extrinsic affective Simon task as an instrument for indirect assessment of prejudice

NARCIS (Netherlands)

Degner, J.; Wentura, D.

2008-01-01

We report one study that explored the applicability of the Extrinsic Affective Simon Task (EAST) as an indirect measure of prejudice. The EAST detected known differences in reactions revealing that a Turkish outgroup was spontaneously evaluated more negatively than the German ingroup. More

The fragmented self : imbalance between intrinsic and extrinsic self-networks in psychotic disorders

NARCIS (Netherlands)

Ebisch, Sjoerd J. H.; Aleman, Andre

Self-disturbances are among the core features of schizophrenia and related psychotic disorders. The basic structure of the self could depend on the balance between intrinsic and extrinsic self-processing. We discuss studies on self-related processing in psychotic disorders that provide converging

Are Competition and Extrinsic Motivation Reliable Predictors of Academic Cheating?

OpenAIRE

Orosz, G?bor; Farkas, D?vid; Roland-L?vy, Christine

2013-01-01

Previous studies suggest that extrinsic motivation and competition are reliable predictors of academic cheating. The aim of the present questionnaire study was to separate the effects of motivation- and competition-related variables on academic cheating by Hungarian high school students (N = 620, M = 264, F = 356). Structural equation modeling showed that intrinsic motivation has a negative effect, and amotivation has a positive indirect effect on self-reported academic cheating. In contrast,...

Obesity and Cancer Metabolism: A Perspective on Interacting Tumor-Intrinsic and Extrinsic Factors.

Science.gov (United States)

Doerstling, Steven S; O'Flanagan, Ciara H; Hursting, Stephen D

2017-01-01

Obesity is associated with increased risk and poor prognosis of many types of cancers. Several obesity-related host factors involved in systemic metabolism can influence tumor initiation, progression, and/or response to therapy, and these have been implicated as key contributors to the complex effects of obesity on cancer incidence and outcomes. Such host factors include systemic metabolic regulators including insulin, insulin-like growth factor 1, adipokines, inflammation-related molecules, and steroid hormones, as well as the cellular and structural components of the tumor microenvironment, particularly adipose tissue. These secreted and structural host factors are extrinsic to, and interact with, the intrinsic metabolic characteristics of cancer cells to influence their growth and spread. This review will focus on the interplay of these tumor cell-intrinsic and extrinsic factors in the context of energy balance, with the objective of identifying new intervention targets for preventing obesity-associated cancer.

Effects of intra- and inter-laminar resin content on the mechanical properties of toughened composite materials

Science.gov (United States)

Grande, Dodd H.; Ilcewicz, Larry B.; Avery, William B.; Bascom, Willard D.

1991-01-01

Composite materials having multiphase toughened matrix systems and laminate architectures characterized by resin-rich interlaminar layers (RIL) have been the subject of much recent attention. Such materials are likely to find applications in thick compressively loaded structures such as the keel area of commercial aircraft fuselages. The effects of resin content and its interlaminar and intralaminar distribution on mechanical properties were investigated with test and analysis of two carbon-epoxy systems. The RIL was found to reduce the in situ strengthening effect for matrix cracking in laminates. Mode 2 fracture toughness was found to increase with increasing RIL thickness over the range investigated, and Mode 1 interlaminar toughness was negligibly affected. Compressive failure strains were found to increase with increasing resin content for specimens having no damage, holes, and impact damage. Analytical tools for predicting matrix cracking of off-axis plies and damage tolerance in compression after impact (CAI) were successfully applied to materials with RIL.

Reasons for quitting: intrinsic and extrinsic motivation for smoking cessation in a population-based sample of smokers.

Science.gov (United States)

Curry, S J; Grothaus, L; McBride, C

1997-01-01

An intrinsic-extrinsic model of motivation for smoking cessation is extended to a population-based sample of smokers (N = 1,137), using a previously validated Reasons for Quitting (RFQ) scale. Psychometric evaluation of the RFQ replicated the model that includes health concerns and self-control as intrinsic motivation dimensions and immediate reinforcement and social influence as extrinsic motivation dimensions. Compared to volunteers, the population-based sample of smokers reported equivalent health concerns, lower self-control, and higher social influence motivation for cessation. Within the population-based sample, women compared to men were less motivated to quit by health concerns and more motivated by immediate reinforcement; smokers above age 55 expressed lower health concerns and higher self-control motivation than smokers below age 55. Higher baseline levels of intrinsic relative to extrinsic motivation were associated with more advanced stages of readiness to quit smoking and successful smoking cessation at a 12-month follow-up. Among continuing smokers, improvement in stage of readiness to quit over time was associated with significant increases in health concerns and self-control motivation.

Geomorphology of Dra Abu el-Naga (Egypt): The basis of the funerary sacred landscape

Science.gov (United States)

Bardají, T.; Martínez-Graña, A.; Sánchez-Moral, S.; Pethen, H.; García-González, D.; Cuezva, S.; Cañaveras, J. C.; Jiménez-Higueras, A.

2017-07-01

A geological and geomorphological analysis has been performed in the necropolis of Dra Abu el-Naga in order to understand the role played by these two factors in the development of the sacred landscape. The investigation focuses upon two aspects of the development of the necropolis, the selection criteria for tomb location and the reconstruction of the ancient funerary landscape. Around 50 tombs were surveyed, analysing the characteristics of their host rock and classifying them according to a modified Rock Mass Rating Index, in order to understand how rock quality affected tomb construction. This analysis resulted in the definition of five rock-quality classes (I to V) from very good to very poor rock. The geological study also resulted in a proposed geological-geomorphological model for the evolution of this zone of the Theban necropolis that complements previous works by other authors. Due to the lack of precise dating evidence this chronology is a relative one and is based on the chronology given by other authors for similar deposits and events. Two catastrophic events, represented by mega-landslides, have been identified, the first one predates the deposition of early Pleistocene fluvial deposits, and the second one possibly occurred during the middle-late Pleistocene. Two weathering surfaces developed under wetter than present climatic conditions and have been tentatively correlated to the mid-late Pleistocene humid period and the African-Humid Period (early-mid Holocene).

Urinary sugars biomarker relates better to extrinsic than to intrinsic sugars intake in a metabolic study with volunteers consuming their normal diet.

Science.gov (United States)

Tasevska, N; Runswick, S A; Welch, A A; McTaggart, A; Bingham, S A

2009-05-01

Sugars in diet are very difficult to measure because of the unreliability of self-reported dietary intake. Sucrose and fructose excreted in urine have been recently suggested as a biomarker for total sugars intake. To further characterize the use of this biomarker, we investigated whether urinary sugars correlated better to extrinsic compared to intrinsic sugars in the diet. Seven male and six female healthy participants were living for 30 days in a metabolic suite under strictly controlled conditions consuming their usual diet as assessed beforehand from four consecutive 7-day food diaries kept at home. During the 30-day study, all 24 h urine specimens were collected, validated for their completeness and analysed for sucrose and fructose. The mean total sugars intake in the group was 202+/-69 g day(-1). Daily intake of extrinsic, intrinsic and milk sugars contributed 60.1, 34.4 and 5.5%, to the total sugars intake, respectively. The individuals' 30-day mean sugars excretion levels were significantly correlated with the 30-day means of extrinsic sugars (r=0.84; Psugars intake (r=0.43; P=0.144). In the regression, only extrinsic sugars intake explained a significant proportion of the variability in sugars excretion (adjusted R(2)=0.64; P=0.001); daily excretion of 100 mg sucrose and fructose in urine predicted 124 g of extrinsic total sugars in the diet. Using fewer urinary and dietary measurements in the analysis did not change the overall trend of the findings. In this group of volunteers, sucrose and fructose in urine better correlated to extrinsic than to intrinsic sugars intake.

Estimating intrinsic and extrinsic noise from single-cell gene expression measurements

Science.gov (United States)

Fu, Audrey Qiuyan; Pachter, Lior

2017-01-01

Gene expression is stochastic and displays variation (“noise”) both within and between cells. Intracellular (intrinsic) variance can be distinguished from extracellular (extrinsic) variance by applying the law of total variance to data from two-reporter assays that probe expression of identically regulated gene pairs in single cells. We examine established formulas [Elowitz, M. B., A. J. Levine, E. D. Siggia and P. S. Swain (2002): “Stochastic gene expression in a single cell,” Science, 297, 1183–1186.] for the estimation of intrinsic and extrinsic noise and provide interpretations of them in terms of a hierarchical model. This allows us to derive alternative estimators that minimize bias or mean squared error. We provide a geometric interpretation of these results that clarifies the interpretation in [Elowitz, M. B., A. J. Levine, E. D. Siggia and P. S. Swain (2002): “Stochastic gene expression in a single cell,” Science, 297, 1183–1186.]. We also demonstrate through simulation and re-analysis of published data that the distribution assumptions underlying the hierarchical model have to be satisfied for the estimators to produce sensible results, which highlights the importance of normalization. PMID:27875323

Proprioceptive bimanual test in intrinsic and extrinsic coordinates.

Science.gov (United States)

Iandolo, Riccardo; Squeri, Valentina; De Santis, Dalia; Giannoni, Psiche; Morasso, Pietro; Casadio, Maura

2015-01-01

Is there any difference between matching the position of the hands by asking the subjects to move them to the same spatial location or to mirror-symmetric locations with respect to the body midline? If the motion of the hands were planned in the extrinsic space, the mirror-symmetric task would imply an additional challenge, because we would need to flip the coordinates of the target on the other side of the workspace. Conversely, if the planning were done in intrinsic coordinates, in order to move both hands to the same spot in the workspace, we should compute different joint angles for each arm. Even if both representations were available to the subjects, the two tasks might lead to different results, providing some cue on the organization of the "body schema". In order to answer such questions, the middle fingertip of the non-dominant hand of a population of healthy subjects was passively moved by a manipulandum to 20 different target locations. Subjects matched these positions with the middle fingertip of their dominant hand. For most subjects, the matching accuracy was higher in the extrinsic modality both in terms of systematic error and variability, even for the target locations in which the configuration of the arms was the same for both modalities. This suggests that the matching performance of the subjects could be determined not only by proprioceptive information but also by the cognitive representation of the task: expressing the goal as reaching for the physical location of the hand in space is apparently more effective than requiring to match the proprioceptive representation of joint angles.

Rigid particle revisited: Extrinsic curvature yields the Dirac equation

Energy Technology Data Exchange (ETDEWEB)

Deriglazov, Alexei, E-mail: alexei.deriglazov@ufjf.edu.br [Depto. de Matemática, ICE, Universidade Federal de Juiz de Fora, MG (Brazil); Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30 (Russian Federation); Nersessian, Armen, E-mail: arnerses@ysu.am [Yerevan State University, 1 Alex Manoogian St., Yerevan 0025 (Armenia); Laboratory of Mathematical Physics, Tomsk Polytechnic University, 634050 Tomsk, Lenin Ave. 30 (Russian Federation)

2014-03-01

We reexamine the model of relativistic particle with higher-derivative linear term on the first extrinsic curvature (rigidity). The passage from classical to quantum theory requires a number of rather unexpected steps which we report here. We found that, contrary to common opinion, quantization of the model in terms of so(3.2)-algebra yields massive Dirac equation. -- Highlights: •New way of canonical quantization of relativistic rigid particle is proposed. •Quantization made in terms of so(3.2) angular momentum algebra. •Quantization yields massive Dirac equation.

Older adults' intrinsic and extrinsic motivation toward physical activity.

Science.gov (United States)

Dacey, Marie; Baltzell, Amy; Zaichkowsky, Len

2008-01-01

To examine how motives discriminate 3 physical activity levels of inactive, active, and sustained maintainers. Six hundred forty-five adults (M age = 63.8) completed stage-of-change and Exercise Motivations Inventory (EMI-2) scales. Exploratory factor analysis established psychometric properties of the EMI-2 suitable for older adults. Six factors emerged in the EMI-2: health and fitness, social/emotional benefits, weight management, stress management, enjoyment, and appearance. Enjoyment contributed most to differentiating activity levels. Moderators of age and gender were delineated. Intrinsic motivation and self-determined extrinsic motivation distinguish older adults' activity levels.

Nanocellulose composites with enhanced interfacial compatibility and mechanical properties using a hybrid-toughened epoxy matrix.

Science.gov (United States)

Kuo, Pei-Yu; Barros, Luizmar de Assis; Yan, Ning; Sain, Mohini; Qing, Yan; Wu, Yiqiang

2017-12-01

Although there is a growing interest in utilizing nanocellulose fibres (NCFs) based composites for achieving a higher sustainability, mechanical performance of these composites is limited due to the poor compatibility between fibre reinforcement and polymer matrices. Here we developed a bio-nanocomposite with an enhanced fibre/resin interface using a hybrid-toughened epoxy. A strong reinforcing effect of NCFs was achieved, demonstrating an increase up to 88% in tensile strength and 298% in tensile modulus as compared to neat petro-based P-epoxy. The toughness of neat P-epoxy was improved by 84% with the addition of 10wt% bio-based E-epoxy monomers, which also mitigated the amount of usage of bisphenol A (BPA). The morphological analyses showed that the hybrid epoxy improved the resin penetration and fibre distribution significantly in the resulting composites. Thus, our findings demonstrated the promise of developing sustainable and high performance epoxy composites combing NCFs with a hybrid petro-based and bio-based epoxy resin system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identity Processes and Intrinsic and Extrinsic Goal Pursuits: Directionality of Effects in College Students.

Science.gov (United States)

Luyckx, Koen; Duriez, Bart; Green, Lindsey M; Negru-Subtirica, Oana

2017-08-01

Identity research has mainly focused on the degree to which adolescents and emerging adults engage in exploration and commitment to identity goals and strivings. Somewhat lacking from this research tradition is an explicit focus on the content of the identity goals that individuals deem important and pursue. The present manuscript describes two longitudinal studies sampling college students in which we examine how exploration and commitment processes relate to intrinsic and extrinsic goal pursuits as defined in Self-Determination Theory. Study 1 was a two-wave longitudinal study spanning 6 months (N = 370; 77.4% women; mean age 18.24 years); Study 2 was a three-wave longitudinal study spanning 6 months (N = 458 students; 84.9% women; mean age 18.25 years). Using cross-lagged path analyses, hypotheses were supported to various degrees of convergence between studies, pointing to the extent of which results were replicated across our two independent longitudinal samples. Whereas an intrinsic goal orientation positively predicted commitment making (Study 1) and identification with commitment over time (Studies 1 and 2), an extrinsic goal orientation positively predicted ruminative exploration over time, which led to decreases in intrinsic orientation over time (Study 2). Further, an intrinsic goal orientation negatively predicted ruminative exploration over time (Study 1). The findings in for pro-active exploration processes were inconsistent across both studies, being prospectively related to both intrinsic (Study 2) and extrinsic goal orientations (Study 1). Implications and suggestions for future research are discussed.

Microstructural characterization of a zirconia-toughened alumina fiber reinforced niobium aluminide composite

International Nuclear Information System (INIS)

Nourbakhsh, S.; Sahin, O.; Rhee, W.H.; Margolin, H.

1992-01-01

This paper reports on an NbAl 3 + Nb 2 Al composite reinforced with continuous zirconia-toughened alumina, PRD-166 fibers, that was produced by pressure casing and was examined by optical and transmission electron microscopy and energy dispersive spectroscopy. Exposure of the fiber to the molten metal resulted in ZrO 2 and Al; 2 O 3 grain growth, formation of a thin layer of an amorphous phase on the grain boundaries of Al 2 O 3 and transformation of ZrO 2 . Preferential Al 2 O 3 grain growth near the surface of the fiber led to the rejection of ZrO 2 from this region into the molten metal. In NbAl 3 slip occurred by the glide of a left-angle 110 right-angle superdislocations and to a lesser extent by the glide of a pair of left-angle 11 bar 1 right-angle + left-angle 3 bar 1 bar 1 right-angle dislocations on the (112) planes and a/2 left-angle 110 right-angle superpartial dislocations on the (001) plane. The operating slip system in Nb 2 Al was identified as {010 left-angle 100 right-angle. A left-angle 100 right-angle dislocations were dissociated into a/x left-angle 100 right-angle partial dislocations joined together by a stacking fault

Intrinsic and Extrinsic Reading Motivation as Predictors of Reading Literacy: A Longitudinal Study

Science.gov (United States)

Becker, Michael; McElvany, Nele; Kortenbruck, Marthe

2010-01-01

The purpose in this study was to examine the longitudinal relationships of intrinsic and extrinsic motivation with reading literacy development. In particular, the authors (a) investigated reading amount as mediator between motivation and reading literacy and (b) probed for bidirectional relationships between reading motivation and reading…

European Educational Research Quality Indicators (EERQI): A first prototype framework of intrinsic and extrinsic indicators

NARCIS (Netherlands)

Mooij, Ton

2011-01-01

Mooij, T. (2011, 15-16 March). European Educational Research Quality Indicators (EERQI): A first prototype framework of intrinsic and extrinsic indicators. Paper presented at the final EERQI conference, Brussels, University Foundation.

Geometric size effect on the extrinsic Gilbert damping in laterally confined magnetic structures

Energy Technology Data Exchange (ETDEWEB)

Song, Hyon-Seok [Department of Emerging Materials Science, DGIST, Daegu 42988 (Korea, Republic of); Lee, Kyeong-Dong [Department of Materials Science and Engineering, KAIST, Daejeon 34141 (Korea, Republic of); You, Chun-Yeol [Department of Physics, Inha University, Incheon 22212 (Korea, Republic of); Park, Byong-Guk [Department of Materials Science and Engineering, KAIST, Daejeon 34141 (Korea, Republic of); Hong, Jung-Il, E-mail: jihong@dgist.ac.kr [Department of Emerging Materials Science, DGIST, Daegu 42988 (Korea, Republic of); Research Centre for Emerging Materials, DGIST, Daegu 42988 (Korea, Republic of)

2016-05-15

We investigated spin dynamics in micron-length scale patterned thin films using the GPU-based micromagnetic simulation program. Spin precessional motion was induced by a Gaussian-pulse magnetic field. The effective Gilbert damping was examined by tracking the precessional motion of the spins, and we found that the damping constant depends on the size and shape of the pattern as well as the externally applied magnetic field. Additional extrinsic damping generated around the edge region was attributed to the dephasing effect between the fundamental spin wave and other spin wave modes. We find that the effect of extrinsic damping could be eliminated by proper adjustments of sample size, external bias field, position, and area of observation. - Highlights: • GPU based micromagnetic simulation of spin dynamics in the micropatterned ferromagnetic films. • Effect of edge regions of the pattern on the Gilbert damping behaviors. • Guide for the analyses of intrinsic magnetic damping in the micron scale patterned films.

Prevalence and Extrinsic Risk Factors for Dental Erosion in Adolescents.

Science.gov (United States)

Mafla, Ana C; Cerón-Bastidas, Ximena A; Munoz-Ceballos, Maria E; Vallejo-Bravo, Diana C; Fajardo-Santacruz, Maria C

This manuscript examined the prevalence and extrinsic risk factors for dental erosion (DE) in early and middle adolescents in Pasto, Colombia. Dental erosion was evaluated in a random sample of 384 individuals aged 10-15 years attending three primary and high schools in this cross-sectional study. Clinical dental assessment for DE was done using O'Sullivan index. Data on general sociodemographic variables and extrinsic risks factors were obtained. Descriptive and univariate binary logistic regression analyses were performed. Dental erosion was observed in 57.3% of individuals. The univariate binary logistic regression analysis showed that frequency of drinking natural fruit juices (OR 2.670, 95% CI 1.346 - 5.295, P=0.004) and their pH (OR 2.303, 95% CI 1.292 - 4.107, P=0.004) were more associated with the odd of DE in early adolescence. However, a high SES (OR 10.360, 95% CI 3.700 - 29.010, P<0.001) and frequency of snacks with artificial lemon taste (OR 3.659, 95% CI 1.506 - 8.891, P=0.003) were highly associated with the risk of DE in middle adolescence. The results suggest that DE is a prevalent condition in adolescents living in a city in southern Colombia. The transition from early to middle adolescence implies new bio-psychosocial changes, which increase the risk for DE.

Extrinsic stretching narrowing and anterior indentation of the rectosigmoid junction

International Nuclear Information System (INIS)

Schulman, A.; Fataar, S.

1979-01-01

Thirty-five cases of extrinsic narrowing or anterior indentation of the rectosigmoid junction (RSJ) have been studied. The RSJ lies directly behind the pouch of Douglas which is a favoured site for peritoneal metastasis, abscess and endometriosis. Any space-occupying lesion of sufficient size at this site will indent the anterior aspects of the RSJ. Causes include distension or tumour of the ileum or sigmoid colon, gross ascites (when the patient is erect), and tumours below the pelvic peritonium, such as gynaecological neoplasm and internal iliac artery aneurysm. When a desmoplastic metastasis in the pouch of Douglas infiltrates the outer layers of the RSJ, the fibrosis produces an eccentric shortening on its anterior aspect, which in turn causes a pleating of the mucosa with the folds radiating towards the shortened area. This is also seen with primary pelvic carcinomas directly adherent to the rectum, endometriosis with repeated bleeding and increasing eccentric, submucosal fibrosis, and chronic abscess in the pouch of Douglas. Not all extrinsic narrowing of the RSJ are pathological. One case of anterior indentation followed operation for rectal prolapse. Ten additional cases showed narrowing due to a technical artefact air-distended colon rising into the upper abdomen to cause stretching at the RSJ. As with ascites, this narrowing due to 'high-rise sigmoid' disappeared when the patients became recumbent and the colonic air redistributed. (author)

Perceived influence of intrinsic/extrinsic factors on participation in life activities after spinal cord injury.

Science.gov (United States)

Cobb, John E; Leblond, Jean; Dumont, Frédéric S; Noreau, Luc

2018-04-03

Various types of limitations on community participation are experienced by people with spinal cord injury (SCI). To determine: 1) the perceived influence of six intrinsic/extrinsic factors (i.e. physical impairment, emotional condition, thinking skills, environment, lack of assistance, discrimination) on participation in 26 life activities, 2) if this influence varied based on extent of participation, and 3) if personal or environmental characteristics influenced perceptions. Secondary analysis of a cohort (SCI Community Survey, n = 1508) using the SCI Person-Perceived Participation in Daily Activities Questionnaire. Frequency tables, Fisher's exact tests and correspondence analyses. Respectively, 79.6% and 38.5% of respondents perceived that their physical impairment and the natural and/or built environment were the main factors that limited participation across all activities. Considering participation between three groups (no participation; less than wanted; as much as wanted), significant differences (p intrinsic/extrinsic factors on participation was not significantly influenced by other personal or environmental characteristics. A majority of people with SCI perceived that their participation is limited by one or more of intrinsic/extrinsic factors. Perceptions regarding which factors influence participation differ between activities and these perceptions appear related to the extent of participation suggesting that those who actively participate could be the most sensitive to limitations in certain activities. Copyright © 2018 Elsevier Inc. All rights reserved.

Mapping the coupled role of structure and materials in mechanics of platelet-matrix composites

Science.gov (United States)

Farzanian, Shafee; Shahsavari, Rouzbeh

2018-03-01

Despite significant progresses on understanding and mimicking the delicate nano/microstructure of biomaterials such as nacre, decoding the indistinguishable merger of materials and structures in controlling the tradeoff in mechanical properties has been long an engineering pursuit. Herein, we focus on an archetype platelet-matrix composite and perform ∼400 nonlinear finite element simulations to decode the complex interplay between various structural features and material characteristics in conferring the balance of mechanical properties. We study various combinatorial models expressed by four key dimensionless parameters, i.e. characteristic platelet length, matrix plasticity, platelet dissimilarity, and overlap offset, whose effects are all condensed in a new unifying parameter, defined as the multiplication of strength, toughness, and stiffness over composite volume. This parameter, which maximizes at a critical characteristic length, controls the transition from intrinsic toughening (matrix plasticity driven without crack growths) to extrinsic toughening phenomena involving progressive crack propagations. This finding, combined with various abstract volumetric and radar plots, will not only shed light on decoupling the complex role of structure and materials on mechanical performance and their trends, but provides important guidelines for designing lightweight staggered platelet-matrix composites while ensuring the best (balance) of their mechanical properties.

Tensile behaviour of drawn tungsten wire used in tungsten fibre-reinforced tungsten composites

International Nuclear Information System (INIS)

Riesch, J; Feichtmayer, A; Fuhr, M; Gietl, H; Höschen, T; Neu, R; Almanstötter, J; Coenen, J W; Linsmeier, Ch

2017-01-01

In tungsten fibre-reinforced tungsten composites (W f /W) the brittleness problem of tungsten is solved by utilizing extrinsic toughening mechanisms. The properties of the composite are very much related to the properties of the drawn tungsten wire used as fibre reinforcements. Its high strength and capability of ductile deformation are ideal properties facilitating toughening of W f /W. Tensile tests have been used for determining mechanical properties and study the deformation and the fracture behaviour of the wire. Tests of as-fabricated and straightened drawn wires with a diameter between 16 and 150 μ m as well as wire electrochemically thinned to a diameter of 5 μ m have been performed. Engineering stress–strain curves and a microscopic analysis are presented with the focus on the ultimate strength. All fibres show a comparable stress–strain behaviour comprising necking followed by a ductile fracture. A reduction of the diameter by drawing leads to an increase of strength up to 4500 MPa as a consequence of a grain boundary hardening mechanism. Heat treatment during straightening decreases the strength whereas electrochemical thinning has no significant impact on the mechanical behaviour. (paper)

Comparison of intrinsic and extrinsic tracer methods for estimating calcium bioavailability to rats from dairy foods

International Nuclear Information System (INIS)

Buchowski, M.S.; Sowizral, K.C.; Lengemann, F.W.; Van Campen, D.; Miller, D.D.

1989-01-01

Dairy products doubly labeled with 45Ca and 47Ca were used to evaluate an extrinsic labeling procedure for calcium bioavailability determination. Nonfat milk, yogurt, and fresh cheese curd were prepared from caprine milk that was intrinsically labeled with 45Ca. The products were then labeled extrinsically with 47Ca and administered to rats by gavage. The 47Ca to 45Ca ratio in bone and teeth averaged about 1.00 with either milk, yogurt, or CaCl2, but the ratio was about 1.04 when dosed with cheese curd. Ca absorption, determined by whole-body counting of 47Ca, was lower (P less than 0.05) in cheese curd (59%) than in either milk (69%), yogurt (72%), or CaCl2 (72%). Expressed as percent of dose, the absorption of 47Ca was highly correlated with bone 47Ca (r = 0.973) and with bone 45Ca (r = 0.946). Correlation between tibia 47Ca and tibia 45Ca was r = 0.923. For the dairy products tested, our results indicated that extrinsic 47Ca was absorbed similarly to intrinsic 45Ca. Moreover, the percent of radioactive dose retained in bone appears to be a valid indicator of relative bioavailability of food Ca

Extrinsic pseudocapacitve Li-ion storage of SnS anode via lithiation-induced structural optimization on cycling

Science.gov (United States)

Lian, Qingwang; Zhou, Gang; Liu, Jiatu; Wu, Chen; Wei, Weifeng; Chen, Libao; Li, Chengchao

2017-10-01

Here, we report a new enhanced extrinsic pseudocapacitve Li-ion storage mechanism via lithiation-induced structural optimization strategy. The flower-like C@SnS and bulk SnS exhibit initial capacity decay and subsequent increase of capacity on cycling. After a long-term lithiation/delithiation process, flower-like C@SnS and bulk SnS exhibit improved rate performance and reversible capacity in comparison with those of initial state. Moreover, a high capacity of 530 mAh g-1 is still remained even after 1550 cycles at a high current density of 5.0 A g-1 for flower-like C@SnS after pre-lithiation of 350 cycles. According to the comprehensive analysis of structural evolution and electrochemical performance, it demonstrates that SnS electrodes experience crystal size reduction and further amorphization on cycling, which enhances the reversibility of conversion reaction for SnS, leading to increasing capacity. On the other hand, surface-dominated extrinsic pseudocapacitive contribution results in enhanced rate performance because electrodes expose a large fraction of Li+ sites on surface or near-surface region with structural optimization on cycling. This study reveals that extrinsic pseudocapacitance of SnS can be stimulated via lithiation-induced structural optimization, which gives rise to high-rate and long-lived performances.

Let's stay together? Intrinsic and extrinsic factors involved in pair bond dissolution in a recolonizing wolf population.

Science.gov (United States)

Milleret, Cyril; Wabakken, Petter; Liberg, Olof; Åkesson, Mikael; Flagstad, Øystein; Andreassen, Harry Peter; Sand, Håkan

2017-01-01

For socially monogamous species, breeder bond dissolution has important consequences for population dynamics, but the extent to which extrinsic or intrinsic population factors causes pair dissolution remain poorly understood, especially among carnivores. Using an extensive life-history data set, a survival analysis and competing risks framework, we examined the fate of 153 different wolf (Canis lupus) pairs in the recolonizing Scandinavian wolf population, during 14 winters of snow tracking and DNA monitoring. Wolf pair dissolution was generally linked to a mortality event and was strongly affected by extrinsic (i.e. anthropogenic) causes. No divorce was observed, and among the pair dissolution where causes have been identified, death of one or both wolves was always involved. Median time from pair formation to pair dissolution was three consecutive winters (i.e. approximately 2 years). Pair dissolution was mostly human-related, primarily caused by legal control actions (36·7%), verified poaching (9·2%) and traffic-related causes (2·1%). Intrinsic factors, such as disease and age, accounted for only 7·7% of pair dissolutions. The remaining 44·3% of dissolution events were from unknown causes, but we argue that a large portion could be explained by an additional source of human-caused mortality, cryptic poaching. Extrinsic population factors, such as variables describing the geographical location of the pair, had a stronger effect on risk of pair dissolution compared to anthropogenic landscape characteristics. Population intrinsic factors, such as the inbreeding coefficient of the male pair member, had a negative effect on pair bond duration. The mechanism behind this result remains unknown, but might be explained by lower survival of inbred males or more complex inbreeding effects mediated by behaviour. Our study provides quantitative estimates of breeder bond duration in a social carnivore and highlights the effect of extrinsic (i.e. anthropogenic) and

Metacognitive Monitoring and Dementia: How Intrinsic and Extrinsic Cues Influence Judgments of Learning in People with Alzheimer’s disease

Science.gov (United States)

Thomas, Ayanna K.; Lee, Meeyeon; Balota, David A.

2014-01-01

Objective The present research compared metamemorial monitoring processes among younger adults, non-demented older adults, and older adults diagnosed with early stage Dementia of the Alzheimer’s Type (DAT). Method In three experiments we examined the influence of intrinsic and extrinsic cues on Judgment of Learning (JOL) accuracy. Changes in association strength between cue-target word pairs served as our intrinsic manipulation in Experiments 1 and 2. Changes in encoding orientation served as our extrinsic manipulation in Experiment 3. Results Across all experiments we found that young adults, non-demented older adults, and individuals in the early stages of DAT effectively used intrinsic and extrinsic factors to guide JOL predictions. Conclusions We conclude that while certain aspects of metacognition may be impaired in both the normal and demented older populations, these groups remain able to use theory-based processing, or general knowledge about how memory works, to make metamemory monitoring predictions. PMID:23876118

The linear interplay of intrinsic and extrinsic noises ensures a high accuracy of cell fate selection in budding yeast

Science.gov (United States)

Li, Yongkai; Yi, Ming; Zou, Xiufen

2014-01-01

To gain insights into the mechanisms of cell fate decision in a noisy environment, the effects of intrinsic and extrinsic noises on cell fate are explored at the single cell level. Specifically, we theoretically define the impulse of Cln1/2 as an indication of cell fates. The strong dependence between the impulse of Cln1/2 and cell fates is exhibited. Based on the simulation results, we illustrate that increasing intrinsic fluctuations causes the parallel shift of the separation ratio of Whi5P but that increasing extrinsic fluctuations leads to the mixture of different cell fates. Our quantitative study also suggests that the strengths of intrinsic and extrinsic noises around an approximate linear model can ensure a high accuracy of cell fate selection. Furthermore, this study demonstrates that the selection of cell fates is an entropy-decreasing process. In addition, we reveal that cell fates are significantly correlated with the range of entropy decreases. PMID:25042292

Adaptive influence of extrinsic and intrinsic factors on variation of incubation periods among tropical and temperate passerines

Science.gov (United States)

Martin, Thomas E.; Ton, Riccardo; Oteyza, Juan C.

2018-01-01

Understanding intrinsic (physiological) and extrinsic (e.g., temperature) causes of variation in embryonic development time (incubation period) is important because they can have different impacts on individual quality. Robert Ricklefs and colleagues have argued that longer incubation periods result primarily from intrinsic physiological programs that increase individual quality and adult survival. They claim that incubation periods are largely invariant and that extrinsic factors like temperature have little impact. We have argued that adult survival may be a cause rather than a consequence of much of the variation in embryonic development time. A reduction in extrinsic sources of annual adult mortality (e.g., migration, predation, nonbreeding-season mortality) favors reduced parental effort during incubation to minimize costs to future reproduction and survival. Reduced parental effort, in turn, manifests as cooler average egg temperatures that yield longer incubation periods. Ricklefs and colleagues mischaracterized our hypothesis and deconstructed their own incorrect version, while also making some incorrect statements. We show that reevaluation of previous evidence provided by this group actually supports a role of egg temperature for the variation in incubation periods. We also summarize other observational and experimental evidence that incubation periods are not invariant and that egg temperature has a strong causal influence on variation within and among species. In fact, egg temperature explains ∼60% of the difference in incubation periods among species. The remaining ∼40% reflects intrinsic physiological programs and other factors, potentially providing intrinsic benefits. Ultimately, annual adult mortality explains substantial variation in parental effort and egg temperature, and the latter strongly explains variation in incubation periods. Both intrinsic programs and extrinsic temperature effects need to be considered in attempts to understand

Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple

International Nuclear Information System (INIS)

Gitto, Salvatore; Messina, Carmelo; Mauri, Giovanni; Aliprandi, Alberto; Sardanelli, Francesco; Sconfienza, Luca Maria

2017-01-01

Highlights: • US allows for rapid, cost-effective, and non-invasive assessment of wrist ligaments. • Knowledge of landmarks and dynamic manoeuvres is basic for a systematic examination. • A sequential approach is effective, timesaving and feasible in clinical practice. - Abstract: Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique.

Predicting the effect of extrinsic and intrinsic job satisfaction factors on recruitment and retention of rehabilitation professionals.

Science.gov (United States)

Randolph, Diane Smith

2005-01-01

The purpose of this study was to ascertain which extrinsic and intrinsic job satisfaction areas are most predictive of rehabilitation professionals' career satisfaction and desire to stay on the job. This article discusses the results of a survey conducted on practicing occupational therapists, physical therapists, and speech-language pathologists regarding factors that contribute to career satisfaction and desire to stay on the job. Five hundred surveys were mailed to each profession; 463 were returned, of which 328 were able to be analyzed. Results from regression analysis showed that intrinsic factors such as professional growth and having a work environment in line with personal values are more significant in predicting career satisfaction than are extrinsic factors such as pay and continuing education. These same intrinsic factors are also significant in predicting the rehabilitation professional's desire to stay on the job. These findings are significant to healthcare managers desiring to recruit and retain qualified occupational therapists, physical therapists, and speech-language pathologists. In addition to extrinsic benefits such as pay, healthcare managers need to focus on provision of intrinsic factors such as opportunities for professional growth, recognition of accomplishments, and opportunities for departmental input to motivate rehabilitation professionals.

Dynamic high-resolution ultrasound of intrinsic and extrinsic ligaments of the wrist: How to make it simple

Energy Technology Data Exchange (ETDEWEB)

Gitto, Salvatore, E-mail: sal.gitto@gmail.com [Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milano (Italy); Messina, Carmelo [Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milano (Italy); Mauri, Giovanni [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Dipartimento di Radiologia Interventistica, Istituto Europeo di Oncologia, Via Ripamonti 435, 20141 Milano (Italy); Aliprandi, Alberto [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Sardanelli, Francesco [Servizio di Radiologia, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese (Italy); Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Pascal 36, 20133 Milano (Italy); Sconfienza, Luca Maria [Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Via Pascal 36, 20133 Milano (Italy); Unità Operativa di Radiologia/Diagnostica per Immagini con Servizio di Radiologia Interventistica, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161 Milano (Italy)

2017-02-15

Highlights: • US allows for rapid, cost-effective, and non-invasive assessment of wrist ligaments. • Knowledge of landmarks and dynamic manoeuvres is basic for a systematic examination. • A sequential approach is effective, timesaving and feasible in clinical practice. - Abstract: Wrist ligaments are crucial structures for the maintenance of carpal stability. They are classified into extrinsic ligaments, connecting the carpus with the forearm bones or distal radioulnar ligaments, and intrinsic ligaments, entirely situated within the carpus. Lesions of intrinsic and extrinsic ligaments of the wrist have been demonstrated to occur largely, mostly in patients with history of trauma and carpal instability, or rheumatoid arthritis. Ultrasound allows for rapid, cost-effective, non-invasive and dynamic evaluation of the wrist, and may represent a valuable diagnostic tool. Although promising results have been published, ultrasound of wrist ligaments is not performed in routine clinical practice, maybe due to its technical feasibility regarded as quite complex. This review article aims to enlighten readers about the normal sonographic appearance of intrinsic and extrinsic carpal ligaments, and describe a systematic approach for their sonographic assessment with detailed anatomic landmarks, dynamic manoeuvres and scanning technique.

Estimating consumer preferences for extrinsic and intrinsic attributes of vegetables. A study of German consumers

Energy Technology Data Exchange (ETDEWEB)

Jimenez-Guerrero, J. F.; Gazquez-Abad, J. C.; Huertas-Garcia, R.; Mondejar-Jimenez, J. A.

2012-11-01

Preference formation developed during the consumers evaluation of alternatives is one of the most important stages in models of consumer purchasing behaviour. This is especially true for the purchase of vegetables. The purpose of this paper is to analyze the role of extrinsic versus intrinsic attributes in the behaviour of consumer when purchasing cucumbers, considering four attributes; price, country of origin and production method (extrinsic), and freshness (intrinsic). Utilizing a sample of German tourists visiting the city of Almeria (Spain), conjoint analysis methodology is used. The results suggest that an intrinsic aspect (freshness) is the most important attribute for consumers. Therefore, marketers are advised to consider the importance of this attribute to the consumer and try to position the product in the destination markets on the basis of product freshness. (Author) 91 refs.

ESTIMATION OF INTRINSIC AND EXTRINSIC ENVIRONMENT FACTORS OF AGE-RELATED TOOTH COLOUR CHANGES

Czech Academy of Sciences Publication Activity Database

Hyšpler, P.; Jezbera, D.; Fürst, T.; Mikšík, Ivan; Waclawek, M.

2010-01-01

Roč. 17, č. 4 (2010), s. 515-525 ISSN 1898-6196 Institutional research plan: CEZ:AV0Z50110509 Keywords : age-related colour changes of teeth * intrinsic and extrinsic factors * 3D mathematical regression models * estimation of real age Subject RIV: ED - Physiology Impact factor: 0.294, year: 2010

On the comparison of the ballistic performance of 10% zirconia toughened alumina and 95% alumina ceramic target

International Nuclear Information System (INIS)

Zhang, X.F.; Li, Y.C.

2010-01-01

Ballistic performance of different type of ceramic materials subjected to high velocity impact was investigated in many theoretical, experimental and numerical studies. In this study, a comparison of ballistic performance of 95% alumina ceramic and 10% zirconia toughened alumina (ZTA) ceramic tiles was analyzed theoretically and experimentally. Spherical cavity model based on the concepts of mechanics of compressible porous media of Galanov was used to analyze the relation of target resistance and static mechanical properties. Experimental studies were carried out on the ballistic performance of above two types of ceramic tiles based on the depth of penetration (DOP) method, when subjected to normal impact of tungsten long rod projectiles. Typical damaged targets were presented. The residual depth of penetration on after-effect target was measured in all experiments, and the ballistic efficiency factor of above two types ceramic plates were determined. Both theoretical and experimental results show that the improvement on ballistic resistance was clearly observed by increasing fracture toughness in ZTA ceramics.

Examining the relationship between recreational sport participation and intrinsic and extrinsic motivation and amotivation.

Science.gov (United States)

Tsorbatzoudis, Haralambos; Alexandris, Konstantinos; Zahariadis, Panagiotis; Grouios, George

2006-10-01

This study aimed at investigating the effect of motivational dimensions proposed by Pelletier, et al. in 1995, both on sport participation levels and on intention for continuing participation among adult recreational sport participants. Two hundred and fifty-seven adult individuals, who reported participation in some type of sport and physical activity, completed the Sport Motivation Scale and a scale measuring intention. The study provided evidence to suggest that increased motivation leads to increased participation. Amotivation significantly decreased from the least to the most frequent participant groups, while both extrinsic and intrinsic motivation followed the reverse pattern. The results also indicated that increased intrinsic motivation to gain knowledge and accomplishment and extrinsic motivation (introjected regulation) are positively correlated with individuals' intentions to continue participation, while amotivation is negatively related. These results provide limited support for the self-determination theory. Implications for sport participation promotion are discussed.

Efficient simulation of intrinsic, extrinsic and external noise in biochemical systems

Science.gov (United States)

Pischel, Dennis; Sundmacher, Kai; Flassig, Robert J.

2017-01-01

Abstract Motivation: Biological cells operate in a noisy regime influenced by intrinsic, extrinsic and external noise, which leads to large differences of individual cell states. Stochastic effects must be taken into account to characterize biochemical kinetics accurately. Since the exact solution of the chemical master equation, which governs the underlying stochastic process, cannot be derived for most biochemical systems, approximate methods are used to obtain a solution. Results: In this study, a method to efficiently simulate the various sources of noise simultaneously is proposed and benchmarked on several examples. The method relies on the combination of the sigma point approach to describe extrinsic and external variability and the τ-leaping algorithm to account for the stochasticity due to probabilistic reactions. The comparison of our method to extensive Monte Carlo calculations demonstrates an immense computational advantage while losing an acceptable amount of accuracy. Additionally, the application to parameter optimization problems in stochastic biochemical reaction networks is shown, which is rarely applied due to its huge computational burden. To give further insight, a MATLAB script is provided including the proposed method applied to a simple toy example of gene expression. Availability and implementation: MATLAB code is available at Bioinformatics online. Contact: flassig@mpi-magdeburg.mpg.de Supplementary information: Supplementary data are available at Bioinformatics online. PMID:28881987

The gut microbiome restores intrinsic and extrinsic nerve function in germ-free mice accompanied by changes in calbindin.

Science.gov (United States)

McVey Neufeld, K A; Perez-Burgos, A; Mao, Y K; Bienenstock, J; Kunze, W A

2015-05-01

The microbiome is essential for normal myenteric intrinsic primary afferent neuron (IPAN) excitability. These neurons control gut motility and modulate gut-brain signaling by exciting extrinsic afferent fibers innervating the enteric nervous system via an IPAN to extrinsic fiber sensory synapse. We investigated effects of germ-free (GF) status and conventionalization on extrinsic sensory fiber discharge in the mesenteric nerve bundle and IPAN electrophysiology, and compared these findings with those from specific pathogen-free (SPF) mice. As we have previously shown that the IPAN calcium-dependent slow afterhyperpolarization (sAHP) is enhanced in GF mice, we also examined the expression of the calcium-binding protein calbindin in these neurons in these different animal groups. IPAN sAHP and mesenteric nerve multiunit discharge were recorded using ex vivo jejunal gut segments from SPF, GF, or conventionalized (CONV) mice. IPANs were excited by adding 5 μM TRAM-34 to the serosal superfusate. We probed for calbindin expression using immunohistochemical techniques. SPF mice had a 21% increase in mesenteric nerve multiunit firing rate and CONV mice a 41% increase when IPANs were excited by TRAM-34. For GF mice, this increase was barely detectable (2%). TRAM-34 changed sAHP area under the curve by -77 for SPF, +3 for GF, or -54% for CONV animals. Calbindin-immunopositive neurons per myenteric ganglion were 36% in SPF, 24% in GF, and 52% in CONV animals. The intact microbiome is essential for normal intrinsic and extrinsic nerve function and gut-brain signaling. © 2015 John Wiley & Sons Ltd.

Electrophysiological and histological changes in extrinsic muscles proximal to post burn contractures of hand.

Science.gov (United States)

Bhattacharya, V; Purwar, Shammi; Joshi, D; Kumar, M; Mandal, S; Chaudhuri, G R; Bhattacharya, S

2011-06-01

Burn scar hand contractures of variable degree are frequently encountered. Although the forearm is apparently spared, it was clinically observed that there was disuse atrophy in the unburnt extrinsic forearm muscles. Usually the clinicians do not give much importance to this fact. The girth at the midforearm was significantly reduced as compared to normal side. The flexion of the hand joints are governed by two components (a) intrinsic and (b) extrinsic muscles. The intrinsic muscles are directly involved in the contracted tissue. Therefore it was thought essential to evaluate the extrinsic group of muscles for their contribution in the final functional recovery following corrective surgery. Thirty patients having unilateral post thermal burn contracture sparing forearm were studied. A detailed clinical evaluation was made including grade of contracture and reduction in the forearm girth. The forearm unburnt muscles were evaluated by preoperative electrophysiological studies. Intraoperative biopsies were taken from these muscles for histopathological examination. On histopathological examination, there were significant abnormal changes in the form of muscle fiber atrophy, fibrolipomatous tissue replacement of atrophic muscle fibers and sarcolemmal changes. These changes were directly proportional to the severity of contractures. The electrophysiological studies showed proportionate changes in the form of reduction in amplitude, duration and interference. This study suggests that if these changes are mild and in reversible stage, they will favourably affect the functional recovery following surgery. However if these changes are of severe grade and irreversible, in spite of adequate surgery, splinting and physiotherapy, the functional recovery may not be complete. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.

Characterising Extrinsic Challenges Linked to the Design and Implementation of Inquiry-Based Practical Work

Science.gov (United States)

Akuma, Fru Vitalis; Callaghan, Ronel

2017-11-01

Inquiry-based science education has been incorporated in science curricula internationally. In this regard, however, many teachers encounter challenges. The challenges have been characterised into those linked to the personal characteristics of these teachers (intrinsic challenges) and others associated with contextual factors (extrinsic challenges). However, this level of characterisation is inadequate in terms of appreciating the complexity of the challenges, tracking of their development, and discovering knowledge within specific categories. Against this background, the purpose of the research presented here was to characterise extrinsic challenges linked to the design and implementation of inquiry-based practical work. In order to do so, we used a conceptual framework of teaching challenges based on Bronfenbrenner's ecological theory of human development. The data gathered using a multi-method case study of practical work in two South African high schools, was analysed by combining the data-driven inductive approach and the deductive a priori template of codes approach in thematic analysis. On this basis, the extrinsic challenges linked to the design and implementation of inquiry-based practical work that participants are confronted with, were found to consist of macrosystem challenges (such as a restrictive curriculum) and microsystem challenges. At the latter level, the challenges are material-related (e.g., lack of science education equipment and materials) or non-material-related (such as time constraints and the lack of access to interactive computer simulations). We have discussed the theory-, practice- and research-based implications of these results in relation to the design and implementation of inquiry-based practical work in South Africa and internationally.

Tensile fracture and thermal conductivity characterization of toughened epoxy/CNT nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Balakrishnan, Anandh [School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019 (United States); Saha, Mrinal C., E-mail: msaha@ou.edu [School of Aerospace and Mechanical Engineering, University of Oklahoma, Norman, OK 73019 (United States)

2011-01-25

Rubber toughened epoxy/CNT nanocomposites were manufactured at different weight percents between 0 and 1% of multiwall carbon nanotube (MWNT) using a high intensity ultrasonic liquid processor with a titanium probe. Mechanical properties of manufactured dog bone samples were measured in tension and the results indicated a maximum of 23% increase in the elastic modulus at 0.6% by weight of MWNT. However, the fracture strength showed a maximum decrease of about 11% as a function of increasing MWNT loading. Scanning Electron Microscopy (SEM) images from the neat samples revealed a distinct circular pit at the top left edge of the specimen with an overall tearing deformation causing the fracture paths. Comparatively, all nanocomposite samples on an average seemed to show a prominent brittle fracture with little or no evidence of circular pit formation. The amount of tearing deformation seemed to be enhanced in the nanocomposite specimens as compare to the neat ones. Finally, Transmission Electron Microscopy images indicated that different states of dispersion exist in all of the nanocomposite samples. The data showed that agglomeration of nanotubes increases as a function of weight percent. In addition to mechanical property characterization, thermal conductivity of all the samples was determined as a function of temperature between 30 deg. C and 100 deg. C using the 3{omega} method. The tested samples showed an almost 16% increase in thermal conductivity. The minimal enhancement in thermal conductivity has been analyzed from the standpoint of the Effective Medium Theory. Interfacial thermal resistances exhibit no order of magnitude changes explaining the conductivity results.

Tensile fracture and thermal conductivity characterization of toughened epoxy/CNT nanocomposites

International Nuclear Information System (INIS)

Balakrishnan, Anandh; Saha, Mrinal C.

2011-01-01

Rubber toughened epoxy/CNT nanocomposites were manufactured at different weight percents between 0 and 1% of multiwall carbon nanotube (MWNT) using a high intensity ultrasonic liquid processor with a titanium probe. Mechanical properties of manufactured dog bone samples were measured in tension and the results indicated a maximum of 23% increase in the elastic modulus at 0.6% by weight of MWNT. However, the fracture strength showed a maximum decrease of about 11% as a function of increasing MWNT loading. Scanning Electron Microscopy (SEM) images from the neat samples revealed a distinct circular pit at the top left edge of the specimen with an overall tearing deformation causing the fracture paths. Comparatively, all nanocomposite samples on an average seemed to show a prominent brittle fracture with little or no evidence of circular pit formation. The amount of tearing deformation seemed to be enhanced in the nanocomposite specimens as compare to the neat ones. Finally, Transmission Electron Microscopy images indicated that different states of dispersion exist in all of the nanocomposite samples. The data showed that agglomeration of nanotubes increases as a function of weight percent. In addition to mechanical property characterization, thermal conductivity of all the samples was determined as a function of temperature between 30 deg. C and 100 deg. C using the 3ω method. The tested samples showed an almost 16% increase in thermal conductivity. The minimal enhancement in thermal conductivity has been analyzed from the standpoint of the Effective Medium Theory. Interfacial thermal resistances exhibit no order of magnitude changes explaining the conductivity results.

Students' Extrinsic and Intrinsic Motivation Level and Its Relationship with Their Mathematics Achievement

Science.gov (United States)

Acar Güvendir, Meltem

2016-01-01

This study focused on the extrinsic and intrinsic motivation levels of eighth grade students and its relationship with their mathematical achievement. The participants of the study included 6,829 students who took TIMSS in 2011 and 239 mathematics teachers. The data obtained from the student and teacher questionnaires that are included in the…

Bioavailability of iron to rats from processed soybean fractions determined by intrinsic and extrinsic labeling techniques

International Nuclear Information System (INIS)

Weaver, C.M.; Nelson, N.; Elliott, J.G.

1984-01-01

Intrinsic and extrinsic labeling techniques were used to measure iron bioavailability from soybean fractions (isolated soy protein, defatted flour, soy hulls, insoluble material and whey) by iron-depleted and non-iron-depleted rats. As expected, absorption of iron was higher in the iron-depleted than in the non-iron-depleted rats. In the iron-depleted group, significantly more iron was absorbed from soy whey than from other fractions. No other significant difference in iron absorption associated with iron source was observed. The higher absorption rate of iron from whey by the iron-depleted rats probably was related to a lower quantity of food consumed during the test meal by this group. Intrinsic and extrinsic labeling techniques produced similar assessments of bioavailability of iron

Validation of the design of small diameter pulsed columns for the process line DRA. Tests reliability compared with the industrial scale

International Nuclear Information System (INIS)

Leybros, J.

2000-01-01

As part of the Spin program related to the management of nuclear wastes, studies have been undertaken to develop partitioning processes like Diamex process. The process line CCBP/DRA in Atalante facility forms one of the main equipment devoted to these studies. On this line industrial apparatus are used but some like pulsed columns need to be adapted because of the specificity of the installation: limiting amount of nuclear matter, gaseous waste minimization, safety, limiting amounts of new extractants,... This article presents the comparison of 2 air pulsed columns, one with a standard diameter of 25 (DN25), the other with a reduced diameter of 15 (DN15). This comparison is based on 3 main criteria: pulsation capability, superficial throughput and mass transfer efficiency. The overall comparison shows that a DN15 pulsed column can be considered as a representative tool of research and development. Particularly, the study demonstrates the possibility of scaling up the results

Editorial "Homenaje a una de nuestras más destacadas colaboradoras, la Dra. Ninoska Maneiro Malavé".

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Ivan Santelices Malfanti

2011-04-01

Full Text Available En esta edición de la Revista Ingeniería Industrial sentimos el deber de hacer un paréntesis: rendir un merecido homenaje a una de nuestras más destacadas colaboradoras, la Dra. Ninoska Maneiro Malavé, profesora de la Universidad de Carabobo, Venezuela, recientemente fallecida. La doctora Maneiro, miembro de nuestro Comité Editor, compartió  muchas experiencias con nosotros, demostrando siempre un gran amor por la ciencia, por la investigación y la divulgación de ésta. Cuando hablaba de la revista se refería a ella como si se tratara de su propio hogar, de su familia. Decía sentirnos como sus propios amigos, y veía en esta publicación una parte de su propia patria afectiva. Así la recuerdan hoy sus amigos y colegas. Así la recordamos nosotros: como una gran profesional y, sobre todo, como un gran ser humano. La revista Ingeniería Industrial, en nombre de la ciencia, en nombre de la investigación, y en nombre de todos quienes la hacemos, expresa el más profundo sentimiento de pesar por su ausencia repentina.

Intrinsic and Extrinsic Contributions to Seated Balance in the Sagittal and Coronal Planes: Implications for Trunk Control After Spinal Cord Injury.

Science.gov (United States)

Audu, Musa L; Triolo, Ronald J

2015-08-01

The contributions of intrinsic (passive) and extrinsic (active) properties of the human trunk, in terms of the simultaneous actions about the hip and spinal joints, to the control of sagittal and coronal seated balance were examined. Able-bodied (ABD) and spinal-cord-injured (SCI) volunteers sat on a moving platform which underwent small amplitude perturbations in the anterior-posterior (AP) and medial-lateral (ML) directions while changes to trunk orientation were measured. A linear parametric model that related platform movement to trunk angle was fit to the experimental data by identifying model parameters in the time domain. The results showed that spinal cord injury leads to a systematic reduction in the extrinsic characteristics, while most of the intrinsic characteristics were rarely affected. In both SCI and ABD individuals, passive characteristics alone were not enough to maintain seated balance. Passive stiffness in the ML direction was almost 3 times that in the AP direction, making more extrinsic mechanisms necessary for balance in the latter direction. Proportional and derivative terms of the extrinsic model made the largest contribution to the overall output from the active system, implying that a simple proportional plus derivative (PD) controller structure will suffice for restoring seated balance after spinal cord injury.

MR imaging of normal extrinsic wrist ligaments using thin slices with clinical and surgical correlation

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Shahabpour, M., E-mail: maryam.shahabpour@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); De Maeseneer, M., E-mail: michel.demaeseneer@uzbrussel.be [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Pouders, C. [Department of Experimental Anatomy, Vrije Universiteit Brussel (Belgium); Van Overstraeten, L. [Department of Foot and Hand Surgery, Centre Hospitalier Regional de Wallonie Picarde, Tournai (Belgium); Ceuterick, P. [Department of Hand Surgery, Europa Ziekenhuizen, Brussels (Belgium); Fierens, Y. [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium); Goubau, J. [Department of Orthopaedic Surgery, UZ Brussel, Brussels (Belgium); De Mey, J. [Department of Radiology, Universitair Ziekenhuis Brussel, Brussels (Belgium)

2011-02-15

Eighty-nine MR examinations of the wrist were retrospectively analyzed. MRI results were compared with clinical findings and/or arthroscopy. Thin proton density and T2 weighted sequences and 3D DESS weighted sequences were applied on a 1.5 T scanner. On the palmar side three radiocarpal ligaments are recognized including the radioscaphocapitate, radiolunotriquetral, radioscapholunate, and midcarpal triquetroscaphoidal ligaments. Ulnocarpal ligaments include the ulnolunate ligament and the ulnotriquetral ligament. On the dorsal side three ligaments are recognized: the dorsal radiolunotriquetral, and the midcarpal triquetroscaphoidal and triquetro-trapezoido-trapezial. The collateral ligaments include the radial and ulnar collateral ligament. MR is a valuable technique in the assessment of the extrinsic and midcarpal ligaments. Depiction of the extrinsic ligaments can best be accomplished with coronal 3D DESS sequences and sagittal and transverse proton density and T2 weighted sequences with thin slices.

Intrinsic Motivation, Extrinsic Motivation, and Academic Achievement among Indian Adolescents in Canada and India

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Areepattamannil, Shaljan; Freeman, John G.; Klinger, Don A.

2011-01-01

The purpose of the present study was to examine the relationships among intrinsic motivation, extrinsic motivation, and academic achievement for the Indian immigrant adolescents in Canada in comparison to their counterparts in India. Descriptive discriminant analysis indicated that the Indian immigrant adolescents in Canada had higher intrinsic…

An Exploratory Study of Intrinsic & Extrinsic Motivators and Student Performance in an Auditing Course

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Mo, Songtao

2011-01-01

The objective of this study is to investigate the association of intrinsic and extrinsic motivators and student performance. This study performs an exploratory analysis and presents evidence to demonstrate that intrinsic motivators affect the connection between external motivators and student performance. The empirical tests follow the framework…

Sesamol induced apoptotic effect in lung adenocarcinoma cells through both intrinsic and extrinsic pathways.

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Siriwarin, Boondaree; Weerapreeyakul, Natthida

2016-07-25

Sesamol is a phenolic lignan found in sesame seeds (Sesamum indicum L.) and sesame oil. The anticancer effects and molecular mechanisms underlying its apoptosis-inducing effect were investigated in human lung adenocarcinoma (SK-LU-1) cells. Sesamol inhibited SK-LU-1 cell growth with an IC50 value of 2.7 mM and exhibited less toxicity toward normal Vero cells after 48 h of treatment (Selective index = 3). Apoptotic bodies-the hallmark of apoptosis-were observed in sesamol-treated SK-LU-1 cells, stained with DAPI. Sesamol increased the activity of caspase 8, 9, and 3/7, indicating that apoptotic cell death occurred through both extrinsic and intrinsic pathways. Sesamol caused the loss of mitochondrial transmembrane potential signifying intrinsic apoptosis induction. Decreasing Bid expression revealed crosstalk between the intrinsic and extrinsic apoptotic pathways; demonstrating clearly that sesamol induces apoptosis through both pathways in human lung adenocarcinoma (SK-LU-1) cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Both Intrinsic and Extrinsic Religious Orientation are Positively Associated with Attitudes Toward Cleanliness: Exploring Multiple Routes from Godliness to Cleanliness.

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Litman, Leib; Robinson, Jonathan; Weinberger-Litman, Sarah L; Finkelstein, Ron

2017-08-24

In the present study, we explore how intrinsic and extrinsic religious orientations are associated with cleanliness attitudes. We find that reported importance of religion is associated with increased cleanliness concerns and interest in cleanliness. Attitudes toward cleanliness were also associated with both intrinsic religious orientation and extrinsic religious orientation. Together, religiosity and religious orientation account for 14.7% of cleanliness attitudes and remained significant in the presence of personality, socioeconomic status, age, education, obsessive-compulsive attitudes toward cleanliness, and other covariates. These results show that religiosity is associated with cleanliness via multiple routes. We suggest that intrinsic religious orientation leads to increased interest in cleanliness due to the link between physical and spiritual purity. Extrinsic religious orientation may be linked with cleanliness because of the secondary benefits, including health and the facilitation in communal cohesiveness, that cleanliness rituals offer. The implications of these findings for the relationship between religion and health are discussed.

Extrinsic and intrinsic blood supply to the optic chiasm.

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Salaud, Céline; Ploteau, Stéphane; Blery, Pauline; Pilet, Paul; Armstrong, Olivier; Hamel, Antoine

2018-04-01

Although there have been many studies of the arterial cerebral blood supply, only seven have described the optic chiasm (OC) blood supply and their results are contradictory. The aim of this study was to analyze the extrinsic and intrinsic OC blood supply on cadaveric specimens using dissections and microcomputer tomography (Micro-CT). Thirteen human specimens were dissected and the internal or common carotid arteries were injected with red latex, China Ink with gelatin or barium sulfate. Three Micro-CTs were obtained to reveal the intrinsic blood supply to the OC. The superior hypophyseal arteries (SupHypA) (13/13) and posterior communicating artery (PCoA) (12/13) supplied the pial network on the inferior side of the OC. The first segment of the anterior cerebral artery (ACA) (10/10), SupHypA (7/10), the anterior communicating artery (ACoA) (9/10), and PComA (1/10) supplied the pial network of its superior side. The intrinsic OC blood supply was divided into three networks (two lateral and one central). Capillaries entering the OC originated principally from the inferior pial network. The lateral network capillaries had the same orientation as the visual lateral pathways, but the central network was not correlated with the nasal fibers crossing into the OC. There was no anastomosis in the pial or intrinsic networks. Only SupHypA, PCoA, ACoA, and ACA were involved in the OC blood supply. Because there was no extrinsic or intrinsic anastomosis, all arteries should be preserved. Tumor compression of the inferior intrinsic arterial network could contribute to visual defects. Clin. Anat. 31:432-440, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

A dynamic traction splint for the management of extrinsic tendon tightness.

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Dovelle, S; Heeter, P K; Phillips, P D

1987-02-01

The dynamic traction splint designed by therapists at Walter Reed Army Medical Center is used for the management of extrinsic extensor tendon tightness commonly seen in brachial plexus injuries and traumatic soft tissue injuries of the upper extremity. The two components of the splint allow for simultaneous maximum flexion of the MCP and IP joints. This simple and economical splint provides an additional modality to any occupational therapy service involved in the management of upper extremity disorders.

Zirconia toughened alumina ceramic foams for potential bone graft applications: fabrication, bioactivation, and cellular responses.

Science.gov (United States)

He, X; Zhang, Y Z; Mansell, J P; Su, B

2008-07-01

Zirconia toughened alumina (ZTA) has been regarded as the next generation orthopedic graft material due to its excellent mechanical properties and biocompatibility. Porous ZTA ceramics with good interconnectivity can potentially be used as bone grafts for load-bearing applications. In this work, three-dimensional (3D) interconnected porous ZTA ceramics were fabricated using a direct foaming method with egg white protein as binder and foaming agent. The results showed that the porous ZTA ceramics possessed a bimodal pore size distribution. Their mechanical properties were comparable to those of cancellous bone. Due to the bio-inertness of alumina and zirconia ceramics, surface bioactivation of the ZTA foams was carried out in order to improve their bioactivity. A simple NaOH soaking method was employed to change the surface chemistry of ZTA through hydroxylation. Treated samples were tested by conducting osteoblast-like cell culture in vitro. Improvement on cells response was observed and the strength of porous ZTA has not been deteriorated after the NaOH treatment. The porous 'bioactivated' ZTA ceramics produced here could be potentially used as non-degradable bone grafts for load-bearing applications.

Tangible and Intangible Rewards and Employee Creativity: The Mediating Role of Situational Extrinsic Motivation

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Yoon, Hye Jung; Sung, Sun Young; Choi, Jin Nam; Lee, Kyungmook; Kim, Seongsu

2015-01-01

This study examined the effects of tangible and intangible forms of creativity-contingent rewards on employee creativity. Situation-specific intrinsic and extrinsic motivations were proposed as mediators of the reward-creativity link. Based on data collected from 271 employees and their supervisors, results revealed the following: (a) intangible…

The efficacy of two prototype chewing gums for the removal of extrinsic tooth stain

NARCIS (Netherlands)

Ozcan, M; Kulak, Y; Kazazoglu, E

Aim: To compare the potential efficacy of two prototype chewing gums in extrinsic stain removal on natural teeth. Setting: Dental school clinics. Design: Double-blind, two groups, parallel design. Participants: 76 adult volunteers (32m, 44f, mean age: 20.6 years old). Methods: Oral hard and soft

The string model with the extrinsic curvature term

International Nuclear Information System (INIS)

Itoi, C.; Kubota, Hiroshi

1988-01-01

The string model with the extrinsic curvature is studied which is a gauge invariant field theory with higher order derivatives. We present an equivalent action without any higher order derivatives which keeps the gauge invariance. We point out the difficulty caused by the second class constraints in Dirac's canonical method. Following a new method for dynamical systems with second class constraints, we construct a equivalent model which has no second class constraints but has a new gauge invariance. This gauge invariance guarantees the equivalence between the original model and new one. We show that the model can be quantized in this formalism. In a simple model, we show the nilpotence of the BRST charge under certain conditions, and discuss the unitarity of the theory. (author)

“Las crónicas indígenas y mestizas son el ‘espejo’ –a veces cóncavo– de un arduo proceso de recreación y transformación literarias ocurrido en Hispanoamérica”. Entrevista a la Dra. Raquel Chang-Rodríguez

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Ena Mercedes Matienzo León

2014-06-01

Full Text Available Entrevista a la Dra. Raquel Chang-Rodríguez, Distinguished Professor de Literatura y Cultura Hispánicas en The Graduate Center y en The City College de The City University of New York (CUNY, en torno a su especialidad, los estudios coloniales hispanoamericanos.

Theory of extrinsic and intrinsic heterojunctions in thermal equilibrium

Science.gov (United States)

Von Ross, O.

1980-01-01

A careful analysis of an abrupt heterojunction consisting of two distinct semiconductors either intrinsic or extrinsic is presented. The calculations apply to a one-dimensional, nondegenerate structure. Taking into account all appropriate boundary conditions, it is shown that the intrinsic Fermi level shows a discontinuity at the interface between the two materials which leads to a discontinuity of the valence band edge equal to the difference in the band gap energies of the two materials. The conduction band edge stays continuous however. This result is independent of possible charged interface states and in sharp contrast to the Anderson model. The reasons for this discrepancy are discussed.

Perceptions of intrinsically and extrinsically motivated distance education students of the barriers to persistence

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G. P. Fourie

1998-06-01

Full Text Available The aim of the study was to investigate the influence of intrinsic and extrinsic motivation on the perceptions held by distance education students of the barriers to persistence. A review of the literature on attrition in traditional and distance education and motivation to learn in adults - with specific reference to intrinsic and extrinsic motivation, as well as barriers to persistence - is presented. The "Barriers to Persistence Questionnaire" (BPQ, consisting of 97 items, was developed. It was administered, in combination with Maritz's (1980 86 item "Motivation to Learn Questionnaire" (MLQ to 212 adults enrolled for management development programmes via distance education. Statistically significant differences were found between predominantly intrinsically motivated students and those students who were predominantly extrinsically motivated. The implications of the findings/ as well as the implications for distance education institutions and organisations involved in distance education, are discussed. Opsomming Die doel van die studie was om die invloed van intrinsieke en ekstrinsieke motivering op die persepsies van afstandsonderrigstudente van die hindemisse tot volharding te ondersoek. 'n Literatuuroorsig ten opsigte van slytasie in tradisionele onderrig en afstandsonderrig, asook die rol van motivering in volwasse onderrig - met spesifieke verwysing na intrinsieke en ekstrinsieke motivering, asook die hindemisse tot volharding - is gedoen. Die "Barriers to Persistence Questionnaire" (BPQ is ontwikkel, bestaande uit 97 items. Dit is saam met Maritz (1980 se 86- item "Motivation to Learn Questionnaire" toegepas op 212 volwassenes wat geregistreer is vir bestuursontwikkelingsprogramme via afstandsonderrig. Statisries beduidende verskille is gevind in die persepsies van oorwegend intrinsieke en oorwegend ekstrinsieke studente. Die implikasies van die bevindinge word bespreek, asook implikasies vir afstandsonderrigmstellings en organisasies

Intrinsic and extrinsic risk factors for nonunion after nonoperative treatment of midshaft clavicle fractures.

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Liu, W; Xiao, J; Ji, F; Xie, Y; Hao, Y

2015-04-01

The optimal treatment of midshaft clavicle fractures remains controversial. Nonunion is usually considered to be an uncommon complication following a nonoperatively treated clavicle fracture. Not every midshaft clavicular fractures shares the same risk of developing nonunion after nonoperative treatment. The present study was performed to identify the intrinsic and extrinsic independent factors that are independently predictive of nonunion in patients with midshaft clavicular fractures after nonoperative treatment. We performed a retrospective study of a series of 804 patients (391 men and 413 women with a median age of 51.3 years) with a radiographically confirmed midshaft clavicle fracture, which was treated nonoperatively. There were 96 patients who underwent nonunion. Putative intrinsic (patient-related) and extrinsic (injured-related) risk factors associated with nonunion were determined with the use of bivariate and multivariate statistical analyses. By bivariate analysis, the risk of nonunion was significantly increased by several intrinsic risk factors including age, sex, and smoking and extrinsic risk factors including displacement of the fracture and the presence of comminution (P<0.05 for all). On multivariate analysis, smoking (OR=4.16, 95% CI: 1.01-14.16), fracture displacement (OR=7.81, 95% CI: 2.27-25.38) and comminution of fracture (OR=3.86, 95% CI: 1.16-13.46) were identified as independent predictive factors. The risk factors for nonunion after nonoperative treatment of midshaft clavicle fractures are multifactorial. Smoking, fracture displacement and comminution of fracture are independent predictors for an individual likelihood of nonunion. Further studies are still required to evaluate these factors in the future. Level III, case-control study. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Comparison of extrinsic and intrinsic neuromodulation in two central pattern generator circuits in invertebrates.

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Katz, P S

1998-05-01

There are many sources of modulatory input to CPGs and other types of neuronal circuits. These inputs can change the properties of cells and synapses and dramatically alter the production of motor patterns. Sometimes this enables the production of motor patterns by the circuit. At other times, the modulation allows alternate motor patterns to be produced by a single circuit. Modulatory neurones have fast as well as slow actions. In some cases, such as with GPR, the two types of effects are due to the release of co-transmitters. In other cases, such as with the DSIs, a single substance can act at different receptors to cause fast and slow postsynaptic actions. The effect of a neuromodulatory neurone is determined by the type of receptor on the target neurone. Thus a single modulatory neurone evokes a suite of actions in a circuit and thereby produces a co-ordinated output. Extrinsic and intrinsic sources of neuromodulation have different sets of constraints acting upon them. For example, extrinsic neuromodulation can easily be used for motor pattern selection; a different pattern is produced depending upon which modulatory inputs are active. However, intrinsic neuromodulation is not well suited to that task. Instead, it is useful for self-organizing properties and experience-dependent effects. One clear conclusion from this work and other work in the field is that neuromodulation by neurones intrinsic and extrinsic to CPGs is not uncommon (Katz, 1995; Katz & Frost, 1996). It is part of the normal process of motor pattern generation. As such, it needs to be considered when discussing mechanisms for neuronal circuit actions.

Evidence for a Significant Level of Extrinsic Anisotropy Due to Heterogeneities in the Mantle.

Science.gov (United States)

Alder, C.; Bodin, T.; Ricard, Y. R.; Capdeville, Y.; Debayle, E.; Montagner, J. P.

2017-12-01

Observations of seismic anisotropy are used as a proxy for lattice-preferred orientation (LPO) of anisotropic minerals in the Earth's mantle. In this way, it provides important constraints on the geometry of mantle deformation. However, in addition to LPO, small-scale heterogeneities that cannot be resolved by long-period seismic waves may also produce anisotropy. The observed (i.e. apparent) anisotropy is then a combination of an intrinsic and an extrinsic component. Assuming the Earth's mantle exhibits petrological inhomogeneities at all scales, tomographic models built from long-period seismic waves may thus display extrinsic anisotropy. Here, we investigate the relation between the amplitude of seismic heterogeneities and the level of induced S-wave radial anisotropy as seen by long-period seismic waves. We generate some simple 1D and 2D isotropic models that exhibit a power spectrum of heterogeneities as what is expected for the Earth's mantle, i.e. varying as 1/k, with k the wavenumber of these heterogeneities. The 1D toy models correspond to simple layered media. In the 2D case, our models depict marble-cake patterns in which an anomaly in S-wave velocity has been advected within convective cells. The long-wavelength equivalents of these models are computed using upscaling relations that link properties of a rapidly varying elastic medium to properties of the effective, i.e. apparent, medium as seen by long-period waves. The resulting homogenized media exhibit extrinsic anisotropy and represent what would be observed in tomography. In the 1D case, we analytically show that the level of anisotropy increases with the square of the amplitude of heterogeneities. This relation is numerically verified for both 1D and 2D media. In addition, we predict that 10 % of chemical heterogeneities in 2D marble-cake models can induce more than 3.9 % of extrinsic radial S-wave anisotropy. We thus predict that a non-negligible part of the observed anisotropy in tomographic

Intrinsic and Extrinsic Motivation and Attitudes toward Professional Continuing Education: Implications for the Counselors.

Science.gov (United States)

Drummond, Robert J.; Croll, James C.

1983-01-01

Surveyed 3,266 bankers enrolled in a continuing education program to examine differences in motivation. Results showed the largest group listed future advancement as an intrinsic motivational factor. Those in the extrinsic group listed personal growth as a motivator. Counseling strategies to increase employee self-confidence were also discussed.…

Associations of Extrinsic and Intrinsic Components of Work Stress with Health: A Systematic Review of Evidence on the Effort-Reward Imbalance Model.

Science.gov (United States)

Siegrist, Johannes; Li, Jian

2016-04-19

Mainstream psychological stress theory claims that it is important to include information on people's ways of coping with work stress when assessing the impact of stressful psychosocial work environments on health. Yet, some widely used respective theoretical models focus exclusively on extrinsic factors. The model of effort-reward imbalance (ERI) differs from them as it explicitly combines information on extrinsic and intrinsic factors in studying workers' health. As a growing number of studies used the ERI model in recent past, we conducted a systematic review of available evidence, with a special focus on the distinct contribution of its intrinsic component, the coping pattern "over-commitment", towards explaining health. Moreover, we explore whether the interaction of intrinsic and extrinsic components exceeds the size of effects on health attributable to single components. Results based on 51 reports document an independent explanatory role of "over-commitment" in explaining workers' health in a majority of studies. However, support in favour of the interaction hypothesis is limited and requires further exploration. In conclusion, the findings of this review support the usefulness of a work stress model that combines extrinsic and intrinsic components in terms of scientific explanation and of designing more comprehensive worksite stress prevention programs.

Associations of Extrinsic and Intrinsic Components of Work Stress with Health: A Systematic Review of Evidence on the Effort-Reward Imbalance Model

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Johannes Siegrist

2016-04-01

Full Text Available Mainstream psychological stress theory claims that it is important to include information on people’s ways of coping with work stress when assessing the impact of stressful psychosocial work environments on health. Yet, some widely used respective theoretical models focus exclusively on extrinsic factors. The model of effort-reward imbalance (ERI differs from them as it explicitly combines information on extrinsic and intrinsic factors in studying workers’ health. As a growing number of studies used the ERI model in recent past, we conducted a systematic review of available evidence, with a special focus on the distinct contribution of its intrinsic component, the coping pattern “over-commitment”, towards explaining health. Moreover, we explore whether the interaction of intrinsic and extrinsic components exceeds the size of effects on health attributable to single components. Results based on 51 reports document an independent explanatory role of “over-commitment” in explaining workers’ health in a majority of studies. However, support in favour of the interaction hypothesis is limited and requires further exploration. In conclusion, the findings of this review support the usefulness of a work stress model that combines extrinsic and intrinsic components in terms of scientific explanation and of designing more comprehensive worksite stress prevention programs.

Associations of Extrinsic and Intrinsic Components of Work Stress with Health: A Systematic Review of Evidence on the Effort-Reward Imbalance Model

Science.gov (United States)

Siegrist, Johannes; Li, Jian

2016-01-01

Mainstream psychological stress theory claims that it is important to include information on people’s ways of coping with work stress when assessing the impact of stressful psychosocial work environments on health. Yet, some widely used respective theoretical models focus exclusively on extrinsic factors. The model of effort-reward imbalance (ERI) differs from them as it explicitly combines information on extrinsic and intrinsic factors in studying workers’ health. As a growing number of studies used the ERI model in recent past, we conducted a systematic review of available evidence, with a special focus on the distinct contribution of its intrinsic component, the coping pattern “over-commitment”, towards explaining health. Moreover, we explore whether the interaction of intrinsic and extrinsic components exceeds the size of effects on health attributable to single components. Results based on 51 reports document an independent explanatory role of “over-commitment” in explaining workers’ health in a majority of studies. However, support in favour of the interaction hypothesis is limited and requires further exploration. In conclusion, the findings of this review support the usefulness of a work stress model that combines extrinsic and intrinsic components in terms of scientific explanation and of designing more comprehensive worksite stress prevention programs. PMID:27104548

Effect of extrinsic incentives on use of test anxiety as an anticipatory attributional defense: playing it cool when the stakes are high.

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Greenberg, J; Pyszczynski, T; Paisley, C

1984-11-01

We conducted an experiment to assess the effect of extrinsic incentives on the use of test anxiety as a self-handicapping strategy. We hypothesized that although reports of anxiety may be greater when such symptoms can serve a defensive function, this effect occurs only when extrinsic incentives are low and not under conditions of high extrinsic incentive. Eighty-four male undergraduates anticipated taking a test of intellectual abilities and either were led to believe that test anxiety has no effect on test performance or were given no particular information about the relation between test anxiety and performance. Subjects were offered either +5 or +25 for obtaining the highest score on the test. Consistent with predictions, no-information subjects reported greater test anxiety before the test than did those who believed that test anxiety was unrelated to performance, but only when the extrinsic incentive for performance was low. However, these subjects did not report greater cognitive interference or exhibit lower test scores than did subjects in other conditions. It is tentatively suggested that the defensive strategy used by these subjects consisted of altering perceptions of anxiety, rather than anxiety itself. The implications of the absence of self-handicapping under high incentive conditions are discussed.

Characterizing Facial Skin Ageing in Humans: Disentangling Extrinsic from Intrinsic Biological Phenomena

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Trojahn, Carina; Dobos, Gabor; Lichterfeld, Andrea; Blume-Peytavi, Ulrike; Kottner, Jan

2015-01-01

Facial skin ageing is caused by intrinsic and extrinsic mechanisms. Intrinsic ageing is highly related to chronological age. Age related skin changes can be measured using clinical and biophysical methods. The aim of this study was to evaluate whether and how clinical characteristics and biophysical parameters are associated with each other with and without adjustment for chronological age. Twenty-four female subjects of three age groups were enrolled. Clinical assessments (global facial skin ageing, wrinkling, and sagging), and biophysical measurements (roughness, colour, skin elasticity, and barrier function) were conducted at both upper cheeks. Pearson's correlations and linear regression models adjusted for age were calculated. Most of the measured parameters were correlated with chronological age (e.g., association with wrinkle score, r = 0.901) and with each other (e.g., residual skin deformation and wrinkle score, r = 0.606). After statistical adjustment for age, only few associations remained (e.g., mean roughness (R z) and luminance (L *),  β = −0.507, R 2 = 0.377). Chronological age as surrogate marker for intrinsic ageing has the most important influence on most facial skin ageing signs. Changes in skin elasticity, wrinkling, sagging, and yellowness seem to be caused by additional extrinsic ageing. PMID:25767806

Characterizing Facial Skin Ageing in Humans: Disentangling Extrinsic from Intrinsic Biological Phenomena

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Carina Trojahn

2015-01-01

Full Text Available Facial skin ageing is caused by intrinsic and extrinsic mechanisms. Intrinsic ageing is highly related to chronological age. Age related skin changes can be measured using clinical and biophysical methods. The aim of this study was to evaluate whether and how clinical characteristics and biophysical parameters are associated with each other with and without adjustment for chronological age. Twenty-four female subjects of three age groups were enrolled. Clinical assessments (global facial skin ageing, wrinkling, and sagging, and biophysical measurements (roughness, colour, skin elasticity, and barrier function were conducted at both upper cheeks. Pearson’s correlations and linear regression models adjusted for age were calculated. Most of the measured parameters were correlated with chronological age (e.g., association with wrinkle score, r=0.901 and with each other (e.g., residual skin deformation and wrinkle score, r=0.606. After statistical adjustment for age, only few associations remained (e.g., mean roughness (Rz and luminance (L*,  β=-0.507, R2=0.377. Chronological age as surrogate marker for intrinsic ageing has the most important influence on most facial skin ageing signs. Changes in skin elasticity, wrinkling, sagging, and yellowness seem to be caused by additional extrinsic ageing.

The effect of extrinsic attributes on liking of cottage cheese.

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Hubbard, E M; Jervis, S M; Drake, M A

2016-01-01

Preference mapping studies with cottage cheese have demonstrated that cottage cheese liking is influenced by flavor, texture, curd size, and dressing content. However, extrinsic factors such as package, label claims, and brand name may also influence liking and have not been studied. The objective of this study was to evaluate the role of package attributes and brand on the liking of cottage cheese. A conjoint survey with Kano analysis (n=460) was conducted to explore the effect of extrinsic attributes (brand, label claim, milkfat content, and price) on liking. Following the survey, 150 consumers evaluated intrinsic attributes of 7 cottage cheeses with and without brand information in a 2-d crossover design. Results were evaluated by 2-way ANOVA and multivariate analyses. Milkfat content and price had the highest influence on liking by conjoint analysis. Cottage cheese with 2% milkfat and a low price was preferred. Specific label claims such as "excellent source of calcium (>10%)" were more attractive to consumers than "low sodium" or "extra creamy." Branding influenced overall liking and purchase intent for cottage cheeses to differing degrees. For national brands, acceptance scores were enhanced in the presence of the brand. An all-natural claim was more appealing than organic by conjoint analysis and this result was also confirmed with consumer acceptance testing. Findings from this study can help manufacturers, as well as food marketers, better target their products and brands with attributes that drive consumer choice. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Intrinsic and extrinsic magnetic properties of the naturally layered manganites

International Nuclear Information System (INIS)

Berger, A.; Mitchell, J. F.; Miller, D. J.; Jiang, J. S.; Bader, S. D.

1999-01-01

Structural and magnetic properties of the two-layered Ruddlesden-Popper phase SrO(La 1-x Sr x MnO 3 ) 2 with x = 0.3--0.5 are highlighted. Intrinsic properties of these naturally layered manganites include a colossal magnetoresistance, a composition-dependent magnetic anisotropy, and almost no remanence. Above the Curie temperature there is a non-vanishing extrinsic magnetization attributed to intergrowths (stacking faults in the layered structure). These lattice imperfections consist of additional or missing manganite layers, as observed in transmission electron microscopy. Their role in influencing the properties of the host material is highlighted

Theoretical study of high-Q Fano resonance and extrinsic chirality in an ultrathin Babinet-inverted metasurface

Science.gov (United States)

Wang, Feng; Wang, Zhengping; Shi, Jinhui

2014-10-01

A high-Q Fano resonance and giant extrinsic chirality have been demonstrated in an ultrathin Babinet-inverted metasurface composed of asymmetrical split ring apertures (ASRAs) perforated through a metal plate based on the full-wave simulations. The performance of the Fano resonance at normal incidence strongly depends on the asymmetry of the ASRA. The quality factor is larger than 1000 and the local field enhancement is an order of 104. For oblique incidence, giant extrinsic chirality can be achieved in the Babinet-inverted metasurface. It reveals a cross-polarization transmission band with a ripple-free peak and also a spectrum split for large angles of incidence. The electromagnetic response of the metasurface can be easily tuned via angles of incidence and asymmetry. The proposed ASRA metasurface is of importance to develop many metamaterial-based devices, such as filters and circular polarizers.

Properties and toughening mechanisms of PVA/PAM double-network hydrogels prepared by freeze-thawing and anneal-swelling.

Science.gov (United States)

Ou, Kangkang; Dong, Xia; Qin, Chengling; Ji, Xinan; He, Jinxin

2017-08-01

It is well known that preparation method of hydrogels has a significant effect on their properties. In this paper, freeze-thawing and anneal-swelling were applied to prepare poly(vinyl alcohol)/polyacrylamide (PVA/PAM) double-network hydrogels with covalently and physically cross-linked networks. The properties of these hydrogels were investigated and compared to control hydrogels. Results indicated that hydrogels fabricated by freeze-thawing show larger pores size and higher swelling capacity than those made by anneal-swelling and control hydrogels. Hydrogels prepared by anneal-swelling exhibit higher mechanical strength, energy dissipation, fracture energy, gel fraction and crystallinity than those made by freeze-thawing and control hydrogels. Physical cross-linking plays a key role in formation of physical-chemical double-network. The toughening mechanism of double-network hydrogel is related to their chain-fracture behavior and elasticity. The results also indicated that appropriate methods can endow hydrogels with specific microstructures and properties which would broaden current hydrogels research and applications in biomedical fields. Copyright © 2017 Elsevier B.V. All rights reserved.

Intrinsic and extrinsic permeability of ferromagnetic thin films and multilayers for frequency dependence: comparison between theory and experiment

International Nuclear Information System (INIS)

Berthault, A.; Durbin, F.; Russat, J.

1992-01-01

Soft ferromagnetic thin films are attractive materials for read/write head applications because they exhibit a high magnetic permeability in the hundred MHz range. By contrast, due to their low electrical resistivity, their processability at higher frequency is somewhat limited. Using Maxwell equations and the geometry of the processed material, we have developed a theoretical model of the frequency-dependent magnetic permeability useful for multilayers design. We have distinguished different cases: - extrinsic (measured) vs intrinsic permeability in magnetic thin films and magnetic-insulator multilayers, - intrinsic vs extrinsic permeability in magnetic thin films, computes by the Newton iterative method. Using the well-know Landau-Lifshitz model for high frequency permeability, we have compared experimental and theoretical results. (orig.)

Impact of extrinsic factors on fine motor performance of children attending day care

Directory of Open Access Journals (Sweden)

Carolina Corsi

Full Text Available Abstract Objective: To assess the impact of extrinsic factors on fine motor performance of children aged 2-years old. Methods: 73 children attending public and 21 private day care centers were assessed. Day care environment was evaluated using the Infant/Toddler Environment Rating Scale-Revised Edition (ITERS-R, fine motor performance was assessed through the Bayley Scales of Infant and Toddler Development-III (BSITD-III, socioeconomic data, maternal education and time of start at the day care were collected through interviews. Spearman's correlation coefficient was calculated to assess the association between the studied variables. Results: The time at the day care was positively correlated with the children's performance in some fine motor tasks of the BSITD-III, showing that the activities developed in day care centers were important for the refinement of specific motor skills, while the overall fine motor performance by the scale was associated with maternal education and the ITERS-R scale sub-item “language and understanding”. Conclusions: Extrinsic factors such as higher maternal education and quality of day care centers are associated with fine motor performance in children attending day care.

Impact of extrinsic factors on fine motor performance of children attending day care.

Science.gov (United States)

Corsi, Carolina; Santos, Mariana Martins Dos; Marques, Luísa de Andrade Perez; Rocha, Nelci Adriana Cicuto Ferreira

2016-12-01

To assess the impact of extrinsic factors on fine motor performance of children aged two years old. 73 children attending public and 21 private day care centers were assessed. Day care environment was evaluated using the Infant/Toddler Environment Rating Scale - Revised Edition (ITERS-R), fine motor performance was assessed through the Bayley Scales of Infant and Toddler Development - III (BSITD-III), socioeconomic data, maternal education and time of start at the day care were collected through interviews. Spearman's correlation coefficient was calculated to assess the association between the studied variables. The time at the day care was positively correlated with the children's performance in some fine motor tasks of the BSITD-III, showing that the activities developed in day care centers were important for the refinement of specific motor skills, while the overall fine motor performance by the scale was associated with maternal education and the ITERS-R scale sub-item "language and understanding". Extrinsic factors such as higher maternal education and quality of day care centers are associated with fine motor performance in children attending day care. Copyright © 2016 Sociedade de Pediatria de São Paulo. Publicado por Elsevier Editora Ltda. All rights reserved.

A Quantitative Analysis of the Extrinsic and Intrinsic Turnover Factors of Relational Database Support Professionals

Science.gov (United States)

Takusi, Gabriel Samuto

2010-01-01

This quantitative analysis explored the intrinsic and extrinsic turnover factors of relational database support specialists. Two hundred and nine relational database support specialists were surveyed for this research. The research was conducted based on Hackman and Oldham's (1980) Job Diagnostic Survey. Regression analysis and a univariate ANOVA…

The Relationship between Future Goals and Achievement Goal Orientations: An Intrinsic-Extrinsic Motivation Perspective

Science.gov (United States)

Lee, Jie Qi; McInerney, Dennis M.; Liem, Gregory Arief D.; Ortiga, Yasmin P.

2010-01-01

This research aimed to study the relationships between students' future goals (FGs) and their immediate achievement goal orientations (AGOs) among 5733 Singaporean secondary school students (M age = 14.18, SD = 1.26; 53% boys). To this end, we hypothesized that the relationships between like valenced FGs and AGOs (both intrinsic or both extrinsic)…

Intrinsic and Extrinsic Factors That Influence Black Males to Attend Institutions of Higher Education

Science.gov (United States)

Etheridge, Robert

2013-01-01

The purpose of this qualitative, narrative study was to explore the intrinsic and extrinsic factors that motivated Black males to attend institutions of higher education. The Self-determination theory and the Integrated Model for Educational Choice formed the theoretical framework for this study. Eight Black males who were between the ages of 18…

Study of toughening mechanisms through the observations of crack propagation in nanostructured and layered metallic sheet

International Nuclear Information System (INIS)

Chen, A.Y.; Li, D.F.; Zhang, J.B.; Liu, F.; Liu, X.R.; Lu, J.

2011-01-01

Highlights: → A nanostructured and layered steel exhibits high strength and large ductility. → The excellent combination originates from a multiple interlaminar cracking. → The initiation and propagation of cracks are controlled by three aspects. → The cracks are deflected by interface and arrested by compressive residual stress. → Finally, the cracks are blunted by the graded grain size distribution. - Abstract: A layered and nanostructured (LN) 304 SS sheet was produced by combination of surface mechanical attrition treatment (SMAT) with warm co-rolling. The microstructure of LN sheet is characterized by a periodic distribution of nanocrystalline layers and micron-grained layers with a graded transition of grain size. Tensile test results show that exceptional properties of high yield strength and large elongation to fracture are achieved. A multiple interlaminar cracking was observed by scanning electron microscopy, which is induced by repeated crack initiation and propagation. The toughening mechanisms of the LN sheet are proposed to be controlling the crack propagation path by several strategies. The main cracks initiating at interface defects are arrested by large compressive residual stress, deflected by weak interface bonding and blunted by the graded grain size distribution.

Increasing Elementary and High School Student Motivation through the Use of Extrinsic and Intrinsic Rewards

Science.gov (United States)

Haywood, Joey; Kuespert, Sarah; Madecky, Dani; Nor, Abbey

2008-01-01

This action research project report examined strategies to motivate students from extrinsically rewarding behaviors to intrinsically motivating behaviors. The action research was conducted in two different schools by four different teacher researchers within the same district. Three teachers in an elementary building (Site A) and one teacher in a…